• Journal of Advanced Marine Engineering and Technology
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• v.39 no.6
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• pp.633-641
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• 2015

Several complex processes that are employed in industries, such as shipping, power plants, and the petrochemical industry, involve time-varying behavior as well as strong nonlinear behavior during operation. The fixed-parameter proportional-integral-derivative (PID) controllers have difficulty in dealing with control problems that occur in such processes. In this paper, we propose a method of designing a nonlinear PID controller for industrial processes that exhibit a large number of nonlinearities and time-varying behavior. The gains of the nonlinear PID controller are characterized by a simple nonlinear function of the error and/or error rate depending on the process set-point and output. We tune the user-defined parameters using a genetic algorithm by minimizing the integral of time absolute error (ITAE) index. We verify the effectiveness of the proposed method by performing a comparison of the proposed method and two other nonlinear and adaptive methods that are employed for reference tracking, disturbance-rejection performances, and robustness to parameter changes on a continuously stirred tank reactor.

• Korean Security Journal
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• no.48
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• pp.235-258
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• 2016

The purpose of this study is to find out the effectiveness of the group guidance program using positive psychology for national security related university entrants' psychological wellbeing. This study is to investigate the influence of group guidance program on the increase of psychological well-being of university entrants through active and deliberate program based on the positive psychology. To achieve this purpose, thirty nine students (male 19, female 20) among national security related university entrants were selected and allocated to experimental and comparative groups. Experimental group was nineteen students (male 10, female 9), and comparative group was twenty students (male 9, female 11). Experimental group was divided into two teams (male and female team), and guided by each leader. The group guidance was participated in total ten-week sessions, fifty mins per week. The results were as follows; First, the group guidance program using positive psychology for national security related university entrants' had a positive effect on the students' psychological wellbeing. Second, effects of subordinate factors (autonomy, controling environment, personal growth, positive relations) in comparison in pre and post test of program had an influence very positive or positive, while one factor (purpose in life) didn't show a positive effect.

• Journal of Distribution Research
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• v.11 no.1
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• pp.99-124
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• 2006

The purposes of the study are two-folds. First, it analyzes how factors other than price(e.g. delivery service, saving point policies, free gifts) impact total price for various products and different types of stores. Second, it analyzes how to increase market efficiencies through price level, price differences, and the frequency of price changes for different shops, various products and different types of transactions. By analyzing the price level within different types of stores, there found that prices at on-line store were lower than off-line shops. It also found price differences between pure on-line, hybrid, and off-line store. Comparing prices by product size, there found that pure on-line shops have a lower price compared to others. The results showed that on-line store had lower price variation compared to off-line shops. When comparing pure on-line store to hybrid store, hybrid store had lower price variation. In terms of the frequency of price changes, hybrid stores had higher price fluctuations. In terms of total price differences for delivery distances, pure on-line store had great price fluctuation, excluding cosmetic goods. In conclusion, if we consider price level and price fluctuations, on-line store had more efficiencies and was superior in terms of price effectiveness. Hybrid shops, on the other hand, had greater advantages for seasonal goods and dominant products. Therefore, market entry strategies should differ based on order quantity, type of store(pure on-line, hybrid, off-line), product characteristics(seasonality, product life), etc.

• The Journal of Korean Physical Therapy
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• v.6 no.1
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• pp.49-60
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• 1994

Stress is experienced when a person tries to maintain stability in the face of life change but is not able to meet the adaptive demands of change. This can be especially true for the parents who has a cerebral palsy childs who needs long term rare, where parents, are the primary source of care and responsibility. Successful coping leads to maintenance of the parents role and this has an effect on the health status of the child. This descriptive study was attempted to identify stress factors, levels and helpful coping patterns for parents who must take care of cerebral palsy children. Data were collected from 43 subjects who were parents of children diagnosed with cerebral palsy The informations gathered from March 25, 1994 to April 14, 1994 by means of structured questionnaires were analyzed. Two instruments were used to collect the data 1) Lee's stress questionnaire consisted of 33 stress factors and measured by four point Likert scale. 2) Modified Chronic Health Inventory for parents: The modified CHIP included 43 items of coping methods with four point Likert scale. The results of this study were as follows: 1) Stress items could have a maximum score of three points, for a total possible score of 132 points. The mean score for the total was 92.02 points. The item mean score was 2.85 points showing that the parents were experiencing moderate to much stress. 2) The items with the highest stress items were 16 items. The stress items with the lowest mean scores were 10 items. 3) Of the stress categories: The highest stress category was related to changes in the illness status of the child and difficulty in taking rare of the child. The second stressful category was related to the prognosis of the child's condition. The least stress was noticed to social-personal relationships and the responsibility of the care givers. 4) Items measuring coping in the parents had a maximum score of three points each with a total possible roping score of 172 points. The mean score for the total was 103,9 paints. The item mean score was 2.42 points indicating that there were responses of little helpful to moderately helpful on each coping pattern. 5) The most helpful coping items were 7 items. The least helpful coping items were 2 items. 6) Effectiveness of the coping for each patterns was examined : Understanding the illness condition from communication with parents of children with the same condition and consultation with the medical team was the most helpful coping pattern. Family's coorperation and integration and optimism were a moderately helpful coping pattern. Social support psychological stability and self esteem were the least helpful toping pattern. In conclusion, the highest stress for parents of children with cerebropalsy was found to be very stressful changes in the illness of the child and to taking care of a child who is suffering. The parents were helped by the coping methods using understanding of the illness condition through consultation with the medical learn and communication with parents in the same situation. Based on the knowledge, care could develop intervention strategies appropriate for them, help them to develop their effective coping patterns, and give support them in the process of coping with their stress.

• Korean Security Journal
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• no.13
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• pp.169-192
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• 2007

School Violence is one of the most serious problems faced by Korean. As this serious problem becomes social issue in nation, many researchers have tried to find out the most effective solution of that problem and the reasons for why prevention of school violence are failed in such mind-hurting activities. The government and NGO proposed many the alternative to prevent the school violence. But the effectiveness of the alternatives art questionable. Last year Busan Metropolitan Police Agency and Busan Education Administration proposed new alternative in united cooperation which is namely Administration proposed new alternative in united cooperation which is namely 'school police' for school violence. School Police is composed of the retired teachers and ex-police officer, to do a prevention activity of school violence, which is expected to effectively curtail school violence in the assigned school. It is first networking try to prevent of school violence as a team of police and teachers in Korea. But the type of Korean school police system is different from American's school police, like as LASPD which is of sworn police officers. Korean school police is to employ a kind of school liaison officers. Though 'School Police System' got good reaction from students and citizen in Busan, It has some defects to be solved in future. So it hard to note that their efforts have been successful in curtailing the prevalence of school violence. In this paper, I present the new type of new 'Social Security Network Model' for school violence by repairing of 'korean school police system'. The problem of the school violence is not the problem of the school but the problem of society. In such viewpoints, It is important to plan a security network model which is participate in police officers, teachers, community and government. To prevent school violence effectively, I propose this new social security network model which based on theory of Community Oriented Policing, aggressive policing and CPTED technique.

• Journal of Chest Surgery
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• v.48 no.5
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• pp.318-327
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• 2015

Background: With improvements in cardiopulmonary resuscitation (CPR) techniques, the quality and the effectiveness of CPR have been established; nevertheless, the survival rate after cardiac arrest still remains poor. Recently, many reports have shown good outcomes in cases where extracorporeal membrane oxygenation (ECMO) was used during prolonged CPR. Accordingly, we attempted to evaluate the impact of extracorporeal cardiopulmonary resuscitation (ECPR) on the survival of patients who experienced a prolonged cardiac arrest and compared it with that of conventional CPR (CCPR). Methods: Between March 2009 and April 2014, CPR, including both in-hospital and out-of-hospital CPR, was carried out in 955 patients. The ECPR group, counted from the start of the ECPR program in March 2010, included 81 patients in total, and the CCPR group consisted of 874 patients. All data were retrospectively collected from the patients' medical records. Results: The return of spontaneous circulation (ROSC) rate was 2.24 times better in CPR of in-hospital cardiac arrest (IHCA) patients than in CPR of out-of-hospital CA (OHCA) patients (p=0.0012). For every 1-minute increase in the CPR duration, the ROSC rate decreased by 1% (p=0.0228). Further, for every 10-year decrease in the age, the rate of survival discharge increased by 31%. The CPR of IHCA patients showed a 2.49 times higher survival discharge rate than the CPR of OHCA patients (p=0.03). For every 1-minute increase in the CPR duration, the rate of survival discharge was decreased by 4%. ECPR showed superiority in terms of the survival discharge in the univariate analysis, although with no statistical significance in the multivariate analysis. Conclusion: The survival discharge rate of the ECPR group was comparable to that of the CCPR group. As the CPR duration increased, the survival discharge and the ROSC rate decreased. Therefore, a continuous effort to reduce the time for the decision of ECMO initiation and ECMO team activation is necessary, particularly during the CPR of relatively young patients and IHCA patients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.121-126
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• 2018

The oral hygiene of patients admitted to the ICU (Intensive Care Unit) is very important. Critically ill patients are basically immunocompromised ones because of the high risk of infection by various pathogenic bacteria. The mouth is not only the primary site of infection, but also the site of systemic infections. The purpose of this study was to design a mouthpiece type vacuum oral cleaner for the oral care of seriously ill patients. A 3D CAD modeling and flow analysis model were established for a double structure type cleaner and standard tooth model, and their pressure and flow characteristics were analyzed. The pressure inside the oral cleaner was almost constant, but the velocity distribution showed a large difference between the inside and outside of the teeth. The velocity at the center region inside of the teeth was the highest, and the speed decreased as the distance from the center increased. In the analysis of the case where the suction tube was replaced by the drainage tube, the velocity at the center of the outer portion of the teeth was the highest. In order to increase the effectiveness of the oral cleaner, alternating between suction and drainage is proposed, and a design complement to increase the speed of the molar region is required.

• Journal of KIISE:Software and Applications
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• v.35 no.3
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• pp.179-188
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• 2008

An important issue in multiagent reinforcement learning is how an agent should team its optimal policy through trial-and-error interactions in a dynamic environment where there exist other agents able to influence its own performance. Most previous works for multiagent reinforcement teaming tend to apply single-agent reinforcement learning techniques without any extensions or are based upon some unrealistic assumptions even though they build and use explicit models of other agents. In this paper, basic concepts that constitute the common foundation of multiagent reinforcement learning techniques are first formulated, and then, based on these concepts, previous works are compared in terms of characteristics and limitations. After that, a policy model of the opponent agent and a new multiagent reinforcement learning method using this model are introduced. Unlike previous works, the proposed multiagent reinforcement learning method utilize a policy model instead of the Q function model of the opponent agent. Moreover, this learning method can improve learning efficiency by using a simpler one than other richer but time-consuming policy models such as Finite State Machines(FSM) and Markov chains. In this paper. the Cat and Mouse game is introduced as an adversarial multiagent environment. And effectiveness of the proposed multiagent reinforcement learning method is analyzed through experiments using this game as testbed.

• Journal of Distribution Science
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• v.10 no.12
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• pp.35-43
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• 2012

Purpose - This study analyzes the effects of types of leadership on the employees of Italian restaurants, its efficacy, and organizational citizenship behavior, utilizing a causal assessment model. In this study, independent variables such as the type of leadership perceived in the manager or chef by an Italian restaurant's employees, and its efficacy were parameters, and the organizational citizenship behavior and organizational effectiveness were the variables representing the results in the hypothesis. The study aimed to draw implications by verifying the leadership via efficacy and the impact on organizational citizenship behavior of Italian restaurants. Research design, data, methodology - For the purpose of this analysis, specific questionnaire items were configured according to the theory and efficacy of the study. From a questionnaire used in organizational citizenship behavior comprising 22 questions, six were modified to suit the research purpose of this study. The configured questionnaire comprised 5 parts and 40 items. A Likert (Likert) 5-point scale was utilized to measure responses to the questionnaire items from the employees of an Italian restaurant in Seoul who participated in the survey. For data collection, 400 questionnaires were distributed, and 344 collected. Factor analysis and reliability verification were conducted using SPSS18.0 and AMOS18.0. A covariance structure analysis was conducted to test the research hypotheses. Results - Based on the results of the analyses, the summary and suggested implications of the research are as follows: The covariance structure analysis used to analyze the kind of effect transformational and transactional leadership styles in Italian restaurant employees had on self-efficacy, group-efficacy, and organizational citizenship behavior, indicated that among the characteristics of transformational leadership (such as, idealized influence, inspirational motivation, individual consideration, and intellectual stimulation), idealized influence and individual consideration had a positive influence on self-efficacy. Idealized influence, individual consideration, conditional reward, and management by exception also positively influenced self-efficacy and altruistic and conscientious behavior (organizational citizenship behavior). Conclusions - Results suggest that with regard to self-efficacy and group efficacy, managers in different departments and chefs should provide team members with a vision for the future, increase their confidence in their abilities, and build their trust in the organization. By evaluating employee performance and experiences, management can demonstrate leadership and encourage organizational citizenship behavior through enjoyable, voluntary participation. Transformational and transactional leadership is effective in group processes that include social-exchange relationships, self-efficacy and group efficacy, and organizational citizenship behavior. However, as this research study utilizes only self-reported data, it has several limitations, such as a vulnerability of errors caused by the various experiment types. A significant limitation of this study is the lack of potential for the duplication of results. The covariance structure analysis, however, provides complementation to limit the impact of errors from self-reporting studies. A future study can extend this research by utilizing different data collection methods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.239-244
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• 2018

A 59-year-old man with no specific medical or family history complained of chest pain and became unconscious. A member of his family, who was a witness, called 119 and gave him dispatcher-assisted cardiopulmonary resuscitation, followed by defibrillation using an automated external defibrillator placed in his apartment. Afterward, he was given two sessions of defibrillation by the 119 emergency squad, then transferred to an emergency medical center with the return of spontaneous circulation. The patient was discharged with cerebral performance category (CPC) 1 15 days later. While dispatcher-assisted cardiopulmonary resuscitation and defibrillation is at its beginning stage in South Korea, this case seems to demonstrate its effectiveness. Moreover, this case suggests it can be particularly useful for helping untrained witnesses use an automated external defibrillator, which may have important implications in regions in which there are delayed responses of the 119 emergency squad to the site. It is also important to develop a plan for improving witness access to and quantitative supply of the South Korean public access defibrillation (PAD) program.