• Journal of KIISE:Information Networking
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• v.29 no.3
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• pp.286-298
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• 2002

The Remote Procedure Call(RPC) has been traditionally used for Inter Process Communication(IPC) among precesses in distributed computing environment. As distributed applications have been complicated more and more, the Mobile Agent paradigm for IPC is emerged. Because there are some paradigms for IPC, researches to evaluate and compare the performance of each paradigm are issued recently. But the performance models used in the previous research did not reflect real distributed computing environment correctly, because they did not consider the evacuation elements for providing security services. Since real distributed environment is open, it is very vulnerable to a variety of attacks. In order to execute applications securely in distributed computing environment, security services which protect applications and information against the attacks must be considered. In this paper, we evaluate and compare the performance of the Remote Procedure Call with that of the Mobile Agent in IPC paradigms. We examine security services to execute applications securely, and propose new performance models considering those services. We design performance models, which describe information retrieval system through N database services, using Petri Net. We compare the performance of two paradigms by assigning numerical values to parameters and measuring the execution time of two paradigms. In this paper, the comparison of two performance models with security services for secure communication shows the results that the execution time of the Remote Procedure Call performance model is sharply increased because of many communications with the high cryptography mechanism between hosts, and that the execution time of the Mobile Agent model is gradually increased because the Mobile Agent paradigm can reduce the quantity of the communications between hosts.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.11 no.2
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• pp.252-261
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• 2000

Objectivity：This study was conducted to examine the depression, self-concept, perception of stress & coping strategy in children with chronic physical illness. Methods：Two groups of participants were recruited for this study, 13 children with chronic illness in outpatient or inpatient treatment at Seoul National University Children's Hospital, and 13 nonpatient children. They were assessed using Korean form of the Piers-Harris Self-Concept Scale (PHSCS), Kovacs' Children's Depression Inventory(CDI) and three subscaleds('color how you feel' 'color how others make you feel' 'A children in the rain' of Children's Self-Report and Projective Inventory(CSRPI). Result：There were significant differences between the chronic ill children and the healthy children in scores of depression and self-concept. The chronicity ill children were more depressive and had very negative self-concept, and obtained significantly lower scores than the healthy children in the subscales of PHSCS, 'intellectual/school status' and 'popularity' Among three scales of CSRPI, there was no difference in 'color how you feel' and 'color how others make you feel' But there were significant differences in all items of 'A child in the rain'(quantity of raining, duration of raining, tool, and effectiveness). 'Duration of raining' correlated most negatively with PHSCS scores, and correlated positively with CDI scores. Conclusion：The children with chronic illness are more depressive and have very negative selfconcept. And they feel that the stresses are more permanent, but have no appropriate coping strategy. The results suggest that the chronic illness strongly affects the psychological and emotional adjustment of children(i.e. depression, peer relation, stress coping strategy).

• 대한공업교육학회지
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• v.44 no.1
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• pp.94-113
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• 2019

This study has been performed for the purpose of providing the basic pedagogical resources to the specialized and meister high school related educational settings in either constructing educational contents suitable for the students'technological thinking disposition or fortifying the disposition required for the students.. A tool of secured validity and reliability has been used to test technological thinking disposition for the specialized and Meister high school students. Followings are the major results of the survey analysis for the subjects. 1. Technological thinking disposition with the most component ratio for the specialized & meister high school was turned out to be Technological Operating Disposition(TOD). The second most was Technological Planning and Reflecting Disposition(TPRD). Technological Curiosity Disposition(TCD), Technological Problem Identifying and Resolving Disposition (TPIRD), Technological Analyzing Disposition(TAD), Technological Creativity and Expressing Disposition(TCED) were in sequence. 2. In comparing the technological disposition of specialized high school students with that of meister high school students, the statistical test showed no evidence for the difference between the two group. 3. Statistical comparison test for the gender difference in technological thinking disposition has also been performed for the students of specialized and meister high school. The result showed that the magnitude of difference between the component ratio of TCD and TPIRD for the boy students was bigger than that for the girl students. In the TPRD, the component ratio for the disposition of the girl students was bigger than that of the boy students on the other hand. 4. For the comparison test of the technological thinking disposition between boys and girls only for the specialized high school students, the results showed the same different component ratio results as the results of the test for the specialized and meister high school students. 5. For the gender difference of meister high school student for the technological thinking disposition, there was no statistical evidence supporting the difference.

• Clinical and Experimental Pediatrics
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• v.48 no.9
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• pp.953-959
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• 2005

Purpose : The administration of total parenteral nutrition(TPN) has become a standard procedure in the management of nutritionally deprived and critically low birth weight neonates. Sepsis remains the most frequent serious complication during TPN, resulting in increased morbidity, mortality and health care costs. This study was performed to evaluate the clinical efficacy and complications of percutaneous central venous catheterization(PCVC) in very low birth weight infants. Methods : A total of 56 very low birth weight infants below 1,500 g during the period from January 1998 to December 2003 were enrolled and their medical records reviewed. Study group(n=32) included the babies who had undergone PCVC and a control group(n=24) included babies who had not undergone PCVC. We compared the study group with the control group for factors such as subject characteristics and catheter-related complications. Results : There was no difference in subject characteristics, such as birth weight, gestational week, respiratory distress syndrome, duration of ventilator therapy, duration from tube to complete oral feeding, days at TPN and its total duration, body weight at discontinuation of TPN and the days taken to reach to 2,000 g. However, the morbidity rate due to patent ductus arterious, chronic lung disease, necrotizing enterocolitis, osteopenia, cholestasis, and sepsis showed no difference. The study group with infants below 1,000 g showed a higher incidence of sepsis compared to the control group of the same weight group. The study group with infants between 1,000 to 1,500 g showed significantly higher incidences of intraventricular hemorrhage and took longer reach the a body weight of 2,000 g. Conclusion : Considering the high incidence of sepsis in the PCVC group, every attempt should be made to minimize the length of TPN therapy and encourage early enteral feeding. We also recommend the use of PCVC carefully in patients requiring prolonged nutritional support.

• Journal of Korea Port Economic Association
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• v.34 no.1
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• pp.111-132
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• 2018

As China continues to evolve as a major economic power and the Free Trade Agreement (FTA) between the Republic of Korea and China was ratified on June 1, 2015, market volume between the two countries is expected to grow more rapidly. This study aims on improving the efficiency of car-ferry lines. We conducted two surveys- for shippers and forwarders of car-ferry companies, and container liners. The study analyzes the decision factors for delivery companies and their importance for shippers and forwarders of car-ferry companies and container liners. Based on analysis of prior studies on the competition for car-ferry companies and liners, three primary variables are selected-promptness, economics, and safety. The promptness variable consists of shipping time, loading/unloading time, and customs clearing time. The economic variable consists of marine transportation cost from a domestic harbor to China, loading/unloading cost in the harbor, and overland transport cost from the harbor to shippers inland. Finally, the safety variable consists of cargo damage rates, safety facilities, such as lashing and shoring, and punctuality of transportation time. The survey and AHP results show that the promptness, safety, and economics factors are 0.549, 0.309, and 0.142 in the shipper groups of car-ferry companies' category, respectively. It indicates that there is considerable difference in the importance of each factor. In contrast, the factors are 0.350, 0.348, and 0.302 in the forwarders category, which suggests that there is little difference in each factor's importance. As for shippers and forwarders of liners, the importance of each factor is found to be in the following order: economics, safety, and promptness.