• Journal of the speleological society of Korea
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• no.8
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• pp.65-76
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• 1998

This article is based upon a talk given at the 1983 National Caving Conference explaining the types of personal computers available, their main features and how they could be used in connection with caving. There may be two groups of readers particularly interested in this subject, those covers with use of a computer who want some ideas on using it and others who want to know if getting a computer to use in connection with caving might be worth their while.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.1
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• pp.61-69
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• 2007

In a large complex system, maintenance priorities for the failed components are important to maintain the sys-tern reliability at required level. Commonly used methods of determining maintenance priorities are based onranking the failed components by using reliability importance measures such as Birnbaum reliability importance,risk achievement worth and F-V importance, etc. In the preceding works, maintenance priorities for the failedcomponents are determined by using such existing measures, In this study, a new method of determining main-tenance priorities, which utilizes the joint reliability importance is proposed. By investigating the sign of thejoint reliability importance, maintenance priorities obtained by the existing methods are adjusted to yield new re-vised priorities. The revised maintenance priorities are shown to be more effective than the existing ones fromthe standpoint of the speed of system recovery, Effectiveness of the proposed method is illustrated by numericalexamples.

• Korean Journal of Human Ecology
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• v.12 no.3
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• pp.275-286
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• 2003

The purposes of this study were to identify the relationship between children's personality traits and self-esteem, and to find out if there were any differences in the relationship patterns in terms of children's sex. The questionnaire were collected from 984 subjects in 5th grade of elementary schools located in cities of Seoul, Suwon, Daejeon, and Daegu. Results showed that personality factors such as stability, sociability, responsibility, and superiority had stronger correlations with self-esteem factors whereas masculinity, activity level, and reflectivity did so to a less degree. Children's personality factors such as superiority, sociability and responsibility were better predictors of their self-esteem factors such as scholastic competence, social acceptance and general self-worth. Girls showed higher level of stability, sociability, responsibility and superiority, however there was no sex difference in the self-esteem such as scholastic competence, social acceptance and general self-worth. Children's behavioral conduct were mainly explained by masculinity, activity level, and responsibility. Responsibility turned out to be the strongest predictor of behavioral conduct among boys, while the activity level did among girls.

• Nuclear Engineering and Technology
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• v.52 no.9
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• pp.1896-1906
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• 2020

The BEAVRS (Benchmark for Evaluation and Validation of Reactor Simulation) benchmark calculations were performed by DeCART stand-alone and DeCART/MATRA multi-physics coupled code system to verify their accuracy. The solutions of DeCART stand-alone calculations for the control rod bank worth, detector signal, isothermal temperature coefficient, and critical boron concentration agreed very well with the measurements. The root-mean-square errors of the boron letdown curves for two-cycles were less than about 20 ppm, while the individual and total control rod bank worth agreed well within 7.3% and 2.4%, respectively. For the BEAVRS benchmark calculations at the beginning of burnup, the difference between DeCART simplified thermal-hydraulic stand-alone and DeCART/MATRA coupled calculations were not significantly large. Therefore, it is concluded that both the DeCART stand-alone code and the DeCART/MATRA multi-physics coupled code system have the capabilities to generate high fidelity transport solutions at core follow calculations.

• Proceedings of the Society of Korea Industrial and System Engineering Conference
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• 2002.05a
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• pp.9-18
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• 2002

A capital investment problem is essentially one of determining whether the anticipated cash Inflows from a proposed project are sufficiently attractive to invest funds in the project. The net present value(NPV) criterion and internal rate of return(IRR) criterion are widely used as means of making investment decisions. A positive NPV means the equivalent worth of the inflows is greater than the equivalent worth of outflows, so, the project makes profit. Business people are familiar with rates of return because they all borrow money to finance ventures, even If the money they borrow is their own. Thus they are apt to use the IRR in preference to the NPV. The IRR can be defined as the discount rate that causes the net present value of a cash flow to equal zero. Why the project are accepted if the project's IRR is greater than the investor's minimum attractive rate of return. Against the NPV, the definition cannot distinctly explain the concept of the IRR as decision criterion. We present a new definition of the IRR as the ratio of profit on the invested capital.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.25 no.5
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• pp.9-14
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• 2002

A capital investment problem is essentially one of determining whether the anticipated cash inflows from a proposed project are sufficiently attractive to invest funds in the project. The net present value(NPV) criterion and internal rate of return(IRR) criterion are widely used as means of making investment decisions. A positive NPV means the equivalent worth of the inflows is greater than the equivalent worth of outflows, so, the project makes profit. Business people are familiar with rates of return because they all borrow money to finance ventures, even if the money they borrow is their own. Thus they are apt to use the IRR in preference to the NPV. The IRR can be defined as the discount rate that causes the net present value of a cash flow to equal zero. Why the project are accepted if the project's IRR is greater than the investor's minimum attractive rate of return\ulcorner Against the NPV, the definition cannot distinctly explain the concept of the IRR as decision criterion. We present a new definition of the IRR as the ratio of profit on the invested capital.

• The Journal of Information Systems
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• v.21 no.3
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• pp.1-22
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• 2012

This study aims to investigate the effects of UCC parody content trait on user attitude and e-word of mouth. The conventional methods had two identified factors: UCC content factors - trust, usefulness, and information, and parody content factors - humor, satire, and mockery. It also analyzes the impacts gap in UCC attitude between a high-involvement user and a low-involvement user in UCC contents. In this study, our findings are broadly summarized as follows: first, both trust and information, of UCC content factors, showed a positive impact on UCC attitude; second, both humor and satire, of parody content factors, showed a positive impact on UCC attitude; third, UCC attitude showed a positive impact on e-word of mouth, and both humor and satire were highly correlated to UCC attitude in UCC involvement user groups. In conclusion, this study is expected to give useful suggestions on selecting variables for further studies on UCC parody contents.

• Child Health Nursing Research
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• v.13 no.1
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• pp.73-80
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• 2007

Purpose: As a result of dramatic advances in the medical and surgical management of congenital heart disease (CHD), many babies born with cardiac anomalies today can expect to reach adulthood. The main purpose of this study was to examine the relationship between parenting stress and personal resources of mothers of children with CHD. Method: Fifty-one mothers of children with CHD were recruited at the pediatric cardiac outpatient clinic from July 14th to September 25th 2006. Abidin's parenting stress index/short form (PSI/SF) and Brandt and Weinert's personal resource questionnaire (PRQ) were used. PSI has 3 sub-concepts; parental role distress, dysfunctional parent-child interaction, and difficult child. PRQ has 4 sub-concepts; intimacy, social integration, worth, and assistance. Data were analyzed using SPSS 13.0 version. Results: Correlation analysis showed that parenting stress was significantly related to 'intimacy', 'social integration', and 'worth' of mothers. Multiple regression analysis showed that parenting stress was significantly related to personal resource of mother and information by internet. Conclusion: Mothers who felt they had supportive friends and family, high self esteem, and social integration reported lower parenting stress. Also, internet may be an effective method to provide information and share experience for mothers of children with CHD.

• Journal of Families and Better Life
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• v.20 no.2
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• pp.203-214
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• 2002

This study of the relationships between children's depression and anxiety and their children's self-esteem and emotional intelligence had a sample of 984 5th grade children The higher the levels of children's depression and anxiety were, the lower their self-esteem consisting of scholastic competence, social acceptance, atheletic competence, physical appearance, behavioral conduct, and global self-worth were. The higher the levels of children's depression and anxiety were, the lower their emotional intelligence(EI) consisting of self-regulation and emotion utilization, perception of emotion, other-regulation and self-expression were. For boys, scholastic competence and social competence among children's self-esteem factors were the factors best explained by children's depression and anxiety. In addition, boy's perception of emotion was explained by their depression and anxiety. For girls, on the other hand global self-worth and social competence among self-esteem factors were the two factors best explained by their depression and anxiety. Self-regulation and emotion utilization was the El factor best explained by depression and anxiety among girls.

• Journal of Korean Society on Water Environment
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• v.23 no.3
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• pp.356-366
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• 2007

In this paper a methodology is developed to prioritize replacement of water distribution pipes according to the economical efficiency of replacement and assess the long-term effects of water main replacement policies on water distribution systems. The methodology is implemented with MATLAB to develop a computer algorithm which is used to apply the methodology to a case study water distribution system. A pipe break prediction model is used to estimate future costs of pipe repair and replacement, and the economically optimal replacement time of a pipe is estimated by obtaining the time at which the present worth of the total costs of repair and replacement is minimum. The equation for estimating the present worth of the total cost is modified to reflect the fact that a pipe can be replaced in between of failure events. The results of the analyses show that about 9.5% of the pipes in the case study system is required to be replaced within the planning horizon. Analyses of the yearly pipe replacement requirements for the case study system are provided along with the compositions of the replacement. The effects of water main replacement policies, for which yearly replacement length scenario and yearly replacement budget scenario are used, during a planning horizon are simulated in terms of the predicted number of pipe failures and the saved repair costs.