• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.10
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• pp.176-180
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• 2007

In the case that an overcurrent flows through in electrical wire due to short-circuit or overload, the wire can be fused, thereby causing an electrical fire. In the present article the characteristics of the fusing current of an electrical wire have been studied to discriminate between short-circuit and overload. In the experiment the fusing time was measured as the currents determined by Preece's equation were supplied to bare wires of various diameter. As the results of experiment, the measured fusing currents well satisfied the Onderdonk's equation. By comparing the measured results and the short current the IEC recommends, it is shown that the variable to determine the short current for a bare copper wire, k is appoximately 300. The fusing current of an electrical wire which becomes a short circuit within 5sec can be expressed as a function of diameter based on the value of k. Consequently, the equation for the fusing current provides a criterion to discriminate between short-circuit and overload.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.8
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• pp.1163-1171
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• 2017

The problem of fault current to exceed the rated capacity of a power circuit breaker can cause a serious accident to hurt the reliability of the power system. In order to solve this issue, current limiting reactors and circuit breakers with increased capacity are utilized but these solutions have some technical limitations. Back-to-back high voltage direct current(BTB HVDC) may be applied for reducing the fault current. When BTB HVDCs are installed for reduction in fault current, selecting the optimal location of the BTB HVDC without causing overload of line power becomes a key point. In this paper, we use genetic algorithm to find optimal location effectively in a short time. We propose a new methodology for determining the BTB HVDC optimal location to reduce fault current without causing overload of line power in metropolitan areas. Also, the procedure of performing the calculation of fault current and line power flow by PSS/E is carried out automatically using Python. It is shown that this optimization methodology can be applied effectively for determining the BTB HVDC optimal location to reduce fault current without causing overload of line power by a case study.

• The Journal of the Korea Contents Association
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• v.16 no.6
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• pp.516-528
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• 2016

Tourism information related to the selection and the images formation of tourist destinations is getting more important in tourism industry, and the problems of information overflow is also on the rise simultaneously. And this information overflow can affect the tourists' cognition, emotion and attitudes about tourism information. The objective of this study is to assess their information overload on tourism information on tourists' emotion, attitude and information searching effort. Data were collected from total 438 people with 224 people at public spaces in Seoul, Korea and 214 people at public spaces in Xi'an, China. This study conducts confirmatory factor analysis, correlation analysis and structural equation modelling to verifying 5 hypothesis related to information overflow. The main results of the study show that the cognition of information overload can lead to positive effect to tourists' positive emotion, attitude and searching effort.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.6
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• pp.76-95
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• 2019

An on-board truck scale is an essential technical solution for preventing overload, which makes the driver aware of the commercial vehicle weight. This study analyzed the effects of the driving pattern and transportation efficiency by the IoT Platform service for an on-board truck scale. A comparison of before and after installation using the long-term monitored data confirmed the reduction effects both of the overload ratio and overweight value, and their effects on increasing the transportation efficiency. In addition, the analysis result of the driving route showed that the installation of an on-board truck scale could be a more effective way of preventing overload than increasing the weighing checkpoints.

• Childhood Kidney Diseases
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• v.15 no.2
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• pp.107-115
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• 2011

Acute kidney injury (AKI) is associated with mortality and may lead to increased medical expense. A modified criteria (pediatric RIFLE [pRIFLE]: Risk, Injury, Failure, Loss, and End-stage renal disease) has been proposed to standardize the definition of AKI. The common causes of AKI are renal ischemia, nephrotoxic medications, and sepsis. A majority of critically ill children develop AKI by the pRIFLE criteria and need to receive intensive care early in the course of AKI. Factors influencing patient survival (pediatric intensive care unit discharge) are known to be low blood pressure at the onset of renal replacement therapy (RRT), the use of vasoactive pressors during RRT, and the degrees of fluid overload at the initiation of RRT. Early intervention of continuous RRT (CRRT) has been introduced to reduce mortality and fluid overload that affects poor prognosis in patients with AKI. Here, we briefly review the practical prescription of pediatric CRRT and literatures on the outcomes of patients with AKI receiving CRRT and associations among AKI, fluid overload, and CRRT. In conclusion, we suggest that an increased emphasis should be placed on the early initiation of CRRT and fluid overload in the management of pediatric AKI.

• Korean Journal of Occupational Health Nursing
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• v.22 no.2
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• pp.130-139
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• 2013

Purpose: This study was to identify the relationship among clinical nurse's job overload, self-efficacy, emotional exhaust and turnover intention. Methods: The study was conducted through a survey on 537 clinical nurses in five general hospitals. The data were collected by self-reporting questionnaires and analysed by the SPSS/WIN 17.0 program using descriptive statistics, t-test, ANOVA, Pearson correlation coefficient and stepwise multiple regression. Results: The mean score of turnover intention was 3.04. Turnover intention according to age, total career, job objective, and work off showed significant differences. The significant positive correlations between emotional exhaust and turnover intention (r=.531, p<.001), job overload and turnover intention (r=.514, p<.001) were found. The significant factors influencing turnover intention were emotional exhaust (${\beta}$=.488, p<.001), career (${\beta}$=.175, p<.001), job overload (${\beta}$=.119, p= .003), and number of night (${\beta}$=.117, p=.002), which accounted for 40.3% of the variance. Conclusion: Thought this result, nursing managers should analyze the reasons for high turnover intention, focusing on the main factors affecting turnover intention and consider the solutions to decrease the turnover intention.

• Fire Science and Engineering
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• v.21 no.4
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• pp.59-64
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• 2007

We studied on the fires about the electrical motors in this paper. We compared and analyzed about the transformation and damage state of single-phase induction motors used in the home appliances when we applied electrical overload and exterior flame. This experiment was progressed by the electrical overload application test and the exterior flame application test through the locked rotor of motor. In case of the exterior flame application test, it is divided into the apply voltage case and not apply voltage case. The result of an experiment through the locked rotor of motor, it was able to observe the short-circuit marks between layers at the winding coil parts, and it was appeared a transformed dendritic tissue structure of winding coil by the electrical overload test. The application voltage and the application exterior flame, it was confirmed that the stator winding coil parts were remain original shapes and observed that the color of the winding coil's circumference was changed to red. The non-application voltage and the application exterior flame, it was observed that the stator winding coil parts were transformed quite from original shapes. It was observed that the color of the winding coil and circumference parts was changed to red at the same case of non-application voltage.

• Journal of the Korea Convergence Society
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• v.8 no.3
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• pp.1-13
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• 2017

The aim of this study is to investigate the demographical differences in technostressors(cause technological stresses). Although previous studies have been conducted to investigate the factors that affect technostress, little studies have examined the differences in demographic factors. Therefore, this study empirically attempts to investigate how level of technostressors differ by demographic factors. Independent sample t-test was used to identify differences after dividing sample into two groups. The technostressors used in this work are work overload, life invasion, complexity of technology, job insecurity, pace of technological change. We found that, sex and position show a significant difference in pace of technological change. In the educational level, there is a difference between work overload. Work overload, life invasion, complexity of technology, and pace of change show differences in age group. In computer knowledge, there are differences in complexity technology, job insecurity, and pace of change. On the other hand, there is no difference in computer using hours. Conclusions and implications are discussed in final section.

• Journal of the Korea Society for Simulation
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• v.27 no.3
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• pp.45-52
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• 2018

We consider the busy period of an M/G/1/K queueing system with queue-length-dependent overload control policy. A variant of an oscillating control strategy that was recently analyzed by Choi and Kim (2016) is considered: two threshold values, $L_1({\leq_-}L_2)$ and $L_2({\leq_-}K)$, are assumed, and service rate and arrival rate are adjusted depending on the queue length to alleviate congestion. We investigate the busy period of an M/G/1/K queue with two overload control policies, and present the formulae to obtain the expected length of a busy period for each control policy. Based on the numerical examples, we conclude that the variability and expected value of the service time distribution have the most influence on the length of a busy period.

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.5
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• pp.423-430
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• 2009

Recently as the inactive response characteristics of the existing RCD used on low voltage power distribution system, so control of overload and electric short circuit faults, major causes of electrical fires, are not enough. Therefore, this paper confirms the unreliability of the existing RCD by electrical fault simulator and proposes a EFDPD by using semiconductor switching devices and a high precision current sensor (namely, reed switch) for the prevention of electrical disasters in low voltage power distribution system caused by overload or electric short circuit faults. The sensitive reed switch in the proposed EFDPD exactly detects the increased magnetic flux with the overload or the short current caused by a number of electrical faults, and the following, the self circuit breaker in EFDPD rapidly cuts off the system. The proposed EFDPD confirms the excellent characteristics in response velocity and accuracy in comparison with the conventional circuit breaker through various operation performance analysis. The proposed EFDPD can also prevent electrical disasters, like as electrical fires, which resulted from the malfunction and inactive response characteristics of the existing RCD.