• Proceedings of the KIEE Conference
• /
• 2003.07c
• /
• pp.1858-1860
• /
• 2003

Ground rods as the discharge path are commonly installed to ensure the safety of human beings and facilities from the surge. Accordingly, proper grounding resistance are specified by the grounding types, and the specified resistance are also required to install the lightning protective facilities. it is needed to analyze the difference between these two resistance through the field test. Therefore, in this paper, the impulse response behavior of the ground rods is analyzed by constructing the test facilities and by testing the ground rods in multi-ground power distribution systems. The impulse responses were analyzed, in transient state, by testing the concrete poles as well since the grounding wires are installed in the concrete poles.

• Korean Journal of Construction Engineering and Management
• /
• v.15 no.5
• /
• pp.40-48
• /
• 2014

As CBR(Chemical, Biological, and Radiological) attack increases, the importance of CBR protective facilities is being emphasized. When CBR warfare emerges, a task force team, who exist outside of CBR protective facility, should enter the CBR protective facility through neutralizing process in CCA(Contamination Control Area) and TFA(Toxic Free Area). If a bottleneck occurs in the process or zones, the task force team cannot enter the CBR protective facility efficiently and may cause inefficiency in its operation performance or result in casualties. The current design criteria of the CBR protective facility is only limited to ventilation system and it does not consider how much time it takes to enter the facility. Therefore, this research aims to propose the entering time estimation model with discrete event simulation. To make the simulation model, the procedure performed through CCA and TFA is defined and segmented. The actual time of the procedure are measured and adapted for the simulation model. After running the simulation model, variables effecting the entering time are selected for alternatives with adjustments. This entering time estimation model for CBR protective facility is expected to help take time into consideration during the designing phase of CBR protective facility and help CBR protective facility managers to plan facility operation in a more realistic approach.

• Journal of Korean Public Health Nursing
• /
• v.26 no.2
• /
• pp.341-353
• /
• 2012

Purpose: The purpose of this study was to evaluate Job Satisfaction of Care Helpers. Method: Subjects included 306 Care Helpers. working at geriatric care facilities; these data were collected from May 4 to May 15, 2012. The SPSS WIN 12.0 program was used for statistical analysis of collected data, including actual number, percentage, average, standard deviation, t-test, one way ANOVA, and Cronbach alpha coefficient. Results: 1. The average Job satisfaction was 3.76 and the average of each job satisfaction was the task (3.83), co-worker (2.23), and job turn over (2.25). 2. The satisfaction of the job itself, depending on back ground, had a significantly effect on age, protective person for a day, duty pattern, contract pattern, and motive. 3. The job satisfaction of human relationships, depending on their back ground, had a significant effect on degree, care-giving experience, duty place, protective person for a day, duty pattern, contract pattern, and duty motive. 4. The Job satisfaction of job turn over, depending on back ground had an. effect on job satisfaction statistically: age, degree, duty place, protective person for a day, duty pattern, and motive. Conclusion: These results found showed to contribute to job satisfaction of care helpers.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.60 no.1
• /
• pp.36-42
• /
• 2011

This paper mainly proposes the protective coordination scheme of the microgrid system. The microgrid protection is identical to the conventional protection system separating the normal part and contingency part to reduce damage when the contingency occur at power cables, facilities. But they are different in the protection type. The conventional protection system only considers unidirectional current. However the microgrid protection should be considered not only unidirectional current but also backfeed current because various microsources and loads are installed in the microgrid system. In case the contingency occurs in microsource, when microgrid is interconnected to grid, the protection system should be configured to not separate microgrid from grid before the microsource is isolated to microgrid. And in case of fault occur in power system, the microsources should not isolated to microgrid before the static switch at PCC is tripped to separate from power system. Considering these characteristic of microgird, this paper proposes the protective coordination scheme of microgrid and implemented the on-line real time monitoring system. Especially in case the microgrid is connected to low voltage distribution system with 220/380V voltage level, the proposed protection method with power IT technology can solve the problems when the existing protective devices only applied to the microgrid system.

• Journal of The Korea Institute of Healthcare Architecture
• /
• v.29 no.2
• /
• pp.49-60
• /
• 2023

Purpose: This study aims to establish detailed spatial planning by identifying the needs for a seclusion module for emergency psychiatric patients. Methods: The necessity of medical space with seclusion function was analyzed from spatial, medical, and social perspectives. The needs for a space capable of performing three medical functions: protection, isolation, and treatment, was analyzed. Among various types of mobile medical facilities, seclusion space was considered suitable for utilizing modular construction methods, as it is the most rational method that can satisfy the environmental level of fixed healthcare facilities' space. Therefore, seclusion modules based on modular construction were planned, consisting of two protective units for stabilizing patients with psychiatric illness, one for treatment unit that can accommodate both internal and external treatment, and another one for an infectious disease isolation unit equipped with negative pressure equipment. Implications: This study analyzed the necessary medical functions of the interior space of the mobile stabilization module based on the spatial analysis of existing medical facilities, and proposed alternative spatial configurations according to treatment, seclusion, isolation functions.

• Journal of the Korean Society of Safety
• /
• v.32 no.6
• /
• pp.46-53
• /
• 2017

The risk is expressed as consequence of damage multiplied by likelihood of failure. The installation of a protective system reduces the risk by reducing the likelihood of failure at the facility. Also, the protective system has different effects on the likelihood of failure according to the proof test cycle. However, when assessing risks in the Off-site Risk Assessment (ORA) system, the variation in risk was not reflected according to the proof test cycle of protective system. This study was conducted to examine the need for proof test and the importance of cycle setting by applying periodic proof test of the protective system to ORA. The results showed that the likelihood of failure and the risk increased with longer proof test cycle. The risk of a two-yearly proof test was eight times greater than that of a three-month cycle. From the results, the protective system needs periodic proof test. Untested protective system for a long term cannot be reliable because it is more likely to be failed state when it is called upon to operate. In order to reduce the risk to an acceptable level, it is effective to differently set the proof test cycle according to the priority. This study suggested a more systematic and accurate risk analysis standard than ORA. This standard is expected to enable an acceptable level of risk management by systematically setting the priority and proof test cycle of the protective system. It is also expected to contribute to securing the safety of chemical facilities and at the same time, will lead to the development of the ORA system.

• Tuberculosis and Respiratory Diseases
• /
• v.79 no.4
• /
• pp.234-240
• /
• 2016

Transmission of tuberculosis (TB) is a recognized risk to patients and healthcare workers in healthcare settings. The literature review suggests that implementation of combination control measures reduces the risk of TB transmission. Guidelines suggest a three-level hierarchy of controls including administrative, environmental, and respiratory protection. Among environmental controls, installation of ventilation systems is a priority because ventilation reduces the number of infectious particles in the air. Natural ventilation is cost-effective but depends on climatic conditions. Supplemented intervention such as air-cleaning methods including high efficiency particulate air filtration and ultraviolet germicidal irradiation should be considered in areas where adequate ventilation is difficult to achieve. Personal protective equipment including particulate respirators provides additional benefit when administrative and environmental controls cannot assure protection.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.62 no.9
• /
• pp.1302-1307
• /
• 2013

MOV(Metal Oxide Varistor) is the most important part of SPD(Surge Protective Device) which can protect electric facilities from an impulse current such as a lightning. So far, the fault of MOVs have decided only by surge count without considering magnitude of surge current and an amount of input energy. This paper proposed the fault prediction algorithm for the MOV using look up table made by surge count and input current data which have non-linear characteristics for input current and are estimated by high voltage experimental results. Proposed algorithm was proved by experiment on verification at a high voltage laboratory.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.357-359
• /
• 2004

Fuse is the initial equipment of Protective Relay The installation standard of Fuse has been used for long time in Power Facilities. However according to the innovative development of Electric & Electronic element(=semiconductor) Technology, Protective Relay and other Power Equipments are being changed into Digitalization and Multi-Functional Convergence. In contrast with it, the installation standard of Fuse is just the same. There is a need to give careful consideration to it. This study will bear a Part of producing a safe and efficient Power by examining the current installation of primal 8f secondary 1'use in multi-functional PT of Power plant, giving a problem careful consideration and suggesting suitable countermeasures.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.52 no.2
• /
• pp.134-141
• /
• 2003

The power transformer is one of the very important electric facilities in power systems. Recently, current differential relay is widely used to protect such power transformer But if inrush occurs in transformer, relay can be tripped by judging like internal fault. Therefore the correct discrimination between internal winding fault, inrush and overexcitation should be performed. This paper presents a new protective relaying algorithm which discriminates inrush, internal faults and overexcitation of transformer modelled using BCTRAN and HYSDAT of EMTP. Discrimination between internal winding fault and inrush is revealed in simulation within 1/2 cycle after fault. Accordingly, it is evaluated that the proposed algorithm has better discrimination characteristics in various cases thin the current relaying for protection of transformer.