• Journal of the Korea Safety Management & Science
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• v.11 no.2
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• pp.77-85
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• 2009

Considering heat insulation and beautiful sight of construction, making use of exterior panels is increasing. Recently the exterior panels now are weak very much, and so in consequence of the weakness fire spreads rapidly. Compared with internal fire, external vertical fire spread rate goes rapidly and it is extensive in spread range, therefore it is dangerous very much. Accordingly, under present condition of poor standard of exterior panels, it is required to take measure to meet the appropriate situation. In this study, by making use of FDS(Fire Dynamic Simulation) program about external vertical fire of high rise building, fire behavior is searched by computer. It is important that realizing by computer fire modeling about external vertical fire must be included certainly in procedure of fire performance design in the future. In modeling program, FDS version 5 is available, and aluminium composite panel is applied in external panels. In this study, for realizing of actual fire condition, FDS is applied by details of fire scenarios considering influence of wind.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.546-547
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• 2012

In the three-phase power system using the three-phase load, when any one-phase is open-phase, the unbalanced current flows and the single-phase power supplied by power supply produces over-current. As a result, the enormous damage and electrical fire can be given to the power system. In order to improve these problems, this paper is proposed a new control circuit topology for open-phase protection using semiconductor devices. Therefore, the proposed open-phase protection device (OPPD) enhances the sensing speed and precision, and has the advantage of simple fitting in the three-phase distribution panel in the field, as it manufactures into small size and light weight. As a result, the proposed OPPD minimizes the electrical fire from open-phase, and contributes for the stable driving of the power system.

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.84-96
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• 2022

In the worst case, a temporary ignition source (also known as transient combustibles) between two electrical panels can damage both panels. Mitigation strategies for electrical panel fires were previously developed using fire modeling and risk analysis. However, since they do not comply with deterministic fire protection requirements, it is necessary to analyze the boundary values at which combustibles may damage targets depending on various factors. In the present study, a sensitivity analysis of input variables related to the damage threshold of two electrical panels was performed for dimensionless geometry using a Fire Dynamics Simulator (FDS). A new methodology using a damage evaluation map was developed to assess the damage of the electrical panel. The input variables were the distance between the electrical panels, the vertical height of the fuel, the size of the fire, the wind speed and the wind direction. The heat flux was determined to increase as the vertical distance between the fuel and the panel decreased, and the largest heat flux was predicted when the vertical separation distance divided by one half flame length was 0.3-0.5. As the distance between the panels increases, the heat flux decreases according to the power law, and damage can be avoided when the distance between the fuel and the panel is twice the length of the panel. When the wind direction is east and south, to avoid damage to the electrical panel the distance must be increased by 1.5 times compared to no wind. The present scale model can be applied to any configuration where combustibles are located between two electrical panels, and can provide useful guidance for the design of redundant electrical panels.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1997.10a
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• pp.310-315
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• 1997

An extensive corrosion study was initiated by galvalume steel sheet manufacturing company to clarify the corrosion behavior of zinc and zinc and zinc-alloy coated automotive sheet steel in out panel and electrical application. Since the early 1980's the use of zinc and aluminum alloy coated steel for vehicular corrosion protection has increased drastically. This paper describes the evaluation of formability, weldability and painted corrosion performance of galvalume steel sheet. This paper presents an overview of the program and some initial test results on the weldability, lifetime of the electrode tip shape of the spot welding and corrosion protection. Galvalume steel sheet improved corrosion performance and spot weldability of galvalume steel has no problem for the variation of welding current. And tip lifetime was changed according to the influence of shape.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.2
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• pp.158-162
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• 2010

PSD is automatically opened and closed when subway train arrive on the station. This system was designed to control electric automatic system. These doors will provide passenger safety, energy saving and a good environment in subway. The monitoring and control systems of PSD are configured so that they can be operated in automatic mode in connection with ATO through the composite control panel in the station control room. The objective of this paper is to obtain high reliability that is essential for monitoring and control systems of PSD. The power supply is based on protection circuit using DC power bridge from two UPS. Also, stable communication system consists of CAN communication line redundancy and RF cross protection algorithm. Monitoring state display results show the validity of the proposed high reliability monitoring and control systems of PSD.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.2
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• pp.74-80
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• 1998

An extensive corrosion study was initiated by galvalume steel sheet manufacturing company to clarify the corrosion behavior of zinc and zinc-alloy coated automotive sheet steel in out panel and electrical application. Since the early 1980's the use of zinc and aluminum alloy coated steel for vehicular corrosion protection has increased drastically. This paper describes the evaluation of formability, weldability and painted corrosion performance of galvalume steel sheet. This paper presents an overview of the program and some initial test results on the weldability, lifetime of the electrode tip shape of the spot welding and corrosion protection. Galvalume steel sheet improved corrosion performance and spot weldability of galvalume steel sheet has no problem for the variation of welding current. And tip lifetime was changed according to the influence of shape.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.10a
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• pp.291-294
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• 2010

EPS 샌드위치 패널은 화재 시 치명적인 단점을 가지고 있다. 하지만 여전히 EPS 샌드위치 패널이 국내에 많이 사용되는 이유는 가격이나 시공성, 생산성에서 EPS를 대체할만한 물질이 아직 개발되지 않는 실정이다. 글라스 울 패널과 우레탄 폼 패널이 시장에 조금씩 유통되고 있지만 여전히 EPS 패널이 시장에서 70%이상을 차지하고 있다. 그래서 EPS를 코팅, 함침, 주입 등의 여러 가지 방법도 개발되고 있으나 그 중 가장 간단하고 가격이 낮고, 샌드위치패널에 적용이 가능한 코팅법에 의한 난연제의 배합설계와 비드와 난연제의 난연 등급에 따른 최적의 배합비를 제안하고자 한다.

• Journal of Radiation Protection and Research
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• v.46 no.3
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• pp.134-142
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• 2021

Background: From 2018 to 2020, the Expert Study on Public Understanding after the Fukushima Daiichi Nuclear Power Plant Accident (the Expert Study Group) identified and analyzed activities designed to promote public understanding of science and radiation since the Fukushima accident, and held discussions on how to achieve public understanding in the situation where public confidence has been lost, and how experts should prepare for dealing with the public. This panel session was held at the 53^rd meeting of the Japan Health Physics Society on June 30, 2020. Materials and Methods: First, three subgroup (SG) leaders reported their research methods and results. Then, two designated speakers, who participated as observers of the Expert Study Group, commented on the activities. Next, the five speakers held a panel discussion. Finally, the rapporteur summarized. Results and Discussion: SG leaders presented reports from researchers and practitioners in health physics and environmental risks who provided information after the Fukushima accident. During the discussion, experts in sociology and ethics discussed the issues, focusing on the overall goals of the three groups, local (personal) and mass communication, and ethical values. Many of the activities instituted by the experts after the accident were aimed at public understanding of science (that is, to provide knowledge to residents), but by taking into account interactions with residents and their ethical norms, the experts shifted to supporting the residents' decision-making through public engagement. The need to consider both content and channels is well known in the field of health communication, and overlaps with the above discussion. Conclusion: How to implement and promote the public engagement in society was discussed in both the floor and designated discussions. Cooperation between local communities and organizations that have already gained trust is also necessary in order to develop relationships with local residents in normal times, to establish an information transmission system, and to make it work effectively.

• Journal of the Korea Institute of Building Construction
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• v.23 no.6
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• pp.715-726
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• 2023

This study suggested that protective panels should be installed as sacrificial members as a safety design method for structures with potential explosions such as hydrogen charging stations to minimize direct damage to the structure and have resilience. To this end, the focus of the experiment is on quantitatively evaluating the impact of the structure when the protection panel is installed closely or spaced apart from the structure in a high-speed collision situation of the projectile. The experimental design used steel plates instead of concrete structural members mainly used in the past for excellent reproducibility, and the impact of structural members was compared and analyzed through deformation differences on the back of the steel plate. In addition, the impact of changes in the physical properties of the elastic body used as a separation material for the protective member and the difference in shock wave transmission time according to the protective member and the elastic body on the structural member was investigated.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.4
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• pp.707-718
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• 2001

The purpose of this study is to evaluate a newly developed protective suit with the fragments of grenade. The protection efficiency should be strengthened upon the degree of wound. The fragment weight of the used grenade was measured and the kinetic energy of the maximum speed of the fragments in the field test was 137.7J and this could be the protective efficiency test by the multitude fragments in less than 0.031g of the M16A1. The panel inserted to the new demining suit has protection rate of 100% within the distance of 1m and sample II has protection rate of 100% only beyond the distance of 5m. The test showed that the protection rate on the protective suit of the existing garment was comparatively high, however, the protection rate of the sleeve part was very low. The new demining suit through the research demand some complementary measures to lower the temperatures in ear, average skin temperatures, and the temperatures-humidity inside the clothing for summer climate condition, It showed that 30 minutes of rest on the clothing was difficult to go back to the original condition. But in winter climate condition, there was no problem in the temperature, humidity, and comfort to go back to the original condition during the rest and was better in warmth.