• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.6
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• pp.1133-1138
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• 2010

We have developed an imaging radiometer system at W-band. The system consists of lens, reflector, 30-ch receiver array, scanner, and signal processor. One receiver consists of a dielectric rod antenna, a balun, LNA(low noise amplifier) and a detector. The system configuration requirements are described. Finally, we represent radiometer images to obtain through clouds, smoke, dust, and other obstructions which render visible and IR systems ineffective.

• Fire Science and Engineering
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• v.26 no.6
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• pp.51-56
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• 2012

The onset of fire on the International Space Station (ISS) is a critical problem that can threaten the life of crew members onboard and thus instantaneous fire detection and extinguishment technology has been considered as one of the most important aspects in the ISS operation. In the present study, a numerical analysis was performed to better understanding of the characteristics of smoke behaviors and detection in a pressurized module of the ISS using the NIST Fire Dynamic Simulator (FDS). Numerical results indicate that the smoke flow patterns under zero-gravity condition are clearly different from those under normal gravity condition. In addition, the results obtained from numerical simulations coupled with the PM internal flows are expected to provide basic and useful information in designing the microgravity fire detection devices and establishing in fire response protocol for astronauts or the crew members.

• Journal of Korean Association for Spatial Structures
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• v.10 no.2
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• pp.135-145
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• 2010

The objective of this study is to draw basic data for the application of the fire protection planning for the future plan large enclosure buildings in Korea through an analysis of its characteristics by case studies of the domestic and foreign large scale gymnasiums. In this study, domestic building codes for the fire protection are investigated and fire detection systems, fire extinguishing systems, smoke control systems and evacuation systems of three large scale gymnasiums located at Korea and eight foreign countries are compared and analyzed. The results of this study show that infrared light fire detection system and flame detector for spacial characteristics are potentially used in fire protection systems of large scale gymnasiums: dry type sprinkler and sprinkler water gun are adopted in fire detection system; and smoke accumulation system is widely utilized in smoke control system.

• Fire Science and Engineering
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• v.33 no.1
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• pp.85-91
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• 2019

This study evaluated the fire detection performance of an automatic fire extinguishing system for road tunnels, which combines flame wavelength detection technology with flame image detection technology. This fusion technique to improve the fire detection capability can reduce the damage caused by the fire suppression by locating the fire source in the fire and discharging the pressurized water only at the fire source. Experiments were conducted to determine the position of a fire source when a $70cm{\times}70cm$ target was placed at a distance of 15 m, 20 m, 25 m, 30 m, and 35 m, respectively, in a situation where there is a flame and smoke in a tunnel. The performance of the ultraviolet and triple wavelength infrared (IR3) sensors was attenuated due to the interference of thick smoke. In addition when the flame was blocked by thick smoke, the image sensor sensed the smoke and emitted a fire signal.

• Journal of Sensor Science and Technology
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• v.23 no.5
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• pp.342-348
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• 2014

This paper introduced a novel multi-gas sensor detector with simple signal processing algorithm. This device was evaluated by investigating the characteristics of combustible materials using fire-generated smell and smoke. Plural sensors including TGS821, TGS2442, and TGS260X were equipped to detect carbon monoxide, hydrogen gas, and gaseous air contaminants which exist in cigarette smoke, respectively. Signal processing algorithm based on the difference of response times in fire-generated gases was implemented with early and accurately fire detection from multiple gas sensing signals. All fire experiments were performed in a virtual fire chamber. The cigarette, cotton fiber, hair, polyester fiber, nylon fiber, paper, and bread were used as a combustible material. This analyzing software and sensor controlling algorithm were embedded into 8-bit micro-controller. Also the detected multiple gas sensor signals were simultaneously transferred to the personnel computer. The results showed that the air pollution detecting sensor could be used as an efficient sensor for a fire detector which showed high sensitivity in volatile organic compounds. The proposed detecting algorithm may give more information to us compared to the conventional method for determining a threshold value. A fire detecting device with a multi-sensor is likely to be a practical and commercial technology, which can be used for domestic and office environment as well as has a comparatively low cost and high efficiency compared to the conventional device.

• International journal of advanced smart convergence
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• v.6 no.1
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• pp.76-81
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• 2017

This paper presents a low cost and flexible IoT enabled smart LED controller using Arduino that is used for emergency exit signs. The Internet of Things (IoT) is become a global network that put together physical objects using network communications for the purpose of inter-communication of devices, access information on internet, interaction with users as well as permanent connected environment. A crucial point in this paper, is underlined on the potential key points of applying the Arduino platform as low cost, easy to use microcontroller with combination of various sensors applied in IoT technology to facilitate and establishment of intelligent products. To demonstrate the feasibility and effectiveness of the system, devices such as LED strip, combination of various sensors, Arduino, power plug and ZigBee module have been integrated to setup smart emergency exit sign system. The general concept of the proposed system design discussed in this paper is all about the combination of various sensor such as smoke detector sensor, humidity, temperature sensor, glass break sensors as well as camera sensor that are connected to the main controller (Arduino) for the purpose of communicating with LED exit signs displayer and dedicated PC monitors from integrated system monitoring (controller room) through gateway devices using Zig bee module. A critical appraisal of the approach in the area concludes the paper.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.04a
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• pp.150-151
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• 2013

화재감지기는 연기감지기는 이온전류의 변화량을 감지하는 이온화식 연기감지기와 발광부와 수광부로 이루어진 챔버내에 연기에 의한 광량의 변화를 감지하는 광전식 연기감지기로 구분된다. 국내에서는 광전식 연기감지기가 더 많이 사용되고 있는데 이러한 광전식 연기감지기의 챔버내에 이물질이 침입하게 되면 비화재보를 발생시키게 된다. 본 논문은 연기감지기의 연기감지 챔버에 대한 비화재보를 감소시키기 위한 신뢰성 시험에 대하여 논한 연구이다. 본 연구에서는 광전식 연기감지기의 신뢰성을 검증하는 방법으로 UL 268 등에 규정되어 있는 먼지, 즉, 분진에 대한 신뢰성을 검증방법을 제시하였다. 먼지에 대한 신뢰성 검증을 보다 적절하게 하기 위하여 분진챔버로 분진을 반복적으로 폭로됨에 따른 감도성능 변화를 분석하는 방법이 필요할 것으로 사료된다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7964-7970
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• 2015

In enclosed areas such as railway tunnels, the heat and smoke generated by a fire can pose a tremendous risk to the life of passengers. To prevent or mitigate such scenarios, fire detectors are installed for early fire detection. This numerical study is preformed for establishing the method of detecting performance of fire detectors installed on railway tunnels. Numerical analysis are conducted using the fire dynamics simulator, developed by the NIST. The temperature of the tunnel walls is determined using the assumed exterior structure of the tunnel. In addition, the detection times of detectors installed at different locations in the tunnel are obtained for different sizes of the fire source, and the results are compared and analyzed.

• Journal of Korean Institute of Fire Investigation
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• v.6 no.1
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• pp.49-66
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• 2005

The purpose of this study is to present reference data to be considered in designing fur the fire safety of atrium buildings. This study deals with the characteristics of atrium buildings in the fire safety aspect, analysis of fire examples and foreign fire codes of atrium space. And con-crete factors to be consigning fur the fire facilities of atrium buildings are presented. Recently many atrium spaces have been built in Korea. They provide new experience of space with resident and pedestrians. However, because of the lack of knowledge in design principle and disaster prevention, large loss of lives is expected in an emergency situation. cion. Therefore safety ensuring from the case is urgently needed. The following is the summary on the standard of effective fire facilities for the atrium. 1. The smoke control. inside atrium must use the machine ventilation in the atrium. 2. It is desirable to divide the section between atrium and nearby living room by anti-smoke screen in order to prevent damage by smoke when fire break out. 3. It is desirable to instill an excellent fire detector like infrared light detector as a replacement of old one. 4. It is desirable to transfer from closed operating sprinkler to fire-cycle sprinkler equipment or ablative sprinkler when the height is lower than 20m.

• Fire Science and Engineering
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• v.33 no.5
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• pp.55-60
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• 2019

The occurrence of fire in rack-type warehouses may either lead to the warehouses getting entirely burned up or collapsing. This can be attrubuted to the high height of rack-type warehouses, in which combustibles are generally vertically stacked. These characteristics make it difficult to detect a fire early; because detectors are installed on the ceiling, these fires cannot be extinguished at an early stage. In this study, the flow of heat and smoke generated by a fire in a rack-type warehouse was analyzed using a fire dynamic simulator. Through this analysis, the optimal installation conditions of fire detectors for the early detection of fire in rack-type warehouses were confirmed. The analysis results confirmed that complex detection of heat and smoke is required for the early detection of fire in rack type warehouses. Furthermore, it was found that fixed temperature detectors are not suitable for these warehouses, resulting in the need to install heat-smoke hybrid detectors at every three rack levels.