• 한국안전학회지
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• 제37권2호
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• pp.69-75
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• 2022

Fire-alarm systems are safety equipment that facilitate rapid evacuation and early suppression in case of fire. It is highly desirable that fire-alarm systems have low false-alarm rates and are thus reliable. Until now, researchers have attempted to improve detector performance by applying new technologies such as IoT. To this end, IoT-based fire-detection systems have been developed. However, due to scarcity of large-scale operational data, researchers have barely studied malfunctioning in fire-alarm systems or attempted to reduce false-alarm rates in these systems. In this study, we analyzed false-alarm rates of smoke/temperature detectors and unwanted fire-alarm signal patterns at K institution, where Korea's largest IoT-based fire-detection system operates. After analyzing the fire alarm occurrences at the institution for five years, we inferred that the IoT-based fire-detection system showed lower false-alarm rates compared to the automatic fire-detection equipment. We analyzed the detection pattern by dividing it into two parts: normal operation and unwanted fire alarms. When a specific signal pattern was filtered out, the false-alarm rate was reduced to 66.9% in the smoke detector and to 46.9% in the temperature detector.

• International Journal of Safety
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• 제10권1호
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• pp.36-40
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• 2011

Personnel maintaining or repairing the railway tracks or signaling facilities around tracks may experience the sensory disorder when doing maintenance works at the trackside of railway for long time. In this case personnel maintaining at the trackside may collide with the train since they cannot recognize the approach of motor-car although it approaches to the vicinity of maintenance workplace because of the sensory block phenomenon occurred due to their long hours of continued monotonous maintenance work. In order to prevent such motor-car accidents that may occur because railway track workers are unable to recognize the approaching train, the safety alarm equipment is developed to make the approaching motor-car send radio signals and bidirectional detection mechanism between approaching train and trackside personnel. It shows the possibility of utilization in various forms of safety equipment for workers only to the safety helmet to be worn by the maintenance workers while using the configuration of transmitting/receiving sides. In the paper it is represented new alarm equipment, which is the bone-anchored speaker-based safety helmet to be worn by the maintenance workers.

• International Journal of Safety
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• 제9권2호
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• pp.29-34
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• 2010

When doing maintenance works at the trackside of railway, the method which delivers information on approaching of train to maintenance workers through alarm devices such as the flag or indication light, etc., is being used by locating persons in charge of safety alarm in addition to the maintenance workers at fixed distances in the front and rear of the workplace. Workers maintaining at the trackside may collide with the train since they cannot recognize the approach of train although it approaches to the vicinity of maintenance workplace because of the sensory block phenomenon occurred due to their long hours of continued monotonous maintenance work. The clash or rear-end collision accidents between many maintenance trains called motor-cars can be occurred since there are cases where the signal systems for safe operation of motor-car such as track circuit etc. are blocked or not operated normally. We developed the new safety equipment for protection of trackside maintenance workers using radio frequency signals and bidirectional detection mechanism. The developed safety equipment must analyze the several operational mechanism for each different operation situations. In this paper the analysis results are represented.

• 해양환경안전학회지
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• 제17권3호
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• pp.265-268
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• 2011

본 논문에서는 해상 안개를 감지하여 선박 운항 시 선원들이 안전 운항을 할 수 있도록 알려주는 안개 경보 장치를 설계 및 제작하였다. 개발된 안개 경보 장치는 광전소자인 적외선 LED의 발광부와 수광부를 이용하여 센서부와 송수신 장치 모듈을 통합시켰으며, 수신 감도만을 이용하여 저전력 및 소형화하였다. 제작된 장치의 실험은 시정 1km 이내로 안개발생 기준을 습도 70 %로 하고 인공의 안개를 발생시켜 기준값을 초과하면 알람이 울리는 것을 실험에서 확인하였다. 개발된 장치를 선박에 적용할 경우, 짙은 안개에 따른 안전사고에 신속히 대응 할 수 있을 것이다.

• 한국철도학회논문집
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• 제12권5호
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• pp.738-743
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• 2009

철도의 선로변에서 선로나 신호설비의 유지보수 작업을 장기간 수행할 경우 감각차단 현상에 의해 작업 전후방에 열차가 접근하고 있어도 작업자가 열차를 인지하지 못하는 경우가 발생할 수 있다. 이러한 경우 작업자는 접근하는 열차와 접촉사고가 발생하여 사상사고가 자주 발생하게 된다. 이러한 철도선로변 유지보수 작업자의 사상사고의 저감을 위해 열차에서 특정 신호를 무선으로 주기적으로 전송하고 선로변의 작업자가 휴대하고 있는 단말장치에서 차상으로 부터의 무선신호를 수신하여 작업자에서 진동, 소리, LED 등 다양한 경보신호를 제공하여 사고를 예방하는 안전설비를 제안하였으며, 이를 바탕으로 안전경보장치를 개발하였고, 현장시험을 통해 그 적용성을 확인하였다.

• 해양환경안전학회지
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• 제11권1호
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• pp.17-22
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• 2005

선박의 항해 계기들의 기술이 발전됨에 따라 많은 장비들이 개발되고 있으나 여전히 인간과실에 의한 해양 사고는 지속적으로 발생하고 있는 현실에서, 인간과실에 의한 사고를 감소시키기 위하여 선교의 항해 계기들은 인간공학적적으로 배치, 설계되었는지가 많은 관심의 대상이 되고 있다 선교 내 여러 계기들의 알람장치는 선교 근무자에게 그 알람 장치가 주고자 하는 정보를 가능한 빨리 인식하고 정확한 정보를 전달할 수 있도록 설계되어야 하며, 국제적으로 인간공학적 선교를 위한 알람장치(Bridge Alarm Management System : BAMS)의 필요성이 논의 되고 있으나 아직 실질적인 설계방법 등에 대해서는 논의가 이루어지고 있지 않다. 따라서 본 논문에서는 선박의 여러 설비 중 선교의 알람장치에 관한 인간공학적 개념의 설계에 대하여 알아보고 현재 개발, 운용 중인 인간공학적 통합선교시스템(Integrated Bridge System :IBS)의 선교통합알람장치(Ergonomic Integrated Bridge Alarm Management System : EIBAMS)에 관한 개념적인 설계를 제안하고자 한다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(1)
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• pp.185-190
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• 1995

Conventional alarm system has many difficulties in the operator's identifying the plant status during special situations such as design basis accidents. To solve the shortcomings, an on-line alarm annunciator system, called dynamic alarm console (DAC), was developed. In the DAC, a signal is generated as alarm by the use of an adaptive setpoint check strategy based on operating mode, and time delay technique is used not to generate nuisance alarms. After alarm generation, if activated alarm is a level precursor alarm or a consequencial alarm, it would be suppressed, and the residual alarms go through dynamic prioritization which provide the alarms with pertinent priorities to the current operating mode. Dynamic prioritization is achieved by going through the system- and mode-oriented prioritization. The DAC has the alarm hierarchical structure based on the physical and functional importance of alarms. Therefore the operator can perceive alarm impacts on the safety or performance of the plant with the alarm propagation from equipment level to plant functional level. In order to provide the operator with the most possible cause of the event and quick cognition of the plant status even without recognizing the individual alarms, reactor trip status tree (RTST) was developed. The DAC and the RTST have been simulated with on-line data obtained from the full-scope simulator for several abnormal cases. The results indicated that the system can provide the operator with useful and compact information fur the earlier termination and mitigation of an abnormal state.

• 한국안전학회지
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• 제37권3호
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• pp.16-23
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• 2022

This study aims to provide a fundamental material for identifying fire and no-fire signals using the detection signal characteristics of IoT-based fire-detection systems. Unlike analog automatic fire-detection equipment, IoT-based fire-detection systems employ wireless digital communication and are connected to a server. If a detection signal exceeds a threshold value, the measured values are saved to a server within seconds. This study was conducted with the detection data saved from seven fire accidents that took place in traditional markets from 2020 to 2021, in addition to 233 fire alarm data that have been saved in the K institute from 2016 to 2020. The saved values demonstrated variable and continuous VC-Signals. Additionally, we discovered that the detection signals of two fire accidents in the K institution had a VC-Signal. In the 233 fire alarms that took place over the span of 5 years, 31% of smoke alarms and 30% of temperature alarms demonstrated a VC-Signal. Therefore, if we selectively recognize VC-Signals as fire signals, we can reduce about 70% of false alarms.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2005년도 춘계학술발표회
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• pp.1-6
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• 2005

선박의 항해 계기들의 기술이 발전됨에 따라 많은 장비들이 개발되고 있으나 여전히 인적과실에 의한 사고는 줄어들고 있지 않다. 이에 인적과실에 의한 사고를 줄이기 위하여 선교의 항해 계기들은 인간공학적적으로 배치, 설계되었는지가 관심의 대상이 되고 있다. 선교내에서의 여러 계기 중 알람장치는 선교 근무자에게 그 알람 장치가 주고자 하는 정보를 가능한 빨리 인식하고 정확한 정보를 전달할 수 있도록 설계되어야 하며, 국제적으로 인간공학적 선교를 위한 알람장치(Bridge Alarm Management System : BAMS)의 필요성이 논의 되고 있으나 아직 실질적인 설계방법 등에 대해서는 논의가 이루어지고 있지 않다. 따라서 본 논문에서는 선박의 여러 설비 중 선교의 알람장치에 관한 인간공학적 개념의 설계에 대하여 알아보고 현재 개발, 운용중인 인간공학적 통합선교시스템(Integrated Bridge System : IBS)의 선교통합알람장치(Ergonomic Integrated Bridge Alarm Management System : EIBAMS)에 관한 개념적인 설계를 제안하고자 한다.

• 동굴
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• 제87호
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• pp.8-13
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• 2008

The automatic firewall block and fire alarm system was embodied by using gas circuit and wireless communication equipment, using a smoke sensor (ST-QA1A) and RF Module. OR-CAD was also used for testing circuit system and experiment circuit after assembling circuit. As a result in experiment, the gas sensor detected well an imaginary smoke and worked reliably for driving action of firewall block motor and wireless warning alarm. Through the smoke sensitive perception from the fire, the warning alarm and the preventing fire propagation from the specific closed region were verified reliably. The gas sensor and RF module for firewall and fire alarm system were actually available.