• 한국전자통신학회논문지
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• 제12권4호
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• pp.525-532
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• 2017

본 논문에서는 자전거의 보호와 탑승자의 안전을 위하여 아두이노와 센서를 활용하여 시스템을 구성하였다. 리밋 스위치를 통하여 15 km/h이하, 15~30km/h, 30km/h 이상 속도에 따른 알림과 더불어 과속시 경고를 주고 실제 속도와 96.6% 일치하는 속도계를 구현한다. 또한 야간에 파악하기 힘든 5cm이하의 장애물을 감지하기 위하여 약 3m거리에서 초음파센서를 통해 이를 인지하고 경고를 한다. 자전거의 보호를 위하여 자물쇠 파손 시 사용자의 핸드폰에 메시지를 전송하고, Auto Lock System이 제어 되도록 한다. 사용자의 편의성을 고려하여 칼로리 소모를 알 수 있도록 어플리케이션을 제작하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권5호
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• pp.1597-1610
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• 2022

At present, the main method of high-speed train chassis detection is using computer vision technology to extract keypoints from two related chassis images firstly, then matching these keypoints to find the pixel-level correspondence between these two images, finally, detection and other steps are performed. The quality and accuracy of image matching are very important for subsequent defect detection. Current traditional matching methods are difficult to meet the actual requirements for the generalization of complex scenes such as weather, illumination, and seasonal changes. Therefore, it is of great significance to study the high-speed train image matching method based on deep learning. This paper establishes a high-speed train chassis image matching dataset, including random perspective changes and optical distortion, to simulate the changes in the actual working environment of the high-speed rail system as much as possible. This work designs a convolutional neural network to intensively extract keypoints, so as to alleviate the problems of current methods. With multi-level features, on the one hand, the network restores low-level details, thereby improving the localization accuracy of keypoints, on the other hand, the network can generate robust keypoint descriptors. Detailed experiments show the huge improvement of the proposed network over traditional methods.

• 한국전자통신학회논문지
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• 제10권10호
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• pp.1079-1086
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• 2015

본 논문은 안전 무결성 레벨이 4(: Safety Integrity Level 4)인 안전 관련 시스템에 적합한 출력 모듈의 구조를 설계하였고, 설계된 출력 모듈에 요구되는 정량적 목표치의 수준을 제시하였다. 특히 다양한 출력 방식 중에서 릴레이 출력 신호와 아날로그 신호로 구성된 출력 모듈이 안전 기능을 수행하는 시스템의 구성 요소인 경우를 적용하였다. 분석 방법은 FMEA(: Failure Modes and Effect Analysis), FTA(: Fault Tree Analysis) 방식을 이용하였다. 그 결과로 철도 응용 규격인 IEC 62425의 요구사항을 준수하는 SIL4 안전 관련 시스템의 출력 모듈의 구조와 고장빈도인 정량적 목표치를 제시하였다.

• 전기학회논문지
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• 제65권12호
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• pp.2030-2036
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• 2016

This paper presents a hardware development procedure of the ASB(Active Seat Belt) control system to comply with ISO 26262. The ASIL(Automotive Safety Integrity Level) of an ASB system is determined through the HARA(Hazard Analysis and Risk Assessment) and the safety mechanism is applied to meet the reqired ASIL. The hardware architecture of the controller consists of a microcontroller, H-bridge circuits, passive components, and current sensors which are used for the input comparison. The required ASIL for the control systems is shown to be satisfied with the safety mechanism by calculation of the SPFM(Single Point Fault Metric) and the LFM(Latent Fault Metric) for the design circuits.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.495-498
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• 2004

In this paper, the arc and flame characteristics of wires were studied during a short-circuit. The short-circuit angle between wires was fixed as $90^{\circ}$ and the experiments were conducted on bare copper wires by varying the diameter of wires. The arc and flame patterns were taken by a high speed imaging system. The direction of arc and flame was explained with Lorentz force. After the short-circuit experiment, the shapes of molten wires were analyzed by a stereo microscope. In the results of experiment, the arc and flame of wires showed particular patterns. The flame characteristics by the diameter of wires were analyzed using a HSIS. We could find out the arc characteristics of wires which were different by the diameter.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.48-49
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• 2005

한국형 고속철도시스템은 최고운행속도 350km/h로 주행하는 고속열차(시제열차 7량 편성)의 개발에 성공하여 현재 시운전 시험을 통해 신뢰성과 안정성을 검증하고 있다. 국내 기술로 새롭게 개발된 한국형 고속철도 시스템은 고속운행에 따른 엄격한 안전요구사항을 만족해야 하며, 특히 고속-대량의 수송수단으로서 승객의 안전을 최우선으로 하기 때문에 다른 어떠한 시스템보다 엄격한 안전확인 및 성능검증을 위한 철저한 시험평가 과정이 필요하다. 본 연구에서는 한국형 고속철도 시스템 개발에 적용한 안전설계 요건의 분석내용을 제시하고, 고속철도 차량시스템의 안전성능 요건을 입증하기 위한 성능시험 체계로서 구성품 시험, 완성차시험(단차 및 편성 시험) 및 시운전 시험으로 구분한 한국형 고속철도 차량시스템에 대한 성능시험기준안을 소개하고자 한다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.234-235
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• 2006

In this study, we experimented deterioration characteristics of PVC insulation wires for electrical apparatus by series arcing and analyzed the heat generation at the contacts of wires, glowing/growing process of copper oxide, waveforms of contact voltage, current, power dissipation, and so on. We found out that how glowing contacts and surface arcing can decompose PVC insulation and that subsequent series arc can lead to ignition. We expect that these results are useful for improving fire protection technology by providing a better understanding of how electrical fires can initiate.

• 한국전기전자재료학회논문지
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• 제32권4호
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• pp.349-355
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• 2019

A fire, be it caused intentionally or unintentionally, leads to economic loss and physical damage, and requires digestion. The number of fires is increasing yearly, and electrical fires account for more than 30% among the main causes of fires. Electric wires that catch fire typically employ silicone coatings; silicone has organic as well as inorganic properties. Silicon is a natural, nonexistent, synthetic product with numerous applications. In this study, a silicon rubber for application in wires was prepared by high-temperature vulcanization (HTV) with a Shore A hardness of 70. We report results for the flame retardancy test and the fire safety characteristics via inorganic analysis. For this, a quartz inorganic material was added to the wire specimen, and 18% powdered extinguishing agent ammonium phosphate and expanded vermiculite respectively. Thus, expanded vermiculite showed the best flame retardancy and fire safety characteristics.

• 자동차안전학회지
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• 제15권3호
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• pp.53-58
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• 2023

Defects in the vehicle itself were considered the biggest risk factor for traffic accidents as the electrical and electronic components of vehicles, which were not there before, increase. Therefore, the vehicles have been developed based on ISO 26262 (an international functional safety standard) which is focusing on functional defect safety evaluation of electrical and electronic component systems. However, in the future, as autonomous driving technology is applied, even vehicles without functional defects must be prepared for the dangerous traffic situation that may arise from exceptional or external factors. SOTIF (Safety Of The Intended Functionality) is a concept to prevent exceptional or external factors. The main objective of SOTIF is to decrease Unknown & Unsafe factors as much as possible by finding Known factors and Unsafe factors. In this study, Prescan provided SIEMENS, one of the autonomous driving simulators, is used to make scenarios of IGLAD traffic accident cases. From the simulation results, Unsafe & Safe cases were classified and analyzed to derive unsafe factors.

• 보건교육건강증진학회지
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• 제30권5호
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• pp.15-26
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• 2013

Objectives: To present the bases for health education on electronic cigarettes, we analyze the present state of electronic cigarettes. Methods: We applied descriptive study, reviewing the literature from domestic and foreign electronic databases such as National Discovery for Science Leaders and PubMed. Results: Electronic cigarette has been the subject of much controversy but very little study. I reviewed and summed up the definitions, device safety, health risk, smoking cessation effects, addiction, second hand smoke, and regulations of electronic cigarettes. Conclusion: Finally,I presented the evidence-based contents and desirable direction for health education about electronic cigarettes. The results suggested that the health educators focus on the potential addiction to electronic cigarettes, instead of the cessation effects.