• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.199-202
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• 2001

An elevator system, which is essential equipment for vertical movement of an object, as a property of building, has been driven by various expenditures and purposes. Since developing electrical control technology, control system are highly developed. The elevator system has expanded widely, but a data accuracy acquisition technique and safety predict technique for securing system safety is still at a basic level. So, objective verification for elevator confidence condition requires an absolute accuracy measurement technique. Therefore, this study is executed in order to acquire a method of depending on sense of a manager with simple numeric measurement data, and to construct a logical, analytical foresight system for more efficient elevator management system. As an artificial intelligence for diagnosis, the fuzzy inference algorithm is used for foreseeing the system in this thesis, because the fuzzy algorithm is the most useful method for resolving subjective ideas and a vague judgment of humans. The fuzzy inference algorithm is developed for each sensor signal(i.e. vibration, velocity, current).

• Journal of the Korean Society of Safety
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• v.33 no.1
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• pp.35-40
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• 2018

This research aimed to develop an leakage detector of analyzing the electric potential generated from the electric leakage of electric equipment of the fountain. To accomplish this goal, the potential gradient was analyzed against path 1 ~ path 4; this was done by taking the lighting of a fountain as the electric leakage point based on code analyses in Korea and other countries. Lighting 1 was taken as the electric leakage point, and the earthing point was set against lightings(2~3). It appeared that the allowable touch voltage against the 1 type(under 2.5 V) exceeded 60.0%. Therefore, the lighting of fountain turned out to be the most dangerous point, and electric shock could be formed by the electric leakage of electric equipment in underwater as well as by the lighting. An leakage detector was developed based on this risk; this detector is capable of analyzing the electric potential of a electric equipments of the fountain in underwater. Then, a verification test was carried out. This leakage detector can be used to measure electric potential in various submerged areas such as swimming pools, flooded spaces, and fountains.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.1
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• pp.61-72
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• 2018

Objectives The authors propose a new checklist model adapted for safety miniscalpel acupuncture procedure of cervical and lumbar spine. Methods On the basis of available literature and expert opinion, a prototype checklist was developed. The checklist was adapted on the basis of observation of daily practice. Results The checklist has three parts: 1. prevention and management of healthcare associated infections, 2. verification list before and after miniscalpel acupuncture treatment, 3. adverse event monitoring after procedure. We presented a summary checklist based on the above contents. Conclusions We propose the first patient safety checklist for minicalpel acupuncture treatment of cervical and lumbar spine. The checklist will be complemented using further research methodologies.

• Journal of the Korea Safety Management & Science
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• v.18 no.3
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• pp.33-45
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• 2016

Construction sites have gradually become bigger and bigger according to Korea economic growth. Also use of tower crane and other heavy equipment has been increased. The increased use of heavy equipment like tower crane is leading to fatality incident. This study will verify hazards to influence tower crane incident through structural and positive verification and find which hazard influence incident risk. The result of this study is as follows. First, while there is a significant difference between safety managers and tower crane operators for working environment, safety management, personal manage among risk factors, we can not find any evidence on the difference in perception of tower crane incident risk between them. Second, task manage risk and personal manage risk has a significant positive effect on perception of tower crane incident risk. Third, while site environment risk has a significant positive moderating effect of task type between risk factors and perception of tower crane incident risk, personal environment risk has a significant negative moderating effect between them.

• Journal of the Korea Safety Management & Science
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• v.9 no.4
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• pp.11-16
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• 2007

최근 들어 산업현장 뿐만 아니라 농어촌에도 자동화가 가속화되면서 작업자의 안정성과 편리성을 높이기 위한 다양한 방안이 제시되고 있지만 여전히 농업현장에서 대부분의 작업들이 부적절한 자세로 수행할 수밖에 없는 경우가 자주 발생한다. 본 연구는 쪼그려 앉는 작업자세가 요구되는 각종 농작업에 있어서 적합한 높이의 작업용 좌대를 제공함으로써 부적절한 작업자세를 개선하여 노동 강도를 경감시킴과 동시에 작업능률 향상과 요통 등 근골격계질환을 감소시켜 작업자의 건강과 안전을 증진시키는데 목적을 두었다. 이를 위하여 농작업에서 행해지는 쪼그려 앉는 여러 자세에 있어서 재배작물의 높이에 따라 적절한 작업용 좌대의 높이를 실험을 통하여 규명하였다. 연구결과 쪼그려 앉아 작업을 수행해야 하는 유사한 작업이라도 작업위치에 따라 쪼그려 앉는 작업용 좌대의 적합한 높이는 달라져야 한다는 것을 발견하였다. 즉 작업위치가 5cm 이하이면 작업용 좌대 높이는 10cm가 적절하며 작업위치가 20cm이면 15cm, 작업위치가 40cm이면 20cm가 적절함을 알 수 있었다. 이와 같은 결과를 농작업에 적용한다면 작업조건이 향상되어 편안하고 안전한 자세로 작업을 할 수 있기 때문에 허리, 어깨, 다리 등의 근골격계 질환을 감소시킬 수 있으며 인력작업에 따른 무리한 힘의 소모를 감소시켜 노동력 절감은 물론 생산성 향상을 가져올 수 있다고 판단된다.

• Journal of Applied Reliability
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• v.8 no.2
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• pp.101-111
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• 2008

Good diagnostics improves both the safety and system unavailability of digital safety systems. The measure of a diagnostic capability is called the Coverage Factor. Because the Failure Modes, Effects and Diagnostic Analysis (FMEDA) provides information on the failure rates and failure mode distributions necessary to calculate a diagnostic coverage factor for a component, the FMEDA can be used as a useful tool to calculate it. Through performing FMEDA on a digital signal processor (DSP) board used in a digital safety system, it is shown that some components of the DSP board can be replaced or improved to satisfy the required diagnostic coverage. That is, the FMEDA can serve as a useful verification tool to design a diagnostic capability for the DSP board.

• Structural Engineering and Mechanics
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• v.76 no.3
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• pp.367-378
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• 2020

This paper presents a new design concept for ocean nuclear power plants (ONPPs) using a tension leg platform (TLP). The system-integrated modular advanced reactor, which is one of the successful small modular reactors, is mounted for demonstration. The authors define the design requirements and parameters, modularize and rearrange the nuclear and other facilities, and propose a new total general arrangement. The most fundamental level of design results for the platform and tendon system are provided, and the construction procedure and safety features are discussed. The integrated passive safety system developed for the gravity based structure-type ONPP is also available in the TLP-type ONPP with minor modifications. The safety system fully utilizes the benefits of the ocean environment, and enhances the safety features of the proposed concept. For the verification of the design concept, hydrodynamic analyses are performed using the commercial software ANSYS AQWA with the Pierson-Moskowitz and JONSWAP wave spectra that represent various ocean environments and the results are discussed.

• Journal of Aerospace System Engineering
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• v.15 no.4
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• pp.64-74
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• 2021

Unmanned Aircraft Systems (UAS) are rapidly emerging not only as a key military power, such as surveillance and reconnaissance for military purposes but also as a new air transportation means in the form of Urban Air Mobility (UAM). Currently, airworthiness certification is carried out focused on the verification of technical standards for flight safety suitability of aircraft design in accordance with the Military Aircraft Flight Safety Certification Act and does not employ the model for operational risk assessment for mission areas and airspace. In this study, in order to evaluate the risk of the mission area from the perspective of the UAS operator, a risk assessment simulation has been conducted by applying the Specific Operations Risk Assessment (SORA) model to the operating environment of the Korean military UAS. Also, the validity of the SORA model has been verified through the analysis of simulation results, and a new application plan for airworthiness certification of the military unmanned aerial system has been presented.

• Journal of the Korean Society of Safety
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• v.38 no.6
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• pp.9-15
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• 2023

Hydrogen is gaining attention as a sustainable and renewable energy source, potentially replacing fossil fuels. Its high diffusivity, wide flammable range, and low ignition energy make it prone to ignition even with minimal friction, potentially leading to fire and explosion risks. Workplaces manage ignition risks by classifying areas with explosive atmospheres. However, the effective installation of a blast wall can significantly limit the spread of hydrogen, thereby enhancing workplace safety. To optimize the wall installation of this barrier, we employed the response surface methodology (RSM), considering variables such as wall distance, height, and width. We performed 17 simulations using the Box-Behnken design, conducted using FLACS software. This process yielded two objective functions: explosion likelihood near the barrier and explosion overpressure affecting the blast wall. We successfully achieved the optimal solution using multi-objective optimization for these two functions. We validated the optimal solution through verification simulations to ensure reliability, maintaining a margin of error of 5%. We anticipated that this method would efficiently determine the most effective installation of a blast wall while enhancing workplace safety.

• Journal of Auto-vehicle Safety Association
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• v.16 no.1
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• pp.55-61
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• 2024

The advancement of autonomous driving technology is expected to transform cars beyond mere transportation into multifunctional spaces for relaxation and entertainment. As autonomous driving technology becomes more sophisticated, with no need for direct driver control, the interior space of vehicles is anticipated to be utilized for various purposes. Consequently, the importance of car seats, the component most frequently interacted with by passengers during travel, is expected to significantly rise. However, existing car seats are designed according to a seated posture, necessitating verification for passenger safety and seat structure considerations in the context of autonomous driving, where comfortable postures may differ. For these reasons, it is anticipated that the seats of future autonomous vehicles will evolve with the incorporation of additional safety and convenience features. In this study, a three-axis car simulator was employed to investigate seat angles for comfortable postures of passengers in autonomous driving scenarios. Representative postures were identified to enhance passenger convenience. Furthermore, functional design factors contributing to passenger comfort were applied to conduct seat design, seat structure, and collision analysis, with an analysis of the interrelationships among design factors.