• Journal of the Korean Institute of Gas
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• v.18 no.1
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• pp.68-74
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• 2014

In this study, to analyze the impulsive response of a helmet, a simple vibration model is presented. Based upon the experimental data and the simulation results, an equivalent one degree of freedom vibrational system is adapted, and transient impulsive responses are analysed to investigate the influence of engineering parameters such as damping, natural frequency, and impact velocity on the impulsive response of the helmet. Maximum gravitational acceleration reduces as the damping factor value increases. When the damping factor value is around 0.6 or larger, the maximum acceleration does not change. With respect to the natural frequency and the impact velocity, it increases linearly. The relationship between head injury criterion(HIC) and maximum gravitational acceleration is also presented. The scheme of this study is expected to be utilized to economize the design process of high quality helmets.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.6
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• pp.101-108
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• 2016

This study was initiated to minimize head injuries, which is the largest cause of increased external activity, traffic accident injuries, and death. We developed a low cost airbag that can be covered by a safety helmet based on consumer needs. The results of the survey showed that safety is the most important aspect of consumers' safety helmets. It also predicted that increasing the weight would present the biggest problem. Curved airbag cushion parts that can be attached to a helmet and the sensor part of a block type were designed. Impact analysis was performed by specifying the pressure inside the airbag and the volume of the airbag as variables.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.386-389
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• 2016

The number of cyclists is on the steady growing for leisure, sports and transportation with the increasing interest in health and environment. However, the number of cycling accidents is also increasing steadily due to the lack of safety awareness and regulations. Focusing on these issues, we propose and develop the smart LED cycling helmet in order to reduce a risk of cycling accident. To provide the motion information of the bicycle for others, we attach the LEDs on the helmet and control the LED lights using Arduino. The motion information is displayed on the LED helmet by using sensors of the smartphone. Communication between Arduino and the smartphone is performed through Bluetooth.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.332-339
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• 2020

This study was a prior study to establish the shelf life of bulletproof helmets, considered the aging factor of bulletproof helmets. To estimate the aging factor of bulletproof helmets, we established a hypothesis that the 'temperature' factor would have the greatest impact on the shelf life of the bulletproof helmet, considering the environmental treatment of the American army's bulletproof helmet's materials. To verify the hypothesis, high temperature acceleration environmental treatment of bulletproof helmets was performed, and the Arrhenius formula was applied to calculate the shelf life. The study result confirmed the negative correlation between bulletproof performance and high temperature, and the influence of temperature as an aging factor was not significant by deriving life by using the Arrhenius model. The limitation of this study is that we couldn't obtain enough samples due to the specificity (miliary supplies) of the test subjects. However, given that the life-related research on bulletproof helmets has not been carried out, this research has great implications and could be used as a reference for improving the Korean Army's bulletproof helmet specifications.

• Journal of the Ergonomics Society of Korea
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• v.34 no.5
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• pp.501-517
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• 2015

Objective: The aim of this study was to investigate the technology trend on developing helmets based on the analysis of Korean, US, European and PCT patents. Background: The usage of the personal protective equipment such as the safety helmet would be essential for preventing injuries and reducing the severity of injuries depending on the type of activity and the exposed environment. Method: Database of WIPSON was used for searching the patents. The objects were the Korean, US, European and PCT patents registered or opened from January 2011 to December 2014. The keyword to investigate was helmet, and International Patent Classification (IPC) was used for investigating the technology trend of the patents. Results: The cases of US patents annually increased, but the cases of European patents decreased. US patents belonged to all sections but Korean and European patents and PCT patents did not. The largest number of IPC, to which four areas' patents belonged, was 'Headwear' and the second largest one was 'Hygiene'. In the subgroup level, the most common largest subgroups were 'Parts, details or accessories of helmets' and 'Masks, shields, or hoods for welders'. Korean patents had the lowest ratio of single_IPC at 11%, but the ratios of single_IPC for US and European patents were 52%, respectively. 'Human necessities', 'Mechanical engineering', 'Physics', and 'Electricity' were used as a single_IPC, but lower levels of 'Performing operations', 'Chemistry', 'Textiles' and 'Fixed constructions' were used as multi_IPC. Most main applicants had patents which belonged to 'Human necessities'. Conclusion: The cases of US patents annually increased unlike others. The common technologies for creating the helmet were Parts of helmets under Headwear and Shields for welders under Hygiene. Many Korean patents tended to be categorized as multi_IPC, different from others. Application: To know the technological characteristic of patents would be helpful to initial stage developers.

• Archives of Craniofacial Surgery
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• v.12 no.1
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• pp.28-32
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• 2011

Purpose: A cranioremodeling helmet for correcting plagiocephaly was recently developed. However, no discrete objective methods to evaluate how the deformity is being corrected have been developed. We have established an easy and cost-effective method that can be used not only to show the correction process, but can also be used by physicians to assess the degree of plagiocephaly two-dimensionally. Methods: For two-dimensional evaluation, a length of malleable memory wire (2 mm in diameter) resembling "Sun-Wukong's headband" was placed on the patient's head. The wire around the patient's head was positioned on a plane including points 1 cm above the eyebrow and 1 cm above the auricle. The wire was placed on a sheet of paper and the outline was marked using pens of various colors during each visit. The degree of plagiocephaly correction could then be shown to the patient's parents at every consultation. Results: The method established by the present study easily shows the horizontal cross-section transformation of the head, illustrates plagiocephaly correction by the helmet, and shows the degree of correction in a two-dimensional manner. Conclusion: A soft-shell helmet is widely used for correcting plagiocephaly. However, evaluating the effectiveness of the helmet has been determined in a subjective manner, and a more objective method is now in demanded. Our study found that a "Sun-Wukong's headband" wire can accurately measure two-dimensional changes. Future studies will be required to identify landmarks needed for assessing plagiocephaly correction.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.4
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• pp.529-535
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• 2020

It is important to secure the driver's external field view in armored vehicles surrounded by iron armor for preparation for the enemy's firepower. For this purpose, a 360 degree rotatable surveillance camera is mounted on the vehicle. In this case, the key idea is to recognize the head of the driver wearing a helmet so that the external camera rotated in exactly the same direction. In this paper, we introduce a method that uses a MEMS-based AHRS sensor and a illuminance sensor to compensate for the disadvantages of the existing optical method and implements it with low cost. The key idea is to set the direction of the camera by using the difference between the Euler angles detected by two sensors mounted on the camera and the helmet, and to adjust the direction with illuminance sensor from time to time to remove the drift error of sensors. The implemented prototype will show the camera's direction matches exactly in driver's one.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.4
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• pp.723-730
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• 2023

Due to the recent development of battery technology, various types of means of transportation such as electric kickboards, Segways, and electric bicycles have emerged, which can be defined as Personal Mobility. In this paper, as the incidence of safety accidents increases due to the increase in the number of users of Personal Mobility, safety helmet devices that strengthen safety capabilities and peripheral recognition functions were studied. In order for the helmet to send a safety signal, Arduino was used as a base to set the value of the sensor according to changes in distance and angle using the ultrasonic sensor to minimize errors and ensure smooth recognition. In addition, a gyro sensor was used to turn on the direction indicator according to each slope. Using a CDS sensor, the LED is designed to turn on when it goes below 150 lux at night. Finally, it is possible to check whether a helmet is worn within 5cm, and when driving at an average speed, the direction indicator light is turned on at 10 degrees, and the LED is turned on at less than 150 lux.

• Journal of the Institute of Convergence Signal Processing
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• v.24 no.2
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• pp.82-89
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• 2023

Due to the characteristics of ship structure, the compartment structure is complicated and narrow, so safety accidents frequently occur during the work process. The main causes of accidents include structural collisions, falling objects, toxic substance leaks, fires, explosions, asphyxiation, and more. Understanding the on-site conditions of workers during accidents is crucial for mitigating damages. In order to ensure safety, the on-site situation is monitored using CCTV in the ship, but it is difficult to prevent accidents with the existing method. To address this issue, a smart safety helmet equipped with location identification and voice/video communication capabilities is being developed as a safety technology. Additionally, the smart safety helmet incorporates environmental sensors for temperature, humidity, vibration, noise, tilt (gyro sensor), and gas detection within the work area. These sensors can notify workers wearing the smart safety helmet of hazardous situations. By utilizing the smart safety helmet and environmental sensors, the safety of workers aboard ships can be enhanced.

• Journal of the Korean Society of Safety
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• v.28 no.5
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• pp.83-89
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• 2013

Occupational Safety and Health Act provides that industrial safety helmets are personal protective equipment(PPE) to protect heads against falls from a height. Relevant domestic regulations are distinguished and different from other countries' cases. This study investigated industrial safety helmet's protective purposes and characteristics related to falls and the notion of fall prevention. A comparative analysis of regulations on safety helmets and fall prevention as well as standards on safety helmet's impact test requirements is followed by a literature review. It is also suggested that the term "fall" related to safety helmets should be changed to "impact on the upper part of head" in domestic regulations and standards.