• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.611-613
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• 2017

This paper proposes a new method to reduce the overhead by pilots for single carrier frequency domain equalization (SC-FDE) transmission. In the conventional SC-FDE transmission structure, the overhead by transmitting pilot are heavy because the pilot are transmitted at every SC-FDE block. The proposed SC-FDE structure has fewer pilots and many SC-FCE blocks are transmitted between pilots. The channel estimation and equalization is performed at the pilot period and the channels between pilots are estimated through linear interpolation. This reduces the pilot overhead by reducing the pilot transmission compared with the conventional structure, and enables reliable channel estimation and equalization.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.2
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• pp.44-54
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• 2022

An empirical analysis was conducted on the workload of helicopter pilots flying in high-risk flight environments such as ground obstacles and weather effects at low altitudes. To evaluate the workload, an independent sample t-test was performed using the NASA-TLX evaluation method most suitable for the aviation field, and the workload score was calculated by applying the analytical stratification method (AHP) to compare and analyze private and commercial pilots. There is a significant difference in mean between private and commercial pilots and the result of work load was obtained over 70%. This paper studied the 'surprise and startle effect' on the helicopter field for the first time. In the future, it is intended to contribute to the safe operation of helicopters by presenting a method for effective safety management by utilizing it in the field of education and training for helicopter pilots and providing basic data for preventing accidents caused by human error.

• Korean journal of aerospace and environmental medicine
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• v.31 no.3
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• pp.64-67
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• 2021

When the COVID-19 crisis hit air transport, the whole aviation industry was affected. The change in the behavior of passengers following the COVID-19 crisis, travel restrictions and the ensuing economic crisis have resulted in a dramatic drop in demand for airline services. The COVID-19 pandemic, with all its associated consequences, has had a significant impact on the mental health and well-being of pilots, which could impact operational safety. As the number of international flights has decreased, pilots are exposed to high levels of psychological stress such as job instability, reduced income and increased risk of infection during flight work. Psychological stress lowers work performance and threatens aviation safety. The pilot needs mental health management during the COVID-19 pandemic, but psychological support is weak. For pilot mental health management, it is important to raise awareness about mental health and to continuously respond. To this end, it is necessary to foster a safe and trustworthy culture in which mental health issues are discussed freely and solved together without hiding them. They should also support the establishment of a peer support program that is easily accessible and that allows pilots to discuss their issues with confidence.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.4
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• pp.126-132
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• 2023

During the COVID-19 pandemic, there have been many changes in the aviation industry as a whole. Passenger traffic has decreased, but on the contrary, the international transport demand for cargo planes has never been higher. Due to their geopolitical location when flying to major cities around the world, Korea's international pilots are bound to have relatively more jet lag-causing routes than their American or European-based pilots. Through this study, we tried to analyze the degree of fatigue and fatigue weighting factors according to operating conditions for domestic pilots. As a result of the study, the following conclusions were drawn. Despite the variety of models, routes, and fatigue between individuals, it was found that the 3 Pilot operation route was concentrated as a representative fatigue route. Most of the individual fatigue improvement request sections showed higher fatigue as the night flight section was longer among the 3Pilot routes for more than 12 hours, and 43 out of 90 participants (Korean Air pilots) focused on 3Pilot (two captains and one pilot) as fatigue-intensive operating conditions. Therefore, it proposes an improvement in the system of applying 12-hour unification standards according to Korea's geopolitical international operating conditions and time difference standards.

• Journal of Advanced Navigation Technology
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• v.25 no.6
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• pp.466-475
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• 2021

Airport-related laws restrict the installation of lights that obstruct the identification of airport lights or cause glare to pilots and controllers around the airport. However, with regard to the glare that lights give to the pilot or controller, it is only judged whether there is a limit based on a qualitative judgment, and a quantitative review has not been made. Therefore, in this study, visual disturbances that may occur to pilots and controllers due to large lighting facilities around airports during nighttime flight operation were quantitatively calculated and confirmed through disability glare, object recognition, and identification obstruction. And based on this study, it was suggested to supplement the related system to prevent the visual impairment of pilots and controllers caused by lighting facilities.

• Journal of the Ergonomics Society of Korea
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• v.36 no.5
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• pp.535-543
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• 2017

Objective: This study was designed to identify factors affecting pilots' +Gz tolerance recovery from +Gz induced exhaustion. Background: +Gz tolerance of pilots has been considered as a crucial factor to fly the modern high performance fighter aircrafts. However, the factors affecting pilots' G-tolerance recovery from +Gz induced exhaustion have not been examined in the acceleration research community. Method: A centrifuge profile consisting of a high +Gz run for pilot's exhaustion and a low +Gz run for pilot's recovery and another high +Gz runs for pilot's second exhaustion was designed. The subjects' +Gz tolerance recovery ratio was measured by ratio of second high +Gz run time to the first high +Gz run time. The subjects' +Gz tolerance recovery rate was measured by dividing the subjects' +Gz tolerance recovery ratio by the low +Gz run time. The subjects' G-tolerance recovery rate was analyzed with respect to the subjects' personal factors including subjects' anthropometric and physiologic characteristics, flight time, flying aircraft type and so on. Results: The subjects' previous three-month flight hours (r=-0.336, p=0.039), six-month flight hours (r=-0.403, p=0.012) and one-year flight hours (r=-0.329, p= 0.044) correlated with the subjects' G-tolerance recovery rate. Conclusion: The subjects' G-tolerance recovery rate is clearly related to the subjects' previous flight hours. However, the subjects' anthropometric and physiologic characteristics do not show any statistically significant correlation with the subjects' G-tolerance recovery rate. Application: This research provides a safety critical insight to aviation community by identifying the factors to affect the gravity-induced loss of consciousness (GLOC) of pilots.

• Journal of Advanced Navigation Technology
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• v.20 no.6
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• pp.580-587
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• 2016

In the purpose of suggesting the necessity and proper method of providing the standard reference material for acquiring the aircraft pilot license, this study provides the FAA and ROKAF case study, and positively analyzes the materials of 178 pilots and student pilots who acquired the aircraft pilot license. The result of case study shows that compared to the case of Korea which the restriction on the standard reference material providing exists, the FAA(Federal Aviation Administration) and ROKAF are currently providing the standard reference material. Additionally, the result of positive analysis indicates the fact that the necessity of standard reference material providing is well recognized and its importance also found to be remarkably high. These results represent that the standard reference material providing is necessary for training competent aircraft pilots. Also, this will mitigate the current shortage of aircraft pilots due to the rapid growth of air transportation industry, and this will play an important role in preventing diverse aircraft-related accidents.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.1
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• pp.137-147
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• 2017

An accident during pilotage may cause several problems such as crippling the harbour function, environmental disruption, loss of life. Since the pilot plays an important role in the safe operation of the port, securing their safety is directly connected to the vessel's safety coming into port in Korea. Pilotage service is offered on request without distinction of day and night. And traveling by helicopter and boarding/disembarking using a pilot ladder from and to a pilot boat have a high risk of falling into the sea. So, pilots can fall into the sea while boarding/disembarking from ship which can lead to serious injury by cardiac arrest. A number of pilots have died or severely injured due to fall from the pilot ladder during embarkation and disembarkation up to now. Current safety measures at embarkation and disembarkation required by pilotage act and IMO resolutions could not prevent all the pilot related accidents. Therefore, to prevent pilot accident during boarding/disembarking from ship, it is necessary to include safety training requirement for new pilots under the requirements for licensing of pilotage act. It is also necessary to compel pilots to take necessary personal protective equipment when they use a pilot ladder. In addition, the placement of emergency kit on pilot boats and first-aid training are required in order to deal with emergency situation promptly.

• Journal of Communications and Networks
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• v.16 no.4
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• pp.447-457
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• 2014

In this paper, we investigate the frequency domain channel estimation for multiple-input multiple-output (MIMO) single-carrier frequency-division multiple-access (SC-FDMA) systems. In MIMO SC-FDMA, code-division multiplexed (CDM) pilots such as cyclic-shifted Zadoff-Chu sequences have been adopted for channel estimation. However, most frequency domain channel estimation schemes were developed based on frequency-division multiplexing of pilots. We first develop a channel estimation error model by using CDM pilots, and then analyze the mean-square error (MSE) of various minimum MSE (MMSE) frequency domain channel estimation techniques. We show that the cascaded one-dimensional robust MMSE (C1D-RMMSE) technique is complexity-efficient, but it suffers from performance degradation due to the channel correlation mismatch when compared to the two-dimensional MMSE (2D-MMSE) technique. To improve the performance of C1D-RMMSE, we design a robust iterative channel estimation (RITCE) with a frequency replacement (FR) algorithm. After deriving the MSE of iterative channel estimation, we optimize the FR algorithm in terms of the MSE. Then, a low-complexity adaptation method is proposed for practical MIMO SC-FDMA systems, wherein FR is performed according to the reliability of the data estimates. Simulation results show that the proposed RITCE technique effectively improves the performance of C1D-RMMSE, thus providing a better performance-complexity tradeoff than 2D-MMSE.

• Fashion & Textile Research Journal
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• v.22 no.6
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• pp.844-852
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• 2020

This study is to understand the preferences of pilots, flight engineers and crew who work in the same aircraft but are exposed to different working environments and perform different mission operations in order to develop an ergonomic flight jacket. Based on a preliminary investigation, a survey of 107 pilots and 36 flight engineers and crew was conducted. The results are as follows; Pilots can control the temperature inside the cockpit, so they are less exposed to the cold when working, while flight engineers and crew are exposed to the cold more because they have many external tasks. The reason for the problem of the current flight jacket was a difference in ranking between two groups, but the highest ranking was poor dimensional suitability due to the habit of wearing layers of clothing. As a result of preferred design, there were significant differences between groups in the item of overall style. Pilots preferred a bomber jacket style(P:68.2%, E&C:44.4%), on the other hand, flight engineers and crew preferred a field jacket style(P:26.2%, E&C:55.6%)(p<.01). They preferred a stand collar(P:71.0%, E&C:86.1%), a fastener slider for a front fastening(P:62.6%, E&C:61.1%), fastener tape cuffs(P:54.2%, E&C:47.2%), a jacket with a softshell(P:86.9%, E&C:83.3%), fleece as softshell material(P:88.8%, E&C:69.4%), and fastener sliders as a attaching method(P:69.2%, E&C:61.1%). A hem fastening will be selected differently according to the overall style of outshell. Additionally, they preferred more than 5ea pockets(P:51.4%, E&C:44.4%), fastener sliders as pocket's fastenings(P:48.6%, E&C:61.1%), armpit ventilations(P:62.9%, E&C:58.5%). The results of above will be considered to design an ergonomic flight jacket.