• Journal of Platform Technology
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• v.11 no.3
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• pp.24-31
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• 2023

Recently, interest in UAM (Urban Air Mobility, UAM), which can take off and land vertically in the operation of urban air transportation systems, has been increasing. Therefore, various start-up companies are developing related technologies as eco-friendly future transportation with advanced technology. However, studies on ways to increase safety in the operation of UAM are still insignificant. In particular, efforts are more urgent to improve the safety of risks generated in the process of attempting to land in the city center by UAM equipped with autonomous driving. Accordingly, this study proposes a plan to safely land by avoiding dangerous region that interfere when autonomous UAM attempts to land in the city center. To this end, first, the latitude and longitude coordinate values of dangerous objects observed by the sense of the UAM are calculated. Based on this, we proposed to convert the coordinates of the distorted planar image from the 3D image to latitude and longitude and then use the calculated latitude and longitude to compare the pre-learned feature descriptor with the HOG (Histogram of Oriented Gradients, HOG) feature descriptor to extract the dangerous Region. Although the dangerous region could not be completely extracted, generally satisfactory results were obtained. Accordingly, the proposed research method reduces the enormous cost of selecting a take-off and landing site for UAM equipped with autonomous driving technology and contribute to basic measures to reduce risk increase safety when attempting to land in complex environments such as urban areas.

• Strategy21
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• s.34
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• pp.149-177
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• 2014

Today distant oceans around the world are regarded as a major 'global commons' for international trade and transportation. Korea is not an exception, because Korea hugely depends on sea lines of communication (SLOC) for supplying vital commodities such as food and energy resource. As a result, assuring a free and safe use of distant ocean beyond territory is also an important agenda for Korea's maritime security. However there are a number of challenges for Korea to enjoy a free and safe use of distant ocean; dangers of regional maritime conflict in East Asia, naval arms race of China and Japan, and concerns on possible decline of U.S naval presence and power projection capabilities. These factors provide a reasonable basis for Republic of Korea Navy (ROKN) to pursue capabilities for major naval operations at distant ocean in a long-term perspective toward the year 2030. The introduction of aircraft carrier and nuclear-powered submarine is a key requirement for achieving this goal. ROKN needs to acquire a 'multi-role strategic landing platform' type of light aircraft carrier, which takes a role to escort naval task force by providing air superiority at distant ocean. Additionally nuclear-powered submarine will offer ROKN a formidable power to carry out offensive missions effectively at distant ocean.

• Journal of Advanced Navigation Technology
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• v.15 no.6
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• pp.994-999
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• 2011

This paper explains how existing electrical ADU(Antenna Distribution Unit) has been improved into a mechanical ADU. Generally the mechanical ADU has stabilized Glide Path which provides a RF signal to the aircraft for safe landing and it has solved the issue of phase shift and power distribution ratio change which can be occurred during long-term use. Besides it has been certified by Flight check and operating several airports in oversea as well as in korea.

• Journal of Aerospace System Engineering
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• v.3 no.3
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• pp.1-6
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• 2009

The first Type Certificate project for small airplane is in progress in the Republic of Korea. Therefore, it is necessary to prepare the circumstances that the airplane developed and certificated by this country will exported to foreign countries and operated in the world. One of the main items to be prepared is the systems related with continuing airworthiness of aircraft during the operation. From this point of view, the systems and corresponding capabilities to maintain the aircraft to continue the flight and safe landing will be the immediate work. This study is to review the continuing airworthiness system established by foreign countries such as USA FAA and European EASA and to propose how we will setup our continuing airworthiness system for the airplane developed and certificated by the Republic of Korea.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.6
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• pp.473-480
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• 2013

Researches for various lunar landing technologies are in progress for the lunar exploration program planned for early 2020s in Korea. This paper shows the integrated simulation for safe lunar landing guidance/control system in powered descent phase. Generally, the lunar lander uses on/off(bang-bang) controller to control the RCS jet thrusters instead of proportional controller. In this paper, the on/off controller using phase-plane switching function, and thruster selection algorithm to control sixteen thrusters are applied. Also additional guidance commands are calculated by a proposed fuzzy logic guidance algorithm. The simulation results show that lunar lander can follow a reference trajectory which is generated by optimization method, then land on the surface safely.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.2
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• pp.89-94
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• 2023

Recently, domestic small airport development plans are being promoted centering on islands, and among them, Baengnyeong Island Airport is located very close to North Korea due to its geographical characteristics. In particular, since it is located in the P-518, which is prohibited airspace, it is essential to configure the arrival/departure flight procedure route similarly to the current ship in terms of securing flight safety. Therefore, in this study, a plan for airport location and facility scale was proposed by focusing on the runway operated for the purpose of aircraft operation through consultations with the Ministry of National Defense. It was proposed to meet the standards of the Airport Facility Act as an airport dedicated to domestic flights for airside facilities such as runway length and direction, target aircraft, landing pad, apron, runway and taxiway width appropriate for the topographical characteristics of Baengnyeong Island. As a result, the flight procedure is generally established as a two-way visual flight, but the 10-way arrival/departure procedure was planned to be changed to an instrument (non-precision) according to the specificity of the region. In addition, a flight procedure was established and presented for safe and systematic operation by reflecting the changes in airport facility size (landing pad, runway end safety area, etc.) following the change in instrument flight procedure in the visual flight procedure.

• The Journal of Industrial Distribution & Business
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• v.8 no.6
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• pp.61-73
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• 2017

Purpose - Aviation control, navigation, and aircraft control in the air transportation area are very specialized. Each part is in progress for safety, efficiency, automation, and further. On the other hand co-work among each part including knowledge sharing has been inattentive for many reasons. The purpose of this research is to show how practicians and professionals in the air transportation area perceive the issue of knowledge sharing and to recall the necessity of knowledge sharing in the area. And we try to find ways to activate the knowledge sharing in the area. Research design, data, methodology - For the research, we inquired into whether practicians and professionals think knowledge sharing can effect safe aviation positively or not and what steps are necessary to activate knowledge sharing in the area. We adopted survey method using questionnaires for current practicians and interview for specialists. The survey and interview results were analyzed using regression analysis and AHP method. The interview for specialists and analyzing the results using AHP was to investigate what are the precedence factors to activate the knowledge sharing. Results - First, practicians perceive that knowledge sharing will affect aviation safe positively. Second objective knowledges such as, tower air traffic control procedure of aviation control area, flight principle and structure of aircraft control area, instrument landing system of navigation area, for knowledge sharing of each area were identified. Also the precedence factors such as, knowledge absorbability of personal factor, personal expectation of result of expectation factor, leadership of management of Structure factor, method of knowledge spread of application factor for knowledge sharing were found. Conclusions - Knowledge sharing for practicians and professionals in the aviation area is very important especially from the perspective of safety. However, for various many reasons including the environment of each special area that focusing on their own area, knowledge sharing has not been emphasized. We found that practicians in the area feel that knowledge sharing is necessary and helpful. For it, each practician's active participation is the most important and many ways such as chatting room to share knowledge are to be developed. And the organization culture should be changed to encourage knowledge sharing.

• Journal of Positioning, Navigation, and Timing
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• v.4 no.1
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• pp.1-7
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• 2015

In the case of an unmanned aerial vehicle (UAV) equipped with a GNSS sensor, a boundary line where the vehicle can actually exist can be calculated using a navigation error model, and safe navigation (e.g., precise landing and collision prevention) can be supported based on this boundary line. Therefore, for the safe operation of UAV, a model for the position error of UAV needs to be established in advance. In this study, the multipath error of a GNSS sensor installed at UAV was modeled through a flight test, and this was analyzed and compared with the error model of an existing manned aircraft. The flight test was conducted based on a scenario in which UAV performs hovering at an altitude of 40 m, and it was found that the multipath error value was well bound by the error model of an existing manned aircraft. This result indicates that the error model of an existing manned aircraft can be used in operation environments similar to the scenario for the flight test. Also, in this study, a scenario for the operation of multiple UAVs was considered, and the correlation between the multipath errors of the UAVs was analyzed. The result of the analysis showed that the correlation between the multipath errors of the UAVs was not large, indicating that the multipath errors of the UAVs cannot be canceled out.

• The Journal of the Convergence on Culture Technology
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• v.6 no.1
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• pp.1-6
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• 2020

This study is about the safe arm posture in case of emergency escape using the vertical dive rescue sack at the fire site. The experimental results are as follows. First, the arms extended upward contact with the endothelium and narrowing part of the rescue sack minimized the scratches did not occur. Second, the bent position with both arms open was subject to light abrasions of on the elbows due to friction between the elbows and the scapula and the endothelium. Third, in the posture where both arms were gathered in the chest, the body passed through the narrowing part and friction between the bag's narrowing part, All subjects had light abrasions on their elbows. Fourth, because the arms are lowered, the legs are extended to the width of the shoulders when descending, so that the back of the hand has friction with the narrowing part of the bag and the endothelial skin. Finally, posture with both arms below the front increased the volume of the front of the body, resulting in a slight back injury. As a future research task, it is necessary to study the proper posture of legs and the posture of landing on the ground.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.513-520
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• 2004

A steady-state/transient performance simulation model was newly developed for the propulsion system of the CRW (Canard Rotor Wing) type UAV (Unmanned Aerial Vehicle) during flight mode transition. The CRW type UAV has a new concept RPV (Remotely Piloted Vehicle) which can fly at two flight modes such as the take-off/landing and low speed forward flight mode using the rotary wing driven by engine bypass exhaust gas and the high speed forward flight mode using the stopped wing and main engine thrust. The propulsion system of the CRW type UAV consists of the main engine system and the duct system. The flight vehicle may generally select a proper type and specific engine with acceptable thrust level to meet the flight mission in the propulsion system design phase. In this study, a turbojet engine with one spool was selected by decision of the vehicle system designer, and the duct system is composed of main duct, rotor duct, master valve, rotor tip-jet nozzles, and variable area main nozzle. In order to establish the safe flight mode transition region of the propulsion system, steady-state and transient performance simulation should be needed. Using this simulation model, the optimal fuel flow schedules were obtained to keep the proper surge margin and the turbine inlet temperature limitation through steady-state and transient performance estimation. Furthermore, these analysis results will be used to the control optimization of the propulsion system, later. In the transient performance model, ICV (Inter-Component Volume) model was used. The performance analysis using the developed models was performed at various flight conditions and fuel flow schedules, and these results could set the safe flight mode transition region to satisfy the turbine inlet temperature overshoot limitation as well as the compressor surge margin. Because the engine performance simulation results without the duct system were well agreed with the engine manufacturer's data and the analysis results using a commercial program, it was confirmed that the validity of the proposed performance model was verified. However, the propulsion system performance model including the duct system will be compared with experimental measuring data, later.