• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.27 no.2
• /
• pp.47-53
• /
• 2019

The development of the aviation industry and the changes in the military operation mission environment are demanding more long - distance operation (long - time flight), and such a flying environment is a risk factor for fatigue - related accidents. For the aviation related organizations such as ICAO and FAA, fatigue risk management system (FRMS) are applied along with flight time restriction regulations to prevent fatigue related accidents. The most important process in FRMS is fatigue risk management. Fatigue risk management systematically manages fatigue through scientific fatigue risk data collection and fatigue risk assessment. The purpose of this study is to applicate the assessment of scientific fatigue risk management to pilots of airplanes engaged in long flight. We reviewed the current state of risk management and FRMS through previous research. We also developed fatigue risk management indicators and examined the validity of internationally recognized fatigue risk data collection methods and fatigue risk assessment tools. There are 134 mission (flight) data used for development. In order to verify the indicators, the fatigue risk score between the items was assigned through pair-wise comparison. In addition, the verify test results were normalized.

• Journal of Aerospace System Engineering
• /
• v.15 no.1
• /
• pp.40-46
• /
• 2021

In this study, an aerodynamic configuration design and study on performance enhancement of a tilt-rotor UAV were conducted for improving mission capabilities compared to multi-copter type UAV, MC-1/2/3 developed for disaster and policing operation. To improve performance, a new TR5X configuration was developed by modifying the fuselage and tail shape of TR60 UAV and additionally attaching an extended wing to the nacelle. Aerodynamic performances of TR60 and TR5X were compared through computational fluid dynamics (CFD) analysis. In addition, flight performance analysis of full aircraft was conducted. Results showed that main performance requirements of TR5X were satisfied.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.25 no.2
• /
• pp.177-186
• /
• 2022

A network QoS model for the joint integrated C4I structure was proposed for the integration of network infrastructure and network operations(NetOps) for NCOE. Detailed QoS requirements process of the joint integrated C4I systems are needs in the Multi-Domain Operation Environment(MDOE). A process is proposed for identifying QoS requirements and establishing in the MDOE using JMT(Joint Mission Thread) reference architecture and solution architecture. Mission analysis identify JCOAs(Joint Critical Operational Activities) and related activities based on JMT & System architecture's OVs, and Information analysis identify QoS attributes using System architecture's SVs. Identifying QoS attributes will be registered at PPS Registry by pre-regulated process, and will be set-up by NetOps. MDOE QoS requirement Process will support efficiently MUM-T and smart defense platform users under the future uncertain battlefield circumstances.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.50 no.8
• /
• pp.591-597
• /
• 2022

In this paper, we analyzed linkbudget with comparing actual received level of telemetry system at Palau Tracking Station. Because Palau Tracking Station participated in the launch mission for the first time and lack of verification tests for antenna tracking and signal reception performance, we analyzed the linkbudget more accurately by predicting transmit antenna polarization gain according to the trajectory and attitude of launch vehicle. The analysis results were used to analyze signal reception range, antenna operation angle and LHCP/RHCP received level. The actual received level of the antenna was similar to the linkbudget result as a result of the launch mission operation.

• Journal of Astronomy and Space Sciences
• /
• v.27 no.3
• /
• pp.253-262
• /
• 2010

The electrical power system (EPS) of Korean satellites in low-earth-orbit is designed to achieve energy balance based on a one-orbit mission scenario. This means that the battery has to be fully charged at the end of a one-orbit mission. To provide the maximum solar array (SA) power generation, the peak power tracking (PPT) method has been developed for a spacecraft power system. The PPT is operated by a software algorithm, which tracks the peak power of the SA and ensures the battery is fully charged in one orbit. The EPS should be designed to avoid the stress of electronics in order to handle the main bus power from the SA power. This paper summarizes the results of energy balance to achieve optimal power sizing and the actual trend analysis of EPS performance in orbit. It describes the results of required power for the satellite operation in the worst power conditions at the end-of-life, the methods and input data used in the energy balance, and the case study of energy balance analyses for the normal operation in orbit. Both 10:35 AM and 10:50 AM crossing times are considered, so the power performance in each case is analyzed with the satellite roll maneuver according to the payload operation concept. In addition, the data transmission to the Korea Ground Station during eclipse is investigated at the local-time-ascending-node of 11:00 AM to assess the greatest battery depth-of-discharge in normal operation.

• The Journal of Korea Robotics Society
• /
• v.10 no.1
• /
• pp.24-32
• /
• 2015

This paper introduces a graphical user interface design that is aimed to apply to the surveillance and security robot, which is the pilot program for the army unmanned light combat vehicle. It is essential to consider the activities of robot users under the changing security environment in order to design the efficient graphical user interface between user and robot to accomplish the designated mission. The proposed design approach firstly identifies the user activities to accomplish the mission in the standardized scenarios of military surveillance and security operation and then develops the hierarchy of the interface elements that are required to execute the tasks in the surveillance and security scenarios. The developed graphical user interface includes input control component, navigation component, information display component, and accordion and verified by the potential users from the various skilled levels with the military background. The assessment said that the newly developed user interface includes all the critical elements to execute the mission and is simpler and more intuitive compared to the legacy interface design that was more focused on the technical and functional information and informative to the system developing engineers rather than field users.

• The Bulletin of The Korean Astronomical Society
• /
• v.39 no.2
• /
• pp.110.1-110.1
• /
• 2014

The optics of Space telescope is one of the major parts of space mission used for imaging observation of astronomical targets and the Earth. These kinds of space mission have a bulky and complex opto-mechanics with a long optical tube, but there are attempts have been made to observe a target with a small satellite in many ways. In this paper, we describe an optical design of a reflecting telescope for use in a CubeSat mission. For this design, we adopt the off-axis segmented method of astronomical observation techniques based on the Ritchey-Chr$\acute{e}$tien type telescope. The primary mirror shape is a rectangle with dimensions of $8cm{\times}8cm$, and a secondary mirror has dimensions of $2.4cm{\times}4.1cm$. The focal ratio is 3 which can obtain a $0.3{\times}0.2$ degree diagonal angle in a $1280{\times}800$ CMOS color image sensor with a pixel size of $3{\mu}m{\times}3{\mu}m$. This optical design can capture a ${\sim}4km{\times}{\sim}2.3km$ area of the earth's surface at 700 km altitude operation. Based on this conceptual design, we will keep trying to study more for astronomical observation with Attitude control system.

• Journal of Computing Science and Engineering
• /
• v.2 no.4
• /
• pp.375-393
• /
• 2008

The dynamic cast operation allows flexibility in the design and use of data management facilities in object-oriented programs. Dynamic cast has an important role in the implementation of the Data Management Services (DMS) of the Mission Data System Project (MDS), the Jet Propulsion Laboratory's experimental work for providing a state-based and goal-oriented unified architecture for testing and development of mission software. DMS is responsible for the storage and transport of control and scientific data in a remote autonomous spacecraft. Like similar operators in other languages, the C++ dynamic cast operator does not provide the timing guarantees needed for hard real-time embedded systems. In a recent study, Gibbs and Stroustrup (G&S) devised a dynamic cast implementation strategy that guarantees fast constant-time performance. This paper presents the definition and application of a cosimulation framework to formally verify and evaluate the G&S fast dynamic casting scheme and its applicability in the Mission Data System DMS application. We describe the systematic process of model-based simulation and analysis that has led to performance improvement of the G&S algorithm's heuristics by about a factor of 2. In this work we introduce and apply a library for extracting semantic information from C++ source code that helps us deliver a practical and verifiable implementation of the fast dynamic casting algorithm.

• Journal of the Optical Society of Korea
• /
• v.17 no.6
• /
• pp.533-537
• /
• 2013

Space telescope optics is one of the major parts of any space mission used to observe astronomical targets or the Earth. This kind of space mission typically involves bulky and complex opto-mechanics with a long optical tube, but attempts have been made to observe a target with a small satellite. In this paper, we describe the optical design of a reflecting telescope for use in a CubeSat mission. For this design we adopt the off-axis segmented method for astronomical observation techniques based on a Ritchey-Chr$\acute{e}$tien type telescope. The primary mirror shape is a rectangle with dimensions of $8cm{\times}8cm$, and the secondary mirror has dimensions of $2.4cm{\times}4.1cm$. The focal ratio is 3 which can yield a 0.383 degree diagonal angle in a $1280{\times}800$ CMOS color image sensor with a pixel size of $3{\mu}m{\times}3{\mu}m$. This optical design can capture a ${\sim}4km{\times}{\sim}2.3km$ area of the earth's surface at 700 km altitude operation.

• The Bulletin of The Korean Astronomical Society
• /
• v.46 no.2
• /
• pp.57.3-57.3
• /
• 2021

99942 Apophis is an Sq-type Potentially Hazardous Asteroid (PHA) with an estimated diameter of 370 m. It will approach the Earth down to 31,000 km from the surface during the encounter on April 13, 2029 UT, which is closer than geostationary satellites. This once-in-a-20,000 year opportunity would further expand our knowledge on the physical and dynamical processes which are expected to occur due to the gravitational tidal forces when an asteroid encounter with a planet. It will also provide an opportunity to promote great knowledge of the science of planetary defense. The science goal of the Apophis mission is to global-map the asteroid before and after the Earth's approach. In this talk, we will present scientific objectives, and briefly introduce instruments and operation scenarios of the mission.