• Proceedings of the KSRS Conference
• /
• 2007.10a
• /
• pp.394-396
• /
• 2007

Radio occultation (RO) technique has been used in planetary science since 1960s. When signal goes through atmosphere, it is refracted due to the gradient of atmospheric refractivity. In 1995, the first low earth orbit (LEO) satellite, MicroLab-1, was launched to conduct RO mission. It receives the signal from global positioning system (GPS) satellites. After MicroLab-1, other RO missions, such as CHAMP, SAC-C, and GRACE, are executed in several years later. In 2006, Taiwan launched six LEO satellites for RO mission. The mission name is Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC). Under some abnormal situations, multipath and strong fluctuation in phase and amplitude of the signal appear in moist troposphere. Therefore, open loop (OL) technique has been applied to replace traditional phase lock loop (PLL) technique. In this paper, we will summarize the retrieval processing procedure and discuss the advantages and disadvantages of OL technique.

• Proceedings of the KSRS Conference
• /
• 2007.10a
• /
• pp.493-495
• /
• 2007

Future sub-meter resolution LEO missions require simultaneous dual-polarization downlink and/or multiple channel downlinks in single polarization. Especially, dual-polarization is needed to cope with bandwidth limitation due to high speed data transmission. Current KARI 13m X-Band antenna system needs to be upgraded to cope with such downlink schemes. This paper describes brief discussions on engineering work regarding how to meet the new requirements with minimum impact on current system as well as C&M (Control and Monitoring) software.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.10a
• /
• pp.60-65
• /
• 2014

Shelter system is applying to weapon systems as usage of performing specific mission with arranging several electronic equipments and operators. Recently the electronic equipments is changing from development products to COTS(Commecial on-the-shelf) for demonstrating high performance at low cost. As internal operators of shelter system conduct several missions for specific or long time in this the present situation, One of the most important element considering the best combat power is internal noise level. Therefore, I desire to analyze the features and foresee muliple noise level with test for conforming whether requirements of design is met or not in this research paper.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.10a
• /
• pp.173-174
• /
• 2014

Vibration disturbances generated by reaction wheels may cause serious problems in high precision pointing spacecraft missions. Implementation of vibration isolator is a practical solution to meet the high pointing stability requirement placed on precision payloads. In this paper, development of hybrid vibration isolator that combines passive and active component is described. Vibration isolation performance of the developed isolator is evaluated using reaction wheel disturbance model. Hybrid isolation results obtained using FxLMS algorithm show clear improvement compared to the results obtained using only passive means.

• Asian Journal of Innovation and Policy
• /
• v.2 no.2
• /
• pp.173-193
• /
• 2013

This paper surveys the development of Asian universities and their path towards the American entrepreneurial type. The paper suggests Asian universities used internationalization and entrepreneurial missions to follow older American entrepreneurial universities with success towards world-class university status. Current studies are lacking on covering the significance of internationalization at Asian entrepreneurial universities and offer few typologies on the diverse Asian transformations of the past approximate thirty years. Thus, paper proposes a theoretical framework linking internationalization with innovation and classifies into 3 types, the various Asian entrepreneurial university transformations from an international comparative perspective. It then examines the type using case studies.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.17 no.3
• /
• pp.40-50
• /
• 2009

Avionics system's function for an air transport mission is analysed. The starting point for designing a Avionics system is a clear understanding of the mission requirements and the requirement allocation by the top level aircraft system. Therefore, the analysis begins by making a top-down analysis to the aircraft missions. The baseline mission is divided into segments, and each segment is subjected to a detailed analysis to establish the requirements for the Avionics system. Special attention is given to capture the key aspects of interfaces, and to incorporate them into the design.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.15 no.3
• /
• pp.15-23
• /
• 2007

In this paper, we deducted the missions with respect to Korea utility helicopter (KUH) and consist of the scenarios which describe proper purpose of KUH. And so developed fatigue load spectrum of KUH by applying Helix that is fatigue load spectrum for blade of articulated helicopter rotor system. The developed load spectrum is applied to fatigue analysis of blade by modeled finite element with stress-life method (S-N). And we compared the result of fatigue analysis to prior to Helix for the sake of verifying the load spectrum that we generated.

• International Journal of Aeronautical and Space Sciences
• /
• v.12 no.4
• /
• pp.379-384
• /
• 2011

This paper performs numerical prediction of fuel temperature in the fuel tanks of unmanned air vehicles for both ground static non-operating and in flight transient conditions. The calculation is carried out using a modified Dufort-Frankel scheme. For this calculation, it is assumed that a non-operating vehicle on the ground is subjected to repeating daily cycles of ambient temperature with solar radiation and wind under 1%, with a 20% probability of hot day conditions. The energy conservation equation is used as the governing equation to calculate heat transfer between the fuel tank surface and the ambient environment. Results of the present analysis may be used as the estimated initial values of fuel temperatures in a vehicle's fuel tank for the purpose of analyzing transient fuel temperatures during various flight missions. This research also demonstrates that the fuel temperature of the front tank is higher than that of the rear tank, and that the difference between the two temperatures increases in the later phases of flight due to the consumption of fuel.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.11
• /
• pp.3200-3206
• /
• 2009

This paper describes the problem of existing maintenance system for mail sorting machnies, and presents to-be considerations of maintenance system based on AHP (Analytic Hierarchy Process) analysis with efficiency and economic aspects. There are standard procedure for diagnosis and repair of mail sorting machine as preventive and operational maintenance, roles and missions of maintenance technical support center for upgrade of maintenance skill in this paper. The proposed maintenance system will be adapted for more safety and efficiency maintenance of mail sorting machine.

• Proceeding of EDISON Challenge
• /
• 2017.03a
• /
• pp.511-515
• /
• 2017

Various walking robot platforms have been developed to carry out missions such as explorations, pass of obstacle or inspections of dangerous environments. In this work, a four legs mechanism based on Jansen mechanism is developed, which can trace a certain line. In order to maximize the tracing speed, mechanism design is performed in multiple phases using m.sketch, EdisonDesign and Arduino programs. In design process, control of power path and optimization of the locus of legs(GL/GAC) are found to be most important. A prototype model is constructed and test run to check the validity of the design optimization.