• Aerospace Engineering and Technology
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• v.13 no.2
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• pp.18-28
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• 2014

We assume that two control moment gyros are installed for space qualification in a satellite with four reaction wheels, and study the high agile maneuver method. Using high torque control moment gyros, we reduce the satellite's attitude error. After that, we activate reaction wheels to control remaining attitude error. This proposed method can avoid singularity problem of control moment gyros, and do not require gimbals' angle to calculate torque command. Through numerical simulations, we show that our method's agile performance is similar to previous method and reduce the reaction wheels' required momentum.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.9
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• pp.53-59
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• 2006

Need for agile satellite increases for performing various mission due to increase of satellite image applications and users. In high resolution satellite TDI (time delay and integration) method is adopted in order to improve SNR. But image quality can be degraded by satellite maneuver. In this paper requirements for remote sensing in high resolution satellite with agility are extracted and an approach to operate the agile satellite to perform the missions are proposed. The proposed approach in this paper will be applicable to system level design and analysis.

• The Korean Journal of Emergency Medical Services
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• v.10 no.3
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• pp.61-70
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• 2006

Purpose: The purpose of this study is to develop a realistic illustration using watercolors on a complete airway obstruction maneuver that is at an appropriate level for elementary school students from the first grade through the third. The illustration is a series of cuts divided into specific frames designed to illustrate the method to be followed in an action or a practical skill that would otherwise be too difficult to explain in written form. Methods: The fundamental theory of the Jeong In-Sung's instruction learning program based on the WEB to construct an appropriate site of instruction learning was used after modification. In this study analysis, design, and production stages were realized. Results: 1. In Stage 1, impressions of the illustration, in sketch form, were received. In Stage 2, results of impressions from a modified illustration were received. After an appropriate level of understanding and accuracy in the practical steps for emergency maneuvers were achieved the illustrations entering Stage 3 and color was added to the sketches. 2. In Stage 3, the illustration was completed by adding color to the contents for the practical steps in the complete airway obstruction maneuver. 3. For composition evaluation, a result of 100% appropriateness was obtained for both items of harmony between illustration and subject being studied and sufficiency in quantity of illustrations. Also high results for appropriateness in items such as clarity, creating interest, illustration size, and tone preference as related to content were achieved and thus completed the production stages. Conclusion: The Complete Airway Obstruction Maneuver Illustration developed specifically for the characteristics and cognitive level of elementary school students grade 1 through grade 3 was appropriate for teaching and learning. There is a need for future research on developed illustrations aimed at elementary school students grade 1 through 3 on the complete airway obstruction maneuver. There is also a need for continued effort in developing certified evaluating tools that can judge the suitability of illustrations and developing illustrations related to emergency maneuvers for various subjects and appropriate for learner level.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.63.5-63
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• 2002

In this paper, we are concerned with a maneuver detection algorithm which uses the 'lost' measurements down-sampled for computation load saving when a target is in quiescent motion. In general applications of estimation, measurements are available at a relatively high rate, while the estimation processing equipment can only operate at a lower sampling rate. Furthermore, when a target is in nearly quiescent motion, the update of the tracking filter need not to be implemented with maxim urn process power of the filter since the states of the target vary relatively slowly. This does not give serious degradation on the estimation performance. We consider the maneuver detection problem at the case...

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.5
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• pp.355-361
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• 2020

Among these satellites, low - orbit small satellites with military characteristics require multi - target observation, and demand for high-resolution photographs and images is increasing. Fast maneuverability is the most important factor for high-resolution images and multi - target observations. However, in the case of a small satellites, it is possible to perform the attitude maneuver if it has high speed, but the residual vibration occurs when the attitude maneuver is completed and the next attitude maneuver is completed. In this study, to verify the vibration characteristics of the plate generated after attitude maneuver, an experimental fixture for simulating the attitude maneuver was fabricated and tested. In addition, Eddy Current Damper (ECD) using Eddy Current Brake system (ECB) is proposed as a passive damping method using permanent magnet to reduce vibration. A mathematical model was established to apply ECD and it was experimentally implemented according to the magnetic flux density and the air gap of the permanent magnet. One plate of four solar panels (plate) was specified, the residual vibration reduction performance after the test was verified experimentally.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.6
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• pp.548-556
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• 2015

The highly maneuverable fighter aircraft such as F-22, F-16 and F-15have the high maneuverability to maximize the combat performance, whereas the high maneuver characteristics might degrade the pilot's mission efficiency due to fatigue's increase by exposing him to the high gravity and, in the worst case, the pilot could face GLOC (Gravity-induced Loss Of Consciousness). The advanced aerospace company has applied the various technologies to improve the pilot's tolerance to the gravity acceleration, in order to prevent the pilot from entering the situation of the loss of consciousness. Especially, the Anti-G Suit(AGS) equipment to protect the pilot against the high gravity in flight could improve the mission success rate by decreasing the pilot's fatigue in the combat maneuver as well as prevent the pilot from facing GLOC. In this paper, a control algorithm is developed and verified to provide an optimal air pressure to AGS according to the gravity increase during the high performance maneuver. This result is expected, as the key technology, to contribute to the KF-X(Korean Fighter eXperimental), project in the near future.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.3
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• pp.230-236
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• 2018

This paper deals with the improvement of pressurized quality for high maneuver aircraft. Anti-G Valve is a pressure regulating valve for inflating anti-G suits and providing a sense line signal for a g-compensated oxygen regulator. The new anti-g valve system is satisfied with military specification MIL-V-87255 and allowed the pilots to tolerate high-G exposures without any vibrations. The flight test was performed by two T/FA-50 pilots and other tests used the centrifuge made by anti-g developer. A comparison of the new anti-g valve with period one, it have better response and low chattering phenomenon.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.148.4-148
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• 2001

This paper shows an autopilot design example with simulation results for a medium range surface-to-air missile used to intercept fast maneuver targets. The missile is assumed to use both aerodynamic fins and side thrusters to achieve fast time response. The steady-state maneuver capability of the missile is assumed to be enough at high altitude to engage usual maneuvering targets. Side thruster is used to get an extremely rapid acceleration response at high altitude where the missile´s aerodynamic control effectiveness is weak. The strategy of control design is firstly to employ side thrusters to achieve a rapid response and then to hand-over the control to the aerodynamic fins to maintain the desired acceleration command in the steady state ...

• Animal cells and systems
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• v.9 no.1
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• pp.41-46
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• 2005

This study was conducted to reveal tree species preference and inter-specific difference of foraging behavior among four canopy-dwelling birds at forest dominated by Quercus mongolica, Acer pseudosieboldian and Carpinus cordata at 1,000 meters above sea level during breeding season of birds from 1995 to 1997 in Mt. Jumbongsan. Breeding birds were about 25 species and dominant birds were Erithacus cyane, Parus ater and Parus palustris. A relatively high number of bush-nesters can be a characteristic of breeding bird community at study area. Three gleaners (Tits, P. varius, P. palustris and P. ater) selectively preferred the trees irrespective of dominant tree species, whereas bark foragers (Nuthatch, Sitta europaea) utilized the dominant trees. The four birds showed significant inter-specific difference in use of foraging location, but the three tits did not show significant inter-specific difference in use of foraging maneuver and trees. Closely related tits may coexist with each other by inter-specific different use of foraging location determined by foliage structure and leaf arrangement.

• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.1
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• pp.100-113
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• 2017

Snap rolling during hard turning and instability during emergency rising are important features of submarine operation. Hydrodynamics modeling using a high incidence flow angle is required to predict these phenomena. In the present study, a quasi-steady dynamics model of a submarine suitable for high-incidence-angle maneuvering applications is developed. To determine the hydrodynamic coefficients of the model, static tests, dynamic tests, and control surface tests were conducted in a towing tank and wind tunnel. The towing tank test is conducted utilizing a Reynolds number of $3.12{\times}10^6$, and the wind tunnel test is performed utilizing a Reynolds number of $5.11{\times}10^6$. In addition, least squares, golden section search, and surface fitting using polynomial models were used to analyze the experimental results. The obtained coefficients are presented in tabular form and can be used for various purposes such as hard turning simulation, emergency rising simulation, and controller design.