• The Journal of Korean Physical Therapy
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• v.24 no.1
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• pp.1-6
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• 2012

Purpose: The grip strength is influenced by various factors, such as position of the upper extremity, characteristics of the hand, and general physical condition. In this study, we investigated whether abdominal muscle activity in combination with the abdominal drawing-in maneuver has any effect on the grip strength in healthy young adults. Methods: This study included 31 healthy subjects (16 males, 15 females). We used surface electromyography and pressure bio-feedback unit for this experiment. All Subjects were placed in a cock-lying position with comfort and the grip strength was measured. On the following day, the pressure bio-feedback unit was placed beneath their fifth lumbar vertebra, and the, grip strength was measured again. This time, the measurement was taken while drawing-in their abdomen below the navel gently and gradually, while maintaining a neutral pelvic position. Results: The grip strength was significantly increased when subjects performed the drawing-in maneuver than when they were comfortable (p<0.05). In addition, activations of the rectus abdominal muscles significantly increased (p<0.05). Conclusion: In the current study, we found that abdominal muscle activity, in combination with the abdominal drawing-in maneuver, affected the grip strength, positively. Therefore, we suggest that this result should be considered when evaluating the grip strength.

• Bulletin of the Korean Space Science Society
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• 2004.10b
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• pp.251-253
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• 2004

Automated east/west and north/south station-keeping maneuvers were simulated for the geostationary COMS (Communication, Ocean and Meteorological Satellite) satellite that will be launched around year 2008, The satellite has to be maintained within ${\pm}0.05^{\circ}$ at the nominal longitude of $128.2^{\circ}\;E$. The general perturbation method was used to keep the position of the geostationary satellite. Weekly based east/west and biweekly based north/south station-keeping maneuvers were investigated. The sun pointing perigee control method and two-bum strategy were used for the east/west station-keeping maneuver. Switching the right ascension of the ascending node to descending node was adopted for the north/south station-keeping maneuver. One year station-keeping maneuver was demonstrated and various station-keeping orbital parameters were analyzed.

• Journal of Navigation and Port Research
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• v.36 no.7
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• pp.571-575
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• 2012

Berthing and unberthing maneuver is essential work for marine pilots and securing the safety against risks during the maneuver is more important than anything else. Moreover, the maneuvering environment in ports and harbors has changed rapidly and got worse due to development of a new port, the advent of a new type or large-sized ship, and the rapid increase in harbor traffic. As one of measures taken to cope with such changes in the maneuvering environment and for each pilot to improve his own maneuvering ability, this paper developed laptop-based ship-handling simulator which is readily available anytime and anywhere. This paper is to develop a conning display for ship's maneuvering and electronic chart based display widely used nowadays to represent a model ship's movement. The displays were arranged appropriately considering pilot age, easy handling by mouse, using a maximum screen, proper arrangement of rudder, engine, thruster, tug etc and representation of information. Up to now thirteen (13) model ships were developed based on real-ship, whose mathematical model is Japanese MMG & pilots' low speed maneuver.

• Advances in aircraft and spacecraft science
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• v.9 no.4
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• pp.279-300
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• 2022

This paper analyzes the possibilities of a new method to using TLE data for detecting satellite maneuvers. The method has a number of advantages over other methods that are designed to detect maneuvers. It allows not only to detect maneuvers, but also to get a more complete picture of the maneuver. In particular, the method makes it possible to estimate the moments of the beginning and end of the maneuver, calculate the changes in the orbital elements, evaluate the tangential and binormal components of the impulse, and finally, calculate the impulse of the satellite obtained as a result of the maneuver. To demonstrate in detail the capabilities of the algorithm, the proposed method was applied to one of LEO satellites - TIANHUI-1 satellite. After the efficiency of the method was proved, this method was applied to the China Space Station - TIANHE-1 (CSS), Starlink-1095 and Starlink-2305 satellites. The maneuvers of the CSS and Starlink-1095 satellite during their close encounter on 1 July, 2021, and the CSS and Starlink-2305 satellite during their close encounter on 21 October, 2021 are analyzed in detail. The minimum distances between the CSS and Starlink satellites at the moments of their maximum approaches are estimated. An estimate of the computation time of this algorithm is given, and the possibility of its use for monitoring maneuvers or other anomalous orbital changes of a large number of satellites in near real-time is shown. It is assumed that on the basis of this method, a service for monitoring satellite maneuvers can be created.

• Journal of Astronomy and Space Sciences
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• v.12 no.1
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• pp.102-111
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• 1995

A series of east/west and north/south station-keeping maneuvers were simulated for the KOREAST spacecraft which has to be maintained within $\pm$0.05 at the nominal longitude of $116^{\circ}$E. Weekly an biweekly based station-deeping maneuver plannings were used, and weekend maneuvers were avoided. All of the station-keeping maneuver plannings and executions were performed using KOREASTA Mission Analysis Software on VAX/VMS operating system. Fourteen weeks station-keeping maneuvers were performed and various station-keeping orbital parameters were obtained.

• 전기의세계
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• v.31 no.2
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• pp.119-125
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• 1982

A new approach to the maneuvering target tracking problem is proposed. Its basic concept is to take the maneuver variable from the measurements. Tracking scheme based on the Kalman filter estimates the maneuver varieble from the residual and uses the estimates to update the Kalman filter. The estimation process is independent of target types and a model of the maneuver characteristics. All the filtering algorithms are processed in polor coordinate. Simulation results are presented and compared to that of the extended Kalman filter.

• Journal of Aerospace System Engineering
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• v.4 no.4
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• pp.37-43
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• 2010

Need for agile satellites increases for performing various mission due to increase of satellite image applications and users. This paper performs attitude maneuver analysis by using Satellite Tool Kit(STK) made by AGI. In order to automate the STK analysis process, a MATLAB program is developed to generate STK input data and to process STK output data. Five attitude maneuver modes are analyzed and attitude angle variation and required torques are calculated.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.2
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• pp.101-110
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• 2013

This paper considers the many kinds of attitude control systems including launcher. JVC(Jet vane control), Jet tap, Jetvator and Movable nozzles are used to control the initial attitude of a missile only. Recently side jet thruster and it's applications to control initial turn and to maneuver at high altitude have been increased. How to design and develop the missile for an initial turn and a high maneuver at high altitude using side jet thrust were described in this paper.

• International Journal of Aeronautical and Space Sciences
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• v.13 no.4
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• pp.474-483
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• 2012

In this paper, a collision avoidance maneuver was sought for low Earth orbit (LEO) and geostationary Earth orbit (GEO) satellites maintained in a keeping area. A genetic algorithm was used to obtain both the maneuver start time and the delta-V to reduce the probability of collision with uncontrolled space objects or debris. Numerical simulations demonstrated the feasibility of the proposed algorithm for both LEO satellites and GEO satellites.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.1147-1156
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• 1993

In order to analyze lateral control in the backward maneuver of a tractor -trailer combination , a kinematic vehicle model and a human operator model with time delay were utilized for the operator/vehicle system. The analysis was carried out using the frequency domain approach. The open-loop stability of the vehicle motion was analyzed through the transfer functions. The sensitivity of the stability of the vehicle motion. to a change in the steering angle, was also analyzed. A mathematical model of the closed -loop operator/vehicle system was then formulated. The closed -loop stability of the operator /vehicle system was then analyzed. The effect of the delay time on the system was also analyzed through computer simulation.