• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.2
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• pp.329-339
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• 2002

In ship operation the consequency of roll motions can seriously degrade the performance of mechanical and personnel effectiveness. So many studies for the roll stabilization control system design have been performed and very good results have been achieved. In many studies, the stabilizing fins are used. Recently rudders, which have been extensively modified, have been used to exclusively to stabilize the roll. This paper examines the two-degree-of-freedom servosystem design technique to synthesize the yaw control system which achieves the course keeping object of the ship and the H$_{\infty}$ control approach to suppress the roll motion, respectively.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.11
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• pp.1142-1146
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• 2014

This paper addresses on a $H_{\infty}$ sampled-data stabilization of a Takagi-Sugeno (T-S) fuzzy system. The sampled-data stabilization problem is formulated as a discrete-time stabilization one via a direct discrete-time design approach. It is shown that the sampled-data fuzzy control system is asymptotically stable whenever its exactly discretized model is asymptotically stable. Based on an exact discrete-time model, sufficient design conditions are derived in the format of linear matrix inequalities (LMIs). An example is provided to illustrate the effectiveness of the proposed methodology.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.2
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• pp.157-178
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• 2001

In this paper, the nonlinear control of high precision pointing stabilization system using feedback-linearization design methodology based on system parameter identification is discussed. Modern nonlinear servomechanism theory is adapted to cope with the hard nonlinearities inherent in the turret system. The mathematical models of electrical turret driving system to develop a high performance control algorithm are derived, and the parameter estimation algorithm identifying the unknown system parameters such as vicious and coulomb frictions, stiffness and inertia is developed. Through computer simulation and experiments, it is shown that pointing and tracking accuracy and stabilization against the wideband stochastic disturbance induced by vehicle running on the bump course are improved. Therefore, it is considered the proposed nonlinear control technique is effective in counteracting the nonlinearities and disturbances.

• Journal of the Korean Society for Precision Engineering
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• v.9 no.3
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• pp.102-109
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• 1992

The heavy vibrations of vehicles on the severe off-road environment degenerate the stabilization proformance of the gunner primary sight. To improve the stabilization performance, the dynamic equations of the gunner primary sight were derived, and the stabilization systems were designed using VSC methods. The performances were compared with the Lead/Lag scheme. In the nonlinear simulation including real disturb ances and couloumb friction, it is shown that the VSC methods exhibit more effective stabilization.

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1649-1654
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• 2003

We have investigated substituent effect on the stabilization energies, and nucleus-independent chemical shifts of pentafulvalenes and on the electronic structures of the corresponding polypentafulvalenes to design environmentally stable semiconductive or conductive polymers. Geometrical optimizations of the molecules were carried out at the density functional level of theory with B3LYP hybrid functional and 6-311+G(d) basis set. Stabilization energies were estimated using isodesmic and homodesmotic reactions. As a criterion of aromaticity nucleus-independent chemical shifts of the molecules were computed using GIAO approach. For the polymers the geometrical parameters were optimized through AM1 band calculations and the electronic structures were obtained through modified extended Huckel band calculations. It is found that strong electronwithdrawing substituents increase isodesmic and homodesmotic stabilization energies of pentafulvalene, though it does not increase the aromaticity. Nitro-substituted pentafulvalene is estimated to have stabilization energy as much as azulene. However, substitution either with electron-donating groups or with electronwithdrawing groups does not significantly affect the electronic structures of polypentafulvalene and poly (vinylenedioxypentafulvalene).

• Journal of Korean Physical Therapy Science
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• v.27 no.2
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• pp.88-95
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• 2020

Background: In the present study to investigate the immediate effects of standing position of the trunk stabilization exercise on Guillain-Barre syndrome patient's balance and gait abilities were examined. Design: Case report and conducted as a single-blind. Methods: Standing position of trunk stabilization exercise was conducted for five Guillain-Barre syndrome patient's who met the selection criteria were recruited. The subjects were conducted conservative exercise and trunk stabilization exercise. Conservative exercise was implemented for thirty min, five times for 8 weeks, and trunk stabilization exercise was implemented for 15 min. The participants' balance was measured via force plate (COP), functional reach test (FRT), timed up and go test (TUG), gait was measured using the 10 m walk test, and 6 minute walk test. Results: After training, the change values of the balance and gait ability in the subjects were significantly greater than pre-test. participants showed significant improvements in COP, FRT, TUG, 10 m walk test and 6 minute walk test pre and post the training (p<0.05). Conclusions: standing position of the trunk stabilization exercise was effective on Guillain-Barre syndrome patient's balance (COP, FRT, TUG) and gait (10 m walk test and 6 minute walk test) abilities were examined.

• Journal of Korean Physical Therapy Science
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• v.29 no.4
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• pp.96-111
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• 2022

Background: This study aims to evaluate the effect of core stabilization exercise on the dynamic balance and horizontal rotation of the trunk in young adult men. Through this study, it is expected that various core stabilization exercises will prevent and treat musculoskeletal disease. Design: Randomized Controlled Trial. Methods: The study subjects were recruited from young adult men in their 20s and 30s living in Seoul, and after the randomized controlled trial, it was divided into an experimental group training core stabilization exercise(n=15) and a control group(n=15). The evaluation methods of this study were modified Star Excursion Balance Test(mSEBT), Functional Reach Test(FRT), and Trunk Rotation Test(TRT). The experimental group performed three sets of crunches and deadbug exercises twice a week for eight weeks, and the control group did not perform any exercises similar to core stabilization exercise during the experimental period. Results: The result of the experiment, the experimental group showed significant improvement in mSEBT(p<.05), FRT(p<.05) and TRT(p<.05). Conclusion: In conclusion, core stabilization exercises improved dynamic balance and horizontal rotation of the trunk. As a result of this study, core stabilization exercise can prevent and treat musculoskeletal diseases even in healthy people.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1744-1746
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• 2004

This paper focuses on the problem of asymptotic stabilization for time-delay systems. To this end, a memoryless state feedback controller is proposed. Then, based on the Lyapunov method, a delay-dependent stabilization criterion is devised by taking the relationship between the terms in the Leibniz-Newton formula into account. Certain free weighting matrices are used to express this relationship and linear matrix inequalities (LMIs)-based algorithm to design the controller stabilizing the system.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.36-41
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• 1998

This paper presents a stabilization algorithm for a class of fuzzy systems with singleton consequect. To this aim, we introduce two canonical forms of an unforced fuzzy system and a stability theorem. A design example is shown to verify the stabilization algorithm.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.523-525
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• 2005

This paper deals with a linear matrix inequality (LMI) approach to the design of a static output feedback controller that simultaneously stabilizes a finite collection of linear time-invariant plants. Simultaneous stabilization by static ouput feedback is represented in terms of LMIs with a rank condition. An iterative penalty method is proposed to solve the rank-constrained LMI problem. Numerical experiments show the effectiveness of the proposed algorithm.