• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.571-574
• /
• 2005

This paper gives some sufficient conditions for a given polyhedral set which is represented as a set of linear inequalities to be positive D-invariant for uncertain linear discrete-time systems in the case such that the systems matrices depend linearly on uncertain parameters whose ranges are given intervals. Further, the results will be applied to uncertain linear continuous systems in the sense of the above by using Euler approximation.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.92.3-92
• /
• 2001

This paper is concerned with robust attitude control of large space structures with collocated sensors and actuators. Since the transfer function matrices of such systems are symmetric, it seems suitable to employ symmetric controllers. This paper shows that it is true if no constraint is imposed on the orders of the controllers, but it is not true if the orders of the controllers are specified to be lower than that of the system to be controlled.

• Proceedings of the KIEE Conference
• /
• 1993.07b
• /
• pp.1122-1124
• /
• 1993

In this study, piezoceramics/polymer composites with 3-3 connectivity were made by BURPS(Burnout Plastic Sphere) technique with PZT ceramics and PVA sphere. And physical and dielectric properties dependent on the PVA wt.% were investigated. The density of porous piezoceramic and pieaoceramic/polymer composites were decreased almost linearly with increasing the PVA wt.%.

• Proceedings of the PSK Conference
• /
• 2000.04a
• /
• pp.216.1-216.1
• /
• 2000

• 한국생물공학회:학술대회논문집
• /
• 2003.04a
• /
• pp.289-292
• /
• 2003

Effects of immobilization on the production of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) by Nicotiana tabacum cells were investigated using alginate and polyurethane foam as immobilization matrices. Encapsulation of the cells in alginate decreased protein production by 50% compared with that of suspension culture. Maximum hGM-CSF concentration was obtained by the cells immobilizaed in polyurethane foam. High hGM-CSF production could be possible when polyurethane foam was used because of high specific production and easy immobilization for cell recycling process with high cell density.

• Proceedings of the IEEK Conference
• /
• 2004.08c
• /
• pp.473-476
• /
• 2004

Low-Density Parity-Check (LDPC) codes are recently emerged due to its excellent performance to use. However, the parity check matrices (H) of the previous works are not adequate for hardware implementation of encoders or decoders. This paper proposes a hybrid parity check matrix for partially parallel decoder structures, which is efficient in hardware implementation of both decoders and encoders. Using proposed methods, the encoding design can become practical while keeping the hardware complexity of partially parallel decoder structures.

• 한국생물공학회:학술대회논문집
• /
• 2001.11a
• /
• pp.671-674
• /
• 2001

Cyclodextrin glucanotransferase(CGTase) derived from recombinant Bacillus subtilis was partial purified and concentrated by ultrafiltration. The prepared CGTase were immobilized on various matrices by ionic interaction or covalent bond. CGTase covalently bound on CNBr-activated sepharose 4B were identified to be the highest immobilization activity among various immobilization methods. The optimum conditions for CGTase immobilization were determined; $30^{\circ}C$, 6Orpm, using O.2g CNBr-activated sepharose 4B in pH 6.0 phosphate buffer and 9hr immobilization.

• Journal of Electrical Engineering and Technology
• /
• v.8 no.6
• /
• pp.1551-1558
• /
• 2013

$H_2$ design of decoupled control systems is treated in the generalized plant model. The existence condition of a decoupling controller is stated and a parameterized form of all achievable decoupled closed loop transfer matrices is presented by using the directional interpolation approaches under the assumption of simple transmission zeros. The class of all decoupling controllers that yield finite cost function is obtained as a parameterized form and an illustrative example to find the optimal controller is provided.

• Bulletin of the Korean Mathematical Society
• /
• v.46 no.6
• /
• pp.1141-1149
• /
• 2009

In this article, we study surfaces of revolution without parabolic points in a Euclidean 3-space whose Gauss map G satisfies the condition ${\Delta}^hG\;=\;AG,A\;{\in}\;Mat(3,{\mathbb{R}}),\;where\;{\Delta}^h$ denotes the Laplace operator of the second fundamental form h of the surface and Mat(3,$\mathbb{R}$) the set of 3${\times}$3-real matrices, and also obtain the complete classification theorem for those. In particular, we have a characterization of an ordinary sphere in terms of it.

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.34S no.1
• /
• pp.43-53
• /
• 1997

A robust stability condition for linear systems with time delay in all variables and parameter uncertainties in all system matrices is derived. Robust performance condition that accounts for robust model-matching of closed loop system and disturbance rejection is also derived. Using the robust performance condition, robust $H^{\infty}$ controller and .mu.(sgructured singular value) controller with two-degree-of-freedom(2DOF) are designed. The controller structure is considered for $H^{\infty}$ controller, while uncertainity structure is considered for .mu. controller. Using the proposed method, $H^{\infty}$ and .mu. controllers for underwater vehicle with time delay and parameter variations are designed. Simulations of a design example with hydrodynamic parameter variations and disturbance are presented to demonstrate the achievement of good robust performance.ce.