• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1800-1803
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• 1997

This paper presents new feedback actuators to achieve an accurate position control of a flexible gnatry robot arm. the translational motion in the plane is generated by two d.c.motors and controlled by emplying elecor-rheological(ER) clutch acutators. The generated motion can be continuously controlled by controlling the intensity of lectric field imposed to the ER fluid domain which tunes the transmitted torque of the ER clutch. n the other hand, during control action of the translational motion a flexible arm attached to the moving mass produces undesirable oscillatins due to its inherent flexibility. The oscillations are actively suppressed by applying feedback voltages to piezoceramic acutators bonded on the surface of the flexible arm. The control electric fields to be applied to the ER clutch and the control voltage for the piezoceramic actuator are determined via the loop shaping esign procedures(LSDP) in the H.inf. control technique. Comsequently, an accuate positiion control at the end-point of the flexible am is achieved during planar motion.

• Bulletin of the Korean Mathematical Society
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• v.36 no.4
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• pp.671-682
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• 1999

Using a base-point free version of the infinite symmetric product we define a fibrewise infinite symmetric product for any fibration $E\;\longrightarrow\;B$. The construction works for any commutative ring R with unit and is denoted by $R_f(E)\;l\ongrightarrow\;B$. For any pointed space B let $G_I(B)\;\longrightarrow\;B$ be the i-th Ganea fibration. Defining $M_R-cat(B):= inf{i\midR_f(G_i(B))\longrihghtarrow\;B$ admits a section} we obtain an approximation to the Lusternik-Schnirelmann category of B which satisfies .g.a product formula. In particular, if B is a 1-connected rational space of finite rational type, then $M_Q$-cat(B) coincides with the well-known (purely algebraically defined) M-category of B which in fact is equal to cat (B) by a result of K.Hess. All the constructions more generally apply to the Ganea category of maps.

• Communications of the Korean Mathematical Society
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• v.10 no.2
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• pp.439-442
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• 1995

Let ${X_n : n = 1,2,\cdots}$ be a sequence of pairwise independent identically distributed random vectors taking values in a separable Hilbert space H such that $E \Vert X_1 \Vert = \infty$. Let $S_n = X_1 + X_2 + \cdots + X_n$ and for any real $\alpha$ with $0 < \alpha < 1$ define a sequence ${\gamma_n(\alpha)}$ as $\gamma_n(\alpha) = inf {r : P(\Vert S_n \Vert \leq r) \geq \alpha}$. Then $$ lim_{n \to \infty} sup \Vert S_n \Vert/\gamma_n(\alpha) = \infty $$ holds. This is a generalization of Vvedenskaya[2].

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.569-572
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• 1996

Explicit state-space formulate for an H$_{.inf}$ based two-degrees-of-freedom robust controller are derived in discrete-time. The controller provides robust stability against coprime factor uncertainty, and a degree of robust performance in the sense of making the closed-loop system match a prespecified reference model. It is shown that the controller consists of a plant observer, the chosen reference model, and a generalized state feedback law associated with the plant and model states. The controller structure is shown to be relatively simple and thus may reduce the computational load on the digital control processor.

• Journal of Ocean Engineering and Technology
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• v.13 no.2 s.32
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• pp.176-185
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• 1999

Currently, large size shipyards have performed the generating of piece and the nesting using shipbuilding-oriented CAD program, which requires high skilled operator and costs a lot. So, medium and small size shipyards have pursued other way to obtain the generating and the nesting due to an economic and a technical problems. Therefore, this research is to develop a program for the generating of pieces with parametric macro method and a STRIP program for the nesting of pieces by PC.

• Journal of Advanced Information Technology and Convergence
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• v.10 no.2
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• pp.1-13
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• 2020

This paper presents an emergency brushless synchronous generator having rotating exciter status monitoring and protection functions. For monitoring the rotating exciter status, a wireless rotor status detector and a digital AVR(Automatic Voltage Regulator), which has a wireless communication capability, are proposed. The proposed rotor status detector detects temperatures of exciter armature and main field windings and input voltage and current of the main field. Therefore, it is possible to protect the generator from the over-temperature of windings and detect the exciter bridge diode fault. Furthermore, the proposed digital AVR has rotor status monitoring and protection function, and remote generator tuning, wireless group parallel operation function. So the operator can efficiently operate the generator using a smartphone from a remote area.

• Bulletin of the Korean Mathematical Society
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• v.38 no.4
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• pp.657-662
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• 2001

It is proved that if for each n, $1\leqp_n\leq2 \;and \;the(p_n, p’_n)$ Clarkson inequality holds in each Banach space X$_{n}$ then the (t, t’) Clarkson inequality holds in ($\sum^\infty_{n=1}\; X_n)_r, \;the \ell^r-sum \;of\; X_n’s,\; where\; 1\leqr<\infty,\; t=min{p, r, r’} \;and \;p = \;inf{p_n}.$ The (p, p’) Clarkson inequality is preserved by quotient maps and a new proof of a Takahashi-Kato theorem stating that the (p, p’) Clarkson inequality holds in a Banach space X if and only if it holds in its dual space $X_*$ is given.n.

• Journal of Evidence-Based Herbal Medicine
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• v.1 no.1
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• pp.7-11
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• 2008

The purpose of this study was to investigate the anti-inflammatory effects of extract from Hwang lyun tang (HLT) on the THP-1 cell and HMC-1 cell. To evaluate of anti-inflammatory of HLT, we examined cytokines production in lipopolysacchride (LPS)-induced THP-1 cell and A23187, PMA-induced HMC-1 cell. Extract of HLT inhibit LPS-induced interleukin (IL)-8 production in human monocyte THP-1 cells. Extract of HLT inhibit A23187, PMA-induced IL-8, tumor necrosis factor-$\alpha$ (INF-$\alpha$) production in HMC-1 cells. HLT down-regulated LPS-induced IL-8 production and A23187, PMA-induced IL-8, TNF-$\alpha$ production, which may be provide a clinical basis for anti-inflammatory properities of HLT.

• Journal of Evidence-Based Herbal Medicine
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• v.1 no.1
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• pp.1-5
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• 2008

Objectives : The purpose of this study was to investigate the anti-inflammatory effects of extract from Jak-Yak Tang (JYT) on the THP-1 cell and HMC-1 cell. Method : To evaluate of anti-inflammatory of JYT, we examined cytokines production in lipopolysacchride (LPS)-induced THP-1 cell and A23187, PMA-induced HMC-1 cell. Result : Extract of JYT inhibit LPS-induced interleukin (IL)-8 production in human monocyte THP-1 cells. Extract of JYT inhibit A23187, PMA-induced IL-8, tumor necrosis factor-$\alpha$ (INF-$\alpha$) production in HMC-1 cells. Conclusion : NT down-regulated LPS-induced IL-8 production and A23187, PMA-induced IL-8, TNF-$\alpha$ production, which may be provide a clinical basis for anti-inflammatory properities of JYT.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1700-1703
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• 1997

The flexibility of the manipulator inevitably inducess the vibration at the end effector. For the increase in speed and accuracy at the end tip, in this work, position and vibration control of a flexible manipuator with a separate voice coil type actrator for vibration suppression, is studied. The flexible manipulator with a tip mass is modeled an Euler-Bernoulli beam. An H.inf. controller is designed in order to make the controlled system robust against unmodeled higher-order mode vibration of the manipulator, output sensor noise, and etc. Simulations and experiments show that the modeling of the system is valid and that robust vibration control of the flexible manipulator is efficiently achieved.