• Journal of Life Science
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• v.27 no.12
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• pp.1437-1444
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• 2017

Sargassum macrocarpum is a widely distributed marine brown algae found in the North Pacific. The objective of this study was to evaluate the anti-inflammatory activity of an ethanol extract of S. macrocarpum (EESM). First, we investigated the anti-inflammatory activities of EESM in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. EESM treatment suppressed nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) production and inhibited the expressions of the inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the mRNA and protein levels. In addition, the expression of pro-inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) and interleukin-1 beta ($IL-1{\beta}$), was decreased in a dose dependent manner. Investigation of the signaling pathways of nuclear factor kappa B ($NF-{\kappa}B$), phosphoinositide-3-kinase (PI3K)/Akt, and mitogen-activated protein kinases (MAPKs) revealed suppression of $NF-{\kappa}B$ translocation from the cytosol to nucleus by EESM treatment. The phosphorylation of the Akt and ERK proteins was also inhibited by EESM treatment. EESM treatment also stimulated the expression of the heme oxygenase-1 (HO-1) enzyme and its upstream transcription factor, nuclear factor-E2-related factor 2 (Nrf2). These results suggest that EESM has anti-inflammatory activity and could have potential uses in the field of nutraceuticals.

• Proceedings of the KIEE Conference
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• 2008.04a
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• pp.163-165
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• 2008

In this paper we compare performance of exponential effective SINR mapping (EESM) with traditional actual value interface (AVI) approach for various modulation and coding schemes (MCS) in terms of coded bit error rate (BER) or block error rate (BLER) using different transmission schemes. This paper provides explanation and comparison of the two algorithms for single input single output (SISO), and single input multi-output (SIMO, 1X2) in OFDM systems. We calibrate the value of beta ($\beta$) in EESM using large number of channel realizations, here $\beta$ is a calibration constant. This paper also presents importance of beta value in EESM and how it improves the performance of OFDM wireless systems. We propose different modulation and coding schemes. Here we consider Standford university interim (SUI) channel models. Furthermore this paper also shows the detail observation of the two algorithms. Finally the conclusion review given for short summary.

• Journal of Power Electronics
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• v.12 no.4
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• pp.615-622
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• 2012

The switching frequency of the power electronic devices used in large synchronous motor drives is usually kept low (less than 1 kHz) to reduce the switching losses and to improve the converter power capability. However, this results in a couple of problems, e.g. an increase in the harmonic components of the stator current, and an undesired cross-coupling between the magnetization current component ($i_m$) and the torque component ($i_t$). In this paper, a novel complex matrix model of electrically excited synchronous motors (EESM) was established with a new control scheme for coping with the low switching frequency issues. First, a hybrid observer was proposed to identify the instantaneous fundamental component of the stator current, which results in an obvious reduction of both the total harmonic distortion (THD) and the low order harmonics. Then, a novel complex current controller was designed to realize the decoupling between $i_m$ and $i_t$. Simulation and experimental results verify the effectiveness of this novel control system for EESM drives.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.1
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• pp.47-57
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• 1991

A new control algorithm so called equal excursion sliding mode (EESM) control method is proposed to control the position of DC servo motor. This method introduces the concept of phase velocity vector that Filippov presented, and simplifies the problem of control gain selection in a conventional VSC strategy. And, by making state trajectories have equal excursions on both sides of switching hyperplane we minimized the probability of sliding mode's being collapsed, and approximated to the ideal sliding moed. Also, we proved the validity of this method by comparing the application results of this method to DC servo motor with those of conventional VSC strategy.