• Journal of Mechanical Science and Technology
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• v.19 no.5
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• pp.1138-1147
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• 2005

This paper aims at demonstrating the feasibility of active control of beams with a multiobjective state-feedback control technique. The multiobjective state-feedback controller is de­signed on a linear matrix inequality (LMI) approach for the multiobjective synthesis. The design objectives are to achieve a mix of Hoo performance and H2 performance satisfying constraints on the closed-loop pole locations in the face of model uncertainties. The controller is also designed to reject the effects of the noise and external of disturbances. For the theoretical analysis, the governing equation of motion is derived by Hamilton's principle to describe the dynamics of a smart structural system. Numerical examples are presented to demonstrate the effectiveness of the integrated robust controller in damping out the multiple vibration modes of the piezo/beam system.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.209-214
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• 2010

Metastasis is the primary cause of from breast cancer mortality. Cell migration and invasion play important roles in neoplastic metastasis. Matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix (ECM), plays an important role in cancer cell invasion. NF-${\kappa}B$ is transcription factor important in the regulation of MMP-9, as the promoter of MMP-9 gene contains binding sites for NF-${\kappa}B$. Brazilin, an active component of sappan wood (Caesalpinia sappan), decreases TPA-induced MMP-9 expression and invasion in MCF-7 cells. Also, brazilin suppressed NF-${\kappa}B$ activation in TPA-treated MCF-7 cells. Taken together, we demonstrated that the inhibition of TPA-induced MMP-9 expression and cell invasion by brazilin is mediated by the suppression of the NF-${\kappa}B$ pathway in MCF-7 cells. This result suggest brazilin provide a potential therapeutic app roach for the treatment of breast cancer.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.09a
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• pp.442-449
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• 2003

This paper presents a robust hybrid control system for seismic response control of a cable-stayed bridge. Because multiple control devices are operating, a hybrid control system could alleviate some of restirctions and limitations that exist when each system is acting alone. A LQG algorithm with on-off control scheme, H$_2$ and H$_{\infty}$ control algorithms with various frequency weighting filters are used to improve the controller robustness of the active control part in the hybrid control system. The numerital simulation results show that control performances of robust hybrid control systems are similar to those of the hybrid control system with LQG algorithm. Furthermore, it is verified that robust hybrid control systems are more robust than the hybrid control system with LQG algorithm and there are no signs of instabilities in the $\pm$5％ stiffness matrix perturbed system. Therefore, the proposed hybrid control system have a good robustness for stiffness matrix perturbation without loss of control effectiveness.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.3
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• pp.172-179
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• 2003

Linear matrix Inequality based $H_\infty$ robust controller is designed to control the motion of a 4-axis unbalanced rigid asymmetric rotor supported and controlled by two active magnetic bearings in this paper. To this end, the equations of motion of the system are derived via Hamilton's variational principle and transformed to a state-space form for the standard $H_\infty$ control problem. LMI-based controller, which does not require additional assumptions beyond the usual stabilizability and detectability assumptions, is designed based upon the pole place weighting function and loopshaping technique. The obtained results are compared with those reported in the available literature and the efficiency of the proposed LMI-based $H_\infty$ control is revealed.

• Journal of the Korean Society of Food Culture
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• v.34 no.4
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• pp.463-473
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• 2019

The aim of this study is to identify the value structure of active seniors for noodles. Noodles are the secondly most preferred and familiar food in Korea, followed by rice. And noodles also have a variety of tastes/flavors and even a variety of ceremonial characteristics. The necessity of offering proper food to seniors has recently increasing because Korea becoming an aged society. This study conducted 1:1 in-depth interviews with 30 active senior participants using the soft laddering technique, which is based on the means-end chain theory. The Implication Matrix and HVM were derived from performing content analysis. The active seniors mainly consider the 'taste', expecting to obtain the 'satisfying taste', and pursuing the 'family affair', 'pleasure', and 'self-satisfaction'. The results of this study indicated that the taste is the most important attribute and the active seniors consider their family as well as the pleasure and satisfaction of their own. Male seniors mainly pursue the 'pleasure' and 'self-satisfaction' by satisfying their taste through considering 'taste' and 'familiarity'. But female seniors mainly pursue the 'family affair' by 'satisfying taste' through considering 'taste'. These results can be used as a basic data for developing noodle products for the elderly. This study will also contribute to the development of special care food and product concepts for the silver generation.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.8
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• pp.649-660
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• 2021

Through analytical method based on S-76 model, the level of rotor hub vibration reduction was analyzed according to higher harmonic actuating by individual blade control. The higher harmonic actuating method for individual blades was divided into a method of generating an additional actuating force from the pitch-link in the rotating part and generating actuating force through the active trailing edge flap control of the blade. In the 100kts forward flight conditions, the hub load analysis was performed by changing the phase angle of 15 degree for the 2P/3P/4P/5P harmonic actuation for individual blades. Through the harmonic actuation results, the sensitivity of the rotor system according to the actuating conditions was analyzed, and the T-matrix representing the characteristics of the rotor system was derived based on this analysis result. And through this T-matrix, optimal higher harmonic actuating condition was derived to minimize hub vibration level for flight condition. In addition, the effect on the performance of the rotor system and the pitch-link load under minimum hub vibration condition, as well as the noise influence through the noise analysis were confirmed.

• Korean Journal of Medicinal Crop Science
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• v.27 no.4
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• pp.247-258
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• 2019

Background: Astragali radix (A) and Lithospermi radix (L) have long been used as traditional medicines due to their known anti-inflammatory effects. This study aimed at evaluating, their optimal mixing ratio and their functional compounds by investigating the inhibitory effects of mixed extracts of A and L and their active compounds on matrix metalloproteinases (MMPs). Methods and Results: A and L extracts were obtained by extraction at $80^{\circ}C$ using 50% and 70% fermented alcohol, respectively, and then mixed at a ratio of 5 : 5, 6 : 4, 7 : 3 and 8 : 2 (w/w). The activities of MMP-1, MMP-3, and MMP-13 were evaluated in interleukin-1beta ($IL-1{\beta}$)-induced SW1353 cells. The extract mixtures showed synergistic inhibitory effects on MMP-3 and MMP-13, higher than the effects of the individual A and L extracts. The 7 : 3 mixture (ALM16) showed the most effective MMPs inhibitory activity, while among the active ingredients, calycosin-7-O-${\beta}$-D-glucoside and lithospermic acid exhibited excellent MMPs inhibitory activity. Additionally, an HPLC method was established for simultaneous quantification of the effective components of the extract mixtures, and validated by measuring the linearity, precision and accuracy of the limit of detection (LOD) and limit of quantification (LOQ). Conclusions: ALM16 showed the most effective MMPs inhibitory activity. Calycosin-O-${\beta}$-D-glucoside, calycosin and lithospermic acid were identified as useful candidates, as they were the major functional compounds in the MMP inhibitory activity. Summarily, ALM16 might be a highly effective in osteoarthritis management, owing to its because it exhibits a protective effect on cartilage via excellent inhibition of MMPs.

• Korean Journal of Clinical Pharmacy
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• v.1 no.1
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• pp.23-30
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• 1991

The sustained-release beads containing terbutaline sulfate (TBS) were prepared by rotogranulation method. The drug was dusted on the non-pareil seeds in a CF-granulator. The sustained-release beads were obtained by coating the active beads with ethylcellulose or $Eudragits^{(R)}$, using in any case the same granulator employed for active beads preparation. The release characteristics of sustained-release beads were examined in vitro by rotating basket method applied to $Bricanyl^{(R)}$ durules which is a sustained-release TBS matrix tablet. The release of terbutaline from the beads in vitro was first-order, and the release rate was dependent on both the coat weight ratio and membrane hydrophilicity. Both surfaces of the beads before and after dissolution were smooth. The drug release pattern from the beads could be thought the diffusion through the polymer membrane. The release rate and the surface of the beads stored for 3 years at room temperature were the same with those of the initial beads.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.3 s.108
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• pp.298-306
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• 2006

In our previous paper, we developed a robust saturation controller for the linear time-invariant (LTI) system involving both actuator's saturation and structured real parameter uncertainties. This controller can only guarantee the closed-loop robust stability of the system in the presence of actuator's saturation. But we cannot analytically make any comment on control performance of this controller. In this paper, we suggest a method to use linear matrix inequality (LMI) optimization problem which can analytically explain control performance of this robust saturation controller only in nominal system. The availability of design method using LMI optimization problem for this robust saturation controller is verified through a numerical example for the building with an active mass damper (AMD) system.

• Journal of Electrical Engineering and Technology
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• v.8 no.3
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• pp.572-580
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• 2013

Power metering and monitoring system is a basic element of Smart Grid technology. This paper proposes a new Non-Intrusive Load Monitoring (NILM) method for a residential buildings sector using the measured total active power consumption. Home electrical appliances are classified by ON/OFF state models, Multi-state models, and Composite models according to their operational characteristics observed by experiments. In order to disaggregate the operation and the power consumption of each model, an algorithm which includes a switching function, a truth table matrix, and a matching process is presented. Typical profiles of each appliances and disaggregation results are shown and classified. To improve the accuracy, a Time Lagging (TL) algorithm and a Permanent-On model (PO) algorithm are additionally proposed. The method is validated as comparing the simulation results to the experimental ones with high accuracy.