• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.718-721
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• 2007

The ionic-polymer-metal-composite actuators have the best merit for bio-mimetic locomotion because of their large bending performance. Especially, they have the advantage for mimicking a fish-like motion because IPMCs are useful to be actuated in water. So we have developed IPMC actuators with multiple electrodes for realization of biomimetic motion. This actuator is fabricated by combining electroless plating and electroplating techniques capable of patterning precisely and controlling a thickness of Pt electrode layer. The FRF analysis was conducted by a mechanical shaker and direct electrical excitation which is based on sweep sine wave function. From this result, the proper young‘s modulus of Platinum was investigated and applied on expecting the vibration characteristics of patterned IPMC actuator. The calculated maximum displacement of the patterned IPMC was 2.32mm under an applied 4mN/mm. The natural frequency was increased however displacement was decreased in according to increase a thickness of Pt.

• Molecular & Cellular Toxicology
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• v.4 no.1
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• pp.72-77
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• 2008

The present study was undertaken to determine whether pioglitazone treatment influences on the agonist-induced vascular smooth muscle contraction and, if so, to investigate the related mechanism. The measurement of isometric contractions using a computerized data acquisition system was combined with molecular experiments. Pioglitazone decreased Rho-kinase activating agonist-induced contraction but not phorbol ester-induced contraction suggesting the least involvement of $Ca^{2+}$-independent thin filament regulation of contractility. Furthermore, pioglitazone decreased thromboxane $A_2$ mimeticinduced phosphorylation of MYPT1 at Thr855, the newly-highlighted site, instead of Thr696. In conclusion, this study provides the evidence and possible related mechanism concerning the vasorelaxing effect of pioglitazone as an antihypertensive on the agonist-induced contraction in rat aortic rings regardless of endothelial function.

• Radiation Oncology Journal
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• v.33 no.2
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• pp.66-74
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• 2015

Trace elements play crucial role in the maintenance of genome stability in the cells. Many endogenous defense enzymes are containing trace elements such as superoxide dismutase and metalloproteins. These enzymes are contributing in the detoxification of reactive oxidative species (ROS) induced by ionizing radiation in the cells. Zinc, copper, manganese, and selenium are main trace elements that have protective roles against radiation-induced DNA damages. Trace elements in the free salt forms have protective effect against cell toxicity induced by oxidative stress, metal-complex are more active in the attenuation of ROS particularly through superoxide dismutase mimetic activity. Manganese-complexes in protection of normal cell against radiation without any protective effect on cancer cells are more interesting compounds in this topic. The aim of this paper to review the role of trace elements in protection cells against genotoxicity and side effects induced by ionizing radiation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.119-123
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• 2006

The ionic-polymer-metal-composite actuators have the best merit for bio-mimetic locomotion because of their large bending performance. Especially, they have the advantage for mimicking a fish-like motion because IPMCs are useful to be actuated in water. So we have developed IPMC actuators with multiple electrodes for realization of biomimetic motion. Generally, the IPMC actuator has been fabricated in electroless plating technique, while it needs very long fabrication time and shows poor repeatability in the actuation performance owing to the variables in chemical fabrication process. Therefore, the novel fabrication methods were investigated by combining electroless plating and electroplating techniques capable of patterning precisely. On the whole, two different methods were compared and analyzed with similar thickness level of Platinum electrodes. Present results show that mixing chemical reduction and electroplating can be a promising candidate for electrode patterning.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.10 no.4
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• pp.308-313
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• 2010

This paper presents a performance index-based evaluation for a better quadruped robotic walking configuration. For this purpose, we propose a balance-based performance index that enables to evaluate the walk configuration of quadruped robots in terms of balance. In order to show the effectiveness the proposed performance index, we consider some types of walking configurations for a quadruped robotic walking and analyze the trend of the proposed performance index in those quadrupedal walking. Through the simulation study, it is shown that an effective walk configuration for a quadrupedal walking can be planned by adopting the proposed performance index.

• Journal of Biomedical Engineering Research
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• v.38 no.5
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• pp.242-247
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• 2017

This study presents a bio-chemical energy harvesting system which can generate electric power from bioorganic substance contained in vermicompost. It produced electricity by inoculating microbial fuel cell(MFC) with earthworm-composted food waste. The generated electricity was converted into usable voltage level for mobile electronics through power conditioning circuits. The implemented prototype showed $200{\mu}W$ of maximum output electric power, which successfully supplied a beacon device which continuously transmitted data to nearby smartphone without a battery. The proposed system can help develop portable or bio-mimetic energy supply for sustainable use with further improvement.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.508-517
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• 1998

We investigated the effects of godulbaegi extracts on the physiochemical properties of biological membranes as membrane stability and fluidity employing the phospholipid liposomal membrances as a biomembrane-mimetic system. The addition of the godulbaegi extracts to the phospholipid exterted great effects stagbilized the barrier function of the liposomal membranes in proportion to the concentration of the additive and significantly increased the membranes fluidity. The values of the fluorescence polarization of 1,6-diphenyl 1,3,5-hexatriene (DPH) decreased gradually as the temperature increased, and decreased abruptly near the phase transition temperature (Tm) of the liposome from gel to liquid crystalline state as usual. These results suggest that the activities of the godulbaegi extracts to enhance the stability and fluidity of the liposomal membranes have implication in their biological activities.

• Proceedings of the KIEE Conference
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• 2001.11c
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• pp.107-110
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• 2001

Recently, there are lots of concerning on robot agent system working for itself with the trends of the research of bio-mimetic system and intelligent robot. In this paper, a virtual 3D interface system is proposed based on Internet for remote controlling and monitoring of mobile robot. The proposed system is constructed as manager-agent model. A worker can order the robot agent move to a new position by clicking the destination on virtual space of 3D graphic interface in manager. Then the robot agent move to the position automatically with avoiding collision by using range finding and autonomous control algorithm. The proposed robot agent system lets us control the mobile robot remotely located more conveniently.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.2 s.191
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• pp.64-72
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• 2007

Many human-body motions such as walking, running, jumping, etc. require a significant amount of power. To achieve a high power-to-weight ratio of the humanoid robot system, this paper proposes a new design of the bio-mimetic leg mechanism resembling musculoskeletal system of the human body. The hip joints of the system considered here are powered by 5 human-like bi-and mono-articular muscles, and the joints of knee and ankle are redundantly actuated by both bi-articular muscles and joint actuators. The kinematics for the leg mechanism is derived and a kinematic index to measure force transmission ratio is introduced. It is demonstrated through simulation that incorporation of redundant muscles into the leg mechanism enhances the power of the mechanism approximately 2 times of the minimum actuation.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.24 no.3
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• pp.154-161
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• 2011

Objective : Needle embedding therapy is a newly induced therapy which uses specialized tools. The purpose of this study is to report the nasolabial folds correction effect of needle embedding therapy on 5 cases. Method : Five women with no disease were received needle embedding therapy four to six times over one to two months. The photos of each patient were taken before and after the treatment. Also, Glogau photoaging classification were assessed before and after the treatment. Result and conclusion : Needle embedding therapy may be an effective and safe treatment for the correction of nasolabial folds.