• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.754-756
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• 1996

In this paper, polymer housing arrester has very good characteristics in design versatility as well as excellent resistance to moist ingress and pollution performance. For the presented of the characteristics evaluation and technology of disk spring and knuckle structure of FRP to filament winding seems to protect the arrester elements from moisture absorption. The achievement in the research and technology will contribute to the showed very good characteristic in adhesion of terminal cap and FRP cylinder for outdoor arresters and domestic products of high voltage power distribution arrester.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.399-402
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• 1993

In this paper, an inverse kinematics of redundant manipulators is proposed. Optimality-constraint based inverse kinematic algorithms have some problems because those algorithms are based on necessary conditions for optimality. Among the problems, switching from a maximum value to a minimum value may occur and make an inverse kinematic solution unstable while performing a given task. An inverse kinematic solution for protecting from the switchings is suggested. By sufficient conditions for optimality, the configuration space is defined as a set of regions, potentially good configuration region and potentially bad configuration region. Inverse kinematics solution within potentially good configuration region can provide joint trajectories without both singularities and switchings. Through a simulation of tracing a circle, we show the effectiveness of this inverse kinematics.

• Industrial Engineering and Management Systems
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• v.2 no.1
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• pp.1-8
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• 2003

Among many dimensional or dimensionless amplitude parameters, kurtosis and ID Factor are said to be sensitive good parameters for machine diagnosis. In this paper, a simplified calculation method for both parameters is introduced when impact vibration arise in the observed data. Compared with the past papers' results, this new method shows a good result which fit well. This calculation method is simple enough to be executed even on a pocketsize calculator and is very practical at the factory of maintenance field. This can be installed in microcomputer chips and utilized as a tool for early stage detection of the failure.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.6
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• pp.2005-2013
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• 1996

Particle paths and flow fields in a prototype differential mobility analyzer (DMA) were numerically analyzed solving Navier-Stokes equation, electric field equation and particle motion considering viscous drag force, Coulomb force and polarization force. Analytically predicted particle diameters for the prototype DMA are in good agreement with the measured particle diameters within $\pm$1%. And the analytically predicted particle diameters are also in good agreement with numerical results for the prototype DMA.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2005.09a
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• pp.124-128
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• 2005

To produce a highly sensitive uncooled microbolometer, the development of a high-performance thermometric material is essential. In this work, amorphous vanadium-tungsten oxide was developed as a thermometric material at a low temperature of $300^{\circ}C$, and the microbolometer, coupled with the material, was designed and fabricated using surface micromachining technology. The vanadium-tungsten oxide showed good properties for application to the microbolometer, Such as a high temperature coefficient of resistance of over -4.0 $\%$/K and good compatibility with the surface micromachining and integrated circuit fabrication process due to its low fabrication temperature. As a result, the uncooled microbolometer could be fabricated with high detectivity over $1.0\;{\times}\;10^9\;cmHz^{1/2}/W$ at a bias current of $7.5\;{\mu}A$ and a chopper frequency of 10-20 Hz

• International Journal of Advanced Culture Technology
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• v.9 no.3
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• pp.367-372
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• 2021

The purpose of this study is to suggest that the movement expression activity of intellectually disabled people is effective in the learning process of LMA motion recognition based on Kinect sensor. We performed an ICT motion recognition games for intellectually disabled based on movement learning of LMA. The characteristics of the movement through Laban's LMA include the change of time in which movement occurs through the human body that recognizes space and the tension or relaxation of emotion expression. The design and implementation of the motion recognition model will be described, and the possibility of using the proposed motion recognition model is verified through a simple experiment. As a result of the experiment, 24 movement expression activities conducted through 10 learning sessions of 5 participants showed a concordance rate of 53.4% or more of the total average. Learning motion games that appear in response to changes in motion had a good effect on positive learning emotions. As a result of study, learning motion games that appear in response to changes in motion had a good effect on positive learning emotions

• Journal of Applied Biological Chemistry
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• v.64 no.1
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• pp.63-67
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• 2021

Isovitexin, a marker compound with various pharmacological activities, in Lespedeza cuneata, was analyzed using high performance liquid chromatography coupled with UV (HPLC/UV). There are no previous reports on using L. cuneata as the source material for the quantification of isovitexin. In this study, we developed an optimized method using HPLC-UV analysis, which was validated using various parameters. Our method demonstrated high specificity, and good separation of the chromatographic peak was achieved. Parameters such as linearity (r2≥0.9997), precision, and accuracy indicated that our proposed analytical method had good reliability and sensitivity. These results demonstrate the utility and convenience of our method for rapidly quantifying isovitexin in L. cuneata extracts.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.227-227
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• 2006

It was attempted to synthesize polyimides from PPMDA and 3FPPMDA with mDAPPO/pPDA in order to afford CTE of 17ppm and adhesion property of 80g/mm, besides high Tg (>$300^{\circ}C$), good thermal stability (>$500^{\circ}C$), low water absorption and good solubility. The polyimides were prepared via a conventional two-step process; preparation of poly(amic-acid), followed by solution imidization by refluxing in NMP with o-DCB and the molar ratio of mDAPPO/pPDA was varied. The polyimides were characterized by FT-IR, NMR, DSC and TGA. In addition, intrinsic viscosity, solubility and coefficient of thermal expansion (CTE) were also measured.

• Journal of the Korean Vacuum Society
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• v.4 no.S2
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• pp.90-94
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• 1995

Defects introduced by Si, Ge preamorphization and their effects on the dopant diffusion and electrical characteristics. Good crystalline quality are obtained after the annealing of Ge ion double implanted samples. The defect clusters under the a/c interface are expected to extend up to the deep in the Si ion implanted samples. The dislocation loops near the junction absorb the interstitial Si atoms resolving from the defect cluster and result in the prevention of enhanced boron diffusion near the tail region of boron profile and show good reverse current charactristics.

• Journal of the Korean Applied Science and Technology
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• v.30 no.3
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• pp.528-539
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• 2013

Biodiesel is one of the most important renewable energy, since it is one of the most important alternative and eco-friendly energy source compared to fossil energy, especially for diesel engineequipped vehicles. It is now coming up for preparation of biodiesel as the alternative that applies the hetrogeneous catalyst, super critical state and various methods used in order to reduce the stages of the processes be converted and separation stages started from oil and fat which are originated from animals and wastes, and those new methods bring eco-friendly as well, though some of those are stand on research step so far. It is necessary that nation provides the tax exemption program for the supplier and strengthen the research system for the farming crops relate to fat and oil. It can improve the development of biodiesel which sustains stability against oxidation and keeps good mobility over the low temperatures in the winter season by new additives and develops new processes to show good harmony with diesel engine.