• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.88-90
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• 2003

The purpose of this study is to research and develop tin oxide-flash composite for lithium Ion polymer battery. Tin oxide is one of the promising material as a electrode active material for lithium Ion polymer battery (LIPB). Tin-based oxides have theoretical volumetric and gravimetric capacities that are four and two times that of carbon, respectively. We investigated cyclic voltammetry and charge/discharge cycling of SnO-flyash/SPE/Li cells. The first discharge capacity of SnO-flyash composite anode was 720 mAh/g. The discharge capacity of SnO-flyash composite anode 412 and 314 mAh/g at cycle 2 and 10 at room temperature, respectively. The SnO-flyash composite anode with PVDF-PMMA-PC-EC-$LiClO_4$ electrolyte showed good capacity with cycling.

• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.230-233
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• 2002

A new lithium niobate optical modulator with a polymer buffer layer on Ni in-diffused optical waveguide is proposed for the fist time, successfully fabricated and examined at a wavelength of 1.3 ${\mu}m$. The experimental results show that the measured half-wave voltage is of ${\sim}10$ V and the total measured fiber-to-fiber insertion loss is of ${\sim}-6.4$ dB for a 40 mm long waveguide at a wavelength of 1.3 ${\mu}m$, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.331-334
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• 2000

The organic electroluminescent(EL) device has gathered much interest because of its large potential in materials and simple device fabrication. We fabricated EL devices which have a blended single emitting layer containg poly(Nvinylcarbazole)[PVK] and poly(3-dodecylthiophene)[P3DoDT]. The molar ratio between P3DoDT and PVK changed with 1:0, 2:1 and 1:1. To improve the external quantum efficiency of EL devices, we applied insulating layer, LiF layer between polymer emitting layer and AI electrode. All of the devices emit orange-red light and it's can be explained that the energy transfer occurs from PVK to P3DoDT. Within the molar ratio 1:0, 2:1 and 1:1, the energy transfer was not saturated, which results in the not appearance of PVK emission in the blue region. In the voltage-current and voltage-light power characteristics of devices applied LiF layer, current and light power drastically increased with increasing with applied voltage. In the consequence of the result, the light power of the device have a molar ratio 1:1 with LiF layer was about 10 times larger than that of the device without PVK at 6V.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.968-970
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• 1999

The trend of increasing of portable electric devices and demand for global environmental conservation have demands the development of high energy density rechargeable batteries. Lithium polymer battery has excellent theoretical energy density and energy conversion efficiency. Lithium polymer battery, included solid polymer electrolyte(SPE), can be viewed as a system suitable for wide applications from thin film batteries for microelectronics to electric vehicle batteries. The purpose of this paper is to research and development of flyash anode for lithium polymer battery. We investigated AC impedance response and charge/discharge characteristics of flyash/SPE/Li cells. The radius of semicircle associated with the interfacial resistance of flyash/SPE/Li cell increased very slowly during discharge process from 3.11V to 0.478V. And then the cell resistance was decreased at discharge process from 10% SOC to 0% SOC. Also, The radius of semicircle associated with the interfacial resistance of flyash/SPE/Li cell decreasing very slowly during charge process. And then the cell resistance was increased after 20th discharge precess. The discharge capacity based on flyash of 1st and 20th cycles was 276mAh/g and 143mAh/g.

• KIEE International Transactions on Electrophysics and Applications
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• v.11C no.2
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• pp.37-41
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• 2001

In this study, organic electroluminescent devices with the ITO/TPD/Alq$_3$/cathode structure, using various materials of Al, Mg:Ag, Al:Li, MgF$_2$/Al, and LiF/Al as cathodes, were fabricated. We investigated the electrical and optical properties of the devices as follow: current density-voltage(J-V), luminance-voltage(L-V) and luminous efficiency-voltage curves. The bilayer cathodes with LiF/Al and MgF$_2$/Al exhibited better device performance than the other cathodes. It is considered that the improved performance of the organic electroluminescent devices is attributable to the lowering of driving voltage caused by the enhanced electron injection. The alkaline-earth fluorides are desirable materials to improve the performance of the EL devices with the Al cathode, and high luminous efficiency was achieved.

• Journal of Electrical Engineering and Technology
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• v.7 no.6
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• pp.932-939
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• 2012

This paper presents an equivalent circuit model of a LIPB (Li-Ion Polymer battery) for Hybrid Electric Vehicles (HEVs). The proposed equivalent circuit can be used to predict the charging/discharging characteristics in time domain as well as the impedance characteristic analysis in frequency domain. Based on these features, a one-cell model is established as a function of Depth of Discharge (DoD), and a 48-cell model for a battery pack was also established. It was confirmed by experiment that the proposed model predict the discharging and impedance (AC) characteristics quite accurately at different constant current levels. To check the usefulness of the proposed circuit, the model was used to simulate a motor driving circuit with an Insulated Gate Bipolar Transistor (IGBT) inverter and Brushless DC (BLDC) motor, and it is confirmed that the model can calculate the battery voltage fluctuation in time domain at different DoDs.

• Journal of Veterinary Clinics
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• v.25 no.6
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• pp.471-475
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• 2008

The present study was performed to elucidate the therapeutic effect by aquapuncture with bee-venom (apitoxin) for treatment of canine pyoderma. The total 8 dogs with pyoderma were divided into 2 groups as control (antibiotics group: 4 dogs) and experimental groups (apitoxin group: 4 dogs). Antibiotics group was treated with bathing and antibiotics, while apitoxin group was treated with bathing and aquapuncture with apitoxin at Fei Shu (BL13), Wei Zhong (BL40), Da Zhui (GV14), Zu San Li (ST36), He Gu (LI04), Qu Chi (LI11), and San Yin Jiao (SP06). Based on the results of changes in clinical symptoms, total leukocyte counts, neutrophil/lymphocyte ratios and histopathological findings, antibiotics and apitoxin groups were all effective for treatment of canine pyoderma, and significant differences were not detected between the groups. It was suggested that apitoxin might be used as an alternative method to antibiotics for treatment of canine pyoderma.

• Journal for History of Mathematics
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• v.31 no.6
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• pp.273-289
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• 2018

The KaiFangFa開方法 of traditional mathematics was completed in ${\ll}$JiuZhang SuanShu九章算術${\gg}$ originally, and further organized in Song宋 $Yu{\acute{a}}n$元 dinasities. The former is the ShiSuoKaiFangFa釋鎖開方法 using the coefficients of the polynomial expansion, and the latter is the ZengChengKaiFangFa增乘開方法 obtaining the solution only by some mechanical numerical manipulations. ${\ll}$SanHak JeongEui算學正義${\gg}$ basically used the latter and improved the estimate-value array by referring to the written-calculation in ${\ll}$ShuLi JingYun數理精蘊${\gg}$. As a result, ZengChengKaiFangFa was more refined so that the KaiFangFa algorithm is more consistent.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.6
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• pp.471-476
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• 2022

In this paper, we propose an object detection using a 4D imaging radar, which developed to solve the problems of weak cameras and LiDAR in bad weather. When data are measured and collected through a 4D imaging radar, the density of point cloud data is low compared to LiDAR data. A technique for clustering objects and extracting the features of objects through voxels in the cluster is proposed using the characteristics of wide distances between objects due to low density. Furthermore, we propose an object detection using the extracted features.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1034-1038
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• 1995

The purpose of this study is to research and develop $TiS_2$ composite cathode for lithium polymer battery(LPB). $TiS_2$ electrode represent a class of insertion positive electrode used in Li secondary batteries. In this study, we investigated preparation of $TiS_2$ composite cathode and AC impedance response of $TiS_2$ composite/SPE/Li cells as a function of state of charge(SOC) and cycling. The resistance of B type cell using $TiS_2PEO_8LiClO_4PC_5EC_5$ composite cathode was lower than that of A type cell using $TiS_2PEO$ composite cathode. The cell resistance of B type cell is high for the first few percent discharge, decreases for midium discharge and then increases again toward the end of discharge. We believe the magnitude of the cell resistance is dominated by passivation layer impedance and small cathode resistance. AC impedance results indicate that the cell internal resistance increase with cycling, and this is attributed to change of passivation layer impedance with cycling. The passivation layer resistance($R_f$) of B type cell decreases for the 2nd cycling and then increases again with cycling. Redox coulombic efficiency of B type cell was about 141% at 1st cycle and 100% at 12th cycle. Also, $TiS_2$ specific capacity was 115 mAh/g at 12 cycle.