• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2007년도 춘계학술대회 논문집
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• pp.3-6
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• 2007

The Light brightness is to enhance the luminescence efficiency of phosphor including conductive material. In preparing the anode layer, phosphors mixed with conductive material prepared with pastes of polymer resin using by screen printing method. When the prepared anode layer bombarded by cold electron from emitter of cathode, it give rise to form the secondary electron from those of conductive materials such as ITO powder. Furthermore, we are expect to enhance the luminescence efficiency more than without conductive material.

• 한국산학기술학회논문지
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• 제16권4호
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• pp.2770-2776
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• 2015

최근 인체 중심의 근거리, 저전력 무선통신을 이용한 다양한 사물인터넷 어플리케이션이 출현함에 따라 효율적으로 무선에너지를 방사시킬 수 있는 소형 웨어러블 안테나 개발의 필요성이 대두되고 있다. 본 논문에서는 전도성 실로 일상의류에 간편하게 구현할 수 있는 웨어러블 안테나의 특성을 시물레이션 및 측정 결과를 바탕으로 분석하였다. 제안한 안테나는 펠트 천 위에 전도성 실을 직교로 엮은 형태로 구현하였으며 full-wave 전파 시물레이션 툴을 이용한 parametric study를 바탕으로 구조 변화에 따른 안테나 임피던스, 공진 주파수 및 방사 효율 등의 변화를 관찰하였다. 그 결과, 안테나 방사효율이 전도성 실 사이 간격이 0.25mm에서 3mm로 증가함에 따라 67.5%에서 70.4%로 증가함을 확인하였다. 이를 통해 적은 양의 전도성 실 재질을 이용해도 좋은 방사효율의 안테나를 구현할 수 있다는 결론을 도출할 수 있다. 실제 제작된 안테나를 통해 구한 측정값도 유사한 경향을 보였다.

• 전기학회논문지
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• 제68권1호
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• pp.207-214
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• 2019

A large-capacity wireless power system is a technology that transmits electric power of kW or more in a noncontact type. Electric cars, electric buses, and electric railways. In order to increase the power transmission efficiency, a resonance method using a frequency of kHz is applied and the efficiency is 80 ~ 90%. In this case, the loss is 10 ~ 20% other than efficiency, and corresponds to several hundreds of W to several kW in kW class wireless power transmission. 35 kW wireless feed system environment, and induced current in the nearby conductive part was measured. As a result of analysis, it was confirmed that induction phenomenon is higher as the loop configuration of the conductive part per area is dense. The increase of the induced current in the mesh loop is characterized by the density of the nearby conductive part having a permeability per unit area. The concentration of the magnetic field by the permeability is increased and the induction phenomenon causing the induction current is increased. It was confirmed that induction phenomenon increases by about 2.7 times when 9 times dense structure is formed.

• 한국전기전자재료학회논문지
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• 제35권3호
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• pp.203-214
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• 2022

Thermoelectric (TE) heating and cooling devices, which are able to directly convert thermal energy into electrical energy and vice versa, are effective and have exhibited a potential for energy harvesting. With the increasing consumer demands for various wearable electronics, organic-based TE composite materials offer a promise for the TE devices applications. Conductive polymers are widely used as flexible TE materials replacing inorganic materials due to their flexibility, low thermal conductivity, mechanical flexibility, ease of processing, and low cost. In this review, we briefly introduce the latest research trends in the flexible TE technology and provide a comprehensive summary of specific conductive polymer-based TE material fabrication technologies. We also summarize the manufacture for high-efficiency TE composites through the complexation of a conductive polymer matrix/inorganic TE filler. We believe that this review will inspire further research to improve the TE performance of conductive polymers.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.441-441
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• 2014

The characteristics of hybrid conductive films based on multilayer graphene and silver grid have been investigated for the high-performance and flexible organic solar cells. The hybrid conductive films have been prepared on glass and polyethylene terephthalate (PET) substrates using conventional photolithography process and transfer process of graphene. The optical and electrical properties of prepared conductive films show transmittance of 87% at 550nm and sheet resistance of $28{\Omega}/square$. The electromechanical properties were also investigated in detail to confirm the flexibility of the hybrid films. OSCs have been fabricated on the hybrid conductive films based on graphene and silver grid on glass substrate. The power conversion efficiency of 2.38%, a fill factor of 51%, an open circuit voltage of 0.58V and a short circuit current of $8.05mA/cm^2$ were obtained from the device on glass substrate. The PCE was enhanced 11% compared with OSCs on the MLG films without silver grid.

• 한국전기전자재료학회논문지
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• 제32권3호
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• pp.179-186
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• 2019

This work investigated the effects of different conductive agents on the electrochemical properties of anodes. SiOx possesses high theoretical capacity and shows excellent cycle performance; however, the low initial coulombic efficiency and poor electrical conductivity limit its applications in real batteries. In this study, electrodes were fabricated using two different conductive agents, and the resulting physical and electrochemical properties were analyzed. SEM observations confirmed the formation of a CNT conductive network throughout the electrodes, while the electrical conductivity contributed to the electrode was confirmed by impedance measurements. Thus, the electrode fabricated with the CNT conductive agent showed greater capacity and superior cycle performance than did the electrode fabricated using the DB conductive agent.

• Journal of the Korean Wood Science and Technology
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• 제23권4호
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• pp.46-53
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• 1995

The anatomy of Korean diffuse-porous woods, 36 families, 75 genera, 145 species, 215 specimens was described and analyzed. Sixteen wood anatomical characters, habit and phenology factors were determined by simple correlation and principal component analysis. Strong positive correlations were found between vessel element length and fiber length, ray width and ray height, simple pits of fiber wall and paratracheal parenchyma distribution. The results of principal component analysis (PCA) disclose the primitive characteristics and the direction of xylem evolution of Korean diffuse-porous woods. The xylem evolution scenario for Korean dicotyledonous woods is considered to be developed in the direction of decreasing trends of vessel frequency, vessel element length, and length/diameter(L/D) ratio of vessel element but increasing trends of vessel diameter, fiber length/vessel element length(F/V) ratio, libriform wood fibers, simple perforation, and homogeneous ray composition. Increase of vessel diameter and decrease of vessel frequency seem to be related to the improvement of conductive efficiency, and increase of the vessel element length and occurrence of scalariform perforation in vessel element may be related to enhanced of conductive safety. Also the libriform wood fibers and ray features appear to have relationship with mechanical support and nutrient metabolism, respectively.

• Journal of Welding and Joining
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• 제20권1호
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• pp.76-82
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• 2002

In these days, many advanced nations have enforced import restrictions against things emitting electromagnetic wave which has report that it is so harmful. In general, electromagnetic wave is composed of electric wave and magnetic wave. The reflection of electromagnetic wave is mainly reflected by conductive materials and the magnetism loss is generated by magnetic ferrite. The magnetism loss of ferrite is separated by eddy current loss, residual magnetism loss and hysteresis loss. Thermal sprayed coating is intended to manufacture because of simple processes and high efficient electromagnetic wave shielding. The high efficient thermal sprayed coatings were made from the magnetic ferrite materials that characterizes absorption of electromagnetic wave, and the electric conductive materials that characterize emitting of electromagnetic wave. This study was manufactured thermal sprayed coatings to improve absorption-efficiency, and measured the electromagnetic wave shielding efficiency. As the experimental results, high electromagnetic wave shield efficiency was obtained at wave frequency 2GHz to thermal sprayed ferrite coatings manufactured by size distribution range of spray powders, $38~88\mu\textrm{m}$.

• 전기학회논문지
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• 제67권3호
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• pp.448-453
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• 2018

PV module protective film plays an important role in protecting the solar cell from external environment by anti-hydrolysis polyester, UV resistance and mechanical properties. The backsheet was manufactured by using Roll-to-Roll dry laminating process. The backsheet structure is composed of 3 layers, which are PE, PET, and Fluorine polymer films. In this study, we have experimented the variation of thermal conductivities depending on MgO inputs 10% to 25% in order to confirm the dependence of the module efficiencies. High thermal conductive backsheet can increase the module output power efficiency because the heat is dissipated by spreading out the internal heat. Long-term environment weatherability tests were conducted for confirming 25 year reliability in the field such as PCT, UV, and power efficiency degradations. As the evaluation result, high thermal conductivity can be effective for increase of power efficiency of solar panel by using thermal conductive MgO masterbatch.

• Current Photovoltaic Research
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• 제9권2호
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• pp.31-35
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• 2021

Shingled module shows high ratio active area per total area due to more efficient packing without inactive space between cells. The module is fabricated by connecting the pre-cut cells into the string using electrically conductive adhesives (ECA). ECAs are used for electric and structural connections to fabricate the shingled modules. In this work, we investigated a correlation between ECA peel strength and the efficiency of pre-cut 5 cells module which are fabricated according to ECA interconnection conditions. The curing conditions are varied to determine whether ECA interconnection properties can affect module properties. As a result of the peel test, the highest peel strength was 1.27 N/mm in the condition of 170℃, the lowest peel strength was 0.89 N/mm in the condition of 130℃. The efficiency was almost constant regardless of the curing conditions at an average of 20%. However, the standard deviation of the fill factor increased as the adhesive strength decreased.