• 제목, 요약, 키워드: Flat electrode method

검색결과 45건 처리시간 0.037초

평판접지 전극방법을 이용한 콘크리트의 전기비저항 특성 분석 (Analysis of Electrical Resistivity Characteristics of Concrete by Using Flat Electrode Method)

  • 박창선;박해원;이강훈;정진훈
    • 한국도로학회논문집
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    • v.19 no.3
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    • pp.57-63
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    • 2017
  • PURPOSES : The pole electrode method damaged the concrete pavement on inserting the electrode into the pavement surface. This study examined the feasibility of the flat electrode method to observe the concrete pavement instead of the pole electrode method and analyzed the resistivity characteristics of the concrete by performing laboratory tests. METHODS : The resistivity of the concrete specimens manufactured with three different mixing ratios (38.50%, 39.50%, and 40.50%) were measured using the pole and flat electrode methods according to the concrete age (7 and 28 days) and electrode spacing (20 mm, 30 mm, and 40 mm). RESULTS :In both pole and flat electrode methods, the resistivity increased with increasing fine aggregate proportion regardless of the concrete age. The resistivity measured at a concrete age of 28 days was slightly larger than that measured at 7 days. In the case of a concrete age of 7 days, the resistivity measured by the flat electrode method was larger than that measured by the pole electrode method. The difference disappeared at 28 days. CONCLUSIONS :The results suggest that the flat electrode method can replace the pole electrode method because the resistivity measured by both methods was similar. Hence, the development of a technology to apply the flat electrode method to actual concrete pavement is necessary.

Piezofilm 을 이용한 저주파 평면 스피커의 설계 (Design of Low Frequency Flat Speaker by Piezofilm)

  • 황준석;이성;김승조
    • 한국복합재료학회:학술대회논문집
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    • pp.191-194
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    • 2000
  • In this study, experimental verification of performance of flat speaker has been conducted. The piezofilm (PVDF) actuator has been designed to prevent the distortion of sound and make the frequency response of radiated sound flat. The electrode pattern of piezofilm actuator is optimized to satisfy the design objective. The formulation of design method is based on the coupled finite element and boundary element method and electrode pattern is optimized by genetic algorithm. The flat speaker with optimized piezofilm actuator has been manufactured. The sound pressure level at the distance of 50cm is measured using microphone and compared with the result of numerical simulation.

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침지 및 직립 평판형 MFC 스택에서 전극연결 방식에 따른 전기발생량 비교 (Electricity Generations in Submerged-flat and Stand-flat MFC Stacks according to Electrode Connection)

  • 유재철;박영현;이태호
    • KEPCO Journal on Electric Power and Energy
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    • v.2 no.4
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    • pp.589-593
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    • 2016
  • 미생물연료전지(Microbial Fuel Cell; MFC)는 전기화학활성미생물로 불리는 미생물을 촉매로 이용하여, 유/무기물의 산화환원 반응을 통해서 전기에너지를 생산할 수 있는 장치이다. 단일 MFC에서 발생하는 낮은 전기생산량을 극복하기 위해, 다수의 형태의 MFC를 직렬 또는 병렬로 연결하는 방법이 연구되고 있다. 본 연구에서는 6개의 단위 막전극접합체(Separator Electrode Assembly; SEA)로 구성된 침지평판형과 직립평판형 MFC 스택을 운전하였다. 단위 MFC와 MFC 스택의 전기발생량을 비교하였으며, 이를 통해서 MFC의 최적 스택기술을 확보하기 위한 기초자료로 활용하고자 하였다. 모든 SEA가 산화전극부를 공유하고 있는 침지평판형 MFC의 경우, 직렬과 병렬을 함께 사용할 경우, 단일 연결 방식을 사용하는 것보다 전압의 손실이 더 크게 나타났으며, 단일 연결방법 중 병렬연결 하는 것이 손실을 최소화 할 수 있는 것으로 나타났다. 직립평판형 MFC의 경우, 산화전극부를 공유하고 있는 SEA만 직렬 연결할 경우에는 전압의 손실이 크게 나타났으며, 산화전극부를 공유하고 있는 SEA간에 병렬 연결 후, 병렬 연결된 SEA를 직렬연결하는 방식이 전압의 손실을 최소화 할 수 있을 것으로 나타났다.

Electrochemical Performance of Ti-Si Alloy Anode using Nodule Type Current Collector

  • Shin, Min-Seon;Park, Jung-Bae;Lee, Sung-Man
    • 전기화학회지
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    • v.20 no.4
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    • pp.61-66
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    • 2017
  • The cycle performance of Ti-Si alloy anode material for Li-ion batteries has been investigated as a function of loading level of electrode using a nodule type of substrate, in which the current collector of flat foil is also used for comparison. The Ti-Si alloy powders are prepared by mechanical alloying method. The electrodes with the nodule type of current collector exhibit enhanced cycling performance compared to those using the flat foil because the alloy particles are more strongly adhered to substrate and the stress caused by lithiation and delithiation reaction can be effectively relaxed by nodule-type morphology. It appears, however, that the cycle performance is critically dependent on the loading level of electrode, even when the nodule type of current collector is applied. With high loading level, cracks are initiated at surface of electrode due to a steep stress gradient through the electrode thickness during cycling, leading to capacity fading.

복합재료 평판과 압전필름 작동기를 이용한 저음용 평판 스피커 설계 (Design of Loudspeaker using Composite Plate and Piezofilm Actuator)

  • 황준석;김승조
    • 한국복합재료학회:학술대회논문집
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    • pp.124-129
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    • 1999
  • In this study, a design method for the flat sound radiator is developed to make new sound radiator system, whose shape is much thinner than that of conventional loudspeaker. Piezofilm (PVDF) is used as actuators of flat sound radiator. To avoid the distortion of sound radiated from flat sound radiator, the frequency response of radiated sound to be flat is taken as the design objective. The electrode pattern and orientation angle of piezofilm actuator is optimized to satisfy the design objective. The formulation is based on the coupled finite element and boundary element method. Genetic algorithm is used in the optimization process, which is useful in the optimization of discrete design variables. Frequency response with optimized piezofilm actuator is made flat enough to satify the design objective. For the enhancement of sound power, double-layered piezofilm actuators are also considered. The sound power with double-layered actuator becomes larger than that with single-layered actuator as expected.

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평판 작동기의 최적화를 통한 평면 스피커 설계 (Flat Speaker Design by Optimization of Plane Actuator)

  • 김승조;황준석
    • 한국음향학회:학술대회논문집
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    • pp.237-242
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    • 1999
  • In this study, a design method using plane actuator is developed to make new speaker system, whose shape is much thinner than that of conventional loudspeaker. Piezofilm(PVDF) is used as plane actuator of flat speaker. To avoid the distortion of sound radiated from flat speaker, the frequency response of radiated sound to be flat is taken as the design objective. The electrode pattern and orientation angle of piezofilm actuator is optimized to satisfy the design objective. The formulation is based on the coupled finite element and boundary element method. Genetic algorithm is used in the optimization process, which is useful in the optimization of discrete design variables. Frequency response with optimized piezofilm actuator is made flat enough to satisfy the design objective. For the enhancement of sound power, double-layered piezofilm actuators are also considered. The sound power with double-layered actuator becomes larger than that with single-layered actuator as expected.

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한지의 산성도 측정을 위한 비파괴적 방법의 적용 (The application of a nondestructive method to measure the acidity of Korean papers)

  • 이혜윤;정용재;이규식;한성희
    • 보존과학연구
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    • pp.21-47
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    • 1999
  • According to damage of papers by the chemical cause, papers become to acidify. Among the 3 kinds of method measuring the acidity of paper, one was nondestructive method measuring the surface of the paper by flat type electrode and the others were destructive methods measuring directly by cold water extract method and hot water extract method. In case of the cellulolytic cultural properties, the latter methods were not applied because those methods must bedissociated papers. To measure the paper acidity nondestructively, we investigated the correlation of the nondestructive method and the destructive methods. The conclusions are as follows. 1) In the relationship of the cold water extract method and the hot water extract method, It was indicated that the pH measured by the hot water extract method was high quality printing paper 0.08, rough printing paper 0.13, and Korean paper 0.29 higher than that by the cold water extract method.2) In the relationship of the cold water extract method and the surface measurement method, It showed that the pH value measured by the cold water extract method was high quality printing paper 1.86, rough printing paper 0.80,and Korean paper 0.58 higher than value that by the surface measurement.3) In the relationship of the hot water extract method and the surface measurement method, It showed that the pH value measured by the hot ABSTRACT water extract method was high quality printing paper 1.78, rough printing paper 0.66, and Korean paper 0.29 higher than that by the surface measurement. From the above-mentioned results, the pH value measured by the surface measurement was need to high about 1.78∼1.86 in high quality printing paper, 0.66-0.80 in rough printing paper, and 0.29∼0.58 in Korean paper and the surface measurement with flat type electrode was very available to measure the acidity of Korean papers actually.

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발굴현장 수습 유물 보존처리 (On-site conservation of a gilt bronze crown)

  • 유재은
    • 보존과학연구
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    • pp.49-64
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    • 1999
  • According to damage of papers by the chemical cause, papers become to acidify. Among the 3 kinds of method measuring the acidity of paper, one was nondestructive method measuring the surface of the paper by flat type electrode and the others were destructive methods measuring directly by cold water extract method and hot water extract method. In case of the cellulolytic cultural properties, the latter methods were not applied because those methods must bedissociated papers. To measure the paper acidity nondestructively, we investigated the correlation of the nondestructive method and the destructive methods. The conclusions are as follows. 1) In the relationship of the cold water extract method and the hot water extract method, It was indicated that the pH measured by the hot water extract method was high quality printing paper 0.08, rough printing paper 0.13, and Korean paper 0.29 higher than that by the cold water extract method.2) In the relationship of the cold water extract method and the surface measurement method, It showed that the pH value measured by the cold water extract method was high quality printing paper 1.86, rough printing paper 0.80,and Korean paper 0.58 higher than value that by the surface measurement.3) In the relationship of the hot water extract method and the surface measurement method, It showed that the pH value measured by the hot ABSTRACT water extract method was high quality printing paper 1.78, rough printing paper 0.66, and Korean paper 0.29 higher than that by the surface measurement. From the above-mentioned results, the pH value measured by the surface measurement was need to high about 1.78∼1.86 in high quality printing paper, 0.66-0.80 in rough printing paper, and 0.29∼0.58 in Korean paper and the surface measurement with flat type electrode was very available to measure the acidity of Korean papers actually.

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프린팅 전자소자용 잉크젯 기술과 소재 (The role of functional materials and inkjet printing technology for printable electronics)

  • 류병환;최영민
    • 대한기계학회:학술대회논문집
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    • pp.446-450
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    • 2007
  • It is strongly expected that inkjet printing method will be play and important role on printable electronics such as 3D integration of embedded ceramic devices(capacitor, resistor, inductor and electrode or circuit), Si-TFT and organic TFT including display C/F, RFID, FPCB, and etc. A inkjet printing method had been center of attention to strengthen the competitiveness of flat panel display on market and to open the new world of manufacturing process of printable electronics. We will survey the industrial tendency of printable electronics and flat panel display including some examples of inkjet printing and present the considerable points of inkjet printing method and some role of materials for successful inkjet printing.

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500W 급 연료극 지지체 평관형 고체산화물연료전지 스택의 운전 특성 (Operating Characteristics of Advanced 500W class Anode-supported Flat Tubular SOFC stack in KIER)

  • 임탁형;김관영;박재량;송락현;이승복;신동열
    • 한국에너지공학회:학술대회논문집
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    • pp.193-198
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    • 2007
  • KIER has been developing the anode supported flat tubular SOFC stack for the intermediate temperature $(700{\sim}800^{\circ}C)$ operation. for this purpose, we have first fabricated anode supported flat tubular cells by the optimization between the current collecting method and the induction brazing process. After that we designed the compact fuel & air manifold by adopting the simulation technique to uniformly supply fuel & air gas and the unique seal & insulation method to make the more compact stack. For making stack, the prepared anode-supported flat tubular cells with effective electrode area of $90cm^2$ of connected in series with 12 modules, in which one module consists of two cells connected in parallel. The performance of stack in 3 % humidified $H_2$ and air at $800^{\circ}C$ shows maximum power of 507 W. Through these experiments, we obtained basic & advanced technology of the anode-supported flat tubular cell and established the proprietary concept of the anode-supported flat tubular SOFC stack in KIER.

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