• 제목/요약/키워드: Two electrode system

검색결과 288건 처리시간 0.03초

Hybrid between Inorganic Material and Biological Photosystem1 for Light Energy Application

  • 김영혜;남기태
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.272-272
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    • 2013
  • The attractive features of photosynthetic reaction center proteins for energy application make them useful in solar energy conversion to hydrogen fuel or electrical energy. Almost unity charge separation quantum yield and its rapid speed of ~1ns, absorbance region in visible light (480~740 nm) and high proportion of photosynthetically active solar energy of 48.5% allowed photosystem1 to exploited as a bio-material for photo-energy devices. Directionality of photosystem1 in electron transfer can solve main problem in two-step water splitting process where back reaction deteriorates the overall efficiency. In the study, photosystem1 was extracted from spinach and the photo-induced excited electron in the reaction center was utilized in various field of light energy application. First, hydrogen evolving system realized by photodeposition of platinum at the end of the electron transfer chain, with combining specific semiconductor to oxidize water in the first step of Z-scheme. The evaluation by gas-chromatography demonstrated hydrogen evolution through the system. For the further application of photoelectrical material on electrode, photosystem1 have been controlled by copper ion, which is expected to assemble photosystem in specific orientation followed by maximized photoelectrical ability of film. The research proposed concrete methods for combining natural protein and artificial materials in one system and suggested possibility of designing interface between biological and inorganic materials.

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비접촉식 심장활동 모니터링 기능 의복형 웨어러블 시스템의 모듈 효과 탐색 (Effect of Module Design for a Garment-Type Heart Activity Monitoring Wearable System Based on Non-Contact Type Sensing)

  • 구혜란;이영재;지선옥;이승표;김경남;강승진;이정환;이주현
    • 한국의류학회지
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    • 제39권3호
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    • pp.369-378
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    • 2015
  • Various forms of wearable bio-signal monitoring systems have been developed recently. Acquisition of stable bio-signal data for health care purposes needs to be unconscious and continuous without hindrance to the users' daily activities. The garment type is a suitable form of a wearable bio-signal monitoring system; however, motion artifacts caused by body movement degrade the signal quality during the measurement of bio-signals. It is crucial to stabilize the electrode position to reduce motion artifacts generated when in motion. The problems with motion artifacts remain unresolved despite their significant effect on bio-signal monitoring. This research creates a foundation for the design of garment-type wearable systems for everyday use by finding a method to reduce motion artifacts through modular design. Two distinct garment-type wearable systems (tee-shirt with a motion artifact-reducing module (MARM) and tee-shirt without a MARM) were designed to compare the effects of modular design on the measurement of heart activity in terms of electrode position displacement, signal quality index value, and morphological quality. The tee-shirt with MARM showed superior properties and yielded higher quality signals than the tee-shirt without MARM. In addition, the tee-shirt with MARM showed a better repeatability of the heart activity signals. Therefore, a garment design with MARM is an efficient way to acquire stable bio-signals while in motion.

이동형 심전도 신호의 잡음 제거 및 유사도 평가 (Noise Reduction and Estimating the Similarity of Ambulatory ECG Signals)

  • 신승원;이정환;이강휘;김동준;김경섭
    • 전기학회논문지
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    • 제57권3호
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    • pp.507-513
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    • 2008
  • In this study, we develope an ambulatory ECG acquisition system by implementing a patch-style and wireless electrode. To alleviate the inherent noisy characteristics of the mobile signal, we apply a matched filter and concurrently detect R-peak values. Moreover, the measure for resolving shape distance is computed to estimate the relative similarity between two ECG signals and to decide whether the abnormal characteristics in ECG exist or not.

펄스 전압을 이용한 인바 합금의 미세 전해가공 (A study of Pulse EMM for Invar alloy)

  • 김원묵;백승엽;이은상;탁용석
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.560-563
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    • 2004
  • Invar is a compound metal of Fe-Ni system and contain 36% Ni. The most distinction characteristic of Invar is the coefficient of thermal expansion is 1.0 10$^{-6}$ /$^{\circ}C$. That is a tenth of general steel material. This low thermal expansion characteristic of Invar is applied to the missile, aircraft, monitor CRT and frontier display's shadow mask such as FED and OLED. The usage of the Invar shadow mask for display is increasing due to the requirement of larger size and flatness monitor. The Invar shadow mask is machined by two ways electro-forming and laser now. However the electro-forming takes a too long time and the laser machining is accompanied with Burr. In this study, PEMM(pulse electrochemical micro machining) is conducted to machine the micro hole to the Invar and 80${\mu}{\textrm}{m}$ hole was machined.

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소아에서의 치과전기마취 : 증례보고 (DENTAL ELECTRONIC ANESTHESIA IN CHILDREN : A CASE REPORT)

  • 이은영;이창섭;이상호
    • 대한소아치과학회지
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    • 제21권2호
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    • pp.525-532
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    • 1994
  • The purpose of this report was to evaluate the effect of Dental Electronic Anesthesia on pain inhibition for clinical use. The subject for this study were 30 children whose Frankl behavioral rate is positive. The subjects was divided into two groups, the first group described by control group and the second group described by experimental group anesthetized with Dental Electronic Anesthetic device. And then three kind of treatments were done : extraction of deciduous teeth, application of rubber dam, cavity preparation for preventive resin restoration. 3M Dental Electronic Anesthesia System was used for this study : its electric impulse stimulate the skin surface by external electrode pads. The results were as follows. 1. Degree of the pain & the apprehension decreased in experimental group. 2. Degree of the pain & the apprehension showed statistical differences among three treatments procedures in the control group but, not showed statistical differences in the experimental group.

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비친수성유기물질(HOC)로 오염된 토양의 정화를 위한 동전기-생물활성화공정의 개발

  • 양지원;김상준;박지연;이유진;기대정
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 추계학술발표회
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    • pp.326-329
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    • 2003
  • When an electrokinetic process is applied to a HOC-contaminated soil, hybrid types combined with soil flushing, chemical oxidation, and bioremediation are generally used. Especially when the electrokinetic process is combined with bioremediation, the hybrid technology can solve several limits of bioremediation such as low microbial mobility, low soil temperature, and shortage of nutrients in subsurface circumstance. Because microbial surface is charged negatively, the microorganism moves from cathode to anode under electrical field. In this study, mixed culture mainly-consisted by Pseudomonas sp. was applied to remediate pentadecane-contaminated kaolinite with particle size less than 300${\mu}{\textrm}{m}$. This remediation system was named ‘electrokinetic bioaugmentation’ and consisted of model aquifer, electrode reservoirs, bioreactor, power supply, and pump. The mixed culture above 0.5 of optical density in bioreactor was supplied to two reservoirs and penetrated soil when the electric current was applied. To enhance the removal efficiency, the optimal medium composition, electric current, and voltage were investigated.

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입자분산계 ER유체의 빙햄특성 고찰 (A Study on Bingham Characteristics of Particle Dispersive Electro-Rheological Fluid)

  • 장성철;이선의;김태형;박종근;염만오
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2000년도 추계학술대회 논문집
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    • pp.178-183
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    • 2000
  • Electrorheological(ER) effect on the dispersive system of polarizable fine powder/dielectric oil has been investigated. The electrical and rheological properties of zeolite and starch based ER fluid were reported. The ER fluids were constructed by mixing zeolite and starch power with two different dielectric oils. Yield stress of the fluids were measured on the couette cell type rheometer as a function of electric fields, particle concetrations, and temperatures. The electric field is applied by high voltage DC power supply. The outer cup is connected to positive electrode(+) and the bob becomes ground(-). And the temperatures the viscosity(or shear stress) versus shear rates were measured. In this experiment shear rates were increased from 0 to $200s^{-1}$ in 2 minutes.

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저온 고체산화물연료전지 구현을 위한 다층 나노기공성 금속기판의 제조 (Development of Metal Substrate with Multi-Stage Nano-Hole Array for Low Temperature Solid Oxide Fuel Cell)

  • 강상균;박용일
    • 한국세라믹학회지
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    • 제42권12호
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    • pp.865-871
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    • 2005
  • Submicron thick solid electrolyte membrane is essential to the implementation of low temperature solid oxide fuel cell, and, therefore, development of new electrode structures is necessary for the submicron thick solid electrolyte deposition while providing functions as current collector and fuel transport channel. In this research, a nickel membrane with multi-stage nano hole array has been produced via modified two step replication process. The obtained membrane has practical size of 12mm diameter and $50{\mu}m$ thickness. The multi-stage nature provides 20nm pores on one side and 200nm on the other side. The 20nm side provides catalyst layer and $30\~40\%$ planar porosity was measured. The successful deposition of submicron thick yttria stabilized zirconia membrane on the substrate shows the possibility of achieving a low temperature solid oxide fuel cell.

바이오센서에 의한 뿌리 원형질막에서의 $H^ +-ATPase $의 활성측정 (Expression of Plasma Membrane $H^ +-ATPase $ in the Roots of Plants Under Low Temperature)

  • 천병수;정갑채;유종수
    • KSBB Journal
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    • 제17권1호
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    • pp.59-62
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    • 2002
  • 본 연구에서는 특히 환경변화에 민감한 오이, 호박을 선택하여 저온 스트레스에 의한 기작 반응을 인지하는 이온 채널들의 식물에 가해지는 수송능력의 변화에 따른 능동 운송과 스트레스 감응 능력에 따른 생리학적 규명을 위해 시료 처리가 복잡하고 장시간 소요되는 종래법에서 탈피하고자 바이오센서에 의한 진속, 간단, 경제적 측정법을 도입하였다. 시료한 개를 측정하는데 걸리는 시간은 3분이 소요되며 센서법과 종래법과의 측정결과 사이에 좋은 상관치를 나타내었다.

보일러용 정전용량형 수위센서 시스템 개발 (Development of Capacitive Water Level Sensor System for Boiler)

  • 이영태;권익현
    • 반도체디스플레이기술학회지
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    • 제20권3호
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    • pp.103-107
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    • 2021
  • In this paper, a capacitive water level sensor for boilers was developed. In order to accurately monitor the water level in a high-temperature boiler that generates a lot of precipitates, the occurrence of precipitates on the surface of the water level sensor should be small, and a sensor capable of measuring even if the sensor surface is somewhat contaminated is required. The capacitive water level sensor has a structure in which one of the two electrodes is insulated with Teflon coating, and the stainless steel package of the water level sensor is brought into contact with the water tank so that the entire water tank becomes another electrode of the water level sensor. A C-V converter that converts the capacitance change of the capacitive water level sensor into a voltage change was developed and integrated with the water level sensor to minimize noise. The performance of the developed capacitive water level sensor was evaluated through measurement.