• 한국항행학회논문지
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• 제17권6호
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• pp.664-671
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• 2013

본 논문에서는 항공기내에서 전력을 무선으로 측정할 수 있는 AEMS(Zigbee electric power measurement monitoring system)시스템을 제안한다. AEMS시스템은 현재 상용화되고 있는 전력 측정 시스템을 분석하여 이를 보완하고 항공기내에서도 전력 변화를 쉽게 알 수 있도록 최근 가장 이슈가 되는 스마트폰과 모니터링 시스템을 연결하여 설계하였다. 또한, 실시간 전력 측정 시스템을 도입하여 전기 사용량을 실시간으로 제어함으로써 보다 실용성 있는 전력계측 시스템을 구축하였다.

• Journal of Multimedia Information System
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• 제2권3호
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• pp.249-254
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• 2015

This article considers the development of an integrated control and safety management system (ICSS) and its interfaces with an automated enterprise management system (AEMS) in light of the establishment of industrial enterprises with intelligent model of centralized management on the example of Kandym GPP.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.77-80
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• 2006

Chloromethylated polysulfone(CMPSf) and a number of mono- and diamine compounds were used to prepare anion-exchange membranes(AEMs) and an ionomer binder solution. The properties of the AEMs were investigated such as $OH^-$ conductivity, water content and dimension stability. Chloromethylation and amination of PSf were optimized in terms of the properties. Membrane-electrode assemblies were fabricated using anion-exchange membranes and the ionomer binder for solid alkaline fuel cells and direct borohydride fuel cells.

• 한국수소및신에너지학회논문집
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• 제33권3호
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• pp.209-218
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• 2022

Recently, research on the development of anion exchange membranes (AEMs) has received considerable attention from the scientific community around the world. Here, we fabricated a series of AEMs with branched structures with different alkyl spacers and conducted comparative evaluations. The introduction of these branched structures is an attempt to overcome the low ionic conductivity and stability problems that AEMs are currently facing. To this end, branched polymers with different spacer lengths were synthesized and properties of each membrane prepared according to the branched structure were compared. The chemical structure of the polymer was investigated by proton nuclear magnetic resonance, Fourier transform infrared, and gel permeation chromatography, and the thermal properties were investigated using thermogravimetric analysis. The branched anion exchange membrane with (CH₂)₃ and (CH₂)₆ spacers exhibited ionic conductivities of 8.9 mS cm^-1 and 22 mS cm^-1 at 90℃, respectively. This means that the length of the spacer affects the ionic conductivity. Therefore, this study showing the effect of the spacer length on the ionic conductivity of the membrane in the polymer structure constituting the ion exchange membrane is judged to be very useful for future application studies of AEM fuel cells.

• 멤브레인
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• 제32권6호
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• pp.411-426
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• 2022

다양한 장치에 대한 광범위한 의존으로 에너지는 현대 생활에서 중요한 역할을 하고 있다. 전통적인 에너지원은 많은 환경 및 건강 문제를 안고 있어, 환경과 건강에 미치는 영향을 최소화하면서 에너지 수요를 충족할 수 있는 대체 가능한 에너지원이 시급히 필요하다. 이러한 관점에서 연료전지, 특히 음이온 교환막 연료전지는 고가의 촉매를 사용하지 않는 빠른 반응속도, 컴팩트한 디자인, 수소 이외의 연료 선택 가능성 및 보다 저렴한 연료의 사용이 가능한 특성으로 인하여 다른 연료전지에 비해 큰 주목을 받고 있다. 그럼에도 이온전도성이 높고 화학적, 기계적으로 안정적인 음이온 교환막의 개발이 부진한 것이 주요 장애물이 되어 왔고, 그래핀 기반 고분자 복합막이 AEMFC용 전해질막으로 등장하게 되었다. 2D 구조, 높은 기계적 강도, 높은 내화학성 및 표면적과 같은 그래핀의 견고한 구조 및 물리적 특성은 음이온교환막의 성능 개선에 도움이 된다고 보고되고, 그래핀 및 그 유도체를 사용하는 전해질막의 연구가 중요하게 되었으나, 그래핀 재료의 높은 잠재력에도 지나친 응집 경향으로 나타나는 문제점이 지적되고 있어 그래핀 유도체의 표면 개질은 응집을 완화하고 그래핀이 가지는 잠재적 성능을 이끌어내는데 꼭 필요하다. 따라서 본 고에서는 그래핀과 유도체의 표면 개질과 연료 전지용 AEM 제조에서 그 역할에 초점을 맞추어서 논의하고자 한다.

• Journal of Electrochemical Science and Technology
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• 제8권3호
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• pp.183-196
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• 2017

The research efforts directed at advancing water electrolysis technology continue to intensify together with the increasing interest in hydrogen as an alternative source of energy to fossil fuels. Among the various water electrolysis systems reported to date, systems employing a solid polymer electrolyte membrane are known to display both improved safety and efficiency as a result of enhanced separation of products: hydrogen and oxygen. Conducting water electrolysis in an alkaline medium lowers the system cost by allowing non-platinum group metals to be used as catalysts for the complex multi-electron transfer reactions involved in water electrolysis, namely the hydrogen and oxygen evolution reactions (HER and OER, respectively). We briefly review the anion exchange membranes (AEMs) and electrocatalysts developed and applied thus far in alkaline AEM water electrolysis (AEMWE) devices. Testing the developed components in AEMWE cells is a key step in maximizing the device performance since cell performance depends strongly on the structure of the electrodes containing the HER and OER catalysts and the polymer membrane under specific cell operating conditions. In this review, we discuss the properties of reported AEMs that have been used to fabricate membrane-electrode assemblies for AEMWE cells, including membranes based on polysulfone, poly(2,6-dimethyl-p-phylene) oxide, polybenzimidazole, and inorganic composite materials. The activities and stabilities of tertiary metal oxides, metal carbon composites, and ultra-low Pt-loading electrodes toward OER and HER in AEMWE cells are also described.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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• pp.8-13
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• 2000

Die polishing technology is very critical to determine quality and performance of the final products. Die polishing processes have not been automated because the automation requires a great deal of experience and skill of experts. Thus, to implement a fully automated polishing process, the development of polishing status monitoring system replacing the skill of experts is critical. AE is known to be closely related to material removal rate(MRR). As the surface is rougher, MRR gets larger and AE increased. The surface roughness can be indirectly estimated using the AE signal measured during automatic die polishing process. In this study, The polishing state monitoring system using AEms signal was developed. This system can be not only to monitor the abnormal state but also to estimate a state of surface roughness of polishing surface qualitatively.

• Membrane and Water Treatment
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• 제6권5호
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• pp.365-378
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• 2015

Herein, the preparation of anion exchange membrane (AEM) from brominated poly(2,6-dimethyl 1,6-phenylene oxide) BPPO and dimethylaniline (DMA) by phase-inversion process is reported. Anion exchange membranes (AEMs) are prepared by varying the DMA contents. Prepared AEMs show high thermal stability, water uptake (WR) around 202% to 226%, dimensional change ratios of 1.5% to 2.6% and ion exchange capacities (IECs) of 0.34 mmol/g to 0.82 mmol/g with contact angle of $59.18^{\circ}$ to $65.15^{\circ}$. These membranes are porous in nature as confirmed by SEM observation. The porous property of membranes are important as it could reduce the resistance of transportation of ions across the membranes. They have been used in diffusion dialysis (DD) process for recovery of hydrochloric acid (HCl) from the mixture of HCl and ferrous chloride ($FeCl_2$). Presence of $-N+(CH_3)_2C_6H_5Br^-$ as a functional group in membrane matrix facilitates its applications in DD process. The dialysis coefficients of hydrochloric acid ($U_H$) of the membranes are in range of 0.0016 m/h to 0.14 m/h and the separation factors (S) are in range of 2.09 to 7.32 in the $HCl/FeCl_2$ system at room temperature. The porous membrane structure and presence of amine functional group are responsible for the mechanism of diffusion dialysis (DD).

• 멤브레인
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• 제34권2호
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• pp.154-162
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• 2024

음이온 교환막은 수전해 시스템에서 매우 중요한 역할을 하며, 생성된 수소와 산소 기체를 물리적으로 분리할 뿐만 아니라 전극 사이에서 수산화 이온의 선택적인 전달을 용이하게 한다. 음이온 교환막에 요구되는 특성은 수산화 이온에 대한 높은 전도도와 알칼리 환경에서의 화학적/기계적 안정성 등이 있다. 본 연구에서는 셀룰로오스 나노 크리스탈이 포함된 poly(terphenyl piperidinium) (qPTP/CNC) 복합매질분리막을 제조하였다. 고분자 매질로 사용된 poly(terphenyl piperidinium)은 super-acid 중합법을 통해 제조되었으며 이온전도성과 알칼라인 내구성이 뛰어난 소재로 알려져 있다. qPTP/CNC 분리막의 구조는 고분자와 나노 입자 계면의 공극이나 큰 응집체가 없는 조밀하고 균일한 형태를 나타냈다. CNC 나노 입자가 2wt% 첨가된 qPTP/CNC 분리막은 높은 이온교환용량(1.90 mmol/g)과 낮은 함수율(9.09%) 및 팽윤도(5.56%)를 보였다. 또한, 복합막은 수전해 작동 환경인 50℃ 1 M KOH에서 상용 FAA-3-50 분리막에 비해 월등히 낮은 저항과 우수한 알칼라인 내구성(384시간)을 달성했다. 이러한 결과는 친수성 첨가제인 CNC가 음이온 교환막의 이온 전도 특성과 알칼라인 내구성 향상에 기여할 수 있음을 보고하였다.

• 한국수소및신에너지학회논문집
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• 제29권5호
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• pp.458-465
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• 2018

This study reports the fabrication of anion exchange membranes (AEMs) containing two kinds of functional groups: i) trimethylphosphite (TMP) and ii) trimethylamine (TMA). We carried out the synthesis of polymers to enhance thermal stability and ion conductivity. The alternative polymer was prepared using 2,2-bis(4-hydroxy-3-methylphenyl)propane and decafluorobiphenyl. The membrane was fabricated by solution casting method. The thermal stability of membranes was examined by TGA. The physiochemical properties of membranes were also investigated in terms of water uptake, swelling ratio, ion exchange capacity, and ion conductivity. The hydroxide ion conductivity of the membranes reached about 20.2 mS/cm for quaternary ammonium poly(arylene ether) (QA-PAE) containing TMA moiety and 5.1 mS/cm for quaternary phosphonium PAE (QP-PAE) containing TMP moiety at $90^{\circ}C$.