• 제목/요약/키워드: energy and environment

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Environment Dose of Kumsan area in Okchun Meatmorphic Belt

  • Choi, Geun-Sik;Kang, Mun-Ja;Cho, Young-Hyun;Chung, Kun-Ho;Lee, Wan-No;Kim, Hee-Reyoung;Cha, Hyun-Ju;Park, Doo-Won;Choi, Sang-Do;Lee, Chang-Woo;Choi, Soo-Yong
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 2005년도 춘계학술발표회
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    • pp.970-971
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    • 2005
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Characteristics of Ozonizers Manufactured in Energy & Environment Electromagnetic Lab. of Yeungnam University

  • Song, Hyun-Jig;Kim, Ki-Chai;Park, Won-Zoo;Lee, Kwang-Sik;Lee, Dong-In
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 1999년도 학술대회논문집-국제 전기방전 및 플라즈마 심포지엄 Proceedings of 1999 KIIEE Annual Conference-International Symposium of Electrical Discharge and Plasma
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    • pp.11-16
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    • 1999
  • Discharge characteristics research for high voltage and large current electric machinery design, the development of ozonizer with high yield and efficiency for environment improvement, generation of plasma & laser and EMI EMC are research fields of Enersy & Environment Electromagnetic Laboratory(EEEL) in the school of electrical & electronic engineering of Yeungnam University. On this paper, we would like to introduce the discharge and ozone generation characteristics of ozonizers designed and manufactured by EEEL. After starting research for fluid gas discharge characteristics early in the 1980's, high voltage nozzle(HVN) type ozonizer, neon lamp(Nelamp) type ozonizer, ozone lamp(Olamp) type ozonizer and multi-discharge type ozonizer(MDO) have been investigated since 1990.

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Improved structures of stainless steel current collector increase power generation of microbial fuel cells by decreasing cathodic charge transfer impedance

  • Nam, Taehui;Son, Sunghoon;Kim, Eojn;Tran, Huong Viet Hoa;Koo, Bonyoung;Chai, Hyungwon;Kim, Junhyuk;Pandit, Soumya;Gurung, Anup;Oh, Sang-Eun;Kim, Eun Jung;Choi, Yonghoon;Jung, Sokhee P.
    • Environmental Engineering Research
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    • 제23권4호
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    • pp.383-389
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    • 2018
  • Microbial fuel cell (MFC) is an innovative environmental and energy system that converts organic wastewater into electrical energy. For practical implementation of MFC as a wastewater treatment process, a number of limitations need to be overcome. Improving cathodic performance is one of major challenges, and introduction of a current collector can be an easy and practical solution. In this study, three types of current collectors made of stainless steel (SS) were tested in a single-chamber cubic MFC. The three current collectors had different contact areas to the cathode (P $1.0cm^2$; PC $4.3cm^2$; PM $6.5cm^2$) and increasing the contacting area enhanced the power and current generations and coulombic and energy recoveries by mainly decreasing cathodic charge transfer impedance. Application of the SS mesh to the cathode (PM) improved maximum power density, optimum current density and maximum current density by 8.8%, 3.6% and 6.7%, respectively, comparing with P of no SS mesh. The SS mesh decreased cathodic polarization resistance by up to 16%, and cathodic charge transfer impedance by up to 39%, possibly because the SS mesh enhanced electron transport and oxygen reduction reaction. However, application of the SS mesh had little effect on ohmic impedance.

Operational Characteristics of High-Performance kW class Alkaline Electrolyzer Stack for Green Hydrogen Production

  • Choi, Baeck B.;Jo, Jae Hyeon;Lee, Taehee;Jeon, Sang-Yun;Kim, Jungsuk;Yoo, Young-Sung
    • Journal of Electrochemical Science and Technology
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    • 제12권3호
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    • pp.302-307
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    • 2021
  • Polymer electrolyte membrane (PEM) electrolyzer or alkaline electrolyzer is required to produce green hydrogen using renewable energy such as wind and/or solar power. PEM and alkaline electrolyzer differ in many ways, instantly basic materials, system configuration, and operation characteristics are different. Building an optimal water hydrolysis system by closely grasping the characteristics of each type of electrolyzer is of great help in building a safe hydrogen ecosystem as well as the efficiency of green hydrogen production. In this study, the basic operation characteristics of a kW class alkaline water electrolyzer we developed, and water electrolysis efficiency are described. Finally, a brief overview of the characteristics of PEM and alkaline electrolyzer for large-capacity green hydrogen production system will be outlined.

창호 리트로피트를 통한 에너지 절감 및 실내 열환경 개선 효과 분석에 관한 연구 (Energy Saving Effect and Improvement of Indoor Thermal Environment through the Window Retrofit)

  • 정진우;주정훈;조동우
    • 한국태양에너지학회 논문집
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    • 제38권3호
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    • pp.29-36
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    • 2018
  • The goal of this study is to retrofit the windows of residential buildings and to activate the green remodeling by verifying energy saving and indoor thermal environment. As a result of analysis of the energy saving effect of 458 units window retrofits, it was possible to reduce the energy requirement by 48.20% ~ 54.97%. According to the improvement on indoor environment, it was possible to operate by reducing heating temperature and supply time. The actual gas consumption of the heating period was reduced by 25% compared with that of the window retarder to save 28,968 thousand won of heating energy cost. Resident's satisfaction surveys were conducted one year after window retrofit. More than 80% of the respondents answered that they satisfied the improvement on window performance, indoor thermal environment and indoor sound environment. As a result, we verified the energy saving effect and the improvement on the indoor environment through window retrofits.

방사선을 이용하여 제조한 zinc oxide 입자 함유 poly(acrylic acid) 하이드로젤의 특성 (Characterization of Poly(acrylic acid) Hydrogel Containing Zinc Oxide Particle Prepared by Radiation)

  • 박종석;정성린;신영민;최종배;권희정;임윤묵;전준표;김현빈;오승환;강필현;노영창
    • 방사선산업학회지
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    • 제6권2호
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    • pp.153-158
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    • 2012
  • In this research, poly(acrylic acid) (PAAc) hydrogels containing zinc oxide particle were prepared by gamma-ray irradiation. PAAc powder was completely dissolved in distilled water at room temperature. Water-insoluble zinc oxide powder were added into the PAAc solution and stirred until totally dissolved. Finally, the mixture was irradiated by gamma-ray irradiation to make crosslinking. The effects of various parameters such as zinc ions' concentration, irradiation doses were varied and investigated in detail. PAAc hydrogels containing zinc oxide particle were characterized by gel content and swelling ratio. Moreover, the antibacterial properties of this material were evaluated by paper diffusion test against the Gram positive and Gram negative bacteria.