• Title/Summary/Keyword: Key green technology

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High Performance Computing: Infrastructure, Application, and Operation

  • Park, Byung-Hoon;Kim, Youngjae;Kim, Byoung-Do;Hong, Taeyoung;Kim, Sungjun;Lee, John K.
    • Journal of Computing Science and Engineering
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    • v.6 no.4
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    • pp.280-286
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    • 2012
  • The last decades have witnessed an increasingly indispensible role of high performance computing (HPC) in science, business and financial sectors, as well as military and national security areas. To introduce key aspects of HPC to a broader community, an HPC session was organized for the first time ever for the United States and Korea Conference (UKC) during 2012. This paper summarizes four invited talks that each covers scientific HPC applications, large-scale parallel file systems, administration/maintenance of supercomputers, and green technology towards building power efficient supercomputers of the next generation.

Bubble breakup dynamics and flow behaviors of a surface-functionalized nanocellulose based nanofluid stabilized foam in constricted microfluidic devices

  • Wei, Bing;Wang, Yuanyuan;Wen, Yangbing;Xu, Xingguang;Wood, Colin;Sun, Lin
    • Journal of Industrial and Engineering Chemistry
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    • v.68
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    • pp.24-32
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    • 2018
  • Nanocellulose was surface-functionalized toward the applications in enhanced oil recovery (EOR) as a green alternative. The focus of this paper is on the effect of this material based nanofluid (NF) on foam lamella stabilization through studying its bubble breakup dynamics and flow behaviors in constricted mircofluidic devices. The NF stabilized foam produced an improved flow resistance across the capillary largely due to the capillary trapped bubbles at the contraction. The "snap-off" caused the NF stabilized foam to produce finer textured bubbles, which can migrate readily forward to the deep porous media, as revealed by the pressure profiles.

Brewing Rutin-Enriched Lager Beer with Buckwheat Malt as Adjuncts

  • Deng, Yang;Lim, Juho;Lee, Gang-Hee;Nguyen, Thi Thanh Hanh;Xiao, Yang;Piao, Meizi;Kim, Doman
    • Journal of Microbiology and Biotechnology
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    • v.29 no.6
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    • pp.877-886
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    • 2019
  • Brewing with buckwheat as an ingredient has been proven to be successful in several previous studies. However, few studies have focused on the effects of buckwheat on the rutin content and antioxidant activity of beer. In order to develop a lager beer with high rutin content and desirable sensory characteristics, tartary buckwheat malt was used as a brewing adjunct. The results showed that the rutin-degrading enzyme was the key factor affecting the rutin content in the wort and beer. Compared to beer made using the common mashing method, the rutin content in the buckwheat beers produced using an improved mashing method was approximately 60 times higher. The total flavonoid contents in buckwheat beers also depended strongly on the mashing methods, ranging from 530.75 to 1,704.68 mg QE/l. The rutin-rich beers also showed better oxidative stability during forced-aging. Meanwhile, the buckwheat beers were found to be acceptable in terms of the main quality attributes, flavor, and taste.

Synthesis of Polyamine Grafted Chitosan Copolymer and Evaluation of Its Corrosion Inhibition Performance

  • Li, Heping;Li, Hui;Liu, Yi;Huang, Xiaohua
    • Journal of the Korean Chemical Society
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    • v.59 no.2
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    • pp.142-147
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    • 2015
  • Two new chitosan derivatives, polyamine grafted chitosan copolymers have been synthesized for corrosion protection of carbon steel in acidic medium. First, methyl acrylate graft chitosan copolymer (CS-MAA) was prepared by the reaction of chitosan (CS) and methyl acrylate (MAA) via the Michael addition reaction. Then, CS-MAA was reacted with ethylene diamine (EN) and triethylene tetramine (TN) respectively to synthesize ethylene diamine grafted chitosan copolymer (CS-MAA-EN) and triethylene tetramine grafted chitosan copolymer (CS-MAA-TN), and the structures were characterized by Fourier-transform infrared spectroscopy (FT-IR). At last, the corrosion inhibition activities on Q235 carbon steel were investigated by using gravimetric measurements, metallographic microscope, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The compounds CS-MAA-EN and CS-MAA-TN show an appreciable corrosion inhibition property against corrosion of Q235 carbon steel in 5% HCl solution at $25^{\circ}C$. It has been observed that CS-MAA-EN shows greater corrosion inhibition efficiency than CS-MAA-TN. The inhibition efficiency of CS-MAA-EN was close to 90% when the mass fraction concentration was 0.2%~0.3%; the inhibition efficiency of CS-MAA-TN was close to 85% when the mass fraction concentration was 0.02%. The present work provided very promising results in the preparation of green corrosion inhibitors.

A Study on the Installation Method of PRB by Controlling Groundwater Flow in Hybrid Funnel and Gate (하이브리드 Funnel and Gate 지하수 흐름제어를 통한 반응벽체 설치 연구)

  • Tae Yeong Kim;Jeong Yong Cheon;Myeong Jae Yi;Yong Hoon Cha;Seon Ho Shin;Meong Do Jang;Jeongwoo Kim
    • Journal of Soil and Groundwater Environment
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    • v.28 no.3
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    • pp.1-11
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    • 2023
  • Permeable reactive barrier (PRB) is a prominent in-situ remedial option for cleanup of contaminated groundwater and has been gaining increasing popularity in recent years. Funnel-and-gate systems, comprised of two side wings of impermeable walls and a central gate wall, are frequently implemented in many sites, but often suffers from bypassing of groundwater due to the progressive clogging of the gate wall over extended period of time. This study investigated technical feasibility of a hybrid funnel-and-gate system designed to address the flow deterioration in the gate wall. The key attribute of the proposed hybrid system is the operation of drainage units at the barrier walls and rear end of the gate wall. A conceptual modeling with MODFLOW indicated the groundwater inside the barrier was maintained at appropriate level to be guided toward the gate wall, yielding constant discharging of groundwater from the gate.

Spatial Analysis on Mismatch Between Particulate Matter Regulation Services Supply and Demand in Urban Area - A Case Study of Suwon - (도시녹지 미세먼지 조절 서비스 수요와 공급의 공간적 차이 분석 - 수원시를 대상으로 -)

  • Kang, Da-In;Kwon, Hyuk-Soo;Choi, Tae-Young;Park, Chan;Kim, Sung-Hoon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.24 no.2
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    • pp.57-69
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    • 2021
  • Urban green spaces supply ecosystem services (ESs), which are consumed by city residents and generate demand, to improve air quality. It is important to determine supply and demand for ESs and reduce the gap for efficient management. This study proposed a method to use the concept of supply and demand for ESs in the decision-making process for urban planning or management. PM10 concentrations were converted to weight for demand assessment on PM10 reduction, and PM10 absorption capacity of all green spaces including the forests, and that of urban green spaces excluding forests, was calculated for each supply assessment. The differences in the calculated supply and demand were analyzed to derive the mismatched regions in Suwon. As a result, regions with big forested areas showed sufficient supply, indicating that the degree of mismatch among administrative neighborhoods (dong) varied greatly depending on whether they had a forest. An analysis of only urban green spaces showed that all neighborhoods lacked supply. Forests with high PM10 absorption capacity had a great effect, but urban green spaces can be considered a key element in reducing PM10 in daily life. Considering the mismatch of supply and demand, spatial distribution, and population distribution, it is possible to prioritize the supply of urban green spaces to reduce PM10 and, furthermore, support decision making for priority zones subject to forest conservation and designation and cancellation of green spaces, which gives significance to this study.