• Title/Summary/Keyword: 광주과학기술원

Search Result 173, Processing Time 0.027 seconds

Tactical Service Mesh for Intelligent Traffic QoS Coordination over Future Tactical Network (미래 전술망의 지능적 트래픽 QoS 조율을 위한 전술 서비스 메쉬)

  • Kang, Moonjoong;Shin, Jun-Sik;Park, Juman;Park, Chan Yi;Kim, JongWon
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.22 no.3
    • /
    • pp.369-381
    • /
    • 2019
  • As tactical networks are gradually shifting toward IP-based flexible operation for diversified battlefield services, QoS(Quality-of-Service) coordination for service differentiation becomes essential to overcome the heterogeneous and scarce networking resources limitations. QoS coordination for tactical network traffic should be able to monitor and react the dynamic changes in underlying network topology and service priorities. In this paper, by adopting the emerging cloud-native service mesh concept into tactical network context, we study the feasibility of intelligent QoS coordination by employing tactical service mesh(TSM) as an additional layer to support enhanced traffic quality monitoring and control. The additional TSM layer can leverage distributed service-mesh proxies at tactical mesh WAN(Wide Area Network) nodes so that service-aware differentiated QoS coordination can be effectively designed and integrated with TSM-assisted traffic monitoring and control. Also, by validating the feasibility of TSM layer for QoS coordination with miniaturized experimental setup, we show the potential of the proposed approach with several approximated battlefield traffics over a simulated TSM-enabled tactical network.

The Comparison of Activation Protocols for PEMFC MEA with PtCo/C Catalyst (PtCo/C 촉매를 사용한 PEMFC MEA의 활성화 프로토콜 비교)

  • GISEONG LEE;HYEON SEUNG JUNG;JINHO HYUN;CHANHO PAK
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.34 no.2
    • /
    • pp.178-186
    • /
    • 2023
  • Three activation methods (constant voltage, current cycling, and hydrogen pumping) were applied to investigate the effects on the performance of the membrane electrode assembly (MEA) loaded with PtCo/C catalyst. The current cycling protocol took the shortest time to activate the MEA, while the performance after activation was the worst among the all activation methods. The constant voltage method took a moderate activation time and exhibited the best performance after activation. The hydrogen pumping protocol took the longest time to activate the MEA with moderate performance after activation. According to the distribution of relaxation time analysis, the improved performance after the activation mainly comes from the decrease of charge transfer resistance rather than the ionic resistance in the cathode catalyst layer, which suggests that the existence of water on the electrode is the key factor for activation.

Determination of Optimum Binder Content in the Catalyst Layer with Different GDL for Anode of HT-PEMFC (고온 고분자 전해질막 연료전지 수소극 전극에서 서로 다른 가스 확산층에 따른 최적 바인더 함량 결정)

  • CHUN, HYUNSOO;KIM, DO-HYUNG;JUNG, HYEON-SEUNG;PAK, CHANHO
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.33 no.1
    • /
    • pp.38-46
    • /
    • 2022
  • Two different gas diffusion layers having noticeable differences in micro-porous layer's (MPL's) crack were studied as a substrate for the gas diffusion electrode (GDE) with different binder/carbon (B/C) ratios in high-temperature polymer electrolyte fuel cell (Ht-PEMFC). As a result, the performance defined as the voltage at 0.2 A/cm2 and maximum power density from the single cells using GDEs from H23 C2 and SGL38 BC with different B/C ratios were compared. GDEs from H23 C2 showed a proportional increase of the voltage with the binder content on the other hand GDEs from SGL38 BC displayed a proportional decline of the voltage to the binder content. It was revealed that MPL crack influences the structure of catalyst layer in GDEs as well as affects the RCathode which is in close connection with the Ht-PEMFC performance.

Investigation on the occurrence and fate of micropollutants in domestic wastewater treatment plants based on full-scale monitoring and simple statistical analysis (현장 모니터링과 기초통계분석에 기반한 국내 하수처리장 미량오염물질 발생 및 거동 조사)

  • Chae, Sung Ho;Lim, Seung Ji;Lee, Jiho;Gashaw, Seid Mingizem;Lee, Woongbae;Choi, Sangki;Lee, Yunho;Lee, Woorim;Son, Heejong;Hong, Seok-Won
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.36 no.2
    • /
    • pp.107-119
    • /
    • 2022
  • The frequent detection and occurrence of micropollutants (MPs) in aquatic ecosystems has raised public health concerns worldwide. In this study, the behavior of 50 MPs was investigated in three different domestic wastewater treatment plants (WWTPs). Furthermore, the Kruskal-Wallis test was used to assess the geographical and seasonal variation of MPs in the WWTPs. The results showed that the concentrations of 43 MPs ranged from less than 0.1 to 237.6 ㎍ L-1, while other seven MPs including 17-ethynylestradiol, 17-estradiol, sulfathiazole, sulfamethazine, clofibric acid, simvastatin, and lovastatin were not detected in all WWTPs. Among the detected MPs, the pharmaceuticals such as metformin, acetaminophen, naproxen, and caffeine were prominent with maximum concentrations of 133.4, 237.6, 71.5, and 107.7 ㎍ L-1, respectively. Most perfluorinated compounds and nitrosamines were found at trace levels of 1.2 to 55.3 ng L-1, while the concentration of corrosion inhibitors, preservatives (parabens), and endocrine disruptors ranged from less than 0.1 to 4310.8 ng L-1. Regardless of the type of biological treatment process such as MLE, A2O, and MBR, the majority of pharmaceuticals (except lincomycin, diclofenac, iopromide, and carbamazepine), parabens (except Methyl paraben), and endocrine disruptors were removed by more than 80%. However, the removal efficiencies of certain MPs such as atrazine, DEET, perfluorinated compounds (except PFHxA), nitrosamines, and corrosion inhibitors were relatively low or their concentration even increased after treatment. The results of statistical analysis reveal that there is no significant geographical difference in the removal efficacy of MPs, but there are temporal seasonal variations in all WWTPs.

Study on Design of Heavy Payload Robot Considering Design Factor of Gravity Compensator (중력보상장치 설계계수를 고려한 고가반 로봇설계에 관한 연구)

  • Lee, Do-Seung;Lee, Ho-Su;Pyo, Sang-Hun;Yoon, Jung-Won;Lyu, Sung-Ki
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.18 no.5
    • /
    • pp.23-28
    • /
    • 2019
  • In recent years, medium- to large-scale transportation machinery and machine tool manufacturing process lines have shown a trend toward centralization, softening, lightening, and slimming to reduce costs and increase productivity. This has increased the demand for vertical articulated robots. When developing and introducing a heavy weight-handling robot that can be easily applied to existing production lines, it is expected to have a great effect in securing industrial competitiveness by solving industrial issues such as the decreased productivity and increased risk of accidents due to work involving heavy lifting. In this study, we design a 6-axis robot mechanism with a heavy load-handling capacity of 700kg or more for large-sized materials of various types supplied in small quantities.

회원사 동정 - 쓰리엘시스템, 광학렌즈 수출 확대하는 '3L-Systems'

  • 한국광학기기산업협회
    • The Optical Journal
    • /
    • s.169
    • /
    • pp.19-19
    • /
    • 2017
  • 지난해 (주)3L-Systems(대표이사 이인원) 대표이사로 취임한 이인원 박사는 표준과학연구원 광기술 연구부장, 광주과학기술원 고등 광기술연구소장, 제 14대 한국 광학회 회장을 역임한 광학분야 전문가로 2016년 대표이사 취임이후 광학렌즈 및 렌즈 모듈 수출을 확대하고 있다.

  • PDF