• 제목/요약/키워드: Cycle net

검색결과 485건 처리시간 0.024초

Two new relationships for slip velocity and characteristic velocity in a non-center rotating column

  • Torkaman, Rezvan;Heydari, Mehran;Cheshmeh, Javad Najafi;Heydari, Ali;Asadollahzadeh, Mehdi
    • Nuclear Engineering and Technology
    • /
    • 제54권8호
    • /
    • pp.2809-2818
    • /
    • 2022
  • In this investigation work, liquid-liquid extraction (L.L.E) through three distinctive frameworks have been examined for assurance of slip velocity (S.V), and characteristic velocity (C.V) in a non-center rotating column (N.C.R.C) with a wide extend of factors. Three double frameworks with distinctive interfacial tension comprising of toluene-water (high interfacial tension), n-butyl acetate-water (medium interfacial tension), and n-butanol-water (low interfacial tension) were investigated for tests. Two common relationships for the expectation of S.V and C.V, including phase stream rates, rotor speed, column geometry additionally physical properties, are displayed. The recommended relationships were compared with test information gotten from the writing and the display examination. Findings of this study, the present proposed correlations are more accurate than those previously reported.

열원온도와 작동유체에 따른 초월임계 유기랭킨사이클의 열역학적 성능 특성 (Thermodynamic Performance Characteristics of Transcritical Organic Rankine Cycle Depending on Source Temperature and Working Fluid)

  • 김경훈
    • 대한기계학회논문집B
    • /
    • 제41권11호
    • /
    • pp.699-707
    • /
    • 2017
  • 본 연구에서는 아홉 종류의 작동유체를 고려하여 저온 열원으로 구동되는 아임계 및 초월임계 유기 랭킨 사이클의 열역학적 성능 특성을 비교 해석한다. 터빈입구압력, 열원온도 및 작동유체가 열교환기 내 온도분포와 핀치포인트, 작동유체의 유량, 시스템 출력 및 열효율 등 시스템의 성능에 미치는 영향을 분석한다. 해석 결과는 작동유체의 압력이 아임계 영역에서 초임계 영역으로 높아지면 열교환기에서 열원과 작동유체 사이의 온도 불균일 정도가 감소하면서 시스템 출력이나 열효율 등은 증가하나 시스템의 단위출력당 터빈 크기는 작아짐을 보여준다.

탄성 튜브가 연결된 펌핑 챔버를 이용한 무밸브 펌프의 수치해석 (Simulation of Valveless Pump Using Pumping Chamber Connected to Elastic Tube)

  • 신수재;장정봉;성형진
    • 대한기계학회논문집B
    • /
    • 제37권2호
    • /
    • pp.111-117
    • /
    • 2013
  • 탄성튜브가 연결된 펌핑 챔버를 이용한 무밸브 펌프를 가상경계방법을 이용하여 수치적으로 연구하였다. 탄성 튜브와 펌핑 챔버 사이의 상호작용으로 인하여 무밸브 펌프 내의 유동이 생성되었으며, 탄성튜브의 스트레칭 계수, 벤딩 계수, 종횡비가 무밸브 펌프의 전체 유량에 미치는 영향을 살펴보았다. 펌프의 메커니즘을 이해하고자, 시간에 따른 탄성 튜브의 움직임과 그에 따른 유동 속도의 변화를 자세히 살펴보았으며, 탄성 튜브의 직경 크기와 펌프의 평균 유량 사이의 관계를 분석하였다.

40 Gbps RZ Transmission Using Dispersion Compensation of Single-Span in Optical Transmission Links with Multi-Span of Single Mode Fiber

  • Lee, Seong-Real
    • Journal of information and communication convergence engineering
    • /
    • 제9권1호
    • /
    • pp.32-37
    • /
    • 2011
  • In dispersion management (DM) and optical phase conjugation applied into optical transmission links with multi fiber spans for minimizing the impact of nonlinearity and group velocity (GVD), implementation possibility of DM using only one fiber span for pre- or postcompensation was assessed as a function of duty cycle of RZ pulse and residual dispersion per span (RDPS). It is confirmed that DM with optimal net residual dispersion (NRD) controlled by only one fiber span could be sufficiently applied into optical transmission links, though optimal NRD is more increased than that in transmission links with the general DM scheme of pre- and postcompensation. Thus, it is expected that optical transmission system is simply designed and implemented by applying the proposed DM scheme into real optical transmission links. Also, it is confirmed that the advantageous duty cycle of RZ is 0.5 and RDPS is setting to be small value for the effective transmitting wide signal wavelength range in optical links with optimal NRD controlled by only one fiber span.

PLC 기반 제어정보 모델링 방법론 (Control Level Process Modeling Methodology Based on PLC)

  • 고민석;곽종근;왕지남;박상철
    • 한국시뮬레이션학회논문지
    • /
    • 제18권4호
    • /
    • pp.67-79
    • /
    • 2009
  • 자동차 제조 기업은 생산되는 제품 수명 주기가 짧기 때문에, 공정계획 및 라인 변경이 빈번히 일어난다. 따라서 새로운 공정을 계획하는 경우보다 기존 공정계획을 바탕으로 라인의 설비를 재배치하거나, 제어정보를 수정하는 경우가 많다. 하지만 생산라인의 제어 정보를 기술하는 표준 방법론이 없기 때문에 기존 공정의 정보를 해석하고 수정하는데 많은 노력이 요구된다. 따라서 본 논문에서는 자동화 생산라인에서 일반적으로 사용할 수 있는 제어레벨 공정 모델링 방법론(SOS-Net)을 제안하고자 한다. 제안된 방법론은 실제 현장라인과 동일한 Low Level의 정보들을 체계적으로 표현함으로써 모델링 결과가 현업에 직접 사용될 수 있도록 고려하였다. 본 논문에서 제안하는 SOS-Net은 쉽게 작성할 수 있으며, 기존의 High Level 모델링 방법들이 갖는 한계점을 극복하고, 현업에서 사용할 수 있는 FB(Function Block) 제어 코드를 생성하는 것을 목적으로 한다.

Effects of Ozone on $CO_2$ Assimilation and PSII Function in Two Tobacco Cultivars with Different Sensitivities

  • Yun, Myoung-Hui
    • Journal of Korean Society for Atmospheric Environment
    • /
    • 제22권E2호
    • /
    • pp.89-98
    • /
    • 2006
  • Two tobacco cultivars (Nicotiana tabacum L.), Bel-B and Bel-W3, tolerant and sensitive to ozone, respectively, were grown in a greenhouse supplied with charcoal filtered air and exposed to 200 ppb ozone for 4 hr. Effects on chlorophyll fluorescence, net photosynthesis, and stomatal conductance are described. Quantum yield was calculated from chlorophyll fluorescence and the initial slope of the assimilation-light curve measured by the gas exchange method. Only the sensitive cultivar, Bel-W3, developed visual injury symptoms on up to 50% of the $5^{th}$ leaf. The maximum net photosynthetic rate of ozone-treated plants was reduced 40% compared to control plants immediately after ozone fumigation in the tolerant cultivar; however, photosynthesis recovered by 24 hr post fumigation and remained at the same level as control plants. On the other hand, ozone exposure reduced maximum net photosynthesis up to 50%, with no recovery, in the sensitive cultivar apparently causing permanent damage to the photosystem. Reductions in apparent quantum efficiency, calculated from the assimilation-light curve, differed between cultivars. Bel-B showed an immediate depression of 14% compared to controls, whereas, Bel-W3 showed a 27% decline. Electron transport rate (ETR), at saturating light intensity, decreased 58% and 80% immediately after ozone treatment in Bel-B and Bel-W3, respectively. Quantum yield decreased 28% and 36% in Bel-B and Bel-W3, respectively. It can be concluded that ozone caused a greater relative decrease in linear electron transport than maximum net photosynthesis, suggesting greater damage to PSII than the carbon reduction cycle.

Idaho national laboratory to demonstrate collaboration first versus competition to accelerate achieving a secure clean energy future by 2031

  • Jhansi Kandasamy;Elizabeth Brunner
    • Nuclear Engineering and Technology
    • /
    • 제56권3호
    • /
    • pp.966-972
    • /
    • 2024
  • Idaho National Laboratory (INL) announced at COP27 it would reach net zero greenhouse gas (GHG) emissions by 2031. As a Nuclear, Energy and Environment, and National Homeland Security laboratory, the predominant solution to closing the clean energy gap will include nuclear as a safe, clean, reliable and affordable electricity source with the additional benefit of producing heat and hydrogen to fuel INL's large transportation fleet. INL's collaboration first vs. competition is essential to the program's success. The focused actions in INL's Nuclear Roadmap include: Infrastructure, Licensing/Regulatory, Financial, Time to Market, Fuel Cycle and Public Confidence/Communications. The roadmap also includes nuclear technology innovations and creative partnerships with utility providers, regulators, businesses, community members, and Indigenous Peoples to accelerate deployment of advanced reactors. Through development of the Net-Zero Nuclear Roadmap, INL will offer a model to provide safe and secure energy for the nation and the world by: (1) establishing the necessary infrastructure on its 890-square mile site to support demonstration, (2) showing proven pathways through the licensing and regulation process, (3) partnering with utilities to ensure commercial application, and (4) collaborating with industry to site new technologies.

Chemical Stability of Conductive Ceramic Anodes in LiCl-Li2O Molten Salt for Electrolytic Reduction in Pyroprocessing

  • Kim, Sung-Wook;Kang, Hyun Woo;Jeon, Min Ku;Lee, Sang-Kwon;Choi, Eun-Young;Park, Wooshin;Hong, Sun-Seok;Oh, Seung-Chul;Hur, Jin-Mok
    • Nuclear Engineering and Technology
    • /
    • 제48권4호
    • /
    • pp.997-1001
    • /
    • 2016
  • Conductive ceramics are being developed to replace current Pt anodes in the electrolytic reduction of spent oxide fuels in pyroprocessing. While several conductive ceramics have shown promising electrochemical properties in small-scale experiments, their long-term stabilities have not yet been investigated. In this study, the chemical stability of conductive $La_{0.33}Sr_{0.67}MnO_3$ in $LiCl-Li_2O$ molten salt at $650^{\circ}C$ was investigated to examine its feasibility as an anode material. Dissolution of Sr at the anode surface led to structural collapse, thereby indicating that the lifetime of the $La_{0.33}Sr_{0.67}MnO_3$ anode is limited. The dissolution rate of Sr is likely to be influenced by the local environment around Sr in the perovskite framework.

LAMMER Kinase Modulates Cell Cycle by Phosphorylating the MBF Repressor, Yox1, in Schizosaccharomyces pombe

  • Kibum Park;Joo-Yeon Lim;Je-Hoon Kim;Jieun Lee;Songju Shin;Hee-Moon Park
    • Mycobiology
    • /
    • 제51권5호
    • /
    • pp.372-378
    • /
    • 2023
  • Lkh1, a LAMMER kinase homolog in the fission yeast Schizosaccharomyces pombe, acts as a negative regulator of filamentous growth and flocculation. It is also involved in the response to oxidative stress. The lkh1-deletion mutant displays slower cell growth, shorter cell size, and abnormal DNA content compared to the wild type. These phenotypes suggest that Lkh1 controls cell size and cell cycle progression. When we performed microarray analysis using the lkh1-deletion mutant, we found that only four of the up-regulated genes in the lkh1-deletion were associated with the cell cycle. Interestingly, all of these genes are regulated by the Mlu1 cell cycle box binding factor (MBF), which is a transcription complex responsible for regulating the expression of cell cycle genes during the G1/S phase. Transcription analyses of the MBF-dependent cell-cycle genes, including negative feedback regulators, confirmed the up-regulation of these genes by the deletion of lkh1. Pull-down assay confirmed the interaction between Lkh1 and Yox1, which is a negative feedback regulator of MBF. This result supports the involvement of LAMMER kinase in cell cycle regulation by modulating MBF activity. In vitro kinase assay and NetPhosK 2.0 analysis with the Yox1T40,41A mutant allele revealed that T40 and T41 residues are the phosphorylation sites mediated by Lkh1. These sites affect the G1/S cell cycle progression of fission yeast by modulating the activity of the MBF complex.

장방형 해분내의 세립 퇴적물 퇴적모형 (Modeling Sedimentation of Fine-grained Sediments in a Rectangular Basin)

  • Hyo Jin Kang
    • 한국해안해양공학회지
    • /
    • 제3권1호
    • /
    • pp.38-44
    • /
    • 1991
  • 간단한 box 모형이 장방형 해분에서의 세립 퇴적물의 퇴적현상을 설명하기 위하여 이용되었으며. 이 모형에 필요한 침식 및 퇴적률의 계수를 조사하여 남해안 가막양만에 적용하여 보았다. 해분이 외해와 연결되어 있고 외해의 부유퇴적물 농도가 일정하면 해분내에서 한 조석 주기 동안의 평균 부유퇴적물 농도는 일정한 값을 유지하게 되고 조류의 게류시 부근에는 퇴적이 일어나고 최대 유속시 부근에는 바닥 퇴적물의 재부유 및 침식이 일어나는 것을 보여주고 있다. 가막양만 처럼 퇴적이 우세한 해분에서는 조석 주기 중 퇴적이 일어나는 시간과 최대 퇴적률이 침식에 비하여 크게 나타나고 있으며, 이러한 퇴적 우세 해분의 부유퇴적물 평균농도는 외해의 부유퇴적물 농도보다 낮은 값을 보이고 있다. 또한. 조류의 유속변화에 따른 해분내기 부유퇴적물 농도변화는 고조의 약 한 시간 전에 최대값을 나타내고 저조의 약 한 시간 후에 최소값을 나타낸다.

  • PDF