• Title, Summary, Keyword: CFL

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ACCURACY AND CONVERGENCE OF THE LOCAL PRECONDITIONING ON THE HIGH ASPECT RATIO GRIDS (가로세로비가 큰 격자에서 국소 예조건화 기법의 정확성 및 수렴성)

  • Lee, J.E.;Kim, Y.;Kwon, J.H.
    • 한국전산유체공학회:학술대회논문집
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    • pp.269-276
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    • 2009
  • The local preconditioning method has both robust convergence and accurate solutions by using local flow properties for parameters in the preconditioning matrix. Preconditioning methods have been very effective to low speed inviscid flows. In the viscous and turbulent flows, deterioration of convergence should be overcame on the high aspect ratio grids to get better convergence and accuracy. In the present study, the local time stepping and min-CFL/max-VNN definitions are applied to compare the results and we propose the method that switches between two methods. The min-CFL definition is applied for inviscid flow problems and the min-CFL/max-VNN definition is implemented to viscous and turbulent flow problems.

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Flexural Rehabilitation Performance of Reinforced Concrete Beams Strengthened with Carbon Fiber Laminate (탄소섬유판을 이용한 철근콘크리트 보의 휨 보강 성능)

  • Chung, Lan;Kim, Sung-Chul;Lee, Hee-Kyoung;Yoo, Seong-Hoon;Kim, Joong-Koo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.3 no.1
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    • pp.121-128
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    • 1999
  • In this study, the behavior of R/C beams strengthened with carbon fiber laminate (CFL) is analyzed from the test results. CFL is attractive for this application due to its good tensile strength and low weight. Test parameters are the width and the thickness of CFL and repair of damaged specimen. The failure mode and ultimate load are analyzed from these measured data. Test results show that the peak load of specimens strengthened with CFL is increased to 1.27~2.04 times that of non-rehabilitation specimen. The wider lap width, larger amount of CFL, the larger strength is obtained. But the ductile behavior of the rehabilitated specimens is inversely proportional to the CFL thickness.

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Design and Implementation of PFC and THD Reduction System for CFL Mulitple Connection (다중접속 CFL용 PFC 및 THD 감소 시스템의 설계 및 구현)

  • 박종연;조호찬;최원호
    • Proceedings of the IEEK Conference
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    • pp.67-70
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    • 2002
  • In this paper, we have researched a Automatic Power Factor Correction and THD reduction System for the multiple connection of CFL. Also in this paper, the power factor has been researched for the design of CFL, found the reason why the power factor is low and THD is too high. This paper has designed the PFC System for the multiple connection of CFL, and then we have increased the power factor and reduced the total harmonic distortion, by implementing them.

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Characteristics of Mercury Concentration in Vapor Phase from Compact Fluorescent Lamp (소형형광등(Compact Fluorescent Lamp)의 파쇄에 따른 기상에서의 수은농도 특성)

  • Rhee, Seung-Whee
    • Korean Chemical Engineering Research
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    • v.52 no.5
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    • pp.652-656
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    • 2014
  • Mercury amount in vapor phase from 3 types of CFL(compact fluorescent lamp) are estimated by measuring mercury concentration in vapor phase. The mercury concentration in vapor phase from CFL is sharply decreased during initial time and then the change in the mercury concentration is slightly decreased up to 24 hours. The mercury concentration in vapor phase is almost constant after 42 hours, which can be called by stabilized concentration. It can be estimated that the stabilized concentration is caused by the evaporation of mercury in the residues of broken CFL and can be affected by temperature and pressure in crushing apparatus. The mercury concentration for CFL manufactures are in the order of A < B < C as the same results of the initial mercury concentration and the stabilized concentration in vapor phase. As increased air flow rate, the partial pressure of mercury is decreased and the amount of mercury is reduced. Initially, the mercury concentration in vapor phase emitted from CFLs is higher than the regulatory level of $0.1mg/m^3$ in the specific facilities regardless of air flow rate. Hence, it is absolutely necessary that mercury in vapor phase should be controlled at the point of crushing campact fluorescent lamp.

Design of CFL Linearisation Chip for the Mobile Radio Using Ultra-Narrowband Digital Modulation (디지털 초협대역 단말기용 CFL 선형화 칩 설계)

  • Chong Young-Jun;Kang Min-Soo;Yoo Sung-Jin;Chung Tae-Jin;Oh Seung-Hyeub
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.16 no.7
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    • pp.671-680
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    • 2005
  • The CFL linearisation chip which is one of key devices in ultra-narrowband mobile radio transmitter using CQPSK digital modulation method is designed and implemented with $0.35{\mu}m$ CMOS technology. The reduced size and low cost of transmitter are available by the use of direct-conversion and CFL ASIC chip, which improve the power effi챠ency and linearity of transmitting path. In addition, low power operation is possible through CMOS technology The performance test results of transmitter show -25 dBc improvement of IMD level at the 3 kHz frequency offset and then satisfy FCC 47 CFR 90.210 E emission mask in the operation of CFL ASIC chip. At that time, the transmitting power is about PEP(Peak-to-Envelope Power) 5 W. The main parameters to improve the transmitting characteristic and to compensate the distortion in feed back loop such as DC-offset, loop gain and phase value are interfaced with notebook PC to be controlled with S/W.

Flowering and Morphological Responses of Petunia and Pansy as Influenced by Lamp Type and Lighting Period to Provide Long Days (장일처리 광원의 종류 및 광조사 시간에 따른 페튜니아와 팬지의 개화 및 형태학적 반응)

  • Oh, Wook;Runkle, Erik S.
    • Horticultural Science & Technology
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    • v.34 no.2
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    • pp.207-219
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    • 2016
  • Incandescent (INC) lamps have been commonly used to promote flowering of long-day (LD) plants during short-day (SD) seasons, but production of INC lamps has been prohibited due to their low energy efficiency. One of the light sources replacing INC lamps is a compact fluorescent lamp (CFL). This study was carried out to compare the flowering and morphological responses of LD annuals grown in a controlled environment greenhouse at $20^{\circ}C$ with a truncated 9-h SD and a 2- or 4-h night interruption (NI) or 6-h day extension (DE) provided by lighting from INC lamps, CFLs, or a combination of the two (INC + CFLs), in which red (R) to far-red (FR) ratios were 0.60, 8.46, and 0.91, respectively, and their PPFDs were $2.3{\pm}0.3{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. After 12 weeks of treatment, $Petunia{\times}hybrida$ 'Wave Purple' plants did not flower under the SD photoperiod whereas 100% flowered under all of the LD treatments. Flowering was more rapid under the INC or INC + CFL lighting treatments compared to CFL and DE, and 4-h NI enhanced flowering compared to 2-h NI. In addition, plants under DE and 4h-NI generally flowered earlier than under 2-h NI. All petunia 'Single Dreams Red' plants flowered within 65 days after treatment, and flowering was hastened by some LD lighting regimens and lamp types. Plants under DE and 4h-NI generally flowered earlier than under 2-h NI INC or INC + CFL compared to FL, and flowering time under INC 6-h DE was earliest. In addition, INC lighting promoted stem elongation of both petunia cultivars. In both pansy (Viola${\times}wittrockiana$) 'Coiossus Yellow' and 'Delta Blue Blotch', LD treatments, especially using INC lamps, promoted flowering whereas the lighting period had little influence on days to flowering. Therefore, INC or INC + CFL with lower R:FR promoted flowering and stem extension and the promoting effect was larger with longer lighting periods. These results suggest that CFLs can be used to provide LDs to promote the flowering of petunia and pansy and to reduce stem elongation, although the promoting effect on flowering is sometimes less than that of INC lamps alone.

Precise control flow protection based on source code (소스코드 기반의 정밀도 높은 실행 흐름 보호 기법)

  • Lee, JongHyup;Kim, Yong Seung
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.22 no.5
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    • pp.1159-1168
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    • 2012
  • Control Flow Integrity(CFI) and Control Flow Locking(CFL) prevent unintended execution of software and provide integrity in control flow. Attackers, however, can still hijack program controls since CFI and CFL does not support fine-granularity, context-sensitive protection. In this paper, we propose a new CFI scheme, Source-code CFI(SCFI), to overcome the problems. SCFI provides context-sensitive locking for control flow. Thus, the proposed approach protects software against the attacks on the previous CFI and CFL schemes and improves safety.

A novel F-box protein with leucine-rich repeats affects defecation frequency and daumone response in Caenorhabditis elegans

  • Kim, Sung-Moon;Jang, Sang-Ho;Son, Na-Rae;Han, Ching-Tack;Min, Kwan-Sik;Lee, Hak-Kyo;Hwang, Sue-Yun
    • Animal cells and systems
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    • v.16 no.4
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    • pp.280-288
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    • 2012
  • Targeted degradation of proteins through ubiquitin-mediated proteolysis is an important control mechanism in various cellular processes. The process of ubiquitin conjugation is achieved by three enzyme complexes, among which the ubiquitin ligase complex (E3) is in charge of substrate specificity. The SCF (SKP1-CUL1-F-box) family portrays the largest and the most characterized member of the E3 ligases. For each SCF complex, the ubiquitination target is recognized by the F-box protein subunit, which interacts with the substrate through a unique C-terminal domain. We have characterized a novel F-box protein CFL-1 that represents a single LRR-type F-box (FBXL) in the Caenorhabditis elegans genome. CFL-1 is highly homologous to FBXL20 and FBXL2 of mammals, which are known to regulate synaptic vesicle release and cell cycle, respectively. A green fluorescence protein (GFP)-reporter gene fused to the cfl-1 promoter showed restricted expression around the amphid and the anus. Modulation of CFL-1 activity by RNAi affected the time interval between defecations. RNAi-treated worms also exhibited reduced tendency to form dauer when exposed to daumone. The potential involvement of CFL-1 in the control of defecation and pheromone response adds to the ever expanding list of cellular processes controlled by ubiquitin-mediated proteolysis in C. elegans. We suggest that CFL-1, as a single LRR-type F-box protein in C. elegans, may portray a prototype gene exerting diverse functions that are allocated among multiple FBXLs in higher organisms.

Indications of Lateral Ankle Ligament Reconstruction with a Free Tendon and Associated Evidence (유리건을 이용한 족관절 외측 인대 재건술의 적응증과 근거)

  • Kang, Hwa-Jun;Jung, Hong-Geun
    • Journal of Korean Foot and Ankle Society
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    • v.22 no.3
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    • pp.91-94
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    • 2018
  • Ankle sprain is one of the most common musculoskeletal injuries. Although most ankle sprains respond well to conservative measures, chronic instability following an acute sprain has been reported to occur in 20% to 40% of patients. Some individuals are eventually indicated for a lateral ankle ligament reconstruction due to persistent ankle instability. More than 80 surgical procedures have been described to address lateral ankle stability. These range from direct repair of the anterior talofibular ligament (ATFL) and of the calcaneofibular ligament (CFL) to reconstructions based on the use of autograft or allograft tissues. However, the best surgical option remains debatable. The modified $Brostr{\ddot{o}}m$ procedure is most widely used for direct ligament repair, but not always possible because of the poor ATFL or CFL quality or deficiency of these ligaments, which prevents effective shortening imbrication. Furthermore, the importance of a CFL reconstruction has been emphasized recently. On the other hand, it is difficult to achieve an efficient CFL reconstruction during the $Brostr{\ddot{o}}m$ procedure. Others have reported that an anatomic reconstruction of injured ligaments restores the normal resistance to anterior translation and inversion without restricting subtalar or ankle motion, and as a result, anatomic reconstructions for lateral ankle instability utilizing an autograft or allograft tendon have gained popularity.

Confined Effect of Concrete Compressive Members Strengthened with Carbon Fiber Laminate (탄소섬유판으로 횡보강된 콘크리트 압축부재의 보강성능)

  • Chung, Lan;Lee, Hee-Kyoung;Kim, Sung-Chul;Yoo, Seong-Hoon;Kim, Joong-Koo
    • Magazine of the Korea Concrete Institute
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    • v.10 no.6
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    • pp.345-352
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    • 1998
  • Compressive strength of concrete compression members strengthend with carbon fiber laminate(CFL) were studied from the test results. Test parameters are spacing, thickness, width, ply and spliced length of carbon fiber laminates. Specimens strength with sheets failed with sudden tensile rupture of the laminate, which indicate very brittle failure mode. Test result shows that closer spacing and to increas thickness of CFL is more effective. But strengthening ratio with 1-ply CFL is more effective than that of specimen with 2-ply CFL. Compressive strength capacity of specimen splied 24cm shows almost similar strength to that of non-spliced specimen. The ultimate load carrying of specimen strengthened with CFL ranges 1.11~1.86 times of that of non-strengthened specimen.