• Title/Summary/Keyword: GRI

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Study of Ignition Characteristics of CH4/Hot Air Diffusion Flame Using a Flame-Controlling Continuation Method (화염제어 연속계산법을 이용한 CH4-고온공기 확산화염의 점화특성 연구)

  • Song, Keum-Mi;Oh, Chang-Bo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.6
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    • pp.625-632
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    • 2011
  • The ignition characteristics of a $CH_4$/hot air counterflow diffusion flame were investigated numerically using a flame-controlling continuation method. For the chemical reactions, the GRI-v1.2 reaction mechanism was used in the simulation. The maximum flame temperature was presented in the space of the inverse global strain rate, and showed S-curve-type behavior. The flame temperatures and velocities of the upper and middle branches were compared for different global strain rates. In addition, the global strain rate was compared with the local strain rates defined at the flame surface and the boundaries of the fuel and oxidizer sides of the fuel/air mixing layer. These local strain rates correlated well with the global strain rate.

Application of Yonsei-Yale isochrones to Globular Clusters in gri band

  • Lim, Dong-Wook;Han, Sang-Il;Chun, Sang-Hyun;Kim, Myo-Jin;Shon, Young-Jong
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.2
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    • pp.83.1-83.1
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    • 2010
  • Recent observations of Sloan Digital Sky Survey (SDSS) for the ugriz filters have provided the largest and the most homogeneous photometric database. Especially, the ugriz systems have been used in many telescopes, such as SDSS, CFHT, and Gemini, and will be applied next generation large telescopes. In addition, many stellar evolution models, like as PADOVA, BaSTI and DSEP, have introduced theoretical isochrones in ugriz system, to apply the isochrones into the photometry of stars in globular clusters. In this study, we transformed Yonsei-Yale($Y^2$) isochrones to ugriz photometric system and fit the isochrones to the (g-r, r), (g-i, r), and (r-i, r) CMDs of 13 globular clusters (Chun et al. 2009, Clem et al. 2008, An et al. 2008). We found that the derived ages from $Y^2$-isochrones are 1~3Gyr younger and the estimated distance moduli are 0.3mag larger than the values inferred from the other isochrones in r-band. Also, the E(B-V) are 0.02~0.04mag less than those estimated from the other models. The ages of each globular cluster estimated from $Y^2$-isochrones are 12~14Gyr and distance moduli show good agreement with previous studies. From this result, we confirmed the availability of the $Y^2$-isochrones in gri filters. However, it is a problem which will improve that E(B-V) values obtained from $Y^2$-isochrones are too small. Finally, the result of this study is expected to be used research of globular cluster in ugirz photometric system.

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Accuracy of the Loran-C Fix in Cheju Areas (제주지역에서의 Loran-C 위치의 정도)

  • Kim, Gwang-Hong;Sim, Hyeong-Il;Jang, Chung-Sik
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.21 no.2
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    • pp.123-130
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    • 1985
  • This paper was conducted for the purpose of evaluating the accuracy of the observed time difference in Loran-C when the ground wave propagated on the surface included both land sea. The time difference of X and Y station in North East Pacific Chain GRI 5970 was measured at 25 points in Cheju areas. The results obtained are as follows: (1) The errors of time difference for M-X pair are increased when the Loran-C wave propagates above 500m heights of Hanla mountain on propagation path between the observed point and master or X, Y slave station. (2) The errors of time difference for M-X pair are able to decrease by way of correction for the propagation velocity and the geodetic datum, but errors of the time difference for M-Y pair very irregularly because irregular terrain include in propagation path from X station and propagation path from Y station is twice longer than X station. (3) It is confirmed that accuracy of Loran-C fix can elevate by the way of all correction for a geodetic datum transformation, the propagation velocity with refractive index of radio wave and the propagation velocity over land.

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A Decade of the National Institute for Materials Science as an Independent Administrative Institution

  • Kishi, Teruo;Takemura, Masahiro
    • STI Policy Review
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    • v.3 no.2
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    • pp.152-171
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    • 2012
  • In April 2001, many Japanese national institutes were reorganized as Independent Administrative Institutions (IAI) based on the General Act for Independent Administrative Institutions and the act for each institution. Under the Ministry of Education, Culture, Sports, Science and Technology (MEXT), the National Institute for Materials Science (NIMS) was established by the merger of the National Research Institute for Metals (NRIM) and the National Institute for Research in Inorganic Materials (NIRIM). One of the biggest changes was the expansion of autonomous administration. The nanotechnology and material R&D field was prioritized in the 2nd (2001-2005) and the 3rd (2006-2010) Science and Technology Basic Plans; subsequently, NIMS was assigned to take the initiative in nanotechnology as well as materials science. NIMS has proactively expanded research fields through the introduction of researchers from polymers, electronics, and biotechnology as well as member institutes of the World Materials Research Institute Forum (WMRIF). Globalization has been promoted through programs that include the International Center for Young Scientists (ICYS) and the International Center for Materials Nanoarchitectonics (MANA). The 4th Science and Technology Basic Plan (2011-2015) emphasizes outcomes-recovery and rebirth from the disaster, green innovation, and life innovation. The Midterm Plan for NIMS also follows it. R&D collaboration by multi-partners (that include industry, university, and GRI) should be strategically promoted where GRI are especially required to play a hub function for innovative R&D and open innovation. NIMS highlights are Tsukuba Innovation Arena (TIA) and the Nanotechnology Platform Project. On January 20, 2012, a new organization was decided on by the Japanese Government where several IAI from different science and technology areas will be merged to realize more effective R&D as well as administrative cost reductions. NIMS is also supposed to be merged with 4 other R&D IAI under MEXT by the end of 2013.

Societal Challenge-driven Innovation in GRIs and Sustainability Transition : Focus Group Interview (지속가능한 전환의 관점에서 본 출연(연) 사회문제 해결형 연구개발의 현황과 과제 : 포커스 그룹 인터뷰를 중심으로)

  • Song, Wichin;Seong, Jieun
    • Journal of Korea Technology Innovation Society
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    • v.22 no.1
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    • pp.1-27
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    • 2019
  • This study deals with the changes in the government-funded research institutes (GRI) in terms of 'responding to social challenges and turning to the institutes that are pursuing sustainability transition'. The newly established societal problem-solving R&D projects in GRIs are core experiments for the transition. In order to discuss about the prospect of transition of GRIs, this study used focus group interview approach. In the interview, the GRIs's stance on the societal problem-solving R&D projects, and its process, problems and the policy direction had been discussed. It is suggested that the necessity of transition is discussed and transition experiments are proceeding on a small scale, but experiments are still underway in the existing framework. In order to facilitate the transition in GRIs, it is necessary to carry out the experiment and the vision making work from the inside the GRI.

Effects of Sprouting Degree and Threshing Methods on Germination and Seedling Vigor in Barley (보리의 수발아정도 및 탈곡방법이 종자활력 관련 형질에 미치는 영향)

  • Lee, Eun-Sup;Chun, Jong-Un
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.36 no.1
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    • pp.65-69
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    • 1991
  • In order for investigating the factors related to decrease of seedling vigor in the naked barley lines, two naked lines and a covered variety were sprouted with 20 mm rainfall in the natural condition, dried and the sprouted seeds were threshed by hand and small machine thresher, Chiyota. In the case of hand-threshing of the sprouted seeds, the germination rate index (GRI), germination rate, and TTC test value of the different varieties were not different due to the different sprouting degrees, but emergence rate index (ERI) became decreased with stronger sprouting damage. In comparison with hand-threshing, the embryos of sprouted seeds from machine threshing with 700 rpm were partially damaged, and the traits related to seedling vigor were decreased highly significantly. However, the diastatic activity was sharply increased by stronger sprouting and machine threshing. The sprouting degree in the hand-threshing plot was significantly correlated with the diastatic activity(r=0.931**, 0.951**) and GRI(r=0.461), respectively.

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Two-zone Modeling for Combustion Processes of HCCI Engine (균일 예혼합 압축착화 엔진 연소과정의 Two-Zone 모델링)

  • Lee Myunghoon;Kim Kunhong;Kim Yongmo
    • Transactions of the Korean Society of Automotive Engineers
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    • v.13 no.3
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    • pp.74-79
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    • 2005
  • The Homogeneous Charge Compression Ignition(HCCI) combustion is currently under intensive investigation because of its potential to increase thermal efficiency while greatly decreasing NOx and p.M. In order to account for the thermal boundary layer effects, the two-zone model has been developed to analyze the combustion characteristics of HCCI engine. The detailed chemistry are represented by the GRI mechanism 3.0 involving 53 species and 325reactions. The present combustion model has been validated against the experimental results. Computations are also made for the wide-range operating conditions of HCCI engine.

A Study on the Laminar Burning Velocity Using an Angle Method and Annular Diverging Channel Combustor and Characteristics Of Chemiluminescence (각도법과 동심형 확장 채널 연소기를 이용한 연소속도 측정 및 화염 발광 특성에 관한 연구)

  • Yun, Seungho;Lee, Keeman
    • 한국연소학회:학술대회논문집
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    • 2014.11a
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    • pp.91-94
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    • 2014
  • In this study, the laminar burning velocities of SNG fuel were studied using both experimental measurements and kinetic simulations. They were measured using the angle method of Bunsen flame configuration and the annular diverging channel combustor. And they were also numerically calculated by CHEMKIN Package with GRI 3.0 mechanisms. Spectrometer was used for characteristics of flame chemiluminescence of SNG fuels. From results of this work, first, we found that according to adding $H_2$ contents in the fuels the laminar burning velocities of SNG fuels were increased. And second, we also discovered existence of OH*, CH*, $C_2*$, HCO*, $CH_2*$ radicals and their correlation.

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A Study on Models of Graduate Courses in Governmental Research Institutes (출연(연) 단설대학원 운영모델 연구)

  • 김갑수;김전식;김정흠;이규호;이병민;조붕제;현병환
    • Journal of Korea Technology Innovation Society
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    • v.1 no.2
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    • pp.165-180
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    • 1998
  • This study suggests a new concept for the improvement of productivity and innovativeness of governmental research institutes(GRIs) : GRIs can also accomodate a special graduate course. Through the combination of educational function and research activities, the explict and tacit knowledge made by GRIs could be efficiently diffused to other sectors of national innovation system, especially industries. This study suggests three different models of graduate courses : independent course in each GRI, joint course by several GRIs, and joint course linking GRIs and university.

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NOx Emission Characteristics in Parametrically Varied Methane-Air Coflow Flames (메탄 분류 화염에서의 연소 조건에 따른 NOx 배출 특성)

  • Lee, Sang-Han;Oh, Chang-Bo;Lee, Chang-Eon
    • 한국연소학회:학술대회논문집
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    • 2000.05a
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    • pp.35-44
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    • 2000
  • It was numerically studied that NOx emission characteristics of confined $CH_{4}$ jet flames with the variation of the diameter of inner fuel nozzle, the flow rate of $CH_{4}$ and equivalence ratio. Parabolic type equations were adopted in the calculation and GRI-2.1I mechanism was used for the chemical reaction. NOx emission index (EINOx) was introduced to evaluate NOx emission quantitatively in parametrically varied flames and the contribution of Thermal and Prompt NO mechanism was discussed. The results showed that Total EINOx varied sensitively with the variation of the flow rate of$CH_{4}$ but it was not sensitive to the variation of the diameter of inner fuel nozzle. Thermal EINOx showed the similar tendency to total EINOx and Prompt EINOx showed insensitivity to the variation of the diameter of inner fuel nozzle and the flow rate of $CH_{4}$.

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