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Study on Characteristics of Reforming by TPOX in Perforated SiC Tube (열적부분산화법을 적용한 Perforated SiC 관의 개질특성연구)

  • Lee, Pil Hyong;Cha, Chun Loon;Hong, Seong Weon;Im, Hyun Jin;Hwang, Sang Soon
    • 한국연소학회:학술대회논문집
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    • 2012.04a
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    • pp.25-27
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    • 2012
  • In this paper, combustion process in the perforated silicon carbide(SiC) tube using a two dimensional approaches with GRI Mechanism 1.2 was investigated. The computational mesh structure which is divided into $60{\times}15$ and boundary conditions are set to constant mass flow rate at the inlet and constant pressure condition at the outlet respectively. Its result shows that the temperature on this peak was roughly 100K higher than the adiabatic flame temperature of 2223K for a free laminar flame at these conditions.

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An Experimental on Cellular Instability and Laminar Burning Velocity of SNG Fuel (SNG 연료의 셀 불안정성 및 층류연소속도에 관한 실험적 연구)

  • Kim, Dongchan;Jo, Junik;Lee, Keeman
    • 한국연소학회:학술대회논문집
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    • 2015.12a
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    • pp.109-112
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    • 2015
  • This article describes a cellular instability and laminar burning velocity of simulated synthetic natural gas(SNG) including 3% hydrogen. In this study, experimental apparatus is employed using cylindrical bomb combustor, and investigation is carried out with high speed camera and Schlieren system. The cellular instability is caused by the buoyancy, hydrodynamic instability. Unstretched burning velocity can be determined by extrapolated stretch rate of zero point from measured results. These results were also compared with numerical calculation by Chemkin package with GRI 3.0, USC-II, WANG, C3 Fuel mechanism. As an experimental conditions, equivalence ratios was adjusted from 0.8 to 1.3. From results of this work, the one was found that the cellular instability has occurred by effect of thermal expansion rate and flame thickness. As the other results, unstretched laminar burning velocity was best coincided with GRI 3.0 mechanism.

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Comparison of Laminar Burning Velocity of CH4/C2H4/Air Mixtures with Consideration of Chemical Mechanism (에틸렌 첨가에 따른 메탄 화염점파속도와 화학반응 메카니즘 비교 및 선형, 비선형 모델 평가)

  • Van, Kyu Ho;Yang, Jae Young;Park, Jeong;Kwon, Oh Boong;Lee, Dae Keun;Kim, Seung Gon;Guahk, Young Tae;Noh, Dong-Soon;Yoon, Jin Han;Keel, Sang In
    • 한국연소학회:학술대회논문집
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    • 2015.12a
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    • pp.165-168
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    • 2015
  • To measure laminar burning velocity in methane/air/ethylene mixture flame, propagating centrally ignited spherical premixed flame to radial direction was measured by high-speed schlieren images with elevated pressure. In this study, The experimentally measured unstretched laminar burning velocities of methane was compared with GRI mech 3.0 to validate experimental data and choose the radius range, respectively. numerical prediction using the PREMIX code with GRI mech 3.0, USC mech II,, and Wang mech were evaluated through comparison with experimental burning velocity with consideration of extrapolation on linear/nonlinear model.

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A Study on Measurement of Laminar Burning Velocity and Markstein Length of SNG Fuel in Spherical Propagation Flame (구형 전파화염에서 SNG 연료의 층류연소속도와 마크스타인 길이 측정에 관한 연구)

  • SONG, JUNHO;LEE, KEEMAN
    • Journal of Hydrogen and New Energy
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    • v.30 no.1
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    • pp.67-75
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    • 2019
  • An experimental study was conducted to measure laminar burning velocity and Markstein length of SNG fuel with 3% of hydrogen contents from spherical propagating flames at normal and elevated initial pressure. These results were compared with numerical calculations by Premix code with GRI-mech 3.0, USC II and UC San Diego to provide suitable mechanism for SNG fuel. As a result of this work, it was found that the burning velocities and Markstein lengths of SNG fuel decrease with increase of initial pressure regardless of equivalence ratio. In addition, numerical calculations with GRI-mech 3.0 were coincided with experimental results.

A Study for ESG (Environment Social Governance) in Tourism Industry (관광산업 분야 ESG (Environment Social Governance)를 위한 시론적 연구)

  • Eunju Woo
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.3
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    • pp.239-247
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    • 2023
  • As an industry that serves as a greater catalyst for social and cultural exchange than any other industry, the tourism industry has a strong responsibility toward sustainable management in economic, social, and environmental respects. However, there is a low level of awareness for ESG(environmental, social, governance), and as of now, only companies whose parent company is a large corporation are interested in ESG. Moreover, tourism companies taking part in ESG only focus on the environmental field of ESG. Thus, the present study attempted to understand the current status of ESG research in the tourism field and, based on this understanding, offer a field of research urgently in need. Based on the research results, the study found that awareness studies on the type of ESG management that stakeholder groups take into consideration must take place in advance in order to understand and develop ESG for the tourism industry. Additionally, ESG evaluation variables that reflect the characteristics of the tourism industry must be developed. Lastly, strategies and techniques that objectively disclose ESG management activities are necessary based on a disclosure strategy presented by GRI(Global Reporting Initiative).

The Recent Practice of Evaluation of Government-sponsored Research Institutes(GRIs) in Korea : From Retrospective to Forward-looking perspective (이공계 정부출연(연) 기관평가모형개발 및 적용사례 연구)

  • 이철원;현재호
    • Proceedings of the Technology Innovation Conference
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    • 1998.06a
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    • pp.131-163
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    • 1998
  • The interest in the evaluation of government-sponsored research institutes (GRIs) has increased markedly in Korea in 1990s; this is mainly because of the increasing needs 1) to improve the quality of R&D at GRIs, and 2) to reorient the GRIs' strategic position in Korean national innovation systems due to the enhancement of R&D capabilities of private companies and universities during last decade. As a first attempt to diagnose the managerial and strategic issues of GRIs, a Multi-Ministerial Evaluation Committee was established as an ad hoc task force under the Prime Minister's Office in 1991. According to the recommendations of the committee, the Ministry of Science and Technology (MOST) to which most of GRIs were affiliated, made it a rule to evaluate the annual performance of GRIs since 1992. This paper examines the recent experience of MOST's evaluation of Government-sponsored Research Institute in Korea. After several years'efforts of Science & Technology Policy Institute(STEPI) to build prospective evaluation systenL MOST decided to apply two supplementary approaches for the evaluation of GRIs; one is summative annual evaluation and the other is formative 3-year evaluation. The annual evaluation system that is designed as a temporary measure is to monitor and to guide the self-evaluation activities of GRIs. In the process of annual evaluation, MOST tries to minimize its direct involvement, and allows each GRI to develop self-evaluation system that is most appropriate for the unique characteristics of the institute. If there exist urgent issues under scrutiny, however, it can be incorporated and examined by a group of external experts as special issues in the annual evaluation system. The aim of 3-year evaluation is both to examine the past performance of each GRI and to investigate whether the strategic role of each GRI is viable in the future. Its major focus, however, lies not on auditing past performance but on strengthening future strategic position of each GRI. The MOST designates a group of evaluation experts with appropriate knowledge and competence as members of the General Evaluation Committee for one year. With the help of STEPI, a specialized research institute for R&D evaluation, the General Evaluation Committee develops methodology and procedures for the actual evaluation of GRIs. Based on the evaluation reports and recommendations from the General Evaluation Committee, the MOST develops various policy measures for strengthening GRIs.

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Lithium atoms adsorbed on graphene

  • Kim, ChanRan
    • Proceeding of EDISON Challenge
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    • 2013.04a
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    • pp.278-281
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    • 2013
  • We investigate special arrangements of lithium atoms adsorbed on graphene. By changing adsorption sites and increasing number of atoms, adsorption of lithium atoms on ($3{\times}3$) graphene is investigated using the density functional theory (DFT) calculations. In this study, three kinds of adsorption sites are considered, such as top, bridge and hollow sites.

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Regional Distribution of Government-sponsored Research Institutes in Science & Technology (이공계 정부출연연구기관의 지방이전방안)

  • Chung Sun-Yang
    • Journal of Korea Technology Innovation Society
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    • v.8 no.spc1
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    • pp.410-432
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    • 2005
  • Korea's government-sponsored research institutes (GRIs) have contributed a lot to the economic development of Korea. They have become major components of the Korean national innovation system. However, in these days, they have been blamed for low productivity and inefficiency, as well as insufficient contribution to national development. This paper argues that the major problem of Korea's GRIs lies in their concentration in a few regions, e. g. Seoul, Gyeonggi, and Daedeok. It argues that they should be fairly distributed among regions in order to contribute to the development of Korea effectively. In this regard, this paper explores the relevant policy options to effectively distribute Korean GRIs among regions. It suggests two categories of distribution scenarios. The first category is based on the types of GRIs to be distributed. This category has three scenarios: existing GRIs, branch institutes of existing GRIs, and new GRIs. The second category is based on the jurisdiction of GRIs. It has also three scenarios: GRI system as an independent sector, GRI-university cooperation system, and integration of GRIs to regional universities. These scenarios have advantages and disadvantages, respectively. Therefore, we must find a rather satisfactory scenario based on the mixture of scenarios of both categories.

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Experimental and Numerical Investigations on Detailed Methane Reaction Mechanisms in Oxygen Enriched Conditions (산소부화조건의 메탄 상세반응기구에 대한 실험 및 수치해석 연구)

  • Han, Ji-Woong;Lee, Chang-Eon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.2
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    • pp.207-214
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    • 2004
  • The burning velocities of conventional and oxygen-enriched methane flame in various equivalence ratio were determined by experiments. The validity of existing reaction mechanisms was examined in oxygen-enriched flame on the basis of the experiment results. Modified reaction mechanism is suggested, which was able to predict burning velocity of oxygen enriched flame as well as methane-air flame. Complementary study on reaction mechanisms shows the following results : Present experiment data were found to be more reliable in comparison with existing ones in a oxygen-enrichment condition. It was found that some modification in existing reaction mechanisms is necessary, since discrepancy between measurements and predictions is increasing with oxygen enrichment ratio. The sensitivity analysis was performed to discriminate the dominantly affecting reactions on the burning velocity in various oxygen enrichment and equivalence ratio. A modified GRI 3.0 reaction mechanism based on our experiment results was suggested, in which reaction rate coefficients of (R38) H+O$_2$<=>O+OH in GRI 3.0 reaction mechanisms were corrected based on sensitivity analysis results. This mechanism showed a good agreement in predicting the burning velocity and number density of NO in oxygen-enriched flame and would provide proper reaction information of oxygen-enriched flame at this stage.

Relevance Analysis of Performance Evaluation Systems of Government S&T Research Groups (출연연구기관의 연구회 단위 기관평가제도의 적합성 분석)

  • Nam, Yeong-Ho;Kim, Byeong-Tae
    • Journal of Technology Innovation
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    • v.14 no.3
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    • pp.117-154
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    • 2006
  • This research examines performance evaluatees' opinions regarding the current institutional performance evaluation systems of Government S&T Research Institutes (GRIs). Under the current evaluation systems, twenty GRIs are grouped into three Research Groups and each Group has its own evaluation systems. One problem of the current institutional evaluation systems is that the systems cannot reflect individual GRIs' characteristics. The following methods are used. First, based on four perspectives of Kaplan & Norton(1992)'s Balanced Scorecard(BSC) model, six perspectives appropriate to GRUs' characteristics are derived. Second, experts classify current performance evaluation measures into the six perspectives. This enables different evaluation systems of three GRI Research Groups to be compared under the same evaluation measures. Third, GRIs' evaluatees are asked to allocate appropriate weights on the performance measures. Evaluatees' weights of a GRI are compared with average weights of the related Group. Finally in every BSC's perspective, GRIs that have extraordinarily over-scored or under-scored weights are analyzed in terms of GRIs' missions, customers, capability of human resources, etc. In the Basic Research Group, the Korea Basic Science Institute is deviated in the financial perspective and the strategic direction perspectives. In the Public Research Group, Korea Institute of Construction Technology is significantly different from other GRIs in three perspectives. Five out of eight GRIs in the Industrial Research Group, GRIs are significantly different each other in several perspectives. It could be concluded that the current institutional evaluation systems are least appropriate in measuring performance of the GRIs of the Industrial Research Group.

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