• Title/Summary/Keyword: Alternative Gas

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Emission Reduction using Unburned Exhaust Gas Ignition (미연배기가스 점화 기술을 이용한 배기저감)

  • 김득상;강봉균;양창석;조용석
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.3
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    • pp.39-47
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    • 2003
  • UEGI (Unburned Exhaust Gas Ignition) is an alternative method for fast light-off of a catalyst. It ignites the unburned exhaust mixture using two glow plugs installed in the upstream of the close-coupled catalysts. In addition, a hydrocarbon adsorber was applied to the UEGI, for more effective reduction of HC emission. Engine bench tests show that the CCC reaches the light-off temperature laster than the baseline exhaust system and HC and CO emissions are reduced significantly during the cold start. From the vehicle test, it was observed that a few amount of HC emission was reduced even the catalysts were aged. It is expected to develop a solution kit applicable to a new vehicle or used one, to meet the emission regulation

Characteristic Analysis of a SCR System using a Metal Foam in Diesel Engines (디젤 엔진에서 금속 폼을 적용한 SCR 촉매의 특성 분석)

  • Kim, Yongrae;Choi, Kyonam
    • Journal of ILASS-Korea
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    • v.18 no.4
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    • pp.196-201
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    • 2013
  • SCR(Selective Catalytic Reduction) is a major after-treatment solution to reduce NOx emission in recent diesel engines. In this study, a metal foam is applied as an alternative SCR substrate and tested in a commercial diesel engine to compared with a conventional ceramic SCR system. Basic engine test from ND-13 mode shows that a metal foam catalyst has lower NOx conversion efficiency than a ceramic catalyst especially over $350^{\circ}C$. A metal foam catalyst has characteristics of high exhaust gas pressure before a SCR catalyst and high heat transfer rate due to its material and structure. NOx conversion efficiency of a metal foam catalyst shows an increasing tendency along with the increase of exhaust gas temperature by $500^{\circ}C$. The effect of urea injection quantity variation is also remarkable only at high exhaust gas temperature.

Exhaust Gas Recirculation Control in a Spark-Ignition LPG Engine Using Neural Networks

  • Cui, Hongwei;Liu, Vifang;Zhai, Yujian
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.68.3-68
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    • 2002
  • This paper presents a neural network approach to control exhaust gas recirculation(EGR) in a Liquefied Petroleum Gas(LPG) engine. In order to meet Increasingly stringent automotive exhaust emission regulations, alternative fuels such as LPG engines have been developed in many countries. HC&CO emissions of LPG engines can be easily reduced through air-fuel ratio control, but the control effect on NOx reduction is not good enough. Consequently EGR system is introduced to achieve a significant reduction in NOx emissions. Conventional EGR control uses the mapping method. The calibration time is long and the work is complex when adopting this mapping method. However neural networks are suitable f...

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토양의 자연정화능과 다기능성 Colloidal Gas Aphron을 이용한 지하 환경에서의 BTEX 처리기술 개발

  • 박주영;남경필
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.09a
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    • pp.269-272
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    • 2004
  • The use of colloidal gas aphron (CGA), as an external oxygen carrier, provides a promising alternative to promote aerobic bioremediation of BTEX in the subsurface environment. CGA is a stable bubble supported by three surfactant layers and can supply oxygen below the soil surface uniformly due to its plug-flow characteristic. Since CGA has a hydrophobic layer that can act as a partitioning medium for hydrophobic contaminants it is known to facilitate desorption of soil-sorbed contaminants. In addition, bioaugmentation and biostimulation are possibly achieved by using CGA when generated from a solution containing BTEX-degrading microorganisms and appropriate nutrients. In this study, we presented the physico-chemical characteristics of CGA generated from a solution composed of microorganisms and nutrients. The applicability of CGA as an in situ aerobic bioremediation technology of BTEX will be further evaluated.

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Analysis of Design and Part Load Performance of a Modified Regenerative Cycle Gas Turbine (수정된 재생사이클 가스터빈의 설계 및 부분부하 성능해석)

  • Hwang, Sung-Hoon;Kim, Tong-Seop
    • 유체기계공업학회:학술대회논문집
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    • 2005.12a
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    • pp.467-472
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    • 2005
  • Characteristics of a Modified regenerative cycle gas turbine has been investigated. In the cycle, the turbine expansion is divided into two parts and the regenerator locates between them. Two types of mechanical design are assumed: two-shaft and single-shaft. In particular, optimal pressure ratio division between the high and low pressure turbines is evaluated for the single shaft configuration. The part load analyses have been carried out with the aid of off-design models. In addition to the general fuel only control, a variable speed control is assumed as the part load operating strategy of the single shaft configuration. Obvious advantage with the alternative cycle is observed in the variable speed operation of the single shaft design.

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Cell Design for Mixed Gas Fuel Cell (혼합가스 주입형 연료전지를 위한 전지 디자인)

  • Park, Byung-Tak;Yoon, Sung Pil
    • Journal of the Korean Ceramic Society
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    • v.42 no.12 s.283
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    • pp.860-864
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    • 2005
  • In this study, we fabricated honeycomb type Mixed-Gas Fuel Cell (MGFC) which has advantages of stacking to the axial direction and increasing volume power density. Honeycomb-shaped anode with four channels was prepared by dry pressing method. Two alternative channels were coated with electrolyte and cathode slurry in order to make cathodic reaction sites and the others were filled with partial oxidation (POX) catalyst to increase fuel conversion. Furthermore we employed the sol-gel technique which can increase cell performance and decrease carbon coking.

Evaluation Standard of Cost-Effectiveness Analysis for Renew of Architectural Equipment in Public Building (공공건물 건축설비 갱신 계획시 비용-효율분석 평가기준에 관한 연구)

  • Jung, Soon-Sung
    • Journal of Power System Engineering
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    • v.17 no.4
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    • pp.131-138
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    • 2013
  • The purpose of this study is to suggest the evaluation standard of cost-effectiveness analysis for renew of architectural equipment in public building. Evaluation items of cost-effectiveness analysis for renew of architectural equipment in public building were used life cycle cost, energy consumption(ton of oil equivalent), green house gas emissions(ton of carbon dioxide) and maximum power demand. Life cycle cost is the process of making an economic assessment of an item, area, system, or facility by considering all significant costs of ownership over an economic life, expressed in terms of equivalent costs. The essence of life cycle costing is the analysis of equivalent costs of various alternative proposals. The social concern with green house gas and maximum power demand of architectural equipment field has been growing for the last several years.

The Turkey/Cyprus Conflict and its Implications for Russia

  • SHLAPENTOKH, DMITRY
    • Acta Via Serica
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    • v.6 no.1
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    • pp.119-140
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    • 2021
  • Relations between Ankara and Washington, which have hardly been harmonious, recently became extremely tense, especially when Turkey decided to deal with Kurdish enclaves nearby its border. Russia naturally took advantage of the tension by providing Turkey with advanced S-400 missiles and by trying to play a peacemaking role in contested regions within Syria. Ankara's dealings with Moscow alienated it from NATO and the USA, and complicated relations with Russia and its allies in Syria, where Turkey's interests collided with those of Tehran and Moscow. While these aspects of the Ankara/Moscow relationship are well known, this article explores how the discovery of natural gas in the Mediterranean has increased Ankara's importance to Moscow, as a means of sowing dissension within NATO and helping Moscow hinder the emergence of alternative gas suppliers to Europe.

Morphological Effect of Dispersed Phase on Gas Separation Properties through Heterophase Polymer Membrane: Theoretical and Experimental Approaches.

  • Park, Cheolmin;Jo, Won-Ho;Kang, Yong-Soo
    • Proceedings of the Membrane Society of Korea Conference
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    • 1996.04a
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    • pp.55-56
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    • 1996
  • Heterophase polymer system has been attractive for a potential applicability to gas separation membrane material. It has been known that there is a trade-off between gas permeability and its selectivity in common polymers. Therefore, the heterophase polymer can be an alternative for a gas separation membrane material because its transport properties can be readily controlled by blending of two different polymers. The transport properties of immiscible polymer blends strongly depend upon the intrinsic transport properties of corresponding polymers. Another important factor to determine the transport properties is their morphology: volume fraction, size and shape of dispersed phase. Although the effect of the volume fraction of the dispersed phase on the transport properties has been widely investigated, the size and shape effects have been paid attention very much. In an immiscible polymer blend of two polymers, its morphology is primarily controlled by its volume fraction of dispersed phase. Therefore, the effect of the size of the dispersed phase can be hardly seen. Therefore, a block copolymer has been commonly employed to control their morphology when each block is miscible with one or the other phase. In this work, gas transport properties will be measured by varying the morphology of the heterophase polymer membrane. The transport properties will be interpreted in terms of their morphology. The effect of the volume fraction of the PI phase and, in particular, its size effect will be investigated experimentally and theoretically.

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DETECTION OF EMISSION FROM WARM-HOT GAS IN THE UNIVERSE WITH XMM?

  • BOWYER STUART;VIKHLININ ALEXEY
    • Journal of The Korean Astronomical Society
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    • v.37 no.5
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    • pp.579-581
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    • 2004
  • Recently, claims have been made of the detection of 'warm-hot' gas in the intergalactic medium. Kaastra et al. (2003) claimed detection of ${\~} 10^6$ K material in the Coma Cluster but studies by Arnaud et al. (2001), and our analysis of the Chandra observations of Coma (Vikhlinin et al. 2001), find no evidence for a $10^6$ K gas in the cluster. Finoguenov et al. (2003) claimed the detection of $3 {\times} 10^6$ gas slightly off-center from the Coma Cluster. However, our analysis of ROSAT data from this region shows no excess in this region. We propose an alternative explanation which resolves all these conflicting reports. A number of studies (e.g. Robertson et al., 2001) have shown that the local interstellar medium undergoes charge exchange with the solar wind. The resulting recombination spectrum shows lines of O VII and O VIII (Wargelin et al. 2004). Robertson & Cravens (2003) have .shown that as much as $25\%$ of the Galactic polar flux is heliospheric recombination radiation and that this component is highly variable. Sporadic heliospheric emission could account for all the claims of detections of 'warm-hot' gas and explain the conflicts cited above.