324,617 research outputs found
Combustion Control using Two-Stage Diesel Fuel Injection in a Single-Cylinder PCCI Engine
No full text2004 SAE Congress, Detroitby the
national research laboratory scheme, Korea and in part by
the Brain Korea 21 Project
The Influence of Intake Air Boosting and EGR on Diesel-Fueled HCCI Combustion in a DI-Diesel Engine
Full text linkTHIESEL 2006 ConferenceThe authors would like to appreciate the support by CERC (Combustion Engineering Research Center) and Fu-ture vehicle technology development corps, Korea
Dialektikah verharmoniyah betefisot hahistoryah vehameshihiyut shel ha-Rav Kook
No full textAdded title page in English: Dialectics and harmony in the concepts of history and messianism of Rav Kook.This essay will attempt to examine Rav Kook's corpus of thought from the viewpoint of its systems of methodological foundations: dialectic and harmonistic. These two elements are the dominant components of his thought, both from the methodological and ontological aspects. As to the harmonistic element, it should be noted that Rav Kook's entire corpus of thought is stamped with the idea of monistic unity, and he believes in the unity of existence from the point of view of ontological monism. The monism is inherent even in the center of the theoretical method, or in the words of Rav Kook: "The various thoughts actually don't contradict each other, everything is but a unitary revelation which appears in different sparks"
and Choongsik Bae, "Homogeneous Charge Compression Ignition Engine with Two-Stage Diesel Fuel Injection," Proc. THIESEL2004 (Thermo-and fluid dynamic Processes in Diesel Engines), pp497-510, Valencia, Sep. 2004.
No full textProc. THIESEL2004 (Thermo-and fluid dynamic Processes in Diesel Engines), pp497-510A diesel-fueled homogeneous charge compression ignition (HCCI) combustion technique using a two-stage injection strategy has been investigated in a single cylinder optical engine equipped with a commonrail fuel system. Although HCCI combustion has the advantages of reducing NOx and PM emissions, difficulties in vaporization of a diesel fuel and control of the combustion phase hinder the development of the HCCI engine. A two-stage injection strategy was applied to relieve these problems. Premixing of diesel fuel with air was realized mainly by the early injection strategy. The first injection, named as main injection, was an early direct injection of diesel fuel into the cylinder to achieve premixing with air. The second injection was a diesel injection of a small quantity (1.5 ㎣) as an ignition promoter and combustion phase controller near TDC. Effects of injection pressure and intake air temperature were studied with two-stage injection strategy. Concerning the injector geometry, a hole-type injector (5 holes) with small injection angle (100°) instead of conventional angle (150°) was applied to minimize the over-penetration that may prevent forming a premixed charge due to wall wetting. The multi-hole injector (14 holes) was also tested to maximize the atomization of spray. The experimental results showed that the two-stage injection could be used as a combustion phase controller only in the case of a low intake air temperature, but maintained the effect of ignition promotion although the ignition timing was advanced by the high intake air temperature. The main injection timing should be advanced earlier than BTDC 100°CA for the homogeneous and non-luminous combustion. The small injection angle was effective to minimize the overpenetration, and the multi-hole injector was effective to maximize the atomization so that the power output was increased, and exhaust gas was decreased. Exhaust results of the HCCI combustion optimized by this parametric study showed reduced NOx by more than 90% but increased HC, CO emissions compared with the conventional direct-injection (DI) diesel engine operation in the same engine. In addition, the application of the alternative gaseous fuel such as dimethyl ether (DME) was discussed implying the practical potential of HCCI operation.by the National Research Laboratory scheme, Korea and in
part by the Brain Korea 21 Project
Diffusive author(s), cohesive author: Analysis of S/N (1994)
No full textThis study indicates the ways in which various aspects of the author(s) are brought forth in Dumb type’s performance art, the S/N production. Previous research has suggested a non-hierarchical organization of Dumb type and the absence of a “privileged author” in Dumb type’s collaborative work, S/N. However, the results that I have investigated from member’s interviews on the creative process of S/N along with my analysis of the recorded images of S/N, indicate a different aspect of the author(s). First, S/N was created through, so to speak, the collective ideas of the members of Dumb type. Further, S/N has at least nine quotations from previous performances, installations, and printed writings, besides the work-in-progress technique. Explicating one of the “author functions” as given by Michel Foucault, each text has plural subjects of the author. However, it has been revealed from members’ interviews that Teiji Furuhashi had a decision-making role in selecting the members’ ideas within the performance. Since then, S/N has had plural subjects of creation; however, Furuhashi is one of the subjects of creation along with the “privileged author.” S/N has plural authors (diffusive authors) yet at the same time, it has a “privileged author,” Teiji Furuhashi (cohesive author)
Diesel Combustion Strategy and Its Extension
Full text linkInternational Conference for Automotive Engineering, POSTECH, 2003. 12.supported by the national research laboratory scheme, Korea
Diesel-fuelled homogeneous charge compression ignition engine with optimized premixing strategies
Full text linkThe operation of a diesel-fuelled homogeneous charge compression ignition (HCCI) engine was studied in a single-cylinder, direct-injection diesel engine with regard to three key parameters: spray penetration, time for premixing, and dilution of the premixed charge. The relationships between these parameters were clarified through spray measurements, flame imaging, and combustion analysis. The spray penetration was. optimized by a small included angle to avoid wall impingement at low pressure and temperature in the cylinder. However, the hole diameter did not affect spray penetration. Sufficient time for premwng was realized by advanced injections earlier than 100 crank angle degrees (CAD) before top dead centre (BTDC) at 800 r/min. Dilution of the premixed charge to control ignition timing was investigated by adopting exhaust gas recirculation (EGR). The optimized premixing strategies of twostage injection, with a small amount of the ignition-promoting fuel (1.5 mm(3))-which was injected near TDC to assist the combustion of a premixed charge (10 mm(3))-resulted in an indicated mean effective pressure of up to 250 kPa within 3 per cent fluctuation, along with a significant reduction in particle matter and nitrogen oxides emissions, while 46 per cent EGR rate was applied to the premixed charge with preheated intake air at 433 K.The authors would like to express their appreciation for support by the National Research Laboratory scheme, Korea and in part by the Hyundai Motor compan
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
The application of diesel-fueled HCCI combustion in an automotive-size single-cylinder diesel engine
Full text linkSupport for this research was provided by the CERC (Combustion Engineering Research Center) and Future vehicle technology development corps of Korea. The research was performed at the engine laboratory of the department of mechanical engineering, KAIST. KAIST is a research-oriented educational institute operated by Korea Ministry of Science and Technology. Thanks are also due to Paul Miles of Sandia National Laboratories for his original idea in analyzing the combustion efficiency, work conversion efficiency, and fuel conversion efficiency
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