排序方式: 共有26条查询结果,搜索用时 0 毫秒
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P. K. Bose K. Roy N. Mukhopadhya R. K. Chakraborty 《International Journal of Automotive Technology》2010,11(1):1-10
Particulate matter is considered to be the most harmful pollutant emitted into air from diesel engine exhaust, and its reduction
is one of the most challenging problems in modern society. Several after-treatment retrofit programs have been proposed to
control such emission, but to date, they suffer from high engineering complexity, high cost, thermal cracking, and increased
back pressure, which in turn deteriorates diesel engine combustion performance. This paper proposes a solution for controlling
diesel soot particulate emissions by an improved theoretical model for calculating the overall collection efficiency of a
cyclone. The model considers the combined effect of collection efficiencies of both outer and inner vortices by introducing
a particle distribution function to account for the non-uniform distribution of soot particles across the turbulent vortex
section and by including the Cunningham correction factor for molecular slip of the particles. The cut size diameter model
has also been modified and proposed by introducing the Cunningham correction factor for molecular slip of the separated soot
particles under investigation. The results show good agreements with the existing theoretical and experimental studies of
cyclones and diesel particulate filter flow characteristics of other applications. 相似文献
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Roy Van Den Berg Peter W. De Langen Paul C.J. Van Zuijlen 《WMU Journal of Maritime Affairs》2017,16(3):421-438
A review of seven large landlord port authorities around the world reveals a notable diversity of pricing structures. While port authorities increasingly act as commercial undertakings, port pricing often seems to be not driven by commercial considerations. In this paper, we argue that ports can be regarded as “business ecosystems” with multiple users. This provides a valuable perspective on pricing and raises the question of whether ports can be regarded as two-sided markets. We argue this is not the case. The business ecosystem perspective provides a basis for deducing seven pricing principles for port authorities that are detailed in the paper and illustrated with cases these principles. These pricing principles are broadly follow a direct user pays approach; capture value from “non-core” tenants; price aggressively for activities with a high strategic value; differentiate pricing based on price elasticity and connectivity improvements; maximize revenue from long-term lease agreements, price port dues competitively; critically consider differentiation of charges based on environmental performance; and finally use incentives to align interests of terminal operators and shipping lines. We conclude that the ecosystem perspective is central to the understanding of pricing decisions of port authorities and that various pricing issues deserve more attention. 相似文献
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介绍了Resco Engineering公司研发的货车用构架式径向转向架.经AAR试验表明,与常规转向架及性能良好的转向架相比,Resco径向转向架的曲线通过能力非常优越,动力学稳定性极好.从经济效益角度,概述了采用Resco径向转向架所能产生的一系列节约效果. 相似文献
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The present study attempts to address the challenges of the multiobjective optimization problem of the BSFC-NOx-PM trade-off paradox of an existing diesel engine by harnessing the synergetic benefit of PM and BSFC reduction through CRDI operation and simultaneous NOx reduction by EGR application. Load, FIP and EGR were chosen as the input parameters while NOx, PM and BSFC were the response variables. In order to reduce the experimental effort, the Taguchi L16 orthogonal array technique was employed to obtain the corresponding values of the response variables. The grey relational analysis coupled with fuzzy logic has been employed as the optimization routine. The optimal combination of the input parameters corresponding to the calibrated values of the response variables were obtained by employing the Grey-Fuzzy Grade and S-N ratio strategy as a performance index. The computed optimal combination so obtained were further validated through actual experimentation. EGR was found to be the most influencing factor in the present optimization endeavour. The study also established that the Grey-Fuzzy-Taguchi method was not only comparable but superior to the Grey-Taguchi method usually employed for such optimization studies. 相似文献
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