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961.
Z.L. Yang D. Zhang O. Caglayan I.D. Jenkinson S. Bonsall J. Wang M. Huang X.P. Yan 《Transportation Research Part D: Transport and Environment》2012,17(6):478-486
This paper develops a subjective generic methodology for providing ship owners with a transparent evaluation tool for selecting their preferred NOx and SOx control techniques. We quantitatively analyse the merits of the control methods available in marine air pollution control practice using data collected from shipping companies, shipyards and maritime academies. We also prioritize the applicable control techniques with respect to operational shipping environments. 相似文献
962.
Justin D.K. Bishop Colin J. Axon Malcolm D. McCulloch 《Transportation Research Part D: Transport and Environment》2012,17(5):389-397
This paper develops a robust, data-driven Markov Chain method to capture real-world behaviour in a driving cycle without deconstructing the raw velocity–time sequence. The accuracy of the driving cycles developed using this method was assessed on nine metrics as a function of the number of velocity states, driving cycle length and number of Markov repetitions. The road grade was introduced using vehicle specific power and a velocity penalty. The method was demonstrated on a corpus of 1180 km from a trial of electric scooters. The accuracies of the candidate driving cycles depended most strongly on the number of Markov repetitions. The best driving cycle used 135 velocity modes, was 500 s and captured the corpus behaviour to within 5% after 1,000,000 Markov repetitions. In general, the best driving cycle reproduced the corpus behaviour better when road grade was included. 相似文献
963.
964.
S. Y. Hwang J. H. Lee K. K. Visuwanathan I. H. Ban 《International Journal of Automotive Technology》2013,14(1):79-90
A junction block (or electrical distribution box) is electrical equipment that has been densely assembled from components such as buss bars, relays, and fuses to control the electric current flow in vehicles. Joule heat is generated in these parts as a result of electrical bulk resistance and electrical contact resistance. The generation of heat increases due to the complex behavior of modern vehicle electronic systems. Overheated parts can be damaged during operation due to thermal energy. The thermal assessment of a junction block is an important issue in automobile development. We suggest a methodology to simulate the transient temperature distribution of buss bars and electrical relays in a junction block. A finite element formulation of a coupled electro-thermal problem, which includes the effect of Joule heating, is introduced to the simulation. Finite element analysis (FEA) and experiments at the component level of buss bars and relays are conducted to investigate the thermal performance of a junction block. To verify the accuracy of the FEA procedure, the temperature history obtained by FEA is compared with the results obtained from experiments. The thermal-electric analysis of a typical junction block assembly is also discussed. 相似文献
965.
The signalling system affects the type of service that can be provided on any particular railway line. The aims set when it comes to designing these systems to operate a railway line are: to ensure safety of operation and to ensure flexible and efficient running. When building a line capacity optimisation algorithm, it must reach a compromise solution between two parameters: minimise the interval between trains and keep journey time as low as possible. This paper aims to describe the algorithm developed between METRO DE MADRID and CITEF (Railway Technology Research Centre of the Universidad Politécnica de Madrid – UPM) that allows the capacity of an underground line equipped with ATP Distance To Go systems to be studied and optimised. This algorithm facilitates the tasks of signalling design and optimisation. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
966.
Liwen Zhang Lixia Wei Guoliang Zhang J. Th.MDe Hosson Yuanliang Xia Fugang Wang . The State Key Laboratory for Materials Modification by Laser Ion Electron Beams . Material Engineering Department of Dalian University of Technology Dalian 《上海交通大学学报(英文版)》2000,(1)
IntroductionLaserTransformationhardeningtechniquehasbeensuccessfullyusedinindustryformanyyears.AlotsoftheoreticalworkshasbeendoneforheatflowduringthelasertfansformationhardeningofflatworkPieces["].Cyindricalbodiesarewidelyusedinindustrysuchaslocomotivecrankshaft,steelrollervalyeseat,enginecyinder.IftheschcesoftheseworkPiecesaretreatedbylasertheirwearresistancewiIIimProvealot.UptillnowmanyexPerimentalworkshasbeendoneforlasertransformationhardeningofcyindricalbodies,butfewtheoreticalworkshav… 相似文献
967.
K. Jeon H. Hwang S. Choi J. Kim K. Jang K. Yi 《International Journal of Automotive Technology》2012,13(2):247-253
Cornering maneuvers with reduced body roll and without loss in comfort are leading requirements for car manufacturers. An
electric active roll control (ARC) system controls body roll angle with motor-driven actuators installed in the centers of
the front and rear stabilizer bars. A vehicle analysis model developed using a CarSim S/W was validated using vehicle test
data. Two ARC algorithms for a sports utility vehicle (SUV) were designed using a sliding-mode control algorithm based on
a nonlinear roll model and an estimated lateral acceleration based on a linearized roll model. Co-simulation with the Matlab
simulink controller model and the CarSim vehicle model were conducted to evaluate the performance of two ARC control algorithms.
To validate the ARC performance in a real vehicle, vehicle tests were conducted at KATECH proving ground using a small SUV
equipped with two ARC actuators, upper and lower controllers and a few subsystems. From the simulation and vehicle validation
test results, the proposed ARC control algorithm for the developed ARC actuator prototypes improves the vehicle’s dynamic
performance. 相似文献
968.
J. Wu 《International Journal of Automotive Technology》2012,13(3):409-422
This paper presents a robust optimization method to decrease the variations in the performance of the designed system caused
by the unavoidable manufacturing, installation or measurement errors of the design variables. Generally, it is difficult and
costly to determine statistical information with sufficient precision for uncertain design variables; in this study, interval
numbers are used to describe the uncertain design variables, and only the bounds of these variables are required. An improved
interval truncation method is presented for estimating the variation ranges of the system performances. The robustness estimations
of the system performances are incorporated into the optimization formulation to obtain the nominal design variables, which
could make the system performances relatively robust; therefore, the design robustness is estimated and improved in the optimization
iteration process. The robust optimization method is applied to a general powertrain mounting system (PMS) to improve the
design robustness of the PMS decoupling layout and frequency allocation. The optimization results show that the robust optimization
method could effectively increase the decoupling ratios in the interested vertical and pitch directions, and the frequency
allocation is more robust than that obtained using the traditional deterministic optimization. 相似文献
969.
Q. Fan J. Bian H. Lu L. Li J. Deng 《International Journal of Automotive Technology》2012,13(4):523-531
The first firing cycle is very important during cold-start for all types of spark ignition engines. In addition, the combustion characteristics of the first firing cycle affect combustion and emissions in the following cycles. However, the first-cycle fuel-air mixing, combustion and emissions generation within the cylinder of a two-stage direct-injection (TSDI) engine during cold start is not completely understood. Based on the total stoichiometric air-fuel ratio and local richer mixture startup strategy, the first-cycle firing and combustion characteristic at cold start were investigated in a two-stage direct injection (TSDI) gasoline engine. In addition, the effects of the first injection timing, second injection timing, 1st and 2nd fuel injection proportion and total excess air ratio on the in-cylinder pressure, heat release rate and accumulated heat release were analyzed on the basis of a cycle-by-cycle analysis. It is shown that a larger 2nd fuel injection amount and later 2nd injection timing are more beneficial to the firing of the first cycle in the case of a total excess air ratio of 1.0. The optimum 1st and 2nd injection timing fuel injection proportions are 120°CA ATDC during the intake stroke, 60°CA BTDC during the compression stroke and 1:1. In addition, the firing boundary is a 2nd injection timing later than 90°CA BTDC during the compression stroke in the case of the 1st injection timing from 60°CA to 180°CA ATDC during an intake stroke and involves a 1st and 2nd fuel injection proportion of 1:1 and an excess air ratio of 1.0. The study provides a detailed understanding of cold-start combustion characteristics and a guide for optimizing the reliable first-cycle firing at cold start. 相似文献
970.
To solve the power steering (PS) hose oil leakage problem in automobile applications, a new geometry design of the metal fitting is required, and the swaging conditions applied to the PS hose should be optimized. In this study, a new metal fitting geometry for the PS hose was proposed. A CAE simulation for both the proposed and the conventional metal fittings was conducted, and both the stress and the strain in the PS hose were compared. An experimental verification was also performed with these two different metal fittings. Additionally, the swaging conditions were optimized by the durability cycle time, which was measured in an impulse test of the swaged PS hose. For a more economical production, practical working conditions were also recommended and experimentally verified. 相似文献