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811.
A. Rahman A. K. M. Mohiuddin A. Hossain 《International Journal of Automotive Technology》2011,12(4):503-512
To improve crossing ability, the most important performance factor for tracked vehicle systems operating on low-bearing capacity
peats, and to minimize income losses that result from downtime and maintenance costs, a vehicle was designed in order to adapt
to operating condition changes. This article describes the mobile performance of a novel vehicle with segmented rubber tracks
on a low-bearing capacity peat. At an equivalent travelling speed, the novel vehicle’s tractive performance in a variable
operating environment caused by changes in terrain cohesiveness and hydrodynamic responses was superior to that of the previous
model. The new vehicle, which could be operated on the Sepang peat, showed a tractive effort of 42.2% of the gross vehicle
weight in field experiments; the recommended minimum tractive effort is between 30 and 36% of the gross vehicle weight. 相似文献
812.
M. J. L. Boada B. L. Boada D. Garcia-Pozuelo V. Diaz 《International Journal of Automotive Technology》2011,12(6):821-829
The behaviour of the tyre plays an important role in the vehicle handling. An accurate tyre model that estimates these forces
and moments it is highly essential for the studies of vehicle behaviour. For the last ten years neural networks have attracted
a great deal of attention in vehicle dynamics and control. Neural networks have been effectively applied to model complex
systems due to their good learning capability. In this paper a recursive lazy learning method based on neural networks is
considered to model the tyre characteristics under combined braking and cornering. The proposed method is validated by comparison
with experimental obtained responses. Results show the estimated model correlates very well with the data obtained experimentally.
Moreover, the neural model proposed allows to include the asymetric tyre behaviour in the tyre model without difficulty. 相似文献
813.
M. H. Lee H. M. Lee K. S. Lee S. K. Ha J. I. Bae J. H. Park H. G. Park H. J. Choi H. H. Chun 《International Journal of Automotive Technology》2011,12(5):733-744
In this paper, a hardware-in-the-loop simulation (HILS) system was developed before the development of an electric power steering
(EPS) system in a vehicle. This study was focused on the establishment of the HILS system. Driving conditions are simulated
with the HILS system. The actual steering input parameters are confirmed on the monitor while driving the HILS system. The
steering forces observed in the simulation with the developed HILS system are similar to those in real vehicle tests. The
developed HILS system can be applied in the development of various types of EPS systems. 相似文献
814.
In this paper, an optimized control strategy is proposed for a split parallel hydraulic hybrid truck. The model of the vehicle was simulated in Simulink. According to a global optimization technique, a fuzzy control strategy is developed for the vehicle. This strategy shows flexibility for different drive cycles and a desirable fuel consumption reduction, especially for a low speed drive cycle, which is extracted according to an urban utility vehicle mission. 相似文献
815.
M. M. Da Silva R. H. Cunha A. C. Neto 《International Journal of Automotive Technology》2012,13(6):915-922
In the field of vehicle dynamics, commercial software can aid the designer during the conceptual and detailed design phases. Simulations using these tools can quickly provide specific design metrics, such as yaw and lateral velocity, for standard maneuvers. However, it remains challenging to correlate these metrics with empirical quantities that depend on many external parameters and design specifications. This scenario is the case with tire wear, which depends on the frictional work developed by the tire-road contact. In this study, an approach is proposed to estimate the tire-road friction during steady-state longitudinal and cornering maneuvers. Using this approach, a qualitative formula for tire wear evaluation is developed, and conceptual design analyses of cornering maneuvers are performed using simplified vehicle models. The influence of some design parameters such as cornering stiffness, the distance between the axles, and the steer angle ratio between the steering axles for vehicles with two steering axles is evaluated. The proposed methodology allows the designer to predict tire wear using simplified vehicle models during the conceptual design phase. 相似文献
816.
In this study, a combined system consisting of a heat pump and a PTC heater was developed as a heating unit in electric vehicles. The system consists of a compressor, a condenser, an evaporator, an expansion device and a PTC heater. Experiments were conducted to examine the steady-state performance and dynamic characteristics of this system. The compressor speed, outdoor air inlet temperature, and indoor air inlet temperature were varied, and the performance of the system was experimentally investigated. The heating capacity, compressor power consumption and COP were obtained. Warm-up experiments were performed to investigate the dynamic characteristics of the system with a heat load of 1.5 kW in the indoor chamber. For the heat pump system, the PTC heater and the combined system, the heating performance and efficiency were investigated to determine an optimal control method. The results of this study agree well with the experimental results available in literature. This study provides experimental data of good quality for heating system design and the development of electric vehicles. 相似文献
817.
In lean-DeNOX catalysis reactions, hydrogen is a good reducing agent in PGM catalysts as well as an effective promoter in
selective catalytic reduction reactions over base metal oxide catalysts. However, such a lean-DeNOX system, which uses hydrogen,
requires an on-board fuel reforming system applicable to internal combustion engines. In this study, catalytic partial oxidation
(CPOx) performance was tested in a laboratory for various reactants and hydrocarbon conditions. Volume concentrations of 5–10%
oxygen and 0-5% water vapor were used to simulate diesel exhaust, and n-C12H26 was used as the feedstock for the reforming reaction. In the CPOx of n-C12H26, the highest hydrogen selectivity was 64% and was achieved at 100,000 h-1 GHSV. Additionally, the C/O ratio was less than
unity in the absence of water vapor. However, as the water concentration was increased to 2.5 and 5.0 vol. % in the n-C12H26 CPOx reactions, the maximum hydrogen selectivity was increased from 64% in the absence of water to 70% and 75%, respectively.
This effect is a consequence of the water-gas shift reaction over the catalyst bed. Regarding oxygen concentration effects,
hydrogen selectivity slightly increased with increasing oxygen concentration from 10% to 15%. It was also found that the CPOx
reaction of n-C12H26 can be ignited at temperatures below 300 C. Accordingly, it can be concluded that CPOx is a useful and feasible device for
promoting diesel DeNOx catalysis in terms of hydrogen productivity and reaction initiation. 相似文献
818.
M. A. Eltantawie 《International Journal of Automotive Technology》2012,13(3):423-431
In this paper, a decentralized neuro-fuzzy controller has been created in order to improve the ride comfort and increase the
stability for half car suspension system, which used the magneto-rheological damper as a semi-active device. Firstly, relative
gain array and relative disturbance gain methods have been used for deriving a relation between inputs, disturbances and outputs
to select pairing with minimum interaction to design a decentralize controller. Secondary, decentralized neuro-fuzzy controllers
for front and rear chassis are designed to predict the required damping force taking the acceleration of the sprung mass and
desired acceleration obtained by using pole-placement method as inputs. To predict the control voltage required for producing
the force predicted by the controller, the inverse neuro-fuzzy model of MR damper has been designed. Simulation by using MATLAB
programs has been created. The results show that the ride comforts and vehicle stability have been improved in comparison
with the passive system. 相似文献
819.
A fuzzy model was presented to predict the weldment shape profile of submerged arc welds(SAW) including the shape of heat affected zone(HAZ).The SAW bead-on-plates were welded by following a full factorial design matrix.The design matrix consisted of three levels of input welding process parameters.The welds were cross-sectioned and etched,and the zones were measured.A mapping technique was used to measure the various segments of the weld zones.These mapped zones were used to build a fuzzy logic model.The membership functions of the fuzzy model were chosen for the accurate prediction of the weld zone.The fuzzy model was further tested for a set of test case data.The weld zone predicted by the fuzzy logic model was compared with the experimentally obtained shape profiles and close agreement between the two was noted.The mapping technique developed for the weld zones and the fuzzy logic model can be used for on-line control of the SAW process.From the SAW fuzzy logic model an estimation of the fusion and HAZ can also be developed. 相似文献
820.
This article studies the liabilities of a multimodal transport operator under Chinese law. The present legal framework governing the multimodal transport consists of a complex array of laws and regulations. As a consequence, the applicable liability rules, the degree and the extent of the liability of a multimodal transport operator may vary from case to case. In addition, the ratification of the Rotterdam Rules would only contribute to clarification of legal complexities in a multimodal transport case where a sea leg is included. We conclude that there is a need to have a Chinese multimodal transport law which is broad enough in scope to govern the rights and liabilities of all parties involved in multimodal carriage in China. 相似文献