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991.
Ever increasing demand for the petroleum is causing faster than expected oil shortages in the supply and demand balance around
the world and furthermore, many specialists in the field of oil production such as Association for the Study of Peak Oil and
World Energy Outlook are claiming that the petroleum is around the peak of its production (Figure 1). Such shortage made the
greatest impact on the gasoline price hikes at the gas pump and thus, this impact was felt by the consumers severely and became
the greatest motivation for automotive industries to strive to pioneer the researches for the next generation vehicle configurations
ranging from HEV, PHEV, Pure EV to FCHEV (collectively noted as xEV). While the great deal of researches has been carried
over the last few decades, it is still far from mass productions for consumer use except for the HEV mainly due to the high
cost involved with other types of xEV configurations. Therefore, it is critical to design the vehicle to maximize the use
of each component at its highest point regardless of any cost scenarios and it is clear that this optimization can only be
achieved through the accurate energy balance simulation for a specific target vehicle prior to the actual hardware implementation.
In this paper, it is our intention to introduce modified dynamic battery modeling scheme that would provide a more accurate
way of simulating the battery behavior when used in the vehicle energy simulation system. Starting from a typical battery
dynamic model to predict the voltage given an imposed current request, we have introduced a new scheme to establish the relationship
between the voltage and the power (rather than the current) requested by the vehicle simulation system. The proposed scheme
handles the power request from the vehicle simulator considering the dynamic battery characteristics and in turn, contributes
to the better estimation of the current integrated energy usage and battery SOC level in the given battery dynamic system
used in the vehicle energy simulation system. 相似文献
992.
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
993.
J. -K. Kim E. S. Yim C. H. Jeon C. -S. Jung B. H. Han 《International Journal of Automotive Technology》2012,13(2):293-300
This study examines the cold performance of biodiesel blends in a passenger car and a light duty truck at −16 °C and −20 °C.
Six different types of biodiesels derived from soybean oil, waste cooking oil, rapeseed oil, cottonseed oil, palm oil and
jatropha oil were blended with different volume ratios (B5 (5 vol. % biodiesel — 95 vol. % diesel), B10 and B20). The cold
filter plugging point (CFPP) and the cloud point had an effect on the startability and driveability of both the passenger
car and the light duty truck. The startability and driveability of the passenger car with all biodiesel blends (B5) were generally
good at −20 °C. In the light duty truck, biodiesel blends (B10 and B20) of soybean, waste cooking, rapeseed and jatropha tended
to be good at −20 °C in the startability and driveability tests than the biodiesel blends (B10 and B20) of cottonseed and
palm. In particular, the palm biodiesel blend (B10) failed at −20 °C, and the palm biodiesel blend (B20) also failed at −16
°C in the startability test. The cold flow properties of biodiesel dictate that the length of the hydrocarbon chains and the
presence of unsaturated structures significantly affect the low temperature properties of biodiesel. 相似文献
994.
C. H. Zheng Y. I. Park W. S. Lim S. W. Cha 《International Journal of Automotive Technology》2012,13(3):517-522
The fuel economy of a fuel cell hybrid vehicle (FCHV) depends on its power management strategy because the strategy determines
the power split between the power sources. Several types of power management strategies have been developed to improve the
fuel economy of FCHVs. This paper proposes an optimal control scheme based on the Minimum Principle. This optimal control
provides the necessary optimality conditions that minimize the fuel consumption and optimize the power distribution between
the fuel cell system (FCS) and the battery during driving. In this optimal control, the final battery state of charge (SOC)
and the fuel consumption have an approximately proportional relationship. This relationship is expressed by a linear line,
and this line is defined as the optimal line in this research. The optimal lines for different vehicle masses and different
driving cycles are obtained and compared. This research presents a new method of fuel economy evaluation. The fuel economy
of other power management strategies can be evaluated based on the optimal lines. A rule-based power management strategy is
introduced, and its fuel economy is evaluated by the optimal line. 相似文献
995.
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
996.
David H. Weir 《国际交通安全学会研究报告》2010,34(1):16-21
The use of a driving simulator in the development of human-machine-interfaces (HMI) such as a navigation, information or entertainment system is discussed. Such use addresses the need to study and evaluate the characteristics of a candidate HMI early in the R&D and design stage to ensure that it is likely to meet various objectives and requirements, and to revise the HMI as may be necessary. Those HMI requirements include such things as usability, driver comfort, and an acceptable level of attentional demand in dual task conditions (driving while using an HMI). Typically, such an HMI involves an information display to the driver, and a means for driver input to the HMI. Corresponding simulator requirements are discussed, along with typical simulator features and components. The latter include a cab, control feel systems, visual image generator, real time scenario control (task definitions), a motion system (if provided), and data acquisition. Both fixed and moving base systems are described, together with associated benefits and tradeoffs. Considerations in the design of the evaluation experiment are discussed, including definition of primary and secondary tasks, and number of driver subjects (experimental participants). Possible response and performance measures for the primary and secondary tasks are noted, together with subjective measures such as task difficulty and ease of using the HMI. The advantages of using a driving simulator to support R&D are summarized. Some typical and example simulator uses are noted. 相似文献
997.
We investigated the effects of the fuel injection timing — both for early and late injection — in conjunction with the throttle
opening ratio on the fuel-air mixing characteristics, engine power, combustion stability and emission characteristics of a
DI CNG spark engine and control system that had been modified and designed according to the author’s original idea. We verified
that the combustion characteristics were affected by the fuel injection timing and that the engine conditions were affected
by the throttle opening ratios and the rpm. The combustion characteristics were greatly improved for a complete open throttle
ratio with an early injection timing and for a partial throttle ratio with a late injection timing. The combustion duration
was governed by the duration of flame propagation in late injection timing scenarios and by the duration of early flame development
in cases of early injection timing. As the result, the combustion duration is shortened, the lean limit is improved, the air-fuel
mixing conditions are controlled, and the emissions are reduced through control of the fuel injection timing and vary according
to ratio of the throttle opening. 相似文献
998.
The overall driving environment consists of the Traffic environment, vehicle and driver states (TVD). advanced driver assistance
Systems (ADAS) must consider not only information on each of the TVD states but also their context. Recent research has focused
on making more efficient and effective assistance systems by fusing all the information from the TVD states. Based on this
research trend, this paper focuses on decision-level fusion to estimate the level of danger of a warning by using visual information
of the traffic environment and the driver state. The driver state consists of the gazing region and the facial feature points
that are obtained using the active appearance model (AAM). The traffic environment state consists of time to collision (TTC),
time to lane Crossing (TLC), and lane color information, which are obtained from the environment in front of the vehicle,
i.e., position of lanes and other vehicles. Warnings against lane-off, collision, and driver inattention are generated by
fusing this vision-based information from inside and outside the vehicle. The experimental results prove that our vision-based
interactive driver assistance system reduces most useless warnings. 相似文献
999.
B. Suh A. Frank Y. J. Chung E. Y. Lee Y. H. Chang S. B. Han 《International Journal of Automotive Technology》2010,11(4):555-563
This research is the first to develop a design for a powertain system of a plug-in parallel diesel hybrid electric bus equipped
with a continuously variable transmission (CVT) and presents a new design paradigm of the plug-in hybrid electric bus (HEB).
The criteria and method for selecting and sizing powertrain components equipped in the plug-in HEB are presented. The plug-in
HEB is designed to overcome the vulnerable limitations of driving range and performance of a purely electric vehicle (EV)
and to improve fuel economy and exhaust emissions of conventional bus and conventional HEBs. The control strategy of the complicated
connected propulsion system in the plug-in parallel HEB is one of the most significant factors in achieving higher fuel economy
and lower exhaust emissions of the HEV. In this research, a new optimal control strategy concept is proposed against existing
rule-based control strategies. The optimal powertrain control strategy is obtained through two steps of optimizations: tradeoff
optimization for emission control and energy flow optimization based on the instantaneous optimization technique. The proposed
powertrain control strategy has the flexibility to adapt to battery SOC, exhaust emission amount, classified driving pattern,
driving condition, and engine temperature. The objective of the optimal control strategy is to optimize the fuel consumption,
electricity use, and exhaust emissions proper to the performance targets. The proposed control strategy was simulated to prove
its validity by using analysis simulation tool ADVISOR (advanced vehicle simulator). 相似文献
1000.
As driver assistant systems (DAS) and active safety vehicles (ASV) with various functions become popular, it is not uncommon
for multiple systems to be installed on a vehicle. If each function uses its own sensors and processing unit, it will make
installation difficult and raise the cost of the vehicle. As a countermeasure, research integrating multiple functions into
a single system has been pursued and is expected to make installation easier, decrease power consumption, and reduce vehicle
pricing. This paper proposes a novel side/rear safety system using only one scanning laser radar, which is installed in the
rear corner of the driver’s side. Our proposed system, ISRSS (integrated side/rear safety system), integrates and implements
four system functions: BSD (blind spot detection), RCWS (rear collision warning system), semi-automatic perpendicular parking,
and semi-automatic parallel parking. BSD and RCWS, which operate while the vehicle is running, share a common signal processing
result. The target position designation for perpendicular parking and parallel parking situations is based on the same signal
processing. Furthermore, as system functions during running and those during automatic parking operate in exclusive situations,
they can share common sensors and processing units efficiently. BSD and RCWS system functions were proved with 13025 and 2319
frames, respectively. The target position designation for perpendicular and parallel parking situations was evaluated with
112 and 52 situations and shows a success rate of 98.2% and 92.3%, respectively. 相似文献