Hybrid Vehicles introduce new technologies and new challenges into automotive design. Although these new technologies promise to gain greater efficiencies, they are not as proven as conventional drivetrain systems. Co...
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ISBN:
(纸本)0863416098
Hybrid Vehicles introduce new technologies and new challenges into automotive design. Although these new technologies promise to gain greater efficiencies, they are not as proven as conventional drivetrain systems. Companies and their engineers cannot rely on the know-how of their existing systems for this new evolving technology. Specifically the interaction between the different drive concepts and the complex control algorithm is a big challenge in the development of a hybrid vehicle. Virtual design and the use of advanced simulation methods like statistical analysis and FMEA are therefore more important than ever to reduce the design risk. This presentation will examine the benefits of virtual design and robust design techniques, used extensively in the development process of traditional vehicles, applied to the challenges of drivetrain systems in hybrid vehicles.
The typical engineering design process can be decomposed into several phases: creative exploration of ideas, testing soundness of proposed concepts, refining concepts to realizable solutions, optimizing viable solutio...
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ISBN:
(纸本)0769524737
The typical engineering design process can be decomposed into several phases: creative exploration of ideas, testing soundness of proposed concepts, refining concepts to realizable solutions, optimizing viable solutions with respect to performance/cost. Powerful computer algorithms have been developed for many of these tasks. Often these modules are rigid allowing for little intervention by the designer, and the management of the interactions of these tasks mostly relies on human intelligence. Better user interfaces are required to integrate more fully human ingenuity and the assistance of the computer into the overall design process. The most powerful CAD systems should combine the power of programming, graphical visualization, and interactive adjustment of crucial design parameters.
In this paper we will present a nonlinear-model-based adaptive semiactive control algorithm developed for magnetorheological (MR) suspension systems exposed to broadband nonstationary random vibration sources that are...
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In this paper we will present a nonlinear-model-based adaptive semiactive control algorithm developed for magnetorheological (MR) suspension systems exposed to broadband nonstationary random vibration sources that are assumed to be unknown or not measurable. If there exist unknown and/or varying parameters of the dynamic system such as mass and stiffness, then the adaptive algorithm can include on-line system identification such as a recursive least-squares method. Based on a nonparametric MR damper model, the adaptive system stability is proved by converting the hysteresis inherent with MR dampers to a memoryless nonlinearity with sector conditions. The convergence of the adaptive system, however is investigated through a linearization approach including further numerical, illustration of specific cases. Finally the simulation results for a magnetorheological seat suspension system with the suggested adaptive control are presented. The results are compared with low-damping and high-damping cases, and such comparison further shows the effectiveness of the proposed nonlinear model-based adaptive control algorithm for damping timing.
An output control for tracking the command signal front linear parametrically uncertain systems under external disturbances is studied. The control scheme is simple in realization and of small size, which distinguish ...
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An output control for tracking the command signal front linear parametrically uncertain systems under external disturbances is studied. The control scheme is simple in realization and of small size, which distinguish it from other known analogs. A numerical example is given to illustrate the performance of the control algorithm.
System capacity is the paramount requirement in the design of code division multiple access (CDMA) cellular systems. Power control to mobiles is an essential tool used to maximise the system capacity by minimising int...
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System capacity is the paramount requirement in the design of code division multiple access (CDMA) cellular systems. Power control to mobiles is an essential tool used to maximise the system capacity by minimising interference while at the same time maintaining transmission quality. The convergence speed of power control algorithm is critical in determining its practical application especially when the propagation and traffic condition are rapidly changing. In this letter, a new centralised power control algorithm is proposed to solve the power control problem by using symmetric successive overrelaxation (SSOR) preconditioned generalised product-type bi-conjugate gradient (GPBi-CG) iteration method. The simulation results show that our proposed algorithm has much faster convergent rate than the distributive constrained second-order power control (CSOPC) and constrained Gauss-Seidel (CGS) algorithm. The fast convergent speed can increase the overall network capacity. Copyright (c) 2005 AEIT.
The article focuses on the Java-Hosted Algorithm Visualization Environment (JHAVÉ), which fosters the use of algorithm visualization as an effective pedagogical tool for computer science educators. Students attem...
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The article focuses on the Java-Hosted Algorithm Visualization Environment (JHAVÉ), which fosters the use of algorithm visualization as an effective pedagogical tool for computer science educators. Students attempting to learn the algorithm were often mystified by the high-powered display they saw unfolding in front of them. Developers of algorithm visualizations and the systems that facilitate them had too often show- cased their work to professionals who already understood the algorithm rather than the intended audience of students trying to learn it. Members of an Innovation and Technology in computer Science Education working group on improving the educational impact of algorithm visualization produced a report codifying-in an engagement taxonomy-modes that students could become active participants in exploring an algorithm with an algorithm visualization system. In the responding category, educators focus on having students answer questions concerning the visualization that the system presents. In the constructing category, students construct their own visualizations of the algorithm under consideration. This entails a larger time commitment on the part of the student. A common technique for constructing visualization is to first code it and then annotate it with calls to have graphics produced at interesting events during the algorithm's execution.
We introduce a technique to rapidly generate summed-area tables using graphics hardware. Summed area tables, originally introduced by Crow, provide a way to filter arbitrarily large rectangular regions of an image in ...
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We introduce a technique to rapidly generate summed-area tables using graphics hardware. Summed area tables, originally introduced by Crow, provide a way to filter arbitrarily large rectangular regions of an image in a constant amount of time. Our algorithm for generating summed-area tables, similar to a technique used in scientific computing called recursive doubling, allows the generation of a summed-area table in O(log n) time. We also describe a technique to mitigate the precision requirements of summed-area tables. The ability to calculate and use summed-area tables at interactive rates enables numerous interesting rendering effects. We present several possible applications. First, the use of summed-area tables allows real-time rendering of interactive, glossy environmental reflections. Second, we present glossy planar reflections with varying blurriness dependent on a reflected object's distance to the reflector. Third, we show a technique that uses a summed-area table to render glossy transparent objects. The final application demonstrates an interactive depth-of-field effect using summed-area tables.
A self-stabilizing algorithm cannot detect by itself that stabilization has been reached. For overcoming this drawback Lin and Simon introduced the notion of an external observer, i.e., a set of processes, one being l...
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A self-stabilizing algorithm cannot detect by itself that stabilization has been reached. For overcoming this drawback Lin and Simon introduced the notion of an external observer, i.e., a set of processes, one being located at each node, whose role is to detect stabilization. We propose here a less expensive approach, where there is a single observing process located at a unique node. This process is not allowed to detect false stabilization and it must eventually detect that stabilization is reached. Moreover it must not interfere with the observed self-stabilizing algorithm. Our result is that there exists such an observer for any problem on a distinguished network having a synchronous self-stabilizing solution. Note that our proof is constructive.
We describe a variant of TCP, called FAST, that can sustain high throughput and utilization at multigigabits per second over large distances. We present the motivation, review the background theory, summarize key feat...
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We describe a variant of TCP, called FAST, that can sustain high throughput and utilization at multigigabits per second over large distances. We present the motivation, review the background theory, summarize key features of FAST TCP, and report our first experimental results.
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