We study efficient and exact shortest path algorithms for routing on road networks with realistic traffic data. For navigation applications, both current (i.e., live) traffic events and predictions of future traffic flows play an important role in routing. While preprocessing-based speedup techniques have been employed successfully to both settings individually, a combined model poses significant challenges. Supporting predicted traffic typically requires expensive preprocessing while live traffic requires fast updates for regular adjustments. We propose an A*-based solution to this problem. By generalizing A* potentials to time dependency, i.e. the estimate of the distance from a vertex to the target also depends on the time of day when the vertex is visited, we achieve significantly faster query times than previously possible. Our evaluation shows that our approach enables interactive query times on continental-sized road networks while allowing live traffic updates within a fraction of a minute. We achieve a speedup of at least two orders of magnitude over Dijkstra's algorithm and up to one order of magnitude over state-of-the-art time-independent A* potentials.

In this paper, we investigate the coding efficiency of perceptual coding using an adaptive non-uniform orthogonal filter-bank based on MDCT analysis/synthesis and time domain aliasing reduction. We compare its performance to a system using a traditional adaptive uniform MDCT filterbank with window switching. The comparison is performed using a listening test at two different quantization settings. The statistical evaluation shows that the percetpual quality of the nonuniform filterbank significantly out-performs that of the uniform filterbank by 5 to 10 MUSHRA points.

Time Domain Aliasing Reduction (TDAR) is a method to improve the impulse response compactness of non-uniform orthogonal Modified Discrete Cosine Transforms (MDCT). Previously, TDAR was only possible between frames of identical time-frequency tilings, however in this letter we describe a method to overcome this limitation. This method enables the use of TDAR between two consecutive frames of different time-frequency tilings by introducing another subband merging or subband splitting step. Consecutively, this method allows more flexible and adaptive filterbank tilings while retaining compact impulse responses, two attributes needed for efficient perceptual audio coding.

In this letter we describe nonuniform orthogonal modified discrete cosine transform (MDCT) filterbanks and time-domain aliasing reduction (TDAR). By adding a postprocessing step to the MDCT, our method allows for arbitrary nonuniform frequency resolutions using subband merging with smooth windowing and overlap in frequency. This overlap allows for an improved temporal compactness of the impulse response, which is especially useful for audio coders. The postprocessing step comprises another lapped MDCT transform along the frequency axis and TDAR along each subband signal.

The paper deals with a heuristical approach to compensate friction hysteresis in an aggregate actuator which is proposed to be applied in a camless engine system and which consists of piezoelectric, mechanic and hydraulic components. The hydraulic displacement amplifier shows a conspicuous hysteresis effect that appears to be a dead time that depends on the speed of the engine. In general, with high engine speeds, the dead time effect is reduced. The compensation of the hysteresis effect is not model-based since the real time application must run within a very short time. The presented approach consists of an adaptive pre-action on the desired servo piston trajectory which is generated by a feedforward action fed by phase-variable Gaussian curves as desired valve trajectories. Simulations show the effectiveness of the proposed compensating techniques.

In this paper a model of a hybrid actuator is proposed. It consists of a piezo-mechanical structure (including a hydraulic transmission ratio) and a hydraulic aggregate. Moreover, a cascade control strategy based on Model Predictive Control (MPC) is proposed to track periodic valve trajectory signals. The proposed cascade control structure consists of an internal and an external controller. The secondary, internal controller is needed to accomplish a Soft Landing. The MPCs are combined with two feed forward control actions, one for each part of the model. Simulation results carried out the suitability of the control approach.

A hybrid actuator composed by a piezo and a hydraulic part and with a Switching Model Predictive Control (SMPC) structure for camless engine motor applications are described in this paper. The Preisach dynamic model with a hysteresis effect is considered. Hysteresis phenomena are often present in technical systems and processes and this represents a challenging issue for their control. The approach presented in this paper is quite general and can be applied also in many other systems and processes. Simulations with real data are shown.

This paper deals with a hybrid actuator composed by a piezo and a hydraulic part and with a cascade PID-PID control structure for camless engine motor applications. The idea is to use the advantages of both, the high precision of the piezo and the force of the hydraulic part. In fact, piezoelectric actuators (PEAs) are commonly used for precision positionings, despite PEAs present nonlinearities, such as hysteresis, saturations, and creep. In the control problem such nonlinearities must be taken into account. In this paper the Preisach dynamic model with the above mentioned nonlinearities is considered together with cascade PID-PID controllers combined with a feed-forward action. In particular, the hysteresis effect is considered and a model with a switching function is used also for the controller design. Simulations with real data are shown.