Harman (Germany)

To push the right information to the right person at the right time, classical work on recommendation systems focuses on optimizing the rating of recommended items. Recent research on context-awareness and knowledge exchange shows potentials of recommendation systems in engineering work. Requirements engineering can also profit from recommendation systems in several scenarios, including maintaining requirements, sharing collaboration information and reusing templates. By describing these scenarios and identifying key realization challenges, this paper presents a vision on recommendation systems in requirements engineering.

A novel semi-analytical signal processing model for the binaural coherence of homogeneous isotropic noise fields is presented in this contribution. This is derived from a simplified geometrical model of the human head, where the shadowing between the left and right ear is modeled by two nonreflecting circular plates. Based on Kirchhoff's diffraction theory, it is shown how the corresponding coherence is calculated. This model can be used as part of various binaural signal processing algorithms, such as speech enhancement for digital hearing aids or binaural speech transmission systems. In experiments using an artificial head in a highly reverberant environment, it is confirmed that the proposed theoretical model shows a good match with the coherence obtained from measurements.

Due to the rising ecological awareness as well as the scarcity of fuel, associated with the rising price of petrol, the demand for economically ideal working vehicles rose. Car manufacturers put a lot of effort in improving the car body, the engine, or the power train of cars. However, the driver can save fuel and money by learning a more efficient driving style, too. Assistance systems can help drivers to learn a more economic driving style and drive anticipating. In this paper an Anticipatory Energy Saving Assistant (ANESA <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> ) is presented. It is helping the driver to drive anticipating and, thus, driving more energy efficient. For this purpose, ANESA is giving the driver precisely timed commands regarding the velocity restrictions upcoming. By approaching a velocity restriction freewheeling, the energy loss of braking is avoided. The advices of ANESA are based on the freewheeling characteristic of the car, given the current speed and the elevation profile of the track ahead, and the upcoming velocity restrictions, which can be road signs or sharp turns. Evaluations in a Driving Simulator showed, that drivers saved 12.97% of energy in average using ANESA by the more usage of 2.53% of time. The tests showed as well, that using ANESA drivers saved 8.06% more energy than trying to save energy by their own abilities.

Modern engineering and scientific optimisation problems are becoming complicated. In order to cope with the increasing level of difficulty of these problems, optimisation methods are required to find more than one solution to these problems. The aim of this paper is to gain an insight into the ability of cuckoo search to locate more than one solution for multimodal problems. We also study the performance of this algorithm in the additive white Gaussian noise. Numerical results are presented to show that the cuckoo search algorithm can successfully locate multiple solutions in both non-noise and additive white Gaussian noise with relatively high degree of accuracy.

The quote from Pierre Boulez, given as an epigraph to this article, inspired French researchers to start developing technology for spherical loudspeaker arrays in the 1990s. The hope was to retain the naturalness of sound sources. Now, a few decades later, one might be able to show that even more can be done: In electroacoustic music, using the icosahedral loudspeaker array called IKO seems to enable spatial gestures that enrich alien sounds with a tangible acoustic naturalness. After a brief discussion of directivity-based composition in computer music, the first part of the article describes the technical background of the IKO, its usage in a digital audio workstation, and psychoacoustic evidence regarding the auditory objects the IKO produces. The second part deals with acoustic equations of spherical beamforming, how the IKO's loudspeakers are controlled correspondingly, how we deal with excursion limits, and the resulting beam patterns generated by the IKO.

Tracking of lanes is essential for intelligent vehicles in order to drive autonomously. A system is presented which allows tracking of multiple lanes. The system is based on a clear modelling of a lane and the parameter set of each lane is estimated using a particle filter which fuses different cues. A finite-state machine then decides whether or not a lane is really tracked. For each lane, a separate tracker is used and a set of rules controls the life-cycle of all trackers and keeps track of all the estimated lanes

Extending commercial tools for variability management is the problem addressed in this paper. IBM Rational DOORS is a well accepted tool in the area of requirements engineering and supports an Application Programming Interface (API) called DOORS extension Language (DXL). In this contribution we present a way of extending DOORS for product line requirements engineering based on a DXL plug-in called metadoc feature modeler. Established concepts in the community such as feature diagrams, instantiation of feature models, automatic deficit analysis and issue-based variability are introduced into DOORS. These concepts are abstracted using the DOORS meta-model. As DOORS is directly extended using new components, no special synchronizers are required between feature modeling environment and DOORS (which is a difference with respect to traditional feature modeling tools). We share our experience in using the feature modeler at a medium-sized company.

Supplementary traffic signs are used to alter the meaning of other traffic signs. Assistance systems that recognize traffic signs therefore must also recognize supplementary signs to evaluate their influence on the meaning of detected traffic signs. We propose an algorithm which is able to detect supplementary signs in the vicinity of other signs using a novel rectangle segmentation algorithm. Support vector machines are used for the classification and rejection of other objects. The combination of both components permits to recognize a supplementary sign in less than 40 ms. First quantitative results for a test set with four different supplementary sign types show a very good classification accuracy of more than 96%.

The cross-ambiguity function (CAF) is commonly used to analyze the delay-Doppler characteristics of signals in radar, sonar, and communication systems. Accordingly, a CAF relates to the correlation processing of signals in the presence of delays and Doppler shifts. In this paper, we use a metaheuristic approach to address the CAF synthesis problem by jointly designing a pair of waveforms. The CAF ofwaveforms designed in this way, approximates a desired pre-defined CAF. It turns out that the waveforms designed by this approach have the benefit of low peak-to-average power ratios. Numerical examples are presented to show that nature-inspired metaheuristic algorithms can be used as an effective tool to synthesize different types of CAFs.

In hands-free telephony and other distant-talk applications, often a short AEC filter is used to achieve fast convergence at low computational cost. As a result, a significant amount of late residual echo (LRE) may remain, especially in highly reverberant environments. This LRE can be suppressed using a postfilter in the subband domain, which requires an estimate of the power spectral density (PSD) of the LRE. To estimate the LRE PSD, an exponentially decaying model with frequency-dependent reverberation scaling and decay parameters has frequently been assumed. State-of-the-art methods estimate both reverberation parameters independently of each other, either in offline or in online mode. In this article, we propose two signal-based methods (i.e. output error and equation error) to jointly estimate both reverberation parameters in online mode. The estimated parameters are then used to generate an estimate for the LRE PSD, which is fed into a postfilter for the purpose of late residual echo suppression. We derive several gradient-descent-based algorithms to simultaneously update both reverberation parameters, minimizing either the mean squared error or the mean squared log error cost function. The proposed methods are compared with state-of-the-art methods in terms of the accuracy of the estimated reverberation parameters and the corresponding LRE PSD estimate. Extensive simulation results using both artificial as well as measured room impulse responses show that the proposed output error method with mean squared log error minimization outperforms state-of-the-art methods in all considered scenarios.

Compact microphone arrays allow for directional filtering with a minimum of installation space. They are therefore particularly suitable for automotive applications. Typically, compact arrays are realized as differential arrays or filter-and-sum beamformers which both show limited performance in terms of directivity. In this contribution we present a novel system for directional filtering for compact arrays. This system consists of two closely spaced microphones and incorporates an adaptive beamformer as well as a spatial post-filter which is designed to suppress non-stationary noise.

A system architecture is proposed which enables information, communication and entertainment applications in cars, based on optical networking. Video and audio signals are transmitted as MPEG bitstreams. DVD and TV can be viewed on multiple color LCD screens.

Most switched mode power supplies provide a regulated voltage at their output. However, there are applications requiring a controlled current. Among others are battery chargers, test equipment for converters driven by solar cells, and LED drivers. This paper describes a dc-dc power converter realizing such a current source. The converter is based on a boost converter, supplied by a voltage source and acting as a current source. The boost converter can increase the output voltage above the input voltage. The converter provides a high control bandwidth based on a self-oscillating current loop. As additional practical features, soft start and output overvoltage limitation are included and described in this paper. The modulator, the control, and the power stage are described in detail and verified by the experiment.

We present a new approach for residual transient noise suppression at the output of an arbitrary beamformer. A spatial optimum estimate for the instantaneous a posteriori SNR is derived on the basis of the output signals of a blocking matrix. The optimization problem is formulated in the logarithmic domain and statistical models for the obtained quantities are given. Based on these models the optimization problem is solved in the maximum a posteriori sense. It is shown that the performance of speech recognition systems in non-stationary noise scenarios is improved considerably compared to the performance achieved with a Wiener filter applied to the beamformer output.

Variability management of a product family is the core aspect of Software Product Line Engineering. The adoption of this mature approach requires a high upfront investment before being able to automatically generate product instances based on customer requirements. However, this adoption costs and risks could be reduced with an incremental approach, which mines existing assets and then transitions to full product line engineering. Those existing assets can be for instance similar product variants that were implemented using ad-hoc reuse techniques such as clone-and-own. Bottom-up approaches to automatically extract variability management related artifacts could be proposed, applied, validated and improved in this domain therefore the REVE workshop aims to fill the gap between the Reengineering and Software Product Line Engineering communities.

AuszugWenn von Landespolitik in Deutschland die Rede ist, dann spielt neben den Landesparlamenten und den Landesregierungen die jeweilige Staatskanzlei eine (häufig) so gewichtige Rolle, dass es gerechtfertigt erscheint, den Staatskanzleien einen eigenen Beitrag zu widmen.

In this work we present the preliminary results of the fusion of photonic mixer device - PMD and CMOS cameras for driver assistance applications. Although the algorithms are demonstrated mainly for pedestrians, they apply to the other objects on the street. PMD camera delivers the 3D object list. Object coordinates are further projected into CMOS image plane where classification is performed using support vector machines. As compared to PMD camera the CMOS camera has higher resolution, which gives the possibility to realize finer object detection, separation and classification. As the feature vector we use quadruple haar discrete wavelet transformation (QH DWT). The speed improvement of the SVM in the testing phase (necessary for real-time implementation) is realized with Burgpsilas reduced set vector method (BRSVM), improving classification speed nearly 70 times. We have achieved the pedestrian detection rate of 80%.

Summary form only given. MOST is a successful network solution for infotainment systems in cars. It provides an efficient synchronous network for streaming data as well as for asynchronous packet data with low administrative overhead. MOST25-systems (25 Mbit/s) using an optical physical layer and MOST50 (50Mbit/s) using electrical transmission are now widely spread in the automotive world. New audio and video applications in cars force the implementation of new high speed infotainment networks. This gave rise to the new 150 Mbit/s version of the MOST network, MOST 150. This paper highlights possible applications and features of the newly specified MOST150, such as an isochronous transport mechanism to support video applications, and the "Ethernet channel" for efficient transport of IP-based packet data. The first Physical Layer Specification for MOST150 defines an optical solution, which allows carmakers to speed up their existing MOST25-networks and to continue in using POF in the wire harness and LEDs as light sources. They can go on with their established optical wire harness and assembly processes which make the transition to higher bandwidth infotainment networks with MOST 150 a smooth evolution. A new approach of the MOST150 Physical Layer Specification was to define standardized packages together with pin-out descriptions for optoelectronic converters additionally to the electrical and optical signal parameters. The standardization of packages addresses the development of optical components, compatible with modern electronic-production processes. It reduces the supply chain and simplifies the handling of multiple supplysources for such optical components on TIER1-level. Based on lessons-learned of today's MOST25 optical modules, this paper describes the motivation for combining transmitter and receiver into a transceiver-design and choosing an SMD -package. Pro and Cons will be discussed as well as the capability of this new package concept to serve for other data rates and emitter/receiver technologies. Daimler AG , together with other premium manufactures, is working in the MOST Cooperation to specify a suited data bus for high speed infotainment networks. Since 2006 the Daimler AG is investigating the MOST150 optical data bus for usage in automobile environments. In the course of the year 2009 the decision about a series introduction of 150 Mbps MOST within Daimler cars is expected.

A software product line oriented approach to developing systems has an impact on the development process as a whole. Although the basic idea of product lines is simple, systematic implementation of the approach is a challenging task. In fact, today's software product lines have such complex variability that their handling must be supported by tools, otherwise a systematic approach would not be possible. The same holds for requirements management of product lines. On the basis of specific industrial scenarios the paper derives important requirements that have to be observed if requirements management tools are to be usefully applied to product lines. Current requirements management tools are evaluated on the basis of these requirements in their daily industrial use. The presented requirements can indicate the future direction of tool development and method research.

Requirements are identified and elaborated on the basis of stakeholders' decisions. The reasoning behind those decisions can be expressed as rationales. Systematic rationale management offers both short-term benefits, such as clearer requirements leading to fewer defects, and long-term benefits, such as simplified requirements evolution. However, little guidance exists for managing requirements rationales. This article presents guidelines to pragmatically capture, trace, maintain, and reuse such rationales. A list of questions augments the guidelines, improving their usability.