TY - JOUR AB - For almost three decades, the theory of visual attention (TVA) has been successful in mathematically describing and explaining a wide variety of phenomena in visual selection and recognition with high quantitative precision. Interestingly, the influence of feature contrast on attention has been included in TVA only recently, although it has been extensively studied outside the TVA framework. The present approach further develops this extension of TVA’s scope by measuring and modeling salience. An empirical measure of salience is achieved by linking different (orientation and luminance) contrasts to a TVA parameter. In the modeling part, the function relating feature contrasts to salience is described mathematically and tested against alternatives by Bayesian model comparison. This model comparison reveals that the power function is an appropriate model of salience growth in the dimensions of orientation and luminance contrast. Furthermore, if contrasts from the two dimensions are comb AU - Krüger, Alexander AU - Tünnermann, Jan AU - Scharlau, Ingrid ID - 6075 IS - 6 JF - Attention, Perception, & Psychophysics KW - Salience KW - Visual attention KW - Bayesian inference KW - Theory of visual attention KW - Computational modeling KW - Inference KW - Object Recognition KW - Theories KW - Visual Perception KW - Visual Attention KW - Luminance KW - Perceptual Orientation KW - Statistical Probability KW - Stimulus Salience KW - Computational Modeling SN - 1943-3921 TI - Measuring and modeling salience with the theory of visual attention. VL - 79 ER - TY - JOUR AB - Particular differences between an object and its surrounding cause salience, guide attention, and improve performance in various tasks. While much research has been dedicated to identifying which feature dimensions contribute to salience, much less regard has been paid to the quantitative strength of the salience caused by feature differences. Only a few studies systematically related salience effects to a common salience measure, and they are partly outdated in the light of new findings on the time course of salience effects. We propose Bundesen’s Theory of Visual Attention (TV A) as a theoretical basis for measuring salience and introduce an empirical and modeling approach to link this theory to data retrieved from temporal-order judgments. With this procedure, TV A becomes applicable to a broad range of salience-related stimulus material. Three experiments with orientation pop-out displays demonstrate the feasibility of the method. A 4th experiment substantiates its applicability t AU - Krüger, Alexander AU - Tünnermann, Jan AU - Scharlau, Ingrid ID - 6071 IS - 1 JF - Advances in Cognitive Psychology KW - salience KW - visual attention KW - Bayesian inference KW - theory of visual attention KW - computational modeling KW - Visual Attention KW - Computational Modeling KW - Inference KW - Judgment KW - Statistical Probability SN - 1895-1171 TI - Fast and conspicuous? Quantifying salience with the theory of visual attention. VL - 12 ER - TY - JOUR AB - In this contribution we present a theoretical and experimental investigation into the effects of reverberation and noise on features in the logarithmic mel power spectral domain, an intermediate stage in the computation of the mel frequency cepstral coefficients, prevalent in automatic speech recognition (ASR). Gaining insight into the complex interaction between clean speech, noise, and noisy reverberant speech features is essential for any ASR system to be robust against noise and reverberation present in distant microphone input signals. The findings are gathered in a probabilistic formulation of an observation model which may be used in model-based feature compensation schemes. The proposed observation model extends previous models in three major directions: First, the contribution of additive background noise to the observation error is explicitly taken into account. Second, an energy compensation constant is introduced which ensures an unbiased estimate of the reverberant speech features, and, third, a recursive variant of the observation model is developed resulting in reduced computational complexity when used in model-based feature compensation. The experimental section is used to evaluate the accuracy of the model and to describe how its parameters can be determined from test data. AU - Leutnant, Volker AU - Krueger, Alexander AU - Haeb-Umbach, Reinhold ID - 11861 IS - 1 JF - IEEE/ACM Transactions on Audio, Speech, and Language Processing KW - computational complexity KW - reverberation KW - speech recognition KW - automatic speech recognition KW - background noise KW - clean speech KW - computational complexity KW - energy compensation KW - logarithmic mel power spectral domain KW - mel frequency cepstral coefficients KW - microphone input signals KW - model-based feature compensation schemes KW - noisy reverberant speech automatic recognition KW - noisy reverberant speech features KW - reverberation KW - Atmospheric modeling KW - Computational modeling KW - Noise KW - Noise measurement KW - Reverberation KW - Speech KW - Vectors KW - Model-based feature compensation KW - observation model for reverberant and noisy speech KW - recursive observation model KW - robust automatic speech recognition SN - 2329-9290 TI - A New Observation Model in the Logarithmic Mel Power Spectral Domain for the Automatic Recognition of Noisy Reverberant Speech VL - 22 ER - TY - CONF AB - This paper presents an advanced eight levels spanning SystemC based virtual platform methodology and framework - referred to as HeroeS 3 - providing smooth application to platform mapping and continuous co-refinement of a virtual prototype with its physical environment model. For heterogeneity support, various SystemC extensions are combined covering continuous/discrete models of computation and different communication abstractions, such as analog mixed-signal models, abstract RTOS/HAL/middleware models, TLM bus models, and QEMU wrappers. We enable dependability assessment by Fault Effect Modeling (FEM) at the virtual prototype in order to avoid risking physical injury or damage. Also, simulation results are deterministic and can be evaluated interactively or offline. We apply FEM to both the physical environment model and the different abstractions of the virtual prototype. Currently, we focus on sensor failures and application control flow errors. AU - Becker, Markus AU - Kuznik, Christoph AU - Müller, Wolfgang ID - 36918 KW - Computational modeling KW - Finite element analysis KW - Prototypes KW - Abstracts KW - Software KW - Fault tolerance KW - Fault tolerant systems TI - Fault Effect Modeling in a Heterogeneous SystemC Based Virtual Platform Framework for Cyber Physical Systems ER - TY - CONF AB - Piezoelectric inertia motors use the inertia of a body to drive it by means of a friction contact in a series of small steps. These motors can operate in ``stick-slip'' or ``slip-slip'' mode, with the fundamental frequency of the driving signal ranging from several Hertz to more than 100 kHz. To predict the motor characteristics, a Coulomb friction model is sufficient in many cases, but numerical simulation requires microscopic time steps. This contribution proposes a much faster simulation technique using one evaluation per period of the excitation signal. The proposed technique produces results very close to those of timestep simulation for ultrasonics inertia motors and allows direct determination of the steady-state velocity of an inertia motor from the motion profile of the driving part. Thus it is a useful simulation technique which can be applied in both analysis and design of inertia motors, especially for parameter studies and optimisation. AU - Hunstig, Matthias AU - Hemsel, Tobias AU - Sextro, Walter ID - 9784 KW - friction KW - ultrasonic motors KW - Coulomb friction model KW - efficient simulation technique KW - friction contact KW - high-frequency piezoelectric inertia motor KW - motor characteristics prediction KW - numerical simulation KW - slip-slip mode KW - stick-slip mode KW - time-step simulation KW - ultrasonic inertia motor KW - Acceleration KW - Acoustics KW - Actuators KW - Computational modeling KW - Friction KW - Numerical models KW - Steady-state SN - 1948-5719 T2 - Ultrasonics Symposium (IUS), 2012 IEEE International TI - An efficient simulation technique for high-frequency piezoelectric inertia motors ER - TY - CONF AB - Many heterogeneous embedded systems, for example industrial automation and automotive applications, require hard-real time constraints to be exhaustively verified - which is a challenging task for the verification engineer. To cope with complexity, verification techniques working on different abstraction levels are best practice. SystemC is a versatile C++ based design and verification language, offering various mechanisms and constructs required for embedded systems modeling. Using the add-on SystemC Verification Library (SCV) elemental constrained-random stimuli techniques may be used for verification. However, SCV has several drawbacks such as lack of functional coverage. In this paper we present a functional coverage library that implements parts of the IEEE 1800-2005 SystemVerilog standard and allows capturing functional coverage throughout the design and verification process with SystemC. Moreover, we will demonstrate the usability of the approach with a case study working on a CAN bus model written in SystemC. AU - Defo, Gilles B. AU - Müller, Wolfgang AU - Kuznik, Christoph ID - 37057 KW - Libraries KW - Generators KW - Transfer functions KW - Monitoring KW - Computational modeling KW - Driver circuits KW - Adaptation model T2 - Proceedings of SIES 2010 TI - Verification of a CAN Bus Model in SystemC with Functional Coverage ER - TY - CONF AB - We present a rigorous but transparent semantics definition of SystemC that covers method, thread, and clocked thread behavior as well as their interaction with the simulation kernel process. The semantics includes watching statements, signal assignment, and wait statements as they are introduced in SystemC V1.O. We present our definition in form of distributed Abstract State Machines (ASMs) rules reflecting the view given in the SystemC User's Manual and the reference implementation. We mainly see our formal semantics as a concise, unambiguous, high-level specification for SystemC-based implementations and for standardization. Additionally, it can be used as a sound basis to investigate SystemC interoperability with Verilog and VHDL. AU - Müller, Wolfgang AU - Ruf, Jürgen AU - Hoffmann, D. W. AU - Gerlach, Joachim AU - Kropf, Thomas AU - Rosenstiehl, W. ID - 39421 KW - Yarn KW - Formal verification KW - Kernel KW - Hardware design languages KW - Electronic design automation and methodology KW - Algebra KW - Computational modeling KW - Logic functions KW - Computer languages KW - Clocks SN - 0-7695-0993-2 T2 - Proceedings of the Design, Automation, and Test in Europe (DATE’01) TI - The Simulation Semantics of SystemC ER -