33073441
Synthèse Comportementale Sous Contraintes de Communication et de Placement Mémoire pour les composants du TDSI
The design of complex Digital Signal Processing systems implies to minimize architectural cost and to maximize timing performances while taking into account communication and memory accesses constraints for the integration of dedicated hardware accelerator. Unfortunately, the traditional Matlab/ Simulink design flows gather not very flexible hardware blocs. In this paper, we present a methodology and a tool that permit the High-Level Synthesis of DSP applications, under both I/O timing and memory constraints. Based on formal models and a generic architecture, our tool GAUT helps the designer in finding a reasonable trade-off between the circuit's performance and its architectural complexity. The efficiency of our approach is demonstrated on the case study of a FFT algorithm.
15834659
Architectural Synthesis with Interconnection Cost Control
Architectural synthesis tools map algorithms to architectures under various constraints and quickly provide estimations of area and performance. However, these tools do not take the interconnection cost into account whereas it becomes predominant with the technology decrease and the application complexity increase. A way to control costly interconnections during the architectural process is presented in this paper.
34309839
Design of a flexible 2-D discrete wavelet transform IP core for JPEG2000 image coding in embedded imaging systems
The increasingly demanding requirements of multimedia applications have led to the definition of complex image and video coding standards such as JPEG2000 and MPEG4. Implementation of image or video encoders or decoders on mobile device requires high integration densities together with ability for "real-time" (on-the-fly) data processing. Today, the electronic system design community is mainly concerned with defining efficient System-on-a-Chip (SoC) design methodologies in order to benefit from the high integration capabilities of current application-specific integrated circuit and field-programmable gate array technologies on the one hand, and manage the increasing algorithmic complexity of applications on the other hand. Intellectual property (IP) reuse is considered as the key to speed up the system design and verification flow and make it more reliable.In this context, we have introduced a novel methodology for VLSI implementation of computation-intensive algorithms targeting digital signal processing applications. Our methodology combines IP reuse and high-level synthesis (HLS) and introduces the notion of "Behavioral IP". This approach aims at leveraging IP re-usability through functional and architectural flexibility based on: (1) modeling a component's behavior at a high abstraction level and (2) benefiting from HLS tools for architectural exploration and hardware generation.In this paper, we illustrate our methodology in the case of a 2-D discrete wavelet transform IP core for JPEG2000 image compression. We describe the successive views of the component throughout the design flow, from the application level down to the architectural level. We also provide synthesis results showing the variety of dedicated architectures that can be generated depending on user-defined functional-level, system-level and architectural-level requirements. We compare the performance and re-usability of the set of obtained architectures versus hand-crafted RTL specifications.
11449422
Functional level power analysis: an efficient approach for modeling the power consumption of complex processors
A high-level consumption estimation methodology and its associated tool, SoftExplorer, are presented. The estimation methodology uses a functional modeling of the processor combined with a parametric model to allow the designer to estimate the power consumption when the embedded software is executed on the target. SoftExplorer uses as input the assembly code generated by the compiler; its efficiency is compared to SimplePower's approach. Results for different processors (TI C62, C67, C55, and ARM7) and for several DSP applications provide an average error less than 5%.
15462003
How to transform an architectural synthesis tool for low power VLSI designs
High level synthesis (HLS) for low power VLSI design is a complex optimization problem due to the area/time/power interdependence. As few low power design tools are available, a new approach providing a modular low power synthesis method is proposed. Although based for the moment on a generic architectural synthesis tool Gaut, the use of different "commercial" tools is possible. The Gaut-w HLS tool is constituted of low power modules: high level power dissipation estimation, assignment, module selection (operators and supply voltage), optimization criteria and operators library. As illustration, power saving factors on DWT algorithms are presented.
5563691
Synchronization processor synthesis for latency insensitive systems
In this paper we present our contribution in terms of synchronization processor for a SoC design methodology based on the theory of the latency insensitive systems (LIS) of Carloni et al. (2001). Our contribution consists in IP encapsulation into a new wrapper model whose speed and area are optimized and synthetizability guaranteed. The main benefit of our approach is to preserve the local IP performance when encapsulating them and reduce SoC silicon area.
7592429
On the Convergence of Incremental Knowledge Base Construction
Ripple Down Rules is a practical methodology to build knowledge-based systems, which has proved successful in a wide range of commercial applications. However, little work has been done on its theoretical foundations. In this paper, we formalise the key features of the method. We present the process of building a correct knowledge base as a discovery scenario involving a user, an expert, and a system. The user provides data for classification. The expert helps the system to build its knowledge base incrementally, using the output of the latter in response to the last datum provided by the user. In case the system’s output is not satisfactory, the expert guides the system to improve its future performance while not affecting its ability to properly classify past data. We examine under which conditions the sequence of knowledge bases constructed by the system eventually converges to a knowledge base that faithfully represents the target classification function. Our results are in accordance with the observed behaviour of real-life systems.
20226862
Foundations for a Formalism of Nearness
Reasoning about your spatial environment can be a challenging task, especially when you are a robot trying to rely solely on quantitative measures. With nearness being such a vague concept, a qualitative representation is an obvious choice offering a wider range of possible values.This paper introduces a qualitative representation for spatial proximity that accounts for absolute binary nearness relations. The formalism is based on the notion of perceived points, called sites, in a point based universe. Proximity concepts are determined by the parameters of distance between two sites and weight of each of those sites. These parameters were drawn from the concept of Generalised Voronoi Diagrams.Cognitively useful models and interpretations of our formalism are shown in both a navigation and a natural language context.
21797978
Input-Dependence in Function-Learning
In the standard model of inductive inference, a learner gets as input the graph of a function, and has to discover (in the limit) a program for the function. In this paper, we consider besides the graph also other modes of input such as the complement of the graph, the undergraph and the overgraph of the function. The relationships between these models are studied and a complete picture is obtained. Furthermore, these notions are also explored for learning with oracles, learning in teams and learning in the presence of additional information.
1859636
Autonomous capture of a tumbling satellite
In this paper, we describe a framework for the autonomous capture and servicing of satellites. The work is based on laboratory experiments that illustrate the autonomy and remote-operation aspects. The satellite-capture problem is representative of most on-orbit robotic manipulation tasks where the environment is known and structured, but it is dynamic since the satellite to be captured is in free flight. Bandwidth limitations and communication dropouts dominate the quality of the communication link. The satellite-servicing scenario is implemented on a robotic test-bed in laboratory settings
39068570
Learning, Logic, and Topology in a Common Framework
Many connections have been established between learning and logic, or learning and topology, or logic and topology. Still, the connections are not at the heart of these fields. Each of them is fairly independent of the others when attention is restricted to basic notions and main results. We show that connections can actually be made at a fundamental level, and result in a parametrized logic that needs topological notions for its early developments, and notions from learning theory for interpretation and applicability.One of the key properties of first-order logic is that the classical notion of logical consequence is compact. We generalize the notion of logical consequence, and we generalize compactness to s-weak compactness where s is an ordinal. The effect is to stratify the set of generalized logical consequences of a theory into levels, and levels into layers. Deduction corresponds to the lower layer of the first level above the underlying theory, learning with less than s mind changes to layer s of the first level, and learning in the limit to the first layer of the second level. Refinements of Borel-like hierarchies provide the topological tools needed to develop the framework.