7274427
Low Power Synthesis Methodology with Data Format Optimization Applied on a DWT
In modern VLSI circuits, power consumption has become a design criteria as well as speed and silicon area or gate count. To guide the designer implementing complex applications with real time constraint on dedicated circuits, we present a High Level Synthesis methodology that provides a Register Transfer Level description of an ASIC, from a behavioral description of an algorithm; this complete methodology uses basic techniques such as selection, assignment or scheduling specified for power optimization, associated with a new approach based on data format optimization. Actually, instead of the usual 32-bit floating-point format, it is power efficient to use a fixed-point format provided overflow and computation noise problems are solved. The application of our method on an usual DSP example (the DWT) shows a power reduction of more than 60%.
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.
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.
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.
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%.
5821670
Learning in Logic with RichProlog
Deduction and induction are unified on the basis of a generalized notion of logical consequence, having classical first-order logic as a particular case. RichProlog is a natural extension of Prolog rooted in this generalized logic, in the same way as Prolog is rooted in classical logic. Prolog can answer ?1 queries as a side effect of a deductive inference. RichProlog can answer ?1 queries, ?1 queries (as a side effect of an inductive inference), and ?2 queries (as a side effect of an inductive inference followed by a deductive inference). RichProlog can be used to learn: a learning problem is expressed as a usual logic program, supplemented with data, and solved by asking a ?2 query. The output is correct in the limit, i.e., when sufficient data have been provided.
9681382
A Dialectic Approach to Problem-Solving
We analyze the dynamics of problem-solving in a framework which captures two key features of that activity. The first feature is that problem-solving is a social game where a number of problem-solvers interact, rely on other agents to tackle parts of a problem, and regularly communicate the outcomes of their investigations. The second feature is that problem-solving requires a careful control over the set of hypotheses that might be needed at various stages of the investigation for the problem to be solved; more particularly, that any incorrect hypothesis be eventually refuted in the face of some evidence: all agents can expect such evidence to be brought to their knowledge whenever it holds. Our presentation uses a very general form of logic programs, viewed as sets of rules that can be activated and fire, depending on what a problem-solver is willing to explore, what a problem-solver is willing to hypothesize, and what a problem-solver knows about the problem to be solved in the form of data or background knowledge. 
 
Our framework supports two fundamental aspects of problem-solving. The first aspect is that no matter how the work is being distributed amongst agents, exactly the same knowledge is guaranteed to be discovered eventually. The second aspect is that any group of agents (with at one end, one agent being in charge of all rules and at another end, one agent being in charge of one and only one rule) might need to sometimes put forward some hypotheses to allow for the discovery of a particular piece of knowledge in finite time.
31898263
Limiting Resolution: From Foundations to Implementation
We present a generalization of SLD-resolution, Limiting Resolution (LR) which embeds concepts from the field of inductive inference into logic programming. This paper describes the development of LR from theoretical underpinnings through to demonstrating a practical implementation. LR is designed to represent and solve problems which are not purely deductive more easily than current logic programming formalisms. It is based on the notion of identification in the limit, where successful computations produce a non-halting converging sequence of outputs as opposed to computations which produce a single output and halt. The queries of LR are of the form \(\exists \overline{x} ( \psi(\overline{x}) \land \forall \overline{y} \neg \chi(\overline{x},\overline{y}))\), with some restrictions on the occurrence of negation in ψ and χ. The programs are divided into background knowledge and a potentially infinite stream of data which drives the construction of the converging sequence of outputs. In some problems true negation can be applied to data in this stream. We describe the logical foundations of LR, where the notions of induction, deduction and identification in the limit are unified in a common framework. The programs, queries, and proof procedure of LR are precisely defined, and a completeness result is stated. Furthermore we present a Prolog-style system, RichProlog, which implements LR, and provide an extended example of RichProlog’s execution. This example shows that it is possible to solve genuine problems in polynomial time and also illustrates RichProlog’s utility, conciseness, and declarative nature.
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.
29056335
Learning power and language expressiveness
The topic of the present work is to study the relationship between the power of the learning algorithms on the one hand, and the expressive power of the logical language which is used to represent the problems to be learned on the other hand. The central question is whether enriching the language results in more learning power. In order to make the question relevant and nontrivial, it is required that both texts (sequences of data) and hypotheses (guesses) be translatable from the "rich" language into the "poor" one. The issue is considered for several logical languages suitable to describe structures whose domain is the set of natural numbers. It is shown that enriching the language does not give any advantage for those languages which define a monadic second-order language being decidable in the following sense: there is a fixed interpretation in the structure of natural numbers such that the set of sentences of this extended language true in that structure is decidable. But enriching the original language even by only one constant gives an advantage if this language contains a binary function symbol (which will be interpreted as addition). Furthermore, it is shown that behaviourally correct learning has exactly the same power as learning in the limit for those languages which define a monadic second-order language with the property given above, but has more power in case of languages containing a binary function symbol. Adding the natural requirement that the set of all structures to be learned is recursively enumerable, it is shown that it pays off to enrich the language of arithmetics for both finite learning and learning in the limit, but it does not pay off to enrich the language for behaviourally correct learning.