Alberto Sangiovanni-Vincentelli

Bio: Alberto Sangiovanni-Vincentelli is an academic researcher from University of California, Berkeley. The author has contributed to research in topics: Logic synthesis & Finite-state machine. The author has an hindex of 99, co-authored 934 publications receiving 45201 citations. Previous affiliations of Alberto Sangiovanni-Vincentelli include National University of Singapore & Lawrence Berkeley National Laboratory.

Overcoming heterophobia: modeling concurrency in heterogeneous systems

Abstract: System level design is complex. One source of this complexity is that systems are often heterogeneous: different models of computation (e.g., dataflow, FSMs) are used to describe different components of a system. Existing formal methods for concurrent systems are typically based on one particular model of computation, so it is difficult to formalize the interaction between heterogeneous components. In this paper, we develop a framework for formalizing the relationships between different models of computation.

A case study in computer-aided codesign of embedded controllers

Abstract: With our codesign system, POLIS, we have specified and implemented a real-life design: a shock absorber controller. Through this experiment, we have shown the possibility of using such a system to design complex applications and to speed up the design cycle dramatically. All aspects of the design process are closely scrutinized including high level language translation and automatic hardware and software synthesis. We analyze different software implementation styles and draw some conclusions about our design process. >

Retiming of circuits with single phase transparent latches

Abstract: An algorithm is developed for the retiming of single phase sequential circuits with level sensitive (transparent) latches. A set of constraints that permit retiming and optimal clock cycle computation are also developed. It is shown that a design with edge-triggered latches may be tested for speed-up using transparent latches. >

Binary decision diagrams on network of workstations

Abstract: The success of all binary decision diagram (BDD) based synthesis and verification algorithms depend on the ability to efficiently manipulate very large BDDs. We present algorithms for manipulation of very large Binary Decision Diagrams (BDDs) on a network of workstations (NOW). A NOW provides a collection of main memories and disks which can be used effectively to create and manipulate very large BDDs. To make efficient use of memory resources of a Now, while completing execution in a reasonable amount of wall clock time, extension of breadth-first technique is used to manipulate BDDs. BDDs are partitioned such that nodes for a set of consecutive variables are assigned to the same workstation. We present experimental results to demonstrate the capability of such an approach and point towards the potential impact for manipulating very large BDDs.

Modeling micro-controller peripherals for high-level co-simulation and synthesis

Abstract: Luciano Lavagno, Claudio Passerone, and Claudio SansoePolitecnico di TorinoMapping a behavior on an embedded system involves hardware-software partitioning and assignment of software and hardware tasks to different components. In particular, software tasks in embedded controllers are mostly assigned to a micro-controller. However, some micro-controller peripherals are implemented with partly programmable components that can be regarded as very simple co-processors with limited instruction sets and capabilities. Embedded system designers are used to mapping some simple software tasks onto these simple co-processors, obtaining overall performances that can be orders of magnitude superior to the ones obtained mapping all software tasks to the micro-controller itself. In this paper, we propose a methodology to specify, simulate, and partition tasks that can be implemented on programmable micro-controller peripherals such as Timing Processing Units (TPUs). Following our general philosophy, we let the designer propose a partition, and we provide an environment to: - efficiently simulate and evaluate a particular implementation choice, - automate downstream synthesis for software, hardware, as well as peripheral programming routines.

Gradient-based learning applied to document recognition

Abstract: Multilayer neural networks trained with the back-propagation algorithm constitute the best example of a successful gradient based learning technique. Given an appropriate network architecture, gradient-based learning algorithms can be used to synthesize a complex decision surface that can classify high-dimensional patterns, such as handwritten characters, with minimal preprocessing. This paper reviews various methods applied to handwritten character recognition and compares them on a standard handwritten digit recognition task. Convolutional neural networks, which are specifically designed to deal with the variability of 2D shapes, are shown to outperform all other techniques. Real-life document recognition systems are composed of multiple modules including field extraction, segmentation recognition, and language modeling. A new learning paradigm, called graph transformer networks (GTN), allows such multimodule systems to be trained globally using gradient-based methods so as to minimize an overall performance measure. Two systems for online handwriting recognition are described. Experiments demonstrate the advantage of global training, and the flexibility of graph transformer networks. A graph transformer network for reading a bank cheque is also described. It uses convolutional neural network character recognizers combined with global training techniques to provide record accuracy on business and personal cheques. It is deployed commercially and reads several million cheques per day.

Differential Evolution – A Simple and Efficient Heuristic for Global Optimization over Continuous Spaces

Abstract: A new heuristic approach for minimizing possibly nonlinear and non-differentiable continuous space functions is presented. By means of an extensive testbed it is demonstrated that the new method converges faster and with more certainty than many other acclaimed global optimization methods. The new method requires few control variables, is robust, easy to use, and lends itself very well to parallel computation.

Phd by thesis

Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Graph-Based Algorithms for Boolean Function Manipulation

Abstract: In this paper we present a new data structure for representing Boolean functions and an associated set of manipulation algorithms. Functions are represented by directed, acyclic graphs in a manner similar to the representations introduced by Lee [1] and Akers [2], but with further restrictions on the ordering of decision variables in the graph. Although a function requires, in the worst case, a graph of size exponential in the number of arguments, many of the functions encountered in typical applications have a more reasonable representation. Our algorithms have time complexity proportional to the sizes of the graphs being operated on, and hence are quite efficient as long as the graphs do not grow too large. We present experimental results from applying these algorithms to problems in logic design verification that demonstrate the practicality of our approach.

Principles of Model Checking

Abstract: Our growing dependence on increasingly complex computer and software systems necessitates the development of formalisms, techniques, and tools for assessing functional properties of these systems. One such technique that has emerged in the last twenty years is model checking, which systematically (and automatically) checks whether a model of a given system satisfies a desired property such as deadlock freedom, invariants, and request-response properties. This automated technique for verification and debugging has developed into a mature and widely used approach with many applications. Principles of Model Checking offers a comprehensive introduction to model checking that is not only a text suitable for classroom use but also a valuable reference for researchers and practitioners in the field. The book begins with the basic principles for modeling concurrent and communicating systems, introduces different classes of properties (including safety and liveness), presents the notion of fairness, and provides automata-based algorithms for these properties. It introduces the temporal logics LTL and CTL, compares them, and covers algorithms for verifying these logics, discussing real-time systems as well as systems subject to random phenomena. Separate chapters treat such efficiency-improving techniques as abstraction and symbolic manipulation. The book includes an extensive set of examples (most of which run through several chapters) and a complete set of basic results accompanied by detailed proofs. Each chapter concludes with a summary, bibliographic notes, and an extensive list of exercises of both practical and theoretical nature.