Interconnect delay has become a critical factor in determining the performance of integrated circuits. Routing and buffering are powerful approaches to improve circuit speed and correct timing violations after global ...
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ISBN:
(纸本)0769514413
Interconnect delay has become a critical factor in determining the performance of integrated circuits. Routing and buffering are powerful approaches to improve circuit speed and correct timing violations after global placement. this paper presents a dynamic-programming based algorithm for performing net topology construction and buffer insertion and sizing simultaneously under the given buffer-placement blockages. the differences from some previous works are that (1) the buffer locations are not pre-determined, (2) the multi-pin nets are easily handled, and (3) a line-search routing algorithm is implemented to speed up the process. Heuristics are used to reduce the problem complexity, which include limiting number of intermediate solutions, using a continuous buffer sizing model, and restricting the buffer locations along the Hanan graph. the resulting algorithm, named BRBP, was applied to a number of industrial designs and achieved an average of 7.9% delay improvement compared to a conventional design flow.
Multi-stage programming languages provide a convenient notation for explicitly staging programs. Staging a definitional interpreter for a domain specific language is one way of deriving an implementation that is both ...
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Multi-stage programming languages provide a convenient notation for explicitly staging programs. Staging a definitional interpreter for a domain specific language is one way of deriving an implementation that is both readable and efficient. In an untyped setting, staging an interpreter "removes a complete layer of interpretive overhead", just like partial evaluation. In a typed setting however, Hindley-Milner type systems do not allow us to exploit typing information in the language being interpreted. In practice, this can mean a slowdown cost by a factor of three or more. Previously, both type specialization and tag elimination were applied to this problem. In this paper we propose an alternative approach, namely, expressing the definitional interpreter in a dependently typed programming language. We report on our experience withthe issues that arise in writing such an interpreter and in designing such a language. To demonstrate the soundness of combining staging and dependent types in a general sense, we formalize our language (called Meta-D) and prove its type safety. To formalize Meta-D, we extend Shao, Saha, Trifonov and Papaspyrou's lambdaH language to a multi-level setting. Building on X,H allows us to demonstrate type safety in a setting where the type language contains all the calculus of inductive constructions, but without having to repeat the work needed for establishing the soundness of that system.
the kinematic constraints on a car limits the movements that it can follow, and this difficulty also makes planning a path a challenging problem. More precisely, the parallel parking problem has been widely addressed ...
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ISBN:
(纸本)9810474806
the kinematic constraints on a car limits the movements that it can follow, and this difficulty also makes planning a path a challenging problem. More precisely, the parallel parking problem has been widely addressed in the literature, but these approaches rely on more traditional methods using control laws, motion planners or artificial intelligence. there have been recently much interest in the robotics domain on using probabilistic approaches. In this paper, we propose an original formulation and resolution of the parking problem using Bayesian Robot programming.
the design and implementation of distributed real-time dependable systems is often dominated by non-functional considerations like timeliness, object placement and fault tolerance. In this paper we illustrate how aspe...
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ISBN:
(纸本)0769515762
the design and implementation of distributed real-time dependable systems is often dominated by non-functional considerations like timeliness, object placement and fault tolerance. In this paper we illustrate how aspect-oriented programming can be used to address the non-functional aspects of such system separately from the functional requirements and what benefits results from this separation of concerns. Besides the theoretical reflection we also present a case study in which distribution, timeliness, and fault tolerance aspects are added to a simple logging component. the examples are implemented using the emerging AspectC++ language for aspect-oriented programming with C++. In the course of this paper we also evaluated how well the general-purpose aspect language AspectC++ is suited to address the aspects specific to this domain.
Satisfiability of complex word-level formulas often arises as a problem in formal verification of hardware designs described at the register transfer level (RTL). Even though most designs are described in a hardware d...
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ISBN:
(纸本)0769514413
Satisfiability of complex word-level formulas often arises as a problem in formal verification of hardware designs described at the register transfer level (RTL). Even though most designs are described in a hardware description language (HDL), like Verilog or VHDL, usually, this problem is solved in the Boolean domain, using Boolean solvers. these engines often show a poor performance for data path verification. Instead of solving the problem at the bit-level, a method is proposed to transform conjunctions of bitvector equalities and inequalities into sets of integer linear arithmetic constraints. It is shown that it is possible to correctly model the modulo semantics of HDL operators as linear constraints. Integer linear constraint solvers are used as a decision procedure for bitvector arithmetic. In the implementation we focus on verification of arithmetic properties of Verilog-HDL designs. Experimental results show considerable performance advantages over high-end Boolean SAT solver approaches. the speed-up on the benchmarks studied is several orders of magnitude.
Quasi-periodicity and non-periodicity signal models are proposed. Each hypothetical one-quasiperiodical signal segment is considered as a random distortion of previous or following one taken withthe unknown multiplyi...
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Quasi-periodicity and non-periodicity signal models are proposed. Each hypothetical one-quasiperiodical signal segment is considered as a random distortion of previous or following one taken withthe unknown multiplying factor. the problem of optimal current pitch period discrimination and speech signal partition into one-quasiperiodical microsegments consists in the finding of the best one-quasiperiod beginnings or the onequasiperiodical segments under restrictions on both value and changing of current quasiperiod duration and multiplying factor. For this problem solving an effective algorithm based on dynamic programming is proposed and its application for speech signal analysis, recognition and synthesis is discussed.
Cooperative robotic systems provide design and implementation challenges that are not easy to solve. this paper describes a parallel implementation for evolving cooperative robotic behaviour using an island model base...
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ISBN:
(纸本)9810483643
Cooperative robotic systems provide design and implementation challenges that are not easy to solve. this paper describes a parallel implementation for evolving cooperative robotic behaviour using an island model based genetic program on a cluster computer system. the application domain is robot soccer in which two robots must cooperate to avoid collisions with each other and score goals. the system has access to robot and ball positions and outputs velocity set points for the robot wheel motors. the evolved controllers are evaluated on a kinematic model that has been optimised to improve the time complexity of the genetic programming algorithm. the inter-process communication on the cluster is implemented using the message passing interface (MPI).
this paper is related to a software for the design of shields to protect bio-objects from incident electric fields, magnetic fields,plane waves and ESD. An optimization is also taken in between required shielding effe...
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ISBN:
(纸本)0780375637
this paper is related to a software for the design of shields to protect bio-objects from incident electric fields, magnetic fields,plane waves and ESD. An optimization is also taken in between required shielding effectiveness and weight carrying capacity by using dynamic programming method.
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