In this paper we are concerned with the problem of inducing recursive Horn clauses from small sets of training examples. The method of iterative bootstrap induction is presented. In the first step, the system generates simple clauses, which can be regarded as properties of the required definition. Properties represent generalizations of the positive examples, simulating the effect of having lar...

Reed-Muller (RM) codes of growing length n and distance d are considered over a binary symmetric channel. A recursive decoding algorithm is designed that has complexity of order n log n and corrects most error patterns of weight (d ln d)/2. The presented algorithm outperforms other algorithms with nonexponential decoding complexity, which are known for RM codes. We evaluate code performance usi...

Turbo codes are usually constructed using systematic recursive convolutional codes (SRCC’s) as constituent codes. In this paper, we introduce a new class of turbo codes that uses nonsystematic recursive convolutional codes (NSRCC’s) as constituent codes. A systematic constituent code then becomes a particular case of this more general class. The use of this larger class of constituent codes enh...

We analyze a normalization function for the simply typed λ-calculus based on hereditary substitutions, a technique developed by Pfenning et al. The normalizer is implemented in Agda, a total language where all programs terminate. It requires no termination proof since it is structurally recursive which is recognized by Agda’s termination checker. Using Agda as an interactive theorem prover we e...

Dynamic programming is a powerful technique for efficiently solving recursive problems, but it’s hardly the end of the story. In many cases, once we have a basic dynamic programming algorithm in place, we can make further improvements to bring down the running time or the space usage. We saw one example in the Fibonacci number algorithm. Buried inside the naïve iterative Fibonacci algorithm is ...

A well known technique for speech enhancement is spectral subtraction. This technique is attractive due to its simplicity and its low computational cost. We have proposed a simple modi cation of the lter coe cient calculation in form of a recursion of the previous lter coe cient. Because of this recursion the subtraction rule (gain curve) consists of two di erent paths, one for increasing signa...

Program inversion is a fundamental problem that has been addressed in many different programming settings and applications. In the context of term rewriting, several methods already exist for computing the inverse of an injective function. These methods, however, usually return non-terminating inverted functions when the considered function is tail recursive. In this paper, we propose a direct ...

Contract languages such as JML and Spec# specify invariants and preand postconditions using side-effect free expressions of the programming language, in particular, pure methods. For such contracts to be meaningful, they must be well-formed: First, they must respect the partiality of operations, for instance, the preconditions of pure methods used in the contract. Second, they must enable a con...

The super-exponential algorithm is a block-based technique for blind channel equalization and system identi cation. Due to its fast convergence rate, and no a priori parameterization other than the block length, it is a useful tool for linear equalization of moderately distortive channels. This paper presents a recursive implementation of the super-exponential algorithm for fractionally-sampled...