{ The bigraph crossing problem, embedding the two node sets of a bipartite graph G = (V0; V1; E) along two parallel lines so that edge crossings are minimized, has application to placement optimization for standard cells and other technologies. Iterative improvement heuristics involve repeated application of some transformation on an existing feasible solution to obtain better feasible solution...

In practical pattern recognition applications, the nearest neighbor classifier (NNC) is often applied because it does not require an a priori knowledge of the joint probability density of the input feature vectors. As the number of example vectors is increased, the error probability of the NNC approaches that of the Baysian classifier. However, at the same time, the computational complexity of ...

We describe a procedure which finds a hierarchical clustering by hillclimbing. The cost function we use is a hierarchical extension of the k-means cost; our local moves are tree restructurings and node reorderings. We show these can be accomplished efficiently, by exploiting special properties of squared Euclidean distances and by using techniques from scheduling and VLSI algorithms.

In fractal image compression, the code is given by a contractive aane mapping whose xed point is an approximation to the original image. Usually, the mapping is found by the collage coding method. We propose an algorithm that starts from an initial mapping obtained by collage coding and iteratively provides a sequence of contractive mappings whose xed points are monotonically approaching the or...

The paper presents two heuristics for hardwarelsoftware partitioning of system level spec@cations. The main objective is to achieve pedormance optimization with a limited hardware and software cost. We consider minimization of communication cost and improvement of the overall parallelism as essential criteria. One ofthe heuristics is based on simulated annealing and the other on tabu search. Ex...

X-ray grating interferometer can simultaneously retrieve attenuation, refraction, and scattering signals of the imaged sample, which shows its great potential in biomedical imaging. However, fast scan gratings high centrifugal forces during rotating grating-based cone-beam computed tomography (CBCT) system may lead to phase-stepping (PS) errors position fluctuations, cause reconstruction failur...

In this paper, we propose a new approach, parallel iterative improvement (PII), to solving the stable matching problem. This approach treats the stable matching problem as an optimization problem with all possible matchings forming its solution space. Since a stable matching always exists for any stable matching problem instance, finding a stable matching is equivalent to finding a matching wit...

In this work, the method of iterative Fourier transform phase reconstruction, conventionally used in holography and optical image reconstruction, is applied to phase only synthesis of antenna patterns. The method is applied to two types of pattern synthesis problems: "main lobe beam shaping" and "side-lobe-level reduction". The proposed method is most useful in the efficient employment of attai...