In this paper we present a novel distance measure, the minimum landscape distance (MLD). MLD provides a non-linear mapping between the elements in one sequence to those of another. Each element in one sequence is mapped to that with the highest neighbourhood structural similarity (landscape) in the other sequence within a search window. Experimental results obtained on sequences representing binary images show that MLD is superior to the Euclidean, correlation, and dynamic time warping (DTW) distance measures. We experimented with various sequence, landscape, and search window sizes.

In this paper, we present a novel approach to shape representation and description based on the combination of the Hilbert space filling curve and wavelet analysis. Our objective is to capitalize on the localization-preserving nature of the Hilbert space filling curve and the approximation power of the wavelet transform. The object image is scanned using the Hilbert curve and the resulting vector is smoothed using the wavelet transform and sampled. The technique is O(N) for both representation and comparison. We present some experimental results on the MPEG-7 dataset, Kimia-99 dataset, ETH-80 dataset, and a logo dataset.

Summary form only given. Location tracking systems are discrete in nature location information about each moving object (MO) is sampled at certain points in time. To determine the location of a MO between location reports or sometime in the future, we have to estimate the location at that point in time using the location reports we already have. The sampling frequency could affect the system's estimation accuracy as well as operating costs. Poor estimation accuracy could also carry a cost. The objective is to maximize the estimation accuracy while minimizing the operating cost. In this paper, we introduce the novel idea of using user modeling to improve the estimation accuracy of both the route and speed of a MO without the need to increase the sampling rate. We focus on a subset of moving objects we call roving users, or RUs for short. A RU is a human or human-controlled MO. The idea is that humans are creatures of habit. Knowing how a RU behaved in the past could help us estimate what he/she will do in the future. This knowledge could help us estimate the user location more accurately.

In this paper a barcode-based system to help the visually impaired identity objects in the environment and navigate through unknown territories is introduced. The system is based on the idea of tagging the different objects with 2D barcodes. With the aid of a portable camera and a computing device, the system can recognize and relay the barcode content to the user. We present the advantages of the proposed system compared to those of existing technologies. The different steps for recognizing and extracting the barcodes are described and applied to a sample image.

A new layout method, Prime-groups, is proposed to evenly distribute parity groups for declustered RAID. Prime-groups satisfies most of the layout goals for a good declustered RAID layout. For the goals that are not satisfied, it is near optimal. A new layout goal maximal write and reconstruction parallelism is also proposed. If a layout satisfies the new goal, all the surviving disks can be read in parallel and can be rewritten in parallel during reconstruction and reconfiguration. Prime-groups satisfies the new goal when the write request begins in the first disk of the array. It is also near optimal in term of declustering ratio when p is a prime. Prime-groups can compliment the layouts proposed by G.A. Alvarez et. al. (1996), as the criteria to obtain a good layout is quite different between Prime-groups and those proposed by Alvarez et. al.

We propose a new n-dimensional fault-tolerant hypercube architecture. We use (n-1) switching networks to connect the N=2/sup n/ active processors and k spare processors to form an n-dimensional fault-tolerant hypercube. The k spare processors can be used to back-up any k processor failures in the fault-tolerant hypercube. We call such a method global sparing and it is optimal in terms of the number of processor failures that can be back-up by k spare processors. The new architecture can achieve a higher level of reliability using less hardware compared to previously proposed schemes.

We introduce a new family of interconnection networks that are Cayley graphs with fixed degrees of any even number greater than or equal to four. We call the proposed graphs cyclic-cubes because contracting some cycles in such a graph results in a generalized hypercube. These Cayley graphs have optimal fault tolerance and logarithmic diameters. For comparable number of nodes, a cyclic-cube can have a diameter smaller than previously known fixed-degree networks. The proposed graphs can adopt an optimum routing algorithm known for one of its subfamilies of Cayley graphs. We also show that a graph in the new family has a Hamiltonian cycle and, hence, there is an embedding of a ring. Embedding of meshes and hypercubes are also discussed.

When a data file is replicated at more than one site, we are interested in detecting corruption by comparing the multiple copies. In order to reduce the amount of messaging for large files, techniques based on page signatures and combined signatures have been explored. However, for 3 or more sites, the known methods assume that the number of corrupted page copies to be at most [M/2]-1, where M is the number of sites. We point out that this assumption is unrealistic and the corresponding methods are unnecessarily pessimistic. In this paper, we replace this assumption by another assumption which we show to be reasonable. Based on this assumption, we derived a distributed algorithm which in general achieves better performance than previously known results. Our system model is also more refined than previous work.

The magic rewriting focuses on relevant data but suffers from additional rules, predicates, and tuples that are generated in search for the relevant data. Reducing the arity of predicates can cut down the number of such rules, predicates, and tuples by an exponential factor. In this paper, we consider a subclass of linear single-IDB programs and show that the magic rewriting can be decomposed in such a way that it is applied to only programs having smaller arities and fewer recursive rules, without losing the binding capacity. The decomposed rewriting is shown to be much more efficient than the standard one and amenable to distributed and parallel environments. The considered subclass significantly generalizes recursions previously proposed for efficient implementation. The decomposed rewriting and the standard generalized magic rewriting are extended to multi-binding queries in such a way that data relevant to one binding is not necessarily considered as relevant to other bindings. The work in this paper shows the use of tuple ID as an important technique in optimizing logic programs.

Parallel bottom-up evaluation provides an alternative for the efficient evaluation of logic programs. Existing parallel evaluation strategies are neither effective nor efficient in determining the data to be transmitted among processors. In this paper, we propose re different strategy, for general Datalog programs, that is based on the partitioning of data rather than that of rule instantiations. The partition and processing schemes defined in this paper are more general than those in existing strategies. A parallel evaluation algorithm is given based on the semi-naive bottom-up evaluation. A notion of potential usefulness is recognized as a data transmission criterion to reduce, both effectively and efficiently, the amount of data transmitted. Heuristics and algorithms are proposed for designing the partition and processing schemes for a given program. Results from an experiment show that the strategy proposed in this paper has many promising features.>