Fingerprints are useful for biometric purposes because of their well known properties of distinctiveness and persistence over time. However, owing to skin conditions or incorrect finger pressure, original fingerprint images always contain noise. Especially, some of them contain useless components, which are often mistaken for the terminations that are an essential minutia of a fingerprint. Math...

Maximum flow is a fundamental problem in Combinatorial Optimization that has numerous applications in both theory and practice. In this paper, we study the flow network simplification problem, which asks to remove all the useless arcs from the graph. To be precise, an arc is useless if it does not participate in any simple s, t-path. Weihe [FOCS’94, JCSS’97] showed if there exists an O(n log n)...

When packet loss rate exceeds a given threshold, received audio and video become unintelligible. A congested router transmitting multimedia packets, while inflicting a packet loss rate beyond a given threshold, effectively transmits useless packets. Useless packet transmission wastes router bandwidth when it is needed most. We propose an algorithm to avoid transmission of useless multimedia pac...

We propose a preprocessing method for Web mining which, given semi-structured documents with the same structure and style, distinguishes useless parts and non-useless parts in each document without any knowledge on the documents. It is based on a simple idea that any n-gram is useless if it appears frequently. To decide an appropriate pair of length n and frequency a, we introduce a new statist...

Twig pattern matching plays a crucial role in XML data processing. TwigStack [2] is a holistic twig join algorithm that solves the problem in two steps: (1) finding potentially useful intermediate path solutions, (2) merging the intermediate solutions. The algorithm is optimal when the twig pattern has only //-edges, in the sense that no useless partial solutions are generated in the first step...