4 research outputs found
General Terms Theory
No full textThe complexity of algorithms tax even the resources of sixty billion gigabits--or of a universe full of bits; Meyer and Stockmeyer had proved, long ago, that, regardless of computer power, problems existed which could not be solved in the life of the universe
Relaxing the Triangle Inequality in Pattern Matching
No full text. Any notion of "closeness" in pattern matching should have the property that if A is close to B, and B is close to C, then A is close to C. Traditionally, this property is attained because of the triangle inequality (d(A; C) d(A; B) + d(B; C), where d represents a notion of distance). However, the full power of the triangle inequality is not needed for this property to hold. Instead, a "relaxed triangle inequality" suffices, of the form d(A; C) c(d(A; B) + d(B; C)), where c is a constant that is not too large. In this paper, we show that one of the measures used for distances between shapes in (an experimental version of) IBM's QBIC 1 ("Query by Image Content") system (Niblack et al., 1993) satisfies a relaxed triangle inequality, although it does not satisfy the triangle inequality. Keywords: pattern matching, shape matching, triangle inequality, distance measure, image database. 1 QBIC is a trademark of IBM Corporation. 1 Introduction Traditionally, databases have been used ..
Logic and Formal Languages]: Mathematical Logic—mechanical theorem proving
No full textAbstract. An exponential lower bound on the circuit complexity of deciding the weak monadic second-order theory of one successor (WS1S) is proved. Circuits are built from binary operations, or 2-input gates, which compute arbitrary Boolean functions. In particular, to decide the truth of logical formulas of length at most 610 in this second-order language requires a circuit containing at least 10 125 gates. So even if each gate were the size of a proton, the circuit would not fit in the known universe. This result and its proof, due to both authors, originally appeared in 1974 in the Ph.D. thesis of the first author. In this article, the proof is given, the result is put in historical perspective, and the result is extended to probabilistic circuits.
Open Access Publishing: A Literature Review
No full textWithin the context of the Centre for Copyright and New Business Models in the Creative Economy (CREATe) research scope, this literature review investigates the current trends, advantages, disadvantages, problems and solutions, opportunities and barriers in Open Access Publishing (OAP), and in particular Open Access (OA) academic publishing. This study is intended to scope and evaluate current theory and practice concerning models for OAP and engage with intellectual, legal and economic perspectives on OAP. It is also aimed at mapping the field of academic publishing in the UK and abroad, drawing specifically upon the experiences of CREATe industry partners as well as other initiatives such as SSRN, open source software, and Creative Commons. As a final critical goal, this scoping study will identify any meaningful gaps in the relevant literature with a view to developing further research questions. The results of this scoping exercise will then be presented to relevant industry and academic partners at a workshop intended to assist in further developing the critical research questions pertinent to OAP
