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NASA Scientific and Technical Aerospace Reports

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A common obstacle preventing the rapid deployment of supervised machine learning algorithms is the lack of labeled<br />

training data. This is particularly expensive to obtain for structured prediction tasks, where each training instance may have<br />

multiple, interacting labels, all of which must be correctly annotated for the instance to be of use to the learner. Traditional<br />

active learning addresses this problem by optimizing the order in which the examples are labeled to increase learning<br />

efficiency. However, this approach does not consider the difficulty of labeling each example, which can vary widely in<br />

structured prediction tasks. For example, the labeling predicted by a partially trained system may be easier to correct for some<br />

instances than for others. We propose a new active learning paradigm which reduces not only how many instances the<br />

annotator must label, but also how difficult each instance is to annotate. The system also leverages information from partially<br />

correct predictions to efficiently solicit annotations from the user. We validate this active learning framework in an interactive<br />

information extraction system, reducing the total number of annotation actions by 22%.<br />

DTIC<br />

Machine Learning; Algorithms<br />

67<br />

THEORETICAL MATHEMATICS<br />

Includes algebra, functional analysis, geometry, topology, set theory, group theory <strong>and</strong> number theory.<br />

20060000046 Helsinki Univ. of Technology, Helsinki, Finl<strong>and</strong><br />

Quasihyperbolic Geodesics <strong>and</strong> Uniformity in Elementary Domains<br />

Linden, Henri; Martio, Olli, Editor; [2005]; ISSN 239-6303; 55 pp.; In English<br />

Report No.(s): Rept-146; Copyright; Avail.: Other Sources<br />

This work considers another definition of uniform domains, originally stated by F. Gehring <strong>and</strong> B. Osgood in [GeOs]. This<br />

alternative definition uses comparison between the quasihyperbolic <strong>and</strong> the distance ratio metrics <strong>and</strong> involves also a constant<br />

A greater than or equal to 1 which in general is not the same as the constant c in the definition by Martio <strong>and</strong> Sarvas. This<br />

alternative definition is better suited to the studies here <strong>and</strong> adhere to the uniformity concept of Definition 2.4 in this work.<br />

The class of uniform domains is very wide, for instance it includes images of the unit ball B(sup n) under a quasiconformal<br />

mapping of R(sup n) into itself. It is perhaps surprising that there are very few examples of domains for which the uniformity<br />

constant A is known, <strong>and</strong> in this work we study some of the simplest cases. In most cases this task involves identifying the<br />

geodesic segments of the given domain-in general a difficult problem. Often such precise analysis requires domain-specific<br />

methods; however, some techniques used might be of interest also in more general situations.<br />

Derived from text<br />

Domains; Geodesic Lines; Ratios<br />

20060001249 National Chung Hsing Univ., Taichung, Taiwan, Province of China<br />

Power System Load Frequency Control by Genetic Fuzzy Gain Scheduling Controller<br />

Juang, Chia-Feng; Lu, Chun-Feng; Journal of the Chinese Institute of Engineers; Vol. 28, No. 6; October 2005,<br />

pp. 1013-1018; In English; See also 20060001246; Copyright; Avail.: Other Sources<br />

A Genetic Algorithm (GA) based fuzzy gain scheduling approach for load frequency control is proposed in this paper. In<br />

this approach, a fuzzy system is used to adaptively decide the integral or PI controller gain according to the area control errors<br />

(ACE) <strong>and</strong> their changes. To reduce both the fuzzy system design effort <strong>and</strong> the number of fuzzy rules, the fuzzy system is<br />

designed automatically by genetic algorithms. To improve the design performance, a new genetic algorithm using elitist<br />

strategy combined with similarity measure on relatives between individuals is proposed. Based on similarity measure, mutated<br />

reproduction is adopted to increase the chance for reaching better solutions <strong>and</strong> to avoid premature phenomena. Simulations<br />

on a two-area interconnected power system with different kinds of perturbation are performed. The superiority of the proposed<br />

method over existing ones is verified from simulations <strong>and</strong> comparisons.<br />

Author<br />

Frequency Control; Genetic Algorithms<br />

20060001620 Massachusetts Inst. of Tech., Lexington, MA, USA<br />

Some Applications of Mathematical Morphology to Range Imagery<br />

Esselman, T. R.; Verly, J. G.; IEEE International Conference on Acoustics, Speech, <strong>and</strong> Signal Processing (ICASSP ‘87);<br />

Volume 1; 1987, pp. 7.10.01 - 7.10.4; In English; See also 20060001583; Copyright; Avail.: Other Sources<br />

Although little known, mathematical morphology (MM) offers great potential in the areas of image enhancement, feature<br />

181

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