Wyniki wyszukiwania - BazTech

1

Segmental Mapping and Distance for Rooted Labeled Ordered Trees

Kan T., Higuchi S., Hirata K.

Fundamenta Informaticae

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2014

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Vol. 132, nr 4

461--483

EN

In this paper, as variations of a Tai mapping between rooted labeled ordered trees (trees, for short), we introduce a segmentalmapping to preserve the parent-children relationship as possible, and also top-down segmengal and bottom-up segmental mappings as the segmental mappings that contain the pair of the roots and the pair of the leaves, respectively. Then, we show that these mappings provide a new hierarchy for the variations of the Tai mapping in addition to a well-known one, in particular, the top-down segmental mapping coincides with a top-down mapping. Also we show that both segmental and bottom-up segmental distances as the minimumcosts of segmental and bottom-up segmental mappings are metrics. Next, we design algorithms to compute the segmental and the bottom-up segmental distances in quadratic time and space. Finally, we give experimental results for the segmental distance.

2

New Two-DOF Resonant Actuator Driven by Vector Control

Yoshimoto T., Asai Y, Hirata K., Ota T.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 7b

69-72

EN

This paper proposes a two-DOF resonant actuator that can be independently driven in two axes under vector control. Vector control is employed to control each drive axis independently by treating the field current element as the z-axis thrust element and the torque current element as the x-axis thrust element. The effectiveness of the actuator is verified by the experimental results of a prototype.

PL

Artykuł przedstawia aktuator rezonansowy z dwoma stopniami swobody, który może być niezależnie kierowany w dwóch osiach przez sterownik wektorowy. Sterowanie każdym kierunkiem może być niezależne poprzez traktowanie elementu prądowo-polowego jako osi z elementu siłowego, podczas gdy element prądowo-momentowy traktowany jest jako oś x elementu siłowego. Skuteczność aktuatora zweryfikowano w badaniach prototypu.

3

Asymmetric Acceleration Drive Using Linear Oscillatory Actuator under Open-Loop Control

Yoshimoto T., Hirata K., Asa Y., Ueyama K., Hashimoto E., Takagi T.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 7b

44-47

EN

This paper proposes an asymmetric acceleration drive method for linear oscillatory actuators under open-loop control. The effectiveness of this method is confirmed through the comparison of the 3-D FEM analysis results with the measurements of a prototype.

PL

W artykule przedstawiono asymetryczne urządzenie oscylacyjne dla liniowych aktuatorów ze sterowaniem otwarto-pętlowym. Efektywność metody analizy została potwierdzona poprzez porównanie analizy elementowo-skończeniowej z wynikami pomiarów3D.

4

Approximating Tree Edit Distance through String Edit Distance for Binary Tree Codes

Aratsu T., Hirata K., Kuboyama T.

Fundamenta Informaticae

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2010

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Vol. 101, nr 3

157-171

EN

This article proposes an approximation of the tree edit distance through the string edit distance for binary tree codes, instead of for Euler strings introduced by Akutsu (2006). Here, a binary tree code is a string obtained by traversing a binary tree representation with two kinds of dummy nodes of a tree in preorder. Then, we show that σ/2≤τ≤(h+1)σ+h, where τ is the tree edit distance between trees, and is the string edit distance between their binary tree codes and h is the minimum height of the trees.