Wyniki wyszukiwania - BazTech

1

Development of a shape memory alloy wire actuator to operate a morphing wing

Rim M., Kim E.-H., Kang W.-R., Lee I.

Journal of Theoretical and Applied Mechanics

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2014

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Vol. 52 nr 2

519--531

EN

DSC tests were performed on several types of SMAs to verify the phase-transformation temperatures, and then experiments to examine their characteristics were carried out. An electric-current was supplied to the SMA wire to measure the appropriate operational cur- rent range. The force generated by the SMA wire increased according to the supplied current, but it diminished when the over-current was supplied because thermo-mechanical properties of the wire started to degrade. The appropriate stress range for effective actuation charac- teristics was also investigated. The SMA wire actuator was designed to operate a morphing wing. Experiments for the wing were conducted to verify its characteristics and it was smo- othly deformed.

2

Low-velocity impact characteristics of composite plates with shape memory alloy wires

Rim M.-S., Kim E.-H., Lee I., Choi I.-H., Ahn S.-M., Koo K.-N., Bae J.-S., Roh J.-H.

Journal of Theoretical and Applied Mechanics

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2011

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Vol. 49 nr 3

841-857

EN

To investigate impact characteristics of shape memory alloy hybrid com- posites (SMAHC), several experiments were performed. Tensile tests of shape memory alloy (SMA) wires were carried out to investigate thermomechanical properties, and low-velocity impact tests of SMAHC plates and conventional composite plates without SMAs at the critical energy level. low-velocity impact tests of several types of composite plates, including composite plates with embedded SMAs/Fe/Al wires and conventional composite plates, were also done. Results of these experiments show that embedding SMAs in a composite plate can improve the impact resistance. Lastly, low-velocity impact tests of SMAHC plates with SMA wires embedded at different positions through the thickness were performed in an effort to improve the impact resistance. Embedding SMA wires at a lower position in the composite plates was the most effective for improving the impact resistance.

PL

Do analizy charakterystyk uderzeniowych hybrydowych kompozytów SMAHC zwierających włókna SMA ze stopów wykazujących efekt pamięci kształtu przeprowadzono szereg badań eksperymentalnych. Przeprowadzono próby na rozciąganie włókien SMA w celu zbadania ich właściwości termomechanicznych oraz niskoprędkościowe testy uderzeniowe płyt SMAHC oraz konwencjonalnych płyt laminowanych przy energii krytycznej. Wykonano także testy dla płyt kompozytowych zawierających włókna SMA/Fe/Al. Rezultaty doświadczeń pokazały, że wbudowanie w strukturę laminatu włókien SMA może zwiększyć odporność kompozytu na obciążenie uderzeniowe. Opisano również badania eksperymentalne płyt SMAHC z włóknami SMA wbudowanymi na różnej głębokości. Wykazano, że najlepsze parametry posiadają kompozyty z włóknami umieszczonymi możliwie daleko od uderzanej powierzchni.

3

A Simple and Scalable Algorithm for the IP Address Lookup Problem

Lee I., Park K., Choi Y., Chung S.K.

Fundamenta Informaticae

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2003

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Vol. 56, nr 1,2

181-190

EN

The IP address lookup problem is to find the longest matching IP prefix from a routing table for a given IP address and it has been a central bottleneck in speeding up the Internet. In this paper we propose a new algorithm for this problem based on the segment tree data structure. Given n IP prefixes, our algorithm does the IP address lookup in O(logn) time. It also handles the insertion and deletion of IP prefixes efficiently without rebuilding the whole data structure.