• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.6
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• pp.2180-2200
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• 2015

This paper considers mobility control to improve packet delivery in delay-tolerant networks (DTNs) under group mobility. Based on the group structure in group mobility, we propose two mobility control techniques; group formation enforcement and group purposeful movement. Both techniques can be used to increase the contact opportunities between groups by extending the group's reachability. In addition, they can be easily integrated into some existing DTN routing schemes under group mobility to effectively expedite the packet delivery. This paper is divided into 2 parts. First, we study how our proposed mobility control schemes reduce the packet delivery delay in DTNs by integrating them into one simple routing scheme called group-epidemic routing (G-ER). For each scheme, we analytically derive the cumulative density function of the packet delivery delay to show how it can effectively reduce the packet delivery delay. Then, based on our second proposed technique, the group purposeful movement, we design a new DTN routing scheme, called purposeful movement assisted routing (PMAR), to further reduce the packet delay. Extensive simulations in NS2 have been conducted to show the significant improvement of PMAR over G-ER under different practical network conditions.

• PNF and Movement
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• v.15 no.3
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• pp.267-279
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• 2017

Purpose: The aim of the investigation was to identify the effects of purposeful activities combined with music on upper extremity function, motivation, and mood in acute stroke patients. Methods: For the study, 19 acute stroke inpatients were recruited at a general hospital in Korea. The patients were allocated between an experimental group (n=9) and a control group (n=10). The experimental group performed purposeful activities with their preferred music, and the control group carried out purposeful activities without music. The 2 groups received the treatments 30 min per day, 5 days per week, for 4 weeks. Measurements were taken before and after intervention, including a manual function test (MFT) for measuring upper extremity function, a volitional questionnaire (VQ) for assessing motivation, and the Beck depression inventory (BDI) and Beck anxiety inventory (BAI) for assessing mood. Results: In post-treatment measurement, both groups showed greater MFT, VQ, and BDI scores than in pre-treatment. Significantly greater VQ and BDI changes were represented in the experimental group as compared to the control group. Conclusion: Based on the findings of this study, purposeful activities combined with music have a positive effect on motivation and depression in acute stroke patients.