• Journal of Communications and Networks
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• v.7 no.2
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• pp.104-114
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• 2005

This work presents a concept and the related analysis of the traffic performance for a wireless broadband system based on fixed relay stations acting as wireless bridges. The analysis focuses on the important performance indicators end-to-end throughput and delay, taking into account the effects of an automated repeat request protocol. An extension to a MAC frame based access protocol like IEEE 802.11e, 802.15.3, 802.16a, and HIPERLAN2 is outlined and taken as basis for the calculations. The system is intended for both dense populated areas as an overlay to cellular radio systems and to provide wide-area broad-band coverage. The two possible deployment scenarios for both dense urban and wide-area environments are introduced. Analytical and validating simulation results are shown, proving the suitability of the proposed concept for both of the mentioned scenarios. It is established that the fixed relaying concept is well suited to substantially contribute to provide high capacity cellular broad-band radio coverage in next generation (NG) cellular wireless broadband systems.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.6
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• pp.638-644
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• 2018

Relay systems have recently gained attentions because of its capability of cell coverage extension and the power gain as the one of key technologies for 5G. Relays can be exploited for small-cell base stations and the autonomous network, where communication devices communicate with each other cooperatively. Therefore, the relay technology is expected to enable the low power and large capacity communication. In order to maximize the benefits of using a limited number of relays, the efficient relay selection method is required. Especially, when two nodes exchange their data with each other via relay, the relay selection can maximize the average data rate by the spatial location of the relay. For this purpose, the average data rate is analyzed first according to the relay selection. In this paper, we analyzed the average data rate when two nodes exchange their data via dual-hop decode and forward relaying considering the interference by the concurrent transmission under Nakagami-m fading channel. The correctness of the analysis is verified by the Monte Carlo simulation. The results show that the concurrent transmission is superior to the non-concurrent transmission in the high required data rate region rather than in the low required data rate region.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.6B
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• pp.403-410
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• 2008

In this paper, we investigate the performance of MMR system in Non-transparent mode. The IEEE 802.16j MMR system has two node of operation, Single-frame (in band) and Multi-frame (out band) mode. In the analysis, we assume that channel interference between MR-BS and RS, or between RSs anywhere in the given area is ignored. The performance is presented in terms of the delay and the frame efficiency by varying number of RS and BS coverage to RS coverage ratio and the maximum coverage area of a BS by varying traffic density. Analytical results show that the Single-frame is more efficient than Multi-frame in frame efficiency and coverage extension.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.3
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• pp.165-173
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• 2021

Purpose : Myofascial decompression is frequently mentioned as a method applied to cupping. The purpose of this study is to evaluate and compare active range of motion (AROM), muscle strength, and functional movement by applying myofascial decompression to the hamstrings. Methods : This study evaluated AROM, muscle strength, and functional movement by applying active movement myofascial decompression and static myofascial decompression to the dominant leg, respectively, in a crossover design conducted with normal adults (n=21) in their average 20s enrolled at G University in G city, Gyeongsangbuk-do. Active movement myofascial decompression was implemented for five minutes at a rate of 100 bpm to make the beats in flexion and extension respectively. Static myofascial decompression was only performed for five minutes while at rest. All of these interventions were performed at a cupping depth of two mm. After a one-week washout period, static was applied again to compare the same dependent variables. Results : Regarding AROM and muscle strength, both groups showed significant differences in the before and after results (p<.05). However, in the Functional Reach Aspect and Single Leg Hop test, the active movement myofascial decompression group showed better results. There was no statistical difference between the Active movement myofascial decompression group and Static myofascial decompression group in any dependent variable (p<.05). Conclusion : As a result of this experiment, both active movement myofascial decompression and static myofascial decompression had a positive effect on dependent variable. Therefore this study is meaningful in that it is easier and simpler to see the effect on flexibility, muscle strength, and functional movement just by implementing movement myofascial decompression.