• The KIPS Transactions:PartC
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• v.14C no.7
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• pp.597-602
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• 2007

In conventional cooperative communication data rate is 1/2 than non cooperative protocols. In this paper, we propose a full data rate DF (Decode and Forward) cooperative transmission scheme. Proposed scheme is based on time division multiplexing (TDM) channel access. When DF protocol has full data rate, it can not obtain diversity gain under the pairwise error probability (PEP) view point. If it increases time slot to obtain diversity gain, then data rate is reduced. The proposed algorithm uses orthogonal frequency and constellation rotation to obtain both full data rate and diversity order 2. Moreover, performance is analyzed according to distance and optimized components that affect the system performance by using computer simulation. The simulation results revealed that the cooperation can save the network power up to 7dB over direct transmission and 5dB over multi-hop transmission at BER of $10^{-2}$. Besides, it can improve date rate of system compared with the conventional DF protocol.

• Journal of Korea Multimedia Society
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• v.16 no.1
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• pp.56-66
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• 2013

In MANET, the frequent movement of nodes causes the dynamic network topology changes. Therefore, it is required that the routing protocol should be very stable to effectively respond the changes of the network changes. Moreover, the existing cluster-based routing protocol, that is the hybrid approach, has routing delay due to the re-electing of the cluster header. In addition, the routing table of CBRP has all only one hop distant neighbor nodes. PCBRP, proposed in this paper, ties two clusters in one paired cluster to make longer radius. Then the headers of the paired cluster manage and operate corresponding member nodes. In the current CBRP, when the cluster header leaves out the cluster, the delay, due to the re-electing a header, should be occurred. However, in PCBRP, another cluster header of the paired cluster plays the role instead of the left cluster header. This method reduces the routing delay. Concurrently, PCBRP reduces the delay when they route nodes in the paired cluster internally.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1B
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• pp.16-23
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• 2009

This paper investigates how many optimal routes can be established in terms of a given wireless mesh routing metric. Although many of routing metrics have been devised to precisely derive the wireless link quality in mesh, most (if not all) metrics have not been evaluated their optimality along with routing protocols. We consider stateof-the-art routing metrics and a widely accepted routing protocol in order to observe the optimality of established routes varying the number of source nodes. Also, we propose a unidirectional routing to deal with possible link asymmetry feature in wireless links. Through comparative simulation evaluations, we show that the portion of optimally established routes becomes less as the network traffic load increases, regardless of employed metrics, network topologies, and routing protocols.

• The KIPS Transactions:PartC
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• v.9C no.6
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• pp.919-926
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• 2002

In this paper, new multicast scheduling algorithms are proposed for the WDM single-hop broadcast-and-select networks. The existing multicast scheduling algorithms are focused on the partitioning a multicast group into several subgroups to reduce the delay time of each receiver. These partitioning algorithms are grouping method of the receivers already tuned to the transmitter's wavelength. However, these algorithms ignore the state of receivers, which leads to increase the number of subgroups and the delay time. Therefore, 1 propose two new multicast scheduling algorithms called H_EAR and PGM that partition a multicast group to subgroups using the tunable transmitter, state information of receivers, and pseudo group concept. The performance of proposed algorithms are evaluated through the computer simulation. They show the better performance comparing with the existing multicast scheduling algorithm.

• The Korean Journal of Mycology
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• v.6 no.1
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• pp.29-41
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• 1978

This study aims to brew apple wine containing lower concentration of alcohol by fermentation and to retain $CO_2$ gas in apple wine, and investigation for the possibility of storage at room temperature was performed. A Saccharomyces sp. was proved to be acceptable for production of base wine as its higher fermentation rate at $20{\sim}25^{\circ}C$. However, B-2 was most reasonable for post-fermentation of apple wine as this strain strongly ferments sugars at low temperature $(4^{\circ}C)$. The yield of apple juice increased by maceration of apple pulps. The yield was about 5 % more than that of the unmacerated juice, whereas acid content was decreased by 10% compared with control. When stored apple wine containing 9% alcobol was introduced $1{\sim}3%$ sucrose at $7{\sim}8^{\circ}C$ for 100 days or more, the $CO_2$ pressure of apple wine in bottle shows $3kg/cm^2$ by bottle-pressure meter. It showed good storage of the wine at room temperature. $CO_2$ gas pressure in apple wine containing 6% alcohol, $5{\sim}10%$ hop extract, and 2% sugar was $2kg/cm^2$, he result also showed possibility of storage. Whereas 6% concentration of alcoholic apple wine without hop extract caused unusual fermentation during storage at the same condition. The desirable conditions for high quality apple wine should have $CO_2$ pressure of $2kg/cm^2$ or more and should be added $1{\sim}2% sugar to base wine. From these results, it can be concluded that the brewing of lower alcoholic apple wine is possible.

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1723-1729
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• 2018

The aim of this work is to investigate the protective efficacy of emodin, an active, naturally-occurring anthraquinone derivative of several traditional Chinese herbs, against Brucella abortus infection in macrophages. Brucella were incubated with different concentrations of emodin and showed that bacterial survival rates were markedly reduced in a dose-dependent manner at increasing incubation time points. Through bacterial infection assay, the highest non-cytotoxic concentration of emodin demonstrated attenuated invasion of Brucella into macrophages, however it did not inhibit the growth of these pathogens within the host cells. On the other hand, emodin effectively decreased the number of bacteria that adhered to host cells, which indicated its potential as an anti-adhesin agent. Furthermore, using immunoblotting and FACS assay for detecting MAPK signaling proteins and F-actin polymerization, respectively, the results showed that the emodin-incubated cells displayed modest reduction in the phosphorylation levels of ERK1/2 and inhibition of F-actin polymerization as compared to control cells. These findings indicate the potential use of emodin as a naturally-occurring alternative method for the prevention of animal brucellosis although this requires confirmation of safe clinical doses.

• Korean Journal of Acupuncture
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• v.26 no.3
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• pp.77-85
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• 2009

Objectives : The lower sea points of the six bowels is one of the most useful acupuncture prescription in the treatment for diseases related with six organs. There have been many studies on the effects of each acupoint, but it is difficult to find a systemic review about the whole of it. The purpose of this study is to review the lower sea points of the six bowels and investigate the background of the induction of that. Materials and Methods : 1. The authors performed systemic review about the lower sea points of the six bowels using related-literatures such as Neijing and Nanjing. 2. We investigated the background of the induction and the necessity through the meaning of the character Hop (合). We thought the clinical usefulness of that. Results and Conclusions : The lower sea points of the six bowels had been made for the supplement of the sea point of the five transport points and it might be possible to substitute the sea point of the five transport points with the lower sea points of the six bowels owing to the clinical usefulness of the lower sea points of the six bowels.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.30 no.1
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• pp.61-73
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• 2024

Background: The purpose of this study is to investigate the effect of ankle strengthening and proprioceptor exercise, including gluteus-medius strengthening exercise, on ankle strength, dynamic and static balance, ankle function, and quality of life in 24 adults without ankle instability. Methods: After randomly classifying 12 people per group into the experimental group and the control group, Home-exercise rehabilitation program was conducted for a total of 2 weeks. The control group performed ankle strengthening and proprioceptor exercise 5 times a week for 15 minutes, and the experimental group was performed by adding 15 minutes of gluteus-medius strengthning exercise to the exercise performed by the control group. The SPSS 27.0 program was used for statistical analysis. Results: Both groups showed statistically significant differences in the plantar flexion muscle strength, Y-Balance test, side hop test, quality of life. But, only experimental group showed statistically significant differences dorsi-flexion muscle strength and hip abduction muscle strength. There was no statistical difference in comparison of difference values between groups. Conclusion: These exercises can provide useful home rehabilitation programs for sports populations seeking to prevent injury in sports.

• The KIPS Transactions:PartA
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• v.12A no.6 s.96
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• pp.557-562
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• 2005

Throughput and latency of interconnection network are important factors of the performance of multiprocessor systems. The dual-link CC-NUMA architecture using point-to-point unidirectional link is one of the popular structures in high-end commercial systems. In terms of optimal path between nodes, several paths exist with the optimal hop count by its native multi-path structure. Furthermore, transaction latency between nodes is affected by congestion of links on the transaction path. Hence the transaction latency may get worse if the transactions make a hot spot on some links. In this paper, I propose a dynamic transaction routing algorithm that maintains the balanced link utilization with the optimal path length, and I compare the performance with the fixed path method on the dual-link CC-NUMA systems. By the proposed method, the link competition is alleviated by the real-time path selection, and consequently, dynamic transaction algorithm shows a better performance. The program-driven simulation results show $1{\~}10\%$ improved fluctuation of link utilization, $1{\~}3\%$ enhanced acquirement of link, and $1{\~}6\%$ improved system performance.

• Journal of Digital Convergence
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• v.12 no.9
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• pp.465-474
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• 2014

This research aimed to enhance the effects of training through the use of infrared cameras located at anterior and posterior positions. The results were as follows. In the case of the smash, the impact time needed to be adjusted to raise their impact point. The smash of S1, on the other hand, was a step smash, which showed the fastest racquet head speed and the greatest transmission of power upon impact. As the max racquet speed upon impact and during speed was similar, S1 showed the best impact time. All athletes except S6 were shown to use their right foot as their 1 step that was located in front upon landing, using a hop step as their first step. For the best swing upon stroke, it is important to make the best conditions possible for the use of elbow joints and wrist joints. The rotating radius of the racquet should be big and the shuttlecock should be fast. Balance is important in footwork, or the coordinated movement of the feet. Without a correct step it is difficult to execute an efficient stroke. In an actual game, steps need to be executed in 2 to 4 steps, and programs focusing on steps according to situation, agility and reaction need to be executed.