• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.3
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• pp.525-532
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• 2021

In the ocean, it is difficult to separate the effects of one cause due to the multiple causes, but the self-organizing map can be analyzed by adding other factors to the cluster result. Therefore, in this study, the results of the clustering of sea level data were applied to sea surface temperature. Sea level data was clustered into a total of 6 nodes. The difference between sea surface temperature and sea level height has a one-month delay, which applied sea surface temperature data a month ago to the clustered results. As a result of comparing the mean of sea surface temperature of 140 to 150°E, where the sea surface temperature was variously distributed, in the case of nodes 1, 3, and 5, it was possible to find a meandering sea surface temperature distribution that is clearly distinguished from the sea level data. While nodes 2, 4 and 6, the sea surface temperature distribution was smooth. In this study, sea surface temperature data were applied to the clustered results of sea level data, but later it is necessary to apply wind or geostrophic velocity data to compare.

• Journal of the Korea Society for Simulation
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• v.18 no.3
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• pp.13-21
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• 2009

The sensor nodes that form a wireless sensor network must perform both routing and sensing roles, since each sensor node always has a regular energy drain. The majority of sensors being used in wireless sensor networks are either unmanned or operated in environments that make them difficult for humans to approach. Furthermore, since many wireless sensor networks contain large numbers of sensors, thus requiring the sensor nodes to be small in size and cheap in price, the amount of power that can be supplied to the nodes and their data processing capacity are both limited. In this paper, we proposes the WSN(Wireless Sensor Network) algorithm which is applied sensor node that has low power consumption and efficiency measurement. Moreover, the efficiency routing protocol is proposed in this paper. The proposed algorithm reduces power consumption of sensor node data communication. It has not researched in LEACH(Low-Energy Adaptive Clustering Hierarchy) routing protocol. As controlling the active/sleep mode based on the measured data by sensor node, the energy consumption is able to be managed. In the event, the data is transferred to the local cluster head already set. The other side, this algorithm send the data as dependent on the information such as initial and present energy, and the number of rounds that are transformed into cluster header and then transferred. In this situation, the assignment of each node to cluster head evenly is very important. We selected cluster head efficiently and uniformly distributed the energy to each cluster node through the proposed algorithm. Consequently, this caused the extension of the WSN life time.

• Korean Journal of Plant Resources
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• v.34 no.4
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• pp.297-310
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• 2021

Lonicera harae is a species of shrub in the Caprifoliaceae family, mostly distributed in East asia. So far, the related research on the genus of Lonicera is insufficient compared to the Lonicera japonica belonging to the same genus, which requires attention to domestic native plants. Therefore, this study aims to provide baseline data for cultivation and utilization through the growth environment and vegetation structure of the natural habitat. Lonicera harae, which plant found throughout the Korean Peninsula. The natural habitats of Lonicera harae is the forest, valley and lowland areas of the southern region. study examined 24 quadrats in 11 regions, including Gwangju, Wanju and Namhae. As a result, environmental condition of Lonicera harae was 8 to 483 m above sea level, normally distributed over 173 m, Slope was 5 to 25 degree with 8.5 degree on average. The list of plants were classified as a total of 229 taxa comprising 80 families, 166 genus, 198 species, 3 subspecies, 24 varieties, 4 forma. As a result of the clustering analysis, the three clusters were divided into three groups; Robinia pseudoacacia, Zelkova serrata, Larix kaempferi. Species diversity was 1.399 and Dominance and Evenness were found to be 0.978 and 0.022 respectively.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.439-448
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• 1999

To investigate the population dynamics and survival of Genus Vibrio, population densities of aerobic saprophytic bacteria and Vibrio groups were measured 4 times in the intertidal waters of the Yellow Sea near Kunsan from November, 1997 to June, 1998. The distribution of heterotrophic bacteria during the survey periods by plate count and direct count method ranged from 1.2$\pm$0.6$\times$10$^3$~2.0$\pm$1.5$\times$10$^4$CFU ml­$^1$and from 6.0$\pm$4.0$\times$10$^{5}$ ~1.9$\pm$1.5$\times$10$^{7}$ cells ml­$^1$, respectively. Vibrio groups were distributed in the range of 1$\times$10 and 6$\pm$2.2$\times$10$^2$CFU ml­$^1$. The proportion of Vibrio groups to total heterotrophic bacteria was between 0.1 and 6% during the survey periods. A total of 51 isolates was obtained from TCBS agar plates and identified to species level by Biolog Identification System$^{TM}$. As a result, dominant genera were V, mediterranei, V aitguillarum, tr metschnikovii, and V. parahaemolyticus, and isolates were clustered into 26 groups based on the relatedness of average linkage clustering method at 70% level. As for the susceptibility of 51 isolates to 7 kinds of antibacterial agents (gentamicin, ampicillin, chlorarnphenicol, streptomycin, kanamycin, tetracycline, carbenicillin), 96% of isolates showed high resistance to more than one antibiotics and 65% of isolates contained a plasmid, of which size was observed greater than 12 kb, The number of cells of 3 tested strains (V. anguillarum, V. vulnificus, and V. metschnikovii) in filtered aged seawater decreased by approximately 1 to 5 orders of magnitude during 30-d incubation. In most cases, the numbers of cells decreased rapidly until day 3, then decreased slowly by day 30. The number of cells incubated at 15$^{\circ}C$ showed higher survival than those at 4$^{\circ}C$ and $25^{\circ}C$. These results may be considered for the basic supporting data in the risk assessment of vibriosis in summer.r.

• Journal of Korea Game Society
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• v.4 no.4
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• pp.11-18
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• 2004

The on-line games in the past were played by only two persons exchanging data based on one-to-one connections, whereas recent ones (e.g. MMORPG: Massively Multi-player Online Role-playings Game) enable tens of thousands of people to be connected simultaneously. Specifically, Korea has established an excellent network infrastructure that can't be found anywhere in the world. Almost every household has a high-speed Internet access. What made this possible was, in part, high density of population that has accelerated the formation of good Internet infrastructure. However, this rapid increase in the use of on-line games may lead to surging traffics exceeding the limited Internet communication capacity so that the connection to the games is unstable or the server fails. expanding the servers though this measure is very costly could solve this problem. To deal with this problem, the present study proposes the load distribution technology that connects in the form of local clustering the game servers divided by their contents used in each on-line game reduces the loads of specific servers using the load balancer, and enhances performance of sewer for their efficient operation. In this paper, a cluster system is proposed where each Game server in the system has different contents service and loads are distributed efficiently using the game server resource information such as CPU utilization. Game sewers having different contents are mutually connected and managed with a network file system to maintain information consistency required to support resource information updates, deletions, and additions. Simulation studies show that our method performs better than other traditional methods. In terms of response time, our method shows shorter latency than RR (Round Robin) and LC (Least Connection) by about 12%, 10% respectively.

• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.211-230
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• 2016

Detailed mapping along the Keumwang fault reveals a complex history of multiple brittle reactivations following late Jurassic and early Cretaceous ductile shearing. The fault core consists of a 10~50 m thick fault gouge layer bounded by a 30~100 m thick damaged zone. The Pre-cambrian gneiss and Jurassic granite underwent at least six distinct stages of fault movements based on deformation environment, time and mechanism. Each stage characterized by fault kinematics and dynamics at different deformation environment. Stage 1 generated mylonite series along the Keumwang shear zone by sinistral ductile shearing during late Jurassic and early Cretaceous. Stage 2 was a mostly brittle event generating cataclasite series superimposed on the mylonite series of the Keumwang shear zone. The roundness of pophyroclastes and the amount of matrix increase from host rocks to ultracataclasite indicating stronger cataclastic flow toward the fault core. At stage 3, fault gouge layer superimposed on the cataclasite generated during stage 2 and the sedimentary basins (Umsung and Pungam) formed along the fault by sinistral strike-slip movement. Fragments of older cataclasite suspended in the fault gouge suggest extensive reworking of fault rocks at brittle deformation environments. At stage 4, systematic en-echelon folds, joints and faults were formed in the sedimentary basins by sinistral strike-slip reactivation of the Keumwang fault. Most of the shearing is accommodated by slip along foliations and on discrete shear surfaces, while shear deformation tends to be relatively uniformly distributed within the fault damage zone developed in the mudrocks in the sedimentary basins. Fine-grained andesitic rocks intruded during stage 4. Stage 5 dextral strike-slip activity produced shear planes and bands in the andesitic rocks. ESR(Electron Spin Resonance) dates of fault gouge show temporal clustering within active period and migrating along the strike of the Keumwang fault during the stage 6 at the Quaternary period.