• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.594-597
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• 2012

Optimal link configuration in optical link with concentrated residual dispersion per span (RDPS) in only one fiber span and 0 ps/nm of RDPS in other fiber spans of each half transmission section with respect to optical phase conjugator (OPC) placed at middle of total transmission length is induced in this paper.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.7
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• pp.421-428
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• 2003

After the cable is installed, many geometric factors, such as bowing types of the cable and the length difference of the cable between each minor section will cause the impedance unbalance between cables. The impedance unbalance will increase or decrease the sheath circulating currents, which are critical to human safety and sustaining the capabilities of electric power. Accordingly, in this paper, a new method is also proposed to reduce the sheath circulating currents and an reduction equipment according to the theory of the new method is developed. The reduction equipment is tested when the cable is on service. The test results show that it can reduce the sheath circulating currents by up to 97.8［%］. This confirms the validation of the new method and the reduction equipment, and assures the safe operation of the transmission cables. In order to illustrate the safe operation of the cable with new current reduction equipment at transient state due to lightning and single line-to-ground fault, extensive simulations have been made. Then the protection scheme of sheath circulating currents reduction equipment is proposed by adopting the new device of RDP(Reduction Device Protector).

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.9
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• pp.4063-4086
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• 2016

Cloud computing is a robust technology, which facilitate to resolve many parallel distributed computing issues in the modern Big Data environment. Hadoop is an ecosystem, which process large data-sets in distributed computing environment. The HDFS is a filesystem of Hadoop, which process data blocks to the cluster nodes. The data block placement has become a bottleneck to overall performance in a Hadoop cluster. The current placement policy assumes that, all Datanodes have equal computing capacity to process data blocks. This computing capacity includes availability of same storage media and same processing performances of a node. As a result, Hadoop cluster performance gets effected with unbalanced workloads, inefficient storage-tier, network traffic congestion and HDFS integrity issues. This paper proposes a storage-tier-aware Robust Data Placement (RDP) scheme, which systematically resolves unbalanced workloads, reduces network congestion to an optimal state, utilizes storage-tier in a useful manner and minimizes the HDFS integrity issues. The experimental results show that the proposed approach reduced unbalanced workload issue to 72%. Moreover, the presented approach resolve storage-tier compatibility problem to 81% by predicting storage for block jobs and improved overall data block placement by 78% through pre-calculated computing capacity allocations and execution of map files over respective Namenode and Datanodes.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.3
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• pp.157-165
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• 2019

This study was conducted to analyze the diversity census of fecal microbiome in horses using meta-analysis of equine 16S rRNA gene sequences that are available in the Ribosomal Database Project (RDP; Release 11, Update 5). The search terms used were "horse feces (or faeces)" and "equine feces (or faeces)". A total of 842 sequences of equine feces origin were retrieved from the RDP database, where 744 sequences were assigned to 10 phyla placed within Domain Bacteria. Firmicutes (n = 391) and Bacteroidetes (n = 203) were the first and the second dominant phyla, respectively, followed by Verrucomicrobia (n = 58), Proteobacteria (n = 30) and Fibrobacteres (n = 24). Clostridia (n = 319) was the first dominant class placed within Bacteroidetes while Bacteroidia (n = 174) was the second dominant class placed within Bacteroidetes. The remaining 98 sequences were assigned to phylum Euryarchaeota placed within Domain Archaea, where 74 sequences were assigned to class Methanomicrobia. The current results will improve understanding of the diversity of fecal microbiome in horses and may be used to further analyze equine fecal microbiome in future studies.

• Journal of Advanced Navigation Technology
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• v.19 no.6
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• pp.595-600
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• 2015

The implementation possibility of the flexible optical network configuration using the non-midway optical phase conjugator (OPC) in the dispersion-managed (DM) optical link for wavelength division multiplexed (WDM) transmission is demonstrated in this paper. It is confirmed that the implementation possibility of flexible link configuration is more increased, as number of fiber spans is more bigger and the residual dispersion per span (RDPS) is more large. It is also confirmed that the non-midway OPC link, in which RDPS of the latter half transmission section (after OPC) is decided by the averaged RDPS of the former half transmission section (before OPC), has more advantage for the flexible network configuration.

• Journal of Advanced Navigation Technology
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• v.17 no.1
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• pp.16-23
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• 2013

The effects of dispersion coefficient of dispersion compensating fiber (DCF) and residual dispersion per span (RDPS) on in the dispersion managed optical links for compensating the distorted 960 Gbps wavelength division multiplexd (WDM) signals due to group velocity dispersion (GVD) and optical nonlinear effects of single mode fiber (SMF) are investigated. It is confirmed that optimal net residual dispersion (NRD), which greatly affects compensating for optical signals, should be induced under the large launch power condition, irrelevant on the considered dispersion coefficient of DCF and RDPS. It is also confirmed that system performances are greatly improved by selecting the very small RDPS and very large dispersion coefficient of DCF.

• Journal of Advanced Navigation Technology
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• v.13 no.5
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• pp.656-661
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• 2009

High-quality transmission of $24{\times}40$ Gbps WDM signals obtained through controling residual dispersion per span (RDPS) in optical transmission links with zero net residual dispersion (NRD) of inline dispersion management (DM) of optical transmission links is researched. It is confirmed that RDPS values, which is improving system performance, depends on launch power of WDM channels, but optimal RDPS, which can simultaneously improve WDM signals with relative wide launch power ranges, becomes to be 210~230 ps/nm. Also, it is shown that effective launch power range that making eye opening penalty (EOP) of worst channel to below 1 dB is more increased as RDPS is more increased.

• Journal of Advanced Navigation Technology
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• v.19 no.4
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• pp.323-329
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• 2015

The compensation characteristics of the distorted WDM channels compensated for by dispersion management (DM) and optical phase conjugation in the long-haul ($50\;fiber\;spans{\times}80km$) transmission link with the randomly distributed single mode fiber (SMF) length and residual dispersion per spans (RDPS) for implementing of the flexible link configuration are investigated. It is confirmed that the compensation effect in the link with the randomly distributed SMF length and RDPS is similar with that in the link with the uniform distribution, when the launch power of WDM channels are restricted within 0 dBm. This result means that the proposed link configuration is useful for designing and deploying the long-haul WDM transmission link.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.975-977
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• 2013

The optimal distribution pattern is induced in the optical link with an artificial distributions of single mode fiber (SMF) lengths and residual dispersion per span (RDPS). It is confirmed that the descending distribution of SMF length and ascending distribution of RDPS are most suitable to compensate for the distorted WDM signals, as the fiber span number is more increased. in the optical link with 10 ps/nm or -10 ps/nm the optimal net residual dispersion (NRD).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.964-966
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• 2015

The effect of the deviations of single mode fiber lengths and residual dispersion per span (RDPS) on the compensation for the distorted WDM signals in the dispersion-managed optical links with the specially artificial distributions of the lengths of SMFs and RDPSs. The considered artificial distribution is following; the lengths of SMF and RDPSs between the adjacent fiber span are more descended in the half transmission section from transmitter to optical phase conjugator (OPC), and those are more ascended in the rest half transmission section from OPC to the receiver, as number of fiber spans are more increased.