• Current Photovoltaic Research
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• v.6 no.1
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• pp.1-11
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• 2018

Current major photovoltaic (PV) market share (> 60%) is being occupied by the multicrystalline (mc)-silicon solar cells despite of low efficiency compared to single crystalline silicon solar cells. The diamond wire sawing technology reduces the production cost of crystalline silicon solar cells, it increases the optical loss for the existing mc-silicon solar cells and hence its efficiency is low in the current mass production line. To overcome the optical loss in the mc-crystalline silicon, caused by the diamond wire sawing, next generation texturing process is being investigated by various research groups for the PV industry. In this review, the limitation of surface structure and optical loss due to the reflectivity of conventional mc-silicon solar cells are explained by the typical texturing mechanism. Various texturing technologies that could minimize the optical loss of mc-silicon solar cells are explained. Finally, next generation texturing technology to survive in the fierce cost competition of photovoltaic market is discussed.

• Nuclear Engineering and Technology
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• v.30 no.5
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• pp.435-443
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• 1998

Leak-before-break(LBB) approach has been shown to be both cost effective and risk reductive when applied to high energy Piping in nuclear Power Plants. For the Korean Next Generation Reactor (KNGR) development, LBB application is considered for the Main Steam Line(MSL) piping inside containment. Unlike the primary system leakages, the MSL leak detection systems must be based on principles other than radioactivity measurements. Among humidity, heat and acoustic noise currently being considered as indicators of leakage, we explored humidity as an effective one and developed ceramic-based humidity sensor which can be qualified for LBB applications. The ceramic material, sintered and annealed MgCr$_2$O$_4$-TiO$_2$, is shown to increase its electrical conductivity drastically upon water vapor adsorption over the entire temperature range of interest. With this ceramic sensor specimen, we suggested installation-inside-the-piping method by which we can detect leakage more rapidly and sensitively. In this paper, we describe the progress in the development and characterization of ceramic humidity sensor for the LBB application to the MSL of KNGR.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.2
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• pp.90-99
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• 2007

We demonstrate an 80km-reach 64-channel DWDM-PON based on wavelength-locked F-P LDs by changing the position of the C-band BLS for upstream channels from the CO to the RN. It mitigates the necessity of the high power C-band BLS and its handling problems. It also reduces back scattering induced penalty. We obtained less than $10^{-6}$ PLRs in all 128channels through 80km SMF. We also demonstrate a 240km-reach DWDM-PON based on wavelength-locked F-P LDs by adding a bidirectional erbium-doped fiber amplifier(EDFA). We show packet-loss-free transmission in all 128channels at 125 Mb/s per channel over 240km SMF We report the detuning effect of arrayed waveguide gratings(AWGs) and crosstalk effect in the implemented system. We Propose an architecture of a next generation defense wire communication system with the demonstrated long-reach DWDM-PON.

• Genomics & Informatics
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• v.12 no.4
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• pp.289-292
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• 2014

Next-generation sequencing (NGS) is widely used to identify the causative mutations underlying diverse human diseases, including cancers, which can be useful for discovering the diagnostic and therapeutic targets. Currently, a number of single-nucleotide variant (SNV)-calling algorithms are available; however, there is no tool for visualizing the recurrent and phenotype-specific mutations for general researchers. In this study, in order to support defining the recurrent mutations or phenotype-specific mutations from NGS data of a group of cancers with diverse phenotypes, we aimed to develop a user-friendly tool, named mutation arranger for defining phenotype-related SNV (MAP). MAP is a user-friendly program with multiple functions that supports the determination of recurrent or phenotype-specific mutations and provides graphic illustration images to the users. Its operation environment, the Microsoft Windows environment, enables more researchers who cannot operate Linux to define clinically meaningful mutations with NGS data from cancer cohorts.

• Journal of the Korean Society for information Management
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• v.27 no.4
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• pp.89-107
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• 2010

Open access journal has been one of the major academic information sources for researcherscharacterizing itself as free resource. Recently, as competition among academic information service provides becomes intense, open access journal also needs to enhance its service and expand information service function. This study aims to propose service features for next generation service of open access journals by analyzing service features of leading journal database services. As a result, four service features are suggested such as journal article components and multimedia features, expanded searching features, social service features and mobile information service.

• World Technopolis Review
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• v.7 no.2
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• pp.125-134
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• 2018

The purpose of this article is to introduce and describe the case of Fukuoka Next-generation Social System Creation Hub based on the conceptual framework of regional innovation platform strategy. In short, it is a "government-issued" regional innovation platform strategy to improve innovativeness with limited creative capital through "borrowing" not money but network, wisdom, know-how, and ideas from each other between some stakeholder groups in a region. The Fukuoka Industry, Science & Technology Foundation, which is the coordinating institution of the whole program, plays the role of a platformer to unify various projects into the program crossing borders between stakeholder groups for building regional innovation platforms that lends intensive support to feedback loops between the program facilitator and its partners in the program. Thanks to being a government-issued one, it could be tied together with some wide ranging issues of policy on social innovations, such as the "low carbon society" or the "health and longevity society." But at the same time, it is a concern that many regional research institutions that have innovative potential and diverse ideas become governed by the platform without their noticing it and dealt with in the same way based on "selected" and "designated" strategic goals. Therefore, it seems that a regional innovation platform strategy is a kind of "double-edged sword" in public policy in the era of "panopticism of bureaucratic society" in Japan.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.440-448
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• 2021

Helicobacter pylori (H. pylori) establishes long-term infections associated with severe gastric diseases such as peptic ulceration and gastric cancer. Exposure to an antibacterial agent can help regulate the expression levels of its pathogenic genes. In this study, we analyzed the transcriptional changes in H. pylori genes induced by β-caryophyllene. We used next-generation sequencing (NGS) to analyze RNA expression changes, and reverse transcription-polymerase chain reaction (RT-PCR) was performed as required to verify the results. The NGS results showed that 30 out of 1,632 genes were expressed differentially by β-caryophyllene treatment. Eleven genes associated with DNA replication, virulence factors, and T4SS components were significantly downregulated. RT-PCR confirmed that treatment reduced the expression levels of 11 genes. RT-PCR showed the reduced expression of 11 genes (dnaE, dnaN, holB, gyrA, cagA, vacA, secA, flgE, virB2, virB4, and virB8) following β-caryophyllene treatment. These results suggest that β-caryophyllene can modulate various H. pylori pathogenic determinants and be a potential therapeutic agent for H. pylori infection.

• Microbiology and Biotechnology Letters
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• v.48 no.4
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• pp.574-581
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• 2020

Next generation sequencing is commonly used to characterize the microbiome structure. MiSeq is commonly used to analyze the microbiome due to its relatively long read length. However, recently, Illumina introduced the 250x2 chip for HiSeq 2500. The purpose of this study was to compare the performance of MiSeq and HiSeq in the context of oral microbiome samples. The MiSeq Reagent Kit V3 and the HiSeq Rapid SBS Kit V2 were used for MiSeq and HiSeq 2500 analyses, respectively. Total read count, read quality score, relative bacterial abundance, community diversity, and relative abundance correlation were analyzed. HiSeq produced significantly more read sequences and assigned taxa compared to MiSeq. Conversely, community diversity was similar in the context of MiSeq and HiSeq. However, depending on the relative abundance, the correlation between the two platforms differed. The correlation between HiSeq and MiSeq sequencing data for highly abundant taxa (> 2%), low abundant taxa (2-0.2%), and rare taxa (0.2% >) was 0.994, 0.860, and 0.416, respectively. Therefore, HiSeq 2500 may also be compatible for microbiome studies. Importantly, the HiSeq platform may allow a high-resolution massive parallel sequencing for the detection of rare taxa.

• Electronics and Telecommunications Trends
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• v.37 no.5
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• pp.11-21
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• 2022

GaN (Gallium-Nitride) is a promising candidate material in various radio frequency applications due to its inherent properties including wide bandgap, high carrier concentration, and high electron mobility/saturation velocity. Notably, AlGaN/GaN heterostructure field effect transistor exhibits high operating voltage and high power-density/power at high frequency. In next-generation radar systems, GaN power transistors and monolithic microwave integrated circuits (MMICs) are significant components of transmitting and receiving modules. In this paper, we introduce technological trends for C-/X-/Ku-band GaN MMICs including power amplifiers, low noise amplifiers and switch MMICs, focusing on the status of GaN MMIC fabrication technology and GaN foundry service. Additionally, we review the research for the localization of C-/X-/Ku-band GaN MMICs using in-house GaN transistor and MMIC fabrication technology. We also discuss the results of C-/X-/Ku-band GaN MMICs developed at Defense Materials and Components Convergence Research Department in ETRI.

• Mycobiology
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• v.49 no.6
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• pp.559-581
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• 2021

The coastal marine ecosystems of Vietnam are one of the global biodiversity hotspots, but the biodiversity of marine fungi is not well known. To fill this major gap of knowledge, we assessed the genetic diversity (ITS sequence) of 75 fungal strains isolated from 11 surface coastal marine and deeper waters in Nha Trang Bay and Van Phong Bay using a culture-dependent approach and 5 OTUs (Operational Taxonomic Units) of fungi in three representative sampling sites using next-generation sequencing. The results from both approaches shared similar fungal taxonomy to the most abundant phylum (Ascomycota), genera (Candida and Aspergillus) and species (Candida blankii) but were different at less common taxa. Culturable fungal strains in this study belong to 3 phyla, 5 subdivisions, 7 classes, 12 orders, 17 families, 22 genera and at least 40 species, of which 29 species have been identified and several species are likely novel. Among identified species, 12 and 28 are new records in global and Vietnamese marine areas, respectively. The analysis of enzyme activity and the checklist of trophic mode and guild assignment provided valuable additional biological information and suggested the ecological function of planktonic fungi in the marine food web. This is the largest dataset of marine fungal biodiversity on morphology, phylogeny and enzyme activity in the tropical coastal ecosystems of Vietnam and Southeast Asia. Biogeographic aspects, ecological factors and human impact may structure mycoplankton communities in such aquatic habitats.