• Korean journal of applied entomology
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• v.44 no.2
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• pp.145-150
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• 2005

Three Korean isolates of entomopathogenic nematodes, Steinernema carpocapsae KCTC 0981BP (ScK), S. glaseri Dongrae (SgD), and Heterorhabditis sp. KCTC 0991BP (HsK), were evaluated for the control of a turfgrass pest, Popillia quadriguttata. Three days after treatment, all nematodes showed high pathogenicity to adult P. quadriguttata with $97.5\%$ mortality by ScK, $90.8\%$ by HsK, and $80\%$ by SgD at the concentration of 900 infective juveniles per adult. Nematode attachment and infection rate to adult P. quadriguttata were various depending on nematode species and inoculation density. The rate of nematode attachment was $90.8\%$ in HsK, $90.6\%$ in SgD, and $35\%$ in ScK, resfectively at the concentration of 900 infective juveniles per adult. The infection rate that represents the rate of detected nematode from inside insect of body was $97.5\%$ in ScK, $ 80\%$ in both HsK and SgD at the 900 concentration of infected juveniles. The infection rate, however, was decreased to $27.5\%$ in ScK, $72.5\%$ in SgD, but no nematodes was detected in HsK at the concentration of 90 infective juveniles.

• Journal of Electrochemical Science and Technology
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• v.10 no.3
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• pp.257-270
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• 2019

The inhibition performance of sodium gluconate (SG), cetyltrimethylammonium bromide (CTAB) and their mixture (SG/CTAB) on the corrosion behavior of ${\alpha}$-brass in 0.5 M $H_2SO_4$ solution has been investigated by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), Scanning Electron Microscope with Energy-Dispersive Spectrometer (SEM-EDS), Inductively Coupled Plasma Spectrometry (ICPS) and molecular dynamics (MD) simulation techniques. The results reveal that SG with 5ppm CTAB, noted SG/CTAB, acts as a good corrosion inhibitor and its inhibition efficiency reached 89% after 24 h immersion in sulfuric acid solution, but slightly decreased at higher temperatures. The polarization curves displayed that SG/CTAB acts as a cathodic-kind inhibitor. Electrochemical impedance spectroscopy (EIS) studies revealed that the addition of 5ppm CTAB to different concentrations of SG considerably increases the corrosion resistance of ${\alpha}$-brass. The SEM-EDS and ICPS analyses support the experimental results. Further, molecular dynamics (MD) simulations were used to understand the adsorption profiles of SG/CTAB on Cu(111) and Zn(111) surfaces.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.147-151
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• 2007

Laboratory tests were conducted to determine the susceptibility of the alfalfa weevil, Hypera postica to Korean entomopathogenic nematodes, Steinernema carpocapsae GSN1 strain (ScG), S. glaseri Dongrae strain (SgD), Heterorhabditis bacteriophora Hamyang strain (HbH), and Heterorhabditis sp. Gyeongsan strain (HeG) at the petri dish assay. The larval mortality of H. postica was significantly different depending on nematode species and treatment concentration. SgD and HeG strain were more effective against H. postica larva than ScG and HbH strain. When SgD and HeG strain were treated with the rate of >20 infective juveniles (ijs) per alfalfa weevil larva, mortality was ca. 77.5-100% at the late instars of H. postica in 3 days. The number of established nematode was significantly different depending on nematode species, whereas number of progeny was not significantly different. The mean number of established us of SgD strain in a host was the highest at 80 ijs by 30.2. The highest progeny number of HeG strain was 2,671.5 with 80 ijs. All nematode strains were not parasitic entirely to H. postica adults. These results show that alfalfa weevil late larva is highly susceptible to Korean entomopathogenic nematodes in the laboratory.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.12
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• pp.1-8
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• 1996

In this paper, we propose a hybrid blind equalizer with TEA and SG (stop & Go) algorithm with switching point a 0 dB of MSE value for improvement of convergence performance, where TEA is used initially to open the eye and then SG algorithm as rapid convergence is employed. The switching point is selected at the point of 0 dB MSE level because of settling the coefficients of blind equalier. As a result of computer simulatons for 8-PAM in the non-minimum phase channel, the proposed algorithm has better convergence speed as 3,500 ~ 4,500 iterations and has better MsE about 3 ~ 6 dB than those of original TEA. Also, computational cost of proposed algorithm is reduced as 5 ~ 16% than that of original TEA. and, the proposed algorithm has better convergence than SG algorithm as 8,500 ~ 17,500 iteratins but, the MSE is similar to original SG.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.11
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• pp.1651-1658
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• 2013

Nitrate contamination in ground and surface water is an increasingly serious environmental problem and only a few bacterial strains have been identified that have the ability to remove nitrogen pollutants from wastewater under thermophilic conditions. We therefore isolated thermophilic facultative bacterial strains from wood chips that had been composted with swine manure under aerated high temperature conditions so as to identify strains with denitrifying ability. Nine different colonies were screened and 3 long rod-shaped bacterial strains designated as SG-01, SG-02, and SG-03 were selected. The strain SG-01 could be differentiated from SG-02 and SG-03 on the basis of the method that it used for sugar utilization. The 16S rRNA genes of this strain also had high sequence similarity with Geobacillus thermodenitrificans $465^T$ (99.6%). The optimal growth temperatures ($55^{\circ}C$), pH values (pH 7.0), and NaCl concentrations (1%) required for the growth of strain SG-01 were established. This strain reduced 1.18 mM nitrate and 1.45 mM nitrite in LB broth after 48 h of incubation. These results suggest that the G. thermodenitrificans SG-01 strain may be useful in the removal of nitrates and nitrites from wastewater generated as a result of livestock farming.

• Review of KIISC
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• v.28 no.4
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• pp.6-12
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• 2018

국제전기통신연합(ITU)은 UN 산하 정보통신기술에 대한 국제표준을 담당하고 있으며, 전기통신표준화부문(ITU-T), 전기통신개발부문(ITU-D), 그리고 전파통신 부문(ITU-R)으로 구성되어 있다. ITU-T는 역할과 임무에 따라 11개의 연구반 (SG, study group)으로 구성되어 있고, 정보통신 환경에서 사용되는 정보보호 국제표준은 ITU-T SG17(보안, 의장: 순천향대 염흥열 교수)에서 담당하고 있다. 본 논문에서는 2018년 3월 스위스 제네바에서 개최된 SG17 국제회의 주요 결과 및 향후 전망에 대해 분석하고자 한다.

• Review of KIISC
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• v.30 no.4
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• pp.7-16
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• 2020

국제전기통신연합(ITU)은 UN 산하 정보통신기술에 대한 국제표준을 담당하고 있으며, 전기통신표준화부문(ITU-T), 전기통신개발부문(ITU-D), 그리고 전파통신 부문(ITU-R)으로 구성되어 있다[1]. ITU-T 산하에는 역할과 임무에 따라 11개의 연구반(SG, Study Group)을 구성하고 있으며, SG17(보안, 의장: 순천향대 염흥열 교수)에서 정보보호 국제표준을 담당하고 있다[2]. 본 논문에서는 최근에 개최된 SG17 국제회의(2019년 8월, 2020년 3월/5월)의 주요 결과 및 향후 전망에 대해 분석하고자 한다.

• Nuclear Engineering and Technology
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• v.53 no.5
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• pp.1446-1453
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• 2021

In the past, several experimental investigations aiming at characterizing the natural circulation (NC) behavior in test facilities were carried out. They showed a variety of flow patterns characterized by an inverted U-shape of the NC flow curve versus primary mass inventory. On the other hand, attempts to reproduce such curves using thermal-hydraulic system codes, showed 10-30% differences between the measured and calculated NC mass flow rate. Actually, the used computer codes are generally based upon nodalization using single U-tube representation. Such model may not allow getting accurate simulation of most of the NC phenomena occurring during such tests (like flow redistribution and flow reversal in some SG U-tubes). Simulations based on multi-U-tubes model, showed better agreement with the overall behavior, but remain unable to predict NC phenomena taking place in the steam generator (SG) during the experiment. In the current study, the CATHARE code is considered in order to assess a NC characterization test performed in the four loops PKL facility. For this purpose, four different SG nodalizations including, single and multi-U-tubes, 1D and 3D SG inlet/outlet zones are considered. In general, it is shown that the 1D and 3D models exhibit similar prediction results up to a certain point of the rising part of the inverted U-shape of the NC flow curve. After that, the results bifurcate with, on the one hand, a tendency of the 1D models to over-predict the measured NC mass flow rate and on the other hand, a tendency of the 3D models to under-predict the NC flow rate.

• Review of KIISC
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• v.31 no.4
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• pp.7-15
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• 2021

국제전기통신연합(ITU)은 UN 산하 정보통신기술에 대한 전문 국제표준화기구이다. 193개 회원국, 약 900개 기업 및 학교 멤버 등으로 구성되어 있으며, 산하에 전기통신표준화부문(ITU-T), 전기통신개발부문(ITU-D), 그리고 전파통신 부문(ITU-R) 등 3개의 부문으로 구성되어 있다[1]. ITU-T는 역할과 임무에 따라 11개의 연구반 (SG, study group)으로 구성되며, 각 업무에 맞는 선도 그룹(Lead Study Group)을 지정하여 국제표준을 개발하고 있다. 정보보호 국제표준은 ITU-T SG17(보안)에서 담당하고 있다[2]. ITU-T 국제표준화 조직은 4년 주기의 연구회기(Study Period)로 연구반 구조조정, 의장단 선출 및 표준화 추진 방향을 WTSA(World Telecommunication Standardization Assembly) 총회에서 결정한다. 2020년 11월에도 WTSA-20 총회가 개최될 예정이었으나, 코로나19로 총회가 2022.3월로 연기되었다. 본 논문에서는 WTSA-20 총회가 연기됨에 따라 기존 연구회기(2017.1-2020.12)의 연장인 추가 연구회기(2020.11-2022.2) 동안에 ITU-T SG17 의장단과 연구반 내에 구조조정 결과에 대해 정리하고, SG17 국제표준화 현황을 다룬다.

• Review of KIISC
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• v.27 no.5
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• pp.5-13
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• 2017

국제전기통신연합(ITU)은 UN 산하 정보통신기술에 대한 전문 국제기구이다. 193개 회원국으로 구성된 국제전기통신연합은 산하에 전기통신표준화부문(ITU-T), 전기통신개발부문(ITU-D), 그리고 전파통신부문(ITU-R) 등 3개의 부문으로 구성되어 있다[1]. ITU-T는 역할과 임무에 따라 11개의 연구반 (SG, study group)으로 구성되며, 각 업무에 맞는 선두 그룹(Lead Study Group)을 지정하여 표준을 개발하고 있다. 정보보호 국제표준화는 ITU-T SG17(보안)에서 담당하고 있다. ITU-T 국제 표준화는 4년 주기의 연구회기(Study Period)로 연구반 구조를 조정하며, 표준화 방향도 결정된다. 이러한 표준화 방향을 결정하기 위한 회의가 2016년 튀니지에서 열린 WTSA-16 (World Telecommunication Standardization Assembly) 총회이다. 본 논문에서는 WTSA-16 총회에서 결정된 ITU-T SG17 의장단과 정보보호 국제표준화 활동과 관련된 WTSA-16 결의(Resolution)를 분석하고, 2017년 두 차례 SG17 회의에서 추진된 SG17 구조와 추가 의장단 구성을 포함하는 표준화 동향을 제시한다.