• Journal of the Korea Institute of Military Science and Technology
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• v.6 no.1
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• pp.91-107
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• 2003

A 2-dimensional search process in the time and frequency domain is required to acquire the GPS signal, when the code phase and the carrier Doppler for the specified GPS satellite signal are unknown. This paper proposes a new scheme, called Squared-D Searching Method, which can reduce the number of carrier frequency candidates, and a new scheme, named extended Multiple Correlator(XMC), which can reduce the number of code phase candidates. The Squared-D Searching Method can take the twice of Doppler frequency, therefore it can find carrier frequency candidates. The XMC is different from the general multiple correlator in that a combined form of the locally generated codes is used for despreading. Also, this paper tries to analyze a signal detection probability of a GPS receiver under more realistic environments. The result shows that lower detection probability can be obtained when the phase differences among the codes are larger in the correlation arms of a multiple correlator. This phenomenon is not easy to explain with the previous results. And besides, the result shows that proposed acquisition schemes give better performance than a conventional acquisition scheme.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.80.2-80.2
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• 2019

We present newly discovered dwarf galaxy candidates in deep wide-field images of NGC 1291 obtained with KMTNet. We initially identify 20 dwarf galaxy candidates through visual inspection. 13 out of 20 appears to be high priority candidates, according to their central surface brightness (${\mu}_{0,R}{\sim}22.5$ to $26.5mag\;arcsec^{-2}$) and effective radii (350 pc to 1 kpc). Structural and photometric properties of dwarf candidates appear to be consistent with those of ordinary dwarf galaxies in nearby groups and clusters. Using imaging simulations, we demonstrate that our imaging data is complete up to $26mag\;arcsec^{-2}$ with > 70% of the completeness rate. In order to find an optimal way to automate detecting dwarf galaxies in our dataset, we test detection methods by varying parameters in SExtractor. We find that the detection efficiency from the automated method is relatively low and the contamination due to the artifacts is non-negligible. Therefore, it can be only applicable for pre-selection. We plan to conduct the same analysis for deep images of other nearby galaxies obtained through KMTNet Nearby Galaxy Survey (KNGS).

• Journal of Contemporary Eastern Asia
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• v.19 no.2
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• pp.197-215
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• 2020

Teaching has become a feminized profession, especially in elementary teaching, in which it is regarded as "women's work." Concerns about the "extinction" of men in the field resulted in calls for male teachers. While studies indicate that there is positive discrimination in favor of men (despite the feminization of teaching), it appears that there are also forms of discrimination that work against them. As such this study explored the challenges of being a male in the feminized profession from the perspective of male teacher candidates. Studies in the field of teacher education in the Philippines mainly focus on curriculum and students' academic achievement, hence an inquiry must be done on the plight of male teachers in a gendered profession. A phenomenological study was employed to look into the realities of six male teacher candidates. Findings show that male teachers are: (1) leadership-destined; (2) conflicted; (3) limited; and (4) devalued. The narrative of male teachers in the Philippine education sector reveals the need to revisit programs and policies in professional development and support. Finally, recommendations are made for teacher education programs to guide teacher candidates' experiences towards a more inclusive profession.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.1
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• pp.57-67
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• 2023

The purpose of this study was to analyze male pilot candidates' life satisfaction, basic psychological needs and grit by experiencing COVID-19 period for pilot literacy education. Participants were 1,249 male pilot candidates (COVID-19 before 613, during 636) were voluntarily participated. The data were gathered from totally 29 question's questionnaire at April 2018 and 2022. Statistical treatment was processed (by SPSS 21.0 for windows) as descriptive and two-way ANOVA for analyzing variables' interaction and main effects. The correlation analysis was processed for analyzing each variable's relations. And the multiple regression analysis was conducted for basic psychological needs' each variables' effect on life satisfaction. Statistical significancy was set as p<.05. The results were as follows. First, variables showed significances (p<.05~.01) by COVID-19 except life satisfaction and competence. Second, correlations showed higher R² value in 2018 than 2022 and significances (p<.05~.01) among all variables, but, passion of grit need to be inspected in subsequent study. Third, multiple regressions showed significancies (p<.05) in all variables in 2018, but, relatedness was excluded in 2022. In conclusion, experiencing COVID-19 period affected pilot candidates' life and it need to be inspected the degree of effect of variables in subsequent study.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.47.1-47.1
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• 2015

We present an optical spectroscopic study of 28 supernova remnant (SNR) candidates in M81 and two SNR candidates in M82. The optical spectra of these SNR candidates were obtained using the MMT/Hectospec as a part of the K-GMT Science Program. Based on the [S II]/$H{\alpha}$ ratio and the radial velocity, we find that twenty six out of the M81 candidates are genuine SNRs. Two SNR candidates in M82 are thought to be shocked condensations in the galactic outflow or SNRs. In the spectral line ratio diagrams, M81 SNRs are divided into two groups: an [O III]-strong group and an [O III]-weak group. The [O III]-weak SNRs have larger sizes, and may have faster shock velocity. We estimate the nitrogen and oxygen abundance of the SNRs from the comparison with shock-ionization models. We find a radial gradient in nitrogen abundance, $dLog(N/H)/dlogR=-0.023{\pm}0.009\;dex\;kpc^{-1}$ little evidence for the gradient in oxygen abundance. The nitrogen abundance shows shallower gradient than those of the planetary nebulae and H II regions of M81. We find five X-ray emitting SNRs. Their X-ray hardness colors are consistent with thermal SNRs.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.22 no.1
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• pp.155-170
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• 2011

The purpose of this study was to analyze whether the promises of library field were, what the promises of candidates were, and whether the content of the promises showed the dissimilar tendency or discrepancy. The starting point of this study was that the library-related issues should be raised in the local election in order that library-related problems in the local area were considered as the policy. The standpoint of this research was based on the notion the library-related problems could be settled if the candidates have an interest in the library field. The range of this research was limited in the election conducted in June 2. 2010. Candidates' promises were collected through a questionnaire, categorized and analyzed by subject. According to the result of analysis, the most candidates had interest in establishing of library infrastructure, on the other hand they had no interest in collection development, library policy, allocation of budget, and job creation for librarian.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.24 no.4
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• pp.153-180
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• 2013

This study explored election promises on library fields by the candidates for the mayor, the educational superintendent and the chiefs of districts of Daegu Metropolitan City and implementation of their election promises by the elected heads of Daegu Metropolitan City in the 5th local election of Korea. To do this, election promises of 36 candidates were analyzed by investigating the official gazettes for elections deposited in National Election Commission of Korea. Also, the implementation of their promises of 11 elected heads was analyzed by searching through the official websites, news databases and internet. As a result, election promises and implementation by the candidates for the mayor and the educational superintendent were mostly insufficient both in quality and in quantity. 54% of all candidates for the chiefs of districts presented election promises that were mostly related with construction of public libraries and installation of small libraries. Some elected chiefs actively implemented their promises, while the other elected chiefs did not fulfill their promises.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.82.1-82.1
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• 2012

We present results of searching for the Very Low Luminosity Objects (VeLLOs; internal luminosity Lint<0.1Lo) candidates in the Gould Belt's clouds using infrared observations from 3.6 to 70 micron by the Spitzer Space Telescope. More than 100 VeLLO candidates were selected through the criteria by Dunham et al. and our additional ones. The candidates in Northern sky were recently observed with high density tracers such as N2H+ (1-0) and HCN (1-0) using Korea VLBI Network (KVN) 21m telescope at Yonsei site to check their embeddedness in dense gas envelopes. A total of 25 out of 74 VeLLO candidates were detected in either N2H+ or HCN (1-0) line while 9 candidates were detected in both tracers. These are more likely bona fide VeLLOs which need to be studied further in future. In this study the bolometric luminosities for 40 VeLLOs (25 from this study and 15 from Dunham et al.) were estimated and found to be significantly smaller than those given by various theoretical model tracks with constant accretion rate in a BLT diagram, indicating the constant accretion process suggested by standard star formation models can not explain the faintness of the VeLLOs. In the talk we will discuss on some possible explanation of why the VeLLOs are faint.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.113-113
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• 2017

Downy mildew (DM), caused by several species in the Peronosclerospora and Scleropthora genera, is a major maize (Zea mays L.) disease in tropical or subtropical regions. DM is an obligate parasite species in the higher plants and spreads by oospores, wind, and mycelium in seed surface, soil, and living hosts. Owing to its geographical distribution and destructive yield reduction, DM is one of the most severe maize diseases among the maize pathogens. Positional cloning in combination with phenotyping is a general approach to identify disease resistant gene candidates in plants; however, it requires several time-consuming steps including population or fine mapping. Therefore, in the present study, we suggest a new combination strategy to improve the identification of disease resistant gene candidates. Downy mildew (DM) resistant maize was selected from five cultivars using the spreader row technique. Positional cloning and bioinformatics tools identified the DM resistant QTL marker (bnlg1702) and 47 protein coding genes annotations. Eventually, 5 DM resistant gene candidates, including bZIP34, Bak1, and Ppr, were identified by quantitative RT-PCR without fine mapping of the bnlg1702 locus. Specifically, we provided DM resistant gene candidates with our new strategy, including field selection by the spreader row technique without population preparation, the DM resistance region identification by positional cloning using bioinformatics tools, and expression level profiling by quantitative RT-PCR without fine mapping. As whole genome information is available for other crops, we propose applying our novel protocol to other crops or for other diseases with suitable adjustment.

• Korean Journal of Veterinary Research
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• v.55 no.2
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• pp.89-95
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• 2015

Johne's disease, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is one of the most widespread and economically important diseases in cattle. Current diagnostic methods are based on the detection of anti-MAP antibodies in serum or isolation of the causative agent. However, these techniques are often not applicable for cases of subclinical infection due to relatively low sensitivity. Therefore, finding new antigen candidates that strongly react with the host immune system had been attempted. To effectively detect infection during the subclinical stage, several antigen candidates were selected based on previous researches. Characteristics of the selected antigen candidates were analyzed using bioinformatics-based prediction tools. A total of nine antigens were selected (MAP0862, MAP3817c, MAP2077c, MAP0860c, MAP3954, MAP3155c, MAP1204, MAP1087, and MAP2963c) that have MAP-specific and/or high immune responses to infected animals. Using a transmembrane prediction tool, five of the nine antigen candidates were predicted to be membrane protein (MAP3817c, MAP3954, MAP3155c, MAP1087, and MAP1204). Some of the predicted protein structures identified using the I-TASSER server shared similarities with known proteins found in the Protein Data Bank database (MAP0862, MAP1204, and MAP2077c). In future studies, the characteristics and diagnostic efficiency of the selected antigen candidates will be evaluated.