• Journal of Aquaculture
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• v.9 no.3
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• pp.287-291
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• 1996

[ $F_2$ ] generation of gynogenetic diploids were produced in olive flounder, Paralichthys olivaceus, by brother-sister mating with full-sibling gynogenetic diploids ($F_1$). The induced ovulations and spawnings were conducted by using intraperitoneal injections of HCG (2,000 IU/kg body weight) with photoperiod controls. Floating rates of artificially ovulated eggs were ranged from 22.9 to $65.7\%$. Fertilization and hatching rates were ranged from 69.0 to $86.2\%$ and 36.8 to $85.8\%$, respectively. All of those three rates between two experimental groups were not significantly different (P>0.05). Average survival rates of $F_2$ generation of 40-day-old 효nogenetic diploid larvae were slightly lower than those of controls (P<0.05), however growth rates were much higher than those of their diploid controls.

• Research in Plant Disease
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• v.10 no.4
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• pp.279-284
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• 2004

A rust fungus has caused a serious early defoliation of Zanthoxylum schinifolium during growing seasons every year at the plantations located at Hadong and Jinju, Kyeongsangnam-Do in Korea. In order to identify the rust fungus and clarify its life cycle in Korea, aeciospores from Pinus thunbergii were artificially inoculated on the leaves of Z. schinifolium. Uredinial stage was successively formed on the leaves of Z. schinifolium. Based on the artificial inoculation test and on the morphological features of the dried specimens collected from P. thunbergii and Z. schinifolium, this rust fungus was identified as Coleosporium xanthoxyli. Morphological features of aecial and uredinial stages of the species were described. The first symptom of the infection was developed from later June to early July. And leaf infection ratio was 17.8%-58.7% during August at Hadong and Jinju regions of Kyeongsangnam-Do in Korea.

• Land and Housing Review
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• v.6 no.4
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• pp.231-237
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• 2015

Recently, It has been much interest in modular housing construction. so, The purpose of this study was to investigate the characteristics of the indoor air quality in modular mock-up housing. We measured indoor air quality(formaldehyde, benzene, toluene, ethylbenzene, xylene, styrene) of two modular mock-up units that built-in furniture is installed and uninstalled. As a result, the pollutants of built-in furniture installed unit were emitted more than built-in furniture uninstalled unit. But after bake-out and ventilation, emission concentrations of two modular mock-up units were similar and were below Indoor Air Quality recommendation standards. Built-in furniture is likely to affect the emission concentration of toluene

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.26-33
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• 2004

Self-etching priming bonding system was recently developed in order to simplify the clinical skills & save chair time after continuous improvements on dentin bonding agents. To test the magnitude of microleakage of a new "self-etching priming bonding agent" using sound premolar 4th, 5th, 6th generation dentin bonding agent was applied. Measure the magnitude of infiltration to the gap of enamel-restoration interface and dentin-restoration interface. After bonding of composite resin to sample surfaces according to the manufactures direction and 500 times thermocycling on dwell time 30 second, and microleakage was measured by the ratio of the depth to the axial wall and the magnitude of infiltration. Afterward analyzed by ANOVA test. The result were as follows ; 1. Enamel groups showed lesser microleakage (Group I, II, III, IV) than dentin groups(Group V, VI, VII, VIII). (p<0.05) 2. There are no statical differences among the dentin groups, in enamel groups, group IV showed more microleakage than group I, II, III. (p<0.05). For a clinical acceptance, better enamel marginal adaptation is required.

• Fire Science and Engineering
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• v.20 no.1 s.61
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• pp.98-103
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• 2006

This paper analyzed deaths caused by fires using the Annual Report on the Cause of Death Statistics (based on vital registration) published by the Korea National Statistical Office. The number of fire deaths and the fire death rates of all deaths have started to decrease since the height in 1993. The younger groups have increasingly more fire deaths than the older groups. While children groups(age 10 and under) have decreased in their deaths caused by fires, the older groups (65 and over) tend to increase. Males are more likely to have a risk than females in all age groups. Fire death rates per 100,000 populations by age group suggest very high rates in the older groups. Although there are few changes in death rates caused by fires of all deaths, young children (age 4 and under) and older adults (age 75 and over) have a higher risk than any other age groups.

• The Journal of the Korea Contents Association
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• v.16 no.4
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• pp.666-674
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• 2016

This study examines the effect of consumption level on the life satisfaction of baby-boom generation and further examines the mediating effect of subjective expectation(standard of living and government policy). This research uses the panel survey to explore ageing society in 2012 made by Korean Labor Institute, which studied 1,756(born in 1955~1961). SPSS 21.0 Package was applied to analyze the date and multi-regression analysis was conducted. As a result, first, the findings show that as the consumption level increases, the life satisfaction of the baby-boom generation goes up. Second, the findings reveal that subjective expectation partially mediates the influences of consumption level on the life satisfaction of baby-boom generation. This study further discusses the theoretical and political implication of the direction properties on baby-boomer based upon the results of the study.

• Journal of Broadcast Engineering
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• v.13 no.4
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• pp.463-478
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• 2008

A Distributed Translator Network(DTxR) is a cost-effective and frequency-effective method which can use existing transmission utilities and can be constructed in a shorter time as compared with Multiple Frequency Network(MFN) or Single Frequency Network(SFN) using On Channel Repeater(OCR). In order to verify the feasibility of DTxR, this field test was done in 30 points of north-west area in Seoul using 3rd, 5th, and 6th generation DIV receivers. Electric field strength, noise margin and ease of reception were measured and subjective evaluation of video quality was done in these points during the field test. With the test result, an improvement of receiving quality was obtained and an ease of reception was increased in case of the 5th. and 6th. receiver. From the results, we conclude that DTxR is a feasible method in DIV networks.

• KIPS Transactions on Software and Data Engineering
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• v.9 no.11
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• pp.351-356
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• 2020

With the spread of COVID-19 infections, the need for next-generation learning management system for undact education is rapidly increasing, and the Ministry of Education is planning future education through the establishment of fourth-generation NEIS. If the fourth-generation NEIS System is well utilized, there are advantages such as providing personalized education services and activating the use of educational data, but a solution to the illegal access problem in an access control environment where strict authorization is difficult due to various user rights. In this paper, we propose a blockchain-based access control audit system for next-generation learning management. Sensitive personal information is encrypted and stored using the proposed system, and when the auditor performs an audit later, a secret key for decryption is issued to ensure auditing. In addition, in order to prevent modification and deletion of stored log information, log information was stored in the blockchain to ensure stability. In this paper, a hierarchical ID-based encryption and a private blockchain are used so that higher-level institutions such as the Ministry of Education can hierarchically manage the access rights of each institution.

• Korean Journal of Plant Tissue Culture
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• v.25 no.2
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• pp.103-107
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• 1998

Tobacco proembryos were irradiated with 100 Gy of heavy-ion beams($^{14}\textrm{N}$, $^{20}\textrm{Ne}$: 135 Mev/u) after 24 to 96 hours of pollination as a mutagen and screened $\textrm{M}_{1}$ generation for morphological mutants and salt-tolerant plants. Morphological and physiological characteristics of the salt-tolerant plants derived from the irradiated proembryo are discussed in this report. Mutants irradiated proembryos with the beams after pollination produced various kinds of morphological variation. A total of 17 salt-tolerant plants were selected from tobacco cultivar (BY-4) by treatment with $^{14}\textrm{N}$ beam. Shapes of filament and pollen grain of most salt-tolerant plants were abnormal compared with non-irradiated wild type, and seeds weight and fertility obviously decreased. The germination rates of the several $\textrm{M}_{2}$ lines on the saline and the mannitol condition were higher than that of wild type.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.32 no.4
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• pp.231-263
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• 2021

The purpose of this study is to analyze the information behavior of so-called "MZ Generation" users who are going to be the main information users of the continuously and radically changing scientific information environment due to the advent of various types of information media and rapid increment of digital information resources. Especially, the characteristics of MZ generation is investigated through questionnaire asking questions about their use of contents platforms, and online resources for everyday life information and scholarly information, and their way of producing, responding, and sharing information contents. The results show that they use YouTube most as the contents platform, prefer Naver as their everyday life information source, and use Google as the main scholarly information source. Their main purpose of using the content platform is to search for everyday life information rather than scholarly or professional information, and they are actively producing information, mostly to keep records of their everyday lives.