• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.3
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• pp.205-213
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• 2022

The experimental fish transplanted from China in 2015 was used after seedling production and cultivated. Breeding management for experiment was carried out from October 2020 to February 2021. Also, it succeeded in inducing artificial maturation three to four months earlier than wild broodstock and secured good quality fertilized eggs. The average size of fertilized eggs was 1.22 mm, at 20℃ Blastodisc (15 minutes post-fertilization), 2 cell (50 minutes), 4 cell (1 hours), 8 cell (2 hours), 16 cell (2 hours and 30 minutes), 32 cell (2 hours and 50 minutes), morula (3 hours), blastula (8 hours), gastrula (15 hours), skull formation (20 hours), organ formation (30 hours) and hatching yolk larvae stage (35 hours). The total length of the just hatched larvae were 2.50 ± 2 mm, and then gain growth of 42.5 mm by 60 days, reaching 45 ± 5 mm.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.110-110
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• 2021

사회적, 환경적으로 크고 작은 문제를 일으키는 녹조현상은 수생태계에서 1차 생산자로 없어서는 안 될 조류의 과대 성장으로 인해 주로 나타난다. 담수조류는 크게 녹조류, 남조류, 규조류 3종으로 나누어지며, 특히 남조류는 계절별 천이에 따른 발생 시 과대 성장하는 특성으로 인해 녹조현상에 가장 큰 원인이 된다. 이러한 녹조현상의 원인에 따라 환경부에서는 발령기준 항목을 chl-a와 남조류 세포수에서 2016년 이후 남조류 세포수 만으로 발령기준 항목을 개정하였다. 따라서, 녹조현상에 대한 신속한 대처를 위해서는 남조류에 대한 분포에 대해 파악하는 것이 가장 우선시 되며 이를 위해 신속한 모니터링을 필요로 한다. 하지만 현재 조류 모니터링을 위해서는 직접 채수를 통한 검경 또는 Lisst, YSI와 같은 직접 계측 센서를 활용하여 모니터링을 진행을 하고 있으며 이러한 점, 선 단위의 측정은 전반적인 조류 분포 및 현황에 대하여 파악과 신속한 모니터링에 한계가 있다. 이러한 한계에 대안으로 위성영상, 다중분광 및 초분광 영상을 활용한 면단 위의 원격 모니터링을 통해 신속하고 하천 내 전반적인 조류 농도 분석을 위한 연구가 다양하게 진행되고 있다. 본 연구에서는 UAV를 활용한 초분광센서를 이용하여 하천과 일정한 반사율을 가지는 반사천을 촬영하고 취득한 초분광영상 보정 및 분석을 진행하였다. 최적 밴드 비를 산정하고 YSI를 통한 Chl-a 결과를 이용하여 분광 특성별 맵핑을 통한 공간적 분포의 조류 농도를 산정하고자 한다.

• Korean Journal of Ecology and Environment
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• v.34 no.1 s.93
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• pp.45-53
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• 2001

Transport of cyanobacterial toxins (microcystin-LR, -RR, -YR) were assessed from a eutrophic lake, Lake Suwa, through the outflowing river, the Tenryu River, and its irrigation channel branch. Temporal variation of phytoplankton species composition in the river coincided with those of the lake; Microcystis ichthyoblabe dominated from June to July, and M. viridis dominated from August to September. When cyanobacterial bloom occurred, microcystins were continuously detected at the concentration of $0.3{\sim}3.2\;{\mu}g/l$ even at 32 km downstream. The change of the content of three microcystin variants were related both with the total cell density of Microcystis and with the change of Microcystis species composition. When Microcystis ichthyoblabe dominated during July, only microcystin-RR (MC-RR) and -LR (MC-LR) were detected, while when Microcystis viridis dominated between August and October, microcystin-RR,-YR (MC -YR) and -LR were detected. Along 29 km flowing distance (flow time 11 hours) between site 2 and site 5 in the Tenryu River, cyanobacterial density and microcystin concentration were reduced by 73% and 72%, respectively, which is mostly contributed by the dilution effect of tributary waters (61% and 57%, respectively) . In the artificial irrigation channel microcystins and cyanobacterial cells were decreased less than in the natural river. The results indicate that cyanobacterial toxins can be transported far downstream without much removal and give hazards to water usage in downstream of eutrophic lakes with cyanobacterial blooms.

• Journal of Korean Home Economics Education Association
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• v.18 no.3 s.41
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• pp.119-131
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• 2006

The purpose of this study was to investigate the body size perception and appearance management behaviors of middle school boys and girls. Subjects of this study were 7 coeducational middle school boys and girls in Gwangju and 435 responses were collected from real body measurement and questionnaires. SPSS package 12.0(Kr) was used to analyze results. The results were summarized as follows: First, middle school boys and girls tended to perceive their bodies slimmer as well as obeser. It is recommended to give education for correct perception of their body sire. Second, the correlation of body size perception factor and appearance management behavior was Middle school boys and girls tended to manage their appearance using a diet rather than doing exercise in obesity distortion perception group(the group perceive obeser than real body size). It needs to be properly guided. Third, the appearance management behavior of slimness distortion perception group(the group perceive slimmer than real body size) and normal group was examined. While middle school boys did only exercise management, middle school girls did all but exercise management. Their education should be distinguished. Finally, while slimness distortion perception group did diet management in both middle school boys and girls, they tended not to manage body correction or exercise. A tendency to depend only on a diet in the group who should perceive their need of exercise should be corrected. In order to correct the distorted body perception and appearance management behavior of middle school boys and girls, it is recommended to educate a standard body size through home management education which is a regular curriculum, and at the same time to guide them to perceive their actual body size correct.

• Korean Journal of Family Social Work
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• no.54
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• pp.107-153
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• 2016

The purpose of this study was to explore the marriage decision-making process and experience of the 'Older women-Younger men couple' and presenting a substantive theory to explain the decision-making process that married women experience of 'Older women-Younger men couple'. This in-depth interviews were conducted 11 female people among 32-48 years of 'Older women-Younger men couple.' Analysis of the data was applied to the "grounded theory" method of Qualitative research methods suggested by Strauss and Corbin(1998). Research questions of this study is that what is the experience of the marriage decision-making process to 'Older women-Younger men couple?'. After analyzing the data to the grounded theory method 75 concepts and 29 sub-categories, 14 categories were derived. Older women experienced a central phenomenon of 'ambivalence of love and anxiety'.'Older women-Younger men couple's marriage decision-making process of the women had to 'step adjustment', 'acceptable level', 'Step enacted', and 'Older women-Younger men couple's core category of married women in the decision-making process' was 'Intimacy based on the trust each other beyond the prejudices of the differences'. This study is meant by presenting the basic data provided professional counseling intervention measures for 'Older women-Younger men' couple by collectively Understanding the decision-making process of Older women-Younger men couple married.

• Korean Journal of Comparative Education
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• v.28 no.3
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• pp.217-242
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• 2018

This study was conducted to compare and analyze the curriculum of early childhood education in South Korea and North Korea in order to establish the direction of early childhood curriculum. Based on this, the purpose of the study is to propose educational alternatives for possible integration. The comparison of North and South Korean early childhood education curriculum was conducted in terms of educational goals, early childhood curriculum area and daily management, teaching and learning methods, and assesment. As a result of the study, there were more differences found than similarities in various areas due to differences in the educational philosophy between South and North Korea, and the following implications were drawn. First, in order to integrate North and South Korea's early childhood curriculum, a new educational ideology that reflects the unique function and purpose of education should be established first, and specific curriculum and contents should be developed accordingly. Second, the most significant difference in the content and operation of North and South Korean early childhood education curriculum is political ideology education, which is the most important content of the North Korean early childhood education course. Third, in order to integrate the South and North Korea early childhood education curriculum in preparation for unification, it is necessary to organize and standardize the terms related to early childhood education in order to unify them. In order to do this, it is necessary to try to integrate them gradually starting from areas showing similarities, and to endeavor to overcome discrepancies through mutual exchange between South and North Korea.

• Journal of Korea Water Resources Association
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• v.49 no.9
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• pp.789-798
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• 2016

Frequent algal blooms at major river systems in Korea have been serious social and environmental problems. Especially, the appearance of cyanobacteria with toxic materials is a threat to secure a safe drinking water. In order to model the behaviour of cyanobacteria cell number, an exclusive causality analysis using prewhitening technique was introduced to delineate effective parameters to predict the cell numbers of cyanobacteria in Seungchon Weir and Juksan Weir along Youngsan river system. Both input and output transfer function models were obtained to explain temporal variation of cyanobacteria cell number. A threshold behaviour of water temperature was implemented into the model development to consider winter characteristic of cyanobacteria. The implementation of water temperature threshold into the model structure improves the predictability in simulation. Even though the input output transfer model cannot completely explained all blooms of cyanobacteria, the simple structure of model provide a feasibility in application which can be important in practical aspect.

• Korean Journal of Veterinary Service
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• v.43 no.4
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• pp.211-216
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• 2020

Coxiella burnetii is the causative agent of Q fever which is a zoonosis occuring in both humans and animals worldwide. The purpose of this study was to investigate the seroprevalence of C. burnetii in Korean native goat in Gyeongnam province, Korea. A total of 1,365 goat blood samples from 273 farms in Gyeongnam province were collected between 2018 and 2019. Among them, 177 (13.0%) samples out of 71 (26.0%) farms were seropositive for C. burnetii by ELISA. Seroprevalence were 15.4% and 10.9% in 2018 and 2019, respectively. According to the region, seroprevalence in western, central, eastern, northern and southern areas of Gyeongnam province were 16.6%, 17.8%, 8.0%, 11.6% and 10.8%, respectively. Seroprevalence was increased with breeding scale (Head<10:7.0%, 10≤Head<50:8.7%, 50≤Head<100:13.6%, 100≤Head:28.8%). Seroprevalence according to the season showed highest in summer (18.9%) and lowest in winter (9.4%). These results indicated that C. burnetii infection is widespread among Korean native goats of Gyeongnam province in Korea and further study needs to prevent the circulation of other livestock with Korean native goat.

• Journal of agriculture & life science
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• v.50 no.4
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• pp.225-234
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• 2016

This study aimed at analyzing the economic value of 'Fuyu' sweet persimmon. For the analysis, the raw data of the latest 9 years were collected from 707 farmers in major sweet persimmon area and from 47 farmers surveyed in the field. These data include receipt price per kilogram, costs, yields per tree, etc. The findings are as follows: The break-even tree age of sweet persimmon was 85 years. The trees reach the maximum harvest at age of 65. 'Fuyu' sweet persimmon's economic value was 10,488 thousand won in income approach, 9,249 thousand won in cost approach, respectively.

• Analytical Science and Technology
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• v.22 no.2
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• pp.119-127
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• 2009

This study was carried out to investigate the distribution characteristics of persistent organic pollutants in incineration residues at industrial waste incinerators and municipal solid waste incinerators, which were analyzed by the official analytical method for the endocrine disrupting chemicals and the waste. Seven of 12 persistent organic pollutants were quantitatively analyzed by GC-MSD (SIM-mode). Hexachlorobenzene was detected in 21 samples among 44 incineration residues. The level of hexachlorobenzene was 0.132-8.138 ng/g in incineration residues, 0.195-5.765 ng/g in fly ash at industrial waste incinerators, 0.270-1.828 ng/g in bottom ash and 0.154-50.643 ng/g in fly ash at municipal solid waste incinerators, respectively.