• Journal of Biosystems Engineering
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• v.41 no.3
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• pp.273-280
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• 2016

Purpose: This experiment was conducted to detect water stress in terms of the moisture content of cucumber seedlings under water stress condition using a hyperspectral image acquisition system, linear regression analysis, and partial least square regression (PLSR) to achieve a non-destructive measurement procedure. Methods: Changes in the reflectance spectrum of cucumber seedlings under water stress were measured using hyperspectral imaging techniques. A model for estimating moisture content of cucumber seedlings was constructed through a linear regression analysis that used the moisture content of cucumber seedlings and a normalized difference vegetation index (NDVI). A model using PLSR that used the moisture content of cucumber seedlings and reflectance spectrum was also created. Results: In the early stages of water stress, cucumber seedlings recovered completely when sub-irrigation was applied. However, the seedlings suffering from initial wilting did not recover when more than 42 h passed without irrigation. The reflectance spectrum of seedlings under water stress decreased gradually, but increased when irrigation was provided, except for the seedlings that had permanently wilted. From the results of the linear regression analysis using the NDVI, the model excluding wilted seedlings with less than 20% (n=97) moisture content showed a precision ($R^2$ and $R^2_{\alpha}$) of 0.573 and 0.568, respectively, and accuracy (RE) of 4.138% and 4.138%, which was higher than that for models including all seedlings (n=100). For PLS regression analysis using the reflectance spectrum, both models were found to have strong precision ($R^2$) with a rating of 0.822, but accuracy (RMSE and RE) was higher in the model excluding wilted seedlings as 5.544% and 13.65% respectively. Conclusions: The estimation model of the moisture content of cucumber seedlings showed better results in the PLSR analysis using reflectance spectrum than the linear regression analysis using NDVI.

• Korean Journal of Ichthyology
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• v.24 no.2
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• pp.131-134
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• 2012

A single specimen of Cyclopteropsis bergi, belonging to Cyclopteridae, Scorpaeniformes, was newly collected from Sokcho, Korea in May 2011. C. bergi is characterized by tip of 1st dorsal fin spines visible, scattered bony tubercles on body, and head without bony tubercles. New Korean name of Cyclopteropsis bergi is proposed as "kko-ma-do-chi".

• Korean Journal of Ichthyology
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• v.23 no.1
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• pp.75-79
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• 2011

This study was conducted to investigate protocol standardization for cryopreservation spermatozoa of the bar-tailed flathead Platycephalus indicus. The suitability of the cryoprotectants, dimethyl sulphoxide (DMSO), glycerol and methanol were tested against three freezing rates and three thawing temperatures. DMSO and glycerol gave significantly higher motile index and survival rates than methanol. Among the freezing rates, freezing at a height of 2 cm above $LN_2$ surface for $10\;min^{-1}$ gave higher motile index and survival rates. In terms of best thawing temperature, $20^{\circ}C$ obtained the highest motility.

• Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.3.1-3.8
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• 2019

The purpose of this study is to investigate the changes in growth, hematological parameters, and plasma components of juvenile starry flounder, Platichthys stellatus, following exposure to varying arsenic concentrations present at different water temperatures. P. stellatus (total length, $15.9{\pm}0.4cm$; body weight, $62.2{\pm}4.2g$) were exposed for 4 weeks to waterborne arsenic (sodium arsenite, As) at 0, 150, 300, and $600{\mu}g/L$ at temperatures of $12^{\circ}C$ and $18^{\circ}C$. Toxic effects of As exposure on P. stellatus were higher at the higher temperature and the growth and hematological parameters measured decreased with increasing arsenic concentration, while the concentration of plasma components measured increased. This indicates that waterborne As exposure and water temperature can cause toxic effects on growth, hematological parameters, and plasma components in Platichthys stellatus.

• The Journal of Fisheries Business Administration
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• v.47 no.3
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• pp.93-110
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• 2016

Most of the changes that make paradigm shift have been involved international level problems related to environment, resource and structure problems in these days. Resolving those common issues the United Nations Food and Agriculture Organization(UN FAO) has played most important role in fisheries with publishing the series of the technical guidelines for responsible fisheries papers. The guidelines for responsible fisheries have introduced for applying the concept of sustainable development with considering overall changes in fisheries domains. And also have objectives that establishing the discipline of fisheries worlds. Although these papers are remarkable, there is still few research or education contents of them in Korea. Fisheries business administration is a kind of social science that influenced by environmental, social changes so called paradigm shift. So one of the most important thing that has the education of sustainable development is accommodation or adaptation of them with grasping the phenomenon continuously. The aims of this study are exploring the FAO's the technical guidelines for responsible fisheries documents and contents of college's fisheries business administration and finding out the overall systematic topics and themes of fisheries business administration education. The result of this study shows that the contents of fisheries business administration did not including the concept of responsible fisheries even were out of date in using statistical data. And there is some missing issues that including fisheries policy, resource management, and related law should be enhanced. This study suggests the framework of fisheries business administration with comparing analysis on FAO's document and college's course of study in Korea. The proposed framework of major topics of fisheries business administration that still needed to be improved should be a milestone of understanding and debating the core factors of fisheries business administration education and research.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.4
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• pp.1099-1108
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• 2015

The purpose of this study is to develop a feasible and reliable tool to diagnose human's core dynamic. For this, 40 questions were developed based on literature analysis and interviews and through Delphi survey and validity and reliability analysis, an investigation tool comprised of 30 questions in 8 areas were developed finally. The investigation tool developed in this study can be utilized in measuring the obstacles and negativity that obstruct changes in individuals and in particular, it is expected to be useful in discovering obstacles that obstruct the development of members in actual organizations and resolving them. Moreover, this investigation tool can also be utilized in coaching organizations and individuals, mentoring and consultation.

• Korean Journal of Organic Agriculture
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• v.27 no.2
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• pp.111-132
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• 2019

Recently farming succession has become an important topic in agriculture in order to secure agricultural manpower in response to the aging of farming households and declining population. This study investigates farmers and agricultural college students' perception of farming succession in Korea, especially of farming succession to a third party. Farmers and agricultural college students are potential farming transferors and successors, respectively. We surveyed 146 farmers and 95 students who graduated or were studying at the Korea National College of Agriculture and Fisheries. The questions of the survey are largely divided into four categories: 1) the will and scope of farming transfer and succession, 2) the requirements for the successors of farming, 3) the perception on the succession to third-parties, and 4) the farming succession policy. According to the survey results 41.4% of farmers and 46.3% of potential farming successors have willingness to accept a farming succession to a third party. When farming succession was carried out through the Farming Succession Exchange, 46.8% of farmers and 54.7% of successors said they are willing to carry out third-party farming succession. This means that a third-party farming succession could be activated if the reliability issue that may arise during the farming succession is resolved through the Farming Succession Exchange. Other implications for farming succession are suggested at the end of this study.

• Korean Journal of Environmental Biology
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• v.33 no.4
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• pp.433-440
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• 2015

The Apostichopus japonicus is an important species in some Asia countries including Korea, China and Japan. The purpose of the present study was to investigate the differential gene expression of heat shock protein90 (Hsp90) and ferritin as a biomarker for the thermal stress during water temperature rising in the sea cucumber, A. japonicus. The A. japonicus (1.4 g) was cultured in incubator of separate temperature ($15^{\circ}C$, $20^{\circ}C$, $25^{\circ}C$ and $30^{\circ}C$) for each 0, 3, 6, 12, 24, 48 hours. The mRNA expression levels of Hsp90 and ferritin were examined using RT-PCR assay. Results showed that, the expression of Hsp90 mRNA was not significantly changed at $15^{\circ}C$. The expression of Hsp90 mRNA was significantly increased at high temperature such as $20^{\circ}C$ and $25^{\circ}C$. Furthermore, Hsp90 mRNA was early increased at $25^{\circ}C$ than $20^{\circ}C$. The ferritin mRNA was similar expression pattern with Hsp90. But, Hsp90 mRNA was more sensitive than ferritin mRNA at high thermal stress. These results indicate that Hsp90 and ferritin mRNAs were involved in the temperature changes response and may be play an important role in mediating the thermal stress in A. japonicas.

• Journal of fish pathology
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• v.23 no.1
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• pp.85-98
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• 2010

Ministry of Agriculture, Fisheries and Food (MAFF) and National Fisheries Research and Development Institute (NFRDI) have inspected the hatchery-reared seeds of 22 marine species and 11 freshwater species for aquatic animal diseases in stock enhancement program in 2009. Results showed that total 12 local selfgovernments have been restocking the sea with cultured juveniles. Gyeongsangnam-do, Jeollanam-do, Jejudo and Chungcheongnam-do have a preference for marine species seeds to freshwater species. On the contrary, freshwater species were released mostly in Gyeonggi-do, Jeollabuk-do and Chungcheongbuk-do. In the marine species group, abalone was the most abundant as 24.5%, and then sea cucumber (15.2%), olive flounder (11.5%), swimming crab (5.6%), black sea bream and rockfish (6.8%), rock bream (5.1%), black rockfish (4.6%) and scorpionfish (4.5%) were followed. Crucian carp was the most abundant as 19.4%, and then eel (17.0%), Korean bullhead (12.3%), melanian snail (12.0%), catfish (8.4%) were followed in the freshwater species group. The total number of inspection cases in this study were 1,080 and disqualification cases were 19 by detection of aquatic animals pathogens such as red sea bream iridovirus (RSIV), koi herpesvirus (KHV) or white spot syndrome virus (WSSV).

• The Journal of Fisheries Business Administration
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• v.53 no.3
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• pp.85-101
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• 2022

This study analyzed the performance of the national fishing port development project, which lacked ex-post impact evaluation despite a lot of investment in terms of fishery income opportunities. Using micro data from the Census of Agriculture, Forestry, and Fisheries, the sales amount of fishery products and the proportion of fishery-related businesses were used as performance indicators. The fishery households in the fishing port area (treatment group) and those not in the area (control group) were classified through data pre-processing, and factors unrelated to the fishing ports were controlled using the propensity score matching difference-in-difference method. The analysis target is six fishing ports with large investment in from 2010 to 2014. As a result of the analysis, it was confirmed that the sales of fishery products increased significantly in four of the six fishing ports, and the proportion of fishery-related businesses increased in two fishing ports. The analysis method of this study can be fully utilized in the evaluation of the Fishing Community New Deal 300 Project, which is in need of performance analysis.