• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.50-56
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• 2020

Determination of the precise size at sexual maturity is very important for science-based stock assessment and fisheries resource management. In this study, two different models, (1) a visual method and (2) a gonadosomatic index (GSI) method, were employed to estimate length at sexual maturity of the small yellow croaker Larimichthys polyactis in the Yellow Sea of Korea. The visual method is a common qualitative method using visual gonadal identification. Conversely, the GSI method is a quantitative method using the GSI, which can be easily and precisely collected. We compared results from these methods to determine the best approach, and to examine the practicality of the GSI method. Logistic regression of the maturity ogive was conducted using a general linear model (GLM) with the R statistics program. Also, the bootstrapped 95% confidence intervals of all estimates were calculated. The best-fit model was the visual method (R_Mc²=0.805, AUC=0.989, L₅₀=15.1). Among models using the GSI method, the model computing GSI_ref=0.94 was the best-fit model (R_Mc²=0.792, AUC=0.989, L₅₀=15.2). There was no significant difference between the two models, evidencing the effectiveness and accuracy of the GSI method.

• Journal of the Economic Geographical Society of Korea
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• v.17 no.4
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• pp.786-800
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• 2014

The aim of this article is to analyze the relationship between the change of the diversity of the industrial structure, and regional employmentability and the intensification of regional competitiveness, and consequently, is to present policy implications. As a result of the analysis of the whole industry such as the primary, secondary and tertiary industry in Chungnam Province, the existing strategic implementation on the employmentability and regional competitiveness throughout the policy on the existing specialized industries can be regarded as appropriate. However, under the condition that danger and stability in each industry are fluctuated and the internal and external circumstances are varied, the detailed analysis and rapid policy prescription on the primary and tertiary industry are required. Along with these results, policy implications are as follows; Firstly, in terms of effectiveness, regional policy are simultaneously conducted along with industrial, technological and regional development's policies while consider ing complex and comprehensive characteristics of the regional industry and rapid changing the global market conditions. Secondly, with respect to equity, regional policy is needed to implement by reducing the socio-economic gap across regions and mixing regional and sectoral policies along with regional and local uniqueness.