2024년 3월부터 2024년 12월까지 충주호 상류에서 채집된 대농갱이(Leiocassis ussuriensis) 274개체의 척추골을 이용하여 연령과 성장을 분석하였다. 대농갱이의 연령은 척추골에 형성된 윤문을 통해 결정하였다. 본 연구 결과 척추골는 연령 측정에 적합한 자료로 판단되었다. 척추골에는 매년 4월에 1회 성장륜이 형성되었으며, 산란기는 5월부터 7월, 초륜은 약 10개월(0.83년)이 지난 시점에 형성되었다. 척추골을 기준으로 분석한 결과, 암컷과 수컷 간의 전장의 성장에는 유의한 차이가 없었다(p>0.05). 척추골을 기준으로 전장(TL)에 대해 추정된 von Bertalanffy 성장식은 다음과 같다:          .

The global cod market is supposed to have weak structure with a high dependence on the supply of Russia, the United States, Norway, and China. The COVID-19 pandemic has significantly disrupted the cod supply chain for the worse. Fish processing facilities in China stopped their operation, and cod demand declined due to shrinking consumption in Europe. The position of South Korea as an intermediary trade country between Russia and China strengthened due to the U.S.-China trade war and the Atlantic cod decrease in 2019. However, this global cod supply chain collapse has caused South Korea to export accumulated cod to Indonesia and Vietnam at a bargain price, showing that South Korea was unable to cope with this supply chain crisis. The primary purpose of this study is to investigate changes in the global cod supply chain and their impacts on the intermediary trade of South Korea caused by the COVID-19 pandemic. It also aims to provide implications by analyzing advanced cases in Denmark. As the cod supply chain crisis countermeasures, this study suggests that South Korea develop high value-added marine products, gain competitive advantages by solidifying the value chains of related countries, and activate export by discovering alternative markets in terms of the supply chain of the cod industry.

Ammonium dinitramide (AND) is one of the most promising oxidizers in propellants without chlorinated pollution to the atmosphere in these days. Potassium sulfamate (PS) is a key substance in ADN synthesis as forming nitrates such as -N(NO2)2. In this paper, potassium sulfamate as a starting material for ADN synthesis was prepared in a lab scale through crystallization with ethanol solvent, and observed the effects on the yield and purity of KDN. The prepared potassium sulfamates were analyzed using FE-SEM, XRD, BET and TGA-DSC. The lab-made PS, which was ground to 20μm showed more beneficial than a commercial product achieving high yield and purity of the synthesized KDN. It would be associated closely with crystallinity, porosity and pore size of prepared PS.