Fish cage systems are influenced by various oceanic conditions, and the movements and deformation of the system by the external forces can affect the safety of the system itself, as well as the species of fish being c...Fish cage systems are influenced by various oceanic conditions, and the movements and deformation of the system by the external forces can affect the safety of the system itself, as well as the species of fish being cultivated. Structural durability of the system against environmental factors has been major concern for the marine aquaculture system. In this research, a mathematical model and a simulation method were presented for analyzing the performance of the large-scale fish cage system influenced by current and waves. The cage system consisted of netting, mooring ropes, floats, sinkers and floating collar. All the elements were modeled by use of the mass-spring model. The structures were divided into finite elements and mass points were placed at the mid-point of each element, and mass points were connected by springs without mass. Each mass point was applied to external and internal forces, and total force was calculated in every integration step. The computation method was applied to the dynamic simulation of the actual fish cage systems rigged with synthetic fiber and copper wire simultaneously influenced by current and waves. Here, we also tried to find a relevant ratio between buoyancy and sinking force of the fish cages. The simulation results provide improved understanding of the behavior of the structure and valuable information concerning optimum ratio of the buoyancy to sinking force according to current speeds.展开更多
Spring Viraemia of Carp (SVC), also known as catfish infectious ascites, is an acute, hemorrhagic infectious septicaemia. The disease can harm salmon, catfish, Carassius auratus, Hypophthalmichthys molitrix, Aristicht...Spring Viraemia of Carp (SVC), also known as catfish infectious ascites, is an acute, hemorrhagic infectious septicaemia. The disease can harm salmon, catfish, Carassius auratus, Hypophthalmichthys molitrix, Aristichthys nobilis, etc., and is popular in both Europe and Asia. SVC is the first type of quarantine target for fish port quarantine. The World Organization for Animal Health (OIE) lists SVC as a disease that needs to be declared, and China’s Ministry of Agriculture defines it as a class of animal disease. In order to avoid the risk of introduction of IHN due to the introduction of fingerlings, and provide decision-making departments with scientific decision-making data, this paper conducts a systematic risk analysis of SVC from risk assessment, risk management, and risk communication.展开更多
基金supported by the National Research Foundation of Korea Grant founded by the Korean Government(MEST)(Grant No.NRF-2013R1A1A4A01011445)
文摘Fish cage systems are influenced by various oceanic conditions, and the movements and deformation of the system by the external forces can affect the safety of the system itself, as well as the species of fish being cultivated. Structural durability of the system against environmental factors has been major concern for the marine aquaculture system. In this research, a mathematical model and a simulation method were presented for analyzing the performance of the large-scale fish cage system influenced by current and waves. The cage system consisted of netting, mooring ropes, floats, sinkers and floating collar. All the elements were modeled by use of the mass-spring model. The structures were divided into finite elements and mass points were placed at the mid-point of each element, and mass points were connected by springs without mass. Each mass point was applied to external and internal forces, and total force was calculated in every integration step. The computation method was applied to the dynamic simulation of the actual fish cage systems rigged with synthetic fiber and copper wire simultaneously influenced by current and waves. Here, we also tried to find a relevant ratio between buoyancy and sinking force of the fish cages. The simulation results provide improved understanding of the behavior of the structure and valuable information concerning optimum ratio of the buoyancy to sinking force according to current speeds.
文摘Spring Viraemia of Carp (SVC), also known as catfish infectious ascites, is an acute, hemorrhagic infectious septicaemia. The disease can harm salmon, catfish, Carassius auratus, Hypophthalmichthys molitrix, Aristichthys nobilis, etc., and is popular in both Europe and Asia. SVC is the first type of quarantine target for fish port quarantine. The World Organization for Animal Health (OIE) lists SVC as a disease that needs to be declared, and China’s Ministry of Agriculture defines it as a class of animal disease. In order to avoid the risk of introduction of IHN due to the introduction of fingerlings, and provide decision-making departments with scientific decision-making data, this paper conducts a systematic risk analysis of SVC from risk assessment, risk management, and risk communication.
