• Journal of Industrial Technology
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• v.26 no.B
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• pp.63-71
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• 2006

The concerned object of the construction industry is environment. It is one of the main purposes of today's construction that human can live reasonably in nature. This study is about the fish-road connecting hydraulic structure in the river with nature. Chapter 2, starting with the general investigation about fish-road and helps comprehension for relatively general fish-road such as necessity, establishment purpose, history, study example, relating domestic law, design condition, consideration and form of fish-road. Chapter 3, containing the present condition of fish-road facilities in Gangwon-Do and thoughts of the problems and general countermeasures of existing fish-road. Chapter 4, Having Examined compatibility by amount of flowing water through hydraulic model test in the Ice harbor I-type model. chapter 5, Analyzation and arrangement to efficient establishment plan of fish-road and the result of the hydraulic model experiment to be beaconed a little in forward fish-road study. In the hydraulic model test result, when we suppose establishment of 1~3 in slope of 1/20, could know that applicable drought flow of the river is $0.06{\sim}3.0m^3/sec$ in case of Ice harbor I-type which transforming Ice harbor that was invented as studying project of the Ministry of Environment.

• Korean Journal of Human Ecology
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• v.16 no.5
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• pp.1031-1040
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• 2007

The purpose of this study was to assess the causal relationships of attitude toward fish eating, health involvement, convenience, fish consumption and age. A total of 235 questionnaires were completed. Structural equation model was used to assess the causal relationships among constructs. Results of the study demonstrated that the structural equation analysis result for the data also indicated excellent model fit. The influences of age on health involvement and convenience were statistically significant. The influences of health involvement on attitude toward fish eating and fish consumption behavior were statistically significant. The influence of convenience on fish consumption behavior were statistically significant. Moreover, the age had a significant indirect effect on attitude toward fish eating through health involvement. The age also had a significant indirect effect on fish consumption behavior through convenience.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.4
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• pp.419-427
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• 2011

Simulation technique for the fish behavior was applied to estimate fish school movement in the cage net. Individual-based fish behavior model (Huth and Wessel, 1991) was evaluated in a free area to understand the characteristics for the model, and the movement in the cage net was simulated by defining the fish reaction against the displacement of cage net. As a result, the distance to the net was not considerably changed and the space among fishes in cage net was slightly decreased by reducing the net space. Swimming area was, however, significantly affected by changing the net space and the relationship between swimming area and net displacement was theoretically estimated as y=-0.21x+1.02 ($R^2$=0.96). these results leads the conclusion that individual-based model was appropriated to describe the fish school reaction in the cage net and be able to use for evaluating the influence on cultured fish.

• Fisheries and Aquatic Sciences
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• v.10 no.3
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• pp.159-169
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• 2007

The complex 2-dimensional movements of fish during an annual migration circuit were generated and simulated by a chaotic model of fish movement, which was expanded from a small-scale movement model. Fish migration was modeled as a neural network including stimuli, central decision-making, and output responses as variables. The input stimuli included physical stimuli (temperature, salinity, turbidity, flow), biotic factors (prey, predators, life cycle) and landmarks or navigational aids (sun, moon, weather), values of which were all normalized as ratios. By varying the amplitude and period coefficients of the klinokinesis index using chaotic equations, model results (i.e., spatial orientation patterns of migration through time) were represented as fish feeding, spawning, overwintering, and sheltering. Simulations using this model generated 2-dimesional annual movements of sea bream migration in the southern and western seas of the Korean Peninsula. This model of object-oriented and large-scale fish migration produced complicated and sensitive migratory movements by varying both the klinokinesis coefficients (e.g., the amplitude and period of the physiological month) and the angular variables within chaotic equations.

• Fisheries and Aquatic Sciences
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• v.7 no.3
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• pp.163-170
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• 2004

A fishing simulator for towed fishing gear was investigated in order to mimic the fish behavior in capture process and investigate fishing selectivity. A fish behavior model using a psycho-hydraulic wheel activated by stimuli is established to introduce Lorenz chaos equations and a neural network system and to generate the components of realistic fish capture processes. The fish positions within the specified gear geometry are calculated from normalized intensities of the stimuli of the fishing gear components or neighboring fish and then these are related to the sensitivities and the abilities of the fish. This study is applied to four different towed gears i.e. a bottom trawl, a midwater trawl, a two-boat seine, and an anchovy boat seine and for 17 fish species as mainly caught. The Alpha cluster computer system and Fortran MPI (Message-Passing Interface) parallel programming were used for rapid calculation and mass data processing in this chaotic behavior model. The results of the simulation can be represented as animation of fish movements in relation to fishing gear using Open-GL and C graphic programming and catch data as well as selectivity analysis. The results of this simulator mimicked closely the field studies of the same gears and can therefore be used in further study of fishing gear design, predicting selectivity and indoor training systems.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.167-176
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• 2020

The automated fish feed system currently used in Korea supplies a certain amounts of feed to water tanks at a certain time. This automated system can reduce the labor cost of managing aqua farms, but it is very difficult to control intelligently and appropriately the amount of expensive feed that is critical to aqua farm productivity. In this paper, we propose the FIIFF Inference Model( Fuzzy Inference-based Intelligent Fish Feeding Model) that can solves the problems of these existing automatic fish feeding devices and maximizes the efficiency of feed supply while properly maintaining the growth rate of fish in aqua farms. The proposed FIIFF inference model has the advantage of being able to control feed amounts appropriately since it computes the amount of feed using the current water environments and fish activity state of the aqua farms. The result of the feed amount yield experiment with the proposed FIIFF Inference Model represents the effect of saving 14.8% over the eight months of actual feed amount in the aqua farm.

• Fisheries and Aquatic Sciences
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• v.11 no.1
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• pp.61-69
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• 2008

Using empirical data of fish performance and physiological limits as well as physical stimuli and environmental data, a cod-end selectivity model based on a chaotic behavior model using the psycho-hydraulic wheel and neural-network approach was established to predict fish escape or herding responses in trawl and cod-end designs. Fish responses in the cod-end were categorized as escape or herding reactions based on their relative positions and reactions to the net wall. Fish movements were regulated by three factors: escape time, a visual looming effect, and an index of body girth-mesh size. The model was applied to haddock in a North Sea bottom trawl including frequencies of movement components, swimming speed, angular velocity, distance to net wall, and the caught-fish ratio; simulation results were similar to field observations. The ratio of retained fish in the cod-end was limited to 37-95% by optomotor coefficient values of 0.3-1.0 and to 13-67% by looming coefficient values of 0.1-1.0. The selectivity curves generated by this model were sensitive to changes in mesh size, towing speed, mesh type, and mesh shape.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.2
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• pp.233-243
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• 2015

Controlled broadband acoustic scattering laboratory experiments were conducted using a linear chirp signal (95-220 kHz), and x-ray images of live and model fish with an artificial swim bladder were analyzed to investigate the changes in orientation and frequency dependence of target strength (TS) due to morphological differences in fish swim bladders. The broadband echoes from live and model fish were measured over an orientation angle range of ${\pm}45^{\circ}$ in the dorsal plane and in approximately $1^{\circ}$ increments. The location of nulls in the simulated echo response of the SINC [sinc function] model was overlaid on the TS map, showing the orientation and frequency dependence of fish TS, and they matched very well. It was possible to infer the equivalent fish scattering size (or swim bladder) using the null spacing in the experimentally obtained broadband TS map. Good agreement was observed for inferring the equivalent scattering size between the SINC model and the broadband echoes measured for the three fish species (black scraper Thamnaconus modestus; goldeye rockfish Sebastes thompsoni; and whitesaddled reef fish Chromis notatus). Some results of this inference are discussed.

• Ocean and Polar Research
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• v.41 no.1
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• pp.35-46
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• 2019

The purpose of this study is to identify factors influencing fish production of shallow-sea aquaculture in South Korea. This study employed the two-way fixed effect and random effect models based on the panel models and also the difference between GMM and system GMM models based on the dynamic panel models using the amount of fish farming production, the number of stocked fry, the number of cultured fish, the amount of inputted feed, the farming area, the number of workers, and the sales price data from 2010 to 2017. First, the two-way fixed effect model of the panel models was selected by panel characteristics, time characteristics and Hausman tests and also the model was statistically significant. As a result of the two-way fixed effect model, the number of stocked fry, the amount of inputted feed, and the number of workers were identified as factors that increase the fish production of shallow-sea aquaculture. However, the number of cultured fish and the sales price were analyzed as factors that reduce the fish production of shallow-sea aquaculture. Second, the system GMM model of the dynamic panel models was selected by Hansen test and Arellano-Bond test in order to identify whether or not the over-discrimination condition is appropriate. Based on the system GMM model, the number of stocked fry, the amount of inputted feed, the number of workers in this year and 1 year ago, the number of cultured fish 2 years ago, and the sale price 3 years ago were analyzed as factors that increase the fish production of shallow-sea aquaculture. However, the amount of fish farming production 1, 2, 3 years ago, the farming area in this year, and the number of cultured fish in this year and 1 year ago were identified as factors that reduce the fish production of shallow-sea aquaculture. In conclusion, this study suggests that it is desirable to control the amount of stocked fry rather than to expand the farming area for fish farming in shallow-sea aquaculture, so as to keep the sale price at a certain level by maintaining the appropriate amount of fish production.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.304-311
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• 2007

The purpose of this study was to measure the causal relationships among fish consumption behavior, attitude towards fish eating, health involvement, perceived convenience, and age. A total of 235 questionnaires were completed. A structural equation model was used to measure the causal effects of the constructs. The results of the study demonstrated that the structural analysis results were an excellent model fit for the data. The influence of age on attitude towards fish eating, health involvement, and perceived convenience was statistically significant. As expected, attitude towards fish eating, health involvement, and perceived convenience had significant effects on fish consumption behavior. Moreover, age had a significant indirect effect on fish consumption behavior through health involvement. Age also had a significant indirect effect on fish consumption behavior through perceived convenience. By developing and testing conceptual models that integrate the relationships among age, psychological variables, and fish consumption behavior, this study may offer a deeper understanding of the complex relationships among the variables. A greater understanding of these complex relationships can improve the managerial diagnoses of problems and the opportunities for different marketing strategies, including product development and marketing communications.