• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.2
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• pp.50-56
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• 1972

This study has been carried out to observe the driving and the intercepting effects of air screen on some sea-water fishes ; Chrysophrys major, Mylio macrocephalus, Fugu pardalis. 1. By perforating fine holes on the compressed air pipes, air screen was formed in the water, and this screen was set at $45^{\circ}$, and $90^{\circ}$ against the fish passage to observe the reactions on the part of the fish. 2. Changes were given to the location of the air screen in the water to observe how the air screen drived the fish to its direction. 3. The effective distance between holes on the air piprs was determined by a series of experiments of setting up two air screens of various types in hole distance, by moving a screen to-ward the other, and of observing the distance between two screens when fish eseape through the space. The results of the above experiments observed as follows were : 1. The passage of fish was effectively intercepted by setting up the air screens at 45 degrees against the fish passage and it was also intercepted when the screen was set at 90 degrees against the passage. 2. Fish could be driven by moving the air screen toward the fish. 3. The air screen formed from the pipe above than 0.3mm in diameter was effective, but less than 0.2mm was not sufficiently effective. 4. The strength of the air pressure in the pipe should be higher than $0.087kg/cm^2$. 5. The fish holding ability to obtain effective air screen was ranged as following when the air pressure was $0.160kg/cm^2$. and the hole diameter was 0.3mm on the 12.6mm pipe, depending upon the intervals of the holes on the pipe: The shortest distance which could hold fish between two screens was 59.4cm when the holes were perforated at every 40cm; 33.5cm when at every 30cm; 28.75cm when at every 10cm: and 27.25cm when at every 5cm. Thus, no significant change was at served when the holes were perforated more densely than 30cm intervals. Therefor the hole intervals should be 30cm in designing fishing gear employing air screen.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.471-472
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• 2005

• Journal of Korea Multimedia Society
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• v.12 no.1
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• pp.130-138
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• 2009

As time spent in front of the computer screens increases, an increasing number of people are using natural landscapes or virtual aquariums as their desktop and screen saver that can provide them with mental comfort. A virtual aquarium is constructed by an animation work that creates a variety of fish that freely move in a random virtual underwater environment to analyze their movement. This paper suggests a method that constructs an immersive virtual aquarium, using fluid animation method that expresses changes of shape of fluid in real time and the Smart Fish technology which is capable of an interaction according to the diverse characteristics of virtual fish. The suggested method can be used in a virtual aquarium, aquarium screen saver, virtual fish-raising game, etc., which express diverse undersea environment.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.19 no.1
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• pp.17-24
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• 1983

The authors carried out an experiment to find the optomotor response of killifish, Orizias latipes(TEMMINCK et SCHLEGEL) and Yellowtail, Seriola quinqueradiata (TEMMINCK et SCHLEGEL) according to the colors of the netting pattern on the visual screen and the revolving velocities of the visual screen. The experimental water tank was made of 0.5 cm thick transparent acryl in the cylindrical shape (100R$\times$42H cm). The water level in the tank was maintained 30cm high from the bottom. The colors of the netting pattern (mesh size: 19.1cm, width of netting twine: 1.5cm, hanging ratio: 84%) on the three visual screens were black, red and green respectively. The revolving velocities of the visual screen were controlled by pulley, bevel gear and variable speed motor in three steps; slow (15.0cm/sec), middle (37.4cm/sec) and high (62.9cm/sec). The fish was put into the water tank before each experiment and released in it for 30 minutes in order to acclimatize itself to the tank. The visual screen was revolved for 4 minutes per each experiment, at first the fish was released for 1 minute, and then the behavior of the fish was observed for 3 minutes. In the course of clockwise and counter clockwise experiments, 10 minutes-pause was given for the rest. The behavior of the fish was observed by video system, and rounding number and swimming speed of the fish were analysed. The results obtained are as follows: (1) Optomotor response rate of Killifish and yellowtail were 95% and 94% respectively. (2) Response of the fish according to the colors of the netting pattern on the three visual screens was best in black, and second in red and third in green. (3) Response of the fish according to the revolving velocities of the visual screen was best in high speed, and second in middle speed and third in slow speed.

• Journal of Korean Society on Water Environment
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• v.30 no.5
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• pp.477-485
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• 2014

Imha Reservoir is connected to Andong Reservoir via a diversion tunnel allowing water to pass between. The diversion tunnel is equipped with screens to exclude exotic largemouth bass due to their predatory impacts on prey assemblages resulting in a degradation of species richness of local fish fauna and extinction of local fish populations in Korea. Flow pattern changes resulting from the fish screens and trash racks were investigated using a computational fluid dynamics (CFD) model. Numerical simulations showed that the decrease in the discharge capacity of the tunnel is approximately 8.6% and the headloss coefficient for fish screen at Andong intake tower was determined to be 1.5. In order not to allow the small fishes enough to pass through the wire openings enter into Imha Reservoir through tunnel, the velocity in the tunnel should be greater than 1.48 m/s which is a critical ascending velocity of the bass. This study suggests that it can keep the velocity higher enough to exclude largemouth bass when a gate opens with the condition of 1.0m difference in water stage between two reservoirs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.908-913
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• 1998

The productivity of land based seawater fish farm has been decreased because of unexpected outbreaks of diseases caused by the contaminated inlet seawater. Sometimes unfiltered/untreated outlet seawater from the land based seawater fish farm has created serious environmental problem. In the needs of treatment systems for the inlet and outlet seawater, the researchers have developed two different systems, The purpose of this study is to design and test two treatment systems, the screen filter for inlet seawater and drum filter for outlet seawater, on the basis of concept of system design and automatization. After developing two systems, an experiment has been conducted with two systems and collected data to improve design and efficiency of the system. In this study, detailed design and efficiency of the system could be improved by the programmable logic controller (PLC).

• Journal of the Korean Graphic Arts Communication Society
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• v.22 no.2
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• pp.123-138
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• 2004

The video phone tube (VPT) of monochrome CRT have utilized home door phone, fish-finder and the rear watch monitors. Phosphor screen formation is made by electrodeposition spin coating and thermal transfer methods etc. Recently, thermal transfer method was developed, as a novel method, to form the phosphor surface for mnonchrom VPT. This method have advantages of simple process, automatization, clean environment, saving raw material and saving running-cost. In this study, it was developed new phosphor of VPT, and tested about phosphor paste properties. An experimental studies of VPT as a new phosphor property and improved VPT's manufacturing process shortening and brightness. As thermal transper method is a paste processing, it is important that rheology of phosphor effects on the formation of phosphor screen. Hence this paper was studied rheology properties of phosphor paste and the formation of phosphor screen had looked most suitable condition. Experimented thermal separation properties of low calcination temperature resin and the result analyzed comparison by TGA. Also, examined calcination properties to reduce remaining binder phosphor.

• Nutrition Research and Practice
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• v.7 no.4
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• pp.330-335
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• 2013

Data are limited on the association between dietary patterns and screen time among Korean adolescents. The present study identified dietary patterns of 691 adolescents, aged 13-18 years, who had participated in the Third Korean National Health and Nutrition Examination Survey (KNHANES III) and analyzed their associations with screen time. Screen time was defined as the time spent watching TV, using a computer, or playing video games was calculated as a sum of all these times. Dietary patterns and their factor scores were derived from a food frequency questionnaire using the factor analysis method. To analyze the association between dietary patterns and screen time, we conducted multiple linear regression analysis. We also performed multiple logistic regression analysis to estimate odds ratios (OR) of excessive screen time (2 hours or longer per day) and 95% confidence intervals (CI). We identified 2 dietary patterns labeled "the Korean healthy dietary pattern" and "the Western diet and fast foods pattern". The former included mixed grains, legumes, potatoes, red meat, eggs, fish, dairy products, fruits, vegetables, seaweeds, and mushrooms, whereas the latter included noodles, bread, red meat, poultry, fast foods, snack, and soft drinks. After controlling for potential confounding factors, factor scores for the Korean healthy dietary pattern were inversely associated (P-value for trend < 0.01) and those for the Western diet and fast foods pattern were positively associated with the screen time (P-value for trend < 0.01). Adolescents in the top tertile of the scores for the Korean healthy dietary pattern had a multivariable-adjusted OR [95% CI] of 0.44 (0.25-0.75) for excessive screen time compared with those in the lowest tertile. On the basis of these findings, adolescents who have excessive screen time may need to be encouraged to consume a more healthy diet.

• YAKHAK HOEJI
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• v.44 no.5
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• pp.416-423
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• 2000

There is a growing concern that a wide variety of chemicals released into the environment can disrupt the endocrine system of fish, wildlife and humans. Endocrine disrupting chemicals (EDCs) include pesticides such as DDT lindane and atrazine, the food packaging chemicals, phthalates and bisphenol A, alkylphenol ethoxylate detergents and the chemical industry by-products, dioxins. Xenoestrogens in the environment have been argued about health risk, because of estrogen mimetic chemicals are exposed only small amounts to human. A number of in vivo and in vitro assays are now in use to assess the activity of xenoestrogens in the environment. A human breast cancer cell line (MCF-7) was used to develop in vitro screening assay for the detection of xenoestrogenic environmental pollutants. The E-SCREEN (MCF7-BUS) assay is proposed as a reliable, easy and rapid-to-perform method. To optimize and validate this method before it can be used routinely, several phenol compounds and pesticides suspected to be estrogenic were tested using I-SCREEN assay. The results showed that this method is a valuable tool for screening potential estrogen-mimicking environmental pollutants and quantitative determination of estrogeniciy.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.1
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• pp.33-41
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• 1996

In order to obtain the most favourable classification system for fishing gears, the problems in the existing systems were investigated and a new system in which the fishing method was adopted as the criterion of classification and the kinds of fishing gears were obtained by exchanging the word method into gear in the fishing methods classified newly for eliminating the problems was established. The new system to which the actual gears are arranged is as follows ; (1)Harvesting gear \circled1Plucking gears : Clamp, Tong, Wrench, etc. \circled2Sweeping gears : Push net, Coral sweep net, etc. \circled3Dredging gears : Hand dredge net, Boat dredge net, etc. (2)Sticking gears \circled1Shot sticking gears : Spear, Sharp plummet, Harpoon, etc. \circled2Pulled sticking gears : Gaff, Comb, Rake, Hook harrow, Jerking hook, etc. \circled3Left sticking gears : Rip - hook set line. (3)Angling gears \circled1Jerky angling gears (a)Single - jerky angling gears : Hand line, Pole line, etc. (b)Multiple - jerky angling gears : squid hook. \circled2Idly angling gears (a)Set angling gears : Set long line. (b)Drifted angling gears : Drift long line, Drift vertical line, etc. \circled3Dragged angling gears : Troll line. (4)Shelter gears : Eel tube, Webfoot - octopus pot, Octopus pot, etc. (5)Attracting gears : Fishing basket. (6)Cutoff gears : Wall, Screen net, Window net, etc. (7)Guiding gears \circled1Horizontally guiding gears : Triangular set net, Elliptic set net, Rectangular set net, Fish weir, etc. \circled2Vertically guiding gears : Pound net. \circled3Deeply guiding gears : Funnel net. (8)Receiving gears \circled1Jumping - fish receiving gears : Fish - receiving scoop net, Fish - receiving raft, etc. \circled2Drifting - fish receiving gears (a)Set drifting - fish receiving gears : Bamboo screen, Pillar stow net, Long stow net, etc. (b)Movable drifting - fish receiving gears : Stow net. (9)Bagging gears \circled1Drag - bagging gears (a)Bottom - drag bagging gears : Bottom otter trawl, Bottom beam trawl, Bottom pair trawl, etc. (b)Midwater - drag gagging gears : Midwater otter trawl, Midwater pair trawl, etc. (c)Surface - drag gagging gears : Anchovy drag net. \circled2Seine - bagging gears (a)Beach - seine bagging gears : Skimming scoop net, Beach seine, etc. (b)Boat - seine bagging gears : Boat seine, Danish seine, etc. \circled3Drive - bagging gears : Drive - in dustpan net, Inner drive - in net, etc. (10)Surrounding gears \circled1Incomplete surrounding gears : Lampara net, Ring net, etc. \circled2Complete surrounding gears : Purse seine, Round haul net, etc. (11)Covering gears \circled1Drop - type covering gears : Wooden cover, Lantern net, etc. \circled2Spread - type covering gears : Cast net. (12)Lifting gears \circled1Wait - lifting gears : Scoop net, Scrape net, etc. \circled2Gatherable lifting gears : Saury lift net, Anchovy lift net, etc. (13)Adherent gears \circled1Gilling gears (a)Set gilling gears : Bottom gill net, Floating gill net. (b)Drifted gilling gears : Drift gill net. (c)Encircled gilling gears : Encircled gill net. (d)Seine - gilling gears : Seining gill net. (e)Dragged gilling gears : Dragged gill net. \circled2Tangling gears (a)Set tangling gears : Double trammel net, Triple trammel net, etc. (b)Encircled tangling gears : Encircled tangle net. (c)Dragged tangling gears : Dragged tangle net. \circled3Restrainting gears (a)Drifted restrainting gears : Pocket net(Gen - type net). (b)Dragged restrainting gears : Dragged pocket net. (14)Sucking gears : Fish pumps.