• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2004.05a
• /
• pp.257-262
• /
• 2004

A series of preliminary model tests are performed to find out the wave attenuating effect of the pneumatic breakwater of environment friendly type, which is a bubble screen generated by releasing compressed air from a submerged multiple parallel manifold Rising bubbles induce vertical current, which produces horizontal currents flowing away from the bubble-screen area in both directions. Near bottom, the corresponding currents flow toward the bubble screen, thus completing the circulation pattern. The surface current moving against the direction of wave propagation causes some attenuation of the waves. It becomes more effective as the relative depth (d/ L) increases (short-period waves in deep water). With the same air-discharge, the multiple parallel manifold can be more effective for the attenuation of longer waves through optimum arrangement of manifold number. installation depth, manifold gap, etc. The pneumatic breakwater will give a wide utilization as a device for protecting harbor facilities and as a simple, mobile breakwater.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.19 no.6
• /
• pp.36-42
• /
• 2020

Nowadays, the touch screen panel (TSP) cover glass for mobile smart devices is being developed with a curved glass shape due to different design requirements. Because the sizes of mobile smart devices continue to increase, there has also been a great increase in the demand for large-area curved glass greater than 20 inches. In this study, heat and fluid flow analysis using CFD was performed to optimize the heating surface temperature distribution of the large curved glass formation system. Five cooling water flow paths in the cooling block were designed and analyzed for each case. A function that can quantitatively calculate the temperature uniformity of the heating surface was proposed and these values were obtained for the five models. The temperature distributions of the heating surface and the energy consumption of the heating system were also compared and comprehensively analyzed. Based on the analysis results of the five different cooling channel path models, the optimal path design could be presented.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.13 no.1
• /
• pp.13-24
• /
• 1995

The color filter os made in four methods ; dyeing, printing electrodisposition and pigment dispersed method. Among technologies for color filter manufacture, pigment-dispersed and hybrid method are dominant over all others in commercial manufacture of large scale, fine resolution color filter for liquid crystal display. In this paper to investigate the possibility of the color filter manufacture for LCD by screen printing method, we synthesyzed PVA/sbQ screen emulation for high resolution, estimated image of printed fine pattern and manufactured color filter by screen printing. Results of the study are as follow and found the screen printing method os useful and valid from it. 1. Fine pattern is formed due to photocyclodomerization of -C=C- bond at 342nm, on the other hand unexposured parts are removed in water. 2. sharpness and resolution of fine pattern is improved at mesh streching angle 22.5 and 45 than 0 degree. It is expected due to resistance between inks and mesh streching angles. 3. Spectral characteristics of sample inks were R(640nm), G(535nm), B(470nm), transmittance were R(92%), G(79%), B(70%) and chromaticity coordinate values were R(0.62,0.33), G(0.32,0.59), B(0.14,0.17)

• ETRI Journal
• /
• v.44 no.4
• /
• pp.686-694
• /
• 2022

Fog screens offer a great advantage to be used as scattering screens in three-dimensional displays. In the absence of a fixed rigid form, fog screens work as screens without any physical obstruction. The density of water droplets can be regulated to adjust the screen's transparency and scattering level. This study proposes a method for crosstalk reduction between adjacent viewing windows by decreasing the divergence of view of the projector, with concentration lenses. By applying the Scheimpflug principle, we also reduce the keystone effect, which occurs when the fog screen is slanted with respect to the optical axis. In this study, we have realized a tabletop multiview fog display without any structures on the table and established that the proposed method is feasible for decreasing crosstalk effectively.

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

• The Journal of the Korea Contents Association
• /
• v.16 no.3
• /
• pp.116-124
• /
• 2016

In this paper, we propose digital exhibition contents for the aquarium, especially 'Gyeongpo Lagoon Ecological Museum'. We try to plan appropriate media contents that can be mixed with the aquarium storytelling. The aquarium must have special spaces that are not related with an exhibition directly but are necessary for survival of fishes such as a water circulation room. We design the special spaces using media contents and let visitors feel that the whole aquarium is in the ocean. First of all, we investigate the aquarium currently under construction. And then, we propose the appreciate media platforms and plan individual content. We suggest 3 types of media platforms, 3D water projection, interactive games utilizing Kinect, and a fog screen. Moreover, we produce 2D drawing concepts, 3D modeling images, and virtual exhibitions in virtual reality for the representation of the location in which those platforms are installed and the media contents we plan. The pre-visualization is helpful for the media platform construction and is used as a rough sketch to producing an animation shown in the exhibition.

• Nuclear Engineering and Technology
• /
• v.55 no.7
• /
• pp.2621-2627
• /
• 2023

In Experimental Advanced Superconducting Tokamak (EAST) experiments, to achieve long pulse and high-power ICRH system operation, a new kind of ICRH antenna has been designed. One of the most critical factors in limiting the operation of long pulse and high power is the intense heat load in the front face of the ICRH antenna, especially the Faraday Screen (FS). Therefore, the cooling channels of FS need to be designed. According to thermal-hydraulic analysis, the FS tubes are divided into several groups to achieve more excellent water cooling capability. The number of series and parallel tubes in one group is chosen as six. This antenna went into service in the spring of 2021, and it is delightful that the temperature distribution of the FS tube is below 400 ℃ in 14.5 s and 1.8 MW ICRH system operation. However, the active water-cooling design was not carried out on the upper and lower plates of FS, which led to severe ablations on that region under long pulse and high power operation, and the temperature is up to 800. Therefore, the upper and lower side plates of the FS were designed with water cooling based on thermal-hydraulic analysis. During the 2022 winter experiments, the temperature of ICRH antenna FS was lower than 400 in the pulse of 200s and the power of 1 MW operation.

• Journal of Adhesion and Interface
• /
• v.7 no.3
• /
• pp.16-25
• /
• 2006

Water vapour permeable and water resistant film was laminated to made footwear woven fabric and non-woven fabrics by screen type with thermosetting reactive hot melt adhesive. Optimum conditions of each process were investigated, and the properties of film laminated fabric with optimum conditions are evaluated. The results are as follows. Thermosetting reactive polyurethane hot melt is retain proper heat resistance differently thermoplastic hot melt. Optimum melting adhesive process conditions are as follows ; drum temperature $95^{\circ}C$, hose temperature $97^{\circ}C$, feeding pipe temperature $100^{\circ}C$, screen temperature $105^{\circ}C$, pressure of opposite roller $1kgf/cm^2$, pressure of laminating roller $3kgf/cm^2$, finishing speed 15 m/min, melting temperature $120^{\circ}C$, cooling time 20 s, pressing temperature $130^{\circ}C$, pressing time 30 s. As the thickness of film was increased, the water vapour permeability was decreased but water resistance was increased, and the effect of film is dominant over all the others in the air permeability.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.31 no.2
• /
• pp.39-44
• /
• 2023

This study was conducted to analyze problems related to non-water-soluble sanitary products during the treatment of water regeneration centers in E.T.F. and S.T.F. at a time when the demand and supply of non-water-soluble sanitary products are increasing. As a result, the improvement plan of the W.R.C. should focus on pretreatment facilities. When replacing facilities in the future, various dust removers suitable for the facility's reality will be installed in the pretreatment of S.T.F., and it is proposed to link a bar-racks screen with a comprehensive treatment device or install a comprehensive treatment device for impurities alone in the pretreatment of E.T.F.. In addition, a microscreen screen must be installed on the front end of the excretory treatment unit. to separate non-water-soluble materials, and it is necessary to secure a maintenance space for the excretory treatment unit.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.4
• /
• pp.256-262
• /
• 2009

The use of hydrodynamic separator is becoming increasingly popular for suspended solids reduction in urban storm runoff. This study is a laboratory investigation of the use of Vortex Screen to reduce the solids concentration of synthesized storm runoff. The synthesized storm runoff was made with water and addition of particles; manhole sediment, road sediment, fly ash, and ployvinyl chloride powder. Vortex Screen was made of acryl resin with 250 mm of diameter and height of 700 mm. To determine the removal efficiency for various influent concentrations of suspended solids (SS) and chemical oxygen demand (COD), tests were performed with different operational conditions. The samples were taken simultaneously at the influent storage tank and effluent tank, and measured SS and COD concentrations. The ranges of surface loading rate were 110 to 1,550 $m^3/m^2$/day, and influent SS concentrations were varied from 141 to 1,986 mg/L. This paper was intended to evaluate the effect of inlet baffle and the ratio of underflow to overflow ($Q_U/Q_O$) on particle separation efficiency for various particle size using Vortex Screen. It was found that when increase of $Q_U/Q_O$ from 10% to 20%, SS removal efficiency was increased about 6%. The range of SS and COD removal efficiencies of road sediment particle size 125<$d_p$<300 ${\mu}m$ were 68.0~81.0%, 53.1~71.9%, respectively. Results showed that SS removal efficiency with inlet baffle improved by about 10~20% compared without inlet baffle.