• 한국인쇄학회지
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• 제28권1호
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• pp.65-75
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• 2010

Environmentally friendly, stencil and screen printing for cost-effective for maskless. In this study, UV -LED light source for the dispersion characteristics and high competence photoresist coating was prepared. Wavelength of 365nm UV-LED exposure device using the maskless lithography, 1.7kgf/$cm^2$ $2600mmH_2O$ the injection pressure and the suction pressure by using a dry photoconductor symptoms were dry emulsion on the market as a result, curing properties and adhesion, hardness, solvent resistance and excellent reproduction of fine patterns and ecological stencil technology was available and could be confirmed as a possibility.

• Journal of electromagnetic engineering and science
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• 제6권2호
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• pp.130-134
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• 2006

This paper presents the reduction characteristics of penetrated electromagnetic fields through a narrow slot in a planar conducting screen of infinite extent. When a plane wave is excited to the narrow slot, the aperture electric field is controlled by the parallel wire or parallel plate connected on the slot. The magnitude of penetrated electromagnetic fields through a narrow slot is controlled by electric field distributions on the slot. An integral equation for the aperture electric field on narrow slots is derived and solved by applying Galerkin's method of moments. The results show that the magnitude of the penetrated electromagnetic field can be effectively reduced by installing the parallel wire or parallel plate on the slot.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 춘계학술대회논문집
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• pp.66-68
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• 2005

This paper presents the reduction characteristics of penetrated electromagnetic fields through a narrow slot aperture in a planar conducting screen of infinite extent. When a plane wave is excited to the narrow slot, the aperture electric field is controlled by the parallel plate connected on the slot. The magnitude of penetrated electromagnetic fields through a narrow slot is controlled by electric field distributions on the slot aperture. An integral equation for the aperture electric field on narrow slots is derived and solved by applying Galerkin's method of moments. The results show that the magnitude of the penetrated electromagnetic field can be effectively reduced by installing the parallel plate on the slot aperture.

• Journal of electromagnetic engineering and science
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• 제9권2호
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• pp.105-109
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• 2009

The problem of electromagnetic coupling between a slit fed by a flanged parallel-plate waveguide(PPW) and a slit in an infinite nearby conducting screen parallel to the flanged ground conductor is studied as a simplified problem for a near-field scanning microscopy(NSM). The method of moments isused to solve the coupled integral equations for the electric field distributions over the slits. The performance of the proposed apparatus as an NSM is tested by examining the effects of some geometrical parameters on the equivalent slit admittance and coupled powers through the slits.

• 한국인쇄학회지
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• 제31권1호
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• pp.1-14
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• 2013

Screen printing is a printing method with flexible plate surface characteristics. In addition, since the appearance of electronics industry the screen printing has been demanding high quality and definition. However, Screen printing is a method for taking ink through mesh opening because screen mesh tends to restrict quality of screen printing. In particular, the biggest problem compared with other printing type is halftone reproduction characteristics. Halftone reproduction characteristics for screen printing depend on screen mesh and opening. Dot losses or dot gains are observed through various types of screen mesh because thread of screen mesh interfere with the movement of the ink. Excessive dot losses or gains can affect the tonal range. Furthermore, this problem can result in other problem such as bad contrast and gray balance. Therefore, it is an important factor to use proper screen mesh for halftone screen printing. However, domestic screen printing industry relies on worker's experience in field rather than depending on objective data although standardized specifications and optimal printing conditions are required for screen printing. For this reason, it is important to stipulate standard condition for domestic screen printing industry. Therefore, it was examined to find tonal range by mesh opening in halftone prints process of screen printing used domestic paper and ink in this study. In addition, TVI(Tone Value Increase) characteristic was observed by comparing to the manuscripts and prints of the dot area ratio. Furthermore, contrast value and gray balance were confirmed for each condition of the printout. Conditions for the proper selection of screen mesh screen for the quality of the prints were also examined, compared with the international standard of screen printing, ISO 12647-5.

• 대한기계학회논문집B
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• 제25권5호
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• pp.722-730
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• 2001

The local heat transfer of an axisymmetric submerged air jet impinging on a heated flat plate is investigated experimentally with the variation of mesh-screen solidity. The screen installed in front of the nozzle exit modifies the flow structure and local heat transfer characteristics. The mean velocity and turbulence intensity profiles of streamwise velocity component are measured using a hot-wire anemometry. The temperature distribution on the heated flat surface is measured with thermocouples. The smoke-wire flow visualization technique was employed to understand the near-field flow structure qualitatively for different mesh screens. Large-scale toroidal vortices and high turbulence intensity enhance the heat transfer rate in the stagnation region. For a higher solidity, turbulence intensity become higher which increases the local heat transfer at small nozzle-to-plate spacings such as L/D<6. The local and average Nusselt numbers of impinging jet from the $\sigma$(sub)s=0.83 screen at L/D=2 are about 5.6∼7.5% and 7.1% larger than those for the case of no screen, respectively. For the nozzle-to-plate spacings larger than 6, however, the turbulence intensities for all tested screens approach to an asymptotic curve and the mean velocity along the jet centerline decreases monotonically. As the nozzle-to-plat spacing increases for high solidity screens, the heat transfer rate decreases due to the reduction in turbulence intensity and jet momentum.

• 한국인쇄학회지
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• 제19권2호
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• pp.49-57
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• 2001

This thesis attempts to study ink transition for on the polycarbonate multicalculator plate for automobile. For this study, the change of weight by screen printed ink transition on polycarbonate material by ink viscosity(be diluted ; 0%, 5%, 10%, 20%) was observed. The weight by screen printed ink is depended on amount of added solvent. We have studied change of the weight by the transition of the ink that was screen-printed on polycarbonate which is to be printed according to the viscosity of the ink (diluent: undiluted solution 5%, 10%, 15%, 20%). This shows that ink transition become activated since the amount of ink(or/and the viscosity of ink) is increased.

• 한국가구학회지
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• 제28권4호
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• pp.259-267
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• 2017

Furniture should change according to space. Therefore, it is important that the flexibility of the furniture, the functional efficiency, the economical efficiency and the convenience of the furniture of today. These characteristics are also important for seminar tables that are used temporarily by a large number of people. The seminar furniture currently in use has no shielding plate, there are two forms of table and shielding plate folding table. Therefore, in this research, furniture design and product development that can complement the shortcomings of the seminar furniture currently in use were done. Analysis of problems through overseas investigation and domestic market research, design planning and design, and prototyping. We have sought to optimize the volume by applying the characteristics of RTA furniture to develop a lightweight, lightweight, lightweight, easy to install and easy to use shielding plate, and open and closed system. Basically developed two types of shielding board seminar table basic shape and Roll Screen type, we expanded the scope of application such as each color and pattern. In order to reduce the weight, we replaced the parts such as anchor bolts and hinges and the shielding plate with Roll Screen and pursued volume optimization. As a result of this research, it is expected that the system of mechanisms such as packaging standardization and damage prevention for weight reduction and volume optimization will contribute to building competitiveness by domestic office prefabricated furniture industry's original technology.

• 대한기계학회논문집
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• 제14권2호
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• pp.367-375
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• 1990

A data structure representing 3-D objects was designed for the personal computer. It is very simple to be used in the personal computers which have small memory and low speed. A homogeneous transformation for developing 3-D objects was derived. Each developing procedure consists of five transformations : one translational-three rotational-one translational. Developing a solid is a creative work. So the results of developing vary with the order of surfaces to be developed. One method to reduce the length of seam was considered. The programs used in this study were written in Pascal and Assembly and a modeller that generates 3-D primitives was included. This program is an interactive dual-screen system. While all the menus in Korean are displayed at the monochrome monitor, the development figures with projective views are drawn at the color monitor. The program has wide applications for plate works.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.65-68
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• 1999

A well oriented Bi2212 superconductor thick films were fabricated by screen printing with a Cu-free Bi-Sr-Ca-O mixture powder on a copper plate and heat-treating at 820-88$0^{\circ}C$ for several minute in air. During the heat-treatment, the printing layer partially melted by reaction between the Cu-free precursor and CuO of the oxidizing copper plate. In the partial melting state, it is believed that the solid phase is Bi-free phase and Cu-rich phase and the composition of the liquid is around Bi : Sr : Ca : Cu = 2 : 2 : 0 : 1. Following the partial melting, the Bi2212 superconducting phase is formed at Bi-free phase/liquid interface by nucleation and grows. With decreasing the Bi composition in the precursor powder, the critical temperature(T$_{c}$) of the fabricated Bi2212 thick film increased to about 79 K.K.