• Title/Summary/Keyword: Sealing

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The Reliability Test of Sealing Glass Frit in AC PDP

  • Jeon, Young-Hwan;Hwang, Jong-Hee;Lim, Tae-Young;Kim, Hyung-Sun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1538-1541
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    • 2005
  • For reliability evaluation of AC-PDP, one of the most important factor is sealing property. In this paper, the reliability evaluation test method of the commercialized sealing glass frit in AC-PDP was studied. 6 inch AC-PDP panels were tested for evaluation of sealing glass frit by vibration shock test, thermal shock test, non -destructive X-ray inspection, residual stress inspection and residual gas detection. These test methods are proposed as a standard for testing the reliability of sealing glass frit. The main failure mode of sealing glass frit in AC-PDP seems to be the crack propagation from thermal cycling rather than mechanical factor.

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Development of an Optimal Trajectory Planning Algorithm for an Automated Pavement Crack Sealer

  • Yoo, Hyun-Seok;Kim, Young-Suk
    • Journal of Construction Engineering and Project Management
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    • v.2 no.1
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    • pp.35-44
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    • 2012
  • In the last two decades, several tele-operated and machine-vision-assisted systems have been developed in the construction and maintenance area, such as pavement crack sealing, sewer pipe rehabilitation, and excavation. In developing such tele-operated and machine-vision-assisted systems, trajectory plans are very important tasks for the optimal motions of robots whether their environments are structured or unstructured. This paper presents an optimal trajectory planning algorithm used for a machine-vision-assisted automatic pavement crack sealing system. In this paper, the performance of the proposed optimal trajectory planning algorithm is compared with the greedy trajectory plans, which are used in the previously developed pavement crack sealing systems. The comparison is based on the computational cost vs. the overall gains in crack sealing efficiency. Finally, it is concluded that the proposed algorithm plays an important role in the productivity improvement of the developed automatic pavement crack sealing system.

Numerical Study of Behaviour Characteristics of Mechanical Seals with Inclined Friction Faces (경사진 마찰접촉면을 갖는 기계경사면시일의 거동특성에 관한 수치적 연구)

  • Kim Chung Kyun
    • Tribology and Lubricants
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    • v.20 no.6
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    • pp.314-321
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    • 2004
  • Thermal distortion of non-contacting mechanical seals with inclined rubbing surfaces is affected by friction heat between seal ring and seal seat. The circulation fluid along the inclined rubbing surfaces maintains cooling friction heat and lubrication between the sealing surfaces of mechanical seal with an inclined surface. Mechanical seals with inclined sealing surfaces may be useful for reducing the frictional heating and power loss because of the introduction of cooling fluids to the sealing gap between seal ring and seal seat. From the FEM computed result shows that the thermal behavior and von Mises stress of sealing faces with an inclined angle 60 are much reduced in comparison of the conventional mechanical face seal with rectangular sealing surfaces.

The Low Temperature Laser Treatment of Sealing Glass Substrate for ECL (ECL용 유리기판의 레이저 저온 실링처리)

  • Choi, Hye-Su;Park, Cha-Soo;Gwak, Dong-Joo;Sung, Youl-Moon
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.1134-1135
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    • 2015
  • In this paper, we reported fabrication of sealing the glass substrate using laser treatment at low temperature for electrochemical luminescence (ECL) cell. The laser treatment at temperature is using laser diode. The glass substrate sealing by laser treatment tested at 1-5 W, 1-5 mm/s for builted and tested. The sealing laser treatment method will allow associate coordination between the two glass substrate was enclosed. The effect of laser treatment to sealing the glass substrate was found to have cracks and air gap at best thickness of about $845-780{\mu}m$ for condition 5 W, 1-5 mm/s. The surface of sealing was roughness which was not influent to electrodes So, it is more effective viscosity between two glasses substrate.

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A Basic Study on Storage of Leaf, Stem and Root in Angelica acutiloba Kitag

  • Choi Seong-Kyu
    • Korean Journal of Plant Resources
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    • v.19 no.3
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    • pp.436-439
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    • 2006
  • This study was carried out to obtain basic information for optimum storage method of leaf, stem and root of Angelica acutiloba Radix, which is being utilized as major cultivated herbal medicine materials, root of Angelica acutiloba was stored for 3 months in different packing materials and sealing methods, such as punched packing, sealing and vacuum packing. The results are summarized as follows. The loss in weight as influenced by packing materials and sealing degree was the lowest at vacuum packing and complete sealing condition with transparent polyethylene film. The ratio of root rot during the storage period was not significantly different between polyethylene films, but it was significantly different between sealing conditions. Therefore, vacuum packing and complete sealing with polyethylene film are desirable storage condition for Angelica acutiloba Radix.

Mechanical Properties of Breathable Waterproof Fabrics with Seaming and Sealing Processes

  • Jeong Won Young;An Seung Kook
    • Fibers and Polymers
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    • v.5 no.4
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    • pp.316-320
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    • 2004
  • Waterproof fabrics are seamed and sealed by waterproof sealing tape to prevent water from penetrating through the stitch holes. As this process may change the mechanical properties of breathable waterproof fabric related to its deformation with human body, the changes in mechanical properties were investigated. In both of parallel and perpendicular directions, tensile characteristics were remarkably changed with seaming and sealing processes. The increase of LT and WT means that the clothing sealed by waterproofing tape may produce somewhat discomfort feeling. On the other hand, the bridge of the sewing thread seemed to be reinforced by waterproofing tape. Shear characteristics such as G, 2HG, and 2HG5 gradually increased with seaming and sealing processes in parallel direction. However, they decreased with sealing process in perpendicular direction because the seam line would work as an axis located at the center of the testing range.

Electrical and Optical Characteristics of Plasma Display Panel Fabricated by Vacuum In-line Sealing (진공 인라인 실장에 의해 제작된 플라즈마 디스플레이 패널의 전기적ㆍ광학적 특성)

  • Park, Sung-Hyun;Lee, Neung-Hun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.4
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    • pp.344-349
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    • 2005
  • The optical and electrical characteristics of plasma display panel(PDP) using the vacuum in-line sealing technology compared with the conventional sealing process in this research. This PDP consisted of MgO protecting layer by e-beam evaporation and battier rib, transparent dielectric layer, dielectric layer, and electrodes by screen printer and then sealed off on Ne-Xe(4 %) 400 Torr and 430。C. The brightness and luminous efficiency were good as the base vacuum level was higher, and it was to check the advantage of high vacuum level sealing, one of the strong points of the vacuum in-line sealing process. However, the brightness and luminous efficiency was dropped sharply because of a crack on MgO protecting layer by the difference of the expansion and contraction stress on high temperature in the vacuum states between MgO and substrate. Fortunately, the crack was prevented by MgO was deposited on higher temperature than 300。C. Finally, the PDP, was fabricated by the vacuum in-line sealing process, resulted the lower brightness than processing only the thermal annealing treatment in the vacuum chamber, but the luminous efficiency was increased by the reducing power consumption with the decreasing luminous current. The vacuum in-line sealing technology was not to need the additional thermal annealing process and could reduce the fabrication process and bring the excellent optical and electrical properties without the crack of MgO protecting layer than the conventional sealing process.

Analysis of Electrochemical Corrosion Resistance of Inconel 625 Thermal Spray Coated Fin Tube of Economizer (Inconel 625 용사코팅된 절탄기 핀튜브의 전기화학적 내식성 분석)

  • Park, Il-Cho;Han, Min-Su
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.1
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    • pp.187-192
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    • 2021
  • In this study, Inconel 625 was used as a thermal spray material to prevent dew point corrosion damage to the economizer tube, and sealing treatment was performed after applying the arc thermal spray coating technology. Various electrochemical experiments were conducted in the 0.5 wt% sulfuric acid solution to analyze the corrosion resistance of the thermal spray coating (TSC) layer. After the anodic polarization experiment, the degree of corrosion damage was determined through a scanning electron microscope and EDS component analysis. When measuring the open circuit potential, the effect of the sealing treatment was confirmed through stable potential formation of the TSC+sealing treatment (TSC+Sealing). As a result of the anodic polarization experiment, the passivation region was confirmed in TSC and TSC+Sealing, and corrosion resistance was improved as no corrosion damage was observed. In addition, the corrosion resistance of TSC+Sealing was the best when analyzing the corrosion potential and corrosion current density calculated by Tafel analysis.

An Experimental Study on Sealing Performance Improvement for Oil Mist Luibrication Environment (오일 미스트 윤활환경의 밀봉성능향상을 위한 실험적 연구)

  • 나병철;전경진;한동철
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.4
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    • pp.76-82
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    • 1998
  • Sealing an oil-air mixture plays important roles to have an enhanced lubrication for high speed spindle. Current work is emphasized on the investigation of the air jet effect on the protective collar type labyrinth seal. To improve the sealing capability of conventional labyrinth seal, air jet is injected against through the leakage flow. It has a combined geometry of a protective collar type and an air jet type. In this study, both of a numerical analysis by CFD(Computational Fluid Dynamics) and experimental measurements are carried out to verify sealing improvement. Both of the turbulence and the compressible flow model are introduced in CFD analysis. The sealing effect of the leakage clearance and the air jet magnitude are studied for various parameter in the experiment. The results of pressure drop in the experiment match reasonably to those of the simulation by introducing a flow coefficient. Effects of sealing improvement are explained as decreasing of effective leakage clearance by air jetting. Thus, sealing effect is improved by amount of air jetting even though clearance becomes larger.

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Direct Sealing Glass-Ceramics to Metal (직접 결합방법에 의한 Glass-Ceramics과 금속의 접합)

  • Kim, Hwan;Lee, Ki-Kang
    • Journal of the Korean Ceramic Society
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    • v.18 no.2
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    • pp.99-104
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    • 1981
  • Glass-ceramics possessed a number of characteristics which suggested their suggested their use for sealing to metals. The choice of particular glass-ceramics compositions for this application is governed by various factors, including workability of the glasses, thermal expansion characteristics and the matching of these to appropriate metals. Other properties, such as mechanical strength, determined the performance of glass-ceramics to metal seals. The purpose of the present study was to investigate direct sealing behaviour of copper to $Li_2O-ZnO-SiO_2$ system glass-ceramics. The design of the seal was a concentric seal which might contribute to the strong bond formation by providing compressive stress during thermal excursions. Tensile strengths of sealing layers were measured by Instron test machine. The layers were examined by electron probe microanalyzer. Crsystallization rate was increased with the amount of ZnO or $Li_2O$, and ZnO increased the sealing strength, but $Li_2O$ lowered it. Sealing mechanism was due to the formation of metal oxides, which acted as binder between copper and glass-ceramics. The nickle-plated copper seal with 10% $Li_2O$ and 30% ZnO was the most strong seal, and its sealing strength was more than 56kg/$\textrm{cm}^2$.

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