• 한국세라믹학회지
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• 제31권9호
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• pp.989-994
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• 1994

This study aims at finding the closest packings of regular shape particles such as sphere, circle rod and hexagonal rod type. As the ratio of particle size to container lowered to less than 1/10, the wall effect decreased gradually. The tap density of spherical particles with almost orthorhombic arrangement was 59.5%, while those of circle rod and hexagonal rod type particles were 63.5% and 63.0% respectively. And it was decreased with increasing the aspect ratio of regular particles. The tap density of binary mixtures was larger than that corresponding to the monosized particles packing by about 15%. The tap density of ternary mixtures was larger than that of corresponding to the packing of binary mixtures by about 9%. This work employed the binary mixture of 60% coarse particles and 40% fine particles with size ratio of 1.0 to 1/10 and the ternary mixture of 60% coarse particles, 20% medium and 20% fine particles with size ratio of 1:1/10:1/400 respectively.

• 대한수학회보
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• 제48권2호
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• pp.261-275
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• 2011

We give characterizations of the differentiability points and the non-differentiability points of the Riesz-N$\'{a}$gy-Tak$\'{a}$cs(RNT) singulr function using the distribution sets in the unit interval. Using characterizations, we show that the Hausdorff dimension of the non-differentiability points of the RNT singular function is greater than 0 and the packing dimension of the infinite derivative points of the RNT singular function is less than 1. Further the RNT singular function is nowhere differentiable in the sense of topological magnitude, which leads to that the packing dimension of the non-differentiability points of the RNT singular function is 1. Finally we show that our characterizations generalize a recent result from the ($\tau$, $\tau$ - 1)-expansion associated with the RNT singular function adding a new result for a sufficient condition for the non-differentiability points.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1112-1115
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• 2007

Optical thickness method using double interferometer showed dynamic variations of both mechanical and optical thicknesses. Packing density measured a thickness ratio of before and after pressed single film. Lower swelled thickness of emitting layer in a device and densely packed film had shown better lifetime.

• 산업경영시스템학회지
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• 제25권1호
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• pp.49-55
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• 2002

For making a lead terminal(condenser, resistor etc.), it is the matter that lead wire have to be supplied smooth without twisting and curving when it is supplied to the further processing (cutting, forming, attach process) after it being forwarded. The purpose of this study is to solve the winding claims of lead wire through the structural expansion of winding equipment to which the improvement of packing equipment to forward safely and supply the lead wire and QFD method are applied. The results of this study is available to solve the technical problem caused by the installation of the existing flyer system for the prevention of twisting and can expect the quality assurance as it prevents the claim(surface fault) caused by the bumping among lead wire which are involved in the packing equipment in its moving stage.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.353-354
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• 2009

시멘트 결합재로 널리 사용되어지고 있는 고로 수쇄 슬래그 분말을 각종 분쇄기를 사용하여 입도별로 분쇄하고, 이를 혼합하여 충전률과 유동특성을 비교 분석하였으며, 입도분포 또한 비교분석 하였다. 충전률과 유동특성은 비례의 경향이 크게 나타났고, 입도분포가 넓을수록 유동특성은 높았다.

• 한국세라믹학회지
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• 제36권6호
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• pp.662-670
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• 1999

Porous alumina was fabricated from pressureless powder packing forming method using powders granulated by spray drying. It was investigated the pore size distribution of fabricated porous alumina. The results of microstructural observation showed that intraganular pore size and intragranular pore size. At 1700$^{\circ}C$ there were no intragranular pores but it showed homogeneous distribution of intergranular pore size. The bending strength and shrinkage increased as porosity decreased. In case of thermal shock resistance sudden decrease of bending strength to $\Delta$T was not shown because intergranular large pore prevented sudden crack propagation.

• 한국세라믹학회지
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• 제36권6호
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• pp.671-678
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• 1999

Porous ceramics were fabricated from pressureless powder packing forming method using mullite and cordierite powders granulate by spray drying. The bending strength and shrinkage of porous ceramics were increased and their porosity were decreased with increasing temperature. It showed homogeneous distribution of 2$\mu\textrm{m}$ intergranular pores of mullite at 1400$^{\circ}C$, 2.5$\mu\textrm{m}$ intergranular pores of cordierite at 1300$^{\circ}C$ respedtively. Above that temperature intragranular particles were sintered and sintering by intergranular necking was extremely proceeded. In the test of thermal shock resistance sudden decrease of bending strength to $\Delta$T was not shown because intergranular large pore prevented sudden crack propagation.

• 한국세라믹학회지
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• 제32권1호
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• pp.113-119
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• 1995

The green body was fabricated by a new forming method, pressureless powder packaing forming method, and the characteristics of sintered specimen were investigated. It was found that alumina ceramics prepared by the present method showed porous structure with narrow pore size distribution, and in case of abrasive powder sintered body, compared with dry-pressed specimen, had the nearly same density. Especially, the specimen prepared with spray-dried granules showed the characteristic that granules were not either deformed or fractured during forming and sintering process. Therefore, it was found that this new forming method was effective method in fabrication of porous ceramics on account of easy control of porosity and pore size and its high thermal stability.

• 한국기계가공학회지
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• 제11권5호
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• pp.137-141
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• 2012

In order to increase recyclability of new material, aluminium-lithium alloy(Al2050-T84), the chip is compressed in the type of cylinder after machining. This study is to review the effect of environmental condition such as temperature change and salt during the transportation by sea on the corrosion at the surface and inside of the compressed chip, and an effective packing method is presented in this paper.

• 대한기계학회논문집A
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• 제24권10호
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• pp.2469-2476
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• 2000

The meshing of the domain has long been the major bottleneck in performing the finite element analysis. Research efforts which are so-called meshfree methods have recently been directed towards eliminating or at least easing the requirement for meshing of the domain. In this paper, a new meshfree method for solving nonlinear boundary value problem, based on the bubble packing technique and Delaunay triangle is proposed. The method can be efficiently implemented to the problems with singularity by using formly distributed nodes.