• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.12
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• pp.1926-1932
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• 2001

In this second part of the paper, the automatic mesh generation and remeshing algorithm using bubble packing method is applied to the nonlinear problem. The remeshing/refinement procedure is necessary in the large deformation process especially because the mesh distortion deteriorates the convergence and accuracy. To perform the nonliear analysis, the transfer of state variables such as displacement and strain is added to the algorithm of Part 1. The equilibrium equation based on total Lagrangian formulation and elasto-viscoplastic model is used. For the numerical experiment, the upsetting process including the contact constraint condition is analyzed by two refinement criteria. And from the result, it is addressed that the present algorithm can generate the refined meshes easily at the largely deformed area with high error.

• Journal of the Korean Ceramic Society
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• v.36 no.6
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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.

• Journal of the Korean Ceramic Society
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• v.36 no.6
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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.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.5
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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.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.835-840
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• 2000

The purpose of this study is developing concrete Mixing & placing method that could be adjusted to vertical joint at top-down method. Basic test was consists of general, high fluidity, and high quality mixing concretes and Mock-up test had several placing ways, placing positions. They were examined several placing ways, placing positions with Mock-up model comparison with three mixing concrete to know fluidity characterics. Used with Mock-up model to know packing ability from placing ways and positions. The result of the study like this; High fluidity and High quality concretes show favorable packing ability, especially, in sheath placing way. It was expected to good result in next planned real structure test.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.2
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• pp.47-53
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• 2004

In this experiment the effects of the packing structure of pigment on the surface characteristics (smoothness and gloss) of coated paper are studied. Four different kinds of inorganic pigments(clay), ground calcium carbonate(GCC), two of precipitated calcium carbonates(PCC), and two organic pigments(solid bead and hollow type) were used. The method of measuring the relative sediment volume(RSV) was used to analyze the packing structure of coating layer. The relative sediment volume was measured, using the pressure dewatering dry-cake method(PDDM) and centrifuge method. Also, the particle size distribution of coating pigment was determined. The results showed that small amount of organic pigment, added to inorganic pigment, improved smoothness and its effect was greater when GCC was used as inorganic pigment. The efficiency of organic pigment depended upon the inorganic pigment since the organic pigment is packed in the pores formed by the inorganic pigment.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.250-252
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• 2022

As immersive video contents have started to emerge in the commercial market, research on it is required. For this, efficient coding methods for immersive video are being studied in the MPEG-I Visual workgroup, and they released Test Model for Immersive Video (TMIV). In current TMIV, the patches are packed into atlas in order of patch size. However, this simple patch packing method can reduce the coding efficiency in terms of 2D encoder. In this paper, we propose patch packing method which pack the patches into atlases by using the similarity of each patch for improving coding efficiency of 3DoF+ video. Experimental result shows that there is a 0.3% BD-rate savings on average over the anchor of TMIV.

• Journal of KIISE:Databases
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• v.31 no.2
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• pp.122-131
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• 2004

Traditional works on indexing have been suggested for low dimensional data under dynamic environments. But recent database applications require efficient processing of huge sire of high dimensional data under static environments. Thus many indexing strategies suggested especially in partitioning ones do not adapt to these new environments. In our study, we point out these facts and propose a new partitioning strategy, which complies with new applications' requirements and is derived from analysis. As a preliminary step to propose our method, we apply a packing technique on the one hand and exploit observations on the Minkowski-sum cost model on the other, under uniform data distribution. Observations predict that unbalanced partitioning strategy may be more query-efficient than balanced partitioning strategy for high dimensional data. Thus we propose our method, called CSP (Cyclic Spliced Partitioning method). Analysis on this method explicitly suggests metrics on how to partition high dimensional data. By the cost model, simulations, and experiments, we show excellent performance of our method over balanced strategy. By experimental studies on other indices and packing methods, we also show the superiority of our method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.6
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• pp.1490-1495
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• 1998

Call packing has been recognized as a routing scheme that significantly reduces the blocking probability of connection requests in a circuit-switched Clos multistage interconnection network. In this paper, for the first time, a general analytical model for the point-to-point blocking probability of the call-packing scheme applied to Clos networks is developed. By introducing a new parameter called the degree of call packing, the model can correctly estimate the blocking probability of both call-packing and random routing schemes. The model is verified by computer simulation for various size networks and traffic conditions.

• The KIPS Transactions:PartC
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• v.16C no.5
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• pp.555-562
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• 2009

In malware accident investigation, the most important thing is detection of malicious code. Signature based anti-virus softwares have been used in most of the accident. Malware can easily avoid signature based detection by using packing or encryption method. Because of this, packed file detection is also important. Detection methods can be divided into signature based detection and entropy based detection. Signature based detection can not detect new packing. And entropy based detection has a problem with false positive. We provides detection method using entropy statistics of entry point section and 'write' properties of essential characteristic of packed file. And then, we show packing detection tool and evaluate its performance.