• Journal of the Korean Operations Research and Management Science Society
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• v.22 no.2
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• pp.125-137
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• 1997

We are concerned with the packing policy determines the optimal packing of products with variable sizes to minimize the penalty costs for idle space and product spliting. Optimal packing problem is closely related to the optimal packet/record sizing problem in that randomly generated data stream with variable bytes are divided into a unit of packet/record for transmitting or storing. Assuming the product size and the production period are independently determined by renewal process, we can approximate the renewal process and formulate the optimization problem that minimize the expected packing cost for a production period. The problem is divided into two cases according to whether a product is allowed to split or not. Computational results for various distributions will be given to verify the approximation procedure and the resulting optimization problem.

• Bulletin of the Korean Mathematical Society
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• v.52 no.5
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• pp.1489-1493
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• 2015

For a subset $E{\subseteq}\mathbb{R}^d$ and $x{\in}\mathbb{R}^d$, the local Hausdorff dimension function of E at x and the local packing dimension function of E at x are defined by $$dim_{H,loc}(x,E)=\lim_{r{\searrow}0}dim_H(E{\cap}B(x,r))$$, $$dim_{P,loc}(x,E)=\lim_{r{\searrow}0}dim_P(E{\cap}B(x,r))$$, where $dim_H$ and $dim_P$ denote the Hausdorff dimension and the packing dimension, respectively. In this note we give a short and simple proof showing that for any pair of continuous functions $f,g:\mathbb{R}^d{\rightarrow}[0,d]$ with $f{\leq}g$, it is possible to choose a set E that simultaneously has f as its local Hausdorff dimension function and g as its local packing dimension function.

• The KIPS Transactions:PartA
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• v.10A no.1
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• pp.43-48
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• 2003

Two-dimensional packing algorithm can be used for allocating submeshes in mesh multiprocessor systems. Previously, we developed an efficient packing algorithm called TP heuristic, and showed how the results of the packing could be used for allocating submeshes. In this paper, we present theoretical performance bounds for TP heuristic. We also present a parallel version of the algorithm that consumes reduced time when it is executed by multiple processors in mesh multiprocessors.

• Plant Resources
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• v.5 no.2
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• pp.114-117
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• 2002

To develop optimal storage method of root of Peucedani Radix, which has been grown as major cultural herbal medicine material, root of Peucedani Radix was stored for 10 months with different packing materials and sealing methods. The loss in dry weight as influenced by packing materials and sealing methods was the lowest at vacuum packing and followed by complete sealing methods with transparent polyethylene film. The ratio of root rot during the storage period was not significantly different between packing materials but was significantly different between sealing conditions. Conclusively vacuum packing and complete sealing with polyethylene film appears to be optimal for storage of Peucedani Radix.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1030-1033
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• 2003

The packing-free piston has become widely distributed in certain branches of instrument making and precision machine building. A large number of the most diversified instruments are now being constructed on the principle of the packing-free piston like piston manometers, vacuum manometers, hydraulic machines, dynamometers. hardness measuring instruments. power indicators, hydraulic scales, and many others. In spite of the widespread application of systems with a packing-free piston, there were practically no special papers to the theory and practice of the application of such systems. This paper describes the theoretical approaching method to get the pressure distribution profile between the piston and cylinder using finite element method.

• Plant Resources
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• v.5 no.3
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• pp.224-227
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• 2002

To develop optimal storage method of root of Zingiberis Rhizoma, which has been grown as major cultural herbal medicine materials, root of Zingiberis Rhizoma, was stored for 10 months with different packing materials and sealing methods. The loss in dry weight as influenced by packing materials and sealing methods was the lowest at vacuum packing and followed by complete sealing methods with transparent polyethylene film. The ratio of root rot during the storage period was not significantly different between packing materials but was significantly different between sealing conditions. Conclusionally, vacuum packing and complete sealing with polyethylene film appears to be optimal for storage of Zingiberis Rhizoma.

• Plant Resources
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• v.4 no.2
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• pp.102-106
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• 2001

To develop optimumal storage method of root of Bupleurum falcatum Radix grown on major cultural herbal medicine materials, root of Bupleurum falcatum Radix was stored for 10 months with different packing materials and sealing methods. The loss in dry weight as influenced by packing materials and sealing methods was the lowest at vacuum packing and followed by complete sealing methods with transparent polyethylene film. The ratio of root rot during the storage period was not significantly different between packing materials but was significantly different between sealing conditions. Conclusionally, vacuum packing and complete sealing with polyethylene film appears to be optimal for storage of Bupleurum falcatum Radix.

• Journal of Korean Institute of Industrial Engineers
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• v.34 no.4
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• pp.470-480
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• 2008

Loading steel coil products on a specialized packing case called pallet can be represented as a bin-packing problem with the special constraint where objects should be loaded on designated positions of bins. In this paper, under assuming that there exist only two types of objects, we focus on finding the optimum number of positions in a bin which minimizes the number of bins needed for packing a collection of objects. Firstly, we propose a method to decide the number of positions and prove that the method is optimum. Finally, for the packing problem using bins designed by the method, we show that the well-known algorithm, First-Fit Decreasing(FFD), is the optimum algorithm.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.214-219
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• 2005

Pressure distribution in the cavity during injection molding affects part quality. In this study pressure distributions in the runner, near gate in the cavity, and end of ail in the cavity have been measured using direct pressure sensors for various molding conditions. Molding conditions were injection speed, injection pressure, packing time from filing stage, and packing pressure. Through experiments it was realized that the packing time from filling stage and packing pressure are the dominant factors on the part quality such as part shrinkage. Experimental results have been compared with computer simulations.

• 한국금형공학회:학술대회논문집
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• 2008.06a
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• pp.103-109
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• 2008

The sink mark on boss parts is generated by the volumetric shrinkage that is caused by both the molding thickness and the boss wall thickness. The volumetric shrinkage is caused by packing pressure and its amount tends to decrease by increasing the packing pressure. The packing pressure can therefore increase the flow rate to a boss part and causes the depth of sink mark to increase. As the molding thickness and the boss wall thickness in the boss part can increase the part volume, these may yield bad solidifying and also extend the molding cycle. In this paper, both the injection molding test and the flow analysis were carried out to investigate the effect of sink mark that was generated in the boss wall thickness of injection molded products. The sink mark could also be caused by thickness ratio of boss part. For a given thickness ratio of boss, several molding process parameters such as packing pressure, packing time and melt temperature, affecting to generation of the sink mark were discussed