• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.10
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• pp.775-780
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• 2002

An experimental study on the characteristics of several kinds of packing materials was carried out in order to get the optimum design data for the packed-type rectification system of an NH$_3$/$H_2O$ GAX absorption heat pump. Several suitable packing materials were examined and the bulk of steel wire was shown as the most effective packing material in rectifier. The optimum volumetric ratio of packed steel wire in rectifier was obtained as around 36%. The performance results can be adapted in rectifier design of absorption heat pump.

• Plant Resources
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• v.5 no.1
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• pp.70-73
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• 2002

To develop an optimal storage method of root of Angelica acutiloba Radix, which has been grown as major herbal medicine material to be cultivated, root of Angelica acutiloba 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. In conclusion, vacuum packing and complete sealing with polyethylene film appears to be most optimal for storage of Angelica acutiloba Radix.

• Journal of Navigation and Port Research
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• v.30 no.7
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• pp.561-566
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• 2006

In this paper, we propose a new ship scheduling set packing model considering limited risk or variance. The set packing model is used in many applications, such as vehicle routing, crew scheduling, ship scheduling, cutting stock and so on. As long as the ship scheduling is concerned, there exits many unknown external factors such as machine breakdown, climate change and transportation cost fluctuation. However, existing ship scheduling models have not considered those factors apparently. We use a quadratic set packing model to limit the variance of expected cost of ship scheduling problems under stochastic spot rates. Set problems are NP-complete, and additional quadratic constraint makes the problems much harder. We implement Kelley's cutting plane method to replace the hard quadratic constraint by many linear constrains and use branch-and-bound algorithm to get the optimal integral solution. Some meaningful computational results and comments are provided.

• Structural Engineering and Mechanics
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• v.15 no.1
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• pp.135-149
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• 2003

The bubble packing method is implemented for adaptive mesh generation in two and three dimensions. Bubbles on the boundary of a three-dimensional domain are controlled independently of the interior bubbles in the domain, and a modified octree technique is employed to place initial bubbles in the three-dimensional zone. Numerical comparisons are made with other mesh generation techniques to demonstrate the effectiveness of the present bubble packing scheme for two- and three-dimensional domains. It is shown that this bubble packing method provides a high quality of mesh and affordable control of mesh density as well.

• Journal of the Korean Society of Safety
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• v.8 no.4
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• pp.120-126
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• 1993

This work was carried out to investigate the effects of solid mass flow rate, mean particle diameter and mesh number of screen packing material on minimum carrying velocity, which defined as the superficial gas velocity of the upper limit of chocking phenomenon. Vertical pneumatic conveying was studied on a 4.6cm 1. D. pipe, 180cm in length. Experiments were performed in both the empty and the screen-packed pipe. It was also examined the effect of superficial gas velocity, solid mass flow, mean particle diameter, and mesh number of packing material on pressure drop. Minimum carrying velocity in screen packed-pipe was lower than that in an empty pipe. besides minimum carrying velocity was decreased with increase in mesh number of screen packing material. The pressure drop In vortical packed-pipe was Increased with superficial gas velocity, mean particle diameter, and mesh number of screen packing material.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.105-110
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• 2005

The penalty method has been widely applied to analyses of incompressible fluid flow. However, we have not yet found any prior studies that employed penalty method to analyze compressible fluid flow. In this study, with an eye on the apparent similarity between the slight compressible formulation and the penalty formulation, we have proposed a modified approximate approach that can analyze compressible packing process using the penalty parameter, which is an improvement on an earlier formulation (KSME, 2004B). Based on the assumption of the isothermal flow, a set of reference solutions was obtained to verify the validity of the proposed scheme. Furthermore, we have applied the proposed scheme to the analysis of the packing process of different cases.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.1
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• pp.95-103
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• 2015

Objectives: This study was conducted in order to better understand the conceptual model and Stoffenmanager nano module and apply it to the synthesis and packing processes of nanomaterials. Methods: Site visits were conducted to five nanomaterial production processes. Product and exposure variables were investigated in these workplaces. Hazard banding and exposure classification of the synthesis and packing processes of nanomaterials were conducted using documents and the website of Stoffenmanager Nano. Results: The five sites featured different products, packing tasks, ventilation and local exhaust, and others. The hazards for nano-nickel and copper were classified as E. The hazards for both fumed silica and indium tin oxide were classified as D. The hazard for spherical silica was classified as C. The exposure classes in the synthesis process of nanomaterials ranged from 2 through 4. The exposure classes in the packing process of nanomaterials ranged from 1 through 4. Conclusions: Application of Stoffenmanager nano to the synthesis and packing processes of nanomaterials helped to better understand the control level of the work environment and to suggest appropriate actions. The comparison of each process showed the effect of the production process and handling of solids and ventilation on exposure class.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.11
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• pp.2355-2363
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• 2002

The accompanying paper, Part 1, has presented the physical modeling and basic numerical analysis results of both the flow-induced and thermally-induced residual stress and birefringence in injection molded center gated disks. The present paper, Part II, has attempted to investigate the effects of various processing conditions of injection/compression molding process on the residual stress and birefringence. The birefringence is significantly affected by injection melt temperature, packing pressure and packing time. Birefringence in the shell layer increases as melt temperature gets lower. The inner peak of birefringence increases with packing time and packing pressure. On the other hand, packing pressure, packing time and mold wall temperature affect the thermally-induced residual stress rather significantly in the shell layer, but insignificantly in the core region. Injection/compression molding has been found to reduce the birefringence in comparison with the conventional injection molding process. In particular, mold closing velocity and initial opening thickness in the compression stage of injection/compression molding process have significant effect on the flow-induced birefringence, but not on tile thermal residual stress and the thermally induced birefringence.

• Korean Journal of Poultry Science
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• v.23 no.4
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• pp.203-207
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• 1996

This experiment was carried out to find out the effects of packing methods on shelf-life and hy-giene of breast and thigh meats in chicken. The carcass weights were about 1.6 kg per bird, and chilled by air spray method. The breast and thigh meats were packed by either vacuum or atmosphere packing methods. Samples were analyzed at 1, 4, 8, 12 and 16 wk after quick freezing at -45˚C for 35 min. Regardless of packing method. The thiobarbituric acid(TBA) values of thigh meats after 1 wk of storage were higher than those of breast meats. The TBA values of both treatments were increased as storage period extended. In addition, the TBA values of vacuum packed meats were lower than those of atmosphere packed meats. The VBN(volatile basic nitrogen) values, regardless of packing method, at 1 wk of storage were higher than those of breast meats. The VBN contents of breast and thigh meats after 16 wk of storage increased markedly, but failed to show significant difference between the two packaging methods. Total plate counts of breast and thigh meats were increased gradually as storage period extended, and the total plate count of breast meat was higher than that of thigh meat. The coliform bacteria were not detected until 16 wk after storage.

• Journal of Korean Society of Rural Planning
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• v.9 no.4 s.21
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• pp.53-57
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• 2003

This study was carried out in order to develop brand and packing design for agricultural products of Dangjin County. Current packing designs such as rice packs, cucumber box, sweet potato box, apple box and kimchi pack were collected from agricultural cooperatives in Dangjin area. For those packing designs, corporate identity(CI) clinic was conducted and the results obtained were as follows: There are varieties of names, colors, fonts, and sizes far the same items, so that consumers could not easily find and understand those CIs of agricultural products in Dangjin County. Among others, those packages are needed CI clinic such as the packages of Dangjin apple(Song-ak Agricultural Cooperative), Dangjin sweet potato(Seok-moon A. C.) and rice(Daehoji A. C., Shinpyeong A. C.). However, the packing design of Hyang-chae-bang Kimchi is evaluated as good design. For CI clinic, it is desirable to develop unique and united brand name and simple design for the packages such as the case of 'Anseong-Matzum' of Anseong City, which is unique and united brand name with simple design enhancing synergy effect for agricultural marketing.