• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.3 no.3
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• pp.176-185
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• 1991

Pressure drop and flow characteristics through a filter medium have been investigated numerically. A basic model similar to the filter employed in a hard disk drive was established so that the inflow velocity was 0.1 m/s and the box size was $40mm{\times}50mm{\times}30mm$. The filter medium specifications were 0.38mm of thickness, $1{\mu}m$ of fiber diameter, 0.05 of packing density. And the filter medium was pleated by 10 within the filter box. Twenty-one sets of calculation were performed with different inlet velocities, pleated numbers, and packing densities from the basic model. As the result, it was found that the velocity after filter medium had maximum value at the rear of the upstream pleated line, but had minimum value at the rear of the downstream pleated line. This made the velocity distribution have sinusoidal form immediately after the filter medium. As the inlet velocity increased, the pressure drop increased linearly. But as the packing density increased the pressure drop increased quadratically.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.122-123
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• 2000

일반적으로 고형물을 함유하는 통조림 제조에 있어 고형물을 캔에 충진할 경우 물이나 시럽, 조미액 및 식용유 등 Packing medium을 첨가하는데 이 Packing medium 을 첨가하는 목적은 관내의 조미가 가능하고 가열살균하는데 대류전열의 매체로 작용하며 관내에 봉입되는 공기량을 줄일수 있고 관충격에 대하여 완충작용을 하는 역할이 있기 때문이기는 하나 관의 중량이 무겁게 되고 가용성 성분의 희석, 흡수와 팽윤에 따른 육질의 연화 등 단점이 되기도 한다. (중략)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.399-402
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• 2000

Very little information is known on the canning of fishery products by vacuum pack. In this paper, some fundamental process conditions for the canning of fishery products were investigated. Moisture-controlled mackerel pike, shrimp and oyster were packed in lacquered cans with spice and additives. After sealing, pressure of the cans were reduced by do-aeration through specially designed gas-tight silicone rubber plug previously attacked to the lid. On this investigation, vacuum can prior to thermal processing were set up to 15, 30, 45 and 60 cmHg, The higher vacuum in cans showed the more quick heat transfer in thermal processing. tinder 60 cmHg vacuum, the heat transfer was more quick than that of the conventional water packed products, Under 15 cmHg, however, the heat transfer was markedly increased by air which acted as an insulator in conductive heat transfer. These results demonstrated that high vacuum was essential secure for the heat processing in vacuum pack.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.3
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• pp.358-367
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• 1998

Since the performance of cooling tower is strongly dependent on the thermal performance of the packing, the evaluations of heat transfer rate and fan power from various packing have attracted intense interest. In the present study, two new packings have been devised and their performances have been compared with those of two existing packings to find better shape characteristic. It is found that one of the existing packings, which showed high heat transfer rate and medium fan power due to zig -zag flow passages and highly irregular surfaces, should be adapted.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.9
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• pp.1284-1296
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• 2004

In order to investigate effects of anisotropic fiber packing on stresses in composites, a Volume Integral Equation Method is applied to calculate the elastostatic field in an unbounded isotropic elastic medium containing multiple orthotropic inclusions subject to remote loading, and a Mixed Volume and Boundary Integral Equation Method is introduced for the solution of elastostatic problems in unbounded isotropic materials containing multiple anisotropic inclusions as well as one void under uniform remote loading. A detailed analysis of stress fields at the interface between the isotropic matrix and the central orthotropic inclusion is carried out for square, hexagonal and random packing of orthotropic cylindrical inclusions, respectively. Also, an analysis of stress fields at the interface between the isotropic matrix and the central orthotropic inclusion is carried out, when it is assumed that a void is replaced with one inclusion adjacent to the central inclusion of square, hexagonal and random packing of orthotropic cylindrical inclusions, respectively, due to manufacturing and/or service induced defects. The effects of random orthotropic fiber packing on stresses at the interface between the isotropic matrix and the central orthotropic inclusion are compared with the influences of square and hexagonal orthotropic fiber packing on stresses. Through the analysis of plane elastostatic problems in unbounded isotropic matrix with multiple orthotropic inclusions and one void, it will be established that these new methods are very accurate and effective for investigating effects of general anisotropic fiber packing on stresses in composites.

• Journal of the Korean Wood Science and Technology
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• v.2 no.3
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• pp.39-41
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• 1974

Bastard indigo, prevailing shrub species planted in erosion control work to constitute vegetation, is proved to be usefull for pulp material other than existing usage of green manure or fuel. Pulp made from bastard indigo is good enough for filler pulp though the quality of it is not remarkably excellent. (1) Sorts of paper possible to make from this pulp. Packing paper of medium grade. (general packing paper except heavy packing) (2) Traits of this pulp as for pulp material (A) It is more preferable than annual plants in these respects, ego collection, transport and storage of pulp material, and yield, freeness and chemical consumption of pulp. (B) Annual probable production of pulp material per ha from this plant is higher than that from long-term tree species or similar to that from fast growing species. (C) Its cultivation on eroded area is welcomed and consecutive annual production of material by copice method is also proved possible.

• Journal of the Korean Ceramic Society
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• v.31 no.9
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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.

• Journal of the Korea Safety Management & Science
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• v.14 no.4
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• pp.193-203
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• 2012

In the limitless competition era of the 21st century, cost reduction is being highlighted as one of survival strategies of businesses. The first item for cost reduction of businesses is logistical costs. The most keenly required thing for this is to remove unnecessary elements, and the best way to realize it to cut down processes using automatic facilities. Packing container in logistics is like a facility. This study is intended to analyze reduction of costs, improvement of business process and reduction of working force through standardization of standardization, and logistics effects through improvement of environmental images in enterprises.

• Korean Journal of Agricultural Science
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• v.31 no.2
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• pp.149-160
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• 2004

This study had carried out an analysis of leaf tobacco production cost by cost items, growing stages, and farm sizes per 10a to provide the basic data for determination of the purchasing price of leaf tobacco by KT&G. Considering the survey results of 12 tobacco farm households, the composition rates of production cost by items revealed as 7-10% for land service, 5-22% for depreciation, 13-25% for material costs, 50-65% for labour cost respectively. The production cost of leaf tobacco by growing stages were shown as 15.3% in nursery bed period, 32.3% in main growing period in field, 30.8% in harvesting period and 21.6% in packing period. The magnitude of wage expenditure was appeared as harvesting stage, packing stage, growing stage on main field and nursery bed stage in order. The amount of material costs were revealed as the growing stage in main field, harvesting stage, nursery bed stage and packing stage respectively. The production costs of leaf tobacco per 10a by farm sizes were shown as 1,615,879won for small farm, 1,446,896won for medium farm and 1,454,408won for large farm respectively. The production cost of leaf tobacco had shown decreasing tendency according to increasing farm sizes. To promote the international market competitiveness of leaf tobacco producing farms, labour saving production technologies and cost effective farm size to decrease tobacco production cost should be developed.

• Journal of the Korea Society for Simulation
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• v.16 no.4
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• pp.67-75
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• 2007

Radio Frequency IDentification(RFID) is in the limelight of fields of military, delivery and library management as an alternative or barcode system. However, it is restricted within product manufacturing, sales and delivery. In this paper, we apply RFID technology into process, especially packing process management to gauge RFID applicability. To verify beneficial features of RFID, we simulate RFID-adopted packing process. As a result, we demonstrate the effectiveness of a RFID-based Process Improvement In manufacturing process. The results of performance evaluations demonstrate that the proposed RFID-based Process Improvement reduces the labour time, labour cost and material cost. Furthermore, we analyze the validity of RFID-based Process Improvement by RFID cost.