• Title/Summary/Keyword: Packing

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Computer Simulation of Three Dimensional Particle Packing (콜로이드 입자의 3차원적인 적층에 대한 컴퓨터 시뮬레이션)

  • ;David M. Martin
    • Journal of the Korean Ceramic Society
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    • v.34 no.9
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    • pp.979-985
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    • 1997
  • The three-dimensional particle packing process is simulated using Lahey FORTRAN 90 as a programming language running on a personal computer. Particle clusters constructed with rearrangement which occurs during packing have higher average coordination number and packing density than particle clusters rearranged after packing. Rearranging particles can not completely block other particles from entering pore volume in 3-dimensional packing unlike in 2-dimensional packing. It is found that there is a region of instability where lower packing density results from the destruction of the ordered packing.

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Loose and Dense Aggregate Particle Packing Models in Cement and Concrete

  • Kim, Jong-Cheol;Lim, Chang-Sung;Auh, Keun-Ho
    • The Korean Journal of Ceramics
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    • v.6 no.1
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    • pp.1-5
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    • 2000
  • Particle packing properties are important to develop high technology products in the field of cement and concrete. Two types of particle packing models for aggregates with sand and cement were introduced: the loose and the dense aggregate packing. Aggregate packing models with randomly generated sand and cement particles in the interstices of aggregates fit the Furnas model very well. Different aggregate models show different packing properties with the experimental results. Main reason for the difference with the experimental results is due to sand rearrangement in the loose aggregate packing model and to aggregate relaxation in the dense aggregate packing model. In the experimental situation, aggregates seem to be more disordered and have a relaxed packing structure in the dense packing, and sands seem to have a more rearranged packing structure in the loose packing model.

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Development of Automatic Packing System of One Station for Fasteners(II) : Packing System Manufacture and Performance Test (원 스테이션 파스너 자동포장기 개발(II) : 제작 및 성능검증)

  • Kim, Yong-Seok;Jeong, Chan-Se;Yang, Soon-Young
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.20 no.5
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    • pp.653-658
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    • 2011
  • In general, the purpose of packaging fasteners is a series of management activities to maintain the condition at the time of production until they get delivered to the end user. An automatic packing system for fasteners is consisted of bucket conveyor, slide feeder, vision inspection system, box-magazine conveyor system and automatic packing machine. Also, the automatic packing machine is consisted of six modules including charging device, clamping/opening device, sealing/cutting device, feeding/air-shower device, supplying/adjusting device and device frame, etc. In this paper, we proposed an automatic packing mechanism of the one station concept for packing work of fastener objects where the continuous batch work is performed in a finite space. The proposed one-station packing mechanism has been optimized through mechanical, dynamical, structural and fluid analyses. And it had been manufactured as the prototype of automatic packing machine. The field test for validation of performance was performed directly at the production line of bolt and screw. In the field test, this packing machine showed an efficiency of about 4.5 times the manual operation. It also showed 30% reduction in the consumption of packing materials compared to the manual operation. This automatic packing machine for fastener objects will be commercialized soon.

Effects of Nasal Packing on the Eustachian Tube Function (Nasal Packing이 이관기능에 미치는 영향)

  • 손학순;백문찬;양초영;이준희;김종애
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1979.05a
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    • pp.5.2-6
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    • 1979
  • It is clinically well-known observation that Nasal packing is associated with the eustachian tube dysfunction, and this study seldom appeared in the literature. In our country, Nasal Surgery requiring Nasal packing is still the most frequent operation in the field of otorhinolaryngology and it is our interest to study this effects of Nasal packing on the eustachian tube function. Using tympanometry, we experienced eustachian tube dysfunction in 40 patients (80 ears) with anterior packing due to Nasal Surgery and epistaxis and in 13 patients (26 ears) with anterior packing and posterior packing due to epistaxis. The results were as fllows; 1) Thirty of the 80 ears (37%) in the patients with anterior packing revealed reduction in middle ear pressure, of which 16 ears (20%) demonstrated negative middle ear pressure of greater than 100mm H20. 2) Fifteen of the 26 ears (50.7%) in the patients with posterior packing revealed reduction in middle ear pressure, of which 11 ears (42.3%) demonstrated negative middle ear pressure of greater than l00mm H20. 3) Posterior packing is associated with a greater incidence of eustachian tube dysfunction than anterior packing. 4) The eustachian tube dysfunction associated with Nasal packing is temporary and this function is returned to normal within 2 to 9 days after removal of the packing.

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A Study on Charateristic of Modern Packing, 25mm NSW-ring, ppm by Absorption of NH3 gas (25mm NSW-ring, pp.를 충진한 충진탑에서 암모니아 흡수에 의한 유해가스 처리시 충진물의 특성연구)

  • 신은재;박진식
    • Journal of Environmental Science International
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    • v.6 no.4
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    • pp.391-397
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    • 1997
  • The study was carried out to demonstrate the superiority of used packing in view of energy saving and efficiency of mass transfer, comparing with conventional packing. The results are as follows : 1. Owing to low Pressure drop under high load. 25mm NSW-ring, pp. can cause energy saving 2. The unique magnitudes of used packing are as follows $C_G$=5.78, m=0.67, n=0.46 3. Used packing can make high efficiency including energy saving because of low pres sure drop per the number of transfer unit. To rate the characteristic of packing, It should be carried out that the measurement of pressure drop per packing height and per the number of transfer unfit. This study demonstrated the superiority of used packing by carring out above experiment and could be used as basic reference for design and predicting efficiency of packing tower which is tilled with same packing.

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A Study on Conformity of Packing in International Sales of Contract (국제물품매매계약에서 포장의 계약적합성에 관한 연구)

  • Kim, Jae-Seong;Park, Se-Hun
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.54
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    • pp.123-144
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    • 2012
  • Seller shall deliver the goods with a perfect condition of packing or container in international trade. Unless otherwise seller shall warranty that the goods arrive at destination with a safe and economic value. Buyer may ask packing is to be made in specific condition or refuse to accept when the packing is not made in accordance with trade customs between among merchants. Especially packing is to be considered under the local law and process. Sometimes tax will be added to specific condition of packing for example glasses, metal sheet or others. Warning signs shall be included as form of both words and diagrams, and be in form of ensuring understanding in the local market. Wide range of warning signs can be used for communications and understanding of packing. Packing of a product can usefully symbolize a range of product information, or any relevant warnings, and give an opportunity for displaying messages of promoting the company and the goods. The seller may choose the best method to maintain its value but find a way to reduce packing cost, size for convenience during delivery, design, and local customs. There are many things to be considered for packing to seller. The purpose of packing is to protect the goods itself and to maintain its economic value during storage, delivery, transshipment, and distribution to end users.

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A Study on the Turbine Performance in the steam seal variable clearance packing type of Steam turbine (증기터빈의 가변패킹 형태에 따른 터빈성능 평가에 관한 연구)

  • Kweon, Y.S.;Suh, J.S.
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.1676-1681
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    • 2004
  • The main reason for applying positive pressure variable clearance packing in fossil power plant is high efficiency and energy saving movement in the government. This study intends to analyze the turbine efficiency through the shaft packing improvement in thermal power plant and makes its comparison to that of the each packing type

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PACKING DIMENSION OF MEASURES ON A RANDOM CANTOR SET

  • Baek, In-Soo
    • Journal of the Korean Mathematical Society
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    • v.41 no.5
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    • pp.933-944
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    • 2004
  • Packing dimension of a set is an upper bound for the packing dimensions of measures on the set. Recently the packing dimension of statistically self-similar Cantor set, which has uniform distributions for contraction ratios, was shown to be its Hausdorff dimension. We study the method to find an upper bound of packing dimensions and the upper Renyi dimensions of measures on a statistically quasi-self-similar Cantor set (its packing dimension is still unknown) which has non-uniform distributions of contraction ratios. As results, in some statistically quasi-self-similar Cantor set we show that every probability measure on it has its subset of full measure whose packing dimension is also its Hausdorff dimension almost surely and it has its subset of full measure whose packing dimension is also its Hausdorff dimension almost surely for almost all probability measure on it.

A Study on the Effects of Filling and Packing Phases on the Injection Modeling (사출성형에 대한 충전과 보압과정의 영향에 관한 연구)

  • 김현필;김용조
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.04a
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    • pp.112-118
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    • 2002
  • Injection molding process factors such as molding temperature, injection pressure, flow rate and flow velocity, must be controlled properly in filling and packing phases in the injection molding process. In this study, effects of these factors on the injection molding were investigated through the flow analysis fur the filling and packing phases. Molding troubles like flow mark, weld line, sink mark, short shot and warpage can be caused by these injection molding process factors. Among them, the short shot was caused by that the packing pressure could not reach properly to the filling end part in the packing phase and hence the flow rate could not be supplied to the full. In addition, as the flow rate for the volumetric shrinkage during the frozen phase could not be supplied properly by the packing pressure, the short shot appeared. Here, the volumetric shrinkage reduced with increasing the packing pressure and also the warpage of molded part increased with increasing the packing pressure.

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A Study on the Effects of Filling and Packing Phases on Injection Molding Process (충전과 보압과정이 사출성형공정에 미치는 영향에 관한 연구)

  • 김현필;김용조
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.11 no.4
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    • pp.44-53
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    • 2002
  • Injection molding process factors such as molding temperature, injection pressure, flow rate and flow velocity, must be controlled properly in filling and packing phases in the injection molding process. In this study, effects of these factors on the injection molding were investigated through the flow analysis for the filling and packing phases. Molding troubles like flow mark weld line, sink ma가 short shot and warpage car be caused by these injection molding process factors. Among them the short shot was caused by the fact that the packing pressure could not reach properly to the filling end part in the packing phase and hence the flow rate could not be supplied to the full. In addition as the flow rate for the volumetric shrinkage during the f개zen phase could not be supplied Properly by the packing pressure, the short shot appeared. Here, the volumetric shrinkage reduced with increasing the packing pressure and also the warpage of molded part increased with increasing the packing Pressure.