• 한국세라믹학회지
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• 제34권9호
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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.

• The Korean Journal of Ceramics
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• 제6권1호
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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.

• 한국생산제조학회지
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• 제20권5호
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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.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1979년도 제13차 학술대회 연제순서 및 초록
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• pp.5.2-6
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• 1979

Nasal packing이 이관 기능장애를 일으킨다는 것은 임상적으로 잘 알려진 사실이나 이에 대한 연구는 드문 것으로 안다. 우리나라에서는 아직도 Nasal packing을 요하는 비수술이 이비인후과 영역에서 가장 흔한 수술이기 때문에 Nasal packing이 이관 기능에 미치는 영향을 연구한다는 것은 흥미있는 문제라고 생각된다. 저자는 비수술과 비출혈로 Anterior packing을 시행한 40명의 환자(80 ears)와 비출혈로 posterior packing을 시행한 13명의 환자(26 ears)로부터 Tympanometry을 측정하여 이관 기능장애를 연구하여 다음과 같은 결과를 얻었다. 1) Anterior packing을 시행한 환자의 80 ears 중 30 ears(37%)에서 중이내압의 감소를 보였으며 그 중 16 ears(20%)에서 $100mmH_2O$ 이상의 중이내 음압을 보였다. 2) Posterior Packing을 시행한 환자의 26 ears 중 15 ears(50.7%)에서 중이내압의 감소를 보였으며 그중 11 ears(42.3%)에서 $100mmH_2O$ 이상의 중이내 음압을 보였다. 3) Posterior packing이 Anterior packing보다 더 높은 빈도의 이관 기능장애를 보였다. 4) Nasal packing으로 인한 이관 기능장애는 packing 제거 후 2일에서 9일내에 정상으로 회복됨을 볼 수 있었다.

• 한국환경과학회지
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• 제6권4호
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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.

• 무역상무연구
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• 제54권
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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.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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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

• 대한수학회지
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• 제41권5호
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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.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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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.

• 한국공작기계학회논문집
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• 제11권4호
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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.