• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1254-1255
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• 2006

For precise property control of sintered products, it is important to understand accurately the packing density of the powder. We developed a packing simulation program that could make a packed bed of spherical particles having particle size distribution. In addition, the influence of the particle shape of the actual powder on the packing density was quantitatively analyzed. The predicted packing densities corresponded well to the actual data.

• 한국정밀공학회지
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• 제31권1호
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• pp.9-13
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• 2014

The molding process can be divided into five separate steps: plastification, injection, holding, cooling, and finally ejection. In the plastic injection molding, the effect factor such as mold temperature, injection speed, packing pressure and inhomogeneous cooling under packing process affects both the article dimension and physical characteristics. Especially, the packing pressure is the most critical factor to affect molded articles quality among the packing parameters. In this paper, the CAE simulation considering the molding condition is performed to predict the faulty cause which appears in the packing process between cavities of injection molding machine. From the results of CAE simulation, the packing phenomena according to the product form and the gate position was investigated to improve the article quality and minimize the various molding defects. The effect of packing pressure and gate number on the injection molding was discussed.

• 한국생산제조학회지
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• 제20권3호
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• pp.335-341
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• 2011

In this paper, we proposed an automatic packing mechanism of one station concept for fastener objects where the continuous work is performed in a finite space. The proposed packing mechanism is composed of supporting frame, feeding supply, air shower device, clamping/opening device, batch charging device, sealing/cutting device and supply adjusting device. And, these mechanisms have been modularized through mechanical, dynamical, structural and fluid optimized design using the SMO(SimDesigner Motion) analysis module. Also, the virtual prototype was carried out using the 3-D CAD program. The packing process is consisted performed in the order of feeding, clamping, bottom sealing, cutting, opening, object charging, closing and the upper sealing. And the time of these cycles were designed to be completed in 15-20 seconds. This packing mechanism will be created as a prototype in the near future. In addition, it will be applied to the production scenes after going through a field test for the validation of performance.

• Journal of Computational Design and Engineering
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• 제1권2호
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• pp.140-151
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• 2014

Storing, and the loading and unloading of materials at production sites in the manufacturing sector for mass production is a critical problem that affects various aspects: the layout of the factory, line-side space, logistics, workers' work paths and ease of work, automatic procurement of components, and transfer and supply. Traditionally, the nesting problem has been an issue to improve the efficiency of raw materials; further, research into mainly 2D optimization has progressed. Also, recently, research into the expanded usage of 3D models to implement packing optimization has been actively carried out. Nevertheless, packing algorithms using 3D models are not widely used in practice, due to the large decrease in efficiency, owing to the complexity and excessive computational time. In this paper, the problem of efficiently loading and unloading freeform 3D objects into a given container has been solved, by considering the 3D form, ease of loading and unloading, and packing density. For this reason, a Group Packing Approach for workers has been developed, by using analyzed truck packing work patterns and Group Technology, which is to enhance the efficiency of storage in the manufacturing sector. Also, an algorithm for 3D packing has been developed, and implemented in a commercial 3D CAD modeling system. The 3D packing method consists of a grouping algorithm, a sequencing algorithm, an orientating algorithm, and a loading algorithm. These algorithms concern the respective aspects: the packing order, orientation decisions of parts, collision checking among parts and processing, position decisions of parts, efficiency verification, and loading and unloading simulation. Storage optimization and examination of the ease of loading and unloading are possible, and various kinds of engineering analysis, such as work performance analysis, are facilitated through the intelligent 3D packing method developed in this paper, by using the results of the 3D model.

• 한국안전학회지
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• 제14권3호
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• pp.101-109
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• 1999

This study attempts to analyse the solid mixing in the feeder and the packing effect for pressure fluctuations in the fluidized bed. To study the mixing characteristics of solid in vibrating feeder for the stable operations of fluidized combustion, the system consisted of two groups of particles such that fine particles were located on the top of the coarse particles before vibratory mixing had started. The effects of packing materials on the pressure fluctuations in a fluidized bed were analysed by using a statistical method to interpret the behavior of fluidized bed. The experiments were carried out in a fluidized bed of 6.7cm-ID, and the experimental variables were particle sizes, of 115 to 1,015$\mu\textrm{m}$ in diameter and the multi-sized particles haying Rosin-Rammler and Gaussian distributions. The settled bed heights of particles to diameter ratios (L/D) were ranged from 0.5 to 2.0. And fluidizing of particles was carried out by air. The packing materials used were screen packing, and the properties of the pressure fluctuations in the fluidized bed were measured by a differential pressure transducer. The properties of the pressure fluctuations calculated were the mean, the standard deviation, and the major frequency of the power spectral density functions. From the characteristics of fluidizing, it was found that the standard deviation of pressure fluctuations could be effectively used to explain the fluidized phenomena, and the packing materials affected severely the properties of the pressure fluctuations. As a result, from the interpretation by spectral analysis, the effects of measuring radius of pressure fluctuations on standard deviation were constant in the case of the fluidized bed with and without packing materials. However, the effects of measuring the height of pressure fluctuations on standard deviations were linear increasing for the fluidized bed with packing materials, but were constant for the fluidized bed without packing materials at 4.5cm above the gas distributor. The major frequency of pressure fluctuations was found to be nearly independent of fluidized system. Also, the major frequency of pressure fluctuations decreased with increasing packing size, and it had maximum value at 10% of the packing amount.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1993년도 춘계학술대회논문집
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• pp.100-109
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• 1993

To investigate the work-relatedness of carpal tunnel syndrome of some workers at packing department in a rayon manufacturing company, reseracher studied the symptoms and physical sign related to carpal tunnel syndrome of the workers at packing, ysrning, and washing department. The results are as follows: 1. By the results of ergonomic study, the packing work had the considerable probability to develop the carpal tunnel syndrome. 2. The prevalences of symptoms, physical sign and case by definition were higher in woman workers than in man workers. 3. In female workers, the age-agjusted prevalence rates of symptoms were 11.6/1, 000 in workers at washing department, 111.6/1, 000 in workers at packing department, and 70.1/1, 000 in workers at yarning department. In male workers, the age- adjusted rates of symptoms were 92.1/1, 000 in workers at washing department, 210.1/1, 000 in workers at packing and delivery department, and 0.0/1, 000 in workers at yarning department. 4. In female workers, the age-adjusted prevalence rates of physical signs were 119.5/1, 000 in workers at washing department, 104.4/1, 000 in workers at packing department, and 84.5 in workers at yarning department. In male workers, the age-adjusted rates of physical signs were 65.7/1, 000 in workers at washing department, 59.0/1, 000 in workers at packing and delivery department, and 176.9/1, 000 in workers at yarning department. 5. In female workers, the age- adjusted prevelence rates of carpal tunnel cases by case definition were 123.1/1, 000 in workers at washing department, 1117.2/1, 000 in workers at packing department, and 60.2/1, 000 in workers at yarning department. In male workers, the age-adjusted of cases were 355.9/1, 000 in workers at packing and delivery department, and 0.0/1, 000 in workers at other two departments. 6. The most of female workdrs at washing departmentn had the work history at packing department. 7. We concluded the carpal tunnel syndrome of female workers at packing department were work related.

• Tribology and Lubricants
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• 제22권1호
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• pp.20-25
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• 2006

The stress behavior analysis of a-rings and packing for a LPG filling unit has been presented using a finite element analysis technique by non-linear MSC/MARC program. The sealing performance and endurance of a-rings and packing are affected by working conditions such as filling pressure, friction coefficient, compression ratio, and material properties. The elastomeric polymers of O-rings and packing are nitrile butadiene rubber (NBR) and polytetrafluoroethylene (PTFE), which are selected as proper materials of a-rings and packing based on the stress analysis results. The calculated FEM results showed that the proper material of O-ring is NBR as a secondary sealing component and the recommended material of packing is PTFE as a primary sealing unit during a LPG filling process.

• 한국자원식물학회지
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• 제19권3호
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• pp.436-439
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• 2006

This study was carried out to obtain basic information for optimum storage method of leaf, stem and root of Angelica acutiloba Radix, which is being utilized as major cultivated herbal medicine materials, root of Angelica acutiloba was stored for 3 months in different packing materials and sealing methods, such as punched packing, sealing and vacuum packing. The results are summarized as follows. The loss in weight as influenced by packing materials and sealing degree was the lowest at vacuum packing and complete sealing condition with transparent polyethylene film. The ratio of root rot during the storage period was not significantly different between polyethylene films, but it was significantly different between sealing conditions. Therefore, vacuum packing and complete sealing with polyethylene film are desirable storage condition for Angelica acutiloba Radix.

• 한국세라믹학회지
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• 제31권1호
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• pp.31-38
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• 1994

To overcome the demerit of conventional forming method, new forming method, pressureless powder packing forming method, was investigated. This technique is performed by powder packing followed by the infiltration of binder solution. Various alumina powders were used as starting materials and the powders showing good packing condition through powder packing experiment were chosen. The green densities prepared by this new forming method with these powders were lower than those of specimens by pressing method, but, nearly same density was obtained in case of green body prepared with the powders having high packing density. The distribution of binder in a green body was homogeneous and it was possible to a complex shape form by this forming method.

• Archives of Plastic Surgery
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• 제38권5호
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• pp.602-608
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• 2011

Purpose: Nasal bone fracture is the most common type of facial bone fracture and most of nasal bone fracture is combined with septal fracture frequently. Nasal septum is important to support the distal nose and to maintain the nasal airway. But nasal septal fractures are usually unrecognized and untreated at the time of operation. Recently, various materials were using for nasal packing after closed reduction, however these materials are not focused on the correction of nasal bone and nasal septal fracture and many patients are suffered from nasal packing materials. Thus, the purpose of this study is to compare routine packing materials and rolled silastic sheet with respect to postoperative effect of correction of nasal bone fracture and discomfort of nasal packing materials. Methods: We examined 320 patients treated nasal bone fracture from January 2008 to December 2010. For Group I (n=92), $Merocel^{(R)}$ was used for nasal packing, for Group II (n=152) vaseline gauze was used, and Rolled silastic sheet (RSS) with vaseline gauze packing (VGP) was used for Group III (n=76). Under the general anesthesia, all patients were operated by closed reduction and nasal packing was done using three kinds of packing materials. At the time of postoperative 7 days, packing material was removed and studied for pt's satisfaction and postop. complications. Results: In patients with RSS with VGP, the complaints (nasal obstruction, foreign compressive sensation and discomfort during food ingestion) of keeping the nasal packing were decreased ($p$ <0.05) and the postoperative complication (deviation) were decreased comparing to vaseline gauze packing and $Merocel^{(R)}$ packing, however, these differences were not statistically significant ($p$ >0.05). Conclusion: Postoperative nasal packing with RSS with VGP was more comfortable to the patients and it was more effective method to correct the nasal bone fracture and nasal septal fracture.