• Transactions of Materials Processing
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• v.10 no.6
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• pp.500-508
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• 2001

The integration of Rapid prototyping (RP) and Rapid Tooling (RT) has the potential for rapid net shaping of thee-dimensional parts, which have a geometrical complexity. In this study, a new R)P process, (VLM-SP), was proposed to manufacture net shapes of three-dimensional prototypes and it was shown that VLM-SP is an effective and economic process through the comparison of building time, building cost and dimensional accuracy for the test parts with the commercial RP processes ; LOM and FDM. In addition, the metal parts, which are a spanner shape and a clover punch, were produced by the plaster casting as one of RT using the prototypes of VLM-SP.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.42-45
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• 2003

The purpose of this study is the development or the extensive Rapid Prototyping Technique. which can resolve the long-term manufacturing process, shrinkage and deformation occurring rapid prototyping technique. To begin with. the various specimens for tensile were manufactured on the basis of this modeling technology. Then, many kinds of the laminate pieces for the test were made by using the sheet metals lmm and 1.5mm thickness which is composed of the same ingredient. The tensile specimen were manufactured by changing the process variables, Such as electric current, pressure and resistance welding time for the Rapid Prototyping with metal sheet. And then by using the Taguchi method. The interrelation between the specimen and mechanical properties were determined and the system for the optimum process variable organized.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.246-248
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• 1994

The Electrical properties of thin $SiO_2$ film by rapid thermal processing have been investigated and this film has been compared with thermal $SiO_2$ film by furnace. The RTO(rapid thermal oxide) film annealed in Ar ambient represent more superior properties than thermal $SiO_2$ film by furnace at breakdown field and leakage current. The RTO(rapid thermal oxide) film annealed in $NH_3$ ambient represent more inferior properties than thermal $SiO_2$ film by furnace at electrical properties, but the capacitance was improved 15-25% than the conventional oxide film.

• Journal of the Korean Society of Food Culture
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• v.15 no.2
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• pp.95-100
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• 2000

This study was attempt to improve the quality of rapid- and low salt-fermented liquefaction of sardine (Sardinops melanoslicta). Effect of pretreatment methods such as water adding, heating, and intermittent NaCl adding on fermented liquefaction of chopped whole sardine were investigated. The divisions of the experimental samples by pretreatment methods were as follows; Sample A (water adding and heating): chopped whole sardine adding 20% water and then adding 3 and 5% NaCl consecutively at the intervals of 3 and 6 hrs during heating for 9 hrs at $50^{\circ}C$ and then fermented at $33^{\circ}C$ for 90 days. Sample B (preheating): chopped whole sardine with 8% NaCl and heating at $50^{\circ}C$ for 9 hrs and then fermented at $33^{\circ}C$ for 90 days. Sample C (control): neither pretreatment methods of water adding nor preheating on chopped whole sardine with 13% NaCl and then fermented at $33^{\circ}C$ for 90 days. Comparison of the appropriate fermentation period, yield of hydrolysate, chemical composition of fermented liquefied products were carried out. The highest content of amino nitrogen appeared at 60 days in the sample A, 75 days in the sample B, and 90 days in the sample C during the fermentation period. The appropriate fermentation period of the sample A was shorten 15 days than the sample B and 30 days than the sample C in the processing of sardine. The product A was lower NaCl (8.5%) and lower histamine content (25mg/100g) than the sample B and C. Possibly, three kinds of pretreatment methods such as water adding, heating, and intermittent NaCl adding, might be recommend as the processing of rapid- and low salt-fermented liquefaction product of chopped whole sardine.

• Journal of the Korean Society of Food Culture
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• v.14 no.5
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• pp.455-460
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• 1999

In order to establish the processing condition of salt-fermented liquefaction of sardine (Sardinops melanoslicta), effect of temperature, pH value, and concentration of salinity on crude enzyme activity of sardine viscera were investigated. The optimum temperature range of crude enzyme activity in sardine viscera was $45{\sim}50^{\circ}C$ and the optimum pH value of it was 9.8. According to the concentration of salinity increased the crude enzyme activity in sardine viscera decreased. The relationship between concentration of salinity (X) and the crude enzyme activity (Y) in sardine viscera is shown as follows; Y=-0.01363X+0.7676 (r=-0.88). For the purpose of processing conditions of rapid- and low salt-fermented liquefaction of sardine, changes of viable cell count, histamine content, and volatile basic nitrogen (VBN) in the chopped whole sardine with 8% NaCl during preheating process at $40^{\circ},\;45^{\circ}$ and $50^{\circ}C$ for 48 hrs were analyzed. During preheating, initial viable cell counts of chopped whole sardine were $10^{4-7}/g$, but they decreased $10^{1-5}/g$ after 48 hrs. Histamine contents during preheating process at $40^{\circ}\;and\;45^{\circ}C$ were gradually increased, whereas at $50^{\circ}C$ were almost the same level after 48 hrs. VBN contents were continuously increased during preheating, but preheating at $50^{\circ}C$ samples were lower level than that of $40^{\circ}\;and\;45^{\circ}C$ ones. For the purpose to accelerate the fermentation and liquefaction of chopped whole sardine, preheating at optimum temperature of crude enzyme activity for 48 hrs was useful processing method and the contents of viable cell count, histamine, and VBN were safety level for food sanitation.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.2
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• pp.171-179
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• 2015

Recently, development of substitution aggregate is urgently needed because aggregate shortage is continuing due to the exhaustion of natural aggregate and strict restrictions of environment in construction industry. Therefore, In this study, new processing method to solve the problems of processing method of existing converter slag, namely, rapid cooling slag produced by the rapid cooling and crushing process of the high temperature melten slag into the rotary drum and then using the cooling water, compressed air and steel ball was examined fundamental properties for utilize as fine aggregate for concrete. In addition, through this study, we propose the utilization method of rapid cooling slag as fine aggregate for concrete.

• Transactions of Materials Processing
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• v.15 no.6 s.87
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• pp.436-440
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• 2006

A rapid tooling (RT) method fur the resin transfer molding (RTM) have been investigated. We fabricated a curved I-beam to verify the method. After creating a three-dimensional CAD model of the beam we fabricated a prototype of the model using a rapid prototyping (RP) machine. A soft mold was made using the prototype by the conventional silicone mold technique. The procedure and method of mold fabrication is described. The mold was cut into several parts to allow easier placement of the fiber preform. We conducted the resin transfer molding process and manufactured a composite beam with the mold. The preform was built by stacking up eight layers of delicately cut carbon fabrics. The fabrics were properly stitched to maintain the shape while placement. The manufactured composites beam was inspected and found well-impregnated. The fiber volume ratio of the fabricated beam was 16.85%.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.362-365
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• 2000

Rapid Prototyping(RP) techniques have revolutionized traditional manufacturing methods. These techniques allow the user to fabricate a part directly from a conceptual model before investing in production tooling and help develop new models with significant short time. This paper suggests to new process to manufacture large size hollow shape parts for prototype-car using Rapid Prototyping technology and Vacuum Molding with the reduction of delivery time. In addition, This paper introduces the dividing and combining method to make large size RP master model in spite of the limit of the build chamber dimensions of commercialized RP system and post-processing method to achieve sufficient surface quality.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.6
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• pp.99-105
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• 1997

Recently, with a great interest in micromachine, it is more and more important to promote the way of manufacturing micromachine. The silicon process or the LIGA process was the main method to manufacture micromachine in the past. But, these manufacturing method was 2.5-dimensinal, there was the limit in manufacturing perfect 3-dimensional structure micromachine. In this study, we developed the rapid prototyping system for micromachining and tested its property. We also realized .mu. m-order manu- facturing and 3-dimensional structure processing. The results showed the possibility of micromachining with the rapid prototyping system.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.3
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• pp.120-128
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• 2007

In order to reduce the lead-time and cost, the technology of rapid prototyping(RP) has been widely used. This paper describes the methodology to fabricate a large object by using the principle of rapid prototyping. By laminating thick and sloping polystyrene foam plates, we can make the large model which has three dimensional, continuous surfaces faster and easier than conventional processes. Estimated error was much smaller than other RP products which have stepped effect. For accuracy improvement and post processing, machined metal plates are added between the thick plates. To keep the continuity of surface and strengthen the model, pilot holes and guide rods are applied. By the methodology described in this paper, a missile body with flush air intake was fabricated.