• 한국해양공학회지
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• 제19권3호
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• pp.54-58
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• 2005

Large-scale model tests of welded tubular K-joints were carried out to observe the fatigue behavior of API 2W Gr.50 steel produced by POSCO. The fatigue crack behaviors for various loading conditions were measured and investigated around the critical joint sections. The experimental results have been verified with numerical approaches and were also compared with the IIW, DnV RP-C203 and API RP 2A-WSD design curves. The hot-spot stress method was applied in the study. The SCF factor for tubular K-joint was also obtaine.

• 한국군사과학기술학회지
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• 제10권3호
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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.

• 한국식품저장유통학회지
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• 제19권3호
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• pp.337-343
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• 2012

시판 3사의 A, B 및 C 제품의 시판 딸기잼과 제조방법을 달리하여 직접 제조한 수제 딸기잼 즉 상압잼(HM-AP)과 감압잼(HM-RP) 등 5가지 딸기잼을 대상으로 총당, pH, 총산, 총 폴리페놀, 안토시아닌, 색도, 물성 및 관능검사를 실시하였다. 총당은 62.33~68.33 $^{\circ}Brix$이었고, pH는 3.59~3.78 범위였으며, 총산은 0.51~1.01으로 나타났다. 딸기잼의 색도 중 명도(L)은 11.02~14.80, 적색도(a)는 3.91~13.68로 상압잼이 유의적으로 높게 나타났다. 색소 성분인 총 폴리페놀 함량은 시판 잼 A, B, C의 경우 56.10, 97.59 및 105.85 mg GAE/100 g, 상압잼과 감압잼의 경우 각각 156.13, 189.94 mg GAE/100 g로 조사되었다. 안토시아닌 함량은 시판 잼 A, B, C의 경우 1.51, 0.95 및 0.80 mg/100 g, 상압잼과 감압잼의 경우 각각 2.64, 9.16 mg/100 g으로 나타났다. 감압잼은 총 폴리페놀과 안토시아닌 함량에 있어 다른 잼에 비해 유의적으로 높게 나타났다. 물성 중 경도는 $5.67{\times}10^3$ (HM-AP 잼)~$41.91{\times}10^3$ (B 잼) dyne/$cm^2$, 젤리강도는 40.08 (HM-AP 잼)~180.33 (B 잼) dyne, 파단응력은 83.84 (C 잼)~302.93 (B 잼) g 이었다. 관능검사로 색, 향, 단맛, 신맛, 발림성 및 종합적 기호도를 조사한 결과 HM-RP 잼이 다른 잼에 비해서 평점이 높은 것으로 나타났으며, 특히 색의 평점은 6.95로 가장 높은 것으로 나타났다. 항산화 활성을 나타내는 DPPH 라디칼소거능은 A, B, C, 상압잼 및 감압잼 각각 44.27, 41.70, 53.06, 69.08, 73.21% 였다. 본 결과는 저산소 가공기술을 이용하여 감압하에서 저온에서 제조한 HM-RP 딸기잼은 폴리페놀화합물의 산화 안정화로 총 폴리페놀과 안토시아닌 등 그 함량이 다른 잼에 비해 유의적으로 높은 것으로 사료된다.

• 한국정밀공학회지
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• 제19권2호
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• pp.95-105
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• 2002

In order to reduce the lead-time and cost, the technology of rapid prototyping (RP) has been widely used. However, RP technologies have disadvantageous characteristics according to their working principle: low building speed, high cost for introduction and maintenance of RP apparatus, stair-stepped surface and additional post processing. A new rapid prototyping process, as a transfer type of Variable Lamination Manufacturing by using expandable polystyrene room (VLM-ST), has been developed to reduce building lime. apparatus cost including the introduction and the maintenance and additional post-processing. The objective of this study is to propose a VLM-ST process and to develop an apparatus for implementation of the process. Design criteria of the apparatus are defined and the techniques arc proposed to satisfy the design criterion. In order to examine the efficiency and applicability of the developed process, various three-dimensional shapes, such as a world-cup logo. a knob shape, an extruded cross, a twisted shape, a character, Son-o-kong. a helical gear shaped and a scissor shape are fabricated on the apparatus in which unit shape layer (USL) was generated to build up each layer.

• 한국축산식품학회지
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• 제39권6호
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• pp.966-979
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• 2019

Muscle-based by-products are often undervalued although commonly reported having a high amount of natural bioactive peptides. In this study, elastin was isolated from the protein of broiler hen skin while its hydrolysate was prepared using Elastase. Assessment of antioxidative properties of elastin-based hydrolysate (EBH) was based on three different assays; 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical, 2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical and metal chelating ability. The EBH was purified further using ultrafiltration, gel filtration and Reverse- Phase High-Performance Liquid Chromatography (RP-HPLC). The IC₅₀ of ABTS radical activities for EBH were decreased as EBH further purified using ultrafiltration (EBH III; 0.66 mg/mL)>gel filtration (EB-II; 0.42 mg/mL)>RP-HPLC (EB-II4; 0.12 mg/mL). The sequential identification of the peptide was done by matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/ TOF-MS) of the potent fractions obtained from RP-HPLC (EB-II4). The presence of hydrophobic amino acids (Val and Pro) in the peptide sequences could potentially contribute to the high antioxidant activity of EBH. The sequences GAHTGPRKPFKPR, GMPGFDVR and ADASVLPK were identified as antioxidant peptides. In conclusion, the antioxidative potential from poultry skin specifically from elastin is evident and can be explored to be used in many applications such as health and pharmaceutical purposes.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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• pp.637-642
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• 2002

Generally, the use of robots in manufacturing industry has been increased during the past decade. GMA(Gas Metal Are) welding is an actively growing area and many new procedures have been developed for use with high strength alloys. One of the basic requirement for welding applications is to study relationships between process parameters and bead geometry. The objective of this paper is to develop a new approach involving the use of neural network and multiple regression methods in the prediction of bead geometry for GMA welding process and to develop an intelligent system that enables the prediction of bead geometry using Rapid Prototyping(RP) in order to employ the robotic GMA welding processes. This system developed using MATLAB/SIMULINK, could be effectively implemented not only for estimating bead geometry, but also employed to monitor and control the bead geometry in real time.

• 소성∙가공
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• 제10권6호
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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.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.217-222
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• 2006

Large-scale model tests of welded tubular K-joints were carried out to observe the fatigue behavior of API 2W Gr.60 steel produced by POSCO. The fatigue crack behaviors for various loading conditions were measured and investigated around the critical joint sections. The experimental results have been verified with numerical approaches and also compared with the IIW, DnV RP-C203 and API RP 2A-WSD design curves. The hot spot stress method was applied in the study. The SCF factor for tubular K-joint was also obtained.

• 한국군사과학기술학회지
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• 제7권2호
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• pp.88-99
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• 2004

A development of a software on radar target signature analysis is presented in this paper The target signature includes Radar Cross Section(RCS) prediction, Range Profile(RP) processing and Inverse Synthetic Aperture Radar(ISAR) processing. Physical Optics(PO) is the basic calculation method for RCS prediction and Geometrical Optics(GO) is used for ray tracing in the field calculation of multiple reflection. For RP and ISAR, Fast Fourier Transform(FFT) and Matrix Pencil(MP) method were implemented for post-processing. Those results are integrated into two separate softwares named as Radar Target Signature Generator(RTSG) and Radar Target Signature Analyser(RTSA). Several test results show good performances in radar signature prediction and analysis.

• 한국정밀공학회지
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• 제20권9호
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• pp.13-19
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• 2003