• 접착 및 계면
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• 제12권4호
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• pp.144-150
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• 2011

폴리스티렌을 저수축제로 사용하고 Zn-stearate를 이형제로 사용하여 함량변화에 따라 벌크 몰드컴파운드의 표면형태 및 기계적 물성에 미치는 영향을 고찰하였다. XPS, 접촉각 측정기 등을 이용하여 표면과 깊이 방향에 대한 원소함량과 접촉각을 측정하였고, 표면형태는 FESEM을 이용하여 관찰하였으며, 표면조도 측정은 AFM을 이용하였다. 저수축제를 첨가하지 않은 경우에 비교하여 저수축제를 9.0 wt% 첨가하였을 경우에는 체적수축률은 0.35%에서 0.05%로 감소하였으며, 표면조도는 $0.27{\mu}m$에서 $0.12{\mu}m$로 감소하였다. 이형제의 함량을 1.8 wt%에서 3.6 wt%로 증가시켰을 경우에는 이형제가 주로 표면에 존재하고 표면조도를 증가시키는 것을 확인하였다. 저수축제의 함량을 5.0 wt%에서 9.0 wt%로 증가시킴에 따라 굴곡탄성율과 충격강도가 약 30% 감소하였다.

• Tribology and Lubricants
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• 제18권5호
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• pp.345-350
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• 2002

Recently, as the development of manufacturing technique on SMC(sheet molding compound), various numerical and experimental approaches to injection and compression molding have been investigated. Injection and compression molding, however, has so various cases with complicated boundary condition that it is difficult to analyze mold characteristics precisely. In addition, since a slight change in process variables can significantly change the resulting mold thickness, a proper design is important to compression molding process. Therefore, in this study, the effects of various parameters on compression molding process have been investigated using FEM(finite element method) to formulate the melt front advancement during the mold filling process. To verify the results of present analysis, they are compared with those of reference. The results show a strong effect of initial charge volume, injection time and pressure as a result of variations in the rectangular charge shape.

• Archives of Pharmacal Research
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• 제8권3호
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• pp.149-157
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• 1985

The HCL hydrolyzate of the non-histone protein fractionated from the rat liver nuclei which have been incubated inthe presence of S-adenosyl-L-[methyl-$^{14}C$ ]-methionine shows at least four unidentified radioactive peaks on a basic amino acid analysis chromatogram. One of these unknown compounds (designated as compound 3) is also formed by the rat liver homogenated with the exogenous addition of an appropriate protein substrate. Since boiled rat liver homogenate or fresh homogenate in the absence of an exogenous protein substrate failed to form compound 3, its formation can be considered to be enzyme-catalyzed. The enzyme which yields compound 3 shows a preference of protein substrate in the order of reductively methylated hemoglobin > native > histone type II-A. The rat enzyme is nuclear in location associated with chromatin, and exhibits the highest activity in the liver among various rat organs. A compound 3-forming enzyme is also present in Neurospora crassa, since endogenous formation of the compound 3 can be demonstrated with the crude extract of this mold. The chemical identity of compound 3 is not yet known. However, it resisted to the following treatments; 6 N HCL and 0.1 N Na NaOH hydrolysis at $110^{\circ}C$, OR L-amino acid oxidase.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.301-302
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• 2007

• 한국기계가공학회지
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• 제18권6호
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• pp.76-81
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• 2019

In the mold-manufacturing field, various methods of advanced production technology are being used in the production of industrial-grade gear pulleys. Among the current methods are injection molding, hoop molding, insight molding, two-material molding, compound-mold molding, as well as engineering plastic mold. Currently, casting pulleys are inexpensive because they are produced in small quantities. However, they produce complications during the manufacturing process, are very unreasonable for mass production, and are disadvantageous in cost competitiveness. Pulleys are divided into hundreds of kinds and thousands of kinds, so the production methods vary. As these pulleys are made of a single material by a casting and welding method, they are not manufactured using injection molds consisting of different materials. In this research, pulleys, shafts, and reinforced plastic materials were incorporated using ANSYS software, and a low-cost, lightweight technology was applied for trial production with optimum design and extrusion technology.

• 한국정밀공학회지
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• 제17권2호
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• pp.73-79
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• 2000

The part-surface of mold or stamping-dies consists of a compound surface which consists of lots of composite surfaces, and may have various types of feature shapes including convex sharp edge (CSE). Those CSE features should be considered with care in machining the surface, which necessitates extraction of CSE curves on a compound surface. This work can be done rather easily for a solid model which has a complete topology information. In case of the compound surface without topology information, however, such CSE curves must be gathered through some geometrical calculations paying much computation time. In the paper, extracting CSE curves by the construction of a CSE region-map which can reduce time, and detecting various common edge types are presented.

• Asian-Australasian Journal of Animal Sciences
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• 제24권2호
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• pp.250-257
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• 2011

An experiment was conducted to determine the effects of different mycotoxin adsorbents including esterified glucomannan (EGM), hydrated sodium calcium aluminosilicate (HSCAS) and compound mycotoxin adsorbent (CMA) on performance, blood parameters, and liver pathological changes in broilers fed mold-contaminated feed. Two hundred and forty 10-day-old broilers were randomly assigned to one of the five dietary treatments including: i) control diet; ii) mold-contaminated diet; iii) moldcontaminated diet+0.05% EGM; iv) mold-contaminated diet+0.2% HSCAS; v) mold-contaminated diet+0.1% CMA. At 35-days-old, blood and liver tissue samples were collected for analysis. 0.1% CMA improved ADG and ADFI during 10-42 d compared to the moldcontaminated group (p<0.05). The mold-contaminated diet increased total white blood cell (WBC) number, haemoglobin (Hgb) concentration, hematocrit (Hct) level, serum aspartate aminotransferase (AST) and ${\gamma}$-glutamyl transferase (GGT) activities, and decreased red blood cell (RBC) number and serum globulin (GLB) and urea nitrogen (BUN) concentrations (p<0.05). The three mycotoxin adsorbents alleviated the alteration of RBC, WBC, Hgb and AST caused by the mold-contaminated diet. Furthermore, 0.1% CMA increased GLB concentration and decreased Hct level and GGT activity (p<0.05). Liver superoxide dismutase (SOD) activity was reduced, and myeloperoxidase (MPO) activity was increased by the mold-contaminated diet (p<0.05). Both EGM and HSCAS prevented the increase of MPO activity (p<0.05). Liver lesion, including severe vacuolar degeneration of hepatocytes, was observed in chicks fed the mold-contaminated diet. 0.05% EGM prevented these effects except for biliary hyperplasia and mild vacuolar degeneration. 0.2% HSCAS showed medium vacuolar degeneration of hepatocytes. Liver of broilers fed 0.1% CMA revealed a mild vacuolar degeneration. These results indicate that a mold-contaminated diet results in adverse effects on blood parameters and liver morphology. 0.05% EGM and 0.2% HSCAS partially alleviated the adverse effects. However, 0.1% CMA almost completely ameliorated the adverse effects.

• 대한기계학회논문집A
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• 제21권1호
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• pp.154-163
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• 1997

Thermally-induced deformation in SMC(Sheet Molding Compound) products is analyzed using three dimensional finite element method. Planar fiber orientation, which causes the anisotropic material properties, is calculated through the flow analysis during the compression stage of the mold. Also curing process is analyzed to predict temperature profile which has significant effects on warpage of SMC products. Through the developed procedure, effects of various process conditions such as charge location, mold temperature, fiber contents, and fiber orientations on deformation of final products are studied. and processing strategies are proposed to reduce the warpage and the shrinkage.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.581-586
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• 1996

This paper presents a feature recognition system for recognizing and extracting feature information needed for machining from design data contained in the CAD database of AutoCAD system. The developed system carries out feature recognition from an orthographic view of a press mold containing not only atomic features such as holes, pockets, and slots, but also compound features. Based on the result of feature recognition, it generates a 3-D modeling of the press mold. Especially, The feature recognition part is designed for detecting feature styles according to feature definition and classification, extracting parameters for various atomic features, and constructing necessary data structures for the recognized features.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 유기절연재료 방전 플라즈마
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• pp.23-28
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• 2000

Insulator systems using resin casting apparatus are useful to realize the high capacity, small size, and combined electric power equipments, and are expected to bring various advantages. In Korea, epoxy resin molded apparatus have been restricted to indoor uses till now. On the other hand, in Europe, molded insulators and transformers and so forth have been practically used since the former half of 1960's. Recently, investigation on epoxy resin materials and molded apparatus for outdoor use have ben intensively carried out. Probably, this is because electric power outdoor apparatus such as distribution transformer can be given multi-functions by using outdoor epoxy resin compound This study describes the trend on the development of epoxy mold transformers, and important technologies applied for outdoor use.