• Elastomers and Composites
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• 제54권2호
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• pp.91-96
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• 2019

The purpose of this study was to examine the effect of different yarn twisting methods on physical properties. Plain single jersey structured fabrics were knitted from Kevlar yarn, and from Kevlar/HPPE, and from Kevlar/Basalt fiber, and from Kevlar/Glass fiber and Kevlar/Stainless steel fiber blended and core-spun yarns. and then, The fabrics were coated NBR Latex. The physical properties, including tear strength, modulus, degree of penetration, heat resistance, and cut resistance of the knitted fabrics were investigated and compared. Kevlar/HPPE blended yarn fabrics recorded the highest heat resistance (13 Sec.). and Kevlar/HPPE blended yarn fabrics had good cut resistance (Cut Level 4).

• 한국생산제조학회지
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• 제5권3호
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• pp.58-65
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• 1996

This thesis is concerned with the study on the characteristics of the cutting resistance occurring in finish machining of hardened steels such as carbon tool steel and alloy tool steel by a ceramic tool with nose radius. For the purpose, the shape of cutting cross-section made at nose part of the tool was analyzed geometrically and the wear mechanism on the flank face of the ceramic tool is investigated. In order to investigate the characteristics of cutting resistance two categories of cutting conditions are suggested, along with geometrical analysis. One category includes the conventional cutting parameters such as feed and depth of cut, another containing new cutting parameters of thickness of cut and width of cut etc. Thickness of cut width of cut and area of undeformed chip section formed by the condition of engagement between workpiece and cutting tool are determined as the function of feed, depth of cut and nose radius of cutting too, And an effective approach angle is determined by depth of cut and nose radius.

• 수산해양교육연구
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• 제26권4호
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• pp.831-837
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• 2014

This paper focuses on the effects of the changes in the resistance characteristics caused by the changes of the POD shape installed in the Hydrofoil vessel, using the CFD(Computational Fluid Dynamics). We input the POD sections' basic shape as the origin of the x and y axis. Then as we cut the x-axis 0 to 2 cm, and the more we cut it, the total resistance value had increased. However, we have recognized the fact that as we cut the POD section, 3 to 5 cm, the resistance value had rather decreased. Furthermore we found out the result that as the cut partition was larger; the POD cross-section would decrease, resulting in the linear decrease of the viscous force.

• 한국어병학회지
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• 제24권2호
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• pp.95-102
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• 2011

Normalized resistance interpretation (NRI) analysis for tetracycline was applied to generate information on the epidemiological cut-off value for Vibrio ichthyoenteri isolated from diseased olive flounder (Paralichthys olivaceus) larvae. Thus, 42 strains of V. ichthyoenteri were used to determine minimum inhibitory concentration (MIC) values of tetracycline using Etest. Also, 11 tetracycline resistance related genes were investigated by PCR method. Most tetracycline-resistant strains harbored both tetB and tetM with a few exceptions. NRI-derived mean and 2 SD above the mean of theoretical normal distributions of susceptible isolates were 0.33 mg/L and 1.66 mg/L, respectively. The epidemiological cut-off value for V. ichthyoenteri from the calculations could be set to S ${\leq}$ 2 mg/L. Of the 42 strains, 15 were classified as non-wild type (NWT), and MIC values of the NWT strains vary regardless of tetB and tetM detection, suggesting that there may be other mechanisms involved in tetracycline resistance in this Vibrio species.

• 한국염색가공학회지
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• 제14권4호
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• pp.223-228
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• 2002

Cotton fabric was treated with $TiO_2$-PEG600 dispersion colloid by pad-dry-cure and wet-fixation process to improve the performance properties as well as UV-cut effect. As the concentration of $TiO_2$/PEG increased tensile strength, crease resistance, stiffness of treated cotton fabric increased. Application of wet-fixation method provided a further improvement in tensile strength, crease resistance, stiffness of treated cotton fabric. Cotton fabric treated with $TiO_2$/PEG was more efficient in UV-cut property than untreated cotton.

• 소성∙가공
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• 제14권3호
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• pp.257-262
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• 2005

In order to improve the quality of the sheared surface in cutting of inner structure bonded sheet metal the cut-off operation is mainly investigated, which is the typical shearing process in sheet metal forming technology. The sandwich sheet metals considered have inner structure which is constructed in the form of crimped expanded metal and woven metal. The inner structure is bonded between solid sheet by resistance welding or adhesive bonding. The shearing process is visualized by the computer vision system installed in front of the cut-off die and the sheared surface is measured and quantitatively compared with the help of the optical microscope after cut-off operation. From test results we found that the influence of sheared position can be observed and explained clearly and this result can be utilized to get the better sheared surface.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 제3회 금형가공 심포지엄
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• pp.33-38
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• 2004

In order to improve the quality of the sheared surface in cutting of inner structure bonded sheet metal the cut-off operation is mainly investigated, which is the typical shearing process in sheet metal forming technology. The sandwich sheet metals considered have inner structure which is constructed in the form of crimped expanded metal and woven metal. The inner structure is bonded between solid sheet by resistance welding or adhesive bonding. The shearing process is visualized by the computer vision system installed in front of the cut-off die and the sheared surface is measured and quantitatively compared with the help of the optical microscope after cut-off operation. From test results we found that the influence of sheared position can be observed and explained clearly and this result can be utilized to get the better sheared surface.

• 한국식품과학회지
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• 제50권6호
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• pp.581-586
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• 2018

본 연구에서는 서울과 경기도 지역 소매점 및 대형마트에서 판매되고 있는 샐러드, 어린잎, 새싹채소로부터 Enterococcus의 존재를 파악하고 9개 항생제에 대한 항생제 저항성 프로파일을 확보했다. Quinupristin/dalfopristin에 저항성을 가지는 분리주가 85.0%에 이르렀고, 특히 E. faecalis 분리주는 18종 중 17종이 저항성을 나타냈다. 또한 critically important 항생제 중 highest priority로 분류되는 ciprofloxacin과 erythromycin에 대해 각각 40.0, 50.0%가 중간 정도의 저항성을 보였으며, vancomycin에 대한 저항성을 가지는 분리주는 검출되지 않았다. Enterococci의 항생제 저항성 정도는 식품 안전뿐만 아니라 공중 보건에 있어서도 중요하다는 측면에서 본 연구의 Enterococcus 오염 정도, 항생제 내성율에 대한 결과는 향후 신선 편이식품 섭취가 인체 건강에 미치는 위험분석을 위한 기초자료로서 유용한 정보를 제공할 것으로 보이며 앞으로 특별한 열처리 없이 섭취하는 신선 편이식품에 대한 지속적인 모니터링이 필요할 것이라 사료된다.

• 한국생산제조학회지
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• 제9권2호
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• pp.87-95
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• 2000

By using AIP(Arc Ion Plating) of a physical vapor deposition for the first time in Korea a ceramic tool whose surface is coated single layeredly with TiN is developed. In addition cutting resistance appearing in the process of finishing cut of hardened carbon tool steel STC3 is studied. The principal and radial components of cutting resistance in those cutting conditions appear to be the same or similar and the feed component is relatively small. The feed component is found to be in proportion to cutting width and the radial component in proportion to cutting thickness. Owing to coating the cutting resistance of a TiN coated ceramic tool increas-es compared with that of a general ceramic tool.

• Restorative Dentistry and Endodontics
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• 제6권1호
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• pp.115-122
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• 1980

The corrosion of silver amalgam is regarded as one of major causes in the failures of dental amalgam restorations. To evaluate the corrosion resistance of dental amalgam alloys, electrochemical tests such as potential and polarization measurement were used widely. But these commonly used methods have not provided the sufficient informations on relative resistance of amalgam to corrosion. In this experiment, the corrosion currents were measured using electronic potentiostat to compare some commercial dental amalgam alloys. All alloys were triturated in a amalgamator and condensed into a mold described in A.D.A. Specification No. 1 to produce cylinder form specimens of 4mm diameter by 5mm long. After specimen kept for 1 week at $37^{\circ}C$, each specimen was embedded in epoxy resin. The surfaces of specimens were then polished with a emery paper, diamond dust, and $Al_2O_3$. These specimens were immersed in artifical saliva kept at $37^{\circ}C$, and currents of each specimen were measured for 24 hours at 0.0volt (SCE). The author obtained conclusions as follows: 1. High copper amalgam showed superior resistance against corrosion to conventional amalgam, but a pellet form of high copper amalgam seemed to be susceptible to corrosion. 2. In lathe-cut alloys, fine-cut had superior resistance against corrosion to regular-cut. 3. Non-zinc conventional amalgam alloys were more resistant to corrosion than that of zinc containing conventional amalgam alloys. 4. In both of high copper and conventional amalgams, predispensed forms tended to have better resisitance to corrosion than that of pellet forms.