• 제목/요약/키워드: Engineering Plastics

검색결과 638건 처리시간 0.027초

드릴에 의한 유리섬유강화플라스틱의 절삭특성에 관한 연구 (A Study on the Cutting Characteristics of the Glass Fiber Reinforced Plastics by Drill Tools)

  • 박종남;조규재
    • 한국정밀공학회지
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    • 제21권3호
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    • pp.15-21
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    • 2004
  • Composite materials are widely used to make all kinds of machine parts, internal and structural materials of cars, aerospace industries, building structures, ship materials, sporting goods and others. It is worth the while to use composite materials as various substitutions when compared with others. But the use is limited in the field of the mechanical processing because of its difficulties in processing. Thus, it is proved that the surface is rough in and out of the hole processing the GFRP with HSS drill in the vertical machining center.

MCPs 압출 공법을 이용한 PP 수지의 고배율 압출 발포 연구 (A study for PP resin High magnification MCPs Extrusion foaming)

  • 현창훈;차성운;김학빈
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 추계학술대회 논문집
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    • pp.1046-1050
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    • 2005
  • Micro Cellular Plastics create a sensation at polymer industrial for lowering product cost & overcoming a lowering of mechanical intensity. There Is much development from injection molding pans but Extrusion parts is slow. This research is MCPs Extrusion parts, It is basis experiment for Process to make beads that is basis raw material of Package used most by shock mitigative of industry.

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통기성 세라믹형을 이용한 알루미늄 신발금형의 쾌속제작 (Rapid Tooling of Aluminum Shoes Mold Using Porous Mold)

  • 정성일;정두수;김도경;정해도;조규갑
    • 한국정밀공학회지
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    • 제16권11호
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    • pp.62-67
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    • 1999
  • The RP&M(Rapid Prototyping and Manufacturing) is the most appropriate technology for the small-lot production system, in which the production cycle is getting shorter owing to various needs from consumers. Recently RP products which are made of plastics, wax, and paper are used to verify the design of samples. But these products cannot be applied to the real mold because the strength enough to be a mold cannot be given by soft materials such as plastics. So RP products are copied to AFR(Al powder Filled Resin) molds or metal molds, which is called the RP&M. In this paper, RP&M is applied to a casting process. A porous casting mold, which is made from ceramic powder and binder, is used for rapid tooling of aluminum shoes molds.

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Municipal waste classification system design based on Faster-RCNN and YoloV4 mixed model

  • Liu, Gan;Lee, Sang-Hyun
    • International Journal of Advanced Culture Technology
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    • 제9권3호
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    • pp.305-314
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    • 2021
  • Currently, due to COVID-19, household waste has a lot of impact on the environment due to packaging of food delivery. In this paper, we design and implement Faster-RCNN, SSD, and YOLOv4 models for municipal waste detection and classification. The data set explores two types of plastics, which account for a large proportion of household waste, and the types of aluminum cans. To classify the plastic type and the aluminum can type, 1,083 aluminum can types and 1,003 plastic types were studied. In addition, in order to increase the accuracy, we compare and evaluate the loss value and the accuracy value for the detection of municipal waste classification using Faster-RCNN, SDD, and YoloV4 three models. As a final result of this paper, the average precision value of the SSD model is 99.99%, the average precision value of plastics is 97.65%, and the mAP value is 99.78%, which is the best result.

서로 다른 열환경에 노출된 고분자 소재의 열팽창계수 측정에 관한 연구 (A study on the Measurement of the Coefficient of Thermal Expansion of Polymer materials Exposed to Different Thermal Environments)

  • 김동주;박설현
    • 한국기계가공학회지
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    • 제20권4호
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    • pp.80-86
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    • 2021
  • Plastics are widely used in mechanical and other fields due to their light weight, design flexibility, and molding processability. In processing plastics, defective products are mixed and reprocessed to improve production efficiency and reduce costs. In this study, an experiment was conducted to confirm the coefficient of thermal expansion of HDPE during this reprocessing. The coefficient of thermal expansion was measured at different measurement directions and heating rates. As a result, we observed that the coefficient of thermal expansion in the direction perpendicular to the injection direction is greater than that in the horizontal direction.

Reinforced concrete corbels strengthened with carbon fiber reinforced plastics

  • Lu, Wen-Yao;Yu, Hsin-Wan;Chen, Chun-Liang;Yang, Tzong-Hwan;Lin, Yu-Sin
    • Computers and Concrete
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    • 제10권3호
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    • pp.259-276
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    • 2012
  • A total of nine reinforced concrete corbels were tested, in this study. Six were externally strengthened with carbon fiber reinforced plastics (CFRP), in the horizontal direction. The cross-sectional area of CFRP and the shear span-to-effective depth ratios are the parameters considered, in this study. Test results indicate that the higher the cross-sectional area of CFRP, the higher is the shear strength of the corbels, and the lower the shear span-to-effective depth ratios, the higher is the shear strength of corbels. The shear strength predicted by the design provisions in section 11.8 of the ACI Code, the strut-and-tie model in Appendix A of the ACI Code, and the softened strut-and-tie (SST) model were compared with the test results. The comparisons show that both the strut-and-tie model in Appendix A of the ACI Code, and the SST model can accurately predict the shear strength of reinforced concrete corbels, strengthened with CFRP.

다양한 화재조건에서 플라스틱 종류에 따른 연기입자의 크기분포 변화 측정 (Measurement of the Size Distribution of Smoke Particles with Plastic Types Under Various Fire Conditions)

  • 구재학;황철홍
    • 한국화재소방학회논문지
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    • 제31권6호
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    • pp.8-15
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    • 2017
  • 화재발생 시에 대부분의 인명 피해는 연기에 의해 발생되는데, 최근 건축 내장재에서 차지하는 플라스틱의 양이 많아지며 발생되는 연기의 유독성이 점차적으로 증가되고 있다. 연기에 의한 인체피해의 상당부분은 흡입연기의 폐침전과 관련이 있으며, 연기입자의 크기분포는 폐침전 특성에 직접적인 영향을 미친다. 따라서 플라스틱 종류에 따른 연기입자의 크기별 발생량 검토는 폐침전에 의한 인체피해 연구에 필수적으로 요구된다. 최근의 목재와 폴리프로필렌(PP)에 대한 연기입자의 발생특성 연구에서 PP의 연기입자 크기분포 특성이 몇 가지 측면에서 목재와는 확연히 다르게 나타났다. 이에 따라, 본 연구에서는 다른 플라스틱들도 연기입자 크기분포에서 PP와 같은 특성을 보이는지 알아보기 위해서 대표적인 4가지 플라스틱(LDPE, PA66, PMMA, PVC)에 대하여 연기입자 크기분포 측정실험을 수행하였다. 특정 조건에서 연소생성물을 균일하게 생성하고 분석하기 위하여 ISO/TS 19700 기준에 따른 등속튜브연소로를 이용하여 연소로의 온도와 산소공급량에 따라 다양한 화재조건에서 연기입자를 균일하게 발생시키고, 정전저압 임팩터를 사용하여 연기입자의 크기에 따른 개수농도를 실시간으로 측정하였다. 실험 결과 4가지 플라스틱의 연기입자 크기분포 특성은 여러 측면에서 PP와 유사하며 목재와는 확연히 다르게 나타났다.