Earticle

Recently 3d printer industry has two demands. first is color 3d printing. second is mass production using 3d printer that has large bed. According to previous studies, 3D printed objects have different weights depending on filament colors. 3D printed tensile specimens with filaments of various colors were checked to see they had the same weight. If so, we wanted to see it was statistically significant. As a result, we found that the weight of 3D printed objects was statistically significantly different depending on the filament color. The average weight of 3d printed objects is: Black(8.63g), Blue(8.58g), Yellow(8.53g), White(8.48g), Natural(8.46g), Green (8.45g), Red(8.42g).

Fused Deposition Modeling (FDM), also known as Fused Deposition Modeling (FFF), is the most widely used type of 3D printing at the consumer level. The FDM 3D printer extracts thermoplastic filaments such as ABS (Acrylonitrile Butadiene Styrene) and Polyactive Acid (PLA) through heated nozzles to dissolve the material. It works by applying layers of plastic to build platforms. Various demands for 3D printers increased, and among these demands, there was also a demand for various filament colors. ABS, one of the main filamentous materials for 3D printers, is easy to color in a variety of colors and has been studied to meet the needs of these users. Through quantitative measurements in this work, we confirm that color differences remain depending on the difference in placement on the 3D printer bad. In addition, the temperature of the specimen was measured at the start of 3D printing, during manufacturing, and at the completion of manufacturing, and the inner and central sides remained similar, but the outer sides were 5 degrees lower. These temperature differences accumulate as layers pile up, resulting in differences in weight or color, which in turn meet consumer and producer needs in the 3D printer industry.

This thesis develops a fuzzy-PID control algorithm for control the filament winding tension. It is developed by applying classical PID control technique to a fuzzy logic controller. It is composed of a fuzzy-PI controller and a fuzzy-D controller. The fuzzy-PI controller uses error and integrated error as inputs, and the fuzzy-D controller uses derivative of error as input. The fuzzy-PI controller uses Takagi-Sugeno fuzzy inference system, and the fuzzy-D controller uses Mamdani fuzzy inference system. The fuzzy rule base for the fuzzy-PI controller is designed using 19 rules, and the fuzzy rule base for the fuzzy-D controller is designed using 5 rules. A test-bed is set-up for verifying the effectiveness of the developing control algorithm in control the filament winding tension. It is composed of a mandrel, a carriage, a force sensor, a driving roller, nip rollers, a creel, and a real-time control system. Nip rollers apply a vertical force to a filament, and the driving roller drives it. The real-time control system is developed by using MATLAB/xPC Target. First, experiments for showing the inherent problems of an open-loop control scheme in a filament winding are performed. Then, experiments for showing the robustness of the developing fuzzy-PID control algorithm are performed under various working conditions occurring in a filament winding such as mandrel rotating speed change, carriage traversing, spool radius change, and reference input change.

Most of agricultural structures are consisted of complex components and exposed to various boundary conditions. There have been no ways to express those structures exactly for model experiment. As an alternative, 3D printer can produce any type of solid model. However, there are limited informations related to structural experiments using 3D printer. The object of this study gives the basic informations to structural engineers who try to use 3D printer for model experiment. When PLA was used as a supplier for 3D printer, the outcomes showed less heat deformation to compare with ABS. To test the material properties, two kinds of experiments (three-point flexibility test and compression test) were executed using universal testing machine. In three-point flexibility test, plastic hinge and its deformation were developed as observed in material such as steel. The behavior was in a linear elastic state, and elastic bending modulus and yield force were evaluated. In the compression test using unbraced columns with hinge-hinge boundary condition, the constant yield forces were observed regardless of different lengths in all columns with same section size, whereas the compressive elastic modulus was increased as the length of column was increased. The suggested results can be used for model experiments of various agricultural structures consisted of single material.

화순 폐광산에서 생성되는 광산배수와 황갈색 철수산화물에 대한 지구화학적 특징을 조사하였다. 항도로부터 배출되는 광산배수의 pH는 7.19에서 8.03으로 변화하였고, 광산배수에 용해되어 있는 Fe 이온은 0.048mg/l에서 1.6 mg/l로 나타났다. 그리고 광산배수로부터 형성된 황갈색 철수산화물에는 Fe2O3 함량이 22.87 wt.%에서 55.07 wt.%로 나타났다. 광산배수에는 As 이온 함량이 76.94 ㎍/l에서 167.9 ㎍/l로 용해되어 있고 황갈색철수산화물에 As 함량이 8400～21300 mg/kg으로 매우 높게 나타났다. 광산배수 중에 용해되어 있는 As 이온이황갈색 철수산화물에 흡착 및 공침전으로 흡착된 것으로 사료된다. 이 비정질의 철수산화물은 광산배수에 용해되어 있는 As 이온은 물론 중금속이온도 제거할 수 있는 흡착제로 사용될 수 있을 것으로 사료된다. 비정질철수산화물에서 협막 구조물과 나선형-구조물이 관찰되었다. 이들 구조는 철수산화물을 생성하는 미생물체로사료되며, 협막 구조물과 나선형구조물에 부착된 철수산화물에서 Fe와 As가 EDS분석에서 검출되었다. 협막및 나선형 구조물이 미생물 기원임을 확인하기 위하여 광산배수와 철수산화물의 혼합물을 펩톤과 FeSO4･7H2O 가 포함된 배양용액에서 배양하였다. 협막 구조물과 나선형의 구조물이 배양용액에서 뚜렷하게 관찰되었다.

Thin-film shape technology is recognized for its core technology to enhance the technology of LCD, PDP, semiconductor manufacturing processes, hard disks and optical disks, and is widely used to form coated thin films of products. In addition, resistance (electron beam filament) technology for heating is used to manufacture filament for ion implants used in semiconductor manufacturing processes. By establishing an electronic beam filament production system and developing seven specifications of electronic beam filament, it is contributing to improving trade dynamics and increasing exports to Japan through localized media of theoretical imports to domestic companies. In this study, CAE analysis was performed after setting electron beam filament specification and development objectives, facilities and fabrication for electron beam filament production, electron beam filament JIG & fixture design and fabrication followed by electron beam filament prototype. Then, the automation and complete inspection equipment of the previously developed electronic beam filament manufacturing facilities was developed and researched to mass-produce them, to analyze and modify prototypes, design and manufacture automation facilities, and finally, to design and manufacture the complete inspection equipment. In this paper, design and manufacture of electronic beam filament total inspection equipment for mass production were dealted with.

Thin-film shape technology is recognized for its core technology to enhance the technology of LCD, PDP, semiconductor manufacturing processes, hard disks and optical disks, and is widely used to form coated thin films of products. In addition, resistance (electron beam filament) technology for heating is used to manufacture filament for ion implants used in semiconductor manufacturing processes. By establishing an electronic beam filament production system and developing seven specifications of electronic beam filament, it is contributing to improving trade dynamics and increasing exports to Japan through localized media of theoretical imports to domestic companies. In this study, CAE analysis was performed after setting electron beam filament specification and development objectives, facilities and fabrication for electron beam filament production, electron beam filament JIG & fixture design and fabrication followed by electron beam filament prototype. Then, the automation and complete inspection equipment of the previously developed electronic beam filament manufacturing facilities was developed and researched to mass-produce them, to analyze and modify prototypes, design and manufacture automation facilities, and finally, to design and manufacture the complete inspection equipment. In this paper, analysis and modification of prototypes of electron beam filaments for mass production were dealted with.

Thin-film shape technology is recognized for its core technology to enhance the technology of LCD, PDP, semiconductor manufacturing processes, hard disks and optical disks, and is widely used to form coated thin films of products. In addition, resistance (electron beam filament) technology for heating is used to manufacture filament for ion implants used in semiconductor manufacturing processes. By establishing an electronic beam filament production system and developing seven specifications of electronic beam filament, it is contributing to improving trade dynamics and increasing exports to Japan through localized media of theoretical imports to domestic companies. In this study, CAE analysis was performed after setting electron beam filament specification and development objectives, facilities and fabrication for electron beam filament production, electron beam filament JIG & fixture design and fabrication followed by electron beam filament prototype. Then, the automation and complete inspection equipment of the previously developed electronic beam filament manufacturing facilities was developed and researched to mass-produce them, to analyze and modify prototypes, design and manufacture automation facilities, and finally, to design and manufacture the complete inspection equipment. In this paper, design and manufacture of electronic beam filament automation facilities for mass production were dealted with.

Thin-film shape technology is recognized for its core technology to enhance the technology of LCD, PDP, semiconductor manufacturing processes, hard disks and optical disks, and is widely used to form coated thin films of products. In addition, resistance (electron beam filament) technology for heating is used to manufacture filament for ion implants used in semiconductor manufacturing processes. By establishing an electronic beam filament production system and developing seven specifications of electronic beam filament, it is contributing to improving trade dynamics and increasing exports to Japan through localized media of theoretical imports to domestic companies. In this study, CAE analysis was performed after setting electron beam filament specification and development objectives, facilities and fabrication for electron beam filament production, electron beam filament JIG & fixture design and fabrication followed by electron beam filament prototype. Then, the automation and complete inspection equipment of the previously developed electronic beam filament manufacturing facilities was developed and researched to mass-produce them, to analyze and modify prototypes, design and manufacture automation facilities, and finally, to design and manufacture the complete inspection equipment. In this paper, mainly jig & fixture design, production and trial production of electron beam filament were dealted with.

Thin-film shape technology is recognized for its core technology to enhance the technology of LCD, PDP, semiconductor manufacturing processes, hard disks and optical disks, and is widely used to form coated thin films of products. In addition, resistance (electron beam filament) technology for heating is used to manufacture filament for ion implants used in semiconductor manufacturing processes. By establishing an electronic beam filament production system and developing seven specifications of electronic beam filament, it is contributing to improving trade dynamics and increasing exports to Japan through localized media of theoretical imports to domestic companies. In this study, CAE analysis was performed after setting electron beam filament specification and development objectives, facilities and fabrication for electron beam filament production, electron beam filament JIG & fixture design and fabrication followed by electron beam filament prototype. Then, the automation and complete inspection equipment of the previously developed electronic beam filament manufacturing facilities was developed and researched to mass-produce them, to analyze and modify prototypes, design and manufacture automation facilities, and finally, to design and manufacture the complete inspection equipment. In this paper, mainly design and manufacturing of facilities for making electron beam filament were dealted with.

Thin-film shape technology is recognized for its core technology to enhance the technology of LCD, PDP, semiconductor manufacturing processes, hard disks and optical disks, and is widely used to form coated thin films of products. In addition, resistance(electron beam filament) technology for heating is used to manufacture filament for ion implants used in semiconductor manufacturing processes. By establishing an electronic beam filament production system and developing seven specifications of electronic beam filament, it is contributing to improving trade dynamics and increasing exports to Japan through localized media of theoretical imports to domestic companies. In this study, CAE analysis was performed after setting electron beam filament specification and development objectives, facilities and fabrication for electron beam filament production, electron beam filament JIG & fixture design and fabrication followed by electron beam filament prototype. Then, the automation and complete inspection equipment of the previously developed electronic beam filament manufacturing facilities was developed and researched to mass-produce them, to analyze and modify prototypes, design and manufacture automation facilities, and finally, to design and manufacture the complete inspection equipment. In this paper, mainly electron beam filament specification analysis and development objectives and CAE analysis were dealted with.

Sampling biological evidence is one of the most critical step in forensic DNA typing. Touch DNA samples were known to be difficult to analyse compared to bloodstain, semen stain and saliva stains. In this study, nano filament fiber was evaluated as a tool for collecting trace DNA samples by comparing other commercial swabs such as cotton swab, cotton gauze, flocked swab, isohelix swab. Diluted blood stains were prepared on porous and non-porous materials such as wood and glass plate, respectively. DNA quantity was analyzed by qPCR and compared. Nano filament fiber showed higher concentration of DNA compared to other tools such as cotton swab. This study showed the feasibility of nano filament fiber as a novel tool for trace DNA analysis.

Since electric energy is used in industry, mass production and various conveniences are provided. To provide convenience for the construction and operation of such electric energy transmission and distribution facilities, it is increasing that the demand for special purpose vehicles, that is, telescopic aerial work platform vehicles. When working active electric work using the telescopic aerial work platform vehicles, due to active electric work is inevitable, it is essential to ensure insulation performance for the safety of the operator. In this paper, we study the design and development of mechanical properties for filament winding process of glassfiber/epoxy composite, it is required to boom of telescopic aerial work platform vehicles. The glass fiber/epoxy composite filament winding process and its mechanical properties were evaluated to replace the existing ATOS80 boom. By filament winding process it was obtained the mechanical properties required for the design analysis of the glass fiber/epoxy composite boom. Using this, the insulated boom for the 30m class aerial work vehicle was designed and was manufactured by applying the filament winding process. The fabricated composite boom was evaluated by the static strength test to meet the required strength. The maximum displacement was 84mm and the crack occurred at the maximum load of 8981N. It satisfied the maximum lifting load of 4900N and 210mm the maximum displacement required for the boom.

Due to rapid industrialization and urbanization, maintenance of high voltage transmission lines in narrow alleys, complex roads, or old factory areas is required. Since the existing aerial lift vehicle is made of steel, there is a risk of electric shock. Therefore, there is a need for the development of an insulated aerial lift vehicle that can prevent electric shock accidents during electrical work. In particular, the development of an insulated aerial lift vehicle is required in a recent work environment where live line work is inevitable. The development of composite insulation boom for the vertical swing type aerial lift vehicle is studied. The insulated boom was developed by applying glass fiber-epoxy composite and filament winding process. The developed insulated boom was verified by measuring dielectric breakdown strength, surface resistance and volume resistance according to ASTM D149 and ASTM D257.

In this paper, quasi-static crushing tests of composite circular tubes under axial compression load are conducted to investigate the energy absorption characteristics. Circular tubes used for this experiment are glass/epoxy (GFRP) composite tubes, which is fabricated by the filament winding method. One edge of the composite tube is chamfered to reduce the initial peak load and to prevent catastrophic failure during crushing process. Two suggested trigger mechanisms for the composite tubes are investigated. Crushing modes are mainly affected by thickness/diameter ratio, and average crushing loads are mainly affected by their cross-sections. Energy absorption characteristics vary significantly as a function of the tube geometry, trigger mechanism, t/D ratio and the cross-sectional shape.

Filament Winding Process is a comparatively simple operation in which continuous reinforcements in the form of roving are wound over a rotating mandrel. And now well established as a versatile method for storage tanks and pipe for the chemical and other industries . In this study, tensile strength of a filament wound ring specimens were evaluated by split disk test fixture and dress disk test fixture , The results obtained from experiments were compared with the theoretical values obtained by the rule of mixtures. And the purpose of this paper is the suggestion of an appropriate test method for the evaluation of tensile properties of filament wound structures .The tensile strength of a ring specimen tested by the dress disk test showed better agreement with the theoretical values than of a ring specimen tested by the split disk test because the stress concentration in edges of a split disk test fixture is more severe than that of dress disk test fixture. The results showed that the tensile strength of a ring specimen was influenced by the geometry of test fixture, the continuity of fibers, fiber-tension, fiber-end and stress concentration in specimen.

헬기 로터깃은 최초로 항공기의 일차구조물로 사용된 대형 복합재료구조물이다. 헬기 로터깃은 운용기간(service life)동안에 $10^{7}$이나 $10^{8}$의 high-cycle 피로환경을 경험가게 된다. 로터깃은 복합재료가 알맞게만 사용된다면 거의 무한대의 피로수명을 갖게된다고 알려져 있다.

Hot filament 플라즈마 화학기상 증착법(HFPECVD)를 사용하여 질산화철의 농도에 따른 탄소나노튜브의 성장 특성을 관찰하기 위해 실험을 진행하였다. 암모니아($NH_3$)를 희석가스로 사용하였고, 아세틸렌($C_2H_2$)를 탄소 원료가스로 각각 사용하였다. 암모니아 가스 플라즈마를 사용하여 전처리 된 질산화철 촉매층의 SEM(Scanning Electron Microscopy) 이미지를 관찰하여 본 결과, 나노 사이즈의 촉매 그레인(grain)을 발견할 수 있었다. 그리고 탄소 나노튜브의 직경과 성장 밀도 또한 전처리 된 촉매 층에 따라 다른 양상을 보였다. TEM(Transmission Electron Microscopy)를 사용하여 탄소나노튜브를 관찰한 결과 bamboo 구조를 한 다중벽 탄소 나노튜브(MWCNT)를 관찰할 수 있었다.