• 월간포장계
• /
• 통권201호
• /
• pp.82-88
• /
• 2010

• 대한의용생체공학회:의공학회지
• /
• 제40권2호
• /
• pp.55-61
• /
• 2019

Recently, various researches on materials and equipment have been actively conducted to overcome the limitations of conventional output methods due to the increase of diversity of 3D printing materials and to adopt an output method suitable for the characteristics of each material. As the range applicable to outputable materials is expanded, manufacturing of medical devices applied to patients is in a more rapid growth trend than other fields. In this study, we investigated the suitable materials for fabricating 3D printer using photocurable resin. As a result, one suitable material was selected through biological safety experiment and thermal stability experiment. Next, to optimize the output of the selected materials, we have developed a system that optimizes the equipment according to the characteristics of the material. The results of this study enabled the implementation of personalized medical implants that could not be made from 3D printer dependent materials, thereby overcoming the limitations of existing 3D printer output conditions and dedicated materials.

• 한국정보통신학회논문지
• /
• 제23권12호
• /
• pp.1742-1745
• /
• 2019

Hidden flame detection after allegedly extinguishing a fire cannot be emphasized enough. There are a few commercial hidden fire detection equipments which are imported, but the cost is relatively high. In this contribution, we propose a development of a low-cost, high-performance hidden flame detector using open-source hardware/software. We use Raspberry-pi based hardware board equipped with a TFT touch-screen LCD, a 3G modem, and an attachable battery device altogether integrated in a plastic case fabricated with a 3D printer. The proposed hidden flame detector shows the same performance of a commercial product FLIR E5 while consuming less than a half of the cost.

• 전자공학회논문지S
• /
• 제34S권5호
• /
• pp.73-85
• /
• 1997

In a drop-on-demand thermal ink-jet printer, the dot size of an ink droplet expelled from a printer depends on the absorption of the paper. This causes severe differences between output images on the different paper materials. In this paper, the color matching algorithm for different papers is proposed. To achieve corresponding color reproduction, dot gain compensatio nbased on saturation was applied to predict color reproduction on a printer. If the dot gain of pigment increases, the white portion of paper decreases while the saturation value increases monotonically. As the results of dot gain compensation, intensity change may appear. Therefore, an intensity compensation without any hue variation is followed to match the colors of different subtrates.

• 한국정밀공학회지
• /
• 제15권9호
• /
• pp.50-55
• /
• 1998

A thermal printing head is used for heat transcription printing of facsimile or printer. The thermal printing head has multilayered thin films and heaters lined up. Thermal analysis of thermal printing head is important for a design of thermal printing head. Since the heating charateristics of thermal printing head is dependent on the thermal conductivities of multilayerd material, this study made numerical analysis for three dimensional transient heat conduction in mutilayered films by the finite difference method and investigated the effect of various thermal conductivities of thin films. The results of this study will be used to design thermal printing head and select the materials for thermal printing head.

• Elastomers and Composites
• /
• 제51권4호
• /
• pp.301-307
• /
• 2016

Additive manufacturing (AM), so called 3D Printing is a new manufacturing process and is getting attraction from many industries. There are several methods of 3D printing. Among them fused deposition modeling (FDM) type is most widely used by reason of cheap maintenance, easy operation and variety of polymeric materials. Articles manufactured by 3D printing have weak deposition strength compared with conventionally manufactured products. Deposition strength of FDM type 3D printed article is highly dependent of deposition temperature. Subsequently the nozzle temperature in the FDM type 3D printing is very important and it is controlled by heat source in the 3D printer. Nozzle is connected with heat block and barrel, and heat block contains heat source. Nozzle becomes hot through heat conduction from heat source. Nozzle temperature has been predicted for various thermal boundary conditions by computer simulation and compared with experimental measurement. Nozzle temperature highly depends upon thermal conductivities of heat block and nozzle. Simulation results are good agreement with experiment.

• 대한의용생체공학회:학술대회논문집
• /
• 대한의용생체공학회 1997년도 춘계학술대회
• /
• pp.338-341
• /
• 1997

The current consumption and the heat produced in the printhead of thermal printer are mainly governed by total printing dots and printing time for each line. Simple algorithm is proposed to optimize the performance of a thermal printhead, which use variable division according to bit-mapped data of its 1 line. And, for protecting the thermal printhead from exceeding heat, I control the heat energy of each microheater(dots) on the thermal printhead through changes in the applied pulse width.

• 한국산학기술학회논문지
• /
• 제11권10호
• /
• pp.3893-3897
• /
• 2010

LBP 현상기 롤러는 시간이 지나면 자기력과 자화 특성이 감소하게 되며 이런 자성체 감소로 인해 인쇄 품질이 떨어진다. 본 연구에서는 재활용에 따른 현상기 롤러의 자성 분포를 조사하여 신제품과 비교함으로써 재활용의 사용 가능성 및 자성체의 경시 변화에 대해 제한하였다.

• 한국산업융합학회 논문집
• /
• 제26권6_1호
• /
• pp.977-983
• /
• 2023

The tank uses a twin turbo diesel engine equipped with two turbocharger systems for high output. The main component of the turbocharger system is the turbine housing through which the exhaust flows. Turbine housing is manufactured through a sand casting process, taking into account the shape and material characteristics according to the environmental conditions in which it is used. Currently, turbine housing is imported, and local production is necessary. In this study, basic research was conducted to localize the turbine housing of a tank diesel turbo engine. Reverse engineering and finite element analysis of the imported turbine housing were performed. The prototype of the turbine housing was printed using FDM and PBF 3D printers. The prototype of the turbine housing printed with an FDM 3D printer has an overall appearance similar to 3D modeling, but the printed surface of the whorl part is rough. The prototype printed with the PBF 3D printer is completely identical to the 3D modeling, including the whorl part.

• Elastomers and Composites
• /
• 제52권3호
• /
• pp.216-223
• /
• 2017

The additive manufacturing technology, also called 3D printing, is growing fast. There are several methods for 3D printing. Fused deposition modeling (FDM) type 3D printing is the most popular method because it is simple and inexpensive. Moreover, it can be used for printing various thermoplastic materials. However, it contains the cooling of layered road and causes thermal shrinkage. Thermal shrinkage should be controlled to obtain high-quality products. In this study, temperature distribution and cooling behavior of a layered road with cooling are studied through computer simulation. The thermal shrinkage of the layered road was simulated using the calculated temperature distribution with time. Shape variation of the layered road was predicted as cooling proceeded. Stress between the bed and the layered road was also predicted.This stress was considered as the detaching stress of the layered road from the bed. The simulations were performed for various thermal conductivities and temperatures of the layered road, bed temperature, and chamber temperature of a 3D printer. The simulation results provide detailed information about the layered road for FDM type 3D printing under operational conditions.