Dongsik Kim
포항공과대학교 기계공학과 · 공학
다ongsik Kim 교수의 연구실은 레이저-물질 상호작용을 핵심으로 하여 고에너지 레이저를 활용한 첨단 제조 기술과 표면 정제 기술을 연구하고 있습니다. 특히 텅스텐과 같은 고융점 금속의 3D 프린팅 기술 개발과 함께, 액체 필름을 이용한 레이저 유도 표면 청소 및 나노접합 기술에 초점을 맞추고 있습니다. 이는 고정밀 및 저손실 가공을 가능하게 하여 반도체, 항공우주, 에너지 소자 등 첨단 산업에 응용될 수 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Although three-dimensional (3D) printing of tungsten parts by Powder Bed Fusion (PBF) has been demonstrated by multiple research groups, a directed energy deposition (DED) process for fabricating pure tungsten structures has never been reported. This work reports successful fabrication of pure tungsten structures by DED, revealing the required process conditions. The effect of laser power, scan speed, powder feed rate and carrier gas velocity on the stability and properties of the structures is
Femtosecond laser irradiation enables local crystalline nanojoining of silver nanowires with minimizing thermal damage on flexible substrates.
The effect of an artificially deposited liquid film on a laser-ablated metal surface at near-threshold laser fluences is presented. Experiments utilizing a Q-switched Nd:YAG laser (wavelength=1064 nm, full width at half maximum=6 ns) reveal that deposition of a liquid film results in substantial reduction of ablation threshold and enhancement of ablation yield. In addition, enlarged photoacoustic emission is detected in the ablation involving the liquid film. The augmentation of ablation efficie
The relay employs network coding to transmit the packets from the source nodes simultaneously, for increasing spectral efficiency in wireless environments. The cooperative transmission based on network coding usually works on decode-and-forward (DF) protocols. However, detection errors at the relay cause error propagation, which degrades the performance of cooperative communications. To overcome this problem, we model the error propagation effect of the DF-based system at the destination as the
