基于PenTile RGBWTM算法的高像素密度a-Si TFT移动液晶显示屏

采用传统的移动设备设计规则,基于PenTile RGBWTM算法开发了a-Si TFT移动液晶显示屏。将AFFS模式和PenTile RGBWTM算法相结合,制作的TFT液晶屏获得了超过200 cd/ m2的高亮度,500∶1的高对比度,以及达到VGA标准,可以清晰显示互联网网页的高分辨率。     

Design and Synthesis of CdHgSe/HgS/CdZnS Core/Multi-Shell Quantum Dots Exhibiting High-Quantum-Yield Tissue-Penetrating Shortwave Infrared Luminescence

Cd_xHg_1−xSe/HgS/Cd_yZn_1−yS core/multi-shell quantum dots (QDs) exhibiting bright tissue-penetrating shortwave infrared (SWIR; 1000–1700 nm) photoluminescence (PL) are engineered. The new structure consists of a quasi-type-II Cd_xHg_1−xSe/HgS core/inner shell domain creating luminescent bandgap tunable across SWIR window and a wide-bandgap Cd_yZn_1−yS outer shell boosting the PL quantum yield (QY). This compositional sequence also facilitates uniform and coherent shell growth by minimizing interfacial lattice mismatches, resulting in high QYs in both organic (40–80%) and aqueous (20–70%) solvents with maximum QYs of 87 and 73%, respectively, which are comparable to those of brightest visible-to-near infrared QDs. Moreover, they maintain bright PL in a photocurable resin (QY 40%, peak wavelength ≈ 1300 nm), enabling the fabrication of SWIR-luminescent composites of diverse morphology and concentration. These composites are used to localize controlled amounts of SWIR QDs inside artificial (Intralipid) and porcine tissues and quantitatively evaluate the applicability as luminescent probes for deep-tissue imaging.     

The effect of a hot-wire in the tandem GMAW process ascertained by developing a multiphysics simulation model

Journal of Mechanical Science and Technology - Physical phenomena such as arc interference, deflection in droplet transfer, and bulging in weld pool are observed in the tandem gas metal arc welding...     

A review of magnetic actuation systems and magnetically actuated guidewire- and catheter-based microrobots for vascular interventions

Magnetic actuation techniques and microrobots have attracted considerable interest due to their potential applications in biomedicine. Interventional techniques have emerged as a minimally invasive approach to treat a wide range of vascular diseases. The current practice of interventional procedures is, however, limited by manual control of interventional devices and time-consuming procedures. Moreover, fluoroscopy is considered as an essential part of the procedure today despite posing many limitations for patients and physicians. Recently, various microrobotic solutions have been proposed for vascular interventions, including advances in magnetic navigation systems and magnetically steerable catheters and guidewires, which have shown potential benefits such as reduced radiation doses, improved access to difficult-to-reach and tortuous anatomy. This paper reviews the commercial magnetic actuation systems and magnetically actuated interventional microrobots that have been developed by academic research groups and medical companies worldwide, outlining their capability, applicability as well as limitations. We further address the challenges and future prospects of the research toward clinical acceptance of magnetic interventional technologies.

     

Photochemical heterogeneous catalytic reaction at recirculated reactor system

A study was undertaken to examine the possibility of combining a batch-recirculated photoreactor with a ceramic membrane filter for heterogeneous photocatalysis applications. D-cargo red GS (GS) was used as the test substrate and titanium dioxide was used as photocatalyst for this study. The dark adsorption of GS on the TiO₂ particle surface was also analyzed. The adsorption trends of GS at various initial concentrations followed the Langmuir isotherm trend. The GS were decolorized from 20% to 70% by the dark adsorption with various concentrations. The photodegradation of GS after the dark adsorption showed the behavior of Langmuir-Hinshelwood model. The variation of recirculation flow rate did not much influence photocatalysis. Variation tendencies of GS concentration were almost similar after about 90 minutes illumination in spite of the flow rate change. The values ofk (apparent first order rate constant) also varied with increase of the recirculation flow rate, but there were no observable significant differences between them. Presented at the Int’l Symp. on Chem. Eng. (Cheju, Feb. 8–10, 2001), dedicated to Prof. H. S. Chun on the occasion of his retirement from Korea University.     

Thyristor Input-Protection Device Suitable for CMOS RF IC’s

Based on simulation results and accompanying analysis, we suggest a thyristor-type ESD protection device structure suitable for implementation in standard CMOS processes to reduce the parasitic capacitances added to the input nodes, which is very important in CMOS RF ICs. We compare DC breakdown characteristics of the suggested device to those of a conventional NMOS protection device to show the benefits of using the suggested device for ESD protection. The characteristic improvements are demonstrated and the corresponding mechanisms are explained based on simulations. Structure dependencies are also examined to define the optimal structure. AC simulation results are introduced to estimate the magnitude of reduction in the added parasitic capacitance when using the suggested device for ESD protection. The analysis shows a possibility of reducing the added parasitic capacitance down to about 1/45 of that resulting with a conventional NMOS protection transistor, while maintaining robustness against ESD.Jin-Young Choi was born in Seoul, Korea in 1956. He received the B.S. degree in electrical engineering from the Seoul National University, Korea, in 1979, and the M.S. and Ph.D. degrees in electrical engineering from the University of Florida, USA, in 1986 and 1991, respectively. In 1991, he joined Samsung Electronics Memory Division, Korea, where he was engaged in high-speed SRAM development. In 1992, he moved to the Hongik University, Jochiwon, Korea, where he is now an associate professor. His recent research interests include the high-frequency modeling of CMOS devices, CMOS RF circuit design, and analysis & design for ESD protection.Woo Suk Yang was born in Seoul, Korea in 1957. He received the B.S. degree in electrical engineering from the Seoul National University, Korea, in 1979, and the Ph.D. degree in electrical and computer engineering from the North Calorina State University, USA, in 1990. His doctorial research was in the area of signal processing. In 1990, he joined LG Electronics Co. Korea. In 1991, he moved to the Hongik University, Jochiwon, Korea, where he is now a professor. His recent research interests include the high-frequency modeling and various topics in signal processing area.Dongmin Kim was born in Korea in 1956. He received the B.S. and M.S. degrees in electrical engineering from the Seoul National University, Korea, in 1979 and 1984, respectively and the Ph.D. degree in ECE from the University of Michigan, USA, in 1996. Now, he is an assistant professor of the Hongik University, Jochiwon, Korea. His recent research interests include circuit design and analysis.Youngju Kim was born in Seoul, Korea in 1957. He received the B.S. and M.S. degrees in electrical engineering from the Seoul National University, Korea in 1980 and 1985, respectively and the Ph.D. degree in electrical engineering from the Polytechnic University of New York, USA, in 1995, respectively. In 1996, he joined the Hongik University, Jochiwon, Korea, where he is now an assistance professor. His recent research interests include the RF circuit design and LIN wireless systems.