National Taiwan University of Science and Technology

About: National Taiwan University of Science and Technology is a education organization based out in Taipei, Taipei, Taiwan. It is known for research contribution in the topics: Fuzzy logic & Control theory. The organization has 16288 authors who have published 21577 publications receiving 426294 citations. The organization is also known as: Taiwan Tech & Taiwantech.

Vitalizing fuel cells with vitamins: pyrolyzed vitamin B12 as a non-precious catalyst for enhanced oxygen reduction reaction of polymer electrolyte fuel cells

Abstract: The limited natural abundance and high cost of Pt has been a major barrier in its applications for hydrogen or methanol fuel cells. In this work, based on the pyrolyzed corrin structure of vitamin B12 (py-B12/C), it is reported to produce superior catalytic activity in the oxygen reduction reaction (ORR) with an electron transfer number of 3.90, which is very close to the ideal case of 4. The H2–O2fuel cell using py-B12/C provides a maximum power density of 370 mW cm−2 and a current density of 0.720 A cm−2 at 0.5 V at 70 °C. Calculations based on density functional theory suggests that the corrin complex with a low-symmetric structure offers a much preferable path for the ORR, which is not applicable to the porphyrin with a high-symmetric structure. The long-term stability and high ORR activity of py-B12/C make it a viable candidate as a Pt-substitute in the ORR.

A Time-Domain SAR Smart Temperature Sensor With Curvature Compensation and a 3σ Inaccuracy of −0.4°C ∼ +0.6°C Over a 0°C to 90°C Range

Abstract: This paper describes a time-domain temperature sensor based on a successive approximation algorithm. Without using any bipolar transistor, a temperature sensor composed of a temperature-dependent delay line (TDDL) is utilized to generate a delay proportional to the measured temperature. A binary-weighted adjustable reference delay line (ARDL) is adopted with an effective delay varied by a SAR control logic to approximate the TDDL delay for output coding. For linearity enhancement, a curvature compensation between both delay lines is invented to achieve the best ever accuracy among inverter-delay-based smart temperature sensors. With two-point calibration, a -0.4°C ˜ +0.6°C inaccuracy (3σ) over a 0°C ˜ 90°C temperature operation range has been measured for 23 test chips. With 10 output bits, the proposed sensor achieves a resolution better than 0.1°C and a chip area of 0.6 mm2 in a TSMC 0.35-μm standard digital CMOS process. The sensor's average current consumption is 11.1 μA at a conversion rate of 2 samples/s.

Adaptive Control for Flexible-Joint Electrically Driven Robot With Time-Varying Uncertainties

Abstract: Almost all present control strategies for electrically driven robots are under the rigid robot assumption. Few results can be found for the control of electrically driven robots with joint flexibility. This is because the presence of the joint flexibility greatly increases the complexity of the system dynamics. What is worse is when some system dynamics are not available and a good performance controller is required. In this paper, an adaptive design is proposed to this challenging problem. A backstepping-like procedure incorporating the model reference adaptive control is employed to circumvent the difficulty introduced by its cascade structure and various uncertainties. A Lyapunov-like analysis is used to justify the closed-loop stability and boundedness of internal signals. Computer simulation results are presented to demonstrate the usefulness of the proposed scheme

Study on the Crystallization, Miscibility, Morphology, Properties of Poly(lactic acid)/Poly(ε-caprolactone) Blends

Abstract: A series of blends of poly(lactic acid) (PLA) and poly(e-caprolactone) (PCL) with different mass ratio were prepared by means of the melt blending method to study their crystallization, miscibility, morphology, and thermal and mechanical properties. The result of DSC tests showed that the melting temperatures of PLA and PCL shifted toward each other, and that the largest shift appeared at the PLA70PCL30 blend. This result reveals that the PLA70PCL30 blend gives the strongest interaction intensity among the blends. Combined the result of dynamic mechanical analysis and SEM morphologies, it was found that PLA and PCL form a partial miscible blend, in which an amount of amorphous PCL (amorphous PLA) is dissolved in the PLA-rich phase (PCL-rich phase), leading to a depression of the Tg. value. The polarized optical micrographs showed that PCL can serve as a nucleating agent to promote PLA crystallization in the PLA/PCL blend. Moreover, the PLA70PCL30 blend gave the largest growth rate of PLA spherulite. Final...