Browsing by Author "Hung, Y.-T."

An open-loop fractional output divider (FOD) using phase rotating technique is presented. A phase rotating technique is adopted to reduce the dynamic range of digitalto-Time converter (DTC) for output jitter improvement. This prototype is implemented in a 90-nm CMOS process. It can operate over a frequency range of 0.635 MHz to 162.5 MHz. At 160-MHz output frequency, it consumes 6.29 mW from 1-V supply. The measured phase noises at 1-MHz offset is 135.8 dBc/Hz and it achieves 1.19 psrms integrated jitter (10 kHz to 30 MHz). © 2020 IEEE.

High concentration photovoltaic (HCPV) utilizes point-focus cost-effective plastic Fresnel lens. And a millimeter-sized Ill-V compound multi-junction solar cell is placed underneath focusing optics which can achieve cell efficiency potential of up to 40.7 %. The advantage of HCPV makes less solar cell area and higher efficiency; however, the acceptance angle of HCPV is about ±1°, which is very small and the mechanical tracking of the sun is necessary. In order to reduce the power consumption and the angle tracking error of tracking systems, a light collector model with larger acceptance angle is designed with ZEMAX®. In this model, the original radially symmetric Fresnel lens of HCPV is replaced by cylindrically symmetric Fresnel lens and a parabolic reflective surface. Light is collected in two dimensions separately. And a couple of lenses and a light pipe are added before the solar cell chip in order to collect more light when sun light deviates from incident angle of 00. An acceptance angle of ±10° is achieved with GCR 400. © 2009 Copyright SPIE - The International Society for Optical Engineering.

© 2017 Wolters Kluwer Health, Inc. All rights reserved. Background: Although societal preference weights are desirable to inform resource-allocation decision-making, patient experienced health state-based value sets can be useful for clinical decision-making, but context may matter. Objective: To estimate EQ-5D value sets using visual analog scale (VAS) ratings for patients undergoing knee replacement surgery and compare the estimates before and after surgery. Methods: We used the Patient Reported Outcome Measures data collected by the UK National Health Service on patients undergoing knee replacement from 2009 to 2012. Generalized least squares regression models were used to derive value sets based on the EQ-5D-3 level using a development sample before and after surgery, and model performance was examined using a validation sample. Results: A total of 90,450 preoperative and postoperative valuations were included. For preoperative valuations, the largest decrement in VAS values was associated with the dimension of anxiety/depression, followed by self-care, mobility, usual activities, and pain/discomfort. However, pain/discomfort had a greater impact on VAS value decrement in postoperative valuations. Compared with preoperative health problems, postsurgical health problems were associated with larger value decrements, with significant differences in several levels and dimensions, including level 2 of mobility, level 2/3 of usual activities, level 3 of pain/discomfort, and level 3 of anxiety/depression. Similar results were observed across subgroups stratified by age and sex. Conclusions: Findings suggest patient experience-based value sets are not stable (ie, context such as timing matters). However, the knowledge that lower values are assigned to health states postsurgery compared with presurgery may be useful for the patient-doctor decision-making process.