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The fringe projection profilometry with sinusoidal patterns based on phase-shifting algorithms is commonly distorted by the nonlinear intensity response of commercial projector. In order to solve this issue, sinusoidal width modulation is presented to generate binary sinusoidal patterns for defocusing the projection. However, the residual errors in the phase maps are usually notable for highly accurate three-dimensional shape measurements. In this paper, we propose the fringe patterns of the sinusoidal, square, and triangular periodic waveforms with seven-step phase-shifting algorithm to further improve the accuracy of three-dimensional profile reconstruction. The absolute phase values are calculated by using quality guided path unwrapping. We learn that by properly selecting fringe patterns according to the target shape, the undesired harmonics of the measured surface have negligible effect on the phase values. The experiments are presented to verify the imaging performances of three fringe patterns for different testing targets. The triangular fringe patterns are suitable for the shape measurements of complex targets with curved surfaces. The results provide a great possibility for high-accuracy shape measurement technique with wider measuring depth range.

This paper describes a timing-skew calibration technique which equalizes the phase spacings among multiphase clocks. The scheme uses simple sample-and-hold circuits controlled by the multiphase clocks to sample a common reference input. Phase spacing is measured by counting the number of zero crossings between two adjacent sampling sequences. A zero-crossing detection scheme is proposed. It has better immunity against the offsets of the comparators used in the detector. A digital calibration processor is also proposed. It examines the outputs from the zero-crossing detectors, and then adjusts the delays of clock buffers in order to minimize timing skews. The proposed calibration scheme does not demand stringent requirement for the reference input. Its application to a eight-channel 6-b time-interleaved analog-to-digital converter is demonstrated. Index Terms--Analog-digital conversion, calibration, clocks, phase estimation, time-interleaved, timing circuits, timing skew.

This paper presents a background calibration scheme for pipelined analog-to-digital converters (ADCs) that is robust and has short calibration time. For a switched-capacitor (SC) pipeline stage, by splitting its input sampling capacitor, a random sequence can be injected into the ADC's signal path, and then calibration data can be extracted from the ADC's digital output without interrupting its normal conversion operation. Using an input-dependent scheme to generate the calibration random sequence, no additional signal range is required to accommodate the extra calibration signal. Furthermore, using random choppers to scramble signal can ensure that all necessary calibration data can be collected within a given time regardless of input conditions, resulting in a more robust ADC. A split-channel ADC architecture is proposed to reduce the calibration time. The split-channel ADC consists of two A/D channels that receive the same analog input but employ different random sequences for calibration. The calibration time can be greatly reduced by comparing the digital outputs from both channels and then removing the embedded perturbations before extracting the calibration data. The proposed calibration techniques are analyzed by using both theoretical formulation and system-level simulation. Index Terms--Analog-to-digital (A/D) conversion, calibration, digital background calibration, mixed analog-digital integrated circuits.

Summary: This study evaluated the effects of high hydrostatic pressure (HHP) treatment on the physicochemical composition, level of aromatic compounds and antioxidant properties of mei liqueur, as well as the microstructure of mei fruits during a 180‐day ageing process. The titratable acidity, pH, and browning index of mei liqueur and HHP‐treated mei liqueur did not exhibit significant differences. The HHP‐treated mei liqueur displayed significantly higher ∆E, sugar and alcohol concentration during the 180‐day maceration period (P ≤ 0.05). Electron microscopy revealed that HHP treatment damaged the cellular structure of mei fruits, promoting the penetration of rice wine into the fruits as well as the dissolution of aromatic and antioxidant components into rice wine, leading to the completion of the maturation of the mei liqueur. Thus, HHP technology could be used to accelerate mei liqueur maturation, shorten the time required for its ageing, exhibiting tremendous potential for applications in the liqueur industry. [ABSTRACT FROM AUTHOR]

BACKGROUND This study investigated the effects of high‐pressure processing (HPP) on the glycaemic index (GI) of atemoya puree (AP) in rats. Sprague–Dawley rats were fed with unprocessed and high‐pressure processed atemoya puree (HPP‐AP), and the GIs for the unprocessed AP and HPP‐AP were calculated from changes in blood glucose concentrations within 2 h after meals. The physicochemical properties of AP were analysed to understand the mechanism affecting its GI. RESULTS: The results showed that HPP (600 MPa for 15 min) could delay increase in postprandial blood glucose levels, decrease the peak value of postprandial blood glucose by 76.1%, and significantly decrease the GI of AP to 49.8 in the experimental group compared to 65.4 in the control group. HPP did not exert a significant effect on the glucose and pectin contents of AP, but it increased the viscosity of the puree and its dietary fibre content and delayed the time of peak glucose response. In the analysis of enzymes of the puree, we found that HPP significantly decreased the activities of sucrose invertase, pectin methylesterase and polygalacturonase, thereby decreasing the rate of glucose generation in the puree and stabilizing the pectin structure, which decreased the absorption of glucose by the small intestine, thus decreasing the GI value. CONCLUSION: Our findings suggest that HPP technology could effectively delay increase in postprandial blood glucose levels and decrease the GI value of AP, thus having a potential application in developing atemoya puree products with low GI. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract Background The disease burden and associated medical costs of rotavirus infections in inpatient and outpatient sectors in Taiwan were examined in anticipation of the availability of new rotavirus vaccines. Methods The yearly national case number and medical costs for all for inpatients and outpatients with acute gastroenteritis (AGE) were extracted from the Bureau of National Health Insurance database in Taiwan according to ICD-9-CM codes. A retrospective study was also performed using records of children with AGE seen at three hospitals in Taiwan in 2001 to identify laboratory confirmed rotavirus infection cases. The annual incidence and related medical costs of AGE due to rotavirus infection were then estimated. Results Children Conclusion Infections caused by rotavirus constitute an important human and economic burden among young children in Taiwan. A safe and effective vaccine is urgently needed.