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This study was undertaken to investigate the effect of temperature (25 °C and 30 °C) and nitrogen supplementation (with 20 g/L peptone or without) on bioethanol production from waste bread, waterme...

A CMOS temperature sensor to monitor on-chip distributed thermal profile of high-performance system-on-chips (SoCs) is presented. The architecture of this sensor utilizes a self-discharging p-n diode to implement a first-order delta-sigma ( $\Delta$ - $\Sigma$ ) loop. To determine the on-chip temperature, the temperature-dependent reverse-bias leakage current of the diode is measured. The sensor is implemented in a 0.18- $\mu \text{m}$ CMOS process and it occupies a small area of $550\mu \text{m}^{2}$ . Performance measurements demonstrate the on-chip sensor inaccuracies of ±0.1 °C ( $3\sigma$ ) with calibration, and ±0.5 °C ( $3\sigma$ ) without any calibration, over 35 °C–100 °C, which is the functional temperature range of current high-performance SoCs. The sensor, excluding the digital and any reference generators, consumes $4\mu \text{W}$ from a single 1.8-V supply. The worst case resolution of the sensor is 75 mK at 2-Hz bandwidth with the overall sensor figure of merit of 11 nJ°K2.

Delay and sum beamformed acoustic-resolution photoacoustic images are limited in resolution by the wavelength of the received acoustic signal. We seek to improve on this resolution in the case when the received signal is known to be generated by only a few absorbers. When the absorbers to be imaged are known a priori to be sparse then the reconstruction problem can be stated as an optimization problem aiming to minimize the residual between model predictions and measured channel data and also an L1-norm-based metric of sparsity. In brief, the strategy aims to express experimentally observed curved wavefronts in channel data as a super-position of simulated point-spread functions with a constraint on sparsity. The approach is similar in spirit to recent super-resolution contrast ultrasound approaches but uses an L1-norm minimization strategy. We have applied this optimization strategy to photoacoustic beamforming in both simulation and experiment. Simulation was conducted using Field II, and an experimental measure of resolving power was obtained by imaging the cross section of two wires at successively smaller separations. Experimental channel data was acquired using a 21-MHz Visualsonics array transducers with a Verasonics Vantage ultrasound platform for data acquisition. Simulations indicate potential to beat the ultrasound diffraction limit by a factor of four or more while current experiments achieve a factor of two resolution improvement. A possible application of this approach is for providing increased resolution images of the microvasculature surrounding cancerous tumors. Ongoing work aims to investigate in vivo performance of the proposed sparsity-constrained super-resolution approach.

This paper describes on-chip digital mixing and digital sample rate conversion used to perform mixing for multimedia applications. Digital sample rate conversion facilitates future integration of new features such as wavetable sound synthesis and 3D sound effects processing, while reducing integration time and digital testing costs compared to traditional analog techniques.