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This paper proposes a new algorithm that can simultaneously measure the two-dimensional temperature distribution and absorption coefficient distribution of a pulverized-coal-fired (PCF) boiler furnace. On the base of optimal estimation of the uniform absorption and scattering coefficients as well as 2-D temperature distribution from the color radiation images of the flame by the Tikhonov regularization algorithm, the product of the absorption coefficient and the absolute blackbody emission intensity forms a new unknown distribution of emission source, which is also reconstructed from the color radiation images of the flame by the Tikhonov method. Then the distribution of absorption coefficient can be obtained from the new distribution of emission source as the 2-D temperature distribution has been known. Experimental investigation has been conducted on a 660 MWe four corner, tangentially firing, PCF boiler. In the flame detectors, a three-band pass filter is added in the CCD industrial camera to improve the monochromaticity of the original flame image. The temperature and absorption coefficient distributions of the cross-sections at three detection layers under a load of 330 MW and at the highest layer under a load of 500 MW are obtained. In order to verify the reliability of the algorithm, the flame radiation intensity images calculated from the 2-D distributions of temperature and absorption coefficient reconstructed at the highest layer under the load of 330 MW are taken as measurement data, the algorithm is repeated and the results show that the 2-D temperature distribution reconstructed is similar to the input one, with relative error less than 1% between their mean temperatures, and relative error less than 10% between the reconstructed and input mean values of absorption and scattering coefficients. It demonstrates that the algorithm and technology proposed in this paper have important application prospects in the monitoring, diagnosis and control of PCF combustion processes. [ABSTRACT FROM AUTHOR]

In this study, DNA arrays have been employed to monitor gene expression patterns in testis of mice exposed to tobacco smoke for 24 weeks and compared to control animals. The results of the analysis revealed significant changes in expression of several genes that may have a role in spermatogenesis. Cdk14 was chosen for further characterization because of a suggested role in the testis and in regulation of Wnt signaling. RT-PCR analysis confirmed down regulation of Cdk14 in mice exposed to cigarette smoke (CS). Cdk14 is expressed in all testicular cells; spermatogonia- and Sertoli-derived cell lines treated with cigarette smoke extract (CSE) in vitro showed down-regulation of CDK14 mRNA and protein levels as well as down-regulation of β-catenin levels. CS-induced down-regulation of CDK14 mRNA and protein levels was also observed in several lung epithelium-derived cell lines including primary normal human bronchial epithelial cells (NHBE), suggesting that the effect is not restricted to the testis. Similar to testicular cells, CS-induced down-regulation of CDK14 in lung cells correlated with decreased levels of β-catenin, a finding suggesting impaired Wnt signaling. In the lungs, CDK14 was localized to the alveolar and bronchial epithelium. [ABSTRACT FROM AUTHOR]

This study utilizes high-resolution population grid data from 2004 to 2018 to assess the extent of urban polycentricity in 284 Chinese prefecture-level cities. A new method for measuring urban polycentricity is devised using the Clauset-Newman-Moore grey modularity maximization algorithm. Additionally, the Spatial Durbin Model is applied to investigate the effect of urban polycentricity on the mean and spatial variation of PM 2.5 concentrations. Our statistical results show that the increased distance between urban centers and the increased size disparity between the large and small centers effectively reduces air pollution within the city. On the other hand, in cities with a strong clustering of urban centers and significant size disparity between main and sub-centers, the polycentric urban structure cannot help reduce air pollution but merely shift it to other urban centers within the city. Hence, interpreting the severity of urban air pollution solely on the basis of the citywide average of air pollution may be insufficient. It is necessary to consider the possible relocation of air-polluting activities associated with polycentric urban structures. Policymakers should take into account the potential spatial inequality of air pollution driven by urban polycentricity. [Display omitted] • New algorithm for measuring urban polycentricity (distance dispersion and size disparity of urban centers). • New approach for measuring "urban" air pollution. • Suggested method for addressing the spatial spillover effects of air pollution in data analysis. • Polycentric urban structures reduce air pollution but exacerbate the uneven distribution of air pollution. • Benefits and potential drawbacks of urban polycentricity in mitigating air pollution. [ABSTRACT FROM AUTHOR]

The COVID-19 has become a global pandemic that dramatically impacted human lives and economic activities. Due to the high risk of getting affected in high-density population areas and the implementation of national emergency measures under the COVID-19 pandemic, both travel and transportation among cities become difficult for engineers and equipment. Consequently, the costly physical commissioning of a new manufacturing system is greatly hindered. As an emerging technology, digital twins can achieve semi-physical simulation to avoid the vast cost of physical commissioning of the manufacturing system. Therefore, this paper proposes a digital twins-based remote semi-physical commissioning (DT-RSPC) approach for open architecture flow-type smart manufacturing systems. A digital twin system is developed to enable the remote semi-physical commissioning. The proposed approach is validated through a case study of digital twins-based remote semi-physical commissioning of a smartphone assembly line. The results showed that combining the open architecture design paradigm with the proposed digital twins-based approach makes the commissioning of a new flow-type smart manufacturing system more sustainable. [ABSTRACT FROM AUTHOR]

Digital sensor arrays based on ring oscillators are used to monitor the temperature of Field Programmable Gate Array (FPGA) chips, but traditional sensor structures using binary frequency counters consume excessive hardware logic resources. This paper proposed a compact temperature sensor array that used low-decoding-complexity linear feedback shift registers (LFSR) as a frequency counter to efficiently count the ring oscillator frequency. We implemented an experimental system on a Spartan-6 FPGA, and the logic resource consumption of the entire system was 927 Look-Up-Tables (LUTs) with an overhead of only 10%. The single sampling time was approximately 40 μs. The proposed temperature sensor array has good temperature sensing capabilities, and the measured error is ± 0.9 °C (3 σ). [ABSTRACT FROM AUTHOR]