The bionic polarization imaging navigation sensor (BPINS) is a navigation sensor that provides absolute heading, and it is of practical engineering significance to model the measurement error of BPINS. The existing BPINSs are still modeled using photodiode-based measurements rather than imaging measurements and are not modeled systematically enough. This paper proposes a measurement model of BPINS that takes into account the geometric and polarization errors of the optical system. Firstly, the key error factors affecting the measurement accuracy of BPINS are systematically investigated and the Stokes vector-based measurement error model of BPINS is established. Secondly, based on its measurement error model, the effect of the error source on the measurement performance of BPINS is quantitatively analyzed by using Rayleigh scattering to generate scattered sunlight as a known incident light source. The experimental results show that the coordinate deviation of the principal point has a greater impact, followed by grayscale response inconsistency of CMOS and integration angle error of micro-polarization array, and finally lens attenuation. This finding can guide the subsequent calibration of BPINS, and the quantitative results provide an important reference for its optimal design.

In this paper, an improved system to efficiently utilize the low-temperature waste heat (WHUS) from the flue gas of coal-fired power plants is proposed based on heat cascade. The essence of the proposed system is that the waste heat of exhausted flue gas is not only used to preheat air for assisting coal combustion as usual but also to heat up feedwater and the low-pressure steam extraction. Preheated by both the exhaust flue gas in the boiler island and the low-pressure steam extraction in the turbine island, thereby part of the flue gas heat in the air preheater can be saved and introduced to heat the feedwater and the high-temperature condensed water. Consequently, part of the high-pressure steam is saved for further expansion in the steam turbine, which obtains additional net power output. Based on the design data of a typical 1000 MW ultra-supercritical coal-fired power plant in China, in-depth analysis of the energy-saving characteristics of the optimized WHUS and the conventional WHUS is conducted. When the optimized WHUS is adopted in a typical 1000 MW unit, net power output increases by 19.51 MW, exergy efficiency improves to 45.46%, and net annual revenue reaches 4.741 million USD. In terms of the conventional WHUS, these aforementioned performance parameters are only 5.83 MW, 44.80% and 1.244 million USD, respectively. The research of this paper can provide a feasible energy-saving option for coal-fired power plants.

Background: Atherosclerosis (AS), a key pathological contributor of cardiovascular diseases (CVDs), was characterized by formation of atherosclerotic plaque in aortic wall and caused high mortality and morbidity worldwide. Factors contributing to the initiation and progression of AS included vascular endothelial dysfunction, dyslipidemia, inflammation, and oxidative stress. Shexiang Baoxin Pill (SBP) was a traditional Chinese medicine that had been widely applied in clinic and proved to be effective for patients with CVDs. However, the mechanisms underlying its anti-atherosclerotic effects have not been completely elucidated. The study aimed to investigate the protective effects of SBP on AS and its potential mechanisms. Methods: Different dose of SBP was orally administered in apolipoprotein E-deficient (ApoE-/-) mice treated with a high-fat diet (HFD). Histopathological and immunohistochemical analysis, ELISA, untargeted metabolomics analysis, 16S rRNA sequence analysis, and spearman analysis were applied to identify the protective effects and mechanisms of SBP in HFD-induced AS. Results: SBP significantly alleviated HFD-induced atherosclerotic lesion both in aorta and aortic sinus with a reduction in serum levels of total cholesterol (TC), triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C), as well as interleukin-6 (IL-6) and interleukin-1β (IL-1β), and increased high-density lipoprotein cholesterol (HFD-C) level with no significant change of body weight in HFD-induced ApoE-/- mice. Mechanismly, SBP markedly reshaped the gut microbiota composition and associated metabolomic characteristics. 2 differential intestinal floras at phylum level and 8 differential microbes at genus level, 5 metabolic pathways and 9 differential fecal metabolites related to CVDs were figured out. Besides, intensive correlation between 8 differential microbes and 9 fecal metabolites was observed. Conclusions: Our results showed that SBP could improve HFD-triggered serum lipid disorder, systematic inflammation, and contribute to the alleviation of atherosclerotic lesion. The antiatherogenic properties of SBP might partly result from the reshaping of the gut microbiota and fecal metabolic profile.