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The influence of thermal inertia of the furnace refractory on the peak regulation characteristics of a 300 MW circulating fluidized bed boiler (CFB) was studied by using a numerical calculation method. Based on the actual operation conditions of the boiler, the calculation results reveal that the thermal inertia of refractory is affected by its thermal conductivity and the thickness. Specifically, the thermal inertia of refractory decreases with the increasing thermal conductivity and decreasing refractory thickness. As a consequence, the time that required for the refractory to reach heat equilibrium decreases from 5 812 s to 3 426 s if the thermal conductivity of refractory increases from 1 W/(m⋅K) to 15 W/(m⋅K), while it increases from 3 267 s to 7 771 s if the thickness of refractory material increases from 30 mm to 90 mm. Practically in the presence of the traditional refractory in the CFB dense phase zone, the time required to achieve heat equilibrium state becomes 82, 65 and 60 min when the load of this CFB boiler rises from 50% to 100% with a rate of 1%/min, 2%/min and 3%/min. For a refractory with higher thermal conductivity, the equilibrium response time will be reduced to 65, 46 and 40 min, correspondingly. According to the calculation results, a formula for the heat absorption rate of refractory material was obtained. In addition, the influencing coefficient of the thermal inertia of refractory on coal feeding was also defined and calculated.

Objective To compare the efficacy and outcomes of surgical operations (myotomy and bypass surgery) and coronary stenting for treatment of coronary myocardial bridge. Methods We searched PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure and Wanfang database for studies of treatment of coronary artery myocardial bridge with coronary stenting, myotomy or coronary artery bypass grafting. The data were extracted from the eligible studies, and regression analysis was performed to explore the sources of heterogeneity in the sample size, surgical methods, nations (Asian and others), and year of publication. Results There were 3 584 English articles and 1 678 Chinese articles reviewed in this study, and finially 4 019 articles were recruited after removing duplicate ones. Thirty-three eligible studies involving a total of 1 286 patients were included in the qualitative analysis. A total of 572 patients from 26 studies were included in the quantitative analysis. Analyses of the single rates showed that the overall symptom remission rate of myocardial bridge was 88.00% (95% CI: 81.31%-93.56%) following surgical interventions, which were associated with an overall postoperative coronary artery restenosis rate of 9.09% (95% CI: 4.30%-15.05%) and overall rates of intraoperative complications and postoperative cardiovascular events of 0.59% (95% CI: 0.00%-1.83%) and 0.46% (95% CI: 0.00%-1.63%), respectively. Regression analysis showed that postoperative symptom relief and coronary artery restenosis rates were significantly correlated with the surgical methods used (P < 0.001) but not with the sample size, year of publication, or nationalities of the patients (P > 0.1). Subgroup analysis showed that compared with interventional treatment, surgical treatments resulted in a significantly higher rate of postoperative symptom relief (95.45% vs 68.82%, P < 0.001) and lower rates of coronary artery restenosis (3.89% vs 21.78%, P < 0.001) and postoperative cardiovascular events (0.01% vs 2.91%, P < 0.001). The incidence of intraoperative complications did not differ significantly between surgical and interventional treatments (1.65% vs 0.00%, P=0.1405). Conclusion Surgical treatments result in a higher rate of postoperative symptom relief and a lower postoperative restenosis rate than interventional treatment, but high-quality randomized controlled trials with a large sample size are still needed to verify this conclusion.

At present, the clinical diagnosis of depression is mainly through structured interviews by psychiatrists, which is lack of objective diagnostic methods, so it causes the higher rate of misdiagnosis. In this paper, a method of depression recognition based on SVM and particle swarm optimization algorithm mutation is proposed. To address on the problem that particle swarm optimization (PSO) algorithm easily trap in local optima, we propose a feedback mutation PSO algorithm (FBPSO) to balance the local search and global exploration ability, so that the parameters of the classification model is optimal. We compared different PSO mutation algorithms about classification accuracy for depression, and found the classification accuracy of support vector machine (SVM) classifier based on feedback mutation PSO algorithm is the highest. Our study promotes important reference value for establishing auxiliary diagnostic used in depression recognition of clinical diagnosis.