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Objective The co-structure system of subway station (hereinafter referred to as 'co-structure system') realizes the connection and conversion between the box structure and the box frame structure through thick plates. Due to the unique structural form of the co-structural system, its seismic response law is currently unclear, further study on the characteristics of its seismic response is needed. Method Taking the co-structure system of a comprehensive utility tunnel and subway station as an example, the finite element simulation model of soil-co-structure system interaction is established. Considering one-way and two-way seismic waves (both horizontal and vertical) as inputs, three working conditions are selected. The acceleration response characteristics, displacement response characteristics, compressive and tensile damage situations, and the evolution process of the co-structure system under seismic action are analyzed. Taking the left column end of the co-structure system as an example, the internal force response characteristics of some structural parts are discussed. Result & Conclusion The vertical acceleration of the co-structure system is greatly affected by the bidirectional coupling ground motion. The maximum increase in acceleration at the joint between the side wall and the negative first floor slab reaches 158 % (compared with the vertical ground motion). Vertical ground motion may increase the relative horizontal and relative vertical displacements in the roof and floor of the co-structure system, and the internal force response of the column as well. Locations of the co-structure system such as the column ends, the lower part of the side wall, both ends of the bottom plate, the connection of the components, and the axillary angle are vulnerable to seismic damage, and should be strengthened accordingly.

Intelligent instrumentation plays a crucial role in industrial applications, with its measurement accuracy and reliability directly influencing operational efficiency. This article presents the integration of the HART communication protocol to enhance data transmission within smart instruments, focusing on internal structure and process control optimization. A HART smart instrument multiplexer system is established, utilizing an analog PID control algorithm for data regulation and optimal control techniques for automatic parameter adjustment. Additionally, the three-parameter Weibull distribution is employed to assess the reliability of smart meters, deriving distribution characteristics and estimating parameters through failure rate analysis. The performance of the designed HART smart meter multiplexer system is thoroughly evaluated, including control performance, reliability, channel function, and measurement accuracy. Notably, the system demonstrates a minimal overshoot in analog PID control at 0.911%, with a steady-state error range of -5°C to 4°C. Furthermore, the implementation of this system significantly reduces the risk of hazardous failures by 41.91%. In conditions of 350°C temperature and 1.2MPa pressure, the system accurately measures superheated steam flow with a relative error of only 0.05%. By optimizing the settings of smart instruments, this system not only enhances measurement accuracy in industrial production but also improves reliability, supporting diverse applications in the chemical industry.

【Objective】 Hetao irrigation district is one of the largest surface water-irrigation districts in north China. Keeping groundwater table below a critical depth is essential to preventing salt accumulation in the root zone, and the purpose of this paper is to study the suitable groundwater depth for healthy growth of different crops. 【Method】 The experimental area is at Jiefangzha within the irrigation district. Planting structure in the area was analyzed using decision tree classification method, and groundwater depth was estimated using the Kriging interpolation method, from which we calculated the mean NDVI. The suitable groundwater depth and salinity threshold for crops at different locations were obtained from the scatter diagram of groundwater salinity and its NDVI. 【Result】 ①The suitable groundwater depth for maize at its jointing, heading and filling stages was 1.2~1.7, 1.3~1.8 m and 1.3~1.8 m, respectively, while for winter wheat, the suitable groundwater depth at its jointing, heading and filling stages was 1.1~1.6, 1.1~1.6 m and 1.2~1.7 m, respectively. The suitable groundwater depth for sunflower at its bud and filling stages was 1.1~1.6 m and 1.2~1.7 m, respectively. ②The groundwater salinity critical for crop growth is 5 g/L, with groundwater salinity in the range of TDS≤3 g/L, 35 g/L being most suitable, suitable and not suitable for crop growth, respectively. 【Conclusion】 Controlling groundwater table at suitable depths with groundwater salinity not exceeding the critical concentration is essential to improving groundwater use efficiency and sustaining crop production in Hetao Irrigation district. For the area we studied, the suitable groundwater depth varies with crops and their growth stages, but the critical groundwater salinity is approximately the same for all crops.

Abstract Background To explore the correlation between the preoperative systemic immune inflammation index (SII) and the prognosis of patients with gastric carcinoma (GC). Methods The clinical data of 771 GC patients surgically treated in the Department of Gastrointestinal Surgery, Qinghai University Affiliated Hospital from June 2010 to June 2015 were retrospectively analyzed, and their preoperative SII was calculated. The optimal cut-off value of preoperative SII was determined using the receiver operating characteristic (ROC) curve, the confounding factors between the two groups were eliminated using the propensity score matching (PSM) method, and the correlation between preoperative SII and clinicopathological characteristics was assessed by chi-square test. Moreover, the overall survival was calculated using Kaplan-Meier method, the survival curve was plotted, and log-rank test was performed for the significance analysis between the curves. Univariate and multivariate analyses were also conducted using the Cox proportional hazards model. Results It was determined by the ROC curve that the optimal cut-off value of preoperative SII was 489.52, based on which 771 GC patients were divided into high SII (H-SII) group and low SII (L-SII) group, followed by PSM in the two groups. The results of Kaplan-Meier analysis showed that before and after PSM, the postoperative 1-, 3-, and 5-year survival rates in L-SII group were superior to those in H-SII group, and the overall survival rate had a statistically significant difference between the two groups (P < 0.05). Before PSM, preoperative SII [hazard ratio (HR) = 2.707, 95% confidence interval (CI) 2.074-3.533, P < 0.001] was an independent risk factor for the prognosis of GC patients. After 1:1 PSM, preoperative SII (HR = 2.669, 95%CI 1.881–3.788, P < 0.001) was still an independent risk factor for the prognosis of GC patients. Conclusions Preoperative SII is an independent risk factor for the prognosis of GC patients. The increase in preoperative SII in peripheral blood indicates a worse prognosis.

Fast capacity estimation for retired batteries is necessary when batteries are recycled for echelon utilization. Here, a fast capacity estimation method is proposed for retired LiFePO4 battery. First, a full survey of battery pack and cells degradation after a long period of service is studied. Then the filtered ICA is used to study degradation variation phenomenon of retired batteries, the relationship between IC curve feature and remaining capacity was studied. Finally, a fast capacity estimation using incremental capacity and Gaussian process regression is proposed. Our results show high efficiency and accuracy of the proposed method.