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Control valve is a kind of essential terminal control component which is hard to model by traditional methodologies because of its complexity and nonlinearity. This paper proposes a new modeling method for the upstream pressure of control valve using the least squares support vector machine (LS-SVM), which has been successfully used to identify nonlinear system. In order to improve the modeling performance, the fruit fly optimization algorithm (FOA) is used to optimize two critical parameters of LS-SVM. As an example, a set of actual production data from a controlling system of chlorine in a salt chemistry industry is applied. The validity of LS-SVM modeling method using FOA is verified by comparing the predicted results with the actual data with a value of MSE 2.474 × 10−3. Moreover, it is demonstrated that the initial position of FOA does not affect its optimal ability. By comparison, simulation experiments based on PSO algorithm and the grid search method are also carried out. The results show that LS-SVM based on FOA has equal performance in prediction accuracy. However, from the respect of calculation time, FOA has a significant advantage and is more suitable for the online prediction.

A hand-held terminal for orchard information collection is designed, which can identify and realize individual plant precision management based on RFID technology. The equipment adopt RS-485 serial bus and MODBUS communication protocol as the general interface for different sensors, to achieve data acquisition requirements including the fruit tree image, air temperature and humidity, soil moisture etc. Meanwhile, build the cloud database that use SIM900A wireless communication module for real-time upload of data, and it can generate nephogram and data analysis report through GPS positioning. Field test results showed that the terminal has high detection accuracy with worked stably and simple operation. Finally, it realized the sharing of sensor information and automatic data acquisition in orchard, with great application and promotion value.

Background: Platelet‐to‐lymphocyte ratio (PLR) is a haematological index which reflects increased level of inflammation and thrombosis. We aimed to summarize the potential prognostic role of PLR for the in‐hospital and long‐term outcomes in ST‐segment elevation myocardial infarction (STEMI) patients treated with primary percutaneous coronary intervention (pPCI) in a meta‐analysis. Materials and methods: Relevant cohort studies were identified by search the PubMed, Cochrane's Library and Embase databases. A random‐effect model was applied to pool the results. In‐hospital and long‐term outcomes were compared between patients with higher and lower preprocedural PLR. Results: Eleven cohorts with 12 619 patients were included. Pooled results showed that higher preprocedural PLR was independently associated with increased risk of in‐hospital major adverse cardiovascular events (MACE, risk ratio [RR]: 1.76, 95% confidence interval [CI]: 1.39 to 2.22, P <.001; I2 = 49%), cardiac mortality (RR: 1.91, 95% CI: 1.18 to 3.09, P =.009; I2 = 0), all‐cause mortality (RR: 2.14, 95% CI: 1.52 to 3.01, P <.001, I2 = 24%) and no reflow after pPCI (RR: 2.22, 95% CI: 1.70 to 2.90, P <.001, I2 = 59%). Moreover, higher preprocedural PLR was associated with increased risk of MACE (RR: 1.60, 95% CI: 1.25 to 2.03, I2 = 57%, P <.001) and all‐cause mortality (RR: 2.36, 95% CI: 1.53 to 3.66, I2 = 78%, P <.001) during long‐term follow‐up of up to 82 months after discharge. Conclusions: Higher PLR predicts poor in‐hospital and long‐term prognosis in STEMI patients after pPCI. [ABSTRACT FROM AUTHOR]