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In this article, a disturbance estimation–based robust generalized predictive control approach is proposed for angle demand control of a steer-by-wire system. It consists of a generalized predictive controller and a nonlinear disturbance observer. First, the nonlinear disturbance observer is used to estimate the effects of the lumped disturbances, including model uncertainties, unmodeled dynamics, and external disturbances. Second, the estimate of the nonlinear disturbance observer is integrated into the generalized predictive controller design for front-wheel angle output prediction. Then, an explicit analytical form of the disturbance estimation–based robust generalized predictive controller is derived. In addition, rigorous stability analysis proves that the closed-loop system under the proposed control is stable. Finally, the developed control approach has been downloaded into a steering control unit and tested in real-world conditions using a vehicle test bench to fully realize steering by wire in engineering practice. Extensive simulations and experiments have been performed, and results show that the proposed control approach outperforms the comparative controllers regarding disturbance rejection, robust tracking performance under model uncertainties, and disturbances. [ABSTRACT FROM AUTHOR]

Forest fires are a primary driver of biogeochemical processes in ecosystems and affect the soil nutrient balance by altering the distribution of organic matter and associated nutrients as well as the composition and availability of elemental nutrients. We investigated the changes in soils' phosphorus (P) fractions and the adsorption characteristics of potassium dihydrogen orthophosphate (orthoP) and myo‐inositol hexakisphosphate (IHP) at two depths (0–5 and 5–10 cm) in soils from two sites differing in fire severity: long‐unburned and heavily burned. Five years after the fire, there were increases in the total P and extractable inorganic P (H2O‐P, NaHCO3‐Pi, NaOH‐Pi, D.HCl‐Pi and C.HCl‐Pi) contents. Conversely, there was a decrease in organic P (NaHCO3‐Po, NaOH‐Po and C.HCl‐Po). The adsorption of soil for orthoP at a depth of 0–5 cm was dependent on the amount of P supplied by the soil; at low concentrations, heavily burned soil showed a lower adsorption than long‐unburned soil. However, at high concentrations, the adsorption of heavily burned soil was significantly larger than that of long‐unburned soil. With respect to IHP, the adsorption of long‐unburned soil was also more significant at depths of 0–5 cm. The adsorption of both orthoP and IHP of heavily burned soil was significantly higher than that of long‐unburned soil at a depth of 5–10 cm. Fire also decreased the binding degree (k1) of soil‐P and the solid phase at depths of 0–5 and 5–10 cm. The increase in P adsorption capacity outweighed the addition of P from ash, resulting in less leaching in heavily burned areas and minimizing P loss. Overall, forest fires significantly affect the adsorption characteristics and P fractions of soil, specifically orthoP and IHP, during the initial stage of postfire recovery. These effects are closely related to the direct influences of iron oxide, soil organic matter and aluminium oxide in the soil and may even produce relatively long‐term effects on the P recycling process of the entire ecosystem. [ABSTRACT FROM AUTHOR]

Problem‐oriented teaching (POT) activities are important in classroom instruction. The level of student response can be influenced by different teacher behaviours in POT. However, the characteristics of teachers' multimodal behaviours at different levels of response are unclear. This study applied epistemic network analysis to explore the characteristics of teachers' multimodal behaviours in POT with different response levels. Using 256 POT segments from 12 classroom teaching videos in primary and secondary schools, this study found that authentic questions and iconic gestures occupied a central position in multimodal behaviours. The concomitant use of multimodal behaviours and the flexibility in eye contact could improve the response levels of students. These findings help understand how teachers' multimodal behaviours can promote students' responses. Practitioner notesWhat is already known about this topic Various behaviours have been shown to impact learners' response, such as teachers' responses to students and teachers' non‐verbal behaviours.Epistemic network analysis can be used to analyse the structure of the connections between cognitive, social and interaction data.What this paper adds This study analyses the characteristics of teachers' multimodal behaviours during problem‐oriented activities.It also compares the salient properties of non‐verbal, verbal and multimodal behavioural networks generated by interactive fragments of students' responses of different cognitive levels.Implications for practice and policy Teachers should ask more authentic questions in the classroom to promote in‐depth thinking processes in students.The appropriate coordination of multimodal behaviours by teachers is crucial to promote the cognitive level of students' responses.Upon making eye contact with students, teachers should also use iconic gestures and be flexible regarding the use of eye contact. [ABSTRACT FROM AUTHOR]

Correcting the bias of satellite precipitation products (SPPs) based on ground rainfall observations is one effective approach to improve their performance. To date, there have been limited efforts in correcting the bias of hourly SPPs with mixed results. In this study, ratio bias correction (RBC) and probability density matching (PDF) are used to correct the bias of four hourly SPPs (GSMaP_NRT, IMERG_E, IMERG_L, and IMERG) based on ground rainfall observations in a hilly watershed, China. Furthermore, SWAT (Soil and Water Assessment Tool) models are developed using ground rainfall observations, original SPPs, and bias-corrected SPPs to simulate the daily streamflow at the Yuetan Hydrological Station so as to comprehensively compare the performance of the two bias correction methods and evaluate the potentials of the four hourly SPPs in hydrological modeling applications. Our study results show that both RBC and PDF could improve the accuracy of hourly SPPs to various degrees, with PDF outperforming RBC considerably. After being corrected by PDF, the CC values of the four SPPs all reached 0.65. In addition, the SWAT models utilizing the PDF-corrected SPPs simulated the daily streamflow at the Yuetan Station better than those utilizing the RBC-corrected SPPs. Specifically, PDF-corrected IMERG_F performed the best among the four hourly SPPs, with a R2 of 0.89, NSE of 0.89, and RB of −8.14%. After bias correction, hourly satellite precipitation products can be well applied to hydrological modeling in the region. [ABSTRACT FROM AUTHOR]