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This paper studies the lateral stability regulation of intelligent electric vehicle (EV) based on model predictive control (MPC) algorithm.

Firstly, the bicycle model is adopted in the system modelling process. To improve the accuracy, the lateral stiffness of front and rear tire is estimated using the real-time yaw rate acceleration and lateral acceleration of the vehicle based on the vehicle dynamics. Then the constraint of input and output in the model predictive controller is designed. Soft constraints on the lateral speed of the vehicle are designed to guarantee the solved persistent feasibility and enforce the vehicle’s sideslip angle within a safety range.

The simulation results show that the proposed lateral stability controller based on the MPC algorithm can improve the handling and stability performance of the vehicle under complex working conditions.

The MPC schema and the objective function are established. The integrated active front steering/direct yaw moments control strategy is simultaneously adopted in the model. The vehicle’s sideslip angle is chosen as the constraint and is controlled in stable range. The online estimation of tire stiffness is performed. The vehicle’s lateral acceleration and the yaw rate acceleration are modelled into the two-degree-of-freedom equation to solve the tire cornering stiffness in real time. This can ensure the accuracy of model.

Chronic kidney disease (CKD) is a worldwide public health problem which imposes a significant financial burden not only on patients but also on the healthcare systems, especially under the pressure of the rapid growth of the elderly population in China. The purpose of this paper is to examine the hospitalization costs of patients with CKD between two urban health insurance schemes and investigate the factors that were associated with their inpatient costs in Guangzhou, China.

This was a prevalence-based, observational study using data derived from two insurance claims databases during the period from January 2010 to December 2012 in the largest city, Guangzhou in Southern China. The authors identified 5,803 hospitalizations under two urban health insurance schemes. An extension of generalized linear model – the extended estimating equations approach – was performed to identify the main drivers of total inpatient costs.

Among 5,803 inpatients with CKD, the mean age was 60.6. The average length of stay (LOS) was 14.4 days. The average hospitalization costs per inpatient were CNY15,517.7. The mean inpatient costs for patients with Urban Employee-based Basic Medical Insurance (UEBMI) scheme (CNY15,582.0) were higher than those under Urban Resident-based Basic Medical Insurance (URBMI) scheme (CNY14,917.0). However, the percentage of out-of-pocket expenses for the UEBMI patients (19.8 percent) was only half of that for the URBMI patients (44.5 percent). Insurance type, age, comorbidities, dialysis therapies, severity of disease, LOS and hospital levels were significantly associated with hospitalization costs.

The costs of hospitalization for CKD were high and differed by types of insurance schemes. This was the first study to compare the differences in hospitalization costs of patients with CKD under two different urban insurance schemes in China. The findings of this study could provide economic evidence for understanding the burden of CKD and evaluating different treatment of CKD (dialysis therapy) in China. Such useful information could also be used by policy makers in health insurance program evaluation and health resources allocation.