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At present, the research on improving vehicle handling stability, ride comfort, and driving safety mainly focuses on chassis system control, and rarely considers vehicle active aerodynamic control based on aerodynamic characteristics. Therefore, this paper takes the high-speed vehicle with adjustable tail as the research object, and the integrated stability control of active aerodynamics and active rear-wheel steering has been proposed. First, a linear two-degree-of-freedom (2-DOF) vehicle dynamic reference model was established, and the linear quadratic regulator (LQR) active rear-wheel steering controller was designed. Second, the principle of angle of attack distribution for active aerodynamic system was developed, an active aerodynamic Sliding Mode control (SMC) system was designed, which can automatically adjust the angle of attack of the rear wing, according to the vehicle status. Finally, the integrated stability control of active aerodynamics and active rear-wheel steering was realized. In the CarSim and Matlab/Simulink environment, the response characteristics of the integrated control to vehicle handling stability and safety were analyzed. The results show that the integrated stability control can effectively enhance the handling stability, ride comfort, safety, and road tracking ability of the high-speed vehicle, thus reducing the occurrence of vehicle runaway, rollover, and other dangerous situations.

B-train doubles have existed a greater risk of causing accidents. The research on the driver model for combination vehicles is crucial to the active safety control of B-train doubles. The direction control of the driver model forms an invaluable part of the closed-loop simulation of the human-vehicle-road system. Meanwhile, studies of driver models for long combination vehicles (LCVs) are limited. Driver modeling for the articulated heavy vehicle (AHV), a preview driver model for B-train doubles, has been proposed, on the basis of Sliding Mode Control (SMC), considering the low-speed path-tracking and high-speed stability, with the constant speed approach rate and optimal approach rate of the SMC, respectively. The simulation proved that, the proposed driver model can significantly eliminate the chattering phenomena of the front wheel angle, enhance the lateral stability of the B-train doubles, and decrease in peak magnitude of lateral acceleration and yaw angular velocity, and achieve better path following ability.

This report describes a 23 year old woman with a lifelong history of permanent junctional reciprocating tachycardia refractory to conventional antiarrhythmic medications who was successfully treated with closed chest, transvenous selective ablation of a posteroseptal bypass tract. Two 100 J (stored) direct-current shocks were delivered to the region of the os of the coronary sinus using a quadripolar catheter positioned in the coronary sinus. At a 2 month follow-up interval, the patient is asymptomatic without recurrence of the tachycardia. It is concluded that in patients with permanent junctional reciprocating tachycardia, selective catheter ablation of a posteroseptal accessory pathway is a feasible alternative to a difficult pharmacologic regimen or to ablative surgery.

Ten patients with normal sinus node function were evaluated prospectively, to determine whether the decrease in blood pressure during rapid atrial pacing shortens the corrected sinus node recovery time. All patients had 30 seconds of atrial pacing at cycle lengths from 600 to 300 ms, with continuous arterial pressure monitoring, before and after intravenous administration of propranolol (0.2 mg/kg body weight) and atropine (0.04 mg/kg). In the control state, a decrease in corrected sinus node recovery time was recorded with faster atrial pacing rates, which was significantly related to the initial drop in systolic blood pressure at the onset of atrial pacing. Specifically, as the initial pressure drop increased from 15 mm Hg or less to 16 to 45 and 45 to 100 mm Hg, corrected sinus node recovery time decreased from 272 ± 79 to 205 ± 70 ms (p < 0.04) and to 134 ± 120 ms (p < 0.04), respectively. In contrast, after autonomic blockade, the corrected sinus node recovery time was prolonged, in a near linear fashion, as atrial pacing rates increased. The magnitude of blood pressure drop with atrial pacing did not differ significantly from that in the control state at similar pacing rates.