Passive fault-tolerant control for vehicle active suspension system based on H2/H∞ approach

In this paper, a robust passive fault-tolerant control (RPFTC) strategy based on H2/H∞ approach and an integral sliding mode passive fault tolerant control (ISMPFTC) strategy based on H2/H∞ approach for vehicle active suspension are presented with considering model uncertainties, loss of actuator effectiveness and time-domain hard constraints of the suspension system. H∞ performance index less than γ and H2 performance index is minimized as the design objective, avoid choosing weighting coefficient. The half-car model is taken as an example, the robust passive fault-tolerant controller and the integral sliding mode passive fault tolerant control law is designed respectively. Three different fault modes are selected. And then compare and analyze the control effect of vertical acceleration of the vehicle body and pitch angular acceleration of passive suspension control, robust passive fault tolerant control and integral sliding mode passive fault tolerant control to verify the feasibility and effectiveness of passive fault tolerant control algorithm of active suspension. The studies we have performed indicated that the passive fault tolerant control strategy of the active suspension can improve the ride comfort of the suspension system

The long-term safety and effectiveness of the loop technique in left ventricular lead dislocation

ObjectivesCardiac resynchronization therapy (CRT) is a well-established method that improves the clinical symptoms and long-term prognosis of specific heart failure (HF) patients by restoring systolic synchronicity and enhancing myocardial function. However, the high rate of intraoperative and postoperative left ventricular (LV) lead dislocation limits its application to a great extent. The aim of this study was to demonstrate the long-term safety and effectiveness of a new approach named the loop technique for patients who experience repeated intraoperative transvenous LV lead dislocations during CRT.MethodsThe current study was a single-centre, prospective, nonrandomized controlled trial. Forty-four HF patients who underwent CRT were included. All patients were followed to death or 3 years.ResultsAmong 44 HF patients, 36 underwent the traditional operation, and 8 underwent the loop technique due to repeated intraoperative LV lead dislocations. Intergroup comparison revealed no significant differences between the two groups with respect to most preoperative indices, intraoperative pacing and sensing parameters. At the end of the 3-year follow-up, 4 (11.1%) patients in the traditional operation group and 2 (25.0%) patients in the loop technique group had died. There was no significant difference in the mortality rate (P = 0.30). No complications related to this new technique were observed, such as intracoronary thrombosis, infection or dislocation. Intergroup comparison showed no significant difference in the New York Heart Association (NYHA) class, echocardiography indices, N-terminal pro brain natriuretic peptide (NT-proBNP) level or pacemaker programming parameters.ConclusionsThe loop technique is a safe and effective alternative method for patients who experience repeated intraoperative transvenous LV lead dislocations during CRT

An experimental study on biased cognitive processing in accidentally injured patients with different posttraumatic growth levels

Background: Various studies have assessed the negative and/or positive changes in the aftermath of traumatic events. Accidental injuries (such as accidents, injuries, etc.), for its high incidence and disability rate, is easy to cause serious psychological problems and hinder the physical and psychological rehabilitation of the patients.Material and Methods: To explore the characteristics of attention bias in accidentally injured patients with different levels of Posttraumatic growth (PTG), total score of PTG was adopted to screen out 15 high-PTG group and low-PTG group respectively among accidentally injured patients. Dot probe task was used with positive, negative and neutral facial expression pictures as experimental materials. An experimental design of 2 (facial expression: positive and negative)×2 (consistency of probe point and facial expression: consistent and inconsistent)×2 (PTG level: high and low) was employed.Results: Patients with low PTG level had attention bias toward the negative emotional stimuli, and difficulty in distraction from the negative emotional pictures. The value of D and DI were both significantly greater than 0 (p<0.05). Patients with high PTG level did not demonstrate significant attention bias toward positive or negative emotional stimuli. The responding time of patients with high PTG level was significantly shorter than that in patients with low PTG level in the incongruent task (p<0.05).Conclusion: There are different characteristics of implicit cognitive processing in patients with different level of PTG, suggesting the necessity of psychological intervention on the accidentally injured patients.Keywords: Accidentally injured patients; Posttraumatic growth; Attention bias; Dot probe tas

Simulating the Kibble-Zurek mechanism of the Ising model with a superconducting qubit system

The Kibble-Zurek mechanism (KZM) predicts the density of topological defects produced in the dynamical processes of phase transitions in systems ranging from cosmology to condensed matter and quantum materials. The similarity between KZM and the Landau-Zener transition (LZT), which is a standard tool to describe the dynamics of some non-equilibrium physics in contemporary physics, is being extensively exploited. Here we demonstrate the equivalence between KZM in the Ising model and LZT in a superconducting qubit system. We develop a time-resolved approach to study quantum dynamics of LZT with nano-second resolution. By using this technique, we simulate the key features of KZM in the Ising model with LZT, e.g., the boundary between the adiabatic and impulse regions, the freeze-out phenomenon in the impulse region, especially, the scaling law of the excited state population as the square root of the quenching rate. Our results supply the experimental evidence of the close connection between KZM and LZT, two textbook paradigms to study the dynamics of the non-equilibrium phenomena.Comment: Title changed, authors added, and some experimental data update

Open Design and 3D Printing of Face Shields: The Case Study of a UK-China Initiative

At the start of the COVID-19 outbreak, many countries lacked personal protective equipment (PPE) to protect healthcare workers. To address this problem, open design and 3D printing technologies were adopted to provide much-in-need PPEs for key workers. This paper reports an initiative by designers and engineers in the UK and China. The case study approach and content analysis method were used to study the stakeholders, the design process, and other relevant issues such as regulation. Good practice and lessons were summarised, and suggestions for using distributed 3D printing to supply PPEs were made. It concludes that 3D printing has played an important role in producing PPEs when there was a shortage of supply, and distributed manufacturing has the potential to quickly respond to local small-bench production needs. In the future, clearer specification, better match of demands and supply, and quicker evaluation against relevant regulations will provide efficiency and quality assurance for 3D printed PPE supplies

{1-[(3,5-Dimethyl-4H-1,2,4-triazol-4-yl)imino]eth­yl}ferrocene

In the title compound, [Fe(C5H5)(C11H13N4)], the triazolyl and Cp ring form a dihedral angle of 76.6 (3)°. In the crystal structure, there are both intra- and inter­molecular C—H⋯π inter­actions, forming a one-dimensional chain structure along [010]