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The integration of control systems with modern information technologies has posed potential security threats for critical infrastructures. The communication channels of the control system are vulnerable to malicious jamming and Denial-of-Service (DoS) attacks, which lead to severe timedelays and degradation of control performances. In this paper, we design resilient controllers for cyber-physical control systems under DoS attacks. We establish a coupled design framework which incorporates the cyber configuration policy of Intrusion Detection Systems (IDSs) and the robust control of dynamical system. We propose design algorithms based on value iteration methods and linear matrix inequalities for computing the optimal cyber security policy and control laws. We illustrate the design principle with an example from power systems. The results are corroborated by numerical examples and simulations.

Compared with conventional image sensors, event cameras have been attracting attention thanks to their potential in environments under fast motion and high dynamic range (HDR). To tackle the lost‐track issue due to fast illumination changes under HDR scene such as tunnels, an object tracking framework has been presented based on event count images from an event camera. The framework contains an offline‐trained detector and an online‐trained tracker which complement each other: The detector benefits from pre‐labelled data during training, but may have false or missing detections; the tracker provides persistent results for each initialised object but may suffer from drifting issues or even failures. Besides, process and measurement equations have been modelled, and a Kalman fusion scheme has been proposed to incorporate measurements from the detector and the tracker. Self‐initialisation and track maintenance in the fusion scheme ensure autonomous real‐time tracking without user intervene. With self‐collected event data in urban driving scenarios, experiments have been conducted to show the performance of the proposed framework and the fusion scheme.

In this work, two series of linear-comb and star-comb well defined graft poly(L-lactide) (PLLA) have been synthesized conveniently by one-pot ring-opening polymerization (ROP) of L-lactide using functionalized polybutadiene macroinitiators. The used organocatalyst of 1, 8-diazabicyclo[5,4,0]undec-7-ene (DBU) allows the polymerization of L-lactide proceeds rapidly at room temperature. Kinetic studies of the ROP reaction in this system indicate a first-order kinetic in monomer concentration.1 H NMR and GPC techniques are employed to characterize the synthesized polymers, validating the formation of desired comb structures with controllable chain length. Linear-comb and star-comb graft PLLA were comparatively studied as well as with linear PLLA by DSC and POM. The results reveal that comb structure makes a remarkable improvement of PLLA crystallization ability in both crystallinity and growth rate of spherulites. Furthermore, the more compacted star-comb structure imposes restriction on chain mobility, which weakens the growth effect to some extent. It is found that the glass transition temperature (Tg) and melting temperature (Tm) significantly depend on the side chain length and backbone structure. Rheological studies of both melt and instinct viscosity of the solution show that star-comb PLLA has the lowest hydrodynamic volume compared with linear-comb PLLA and linear PLLA.Polylactide (PLA) derived from renewable resources has drawn significant attention due to its well biodegradable/biocompatible properties and the other concerns associated with the use of petroleum-based products. 1-3 High molecular weight PLA and its copolymers are one of the most widely utilized polymers in the field of biomedical materials 4-8 . Due to the extremely high mechanical strength, it has been used as commodity and industrial materials as well as clinically in medical applications, 9-10 orthopaedic screw, 11-12 scaffolds, 13-15 etc.PLA can be directly prepared from lactic acid by polycondensation under azeotropic distillation conditions referred as poly(lactic acid) [16][17][18] . Ring-opening polymerization (ROP) of lactide is another effective route to synthesize PLA with higher molecular weight and lower polydispersity 19 . Stannous octoate (Sn(Oct)2) is the most common catalyst for ROP of lactide 20 . However, tin based catalysts are less than ideal from both chemical and biological perspective. The organic catalysts now appear as viable substitutes for classical metallic catalysts 21-23 .Non-metallic ROP processes are demanded for sustainable and environmentally friendly products, especially in microelectronic 24 and biomedical 25-26 applications. In 2001, Hedrick et al. first reported N-heterocyclic carbenes as novel metal-free nucleophilic catalysts for the ROP of cyclic ester monomers 27 . Among those catalysts, the commercial available amidine and guanidine (such as 1,5,7-triazabicyclo[4,4,0]dec-5-ene (TBD) and 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU)) provide better control of molecular weight and highly efficient at room...