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The current world is in an era of the explosive growth in information and rapid renewal. This objective reality puts new demands on education reform. Educational systems and educational models must undergo major changes to meet the needs of creative talent. With the wide application of modern computer technology and network technology, the traditional education structure based on classrooms is constantly changing. In the traditional education process, it emphasizes directly instilling a large amount of knowledge to the students to obtain the quality of teaching. In the network environment, it focuses on cultivating students. Learning methods allow students to have independent knowledge acquisition and also update skills. Online teaching provides a broader and free platform and environment for students' learning. It not only provides rich and colorful teaching resources, but also broadens and breaks the time and space constraints of traditional teaching. The current main method of management of teaching resources is the component teaching resource library, which uses information technology to carry out unified maintenance and management of the teaching resources with increased benefits, and realizes rapid retrieval and convenient use of teaching resources. The numerical verifications are conducted in the final section of the research to verify the performance. [ABSTRACT FROM AUTHOR]

This study does research on resonance and harmonic transmission problems in a new continuous cable traction power supply system (CCTPSS), CCTPSS can realise long-distance co-phase power supply and effectively reduce phase separation and is applicable for extended power supply in areas with the weak power grid. Firstly, the system structure is introduced, a cable traction network is divided into three kinds of subnets for its complicated topology and huge system scale. The equivalent circuit model and mathematical model of each subnet are established with distribution parameters, especially the cable capacitance effect be considered. Then, according to the two-port network analysis theory, the system equivalent circuit is constructed by considering the electrical connection relationship, system harmonic impedance expression is calculated. Resonance influence factors and harmonic transmission mechanisms are analysed. Finally, theoretical analysis validity is verified in simulation; harmonic transmission characteristics CCTPSS including traction cable and overhead catenary, are studied. The new system shows better resonance performance compared with the existing AT traction power supply system. [ABSTRACT FROM AUTHOR]

Phase‐type distribution closure properties are utilized to devise algorithms for generating reliability functions of systems with basic structures. These structures include series, parallel, K‐out‐of‐N, and standby structures with perfect/imperfect switch. The algorithms form a method for system reliability modeling and analysis based on the relationship between the system lifetime and component lifetimes for general structures. The proposed method is suitable for functional system reliability analysis, which can produce reliability functions of systems with independent components instead of only system reliability values. Once the system reliability function is obtained, other reliability measures such as the system's hazard function and mean time to failure can be obtained efficiently using only matrix algebra. Dimensional and numerical comparisons with computerized symbolic processing are also presented to show the superiority of the proposed method. [ABSTRACT FROM AUTHOR]

Based on a sliding mode control, a multi‐area decentralised load frequency control power system with time‐varying delays and non‐linear perturbations is designed in this study. Due to the destabilising effect of delay on the global system, it is necessary to design a control system to accommodate vast time delays so as to manage the deviation in frequency and interchange power. By taking advantage of the system structure and disturbance bounds, robustness is improved. A sliding surface is designed, and the stability of the corresponding sliding motion is analysed based on Lyapunov–Razumikhin function. A delay dependent decentralised sliding mode control is synthesised to drive the system to the sliding surface and maintain a sliding motion afterwards. The obtained results are applied to a two‐area interconnected power system to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This study presents a novel scheme for the synthesis of first‐order and super‐twisting sliding mode controllers for the robust stabilisation of a class of linear time‐invariant time‐delay systems subject to matched disturbances. Starting from a stability analysis of the system to guarantee that the resulting sliding mode dynamics is asymptotically stable, linear matrix inequality conditions of reduced conservatism are derived by using the Lyapunov–Krasovskii approach. Based on the stability analysis, the sliding mode controllers are synthesised to force the evolution of the closed‐loop system trajectories to converge onto a prescribed sliding surface and to ensure that they remain there for all subsequent time. Unlike existing results, the implementation of the proposed approach does not involve strong requirements on the system structure. A numerical and a practical example along with a comparative analysis prove the effectiveness of the proposal and highlight its benefits. [ABSTRACT FROM AUTHOR]

48 V electric system architecture has been recently introduced to accommodate an increasing number of electric components in mild hybrid electric vehicles. In this study, two additional DC buses are added for electric machines including 36 and 24 V AC‐ and DC‐motor/actuator loads, in a 48/12 V power supply system. This structure can yield significant benefits, especially for electrified vehicles that have more electric machines and actuators. A single‐inductor multi‐output structure is employed, with a control strategy that produces linear transfer functions and is less sensitive to load variation, to accommodate multiple‐bus motor/actuator drives. The proposed structure and control strategy can offer options for selecting proper bus voltages, optimising the electric machine's power density. Both simulations and experiments have been performed to verify the system structure and control schemes using 36 and 24 V electric machines connected to the additional dual‐output buses on top of the existing 12/48 V bus structure. [ABSTRACT FROM AUTHOR]

This study addresses the problem of incipient fault detection and diagnosis for Takagi–Sugeno (T–S) fuzzy systems and explores further results of total measurable fault information residual (ToMFIR). First, T–S fuzzy model is used to describe the global dynamics of a non‐linear system and the model of incipient actuator faults is formalised. Second, based on the ToMFIR, a novel incipient fault detection method is proposed, which removes the assumptions on system structure in some existing work. Further, sliding‐mode observers combined with ToMFIR‐based thresholds are designed for incipient fault isolation. Finally, application results conducted on a high‐speed railway traction device are given to illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

An output‐feedback proportional–integral‐derivative‐type control scheme for the global position stabilisation of robot manipulators with bounded inputs is proposed. It guarantees the global regulation objective avoiding input saturation by releasing the feedback not only from the exact knowledge of the system structure and parameter values, but also from velocity measurements. With respect to previous approaches of the kind, the proposed scheme remains simple while increasing design/performance‐adjustment flexibility. For instance, it does not impose the use of a specific sigmoidal function to achieve the required boundedness but involves a generalised type of saturation functions. More importantly, it is characterised by a very simple control‐gain tuning criterion, the simplest hitherto obtained in the considered analytical context. Experimental tests on a 2‐degree‐of‐freedom direct‐drive manipulator corroborate the efficiency of the developed scheme. [ABSTRACT FROM AUTHOR]

The article presents a study on the use of iid Bernoulli components system in the statistical theory of reliability which involves representations such as minimal path set representation and signature representation. The study combined the two representations with the representation of Gibbs measure (GM) for the state of components. Furthermore, the results reveal that the combination of the representations and Gibbs measure yields terms which may be interpreted as system structure complexity.

This paper utilizes a theoretically-grounded model of information systems change together with data from 1891 maintenance projects to test the effects that four factors have on the volatility index of application software. The volatility index is a measure of the relative cost of doing maintenance on the deep structure of a system. Two factors were found to be associated with a higher volatility index, the age of the system and the size of the system. One factor was found to be associated with a lower volatility index, the use of higher-level languages of implementation. One factor was found to be unrelated to the volatility index, the time period when the change was made. Some factors may be under management control, e.g. the language of implementation, while others are usually system characteristics, e.g. system size. Knowledge of the effects of these factors could influence how researchers work with information systems and how information systems management does its work. [ABSTRACT FROM AUTHOR]