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The demand for power sensors is growing rapidly, and the demand for energy supply is becoming more and more obvious. The disadvantages of the traditional single-battery power supply scheme are becoming more and more obvious. At the same time, with the development of kinetic energy, temperature difference, photovoltaic, electromagnetic and other energy collection technologies and integrated circuit technologies, new ideas are put forward for the energy supply of power sensors. Promoting energy harvesting technology and power sensor coupling in smart grids can improve social benefits and form a win-win situation for all parties. This paper firstly analyzes the urgent demand of smart grid for energy harvesting technology. Secondly, the development status of energy harvesting technology and related integrated circuits is analyzed. Finally, according to the shortcomings of energy harvesting technology in smart grid, the research direction of energy harvesting technology suitable for smart grid is proposed.

In this study, multiple tuned mass dampers (MTMDs) were studied to understand their impact on the human-induced vibration response and comfort level of a pedestrian cable-supported suspension bridge. A spatial finite element model based on a specific engineering case was established. The dynamic characteristics of the bridge under human-induced loads were investigated, and its comfort level under human-induced vibrations was analyzed using the time-history method. Then, this study adjusted the design parameters of the dampers based on various optimal damper parameter expressions. Furthermore, the damping effectiveness of MTMD under different mass ratios ( μ ) was evaluated, and it was found that increasing the mass ratio significantly impacts damping performance. Finally, determinant-TMD (TMDD) was introduced, and a comparison between the damping effect, robustness, and performance of TMDD and MTMD was conducted. The results indicate that while increasing the mass ratio does not linearly affect maximum vibration acceleration, the damping effect increases initially and then stabilizes, with a damping rate converging at approximately 55%. However, with the TMDD approach, the maximum damping rate can reach approximately 70%, enhancing comfort levels from the "minimum CL3" achieved with MTMD to the "medium CL2" level. Additionally, while TMDD's robustness is slightly inferior to MTMD at lower mass ratios, it demonstrates superior robustness at higher mass ratios. [ABSTRACT FROM AUTHOR]

Due to their high flexibility, low damping, and small mass, stay cables are prone to large-amplitude vibrations. Various mechanical measures, typically installed near the cable anchorage to the deck, have been developed to suppress cable vibration. These dampers, however, may not be effective for ultralong cables since the damper is close to the cable anchorage, the cable node. In this paper, a tuned mass damper (TMD)/nonlinear energy sink (NES) are considered for installation between two adjacent stay cables for vibration mitigation. Firstly, the static equilibrium equation of the stay cable–damper system is established, and the influence of the self-weight of the damper on cable shape is investigated. The governing equations describing the motion of the two adjacent cables with a damper are then established using the Hamilton principle, which are then solved by the method of separation of variables. For cases of swept-sine excitation and harmonic excitation, the optimal designs of TMD and NES are achieved with the purpose of suppressing the first- and third-mode-dominated vibrations, respectively. Both optimal TMD and NES may substantially suppress cable vibrations, with each having advantages under certain situations. Finally, the dynamic response characteristics of two adjacent cables with an optimal damper are analyzed. Interesting dynamic behaviors, such as energy input suppression, phase shift, cable frequency shift, and phase diagram boundary rotation, are identified, and their mechanisms are explained. [ABSTRACT FROM AUTHOR]

In this paper, Brazilian disc splitting tests on coal rock specimens with bedding planes and corresponding simulations by combined finite/discrete numerical method(FDEM) were carried out.The results show that the angle of bedding plane have a significant influence on fracture pattern and tensile strength of coal.It is clear that as the angle of weak plane increases, the fracture pattern of models can be classified into four types, including stretching failure perpendicular to weak bedding planes, complicated sketching and shear mixed pattern, shear failure along the bedding planes, and sketching damage along weak bedding planes.As for the difference of tensile strength values, it is observed that when the load is perpendicular to the bedding plane, the effect of bedding structure on calculating tensile strength is negligible and the tensile strength value decreases with the angle rising up to the minimum value as angle reaches vertical.In addition, with respect to dissipated energy of coal samples, it is concluded that the dissipated energy gradually decreases when the angle of bedding planes are increased, which have a relationship with varied fracture patterns and strength values.

An embedded NOR Flash controller is descripted for quickly IAP(in application programming),no need of interrupt vector remap by software, but direct address remap by hardware reboot from middle location with dual Flash banks. The Flash controller can support read operation in the process of IAP, and get right read results. The Flash controller has a 1 ?滋s configuration register which can be used to calculate expected timing values for programming or erase automatically, reducing the software workload to configure more timing values one by one with different working frequency. It is verified after simulation and FPGA prototype verification,and taped out on UMC55 nm process in MCU. The samples of MCU with IAP working well prove further the Flash controller.