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The dynamic control of terahertz (THz) wave transmission on flexible functional materials is a fundamental building block for wearable electronics and sensors in the THz range. However, achieving high-efficiency THz modulation and low insertion loss is a great challenge while maintaining the excellent flexibility and stretchability of the materials. Herein, we report a Ti 3 C 2 T x MXene/waterborne polyurethane (WPU) membrane prepared by a vacuum-assisted filtration method, which exhibits excellent THz modulation properties across stretching. The hydrophilic Ti 3 C 2 T x MXene and WPU enable the uniform 3D distribution of Ti 3 C 2 T x MXene in the WPU matrix. Particularly, the stretchability with the maximum strain of the membranes can reach 200%, accompanied by dynamic tuning of THz transmittance for more than 90% and an insertion loss as low as −4.87 dB. The giant THz modulation continuously decreases with MXene content per unit area, accompanied by a lower density of the MXene interface and diminished THz absorption during stretching. Such a design opens a pathway for achieving flexible THz modulators with a high modulation depth and low insertion loss, which would be used for THz flexible and wearable devices.

With the continuous expansion of the scale of the power grid and the continuous increase in the proportion of new energy and power electronic equipment, higher requirements are placed on the basic data of the online security analysis of the power grid. This paper proposes a multi-source data integration system for large power grid operation. It studies the rapid interaction and intelligent integration of multi-source heterogeneous information such as offline and online models, breaking the technical application barriers of various types of data, and quickly generating real-time power grid model. The analysis model provides a reliable data basis for the online analysis of the power grid. Finally, based on the PSASP simulation software, the correctness and effectiveness of the multi-source data integration system of large power grid are verified.

The paper proposes a method to identify bus split by Innovation Graph Technique. The branch/bus model is utilized in the method. Every possible splitting bus is selected as suspicious bus based on the large magnitude of innovation elements of the branches connecting to the bus. The method first determines the split mode of suspicious bus and then identifies the true bus split, after analyzing the innovation characteristic existing in splitting bus. The advantage of this method is lower measurement redundancy requirement and simpleness in calculation. The example of IEEE-30 bus system demonstrates that this method can identify bus split, and the method can identify the multi topology error situation when branch topology error and bus split take place simultaneously. Index Terms-bus split; generalized breaker model; Innovation GraphTechnique; topology error