Fibrous material with high strength and large stretchability is an essential component of high‐performance wearable electronic devices. Wearable electronic systems require a material that is strong to ensure durability and stability, and a wide range of strain to expand their applications. However, it is still challenging to manufacture fibrous materials with simultaneously high mechanical strength and the tensile property. Herein, the ultra‐robust (≈17.6 MPa) and extensible (≈700%) conducting microfibers are developed and demonstrated their applications in fabricating fibrous mechanical sensors. The mechanical sensor shows high sensitivity in detecting strains that have high strain resolution and a large detection range (from 0.0075% to 400%) simultaneously. Moreover, low frequency vibrations between 0 and 40 Hz are also detected, which covers most tremors that occur in the human body. As a further step, a wearable and smart health‐monitoring system has been developed using the fibrous mechanical sensor, which is capable of monitoring health‐related physiological signals, including muscle movement, body tremor, wrist pulse, respiration, gesture, and six body postures to predict and diagnose diseases, which will promote the wearable telemedicine technology.

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Recently, owing to their excellent flexibility and adaptability, skin-like pressure and strain sensors integrated with the human body have the potential for great prospects in healthcare. This review mainly focuses on the representative advances of the flexible pressure and strain sensors for health monitoring in recent years. The review consists of five sections. Firstly, we give a brief introduction of flexible skin-like sensors and their primary demands, and we comprehensively outline the two categories of design strategies for flexible sensors. Secondly, combining the typical sensor structures and their applications in human body monitoring, we summarize the recent development of flexible pressure sensors based on perceptual mechanism, the sensing component, elastic substrate, sensitivity and detection range. Thirdly, the main structure principles and performance characteristic parameters of noteworthy flexible strain sensors are summed up, namely the sensing mechanism, sensitive element, substrate, gauge factor, stretchability, and representative applications for human monitoring. Furthermore, the representations of flexible sensors with the favorable biocompatibility and self-driven properties are introduced. Finally, in conclusion, besides continuously researching how to enhance the flexibility and sensitivity of flexible sensors, their biocompatibility, versatility and durability should also be given sufficient attention, especially for implantable bioelectronics. In addition, the discussion emphasizes the challenges and opportunities of the above highlighted characteristics of novel flexible skin-like sensors.

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The Fast Fourier Transform (FFT) cannot be directly used to the harmonic analysis of electric power system because of its higher errors, especially the phase error. This paper discussed the leakage phenomenon of FFT and presented a new amending algorithm, poly-item cosine window interpolation, which based on the interpolating algorithm proposed by V. Jain and T. Grandke. This new algorithm obviously improves the accuracy of the FFT, so it can be applied to the precision analysis for electrical harmonic. The simulating result shows that applying different windows has different effects to the accuracy, and the Blackman-Harris window has the highest accuracy. . His main interests and research fields are digital signal processing, wavelet analysis, and vibration analysis.Wei Yuan was born in Xi'an, China. He is working for his M.S. degree in electric engineering in Xi'an Jiaotong University. His main research object is electric harmonic measurement and analysis.

A method for fast design of broadband terahertz diffusion metasurface is presented. The proposed metasurface is composed by three kinds of simply patterned elements with different resonant properties. To obtain the best broadband performance with the lowest backward reflections, a genetic algorithm is developed to manipulate the resonances for the fast determination of element geometries. An inverse discrete Fourier transform method is used to predict the scattering pattern of the metasurface with high accuracy and low time consumption, significantly enhancing the efficiency of the array-pattern design. The proposed fast design flow will benefit a broad range of terahertz applications, such as biological detection and imaging.

Summary The two-dimensional (2D) transition metal dichalcogenides (TMDs) are promising flexible electronic materials for strategic flexible information devices. Large-area and high-quality patterned materials were usually required by flexible electronics due to the limitation from the process of manufacturing and integration. However, the synthesis of large-area patterned 2D TMDs with high quality is difficult. Here, an efficient and powerful pulsed laser has been developed to synthesize wafer-scale MoS 2 . The flexible strain sensor was fabricated using MoS 2 and showed high performance of low detection limit (0.09%), high gauge factor (1,118), and high stability (1,000 cycles). Besides, we demonstrated its applications in real-time monitoring of health-related physiological signals such as radial artery pressure, respiratory rate, and vocal cord vibration. Our findings suggest that the laser-assisted method is effective and capable of synthesizing wafer-scale 2D TMDs, which opens new opportunities for the next flexible electronic devices and wearable health monitoring.