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To study the evolution of stress on the ring and segment interfaces during the construction process of the concrete encapsulation of the main arch ring in a rigid-frame arch bridge, alongside its impact on the ultimate load-bearing capacity of the main arch ring, a 1:10 scale model experiment was conducted by taking the 600 m Tian'e Longtan Bridge as the prototype. The key cross-section concrete strain data were collected during the entire construction process of the main arch ring via fiber-optic strain sensors, which were used to investigate the stress evolution at ring and segment interfaces. ANSYS APDL was employed to simulate the ultimate bearing capacity under various loading conditions of two different finite element models, which were, respectively, formed segmentally and by single pouring. The results revealed that (1) after the closure of the concrete encapsulation of the main arch ring, the concrete stress in the cross-section exhibits significant stress disparities. At the same cross-section, the level of the web concrete stress can reach 76% of the floor concrete stress, while the roof concrete stress level is less than 20% of the floor concrete stress. (2) At the junction of two adjacent work planes, there are considerable differences in the stress levels of the concrete on both sides. After the closure of the main arch ring, the intersegment stress ratios of the floor, web, and roof concrete are 60~70%, 40~60%, and 0~5%, respectively. (3) Loading conditions remarkably affected the ultimate bearing capacity of the main arch ring. Under mid-span loading and 1/4 span symmetrical loading conditions, compared to single-pour concrete encapsulation, the ultimate bearing capacity of the main arch ring with concrete encapsulated by segmented and ring-divided pouring decreased by 19.16% and 5.23%, respectively, compared to single-pour concrete encapsulation. This suggests that the non-uniformity of stress distribution in the concrete sheath can lead to reductions in the ultimate bearing capacity of the arch ring. [ABSTRACT FROM AUTHOR]

In this research, we analyze the acoustic–vibration coupling of liquid-filled cylindrical shells under complex excitations. A calculation model to determine the acoustic characteristics and steady-state response of a cylindrical shell coupled to an acoustic cavity is proposed. The displacement and sound pressure of the cylindrical shell are described by a Chebyshev–Fourier series in three dimensions. The uncertain expansion coefficient is determined with a Rayleigh–Ritz model. The accuracy and convergence of this method are compared with those of the finite element method. The spring constraint is applied to simulate arbitrary boundary parameters. The impact of these parameters on the coupled natural frequency is analyzed. Finally, the steady-state response of a coupled system for various excitation parameters is analyzed. [ABSTRACT FROM AUTHOR]

This paper presents a method to predict the acoustic characteristics and steady-state responses of a flexible plate strongly coupled with rectangular cavity based on energy principle theory and Legendre polynomial series. First, the displacement of the plate and the sound pressure in the cavity are constructed in the form of two-dimensional and three-dimensional Legendre polynomial series, respectively. The unknown expansion coefficients are obtained using the Rayleigh–Ritz technique based on the energy expressions for the strongly coupled plate-cavity system. The accuracy, convergence, and efficiency of the present method are verified by comparing with the results available in the FEM and literature. Finally, the effects of the structural boundary conditions, cavity depth, and structural length-width ratio on the coupling natural frequency and the steady-state responses under three excitation conditions are analyzed. [ABSTRACT FROM AUTHOR]

In this study, by selecting the carrier injection and transport materials and optimizing the thickness of each functional layer in the device, we have solved the problem of unbalanced carrier injection in quantum dot light‐emitting diodes (QLED). The current efficiencies of red, green and blue spin‐coating QLED devices reach 30 cd/A, 70 cd/A, and 8 cd/A, respectively. By continuous optimization of the ink‐jet printing and film‐forming process, the suitable volume of printed ink drops and drying process conditions are obtained, and completed the fabrication of 55‐inch UHD AMQLED display. [ABSTRACT FROM AUTHOR]

This paper proposed a 55 inch 4K AMOLED TV by using Inkjet printing process. The backplane is based on bottom emission structure with Oxide TFTs, and color filter is integrated on array to achieve wide color gamut. The R/G/B pixels are designed with different aperture ratios to avoid white color shirt during the OLED device decay. The inkjet printing process is optimized by backplane pre‐treatment, nozzle stability maintaining and drying process tuning to implement mura‐free display. The prototype TV shows the good display quality with a high degree of uniformity and wide color gamut. It proves that the inkjet printing process is very promising to be used to manufacture the large‐size and low‐cost AMOLED displays. [ABSTRACT FROM AUTHOR]