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Solid laser lighting with high photoelectric conversion efficiency and compact size has been increasingly vital in lighting applications. Extensive research has been conducted to obtain high-quality color converters for application to high-power and high-luminance laser lighting. Currently, Y3Al5O12:Ce3+ phosphor in glass (Ce:PiG) and Y3Al5O12:Ce3+ phosphor-in-glass film (Ce:PiF) possessing high efficiency, low cost, easy fabrication, and controllable chromaticity are becoming the most mainstream research directions. In this study, by modifying the glass particle size and sintering temperature, investigating the relevant host glass, and so forth, high-performance Ce:PiG was developed through a one-step co-sintering technology. It possesses a high internal quantum efficiency, approaching 100% of the original phosphors (92.5%). The luminous efficacy (LE) of the Ce:PiG was 240 lm/W at 2.18 W/mm2 under 450 nm blue laser diode (LD) excitation, which is the best result yet reported. Furthermore, to enhance the laser saturation threshold, the fabricated Ce:PiF relying on a sapphire substrate can withstand an 8 W/mm2 blue incident power density. The obtained sample can even reach an LE of 251.5 lm/W, which is an obvious improvement to Ce:PiG. In addition, the result, an LD module combined with the sample that meets the standard white light source, indicates that this work has good prospects for white laser lighting.

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The wireless body area networks (WBANs) have emerged as a highly promising technology that allows patients' demographics to be collected by tiny wearable and implantable sensors. These data can be used to analyze and diagnose to improve the healthcare quality of patients. However, security and privacy preserving of the collected data is a major challenge on resource-limited WBANs devices and the urgent need for fine-grained search and lightweight access. To resolve these issues, in this paper, we propose a lightweight fine-grained search over encrypted data in WBANs by employing ciphertext policy attribute based encryption and searchable encryption technologies, of which the proposed scheme can provide resource-constraint end users with fine-grained keyword search and lightweight access simultaneously. We also formally define its security and prove that it is secure against both chosen plaintext attack and chosen keyword attack. Finally, we make a performance evaluation to demonstrate that our scheme is much more efficient and practical than the other related schemes, which makes the scheme more suitable for the real-world applications.

Under the situations of energy dilemma, energy Internet has become one of the most important technologies in international academic and industrial areas. However, massive small data from users, which are too scattered and unsuitable for compression, can easily exhaust computational resources and lower random access possibility, thereby reducing system performance. Moreover, electric substations are sensitive to transmission latency of user data, such as controlling information. However, the traditional energy Internet usually could not meet requirements. Integrating mobile-edge computing makes energy Internet convenient for data acquisition, processing, management, and accessing. In this paper, we propose a novel framework for energy Internet to improve random access possibility and reduce transmission latency. This framework utilizes the local area network to collect data from users and makes conducting data compression for energy Internet possible. Simulation results show that this architecture can enhance random access possibility by a large margin and reduce transmission latency without extra energy consumption overhead.