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Leakage incidents on LNG bunker vessels will result in a serious degree of hazard. This paper investigates typical high-risk scenarios such as hose ruptures and valve joint leakages. The consequences of an LNG leakage accident during the simultaneous operation of a bunker vessel and a container carrier are simulated using the FLACS software, and the dispersion range of the combustible vapor cloud is quantitatively analyzed under both ballast and laden conditions. Under the ballast condition, the diffusion range of the combustible vapor cloud on the side of the bunker vessel is 58 × 15.5 m from the front wall of the cargo equipment room to the bow of the vessel, and 35 × 9.5 m between the cargo equipment room and the transom of the vessel. Under the laden condition, the diffusion range on the side of the bunker vessel is 58 × 15.5 m from the front wall of the cargo equipment room to the bow of the vessel, and 15 × 4 m between the rear end wall of the cargo equipment room and the front wall of the stern of the vessel. These results provide important technical guidance and reference values for the safe operation of LNG bunker vessels.

Machine learning (ML) for predicting wireless channels of vehicular communications networks has attracted interest in recent years. Beamforming is a technique used to selectively transmit and receive data in a desired direction. The receiver should be capable of choosing the right beam at the right time. The usage of adaptive antenna scanning, i.e., scanning all the beams and choosing the best beam will result only in 30% accuracy, which means 70% of the data will be lost. This article studied a multiagency long short-term memory (LSTM) beamforming prediction model based on signal strength to forecast optimum beams within each beacon interval (BI) for cellular vehicle-to-everything (C-V2X) systems. The model combines the outputs of several parallel prediction models resulting in an enhanced accuracy of prediction. Simulation data validated the effectiveness of the proposed prediction model on the university campus, resulting in a 24% improvement in prediction accuracy.

At present, solid-state laser-driven lighting fabricated with blue laser diode (LD) and phosphor has been greatly developed in high-power lighting applications. The major obstacle is the luminescence saturation threshold of the fluorescence conversion material (YAG:Ce). In this work, we successfully prepared a series of high-quality and robust YAG:Ce single crystals. With high quantum efficiency (QE = 92%), regular crystal structure and high thermal conductivity, the single-crystal has excellent ability to deal with high radiation flux and thermal accumulation generated by high power. Matching the single-crystal with the laser, the luminous efficiency up to 274 lm/W and saturation threshold of 12 W/mm2 were obtained. In addition, the influence of Ce doping concentration and sample processing conditions on the indicators in laser-driven white lighting was systematically studied. The results are of great significance and are believed to promote the development of solid-state laser-driven lighting.

Perovskite has received extensive attention due to its excellent properties, just like photoelectric, while the instability has always troubled us to the wide application of perovskite materials. Herein, we proposed to use SiO2 and POE to encapsulate perovskite nanocrystals (PNCs). In this work, we have successfully prepared a series of perovskite composite materials and films with different concentration ratios. Due to the protection of POE, the luminous intensity of CsPbBr3@POE composite film remained above 90% after stayed in the water for 42 days. The lead concentration of CsPbBr3@POE composite film was 0.8 μg/mL after 48 h of immersing in deionized water. Namely, packaging PNCs in POE could effectively prevent Pb from overflowing reduce Pb pollution. Besides, the composite films showed a wide colour gamut with 117% of NTSC colour gamut, which shows that this composite material has a development prospect in the WLED field.

In this letter, a batch authentication protocol called as accurate bloom-filter-based batch authentication (ABBA) protocol is presented for large-scale radio-frequency identification (RFID) systems. Similar to its predecessor BBA, ABBA can estimate the number of invalid tags contained in an unknown tag set in one communication round by exploiting a bloom filter (BF) vector constructed distributively by the tags. Whereas different from BBA, ABBA adopts a novel BF vector construction method where the randomness caused by valid tags is removed, and thus the estimation is guaranteed to be more accurate and stable than BBA. Both theoretical analysis and extensive simulations confirm the superiority of ABBA over BBA.

The modular LD was packaged with a YAGG:Ce PiG prototype with bright green light observed, which provides a new possibility for long-term and stable LDs.

Stable color converters exhibiting high color rendering index have drawn researchers’ attention for their applications in high-quality white laser lighting. In this study, we develop the multi-color phosphor-in-glass (PIG) with the weight ratio of green-emitting (Y3Al3.08Ga1.92O12:Ce3+) to red-emitting (CaAlSiN3:Eu2+) phosphor powders (10/1–18/1) by low temperature co-sintering method. The obtained composite material displays an outstanding optical and thermal performance, including a high internal quantum efficiency of 84.2%, a high transparency of 45% in the visible region and a low thermal quenching (it remains 86% at 448 K). By integrating 450 nm blue laser diodes with optimized multi-color PIG, the white light with a maximum luminous flux of 258 lm and a luminous efficiency of 137 lm/W is achieved for the first time. Additionally, considering the white balance, by tailoring the weight ratio of green-emitting to red-emitting phosphor and the thickness of PIG, the 14/1 PIG at fixed thickness of 0.75 mm produces pure white light with ultra-high color rendering index of 95.2 and a high luminous efficiency of 120.9 lm/W under power density of 2.39 W/mm2 irradiation. The above superior characteristics imply that the multi-color PIG is an ideal candidate for high-quality white laser lighting applications.

In this work, Eu3+-doped CsPbCl2Br1 in borosilicate glass was successfully synthesized by the melt quenching annealing technique and crystallization method. This work reports a novel Eu3+-doped CsPbCl2Br1 perovskite quantum dots (QDs) glass with high sensitivity for optical temperature sensing. The relation of fluorescence intensity ratio (FIR) with the temperature was studied in the temperature range of 80–440 K. Notably, the maximum absolute temperature sensitivity (Sa) and relative temperature sensitivity (Sr) of Eu3+-doped CsPbCl2Br1 perovskite QDs glass can reach as high as 0.0315 K–1 and 3.097%/K, respectively. Meanwhile, Eu3+-doped CsPbCl2Br1 QDs glass demonstrates good water resistance, excellent thermal and cold cycling stability performance. The Eu3+-doped QDs glass materials can bring inspiration to the future exploration of rare earth ion-doped QDs glass material on the application of optical temperature sensing in the future.