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This letter investigates the popularity-aware content caching problem in resource-constrained Cellular-Vehicle-to-Everything (C-V2X) scenarios. A federated Deep Q Network (DQN)-based content caching scheme for vehicle cluster is presented to maximize the fee of caching vehicles. We first cluster vehicles based on their mobility and preferences, and combine historical request frequency with preferences to derive the popularity of the content. Moreover, multiple cluster heads within the coverage area of the Central Server (CS) use DQN to train local caching models, and the CS aggregates local model parameters to obtain a global popular content caching model. Simulation results verify that the proposed scheme outperforms other benchmarks in terms of the cache hit rate and content delivery rate.

High-entropy perovskite oxides (HEPOs) have recently attracted considerable attention due to their unique structure and properties. HEPOs are designed by incorporating multiple principal elements into a single site in perovskite structures. This article provides a review of recent achievements in the application of HEPOs in energy materials. It first presents the development and progress of compositional design strategies for HEPOs. Subsequently, it reviews various structural descriptors for evaluating stability in HEPOs and summarizes synthesis methods of HEPOs with different dimensions. Additionally, it highlights the advantages of HEPOs in various energy-related applications such as dielectric energy storage, piezoelectric materials, solid oxide fuel cells, lithium-ion batteries, thermoelectric materials, catalysts, and supercapacitors. Furthermore, three remaining issues are identified, including the need for a strategy to design compositions based on target performance, the consideration of the influence of geometric and thermodynamic factors on phase formation, and the lack of understanding of the relationship between entropy and performance in HEPOs. The article proposes that future research should focus on function-oriented compositional design strategies that consider the precise relationship between configurational entropy and performance, complemented by accurate structure prediction.

High inverse piezoelectric coefficients are crucial for the effective use of piezoelectric ceramics as actuators. In this study, we focused on the design and preparation of (K0.5-xNa0.5-xSrx) (Nb0.8Ta0.2)O3(x= 0, 0.01, 0.02, 0.03) by defect engineering and investigated the effect of Sr2+doping on its electrical properties. The results showed that a single perovskite phase can be achieved when Sr2+doping is less than 3 mol%. Furthermore, Sr2+doping was found to cause a linear decrease in both the Curie temperature (TC) and the orthorhombic–tetragonal phase transition temperature (TO-T). The ceramic with x= 1% showed optimal piezoelectric properties, exhibiting an electric field-induced strain of 0.124% under a low driving electric field of 20 kV/cm. This corresponds to an inverse piezoelectric coefficient (d33*${d}_{33}^{\ast }$) of 620 pm/V, which is comparable to that of commercial PZT piezoelectric ceramics. This study not only provides potential piezoelectric ceramics for actuators but also serves as a reference for developing high-performance piezoelectric ceramics. A-site vacancies in KNN-based ceramics significantly affect their piezoelectric properties. The addition of Sr to the KNN-based ceramics was shown to modulate the vacancies, resulting in improved piezoelectric properties. When the Sr2+content reached 1 mol%, an increase in the electrostrain of (K0.49Na0.49Sr0.01)(Nb0.8Ta0.2)O3was observed, increasing from 0.008% to 0.124%.

In this study, a series of high-entropy lead-free relaxor ferroelectrics (1-x)(Bi0.4Na0.2K0.2Ba0.2)(Ti0.95Zr0.05)O3–xSr(Mg1/3Nb1/3Ta1/3)O3are designed and synthesized. As xincreases, the corresponding configurational entropy (∆Sconfig) varies from 1.53 R to 2.10 R. The long-range ordered structure of the ferroelectric domains is disrupted, accompanied by the reduced remanent polarization (Pr) and the improved Wrec. When x = 0.09, a high recoverable energy density Wrecof 3.83 J/cm3and a high energy storage efficiency ηof 85.7 % were obtained at an electric field of 360 kV/cm. In addition, the 0.91BNKBTZ-0.09SMNT ceramic sample has excellent performance stability under different temperatures (30–180 °C), cycle times (1–104times) and frequencies (1–100 Hz), making it a reliable candidate as a dielectric for pulsed power systems.

Despite the widely recommended usage of partially hydrolyzed formula (PHF) or extensively hydrolyzed formula (EHF) of milk protein for preventing allergic diseases (ADs), clinical studies have been inconclusive regarding their efficacy compared with that of cow milk formula (CMF) or breast milk (BM). We aimed to systematically evaluate the effects of PHF or EHF compared with those of CMF or BM on risk of ADs (cow milk allergy, allergic rhinitis, eczema, asthma, wheeze, food allergy, and sensitization) in children. We searched PubMed, Embase, Cochrane Library, and Web of Science for clinical trials published from inception to 21 October, 2022. We used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach to grade the strength of evidence. Overall, 24 trials (10,950 infants) were included, 17 of which specifically included high-risk infants. GRADE was low for the evidence that, compared with CMF, infants early fed with EHF had lower risk of cow milk allergy at age 0–2 y [relative risk (RR): 0.62; 95% CI: 0.39, 0.99]. Moderate evidence supported that PHF and EHF reduced risk of eczema in children aged younger or older than 2 y, respectively (RR: 0.71; 95% CI: 0.52, 0.96; and RR: 0.79; 95% CI: 0.67, 0.94, respectively). We also identified moderate systematic evidence indicating that PHF reduced risk of wheeze at age 0–2 y compared with CMF (RR: 0.50; 95% CI: 0.29, 0.85), but PHF and EHF increased the risk compared with BM (RR: 1.61; 95% CI: 1.11, 2.31; and RR: 1.64; 95% CI: 1.26, 2.14). Neither PHF nor EHF had significant effects on other ADs in children of any age. In conclusion, compared with CMF, PHF, or EHF had different preventive effect on cow milk allergy, eczema, and wheeze. Compared with BM, both PHF and EHF may increase risk of wheeze but not other ADs. Given that most trials included only high-risk infants, more research on non–high-risk infants is warranted before any generalization is attempted.

With the increasingly wide range of Internet, the traditional enterprise management model faces enormous challenges, and the user needs are increasingly personalized. How to promote employees to actively promote product services has become an urgent problem for enterprises. Taking Haier Group’s financial control model as the study object, the paper aims to deeply explore how Haier’s financial control model supports the co-evolution of product services and employee competence. The study could help the enterprises to build a financial control model that supports co-evolution of product services and employee competence.

AbstractThe paper use the core principles of critical realism (CR) and Bourdieu’s practice theory to argue how symbolic value arise in the real domain from the relation between the complex assemblages of social, actors and enterprise information system (EIS), how symbolic value are actualized over time by various actors, and how these actualizations lead to the various effects we observe in the empirical domain. It helps to improve the previous implementation method of function oriented, analysis the symbolism and symbolic value hidden behind EIS, and build a theoretical framework of symbolic value releasing from EIS.