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A novel edge-termination concept using extreme permittivity dielectrics is proposed to effectively manage electric fields in vertical power-devices. This method is expected to be particularly significant for wide band-gap semiconductors, where field termination is a significant challenge due to material and process limitations. Detailed two-dimensional device simulation is used to prove the efficacy of this idea, and to demonstrate that peak electric fields are significantly reduced by this method. We also show an analytical model that gives an intuitive picture into the mechanism of high-permittivity dielectric field plate. Low process complexity and flexibility in the design of power devices can be achieved. We show that junction termination efficiency can be increased from 22.7% (no junction termination) and 50% (conventional field plate) to 73% (high-permittivity-terminated device). [ABSTRACT FROM AUTHOR]

Online product reviews are an important driver of customers' purchasing behavior. Fake reviews seriously mislead consumers, challenging the fairness of the online shopping environment. Although the detection of fake reviews has progressed, several problems remain. First, fake comment recognition ignores the correlation between time and the semantics of the comment texts, which is always hidden in the context of the reviews. Second, the impact of multi-source information on fake comment recognition is not considered, as it constitutes a complex, high-dimensional, heterogeneous relationship between reviewers, reviews, stores and commodities. To overcome these problems, the present paper proposes a dynamic knowledge graph-based method for fake-review detection. Based on the characteristics of online product reviews, it first extracts four types of entities using a developed neural network model called sentence vector/twin-word embedding conditioned bidirectional long short-term memory. Time series related features are then added to the knowledge graph construction process, forming dynamic graph networks. To enhance the fake-review detection, four indicators are newly defined for determining the relationships among the four types of nodes. In experimental evaluations, our method surpassed the state-of-the-art results. [ABSTRACT FROM AUTHOR]

Employing the mixed ligands to react with Cd(NO3)2·4H2O afforded a new 3D coordination polymer [Cd3(BPTC)(bmp)2(ox)(H2O)4] (1) (H4BPTC = biphenyl-3,3′,4,4′-tetracarboxylic acid, bmp = 3,6-bis(imidazol-1-yl)pyridazine, H2ox = oxalic acid), in which ox2− was from the in situ oxidation of ethanol. Compound 1 bears a novel trinodal (4,6,6)-connected net structure, and it is the first replica of the theoretically predicted sqc111 topology net. Moreover, the thermal and photoluminescent properties for 1 were also investigated. [ABSTRACT FROM AUTHOR]