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Forensic face recognition (FFR) has been studied in recent years in forensic science. Given an automatic face recognition system, output scores of the system are used to describe the similarity of face image pairs, but not suitable for forensics. In this study, a score-mapping model based on kernel density estimation (KDE) and evidence theory is proposed. First, KDE was used to generate probability density function (PDF) for each dimensional feature vector of face image pairs. Then, the PDFs could be utilized to determine separately the basic probability assignment (BPA) of supporting the prosecution hypothesis and the defence hypothesis. Finally, the BPAs of each feature were combined by Dempster’s rule to get the final BPA, which reflects the strength of evidence support. The experimental results demonstrate that compared with the classic KDE-based likelihood ratio method, the proposed method has a better performance in terms of accuracy, sensitivity and specificity.

The standardization of the online government service platform is of great significance to simplify the procedures and improve the efficiency of administrative licensing agencies. In this paper, the definition of online government service platform, from the law, policy background, the practice level, carry out the work of government services online analysis summarizes the necessity, the role of online government service platform and the existing problems, and analysis the reasons from the dimension of standardization, standardization can be targeted to summarize proposed online government service platform construction of three aspects of the role.

Aiming at the needs of criminal investigators to quickly find chat logs related to crime case, a ranking method for chat texts has been proposed. First, query keywords were used to search chat texts, and the feedback texts were divided into relevant texts and irrelevant texts with manual annotation, then non-negative matrix factorization (NMF) was utilized to obtain the implicit semantic relationship of chat texts, finally chat logs could be ranked based on the scores calculated by similarity. Experiments show that the method proposed in this paper can quickly retrieve and get the messages of interest in a lot of chat logs, which can facilitate crime investigation.

Investigation of audible noise characteristics of the main power apparatus in UHV GIS substations provides essential statistics for the noise prediction and control. Noise pressure level, spectrum and attenuation characteristics of the main transformers and high voltage (HV) reactors are measured and analyzed in this paper. The result shows that the main transformer and HV reactor have identical A-weighted equivalent sound pressure level. The medium- and low-frequency noises are the primary components in the spectral. More attention should be paid to the low-frequency bands in the noise control process. The noise of cooling fan has a large influence on that of the main transformer. Without the consideration of corona noise, the average A-weighted sound pressure level shows an overall decreasing trend with the increase of the propagation distance. Obvious interference phenomenon of the noises at 100 and 200Hz exists in the noise propagation process.