The video question answering task aims to understand video content deeply and answer natural language questions. Current methods based on Multimodal Large Language Models (MLLMs) struggle to model global semantics and temporal dependencies across scenes effectively due to dual constraints of context length and computational complexity, resulting in degraded model inference performance. To address this issue, a Scene-Driven Adaptive Keyframe Sampling (SD-AKS) method and a Question-Driven Video Summarization (QD-VS) method were proposed. First, an iterative video scene clustering based on K-means was introduced, and a Scene Separation Score (SSS) was designed, so as to evaluate feature differences between scenes quantitatively, thereby enhancing the accuracy and robustness of scene segmentation. Second, a problem semantic-guided adaptive keyframe sampling was designed to achieve dynamic keyframe selection based on quantified scene information density and fine coverage of information-dense regions. Furthermore, based on the keyframe method, Large Language Models (LLMs) were employed to summarize the video-related question set, so that the task-oriented textual summaries were generated to improve global model inference capability. Experimental results show that compared to LLaVA?Video, the best?performing baseline model, the proposed method improves prediction accuracy by 5.3 and 1.8 percentage points on the EgoSchema and NExT?QA datasets, respectively, which verifies its effectiveness in cross?dataset scenes.
To address the problems of blurry generation results, detail loss, and uneven feature distribution caused by insufficient local information extraction of the existing models in sign language generation tasks, a sign language generation model based on Kolmogorov-Arnold Network (KAN) and Diffusion Transformer (KDT) was proposed. Firstly, the nonlinear approximation capability of the KAN was utilized to fit complex data distribution, so as to enhance the detail representation and motion fluency between video frames, thereby addressing the blurriness problem of videos generated by traditional Multilayer Perceptron (MLP) models. Then, Contrast Normalization (ContraNorm) was used to replace the original normalization, so as to address the uneven feature distribution problem by calibrating differences in feature scales, thereby ensuring the model’s stability with poor data quality and interference. Finally, diffusion Transformer was employed to achieve refined evolution from random noise to the target sequence through multi-step iterative optimization, thereby addressing the detail loss problem of traditional models. Experimental results on the validation set of RWTH-Phoenix-2014T continuous sign language dataset show that compared to the Sign-IDD (Sign-Iconicity Disentangled Diffusion) model, this model has the BLEU-1 (Bilingual Evaluation Understudy 1-gram) and ROUGE (Recall-Oriented Understudy for Gisting Evaluation) metrics improved by 8.1% and 5.9%, respectively, and the Word Error Rate (WER) metric reduced by 4.5%. The above results verify the effectiveness of this model in enhancing the richness of video details and the fluency of sign language movements.
With the development of wireless communication technology and high-precision mobile positioning technology, Internet of Vehicles (IoV) has become deeply embedded in everyday life. While IoV brings convenience to people, it also brings privacy risks. Typically, in IoV, vehicle driving information interacts with information of other vehicles and infrastructure in real time. During the interaction process, privacy issues such as the leakage of sensitive information may occur. Firstly, the location privacy architecture and privacy risks of IoV were introduced. Secondly, the dynamic noise allocation mechanism, multi-dimensional differential privacy trajectory protection and data perturbation technology in differential privacy were presented. Thirdly, the spatial generalization based on anonymization and the K-anonymity, as well as the asymmetric encryption, symmetric encryption, and homomorphic encryption of encryption mechanism were introduced. Finally, the advantages, disadvantages, limitations and other aspects of differential privacy, anonymity, and encryption mechanisms were analyzed and evaluated.
In order to improve the accuracy of loan financial customer behavior prediction, aiming at the incomplete problem of dealing with non-numerical factors in data analysis of traditional K-Nearest Neighbors (KNN) algorithm, an improved KNN algorithm based on Value Difference Metric (VDM) distance and iterative optimization of clustering results was proposed. Firstly the collected data were clustered by KNN algorithm based on VDM distance, then the clustering results were analyzed iteratively, finally the prediction accuracy was improved through joint training. Based on the customer data collected by Portuguese retail banks from 2008 to 2013, it can be seen that compared with traditional KNN algorithm, FCD-KNN (Feature Correlation Difference KNN) algorithm, Gauss Naive Bayes algorithm, Gradient Boosting algorithm, the improved KNN algorithm has better performance and stability, and has great application value in the customer behavior prediction from bank data.
For the color quantization problem of color images, the K-means clustering algorithm has strong dependence on initial conditions and is easy to fall into local optimum, and the traditional intelligent optimization algorithms only consider the mutual competition between individuals in the population layer and ignores the mutual cooperation between the population layers. To solve the problems, a K-means-based PES (Pyramid Evolution Strategy) color image quantization algorithm was proposed. Firstly, the clustering loss function in K-means clustering algorithm was used as the fitness function of the new algorithm; secondly, PES was used for the population initialization, layering, exploration, acceleration and clustering of the colors; finally, the new algorithm was used to quantify four standard color test images at different color quantization levels. The experimental results show that the proposed algorithm can improve the defects of the K-means clustering algorithm and the traditional intelligent algorithm. Under the criterion of intra-class mean squared error, the average distortion rate of the image quantized by the new algorithm is 12.25% lower than that quantized by the PES-based algorithm, 15.52% lower than that quantized by the differential evolution algorithm, 58.33% lower than that quantized by the Particle Swarm Optimization (PSO) algorithm, 15.06% lower than that quantized by the K-means algorithm; and the less the color quantization levels, the more the image distortion rate reduced quantized by the new algorithm than that quantized by other algorithms. In addition, the visual effect of the image quantized by the proposed algorithm is better than that quantized by other algorithms.