Kakia Panagidi

Angelos Dorotheos Chatzopoulos, Babis Andreou, Kakia Panagidi et al.

Modern logistics systems tend to generate continuous streams of data from sources such as GPS, IoT sensors, and logistics management systems. The aggregation, processing, and analysis of data have become vital for monitoring operations, optimizing efficiency, and responding quickly to decision making tasks. In this paper, an event-driven MapReduce framework for real-time data processing in logistics environments is presented. This system runs on Kubernetes with Knative and utilizes Apache Kafka as the backbone for communication between the components. This platform is composed of five loosely coupled services that receive, process, and aggregate the incoming data in real-time. Redis is used to preserve workflow metadata, while an AWS S3 service provides persistent storage for the framework. The design is inspired by the MapReduce programming model. It integrates Function-as-a-Service (FaaS) principles with distributed processing techniques that allow configurable scaling based on the workload demands and the underlying hardware. Experimental evaluation shows that the system can scale effectively as the input data volume increases while supporting scale-to-zero, on-demand processing.

Kakia Panagidi, Stathes Hadjieftymiadis

In modern multimedia systems, efficient video processing is critical, especially in resource-constrained environments such as IoT-based camera networks, autonomous platforms, and wireless sensor multimedia systems. A key bottleneck in video compression and understanding is block motion estimation (ME), a process that remains computationally expensive despite the development of fast search techniques. This work introduces an Optimal Stopping Theory (OST) algorithm for block motion estimation based on the assessment of spatiotemporal differences within and across video frames. It also proposes a semantic-aware motion estimation framework that integrates Foundation Models (FMs) with the OST-based decision process. By leveraging pretrained visual models such as Vision Transformers (ViT) and the Segment Anything Model (SAM), the framework extracts semantic attention scores that indicate the importance of motion within specific spatial regions. These scores are fused with traditional distortion-based metrics, such as the Sum of Absolute Differences (SAD), to guide a hybrid stopping criterion that jointly considers motion magnitude and semantic relevance. The resulting adaptive algorithm stops early in redundant regions while continuing the search in areas where motion is semantically significant. Experiments compare the proposed solution with widely used approaches from the literature on benchmark and multimodal video datasets. The proposed method achieves a significant reduction in computation with minimal accuracy loss and improved semantic coverage. The results highlight the benefits of bridging low-level motion analysis with high-level semantic reasoning, offering a promising direction for efficient multimodal video understanding in next-generation smart systems.