Muhammad Faheem

Ali Zia, Usman Ali, Abdul Rehman et al.

Test-time adaptation (TTA) has emerged as a promising paradigm for mitigating distribution shifts in deep models. However, existing TTA approaches for anomaly segmentation remain limited by their reliance on pixel-level heuristics, such as confidence thresholding or entropy minimisation, which fail to preserve structural consistency under noise and texture variation. Moreover, they typically treat anomaly maps as flat intensity fields, ignoring the higher-order spatial relationships that characterise complex defect geometries. We introduce TopoTTA (Topological Test-Time Adaptation), a novel framework that integrates persistent homology, a tool from topological data analysis, into the TTA pipeline to enforce geometric and structural coherence during adaptation. By applying multi-level cubical complex filtration to anomaly score maps, TopoTTA derives robust topological pseudo-labels that guide a lightweight test-time classifier, enhancing segmentation quality without retraining the backbone model. The approach avoids reliance on method-specific raw-score thresholding for mask binarisation, preserves connectivity, and generalises across both 2D and 3D modalities. Extensive experiments across six standard benchmarks (MVTec AD, VisA, Real-IAD, MVTec 3D-AD, AnomalyShapeNet, and MVTec LOCO) demonstrate an average 15% F1 improvement over state-of-the-art unsupervised anomaly detection and segmentation methods, with the largest gains on anomalies exhibiting complex geometric or structural variations. These findings suggest that integrating topological reasoning into test-time adaptation provides a principled route to structure-aware generalisation, bridging the gap between geometric learning and robust adaptation.

Muhammad Faheem, M-Tahar Kechadi, Nhien-An Le-Khac

Smartphones have become popular in recent days due to the accessibility of a wide range of applications. These sophisticated applications demand more computing resources in a resource constraint smartphone. Cloud computing is the motivating factor for the progress of these applications. The emerging mobile cloud computing introduces a new architecture to offload smartphone and utilize cloud computing technology to solve resource requirements. The popularity of mobile cloud computing is an opportunity for misuse and unlawful activities. Therefore, it is a challenging platform for digital forensic investigations due to the non-availability of methodologies, tools and techniques. The aim of this work is to analyze the forensic tools and methodologies for crime investigation in a mobile cloud platform as it poses challenges in proving the evidence. The advancement of forensic tools and methodologies are much slower than the current technology development in mobile cloud computing. Thus, forces the available tools, and techniques become increasingly obsolete. Therefore, it opens up the door for the new forensic tools and techniques to cope up with recent developments. Hence, this work presents a detailed survey of forensic methodology and corresponding issues in a mobile device, cloud environment, and mobile cloud applications. It mainly focuses on digital forensic issues related to mobile cloud applications and also analyze the scope, challenges and opportunities. Finally, this work reviewed the forensic procedures of two cloud storage services used for mobile cloud applications such as Dropbox and SkyDrive.

Muhammad Faheem, M-Tahar Kechadi, Nhien-An Le-Khac

Smartphones have created a significant impact on the day to day activities of every individual. Now a days a wide range of Smartphone applications are available and it necessitates high computing resources in order to build these applications. Cloud computing offers enormous resources and extends services to resource-constrained mobile devices. Mobile Cloud Computing is emerging as a key technology to utilize virtually unlimited resources over the Internet using Smartphones. Offloading data and computations to improve productivity, enhance performance, save energy, and improve user experience. Social network applications largely utilize Mobile Cloud Computing to reap the benefits. The social network has witnessed unprecedented growth in the recent years, and millions of registered users access it using Smartphones. The mobile cloud social network applications introduce not only convenience but also various issues related to criminal and illegal activities. Despite being primarily used to communicate and socialize with contacts, the multifarious and anonymous nature of social networking websites increases susceptibility to cybercrimes. Taking into account, the advantage of mobile cloud computing and popularity of social network applications, it is essential to establish a forensic framework based on mobile cloud platform that solves the problems of today forensic requirements. In this paper we present a mobile cloud forensic framework that allows the forensic investigator to collect the automated synchronized copies of data on both mobile and cloud servers to prove the evidence of cloud usage. We also show our preliminary results of this study.