Goto

Collaborating Authors

 mohammadi


Iranian Nobel laureate handed further prison sentence, lawyer says

BBC News

Nobel Peace Prize winner Narges Mohammadi has been handed further prison sentences of seven-and-a-half years by an Iranian court, her lawyer has said. The human rights activist was sentenced to six years for gathering and collusion, and one-and-a-half years for propaganda activities by a court in the north-eastern city of Mashhad, Mostafa Nili announced on social media on Sunday. Mohammadi was arrested in December for making provocative remarks at a memorial ceremony, Iranian authorities said at the time. Her family said she was taken to hospital after being beaten during the arrest . The 53-year-old was made a Nobel laureate in 2023 for her activism against female oppression in Iran.


Conflict-Free Flight Scheduling Using Strategic Demand Capacity Balancing for Urban Air Mobility Operations

Hemmati, Vahid, Ayalew, Yonas, Mohammadi, Ahmad, Ahmari, Reza, Kebria, Parham, Homaifar, Abdollah, Saif, Mehrdad

arXiv.org Artificial Intelligence

Abstract-- In this paper, we propose a conflict-free multi-agent flight scheduling that ensures robust separation in constrained airspace for Urban Air Mobility (UAM) operations application. First, we introduce Pairwise Conflict A voidance (PCA) based on delayed departures, leveraging kinematic principles to maintain safe distances. Next, we expand PCA to multi-agent scenarios, formulating an optimization approach that systematically determines departure times under increasing traffic densities. Performance metrics, such as average delay, assess the effectiveness of our solution. Through numerical simulations across diverse multi-agent environments and real-world UAM use cases, our method demonstrates a significant reduction in total delay while ensuring collision-free operations. This approach provides a scalable framework for emerging urban air mobility systems.


An Experimental Study of Trojan Vulnerabilities in UAV Autonomous Landing

Ahmari, Reza, Mohammadi, Ahmad, Hemmati, Vahid, Mynuddin, Mohammed, Mahmoud, Mahmoud Nabil, Kebria, Parham, Homaifar, Abdollah, Saif, Mehrdad

arXiv.org Artificial Intelligence

This study investigates the vulnerabilities of autonomous navigation and landing systems in Urban Air Mobility (UAM) vehicles. Specifically, it focuses on Trojan attacks that target deep learning models, such as Convolutional Neural Networks (CNNs). Trojan attacks work by embedding covert triggers within a model's training data. These triggers cause specific failures under certain conditions, while the model continues to perform normally in other situations. We assessed the vulnerability of Urban Autonomous Aerial Vehicles (UAAVs) using the DroNet framework. Our experiments showed a significant drop in accuracy, from 96.4% on clean data to 73.3% on data triggered by Trojan attacks. To conduct this study, we collected a custom dataset and trained models to simulate real-world conditions. We also developed an evaluation framework designed to identify Trojan-infected models. This work demonstrates the potential security risks posed by Trojan attacks and lays the groundwork for future research on enhancing the resilience of UAM systems.


GPS Spoofing Attack Detection in Autonomous Vehicles Using Adaptive DBSCAN

Mohammadi, Ahmad, Ahmari, Reza, Hemmati, Vahid, Owusu-Ambrose, Frederick, Mahmoud, Mahmoud Nabil, Kebria, Parham, Homaifar, Abdollah, Saif, Mehrdad

arXiv.org Artificial Intelligence

Abstract-- As autonomous vehicles become an essential component of modern transportation, they are increasingly vulnerable to threats such as GPS spoofing attacks. This study presents an adaptive detection approach utilizing a dynamically tuned Density Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm, designed to adjust the detection threshold (ε) in real-time. The threshold is updated based on the recursive mean and standard deviation of displacement errors between GPS and in-vehicle sensors data, but only at instances classified as non-anomalous. Furthermore, an initial threshold, determined from 120,000 clean data samples, ensures the capability to identify even subtle and gradual GPS spoofing attempts from the beginning. T o assess the performance of the proposed method, five different subsets from the real-world Honda Research Institute Driving Dataset (HDD) are selected to simulate both large and small magnitude GPS spoofing attacks. The modified algorithm effectively identifies turn-by-turn, stop, overshoot, and multiple small biased spoofing attacks, achieving detection accuracies of 98.62 1%, 99.96 0.1%, 99.88 0.1%, and 98.38 0.1%, respectively. This work provides a substantial advancement in enhancing the security and safety of A Vs against GPS spoofing threats.


Identifying Gender Stereotypes and Biases in Automated Translation from English to Italian using Similarity Networks

Mohammadi, Fatemeh, Tamborini, Marta Annamaria, Ceravolo, Paolo, Nardocci, Costanza, Maghool, Samira

arXiv.org Artificial Intelligence

This paper is a collaborative effort between Linguistics, Law, and Computer Science to evaluate stereotypes and biases in automated translation systems. We advocate gender-neutral translation as a means to promote gender inclusion and improve the objectivity of machine translation. Our approach focuses on identifying gender bias in English-to-Italian translations. First, we define gender bias following human rights law and linguistics literature. Then we proceed by identifying gender-specific terms such as she/lei and he/lui as key elements. We then evaluate the cosine similarity between these target terms and others in the dataset to reveal the model's perception of semantic relations. Using numerical features, we effectively evaluate the intensity and direction of the bias. Our findings provide tangible insights for developing and training gender-neutral translation algorithms.


Towards Efficient Deployment of Hybrid SNNs on Neuromorphic and Edge AI Hardware

Seekings, James, Chandarana, Peyton, Ardakani, Mahsa, Mohammadi, MohammadReza, Zand, Ramtin

arXiv.org Artificial Intelligence

This paper explores the synergistic potential of neuromorphic and edge computing to create a versatile machine learning (ML) system tailored for processing data captured by dynamic vision sensors. We construct and train hybrid models, blending spiking neural networks (SNNs) and artificial neural networks (ANNs) using PyTorch and Lava frameworks. Our hybrid architecture integrates an SNN for temporal feature extraction and an ANN for classification. We delve into the challenges of deploying such hybrid structures on hardware. Specifically, we deploy individual components on Intel's Neuromorphic Processor Loihi (for SNN) and Jetson Nano (for ANN). We also propose an accumulator circuit to transfer data from the spiking to the non-spiking domain. Furthermore, we conduct comprehensive performance analyses of hybrid SNN-ANN models on a heterogeneous system of neuromorphic and edge AI hardware, evaluating accuracy, latency, power, and energy consumption. Our findings demonstrate that the hybrid spiking networks surpass the baseline ANN model across all metrics and outperform the baseline SNN model in accuracy and latency.


Hybrid Indoor Localization via Reinforcement Learning-based Information Fusion

Salimibeni, Mohammad, Mohammadi, Arash

arXiv.org Artificial Intelligence

The paper is motivated by the importance of the Smart Cities (SC) concept for future management of global urbanization. Among all Internet of Things (IoT)-based communication technologies, Bluetooth Low Energy (BLE) plays a vital role in city-wide decision making and services. Extreme fluctuations of the Received Signal Strength Indicator (RSSI), however, prevent this technology from being a reliable solution with acceptable accuracy in the dynamic indoor tracking/localization approaches for ever-changing SC environments. The latest version of the BLE v.5.1 introduced a better possibility for tracking users by utilizing the direction finding approaches based on the Angle of Arrival (AoA), which is more reliable. There are still some fundamental issues remaining to be addressed. Existing works mainly focus on implementing stand-alone models overlooking potentials fusion strategies. The paper addresses this gap and proposes a novel Reinforcement Learning (RL)-based information fusion framework (RL-IFF) by coupling AoA with RSSI-based particle filtering and Inertial Measurement Unit (IMU)-based Pedestrian Dead Reckoning (PDR) frameworks. The proposed RL-IFF solution is evaluated through a comprehensive set of experiments illustrating superior performance compared to its counterparts.