Prithwiraj Roy

dblp:284/1754 · DBLP profile ↗
← Back
7ranked-venue papers
3as first author
6since 2021 · last 2024
0000-0002-0592-5593ORCID · corroborated

Domains — the database's venue-derived domains; a paper can count in several

Computer networks · 5 · 2 first-author · 4 since 2021Artificial intelligence and machine learning · 1 · 1 since 2021Security and privacy · 1 · 1 first-author · 1 since 2021Databases, data management, data science and information retrieval · 1 · 1 since 2021
YearPublicationVenuePosition
2024 Quantum Inverse Contextual Vision Transformers (Q-ICVT): A New Frontier in 3D Object Detection for AVs
abstract
The field of autonomous vehicles (AVs) predominantly leverages multi-modal integration of LiDAR and camera data to achieve better performance compared to using a single modality. However, the fusion process encounters challenges in detecting distant objects due to the disparity between the high resolution of cameras and the sparse data from LiDAR. Insufficient integration of global perspectives with local-level details results in sub-optimal fusion performance.To address this issue, we have developed an innovative two-stage fusion process called Quantum Inverse Contextual Vision Transformers (Q-ICVT). This approach leverages adiabatic computing in quantum concepts to create a novel reversible vision transformer known as the Global Adiabatic Transformer (GAT). GAT aggregates sparse LiDAR features with semantic features in dense images for cross-modal integration in a global form. Additionally, the Sparse Expert of Local Fusion (SELF) module maps the sparse LiDAR 3D proposals and encodes position information of the raw point cloud onto the dense camera feature space using a gating point fusion approach. Our experiments show that Q-ICVT achieves an mAPH of 82.54 for L2 difficulties on the Waymo dataset, improving by 1.88% over current state-of-the-art fusion methods. We also analyze GAT and SELF in ablation studies to highlight the impact of Q-ICVT. Our code is available at https://github.com/sanjay-810/Qicvt
Sanjay Bhargav Dharavath, Tanmoy Dam, Supriyo Chakraborty, Prithwiraj Roy, Aniruddha Maiti
CIKM4
2024 Structural Hole Spanners Detection in Directed Social Networks: A Feed Forward Loop Motif Approach
abstract
Structural hole spanners (SHSs) are nodes that connect different communities to facilitate efficient information dissemination in complex networks. Existing efforts to identify SHS nodes have predominantly focused on undirected networks, rendering them inadequate to capture directional data flow. This paper presents a novel lightweight approach to motif span scores, called mSpan that leverages network substructures called feed forward loop (FFL) motifs, to detect SHS in directed, weighted as well as unweighted social networks. The proposed approach measures the spanning score of a node in terms of its participation in FFL motifs that bridge network communities. Our theoretical analysis establishes a strong association between the variants of the scores for a given node and the likelihood of its removal disrupting connectivity. We also utilize mSpan to detect spanner motifs that bridge the structural holes in social networks. We validate the efficacy of mSpan in detecting SHS in practical scenarios through comparative evaluations of three real-world social networks against existing spanner detection metrics.
Arindam Khanda, Satyaki Roy, Prithwiraj Roy, Sajal K. Das 0001
GLOBECOM3
2024 Noise Resilient Learning for Attack Detection in Smart Grid PMU Infrastructure
abstract
Falsified data from compromised Phasor Measurement Units (PMUs) in a smart grid induce Energy Management Systems (EMS) to have an inaccurate estimation of the state of the grid, disrupting various operations of the power grid. Moreover, the PMUs deployed at the distribution layer of a smart grid show dynamic fluctuations in their data streams, which make it extremely challenging to design effective learning frameworks for anomaly based attack detection. In this paper, we propose a noise resilient learning framework for anomaly based attack detection specifically for distribution layer PMU infrastructure, that show real time indicators of data falsifications attacks while offsetting the effect of false alarms caused by the noise. Specifically, we propose a feature extraction framework that uses some Pythagorean Means of the active power from a cluster of PMUs, reducing multi-dimensional nature of the PMU data streams via quick Big Data summarization. We also propose a robust and noise resilient methodology for learning thresholds based on generalized robust estimation theory of our invariant feature. We experimentally validate our approach and demonstrate improved reliability performance using two completely different datasets collected from real distribution level PMU infrastructures.
Prithwiraj Roy, Shameek Bhattacharjee, Sahar Abedzadeh, Sajal K. Das 0001
IEEE Trans. Dependable Secur. Comput.1
2022 Active Learning Augmented Folded Gaussian Model for Anomaly Detection in Smart Transportation
abstract
Smart transportation networks have become instrumental in smart city applications with the potential to enhance road safety, improve the traffic management system and driving experience. A Traffic Message Channel (TMC) is an IoT device that records the data collected from the vehicles and forwards it to the Road Side Units (RSUs). This data is further processed and shared with the vehicles to inquire the fastest route and incidents that can cause significant delays. The failure of the TMC sensors can have adverse effects on the transportation network. In this paper, we propose a Gaussian distribution based trust scoring model to identify anomalous TMC devices. Then we propose a semi-supervised active learning approach that reduces the manual labeling cost to determine the threshold to classify the honest and malicious devices. Extensive simulation results using real-world vehicular data from Nashville are provided to verify the accuracy of the proposed method.
Venkata Praveen Kumar Madhavarapu, Prithwiraj Roy, Shameek Bhattacharjee, Sajal K. Das 0001
ICC2
2021 Influence Spread Control in Complex Networks via Removal of Feed Forward Loops
abstract
Selective removal of certain subgraphs called motifs based on the spread function value is one of the most powerful approaches to curb the overall influence spread in any complex network. In this paper, we first prove that any general spread function preserves both monotonicity and submodularity properties even under motif removal operations. Next, we propose a scoring mechanism as a novel spread function that quantifies the relative importance of a given motif within the overall influence spread dynamics on the complex network. We design a novel algorithm that eliminates motifs with high spread scores to curb influence spread. We evaluate the performance of our proposed spread control algorithm using simulation experiments in the context of 3-node motifs called feed forward loops (FFLs) in both real and synthetic network topologies. We demonstrate that high-scoring motifs intercept a high number of short paths from the pre-assigned source and sinks, because of which their elimination results in a significant effect on curbing the influence spread. Furthermore, we empirically evaluate the run-time and cost versus performance trade-off of the proposed algorithm.
Satyaki Roy, Prithwiraj Roy, V. Sriram Siddhardh Nadendla, Sajal K. Das 0001
ICCCN2
2021 Resilience Against Bad Mouthing Attacks in Mobile Crowdsensing Systems via Cyber Deception
abstract
Mobile Crowdsensing System (MCS) applications deploy rating feedback mechanisms to help quantify the trustworthiness of published events which over time improve decision accuracy and establish user reputation. In this paper, we first show that factors such as sparseness, inherent error probabilities of rating feedback labelers, and prior knowledge of the event trust scoring models, can be used by strategic adversaries to hijack the feedback labeling mechanism itself with bad mouthing attacks. Then, we propose a randomized rating sub-sampling technique inspired from moving target defense and cyber deception to mitigate the degradation in the resulting event trust scores of truthful events. We offer a game theoretic strategy under various knowledge levels of an adversary and the MCS in regards to picking an optimal sub-sample size for bad mouthing attacks and event trust calculations respectively, by using a vehicular crowdsensing as a proof-of-concept.
Prithwiraj Roy, Shameek Bhattacharjee, Hussein Alsheakh, Sajal K. Das 0001
WOWMOM1
2020 Real Time Stream Mining based Attack Detection in Distribution Level PMUs for Smart Grids
abstract
Reliable automation of smart grids depends on decisions based on situational awareness extracted via real time system monitoring and accurate state estimation. The Phasor Measurement Units (PMU) at distribution and transmission layers of the smart grid provide high velocity real time information on voltage and current magnitudes and angles in a three phase electrical grid. Naturally, the authenticity of the PMU data is of utmost operational importance. Data falsification attacks on PMU data can cause the Energy Management Systems (EMS) to take wrong decisions, potentially having drastic consequences on the power grid's operation. The need for an automated data falsification attack detection and isolation is key for EMS protection from PMU data falsification. In this paper, we propose an automated distributed stream mining approach to time series anomaly based attack detection that identifies attacks while distinguishing from legitimate changes in PMU data trends. Specifically, we provide a real time learning invariant that reduces the multi-dimensional nature of the PMU data streams for quick big data summarization using a Pythagorean means of the active power from a cluster of PMUs. Thereafter, we propose a methodology that learns thresholds of the invariant automatically, to prove the predictive power of distinguishing between small attacks versus legitimate changes. Extensive simulation results using real PMU data are provided to verify the accuracy of the proposed method.
Prithwiraj Roy, Shameek Bhattacharjee, Sajal K. Das 0001
GLOBECOM1