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LLMs as Repositories of Factual Knowledge: Limitations and Solutions

arXiv.org Artificial Intelligence

LLMs' sources of knowledge are data snapshots containing factual information about entities collected at different timestamps and from different media types (e.g. wikis, social media, etc.). Such unstructured knowledge is subject to change due to updates through time from past to present. Equally important are the inconsistencies and inaccuracies occurring in different information sources. Consequently, the model's knowledge about an entity may be perturbed while training over the sequence of snapshots or at inference time, resulting in inconsistent and inaccurate model performance. In this work, we study the appropriateness of Large Language Models (LLMs) as repositories of factual knowledge. We consider twenty-four state-of-the-art LLMs that are either closed-, partially (weights), or fully (weight and training data) open-source. We evaluate their reliability in responding to time-sensitive factual questions in terms of accuracy and consistency when prompts are perturbed. We further evaluate the effectiveness of state-of-the-art methods to improve LLMs' accuracy and consistency. We then propose "ENtity-Aware Fine-tuning" (ENAF), a soft neurosymbolic approach aimed at providing a structured representation of entities during fine-tuning to improve the model's performance.


A review on development of eco-friendly filters in Nepal for use in cigarettes and masks and Air Pollution Analysis with Machine Learning and SHAP Interpretability

arXiv.org Artificial Intelligence

In Nepal, air pollution is a serious public health concern, especially in cities like Kathmandu where particulate matter (PM2.5 and PM10) has a major influence on respiratory health and air quality. The Air Quality Index (AQI) is predicted in this work using a Random Forest Regressor, and the model's predictions are interpreted using SHAP (SHapley Additive exPlanations) analysis. With the lowest Testing RMSE (0.23) and flawless R2 scores (1.00), CatBoost performs better than other models, demonstrating its greater accuracy and generalization which is cross validated using a nested cross validation approach. NowCast Concentration and Raw Concentration are the most important elements influencing AQI values, according to SHAP research, which shows that the machine learning results are highly accurate. Their significance as major contributors to air pollution is highlighted by the fact that high values of these characteristics significantly raise the AQI. This study investigates the Hydrogen-Alpha (HA) biodegradable filter as a novel way to reduce the related health hazards. With removal efficiency of more than 98% for PM2.5 and 99.24% for PM10, the HA filter offers exceptional defense against dangerous airborne particles. These devices, which are biodegradable face masks and cigarette filters, address the environmental issues associated with traditional filters' non-biodegradable trash while also lowering exposure to air contaminants.


Unveiling Zero-Space Detection: A Novel Framework for Autonomous Ransomware Identification in High-Velocity Environments

arXiv.org Artificial Intelligence

Modern cybersecurity landscapes increasingly demand sophisticated detection frameworks capable of identifying evolving threats with precision and adaptability. The proposed Zero-Space Detection framework introduces a novel approach that dynamically identifies latent behavioral patterns through unsupervised clustering and advanced deep learning techniques. Designed to address the limitations of signature-based and heuristic methods, it operates effectively in high-velocity environments by integrating multi-phase filtering and ensemble learning for refined decision-making. Experimental evaluation reveals high detection rates across diverse ransomware families, including LockBit, Conti, REvil, and BlackMatter, while maintaining low false positive rates and scalable performance. Computational overhead remains minimal, with average processing times ensuring compatibility with real-time systems even under peak operational loads. The framework demonstrates resilience against adversarial strategies such as obfuscation and encryption speed variability, which frequently challenge conventional detection systems. Analysis across multiple data sources highlights its versatility in handling diverse file types and operational contexts. Comprehensive metrics, including detection probability, latency, and resource efficiency, validate its efficacy under real-world conditions. Through its modular architecture, the framework achieves seamless integration with existing cybersecurity infrastructures without significant reconfiguration. The results demonstrate its robustness and scalability, offering a transformative paradigm for ransomware identification in dynamic and resource-constrained environments.


AnyNav: Visual Neuro-Symbolic Friction Learning for Off-road Navigation

arXiv.org Artificial Intelligence

Off-road navigation is essential for a wide range of applications in field robotics such as planetary exploration and disaster response. However, it remains an unresolved challenge due to the unstructured environments and inherent complexity of terrain-vehicle interactions. Traditional physics-based methods struggle to accurately model the nonlinear dynamics of these interactions, while data-driven approaches often suffer from overfitting to specific motion patterns, vehicle sizes, and types, limiting their generalizability. To overcome these challenges, we introduce a vision-based friction estimation framework grounded in neuro-symbolic principles, integrating neural networks for visual perception with symbolic reasoning for physical modeling. This enables significantly improved generalization abilities through explicit physical reasoning incorporating the predicted friction. Additionally, we develop a physics-informed planner that leverages the learned friction coefficient to generate physically feasible and efficient paths, along with corresponding speed profiles. We refer to our approach as AnyNav and evaluate it in both simulation and real-world experiments, demonstrating its utility and robustness across various off-road scenarios and multiple types of four-wheeled vehicles. These results mark an important step toward developing neuro-symbolic spatial intelligence to reason about complex, unstructured environments and enable autonomous off-road navigation in challenging scenarios. Video demonstrations are available at https://sairlab.org/anynav/, where the source code will also be released.


Deep Learning-Based Image Recovery and Pose Estimation for Resident Space Objects

arXiv.org Artificial Intelligence

As the density of spacecraft in Earth's orbit increases, their recognition, pose and trajectory identification becomes crucial for averting potential collisions and executing debris removal operations. However, training models able to identify a spacecraft and its pose presents a significant challenge due to a lack of available image data for model training. This paper puts forth an innovative framework for generating realistic synthetic datasets of Resident Space Object (RSO) imagery. Using the International Space Station (ISS) as a test case, it goes on to combine image regression with image restoration methodologies to estimate pose from blurred images. An analysis of the proposed image recovery and regression techniques was undertaken, providing insights into the performance, potential enhancements and limitations when applied to real imagery of RSOs. The image recovery approach investigated involves first applying image deconvolution using an effective point spread function, followed by detail object extraction with a U-Net. Interestingly, using only U-Net for image reconstruction the best pose performance was attained, reducing the average Mean Squared Error in image recovery by 97.28% and the average angular error by 71.9%. The successful application of U-Net image restoration combined with the Resnet50 regression network for pose estimation of the International Space Station demonstrates the value of a diverse set of evaluation tools for effective solutions to real-world problems such as the analysis of distant objects in Earth's orbit.


Watching the AI Watchdogs: A Fairness and Robustness Analysis of AI Safety Moderation Classifiers

arXiv.org Artificial Intelligence

AI Safety Moderation (ASM) classifiers are designed to moderate content on social media platforms and to serve as guardrails that prevent Large Language Models (LLMs) from being fine-tuned on unsafe inputs. Owing to their potential for disparate impact, it is crucial to ensure that these classifiers: (1) do not unfairly classify content belonging to users from minority groups as unsafe compared to those from majority groups and (2) that their behavior remains robust and consistent across similar inputs. In this work, we thus examine the fairness and robustness of four widely-used, closed-source ASM classifiers: OpenAI Moderation API, Perspective API, Google Cloud Natural Language (GCNL) API, and Clarifai API. We assess fairness using metrics such as demographic parity and conditional statistical parity, comparing their performance against ASM models and a fair-only baseline. Additionally, we analyze robustness by testing the classifiers' sensitivity to small and natural input perturbations. Our findings reveal potential fairness and robustness gaps, highlighting the need to mitigate these issues in future versions of these models.


To Measure or Not: A Cost-Sensitive, Selective Measuring Environment for Agricultural Management Decisions with Reinforcement Learning

arXiv.org Artificial Intelligence

Farmers rely on in-field observations to make well-informed crop management decisions to maximize profit and minimize adverse environmental impact. However, obtaining real-world crop state measurements is labor-intensive, time-consuming and expensive. In most cases, it is not feasible to gather crop state measurements before every decision moment. Moreover, in previous research pertaining to farm management optimization, these observations are often assumed to be readily available without any cost, which is unrealistic. Hence, enabling optimization without the need to have temporally complete crop state observations is important. An approach to that problem is to include measuring as part of decision making. As a solution, we apply reinforcement learning (RL) to recommend opportune moments to simultaneously measure crop features and apply nitrogen fertilizer. With realistic considerations, we design an RL environment with explicit crop feature measuring costs. While balancing costs, we find that an RL agent, trained with recurrent PPO, discovers adaptive measuring policies that follow critical crop development stages, with results aligned by what domain experts would consider a sensible approach. Our results highlight the importance of measuring when crop feature measurements are not readily available.


Provably-Safe Neural Network Training Using Hybrid Zonotope Reachability Analysis

arXiv.org Artificial Intelligence

Even though neural networks are being increasingly deployed in safety-critical applications, it remains difficult to enforce constraints on their output, meaning that it is hard to guarantee safety in such settings. Towards addressing this, many existing methods seek to verify a neural network's satisfaction of safety constraints, but do not address how to correct an "unsafe" network. On the other hand, the few works that extract a training signal from verification cannot handle non-convex sets, and are either conservative or slow. To address these challenges, this work proposes a neural network training method that can encourage the exact reachable set of a non-convex input set through a neural network with rectified linear unit (ReLU) nonlinearities to avoid a non-convex unsafe region, using recent results in non-convex set representation with hybrid zonotopes and extracting gradient information from mixed-integer linear programs (MILPs). The proposed method is fast, with the computational complexity of each training iteration comparable to that of solving a linear program (LP) with number of dimensions and constraints linear to the number of neurons and complexity of input and unsafe sets. For a neural network with three hidden layers of width 30, the method was able to drive the reachable set of a non-convex input set with 55 generators and 26 constraints out of a non-convex unsafe region with 21 generators and 11 constraints in 490 seconds.


Which Optimizer Works Best for Physics-Informed Neural Networks and Kolmogorov-Arnold Networks?

arXiv.org Artificial Intelligence

Physics-Informed Neural Networks (PINNs) have revolutionized the computation of PDE solutions by integrating partial differential equations (PDEs) into the neural network's training process as soft constraints, becoming an important component of the scientific machine learning (SciML) ecosystem. In its current implementation, PINNs are mainly optimized using first-order methods like Adam, as well as quasi-Newton methods such as BFGS and its low-memory variant, L-BFGS. However, these optimizers often struggle with highly non-linear and non-convex loss landscapes, leading to challenges such as slow convergence, local minima entrapment, and (non)degenerate saddle points. In this study, we investigate the performance of Self-Scaled Broyden (SSBroyden) methods and other advanced quasi-Newton schemes, including BFGS and L-BFGS with different line search strategies approaches. These methods dynamically rescale updates based on historical gradient information, thus enhancing training efficiency and accuracy. We systematically compare these optimizers on key challenging linear, stiff, multi-scale and non-linear PDEs benchmarks, including the Burgers, Allen-Cahn, Kuramoto-Sivashinsky, and Ginzburg-Landau equations, and extend our study to Physics-Informed Kolmogorov-Arnold Networks (PIKANs) representation. Our findings provide insights into the effectiveness of second-order optimization strategies in improving the convergence and accurate generalization of PINNs for complex PDEs by orders of magnitude compared to the state-of-the-art.


It's complicated. The relationship of algorithmic fairness and non-discrimination regulations in the EU AI Act

arXiv.org Artificial Intelligence

What constitutes a fair decision? This question is not only difficult for humans but becomes more challenging when Artificial Intelligence (AI) models are used. In light of discriminatory algorithmic behaviors, the EU has recently passed the AI Act, which mandates specific rules for AI models, incorporating both traditional legal non-discrimination regulations and machine learning based algorithmic fairness concepts. This paper aims to bridge these two different concepts in the AI Act through: First a high-level introduction of both concepts targeting legal and computer science-oriented scholars, and second an in-depth analysis of the AI Act's relationship between legal non-discrimination regulations and algorithmic fairness. Our analysis reveals three key findings: (1.), most non-discrimination regulations target only high-risk AI systems. (2.), the regulation of high-risk systems encompasses both data input requirements and output monitoring, though these regulations are often inconsistent and raise questions of computational feasibility. (3.) Regulations for General Purpose AI Models, such as Large Language Models that are not simultaneously classified as high-risk systems, currently lack specificity compared to other regulations. Based on these findings, we recommend developing more specific auditing and testing methodologies for AI systems. This paper aims to serve as a foundation for future interdisciplinary collaboration between legal scholars and computer science-oriented machine learning researchers studying discrimination in AI systems.