Alomrani, Mohammad Ali
Mem2Ego: Empowering Vision-Language Models with Global-to-Ego Memory for Long-Horizon Embodied Navigation
Zhang, Lingfeng, Liu, Yuecheng, Zhang, Zhanguang, Aghaei, Matin, Hu, Yaochen, Gu, Hongjian, Alomrani, Mohammad Ali, Bravo, David Gamaliel Arcos, Karimi, Raika, Hamidizadeh, Atia, Xu, Haoping, Huang, Guowei, Zhang, Zhanpeng, Cao, Tongtong, Qiu, Weichao, Quan, Xingyue, Hao, Jianye, Zhuang, Yuzheng, Zhang, Yingxue
Recent advancements in Large Language Models (LLMs) and Vision-Language Models (VLMs) have made them powerful tools in embodied navigation, enabling agents to leverage commonsense and spatial reasoning for efficient exploration in unfamiliar environments. Existing LLM-based approaches convert global memory, such as semantic or topological maps, into language descriptions to guide navigation. While this improves efficiency and reduces redundant exploration, the loss of geometric information in language-based representations hinders spatial reasoning, especially in intricate environments. To address this, VLM-based approaches directly process ego-centric visual inputs to select optimal directions for exploration. However, relying solely on a first-person perspective makes navigation a partially observed decision-making problem, leading to suboptimal decisions in complex environments. In this paper, we present a novel vision-language model (VLM)-based navigation framework that addresses these challenges by adaptively retrieving task-relevant cues from a global memory module and integrating them with the agent's egocentric observations. By dynamically aligning global contextual information with local perception, our approach enhances spatial reasoning and decision-making in long-horizon tasks. Experimental results demonstrate that the proposed method surpasses previous state-of-the-art approaches in object navigation tasks, providing a more effective and scalable solution for embodied navigation.
Path-of-Thoughts: Extracting and Following Paths for Robust Relational Reasoning with Large Language Models
Zhang, Ge, Alomrani, Mohammad Ali, Gu, Hongjian, Zhou, Jiaming, Hu, Yaochen, Wang, Bin, Liu, Qun, Coates, Mark, Zhang, Yingxue, Hao, Jianye
Large language models (LLMs) possess vast semantic knowledge but often struggle with complex reasoning tasks, particularly in relational reasoning problems such as kinship or spatial reasoning. In this paper, we present Path-of-Thoughts (PoT), a novel framework designed to tackle relation reasoning by decomposing the task into three key stages: graph extraction, path identification, and reasoning. Unlike previous approaches, PoT efficiently extracts a task-agnostic graph that identifies crucial entities, relations, and attributes within the problem context. Subsequently, PoT identifies relevant reasoning chains within the graph corresponding to the posed question, facilitating inference of potential answers. Experimental evaluations on four benchmark datasets, demanding long reasoning chains, demonstrate that PoT surpasses state-of-the-art baselines by a significant margin (maximum 21.3%) without necessitating fine-tuning or extensive LLM calls. Furthermore, as opposed to prior neuro-symbolic methods, PoT exhibits improved resilience against LLM errors by leveraging the compositional nature of graphs.
DyG2Vec: Efficient Representation Learning for Dynamic Graphs
Alomrani, Mohammad Ali, Biparva, Mahdi, Zhang, Yingxue, Coates, Mark
Temporal graph neural networks have shown promising results in learning inductive representations by automatically extracting temporal patterns. However, previous works often rely on complex memory modules or inefficient random walk methods to construct temporal representations. To address these limitations, we present an efficient yet effective attention-based encoder that leverages temporal edge encodings and window-based subgraph sampling to generate task-agnostic embeddings. Moreover, we propose a joint-embedding architecture using non-contrastive SSL to learn rich temporal embeddings without labels. Experimental results on 7 benchmark datasets indicate that on average, our model outperforms SoTA baselines on the future link prediction task by 4.23% for the transductive setting and 3.30% for the inductive setting while only requiring 5-10x less training/inference time. Lastly, different aspects of the proposed framework are investigated through experimental analysis and ablation studies. The code is publicly available at https://github.com/huawei-noah/noah-research/tree/master/graph_atlas.
Deep Policies for Online Bipartite Matching: A Reinforcement Learning Approach
Alomrani, Mohammad Ali, Moravej, Reza, Khalil, Elias B.
From assigning computing tasks to servers and advertisements to users, sequential online matching problems arise in a wide variety of domains. The challenge in online matching lies in making irrevocable assignments while there is uncertainty about future inputs. In the theoretical computer science literature, most policies are myopic or greedy in nature. In real-world applications where the matching process is repeated on a regular basis, the underlying data distribution can be leveraged for better decision-making. We present an end-to-end Reinforcement Learning framework for deriving better matching policies based on trial-and-error on historical data. We devise a set of neural network architectures, design feature representations, and empirically evaluate them across two online matching problems: Edge-Weighted Online Bipartite Matching and Online Submodular Bipartite Matching. We show that most of the learning approaches perform significantly better than classical greedy algorithms on four synthetic and real-world datasets. Our code is publicly available at https://github.com/lyeskhalil/CORL.git.
A Critical Review of Information Bottleneck Theory and its Applications to Deep Learning
Alomrani, Mohammad Ali
In the past decade, deep neural networks have seen unparalleled improvements that continue to impact every aspect of today's society. With the development of high performance GPUs and the availability of vast amounts of data, learning capabilities of ML systems have skyrocketed, going from classifying digits in a picture to beating world-champions in games with super-human performance. However, even as ML models continue to achieve new frontiers, their practical success has been hindered by the lack of a deep theoretical understanding of their inner workings. Fortunately, a known information-theoretic method called the information bottleneck theory has emerged as a promising approach to better understand the learning dynamics of neural networks. In principle, IB theory models learning as a trade-off between the compression of the data and the retainment of information. The goal of this survey is to provide a comprehensive review of IB theory covering it's information theoretic roots and the recently proposed applications to understand deep learning models.