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The increasing deployment of robots alongside humans necessitates sophisticated communication and motion planning to ensure safety and task achievability in social navigation scenarios. Existing methods often rely heavily on historical data and extensive expert hand-coding, which limits their scalability and generalizability. This paper introduces a novel framework that models social navigation as a Markov Decision Process (MDP), utilizing Conditional Abstraction Trees (CATs) to learn dynamic abstract world representations and policies that focus on critical aspects of interaction. In the offline phase, the framework operates within a simulator, while in the online phase, it deploys the learned representations and policies in real-world scenarios for ongoing refinement and adaptation. Integral to our approach is a Dynamic Bayesian Network (DBN) based human sensor and belief model that accounts for humans’ imperfect perception to enhance the prediction of human motion. We evaluated our method through extensive simulations and user studies involving physical experiments, demonstrating its effectiveness in managing critical interactions and ensuring safety and task completion across various scenarios. 

Log-Structured Merge-tree-based Key-Value Stores (LSM-KVS) are widely used to support modern, high-performance, data-intensive applications. In recent years, with the trend of deploying and optimizing LSM-KVS from monolith to Disaggregated Storage (DS) setups, the confidentiality of LSM-KVS persistent data (e.g., WAL and SST files) is vulnerable to unauthorized access from insiders and external attackers and must be protected using encryption. Existing solutions lack a high-performance design for encryption in LSM-KVS, often focus on in-memory data protection with overheads of 3.4-32.5x, and lack the scalability and flexibility considerations required in DS deployments. This paper proposes two novel designs to address the challenges of providing robust security for persistent components of LSM-KVS while maintaining high performance in both monolith and DS deployments - a simple and effective instance-level design suitable for monolithic LSM-KVS deployments, andSHIELD,a design that embeds encryption into LSM-KVS components for minimal overhead in both monolithic and DS deployment. We achieve our objective through three contributions: (1) A fine-grained integration of encryption into LSM-KVS write path to minimize performance overhead from exposure-limiting practices like using unique encryption keys per file and regularly re-encrypting using new encryption keys during compaction, (2) Mitigating performance degradation caused by recurring encryption of Write-Ahead Log (WAL) writes by using a buffering solution and (3) Extending confidentiality guarantees to DS by designing a metadata-enabled encryption-key-sharing mechanism and a secure local cache for high scalability and flexibility. We implement both designs on RocksDB, evaluating them in monolithic and DS setups while showcasing an overhead of 0-32% for the instance-level design and 0-36% for SHIELD. 

Large language models (LLMs) have achieved high accuracy in diverse NLP and computer vision tasks due to self- attention mechanisms relying on GEMM and GEMV operations. However, scaling LLMs poses significant computational and energy challenges, particularly for traditional Von-Neumann architectures (CPUs/GPUs), which incur high latency and energy consumption from frequent data movement. These issues are even more pronounced in energy-constrained edge environments. While DRAM-based near-memory architectures offer improved energy efficiency and throughput, their processing elements are limited by strict area, power, and timing constraints. This work introduces CIDAN-3D, a novel Processing-in-Memory (PIM) architecture tailored for LLMs. It features an ultra-low-power Neuron Processing Element (NPE) with high compute density (#Operations/Area), enabling ecient in-situ execution of LLM operations by leveraging high parallelism within DRAM. CIDAN- 3D reduces data movement, improves locality, and achieves substantial gains in performance and energy efficiency—showing up to 1.3X higher throughput and 21.9X better energy efficiency for smaller models, and 3X throughput and 7X energy improvement for large decoder-only models compared to prior near-memory designs. As a result, CIDAN-3D offers a scalable, energy-efficient platform for LLM-driven Gen-AI applications. 

Heterogeneous distributed systems, including the Internet of Things (IoT) or distributed cyber-physical systems (CPS), often su↵er a lack of interoperability and security, which hinders the wider deployment of such systems. Specifically, the di↵erent levels of security requirements and the heterogeneity in terms of communication models, for instance, point-to-point vs. publish-subscribe, are the example challenges of IoT and distributed CPS consisting of heterogeneous devices and applications. In this paper, we propose a working application programming interface (API) and runtime to enhance interoperability and security while addressing the challenges that stem from the heterogeneity in the IoT and distributed CPS. In our case study, we design and implement our application programming interface (API) design approach using opensource software, and with our working implementation, we evaluate the e↵ectiveness of our proposed approach. Our experimental results suggest that our approach can achieve both interoperability and security in the IoT and distributed CPS with a reasonably small overhead and better-managed software.