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Software Reconfiguration in Robotics

arXiv.org Artificial Intelligence

Since it has often been claimed by academics that reconfiguration is essential, many approaches to reconfiguration, especially of robotic systems, have been developed. Accordingly, the literature on robotics is rich in techniques for reconfiguring robotic systems. However, when talking to researchers in the domain, there seems to be no common understanding of what exactly reconfiguration is and how it relates to other concepts such as adaptation. Beyond this academic perspective, robotics frameworks provide mechanisms for dynamically loading and unloading parts of robotics applications. While we have a fuzzy picture of the state-of-the-art in robotic reconfiguration from an academic perspective, we lack a picture of the state-of-practice from a practitioner perspective. To fill this gap, we survey the literature on reconfiguration in robotic systems by identifying and analyzing 98 relevant papers, review how four major robotics frameworks support reconfiguration, and finally investigate the realization of reconfiguration in 48 robotics applications. When comparing the state-of-the-art with the state-of-practice, we observed a significant discrepancy between them, in particular, the scientific community focuses on complex structural reconfiguration, while in practice only parameter reconfiguration is widely used. Based on our observations, we discuss possible reasons for this discrepancy and conclude with a takeaway message for academics and practitioners interested in robotics.


SEA: Sparse Linear Attention with Estimated Attention Mask

arXiv.org Artificial Intelligence

The transformer architecture has made breakthroughs in recent years on tasks which require modeling pairwise relationships between sequential elements, as is the case in natural language understanding. However, transformers struggle with long sequences due to the quadratic complexity of the attention operation, and previous research has aimed to lower the complexity by sparsifying or linearly approximating the attention matrix. Yet, these approaches cannot straightforwardly distill knowledge from a teacher's attention matrix, and often require complete retraining from scratch. Furthermore, previous sparse and linear approaches may also lose interpretability if they do not produce full quadratic attention matrices. To address these challenges, we propose SEA: Sparse linear attention with an Estimated Attention mask. SEA estimates the attention matrix with linear complexity via kernel-based linear attention, then creates a sparse approximation to the full attention matrix with a top-k selection to perform a sparse attention operation. For language modeling tasks (Wikitext2), previous linear and sparse attention methods show a roughly two-fold worse perplexity scores over the quadratic OPT-125M baseline, while SEA achieves an even better perplexity than OPT-125M, using roughly half as much memory as OPT-125M. Moreover, SEA maintains an interpretable attention matrix and can utilize knowledge distillation to lower the complexity of existing pretrained transformers. We believe that our work will have a large practical impact, as it opens the possibility of running large transformers on resource-limited devices with less memory.


Fool Your (Vision and) Language Model With Embarrassingly Simple Permutations

arXiv.org Artificial Intelligence

Large language and vision-language models are rapidly being deployed in practice thanks to their impressive capabilities in instruction following, in-context learning, and so on. This raises an urgent need to carefully analyse their robustness so that stakeholders can understand if and when such models are trustworthy enough to be relied upon in any given application. In this paper, we highlight a specific vulnerability in popular models, namely permutation sensitivity in multiple-choice question answering (MCQA). Specifically, we show empirically that popular models are vulnerable to adversarial permutation in answer sets for multiple-choice prompting, which is surprising as models should ideally be as invariant to prompt permutation as humans are. These vulnerabilities persist across various model sizes, and exist in very recent language and vision-language models. Code is available at \url{https://github.com/ys-zong/FoolyourVLLMs}.


Exploring Naming Conventions (and Defects) of Pre-trained Deep Learning Models in Hugging Face and Other Model Hubs

arXiv.org Artificial Intelligence

As innovation in deep learning continues, many engineers want to adopt Pre-Trained deep learning Models (PTMs) as components in computer systems. PTMs are part of a research-to-practice pipeline: researchers publish PTMs, which engineers adapt for quality or performance and then deploy. If PTM authors choose appropriate names for their PTMs, it could facilitate model discovery and reuse. However, prior research has reported that model names are not always well chosen, and are sometimes erroneous. The naming conventions and naming defects for PTM packages have not been systematically studied - understanding them will add to our knowledge of how the research-to-practice process works for PTM packages In this paper, we report the first study of PTM naming conventions and the associated PTM naming defects. We define the components of a PTM package name, comprising the package name and claimed architecture from the metadata. We present the first study focused on characterizing the nature of naming in PTM ecosystem. To this end, we developed a novel automated naming assessment technique that can automatically extract the semantic and syntactic patterns. To identify potential naming defects, we developed a novel algorithm, automated DNN ARchitecture Assessment pipeline (DARA), to cluster PTMs based on architectural differences. Our study suggests the naming conventions for PTMs, and frames the naming conventions as signal of the research-to-practice relationships in the PTM ecosystem. We envision future works on further empirical study on leveraging meta-features of PTMs to support model search and reuse.


VAL: Interactive Task Learning with GPT Dialog Parsing

arXiv.org Artificial Intelligence

Reinforcement learning often requires millions of examples to produce static, black-box models. In contrast, interactive task learning (ITL) emphasizes incremental knowledge acquisition from limited instruction provided by humans in modalities such as natural language. However, in practice, ITL systems often suffers from brittle, error-prone language parsing. Large language models (LLMs) are resistant to brittleness but are not interpretable and cannot learn incrementally. We present VAL, an ITL system with a new philosophy for LLM/symbolic integration. By using LLMs only for specific tasks -- such as predicate and argument selection -- within an algorithmic framework, VAL reaps the benefits of LLMs to support interactive learning of hierarchical task knowledge from natural language. Acquired knowledge is human interpretable and generalizes to support execution of novel tasks without additional training. We studied users' interactions with VAL in a video game setting, finding that most users could successfully teach VAL using language they felt was natural.


Causality-informed Rapid Post-hurricane Building Damage Detection in Large Scale from InSAR Imagery

arXiv.org Artificial Intelligence

Timely and accurate assessment of hurricane-induced building damage is crucial for effective post-hurricane response and recovery efforts. Recently, remote sensing technologies provide large-scale optical or Interferometric Synthetic Aperture Radar (InSAR) imagery data immediately after a disastrous event, which can be readily used to conduct rapid building damage assessment. Compared to optical satellite imageries, the Synthetic Aperture Radar can penetrate cloud cover and provide more complete spatial coverage of damaged zones in various weather conditions. However, these InSAR imageries often contain highly noisy and mixed signals induced by co-occurring or co-located building damage, flood, flood/wind-induced vegetation changes, as well as anthropogenic activities, making it challenging to extract accurate building damage information. In this paper, we introduced an approach for rapid post-hurricane building damage detection from InSAR imagery. This approach encoded complex causal dependencies among wind, flood, building damage, and InSAR imagery using a holistic causal Bayesian network. Based on the causal Bayesian network, we further jointly inferred the large-scale unobserved building damage by fusing the information from InSAR imagery with prior physical models of flood and wind, without the need for ground truth labels. Furthermore, we validated our estimation results in a real-world devastating hurricane -- the 2022 Hurricane Ian. We gathered and annotated building damage ground truth data in Lee County, Florida, and compared the introduced method's estimation results with the ground truth and benchmarked it against state-of-the-art models to assess the effectiveness of our proposed method. Results show that our method achieves rapid and accurate detection of building damage, with significantly reduced processing time compared to traditional manual inspection methods.


A Good Snowman is Hard to Plan

arXiv.org Artificial Intelligence

In this work we face a challenging puzzle video game: A Good Snowman is Hard to Build. The objective of the game is to build snowmen by moving and stacking snowballs on a discrete grid. For the sake of player engagement with the game, it is interesting to avoid that a player finds a much easier solution than the one the designer expected. Therefore, having tools that are able to certify the optimality of solutions is crucial. Although the game can be stated as a planning problem and can be naturally modelled in PDDL, we show that a direct translation to SAT clearly outperforms off-the-shelf state-of-the-art planners. As we show, this is mainly due to the fact that reachability properties can be easily modelled in SAT, allowing for shorter plans, whereas using axioms to express a reachability derived predicate in PDDL does not result in any significant reduction of solving time with the considered planners. We deal with a set of 51 levels, both original and crafted, solving 43 and with 8 challenging instances still remaining to be solved.


On Grid Graph Reachability and Puzzle Games

arXiv.org Artificial Intelligence

Many puzzle video games, like Sokoban, involve moving some agent in a maze. The reachable locations are usually apparent for a human player, and the difficulty of the game is mainly related to performing actions on objects, such as pushing (reachable) boxes. For this reason, the difficulty of a particular level is often measured as the number of actions on objects, other than agent walking, needed to find a solution. In this paper we study CP and SAT approaches for solving these kind of problems. We review some reachability encodings and propose a new one. We empirically show that the new encoding is well-suited for solving puzzle problems in the planning as SAT paradigm, especially when considering the execution of several actions in parallel.


UltraFeedback: Boosting Language Models with High-quality Feedback

arXiv.org Artificial Intelligence

Reinforcement learning from human feedback (RLHF) has become a pivot technique in aligning large language models (LLMs) with human preferences. In RLHF practice, preference data plays a crucial role in bridging human proclivity and LLMs. However, the scarcity of diverse, naturalistic datasets of human preferences on LLM outputs at scale poses a great challenge to RLHF as well as feedback learning research within the open-source community. Current preference datasets, either proprietary or limited in size and prompt variety, result in limited RLHF adoption in open-source models and hinder further exploration. We meticulously devise annotation instructions and employ GPT-4 to offer detailed feedback in both numerical and textual forms. Experimental results indicate that our models outperform existing open-source models, achieving top performance across multiple benchmarks. Large language models (LLMs), represented by ChatGPT (OpenAI, 2022) and GPT-4 (OpenAI, 2023), have demonstrated proficiency in generating fluent text as well as solving various languageoriented tasks. Trained on massive corpora through likelihood maximization techniques, these LLMs have exhibited remarkable generalization and equipped the ability to execute diverse tasks in response to user directives (Ouyang et al., 2022; Wei et al., 2022; Sanh et al., 2022). Unfortunately, relying solely on likelihood maximization during training leads to well-known issues - LLMs may generate convincing but incorrect or unsafe content that deviates from human preferences (Stiennon et al., 2020; Ouyang et al., 2022; Perez et al., 2022). To further align LLMs with human preferences, reinforcement learning from human feedback (RLHF) (Ouyang et al., 2022; Askell et al., 2021; Bai et al., 2022a; Touvron et al., 2023b) has been introduced and widely adopted by leading corporations. RLHF builds upon preference data, which rates and compares different responses given the same prompt. Typically, RLHF trains a reward model on preference data and then applies RL algorithms such as Proximal Policy Optimization (PPO) (Schulman et al., 2017) on LLMs to optimize the rewards (OpenAI, 2022; 2023; Touvron et al., 2023b; Bai et al., 2022a). While proprietary models have largely capitalized on RLHF's potential to produce outputs that are both more useful and safer, a significant gap persists in the open-source community. As a result, few open-source models adopt RLHF as it demonstrates marginal gains, which critically hinders successful RLHF practice and further research.


RRR-Net: Reusing, Reducing, and Recycling a Deep Backbone Network

arXiv.org Artificial Intelligence

It has become mainstream in computer vision and other machine learning domains to reuse backbone networks pre-trained on large datasets as preprocessors. Typically, the last layer is replaced by a shallow learning machine of sorts; the newly-added classification head and (optionally) deeper layers are fine-tuned on a new task. Due to its strong performance and simplicity, a common pre-trained backbone network is ResNet152.However, ResNet152 is relatively large and induces inference latency. In many cases, a compact and efficient backbone with similar performance would be preferable over a larger, slower one. This paper investigates techniques to reuse a pre-trained backbone with the objective of creating a smaller and faster model. Starting from a large ResNet152 backbone pre-trained on ImageNet, we first reduce it from 51 blocks to 5 blocks, reducing its number of parameters and FLOPs by more than 6 times, without significant performance degradation. Then, we split the model after 3 blocks into several branches, while preserving the same number of parameters and FLOPs, to create an ensemble of sub-networks to improve performance. Our experiments on a large benchmark of $40$ image classification datasets from various domains suggest that our techniques match the performance (if not better) of ``classical backbone fine-tuning'' while achieving a smaller model size and faster inference speed.