In this paper, we consider the problem of path finding for a set of homogeneous and autonomous agents navigating a previously unknown stochastic environment. In our problem setting, each agent attempts to maximize a given utility function while respecting safety properties. Our solution is based on ideas from evolutionary game theory, namely replicating policies that perform well and diminishing ones that do not. We do a comprehensive comparison with related multiagent planning methods, and show that our technique beats state of the art RL algorithms in minimizing path length by nearly 30% in large spaces. We show that our algorithm is computationally faster than deep RL methods by at least an order of magnitude. We also show that it scales better with an increase in the number of agents as compared to other methods, path planning methods in particular. Lastly, we empirically prove that the policies that we learn are evolutionarily stable and thus impervious to invasion by any other policy.

自然语言是人类将任务传达给机器人的直觉方式。尽管自然语言（NL）是模棱两可的，但现实世界的任务及其安全要求需要明确传达。信号时间逻辑（STL）是一种形式的逻辑，可以用作描述机器人任务的多功能，表达和明确的形式语言。一方面，使用STL用于机器人域的现有工作通常要求最终用户在STL中表达任务规格，这是非专家用户的挑战。另一方面，从NL转换为STL规范的转换限制为特定片段。在这项工作中，我们提出了Dialoguestl，这是一种从（通常）模棱两可的NL描述中学习正确和简洁的STL公式的交互方法。我们结合了语义解析，基于预训练的变压器的语言模型以及少数用户演示的用户澄清，以预测编码NL任务描述的最佳STL公式。将NL映射到STL的一个优点是，在使用增强学习（RL）以识别机器人的控制策略方面，最近有很多工作。我们表明，我们可以使用深层学习技术来从学习的STL规范中学习最佳策略。我们证明DialogUestl具有高效，可扩展性和健壮性，并且在预测正确的STL公式方面具有很高的精度，并与Oracle用户进行了一些演示和一些交互。

自动化车辆（AV）在很大程度上取决于强大的感知系统。评估视觉系统的当前方法主要关注逐帧性能。当在AV中使用时，这种评估方法似乎不足以评估感知子系统的性能。在本文中，我们提出了一种逻辑（称为时空感知逻辑（STPL）），该逻辑同时使用了空间和时间方式。STPL可以使用空间和时间关系来实现对感知数据的推理。STPL的一个主要优点是，即使在某些情况下没有地面真相数据，它也可以促进感知系统实时性能的基本理智检查。我们确定了STPL的片段，该片段是在多项式时间内有效地监视离线的。最后，我们提供了一系列针对AV感知系统的规格，以突出显示可以通过STPL通过离线监控来表达和分析的要求类型。

In the learning from demonstration (LfD) paradigm, understanding and evaluating the demonstrated behaviors plays a critical role in extracting control policies for robots. Without this knowledge, a robot may infer incorrect reward functions that lead to undesirable or unsafe control policies. Recent work has proposed an LfD framework where a user provides a set of formal task specifications to guide LfD, to address the challenge of reward shaping. However, in this framework, specifications are manually ordered in a performance graph (a partial order that specifies relative importance between the specifications). The main contribution of this paper is an algorithm to learn the performance graph directly from the user-provided demonstrations, and show that the reward functions generated using the learned performance graph generate similar policies to those from manually specified performance graphs. We perform a user study that shows that priorities specified by users on behaviors in a simulated highway driving domain match the automatically inferred performance graph. This establishes that we can accurately evaluate user demonstrations with respect to task specifications without expert criteria.

许多智能交通系统是多种代理系统，即交​​通参与者和运输基础设施内的子系统都可以被建模为互动代理。使用基于AI的方法在不同的代理系统之间实现协调可以提供更好的安全系统，这些运输系统仅包含人类操作车辆的运输系统，并在交通吞吐量，传感范围和启用协作任务方面提高系统效率。然而，增加的自主权使运输基础设施容易受到损害的车辆代理或基础设施。本文通过将信托权限嵌入运输基础设施来系统地量化称为主观逻辑的认知逻辑来系统地量化代理商的可信度来提出新的框架。在本文中，我们提出了以下新的贡献：（i）我们提出了一个框架，以利用代理商的量化可靠性来实现信任感知的协调和控制。 （ii）我们展示如何使用基于强化学习的方法来综合信任感知控制器。 （iii）我们全面分析了自主交叉口管理（AIM）案例研究，并制定了一个名为AIM-Trust的信任知识版本，导致在由可信和不受信任的代理商的混合中的情景中导致事故率降低。

In this paper we explore the task of modeling (semi) structured object sequences; in particular we focus our attention on the problem of developing a structure-aware input representation for such sequences. In such sequences, we assume that each structured object is represented by a set of key-value pairs which encode the attributes of the structured object. Given a universe of keys, a sequence of structured objects can then be viewed as an evolution of the values for each key, over time. We encode and construct a sequential representation using the values for a particular key (Temporal Value Modeling - TVM) and then self-attend over the set of key-conditioned value sequences to a create a representation of the structured object sequence (Key Aggregation - KA). We pre-train and fine-tune the two components independently and present an innovative training schedule that interleaves the training of both modules with shared attention heads. We find that this iterative two part-training results in better performance than a unified network with hierarchical encoding as well as over, other methods that use a {\em record-view} representation of the sequence \cite{de2021transformers4rec} or a simple {\em flattened} representation of the sequence. We conduct experiments using real-world data to demonstrate the advantage of interleaving TVM-KA on multiple tasks and detailed ablation studies motivating our modeling choices. We find that our approach performs better than flattening sequence objects and also allows us to operate on significantly larger sequences than existing methods.

Optical coherence tomography (OCT) captures cross-sectional data and is used for the screening, monitoring, and treatment planning of retinal diseases. Technological developments to increase the speed of acquisition often results in systems with a narrower spectral bandwidth, and hence a lower axial resolution. Traditionally, image-processing-based techniques have been utilized to reconstruct subsampled OCT data and more recently, deep-learning-based methods have been explored. In this study, we simulate reduced axial scan (A-scan) resolution by Gaussian windowing in the spectral domain and investigate the use of a learning-based approach for image feature reconstruction. In anticipation of the reduced resolution that accompanies wide-field OCT systems, we build upon super-resolution techniques to explore methods to better aid clinicians in their decision-making to improve patient outcomes, by reconstructing lost features using a pixel-to-pixel approach with an altered super-resolution generative adversarial network (SRGAN) architecture.

Real-life tools for decision-making in many critical domains are based on ranking results. With the increasing awareness of algorithmic fairness, recent works have presented measures for fairness in ranking. Many of those definitions consider the representation of different ``protected groups'', in the top-$k$ ranked items, for any reasonable $k$. Given the protected groups, confirming algorithmic fairness is a simple task. However, the groups' definitions may be unknown in advance. In this paper, we study the problem of detecting groups with biased representation in the top-$k$ ranked items, eliminating the need to pre-define protected groups. The number of such groups possible can be exponential, making the problem hard. We propose efficient search algorithms for two different fairness measures: global representation bounds, and proportional representation. Then we propose a method to explain the bias in the representations of groups utilizing the notion of Shapley values. We conclude with an experimental study, showing the scalability of our approach and demonstrating the usefulness of the proposed algorithms.

The previous fine-grained datasets mainly focus on classification and are often captured in a controlled setup, with the camera focusing on the objects. We introduce the first Fine-Grained Vehicle Detection (FGVD) dataset in the wild, captured from a moving camera mounted on a car. It contains 5502 scene images with 210 unique fine-grained labels of multiple vehicle types organized in a three-level hierarchy. While previous classification datasets also include makes for different kinds of cars, the FGVD dataset introduces new class labels for categorizing two-wheelers, autorickshaws, and trucks. The FGVD dataset is challenging as it has vehicles in complex traffic scenarios with intra-class and inter-class variations in types, scale, pose, occlusion, and lighting conditions. The current object detectors like yolov5 and faster RCNN perform poorly on our dataset due to a lack of hierarchical modeling. Along with providing baseline results for existing object detectors on FGVD Dataset, we also present the results of a combination of an existing detector and the recent Hierarchical Residual Network (HRN) classifier for the FGVD task. Finally, we show that FGVD vehicle images are the most challenging to classify among the fine-grained datasets.

Three main points: 1. Data Science (DS) will be increasingly important to heliophysics; 2. Methods of heliophysics science discovery will continually evolve, requiring the use of learning technologies [e.g., machine learning (ML)] that are applied rigorously and that are capable of supporting discovery; and 3. To grow with the pace of data, technology, and workforce changes, heliophysics requires a new approach to the representation of knowledge.