Offline reinforcement-learning (RL) algorithms learn to make decisions using a given, fixed training dataset without the possibility of additional online data collection. This problem setting is captivating because it holds the promise of utilizing previously collected datasets without any costly or risky interaction with the environment. However, this promise also bears the drawback of this setting. The restricted dataset induces subjective uncertainty because the agent can encounter unfamiliar sequences of states and actions that the training data did not cover. Moreover, inherent system stochasticity further increases uncertainty and aggravates the offline RL problem, preventing the agent from learning an optimal policy. To mitigate the destructive uncertainty effects, we need to balance the aspiration to take reward-maximizing actions with the incurred risk due to incorrect ones. In financial economics, modern portfolio theory (MPT) is a method that risk-averse investors can use to construct diversified portfolios that maximize their returns without unacceptable levels of risk. We integrate MPT into the agent's decision-making process to present a simple-yet-highly-effective risk-aware planning algorithm for offline RL. Our algorithm allows us to systematically account for the \emph{estimated quality} of specific actions and their \emph{estimated risk} due to the uncertainty. We show that our approach can be coupled with the Transformer architecture to yield a state-of-the-art planner for offline RL tasks, maximizing the return while significantly reducing the variance.

建立机器人假体的核心挑战是创建基于传感器的系统，能够从下肢读取生理信号，并指示机器人手执行各种任务。现有系统通常通过采用肌电图（EMG）或超声（US）技术来分析肌肉状态，进行诸如指向或抓握之类的离散手势。虽然过去通过检测突出的手势来估算手势手势，但我们对检测或推理感兴趣，在随着时间的流逝而发展的精细运动的背景下进行。示例包括执行精细且灵巧的任务（例如键盘打字或钢琴弹奏）时发生的动作。我们将这项任务视为朝着臂截肢者中机器人假体提高采用率的重要一步，因为它有可能显着提高执行日常任务的功能。为此，我们提出了一个端到端的机器人系统，可以成功推断出精细的手指运动。这是通过将手作为机器人操纵器建模并将其用作中间表示来实现的，以从美国图像序列中编码肌肉的动力学。我们通过收集一组主题的数据来评估我们的方法，并演示如何使用它来重播播放或键入文字。据我们所知，这是第一个研究端到端系统中这些下游任务的第一项研究。

自主无人驾驶飞行器（无人机）的重要能力是自动降落，同时避免在该过程中碰撞障碍。这种能力需要实时局部轨迹规划。虽然已经引入了轨迹规划方法，但在紧急登陆等案件中，它们尚未在现实生活场景中进行评估，其中只能感测和检测到障碍物表面。我们使用预先计划的全局路径和着陆区域的优先级地图提出了一种新颖的优化框架。在包括3D城市环境，基于LIDAR的障碍 - 表面感应和UAV指导和动态的模拟器中实施和评估了多个轨迹规划算法。我们表明，使用我们所提出的优化标准可以成功提高着陆关联成功概率，同时避免实时与障碍物的碰撞。

Steerable needles are capable of accurately targeting difficult-to-reach clinical sites in the body. By bending around sensitive anatomical structures, steerable needles have the potential to reduce the invasiveness of many medical procedures. However, inserting these needles with curved trajectories increases the risk of tissue damage due to perpendicular forces exerted on the surrounding tissue by the needle's shaft, potentially resulting in lateral shearing through tissue. Such forces can cause significant damage to surrounding tissue, negatively affecting patient outcomes. In this work, we derive a tissue and needle force model based on a Cosserat string formulation, which describes the normal forces and frictional forces along the shaft as a function of the planned needle path, friction model and parameters, and tip piercing force. We propose this new force model and associated cost function as a safer and more clinically relevant metric than those currently used in motion planning for steerable needles. We fit and validate our model through physical needle robot experiments in a gel phantom. We use this force model to define a bottleneck cost function for motion planning and evaluate it against the commonly used path-length cost function in hundreds of randomly generated 3-D environments. Plans generated with our force-based cost show a 62% reduction in the peak modeled tissue force with only a 0.07% increase in length on average compared to using the path-length cost in planning. Additionally, we demonstrate the ability to plan motions with our force-based cost function in a lung tumor biopsy scenario from a segmented computed tomography (CT) scan. By planning motions for the needle that aim to minimize the modeled needle-to-tissue force explicitly, our method plans needle paths that may reduce the risk of significant tissue damage while still reaching desired targets in the body.

Key Point Analysis(KPA) is a relatively new task in NLP that combines summarization and classification by extracting argumentative key points (KPs) for a topic from a collection of texts and categorizing their closeness to the different arguments. In our work, we focus on the legal domain and develop methods that identify and extract KPs from premises derived from texts of judgments. The first method is an adaptation to an existing state-of-the-art method, and the two others are new methods that we developed from scratch. We present our methods and examples of their outputs, as well a comparison between them. The full evaluation of our results is done in the matching task -- match between the generated KPs to arguments (premises).

A gradual semantics takes a weighted argumentation framework as input and outputs a final acceptability degree for each argument, with different semantics performing the computation in different manners. In this work, we consider the problem of attack inference. That is, given a gradual semantics, a set of arguments with associated initial weights, and the final desirable acceptability degrees associated with each argument, we seek to determine whether there is a set of attacks on those arguments such that we can obtain these acceptability degrees. The main contribution of our work is to demonstrate that the associated decision problem, i.e., whether a set of attacks can exist which allows the final acceptability degrees to occur for given initial weights, is NP-complete for the weighted h-categoriser and cardinality-based semantics, and is polynomial for the weighted max-based semantics, even for the complete version of the problem (where all initial weights and final acceptability degrees are known). We then briefly discuss how this decision problem can be modified to find the attacks themselves and conclude by examining the partial problem where not all initial weights or final acceptability degrees may be known.

Given a symmetric matrix $M$ and a vector $\lambda$, we present new bounds on the Frobenius-distance utility of the Gaussian mechanism for approximating $M$ by a matrix whose spectrum is $\lambda$, under $(\varepsilon,\delta)$-differential privacy. Our bounds depend on both $\lambda$ and the gaps in the eigenvalues of $M$, and hold whenever the top $k+1$ eigenvalues of $M$ have sufficiently large gaps. When applied to the problems of private rank-$k$ covariance matrix approximation and subspace recovery, our bounds yield improvements over previous bounds. Our bounds are obtained by viewing the addition of Gaussian noise as a continuous-time matrix Brownian motion. This viewpoint allows us to track the evolution of eigenvalues and eigenvectors of the matrix, which are governed by stochastic differential equations discovered by Dyson. These equations allow us to bound the utility as the square-root of a sum-of-squares of perturbations to the eigenvectors, as opposed to a sum of perturbation bounds obtained via Davis-Kahan-type theorems.

最近的几种方法，例如参数有效的微调（PEFT）和模式开发训练（PET），在标签筛选设置中取得了令人印象深刻的结果。但是，它们很难使用，因为它们会受到手动制作的提示的高度可变性，并且通常需要十亿参数语言模型才能达到高精度。为了解决这些缺点，我们提出了SETFIT（句子变压器微调），这是一个有效且迅速的框架，用于对句子变形金刚（ST）进行几次微调。 SetFit首先以对比的暹罗方式对少数文本对进行微调验证的st。然后将所得模型用于生成丰富的文本嵌入，这些嵌入方式用于训练分类头。这个简单的框架不需要任何提示或口头化，并且比现有技术少的参数较少，因此可以实现高精度。我们的实验表明，SetFit通过PEFT和PET技术获得了可比的结果，同时训练的速度更快。我们还表明，SETFIT可以通过简单地切换ST主体来应用于多语言设置。我们的代码可从https://github.com/huggingface/setFit以及我们的数据集获得，网址为https://huggingface.co/setfit。

我们建议第一个通过对弱的微型计算机进行深入学习的实时语义细分的系统，例如Raspberry Pi Zero Zero V2（其价格\ 15美元）附加到玩具无人机上。特别是，由于Raspberry Pi的重量不到$ 16 $，并且其大小是信用卡的一半，因此我们可以轻松地将其连接到普通的商业DJI Tello玩具器中（<\ $ 100，<90克，98 $ \ \时间$ 92.5 $ \ times $ 41毫米）。结果是可以从板载单眼RGB摄像头（无GPS或LIDAR传感器）实时检测和分类对象的自动无人机（无笔记本电脑或人类）。伴侣视频展示了这款Tello无人机如何扫描实验室的人（例如使用消防员或安全部队）以及在实验室外的空停车位。现有的深度学习解决方案要么在这种物联网设备上实时计算要么太慢，要么提供不切实际的质量结果。我们的主要挑战是设计一个系统，该系统在网络，深度学习平台/框架，压缩技术和压缩比的众多组合中占有最好的选择。为此，我们提供了一种有效的搜索算法，旨在找到最佳组合，从而导致网络运行时间与其准确性/性能之间的最佳权衡。

在视频分析中，背景模型具有许多应用，例如背景/前景分离，变更检测，异常检测，跟踪等。但是，尽管在静态相机捕获的视频中学习这种模型是一项公认的任务，但在移动相机背景模型（MCBM）的情况下，由于算法和可伸缩性挑战，成功率更加重要。由于相机运动而产生。因此，现有的MCBM在其范围和受支持的摄像头类型的限制中受到限制。这些障碍还阻碍了基于深度学习（DL）的端到端解决方案的这项无监督的任务。此外，现有的MCBM通常会在典型的大型全景图像或以在线方式的域名上建模背景。不幸的是，前者造成了几个问题，包括可扩展性差，而后者则阻止了对摄像机重新审视场景先前看到部分的案例的识别和利用。本文提出了一种称为DEEPMCBM的新方法，该方法消除了上述所有问题并实现最新结果。具体而言，首先，我们确定与一般和DL设置的视频帧联合对齐相关的困难。接下来，我们提出了一种新的联合一致性策略，使我们可以使用具有正则化的空间变压器网，也不是任何形式的专业化（且不差异）的初始化。再加上在不破坏的稳健中央矩（从关节对齐中获得）的自动编码器，这产生了一个无端到端的无端正规化MCBM，该MCBM支持广泛的摄像机运动并优雅地缩放。我们在各种视频上展示了DEEPMCBM的实用程序，包括超出其他方法范围的视频。我们的代码可在https://github.com/bgu-cs-vil/deepmcbm上找到。