Diagnostic radiologists need artificial intelligence (AI) for medical imaging, but access to medical images required for training in AI has become increasingly restrictive. To release and use medical images, we need an algorithm that can simultaneously protect privacy and preserve pathologies in medical images. To develop such an algorithm, here, we propose DP-GLOW, a hybrid of a local differential privacy (LDP) algorithm and one of the flow-based deep generative models (GLOW). By applying a GLOW model, we disentangle the pixelwise correlation of images, which makes it difficult to protect privacy with straightforward LDP algorithms for images. Specifically, we map images onto the latent vector of the GLOW model, each element of which follows an independent normal distribution, and we apply the Laplace mechanism to the latent vector. Moreover, we applied DP-GLOW to chest X-ray images to generate LDP images while preserving pathologies.

从出生到死亡，由于老化，我们都经历了令人惊讶的无处不在的变化。如果我们可以预测数字领域的衰老，即人体的数字双胞胎，我们将能够在很早的阶段检测病变，从而提高生活质量并延长寿命。我们观察到，没有一个先前开发的成年人体数字双胞胎在具有深层生成模型的体积医学图像之间明确训练的纵向转换规则，可能导致例如心室体积的预测性能不佳。在这里，我们建立了一个新的成人人体的数字双胞胎，该数字双胞胎采用纵向获得的头部计算机断层扫描（CT）图像进行训练，从而从一个当前的体积头CT图像中预测了未来的体积头CT图像。我们首次采用了三维基于流动的深层生成模型之一，以实现这种顺序的三维数字双胞胎。我们表明，我们的数字双胞胎在相对较短的程度上优于预测心室体积的最新方法。

We consider task allocation for multi-object transport using a multi-robot system, in which each robot selects one object among multiple objects with different and unknown weights. The existing centralized methods assume the number of robots and tasks to be fixed, which is inapplicable to scenarios that differ from the learning environment. Meanwhile, the existing distributed methods limit the minimum number of robots and tasks to a constant value, making them applicable to various numbers of robots and tasks. However, they cannot transport an object whose weight exceeds the load capacity of robots observing the object. To make it applicable to various numbers of robots and objects with different and unknown weights, we propose a framework using multi-agent reinforcement learning for task allocation. First, we introduce a structured policy model consisting of 1) predesigned dynamic task priorities with global communication and 2) a neural network-based distributed policy model that determines the timing for coordination. The distributed policy builds consensus on the high-priority object under local observations and selects cooperative or independent actions. Then, the policy is optimized by multi-agent reinforcement learning through trial and error. This structured policy of local learning and global communication makes our framework applicable to various numbers of robots and objects with different and unknown weights, as demonstrated by numerical simulations.

In this paper, we present a solution to a design problem of control strategies for multi-agent cooperative transport. Although existing learning-based methods assume that the number of agents is the same as that in the training environment, the number might differ in reality considering that the robots' batteries may completely discharge, or additional robots may be introduced to reduce the time required to complete a task. Therefore, it is crucial that the learned strategy be applicable to scenarios wherein the number of agents differs from that in the training environment. In this paper, we propose a novel multi-agent reinforcement learning framework of event-triggered communication and consensus-based control for distributed cooperative transport. The proposed policy model estimates the resultant force and torque in a consensus manner using the estimates of the resultant force and torque with the neighborhood agents. Moreover, it computes the control and communication inputs to determine when to communicate with the neighboring agents under local observations and estimates of the resultant force and torque. Therefore, the proposed framework can balance the control performance and communication savings in scenarios wherein the number of agents differs from that in the training environment. We confirm the effectiveness of our approach by using a maximum of eight and six robots in the simulations and experiments, respectively.

一个由许多移动计算实体组成的自动移动机器人系统（称为机器人）吸引了研究人员的广泛关注，并阐明机器人的能力与问题的可溶性之间的关系是近几十年来的新兴问题。通常，只要没有任何机器人的数量，每个机器人都可以观察所有其他机器人。在本文中，我们提供了关于机器人观察的新观点。机器人不一定要观察所有其他机器人，而不管距离距离如何。我们称此新的计算模型瑕疵视图模型。在该模型下，在本文中，我们考虑了需要所有机器人在同一时刻收集的收集问题，并提出了两种算法来解决对抗性（$ n $，$ n-2 $）中的收集问题 - 违法模型对于$ n \ geq 5 $（每个机器人最多观察$ n-2 $机器人在对手身上选择）和基于距离的（4,2）的模型（每个机器人在最接近的机器人最接近的机器人中分别观察到）分别，其中$ n $是机器人的数量。此外，我们提出了一个不可能的结果，表明在对抗性或基于距离（3,1）的模型中没有（确定性的）收集算法。此外，我们在放松的（$ n $，$ n-2 $）中的聚会中表现出了不可能的结果。