\ textit {objection：}基于gadolinium的对比剂（GBCA）已被广泛用于更好地可视化脑磁共振成像中的疾病（MRI）。然而，大脑和身体内部的gadolin量引起了人们对使用GBCA的安全问题。因此，在提供类似的对比度信息的同时，可以减少甚至消除GBCA暴露的新方法的发展将在临床上具有重大用途。 \ textit {方法：}在这项工作中，我们提出了一种基于深度学习的方法，用于对脑肿瘤患者的对比增强T1合成。 3D高分辨率完全卷积网络（FCN）通过处理和聚合并行的多尺度信息保持高分辨率信息，旨在将前对比度MRI序列映射到对比度增强的MRI序列。具体而言，将三个前对比的MRI序列T1，T2和表观扩散系数图（ADC）用作输入，而对比后T1序列则被用作目标输出。为了减轻正常组织与肿瘤区域之间的数据不平衡问题，我们引入了局部损失，以改善肿瘤区域的贡献，从而可以更好地增强对肿瘤的增强结果。 \ textIt {结果：}进行了广泛的定量和视觉评估，我们提出的模型在大脑中达到28.24db的PSNR，在肿瘤区域达到21.2db。 \ textit {结论和意义：}我们的结果表明，用深度学习产生的合成对比图像代替GBCA的潜力。代码可在\ url {https://github.com/chenchao666/contrast-enhanced-mri-synthesis中获得

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.

The number of international benchmarking competitions is steadily increasing in various fields of machine learning (ML) research and practice. So far, however, little is known about the common practice as well as bottlenecks faced by the community in tackling the research questions posed. To shed light on the status quo of algorithm development in the specific field of biomedical imaging analysis, we designed an international survey that was issued to all participants of challenges conducted in conjunction with the IEEE ISBI 2021 and MICCAI 2021 conferences (80 competitions in total). The survey covered participants' expertise and working environments, their chosen strategies, as well as algorithm characteristics. A median of 72% challenge participants took part in the survey. According to our results, knowledge exchange was the primary incentive (70%) for participation, while the reception of prize money played only a minor role (16%). While a median of 80 working hours was spent on method development, a large portion of participants stated that they did not have enough time for method development (32%). 25% perceived the infrastructure to be a bottleneck. Overall, 94% of all solutions were deep learning-based. Of these, 84% were based on standard architectures. 43% of the respondents reported that the data samples (e.g., images) were too large to be processed at once. This was most commonly addressed by patch-based training (69%), downsampling (37%), and solving 3D analysis tasks as a series of 2D tasks. K-fold cross-validation on the training set was performed by only 37% of the participants and only 50% of the participants performed ensembling based on multiple identical models (61%) or heterogeneous models (39%). 48% of the respondents applied postprocessing steps.

许多现实世界中的问题都包含多个目标和代理，其中目标之间存在权衡。解决此类问题的关键是利用代理之间存在的稀疏依赖性结构。例如，在风电场控制中，在最大化功率和最大程度地减少对系统组件的压力之间存在权衡。涡轮机之间的依赖性是由于唤醒效应而产生的。我们将这种稀疏依赖性模拟为多目标配位图（MO-COG）。在多目标强化学习实用程序功能通常用于对用户偏好而不是目标建模，这可能是未知的。在这种情况下，必须计算一组最佳策略。哪些策略是最佳的，取决于哪些最佳标准适用。如果用户的效用函数是从策略的多个执行中得出的，则必须优化标识的预期收益（SER）。如果用户的效用是从策略的单个执行中得出的，则必须优化预期的标量回报（ESR）标准。例如，风电场受到必须始终遵守的限制和法规，因此必须优化ESR标准。对于Mo-COG，最新的算法只能计算一组SER标准的最佳策略，而ESR标准进行了研究。要计算在ESR标准下（也称为ESR集合）下的一组最佳策略，必须维护回报上的分布。因此，为了计算MO-COGS的ESR标准下的一组最佳策略，我们提出了一种新型的分布多目标变量消除（DMOVE）算法。我们在逼真的风电场模拟中评估了DMOVE。鉴于实际风电场设置中的回报是连续的，我们使用称为Real-NVP的模型来学习连续的返回分布来计算ESR集合。

历史流程表现出显着的多样性。尽管如此，学者们长期以来一直试图识别模式，并将历史行动者分类和对一些成功的影响。随机过程框架提供了一种结构化方法，用于分析大型历史数据集，允许检测有时令人惊讶的模式，鉴定内源性和外源对过程的相关因果作用者，以及不同历史案例的比较。随机过程的数据，分析工具和组织理论框架的组合使历史和考古中的传统叙事方法补充了传统的叙事方法。

在许多实际情况下，用户的实用程序来自策略的单个执行。在这种情况下，要应用多目标增强学习，必须优化收益的预期效用。存在各种方案，其中用户对目标（也称为实用程序功能）的偏好是未知或难以指定的。在这种情况下，必须学习一组最佳政策。但是，多目标增强学习社区必须最大程度地忽略了必须最大程度地提高预期效用的设置，结果，一组最佳解决方案尚未定义。在本文中，我们通过提出一阶随机优势作为建立解决方案集以最大化预期效用的标准来应对这一挑战。我们还提出了一种新的优势标准，称为预期标量回报（ESR）优势，该标准率扩展了一阶随机优势，以允许在实践中学习一组最佳策略。然后，我们定义一个称为ESR集的新解决方案概念，该概念是ESR主导的一组策略。最后，我们定义了一种新的多目标分布表格增强学习（MOT-DRL）算法，以在多目标多臂强盗设置中学习设置的ESR。

目前，由精确的径向速度（RV）观察结果受到恒星活性引入的虚假RV信号的限制。我们表明，诸如线性回归和神经网络之类的机器学习技术可以有效地从RV观测中删除活动信号（由于星形/张图引起的）。先前的工作着重于使用高斯工艺回归等建模技术仔细地过滤活性信号（例如Haywood等人，2014年）。取而代之的是，我们仅使用对光谱线平均形状的更改进行系统地删除活动信号，也没有有关收集观测值的信息。我们对模拟数据（使用SOAP 2.0软件生成； Dumusque等人，2014年生成）和从Harps-N太阳能望远镜（Dumusque等，2015; Phillips等人2015; 2016; Collier训练）培训了机器学习模型。 Cameron等人2019）。我们发现，这些技术可以从模拟数据（将RV散射从82 cm/s提高到3 cm/s）以及从HARPS-N太阳能望远镜中几乎每天进行的600多种真实观察结果来预测和消除恒星活动（将RV散射从82 cm/s提高到3 cm/s）。 （将RV散射从1.753 m/s提高到1.039 m/s，提高了约1.7倍）。将来，这些或类似的技术可能会从太阳系以外的恒星观察中去除活动信号，并最终有助于检测到阳光状恒星周围可居住的区域质量系外行星。

This paper presents a machine learning approach to multidimensional item response theory (MIRT), a class of latent factor models that can be used to model and predict student performance from observed assessment data. Inspired by collaborative filtering, we define a general class of models that includes many MIRT models. We discuss the use of penalized joint maximum likelihood (JML) to estimate individual models and cross-validation to select the best performing model. This model evaluation process can be optimized using batching techniques, such that even sparse large-scale data can be analyzed efficiently. We illustrate our approach with simulated and real data, including an example from a massive open online course (MOOC). The high-dimensional model fit to this large and sparse dataset does not lend itself well to traditional methods of factor interpretation. By analogy to recommender-system applications, we propose an alternative "validation" of the factor model, using auxiliary information about the popularity of items consulted during an open-book exam in the course.

Real-world robotic grasping can be done robustly if a complete 3D Point Cloud Data (PCD) of an object is available. However, in practice, PCDs are often incomplete when objects are viewed from few and sparse viewpoints before the grasping action, leading to the generation of wrong or inaccurate grasp poses. We propose a novel grasping strategy, named 3DSGrasp, that predicts the missing geometry from the partial PCD to produce reliable grasp poses. Our proposed PCD completion network is a Transformer-based encoder-decoder network with an Offset-Attention layer. Our network is inherently invariant to the object pose and point's permutation, which generates PCDs that are geometrically consistent and completed properly. Experiments on a wide range of partial PCD show that 3DSGrasp outperforms the best state-of-the-art method on PCD completion tasks and largely improves the grasping success rate in real-world scenarios. The code and dataset will be made available upon acceptance.

Using Structural Health Monitoring (SHM) systems with extensive sensing arrangements on every civil structure can be costly and impractical. Various concepts have been introduced to alleviate such difficulties, such as Population-based SHM (PBSHM). Nevertheless, the studies presented in the literature do not adequately address the challenge of accessing the information on different structural states (conditions) of dissimilar civil structures. The study herein introduces a novel framework named Structural State Translation (SST), which aims to estimate the response data of different civil structures based on the information obtained from a dissimilar structure. SST can be defined as Translating a state of one civil structure to another state after discovering and learning the domain-invariant representation in the source domains of a dissimilar civil structure. SST employs a Domain-Generalized Cycle-Generative (DGCG) model to learn the domain-invariant representation in the acceleration datasets obtained from a numeric bridge structure that is in two different structural conditions. In other words, the model is tested on three dissimilar numeric bridge models to translate their structural conditions. The evaluation results of SST via Mean Magnitude-Squared Coherence (MMSC) and modal identifiers showed that the translated bridge states (synthetic states) are significantly similar to the real ones. As such, the minimum and maximum average MMSC values of real and translated bridge states are 91.2% and 97.1%, the minimum and the maximum difference in natural frequencies are 5.71% and 0%, and the minimum and maximum Modal Assurance Criterion (MAC) values are 0.998 and 0.870. This study is critical for data scarcity and PBSHM, as it demonstrates that it is possible to obtain data from structures while the structure is actually in a different condition or state.