近年来，在全球范围内解决了强大的智能运输系统（ITS）的开发，以通过减少频繁的交通问题来提高交通效率。作为其应用，车辆的重新识别对计算机视觉和机器人技术的领域产生了充足的兴趣。开发了基于卷积的神经网络（CNN）方法来执行车辆重新识别，以应对诸如遮挡，照明变化，规模等的关键挑战。计算机视觉中变形金刚的进步已经为进一步探索重新识别流程提供了机会提高性能。在本文中，开发了一个框架来执行跨CCTV摄像机的车辆的重新识别。为了进行重新识别，提出的框架将使用CNN和变压器模型学习的车辆表示。该框架在一个数据集上进行了测试，该数据集包含在20个CCTV摄像机上观察到的81个独特的车辆身份。从实验中，融合的车辆重新识别框架的地图为61.73％，与独立的CNN或变压器模型相比，该框架的地图明显更好。

森林在减少温室气体排放和缓解气候变化方面起着至关重要的作用，除了维持世界的生物多样性。现有的基于卫星的森林监测系统利用受监督的学习方法仅限于特定区域，并依靠手动注释的数据来识别森林。这项工作将森林识别视为几乎没有语义分割任务，以实现在不同地理区域的概括。提出的几片分段方法包含了原型网络中的纹理注意模块，以突出森林的质地特征。的确，森林表现出与其他类别不同的​​特征性质地，例如道路，水等。在这项工作中，拟议的方法经过培训，可以识别南亚的热带森林，并在帮助下改编以确定中欧的温带森林。在温带森林的一些（1张图像）手动注释的支撑图像中。使用所提出的方法获得了森林类别（1向1射击）的0.62的IOU，该方法比现有的几弹性语义分割方法高得多（锅盘为0.46）。该结果表明，所提出的方法可以概括整个地理区域以进行森林识别，从而创造了开发全球森林覆盖识别工具的机会。

大多数机器学习模型在假设培训，测试和部署数据是独立的和相同分布的假设下运行（i.i.d.）。这种假设通常在自然设置中通常保持真实。通常，部署数据受各种类型的分布换档。模型性能的大小与数据集分发的这种转变成比例。因此，有必要评估模型的不确定性和稳健性，以分配转变，以便在真实数据上实现其预期绩效的现实估计。提供评估不确定性和模型的鲁棒性的现有方法缺乏，并且通常无法涂漆完整的图片。此外，到目前为止大多数分析主要专注于分类任务。在本文中，我们使用Shifts天气预报数据集提出了更多的始终回归任务的有洞察力度量。我们还提供了使用这些指标的基线方法的评估。

Mixup is a popular data augmentation technique for training deep neural networks where additional samples are generated by linearly interpolating pairs of inputs and their labels. This technique is known to improve the generalization performance in many learning paradigms and applications. In this work, we first analyze Mixup and show that it implicitly regularizes infinitely many directional derivatives of all orders. We then propose a new method to improve Mixup based on the novel insight. To demonstrate the effectiveness of the proposed method, we conduct experiments across various domains such as images, tabular data, speech, and graphs. Our results show that the proposed method improves Mixup across various datasets using a variety of architectures, for instance, exhibiting an improvement over Mixup by 0.8% in ImageNet top-1 accuracy.

In multi-agent systems with large number of agents, typically the contribution of each agent to the value of other agents is minimal (e.g., aggregation systems such as Uber, Deliveroo). In this paper, we consider such multi-agent systems where each agent is self-interested and takes a sequence of decisions and represent them as a Stochastic Non-atomic Congestion Game (SNCG). We derive key properties for equilibrium solutions in SNCG model with non-atomic and also nearly non-atomic agents. With those key equilibrium properties, we provide a novel Multi-Agent Reinforcement Learning (MARL) mechanism that minimizes variance across values of agents in the same state. To demonstrate the utility of this new mechanism, we provide detailed results on a real-world taxi dataset and also a generic simulator for aggregation systems. We show that our approach reduces the variance in revenues earned by taxi drivers, while still providing higher joint revenues than leading approaches.

This thesis considers sequential decision problems, where the loss/reward incurred by selecting an action may not be inferred from observed feedback. A major part of this thesis focuses on the unsupervised sequential selection problem, where one can not infer the loss incurred for selecting an action from observed feedback. We also introduce a new setup named Censored Semi Bandits, where the loss incurred for selecting an action can be observed under certain conditions. Finally, we study the channel selection problem in the communication networks, where the reward for an action is only observed when no other player selects that action to play in the round. These problems find applications in many fields like healthcare, crowd-sourcing, security, adaptive resource allocation, among many others. This thesis aims to address the above-described sequential decision problems by exploiting specific structures these problems exhibit. We develop provably optimal algorithms for each of these setups with weak feedback and validate their empirical performance on different problem instances derived from synthetic and real datasets.

This thesis considers sequential decision problems, where the loss/reward incurred by selecting an action may not be inferred from observed feedback. A major part of this thesis focuses on the unsupervised sequential selection problem, where one can not infer the loss incurred for selecting an action from observed feedback. We also introduce a new setup named Censored Semi Bandits, where the loss incurred for selecting an action can be observed under certain conditions. Finally, we study the channel selection problem in the communication networks, where the reward for an action is only observed when no other player selects that action to play in the round. These problems find applications in many fields like healthcare, crowd-sourcing, security, adaptive resource allocation, among many others. This thesis aims to address the above-described sequential decision problems by exploiting specific structures these problems exhibit. We develop provably optimal algorithms for each of these setups with weak feedback and validate their empirical performance on different problem instances derived from synthetic and real datasets.

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.

Masked Language Modeling (MLM) has proven to be an essential component of Vision-Language (VL) pretraining. To implement MLM, the researcher must make two design choices: the masking strategy, which determines which tokens to mask, and the masking rate, which determines how many tokens to mask. Previous work has focused primarily on the masking strategy while setting the masking rate at a default of 15\%. In this paper, we show that increasing this masking rate improves downstream performance while simultaneously reducing performance gap among different masking strategies, rendering the uniform masking strategy competitive to other more complex ones. Surprisingly, we also discover that increasing the masking rate leads to gains in Image-Text Matching (ITM) tasks, suggesting that the role of MLM goes beyond language modeling in VL pretraining.

Artificial Intelligence (AI) systems have been increasingly used to make decision-making processes faster, more accurate, and more efficient. However, such systems are also at constant risk of being attacked. While the majority of attacks targeting AI-based applications aim to manipulate classifiers or training data and alter the output of an AI model, recently proposed Sponge Attacks against AI models aim to impede the classifier's execution by consuming substantial resources. In this work, we propose \textit{Dual Denial of Decision (DDoD) attacks against collaborative Human-AI teams}. We discuss how such attacks aim to deplete \textit{both computational and human} resources, and significantly impair decision-making capabilities. We describe DDoD on human and computational resources and present potential risk scenarios in a series of exemplary domains.