The ability to effectively reuse prior knowledge is a key requirement when building general and flexible Reinforcement Learning (RL) agents. Skill reuse is one of the most common approaches, but current methods have considerable limitations.For example, fine-tuning an existing policy frequently fails, as the policy can degrade rapidly early in training. In a similar vein, distillation of expert behavior can lead to poor results when given sub-optimal experts. We compare several common approaches for skill transfer on multiple domains including changes in task and system dynamics. We identify how existing methods can fail and introduce an alternative approach to mitigate these problems. Our approach learns to sequence existing temporally-extended skills for exploration but learns the final policy directly from the raw experience. This conceptual split enables rapid adaptation and thus efficient data collection but without constraining the final solution.It significantly outperforms many classical methods across a suite of evaluation tasks and we use a broad set of ablations to highlight the importance of differentc omponents of our method.

对于在现实世界中运营的机器人来说，期望学习可以有效地转移和适应许多任务和场景的可重复使用的行为。我们提出了一种使用分层混合潜变量模型来从数据中学习抽象运动技能的方法。与现有工作相比，我们的方法利用了离散和连续潜在变量的三级层次结构，以捕获一组高级行为，同时允许如何执行它们的差异。我们在操纵域中展示该方法可以有效地将离线数据脱落到不同的可执行行为，同时保留连续潜变量模型的灵活性。由此产生的技能可以在新的任务，看不见的对象和州内转移和微调到基于视觉的策略，与现有的技能和仿制的方法相比，产生更好的样本效率和渐近性能。我们进一步分析了技能最有益的方式以及何时：他们鼓励定向探索来涵盖与任务相关的国家空间的大区域，使其在挑战稀疏奖励环境中最有效。

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.

It does not matter whether it is a job interview with Tech Giants, Wall Street firms, or a small startup; all candidates want to demonstrate their best selves or even present themselves better than they really are. Meanwhile, recruiters want to know the candidates' authentic selves and detect soft skills that prove an expert candidate would be a great fit in any company. Recruiters worldwide usually struggle to find employees with the highest level of these skills. Digital footprints can assist recruiters in this process by providing candidates' unique set of online activities, while social media delivers one of the largest digital footprints to track people. In this study, for the first time, we show that a wide range of behavioral competencies consisting of 16 in-demand soft skills can be automatically predicted from Instagram profiles based on the following lists and other quantitative features using machine learning algorithms. We also provide predictions on Big Five personality traits. Models were built based on a sample of 400 Iranian volunteer users who answered an online questionnaire and provided their Instagram usernames which allowed us to crawl the public profiles. We applied several machine learning algorithms to the uniformed data. Deep learning models mostly outperformed by demonstrating 70% and 69% average Accuracy in two-level and three-level classifications respectively. Creating a large pool of people with the highest level of soft skills, and making more accurate evaluations of job candidates is possible with the application of AI on social media user-generated data.

Cardiac resynchronization therapy (CRT) is a treatment that is used to compensate for irregularities in the heartbeat. Studies have shown that this treatment is more effective in heart patients with left bundle branch block (LBBB) arrhythmia. Therefore, identifying this arrhythmia is an important initial step in determining whether or not to use CRT. On the other hand, traditional methods for detecting LBBB on electrocardiograms (ECG) are often associated with errors. Thus, there is a need for an accurate method to diagnose this arrhythmia from ECG data. Machine learning, as a new field of study, has helped to increase human systems' performance. Deep learning, as a newer subfield of machine learning, has more power to analyze data and increase systems accuracy. This study presents a deep learning model for the detection of LBBB arrhythmia from 12-lead ECG data. This model consists of 1D dilated convolutional layers. Attention mechanism has also been used to identify important input data features and classify inputs more accurately. The proposed model is trained and validated on a database containing 10344 12-lead ECG samples using the 10-fold cross-validation method. The final results obtained by the model on the 12-lead ECG data are as follows. Accuracy: 98.80+-0.08%, specificity: 99.33+-0.11 %, F1 score: 73.97+-1.8%, and area under the receiver operating characteristics curve (AUC): 0.875+-0.0192. These results indicate that the proposed model in this study can effectively diagnose LBBB with good efficiency and, if used in medical centers, will greatly help diagnose this arrhythmia and early treatment.

Federated Learning (FL) is a scheme for collaboratively training Deep Neural Networks (DNNs) with multiple data sources from different clients. Instead of sharing the data, each client trains the model locally, resulting in improved privacy. However, recently so-called targeted poisoning attacks have been proposed that allow individual clients to inject a backdoor into the trained model. Existing defenses against these backdoor attacks either rely on techniques like Differential Privacy to mitigate the backdoor, or analyze the weights of the individual models and apply outlier detection methods that restricts these defenses to certain data distributions. However, adding noise to the models' parameters or excluding benign outliers might also reduce the accuracy of the collaboratively trained model. Additionally, allowing the server to inspect the clients' models creates a privacy risk due to existing knowledge extraction methods. We propose CrowdGuard, a model filtering defense, that mitigates backdoor attacks by leveraging the clients' data to analyze the individual models before the aggregation. To prevent data leaks, the server sends the individual models to secure enclaves, running in client-located Trusted Execution Environments. To effectively distinguish benign and poisoned models, even if the data of different clients are not independently and identically distributed (non-IID), we introduce a novel metric called HLBIM to analyze the outputs of the DNN's hidden layers. We show that the applied significance-based detection algorithm combined can effectively detect poisoned models, even in non-IID scenarios. We show in our extensive evaluation that CrowdGuard can effectively mitigate targeted poisoning attacks and achieve in various scenarios a True-Positive-Rate of 100% and a True-Negative-Rate of 100%.

人们的行为和反应是由他们的情绪驱动的。在线社交媒体正在成为以书面形式表达情感的绝佳工具。注意上下文和整个句子，帮助我们从文本中检测到情感。但是，这种观点抑制了我们注意文本中的一些情感单词或短语，尤其是当单词隐含地而不是明确地表达情感时。另一方面，仅关注单词并忽略上下文会导致对句子含义和感觉的扭曲理解。在本文中，我们提出了一个框架，该框架分析句子和单词级别的文本。我们将其命名为CEFER（情感识别的上下文和情感嵌入式框架）。我们的四个方法是通过同时考虑整个句子和每个单词以及隐式和明确的情绪来提取数据。从这些数据中获得的知识不仅减轻了前面方法中缺陷的影响，而且还可以增强特征向量。我们使用BERT家族评估几个功能空间，并根据其设计CEFER。 CEFER将每个单词的情感向量（包括明确和隐性情绪）与基于上下文的每个单词的特征向量相结合。 CEFER的表现比Bert家族更好。实验结果表明，识别隐性情绪比检测明确的情绪更具挑战性。 CEFER，提高了隐性情绪识别的准确性。根据结果​​，CEFER在识别明确的情绪和隐性中的3％方面的表现要比BERT家族好5％。

通过查找图像可能不满意的图像来捕获对象检测器的错误行为，这一兴趣很长。在实际应用（例如自动驾驶）中，对于表征除了简单的检测性能要求之外的潜在失败也至关重要。例如，与远处未遗漏的汽车检测相比，错过对靠近自我车辆的行人的侦查通常需要更仔细的检查。在测试时间预测这种潜在失败的问题在文献和基于检测不确定性的传统方法中被忽略了，因为它们对这种错误的细粒度表征不可知。在这项工作中，我们建议将查找“硬”图像作为基于查询的硬图像检索任务的问题进行重新制定，其中查询是“硬度”的特定定义，并提供了一种简单而直观的方法，可以解决此任务大型查询家庭。我们的方法完全是事后的，不需要地面真相注释，独立于检测器的选择，并且依赖于有效的蒙特卡洛估计，该估计使用简单的随机模型代替地面真相。我们通过实验表明，它可以成功地应用于各种查询中，它可以可靠地识别给定检测器的硬图像，而无需任何标记的数据。我们使用广泛使用的视网膜，更快的RCNN，Mask-RCNN和CASCADE MASK-RCNN对象检测器提供有关排名和分类任务的结果。

实现安全和强大的自主权是通往更广泛采用自动驾驶汽车技术的道路的关键瓶颈。这激发了超越外在指标，例如脱离接触之间的里程，并呼吁通过设计体现安全的方法。在本文中，我们解决了这一挑战的某些方面，重点是运动计划和预测问题。我们通过描述在自动驾驶堆栈中解决选定的子问题所采取的新方法的描述，在介绍五个之内采用的设计理念的过程中。这包括安全的设计计划，可解释以及可验证的预测以及对感知错误的建模，以在现实自主系统的测试管道中实现有效的SIM到现实和真实的SIM转移。

我们研究在线交互式强盗设置中的非模块化功能。我们是受到某些元素之间自然互补性的应用程序的动机：这仅使用只能代表元素之间竞争力的下函数来表达这一点。我们通过两种方式扩展了纯粹的下二次方法。首先，我们假设该物镜可以分解为单调下模量和超模块函数的总和，称为BP物镜。在这里，互补性自然是由超模型成分建模的。我们开发了UCB风格的算法，在每一轮比赛中，在采取行动以平衡对未知目标（探索）和选择似乎有希望的行动（剥削）的行动之间揭示的嘈杂收益。根据全知识的贪婪基线来定义遗憾和超模块化曲率，我们表明该算法最多可以在$ o（\ sqrt {t}）$ hore $ t $ t $ t $ the $ t $ t $ the $ t $ t $ the $ the。其次，对于那些不承认BP结构的功能，我们提供了类似的遗憾保证，从其表现比率角度来看。这适用于几乎但不完全是子模型的功能。我们在数值上研究了Movielens数据集上电影推荐的任务，并选择用于分类的培训子集。通过这些示例，我们证明了该算法的性能以及将这些问题视为单次生管的缺点。