通常,基于生物谱系的控制系统可能不依赖于各个预期行为或合作适当运行。相反,这种系统应该了解未经授权的访问尝试的恶意程序。文献中提供的一些作品建议通过步态识别方法来解决问题。这些方法旨在通过内在的可察觉功能来识别人类,尽管穿着衣服或配件。虽然该问题表示相对长时间的挑战,但是为处理问题的大多数技术存在与特征提取和低分类率相关的几个缺点,以及其他问题。然而,最近的深度学习方法是一种强大的一组工具,可以处理几乎任何图像和计算机视觉相关问题,为步态识别提供最重要的结果。因此,这项工作提供了通过步态认可的关于生物识别检测的最近作品的调查汇编,重点是深入学习方法,强调他们的益处,暴露出弱点。此外,它还呈现用于解决相关约束的数据集,方法和体系结构的分类和表征描述。
translated by 谷歌翻译
Text classification is a natural language processing (NLP) task relevant to many commercial applications, like e-commerce and customer service. Naturally, classifying such excerpts accurately often represents a challenge, due to intrinsic language aspects, like irony and nuance. To accomplish this task, one must provide a robust numerical representation for documents, a process known as embedding. Embedding represents a key NLP field nowadays, having faced a significant advance in the last decade, especially after the introduction of the word-to-vector concept and the popularization of Deep Learning models for solving NLP tasks, including Convolutional Neural Networks (CNNs), Recurrent Neural Networks (RNNs), and Transformer-based Language Models (TLMs). Despite the impressive achievements in this field, the literature coverage regarding generating embeddings for Brazilian Portuguese texts is scarce, especially when considering commercial user reviews. Therefore, this work aims to provide a comprehensive experimental study of embedding approaches targeting a binary sentiment classification of user reviews in Brazilian Portuguese. This study includes from classical (Bag-of-Words) to state-of-the-art (Transformer-based) NLP models. The methods are evaluated with five open-source databases with pre-defined data partitions made available in an open digital repository to encourage reproducibility. The Fine-tuned TLMs achieved the best results for all cases, being followed by the Feature-based TLM, LSTM, and CNN, with alternate ranks, depending on the database under analysis.
translated by 谷歌翻译
本文提出了一种新的方法,该方法结合了卷积层(CLS)和大规模的度量度量,用于在小数据集上进行培训模型以进行纹理分类。这种方法的核心是损失函数,该函数计算了感兴趣的实例和支持向量之间的距离。目的是在迭代中更新CLS的权重,以学习一类之间具有较大利润的表示形式。每次迭代都会产生一个基于这种表示形式的支持向量表示的大细边缘判别模型。拟议方法的优势W.R.T.卷积神经网络(CNN)为两倍。首先,由于参数数量减少,与等效的CNN相比,它允许用少量数据进行表示。其次,自返回传播仅考虑支持向量以来,它的培训成本较低。关于纹理和组织病理学图像数据集的实验结果表明,与等效的CNN相比,所提出的方法以较低的计算成本和更快的收敛性达到了竞争精度。
translated by 谷歌翻译
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.
translated by 谷歌翻译
State-of-the-art brain tumor segmentation is based on deep learning models applied to multi-modal MRIs. Currently, these models are trained on images after a preprocessing stage that involves registration, interpolation, brain extraction (BE, also known as skull-stripping) and manual correction by an expert. However, for clinical practice, this last step is tedious and time-consuming and, therefore, not always feasible, resulting in skull-stripping faults that can negatively impact the tumor segmentation quality. Still, the extent of this impact has never been measured for any of the many different BE methods available. In this work, we propose an automatic brain tumor segmentation pipeline and evaluate its performance with multiple BE methods. Our experiments show that the choice of a BE method can compromise up to 15.7% of the tumor segmentation performance. Moreover, we propose training and testing tumor segmentation models on non-skull-stripped images, effectively discarding the BE step from the pipeline. Our results show that this approach leads to a competitive performance at a fraction of the time. We conclude that, in contrast to the current paradigm, training tumor segmentation models on non-skull-stripped images can be the best option when high performance in clinical practice is desired.
translated by 谷歌翻译
Chronic pain is a multi-dimensional experience, and pain intensity plays an important part, impacting the patients emotional balance, psychology, and behaviour. Standard self-reporting tools, such as the Visual Analogue Scale for pain, fail to capture this burden. Moreover, this type of tools is susceptible to a degree of subjectivity, dependent on the patients clear understanding of how to use it, social biases, and their ability to translate a complex experience to a scale. To overcome these and other self-reporting challenges, pain intensity estimation has been previously studied based on facial expressions, electroencephalograms, brain imaging, and autonomic features. However, to the best of our knowledge, it has never been attempted to base this estimation on the patient narratives of the personal experience of chronic pain, which is what we propose in this work. Indeed, in the clinical assessment and management of chronic pain, verbal communication is essential to convey information to physicians that would otherwise not be easily accessible through standard reporting tools, since language, sociocultural, and psychosocial variables are intertwined. We show that language features from patient narratives indeed convey information relevant for pain intensity estimation, and that our computational models can take advantage of that. Specifically, our results show that patients with mild pain focus more on the use of verbs, whilst moderate and severe pain patients focus on adverbs, and nouns and adjectives, respectively, and that these differences allow for the distinction between these three pain classes.
translated by 谷歌翻译
在多语言甚至单语言中鉴定的模型的零拍跨语言能力刺激了许多假设,以解释这一有趣的经验结果。但是,由于预处理的成本,大多数研究都使用公共模型的公共模型,其预处理方法(例如代币化,语料库规模和计算预算的选择)可能会大不相同。当研究人员对自己的模型预识时,他们通常会在预算有限的情况下这样做,并且与SOTA模型相比,最终的模型的表现可能明显不足。这些实验差异导致有关这些模型跨语性能力的性质的各种不一致的结论。为了帮助对该主题进行进一步研究,我们发布了10个单语字节级模型,并在相同的配置下进行了严格审慎的概述,并具有大型计算预算(相当于V100的420天)和Corpora,比原始BERT大4倍。由于它们不含令牌,因此消除了看不见的令牌嵌入的问题,从而使研究人员可以在具有不同脚本的语言中尝试更广泛的跨语言实验。此外,我们释放了在不自然语言文本上预测的两个模型,这些模型可用于理智检查实验。关于质量检查和NLI任务的实验表明,我们的单语模型实现了多语言的竞争性能,因此可以加强我们对语言模型中跨语性可传递性的理解。
translated by 谷歌翻译
最近证明利用稀疏网络连接深神经网络中的连续层,可为大型最新模型提供好处。但是,网络连接性在浅网络的学习曲线中也起着重要作用,例如经典限制的玻尔兹曼机器(RBM)。一个基本问题是有效地找到了改善学习曲线的连接模式。最近的原则方法明确将网络连接作为参数,这些参数必须在模型中进行优化,但通常依靠连续功能来表示连接和明确的惩罚。这项工作提出了一种基于网络梯度的想法来找到RBM的最佳连接模式的方法:计算每个可能连接的梯度,给定特定的连接模式,并使用梯度驱动连续连接强度参数又使用确定连接模式。因此,学习RBM参数和学习网络连接是真正共同执行的,尽管学习率不同,并且没有改变目标函数。该方法应用于MNIST数据集,以显示针对样本生成和输入分类的基准任务找到更好的RBM模型。
translated by 谷歌翻译
我们介绍了IST和Unmabel对WMT 2022关于质量估计(QE)的共享任务的共同贡献。我们的团队参与了所有三个子任务:(i)句子和单词级质量预测;(ii)可解释的量化宽松;(iii)关键错误检测。对于所有任务,我们在彗星框架之上构建,将其与OpenKIWI的预测估计架构连接,并为其配备单词级序列标记器和解释提取器。我们的结果表明,在预处理过程中合并参考可以改善下游任务上多种语言对的性能,并且通过句子和单词级别的目标共同培训可以进一步提高。此外,将注意力和梯度信息结合在一起被证明是提取句子级量化量化宽松模型的良好解释的首要策略。总体而言,我们的意见书在几乎所有语言对的所有三个任务中都取得了最佳的结果。
translated by 谷歌翻译
对心脏周围环境的脂肪库的定量是评估与多种疾病相关的健康风险因素的准确程序。但是,由于人为的工作量,这种类型的评估并未在临床实践中广泛使用。这项工作提出了一种用于自动分割心脏脂肪垫的新技术。该技术基于将分类算法应用于心脏CT图像的分割。此外,我们广泛评估了几种算法在此任务上的性能,并讨论了提供了更好的预测模型。实验结果表明,心外膜和纵隔脂肪分类的平均准确性为98.4%,平均正面速率为96.2%。平均而言,关于分割的患者和地面真相的骰子相似性指数等于96.8%。因此,迄今为止,我们的技术已经获得了心脏脂肪自动分割的最准确结果。
translated by 谷歌翻译