这项研究受到人类行为的启发,提议使用探测策略,并将其整合到遍布性分析框架中,以解决未知的粗糙地形上的安全导航。我们的框架将可折叠信息整合到我们现有的遍历性分析中,因为仅视力和几何信息可能会被不可预测的非刚性地形(例如柔软的土壤,灌木丛或水坑)误导。通过新的遍历性分析框架,我们的机器人对不可预测的地形进行了更全面的评估,这对于其在室外环境中的安全至关重要。该管道首先使用RGB-D摄像头确定地形的几何和语义性能,并在可疑地形上探测位置。使用力传感器对这些区域进行探测,以确定机器人在其上面时崩溃的风险。该风险被称为可折叠度度量,该指标估计了不可预测的区域的地面可折叠性。此后,将可折叠性度量以及几何和语义空间数据结合在一起,并分析以产生全局和局部穿术网格图。这些遍历性网格地图告诉机器人是否可以安全地跨越地图的不同区域。然后使用网格图来生成机器人的最佳路径,以安全地导航其目标。在模拟和现实世界实验中,我们的方法已在四足动物的机器人上成功验证。
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Large language models (LLMs) have demonstrated impressive capabilities in natural language understanding and generation, but the quality bar for medical and clinical applications is high. Today, attempts to assess models' clinical knowledge typically rely on automated evaluations on limited benchmarks. There is no standard to evaluate model predictions and reasoning across a breadth of tasks. To address this, we present MultiMedQA, a benchmark combining six existing open question answering datasets spanning professional medical exams, research, and consumer queries; and HealthSearchQA, a new free-response dataset of medical questions searched online. We propose a framework for human evaluation of model answers along multiple axes including factuality, precision, possible harm, and bias. In addition, we evaluate PaLM (a 540-billion parameter LLM) and its instruction-tuned variant, Flan-PaLM, on MultiMedQA. Using a combination of prompting strategies, Flan-PaLM achieves state-of-the-art accuracy on every MultiMedQA multiple-choice dataset (MedQA, MedMCQA, PubMedQA, MMLU clinical topics), including 67.6% accuracy on MedQA (US Medical License Exam questions), surpassing prior state-of-the-art by over 17%. However, human evaluation reveals key gaps in Flan-PaLM responses. To resolve this we introduce instruction prompt tuning, a parameter-efficient approach for aligning LLMs to new domains using a few exemplars. The resulting model, Med-PaLM, performs encouragingly, but remains inferior to clinicians. We show that comprehension, recall of knowledge, and medical reasoning improve with model scale and instruction prompt tuning, suggesting the potential utility of LLMs in medicine. Our human evaluations reveal important limitations of today's models, reinforcing the importance of both evaluation frameworks and method development in creating safe, helpful LLM models for clinical applications.
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The task of Compositional Zero-Shot Learning (CZSL) is to recognize images of novel state-object compositions that are absent during the training stage. Previous methods of learning compositional embedding have shown effectiveness in closed-world CZSL. However, in Open-World CZSL (OW-CZSL), their performance tends to degrade significantly due to the large cardinality of possible compositions. Some recent works separately predict simple primitives (i.e., states and objects) to reduce cardinality. However, they consider simple primitives as independent probability distributions, ignoring the heavy dependence between states, objects, and compositions. In this paper, we model the dependence of compositions via feasibility and contextuality. Feasibility-dependence refers to the unequal feasibility relations between simple primitives, e.g., \textit{hairy} is more feasible with \textit{cat} than with \textit{building} in the real world. Contextuality-dependence represents the contextual variance in images, e.g., \textit{cat} shows diverse appearances under the state of \textit{dry} and \textit{wet}. We design Semantic Attention (SA) and generative Knowledge Disentanglement (KD) to learn the dependence of feasibility and contextuality, respectively. SA captures semantics in compositions to alleviate impossible predictions, driven by the visual similarity between simple primitives. KD disentangles images into unbiased feature representations, easing contextual bias in predictions. Moreover, we complement the current compositional probability model with feasibility and contextuality in a compatible format. Finally, we conduct comprehensive experiments to analyze and validate the superior or competitive performance of our model, Semantic Attention and knowledge Disentanglement guided Simple Primitives (SAD-SP), on three widely-used benchmark OW-CZSL datasets.
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事件提取是医学文本处理的重要工作。根据医学文本注释的复杂特征,我们使用端到端事件提取模型来增强事件的输出格式信息。通过预训练和微调,我们可以提取医学文本四个维度的属性:解剖位置,主题单词,描述单词和发生状态。在测试集中,准确率为0.4511,召回率为0.3928,F1值为0.42。该模型的方法很简单,并且在第七届中国健康信息处理会议(CHIP2021)的中国电子医疗记录中赢得了挖掘临床发现事件(任务2)的任务中的第二名。
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图形神经网络(GNN)在解决图形结构数据(即网络)方面的各种分析任务方面已广受欢迎。典型的gnns及其变体遵循一种消息的方式,该方式通过网络拓扑沿网络拓扑的特征传播过程获得网络表示,然而,它们忽略了许多现实世界网络中存在的丰富文本语义(例如,局部单词序列)。现有的文本丰富网络方法通过主要利用内部信息(例如主题或短语/单词)来整合文本语义,这些信息通常无法全面地挖掘文本语义,从而限制了网络结构和文本语义之间的相互指导。为了解决这些问题,我们提出了一个具有外部知识(TEKO)的新型文本富裕的图形神经网络,以充分利用文本丰富的网络中的结构和文本信息。具体而言,我们首先提出一个灵活的异质语义网络,该网络结合了文档和实体之间的高质量实体和互动。然后,我们介绍两种类型的外部知识,即结构化的三胞胎和非结构化实体描述,以更深入地了解文本语义。我们进一步为构建的异质语义网络设计了互惠卷积机制,使网络结构和文本语义能够相互协作并学习高级网络表示。在四个公共文本丰富的网络以及一个大规模的电子商务搜索数据集上进行了广泛的实验结果,这说明了Teko优于最先进的基线。
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由于单个RGB图像的不利低对比度和弱可见性问题,低光图像增强(LLE)仍然具有挑战性。在本文中,我们回应了有趣的学习相关问题 - 如果利用可访问的既可接近的过分配对/曝光过度的图像和高级别的语义指导,可以提高尖端LLE模型的性能?在这里,我们提出了一种有效的语义对比的学习范例(即SCL-LLE)。除了现有的LLE智慧之外,它将图像增强任务施放为多任务联合学习,其中LLE被转换为对比学习,语义亮度一致性的三个约束,同时确保曝光,纹理和颜色一致性。 SCL-LLE允许LLE模型从未配对的阳性(常灯)/否定(过度/曝光),并使其与场景语义进行互动以正规化图像增强网络,但高级语义知识的相互作用并且在以前的方法中很少地研究了低级信号。培训易于获得的开放数据,广泛的实验表明,我们的方法超越了六个独立的交叉场景数据集的最先进的LLE模型。此外,讨论了SCL-LLE在极暗条件下有益于下游语义分割的潜力。源代码:https://github.com/linglix/sclle。
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随着预先训练模型的巨大成功,Pretrain-Then-Finetune范式已被广泛采用下游任务,以获得源代码的理解。但是,与昂贵的培训从头开始培训,如何将预先训练的模型从划痕进行有效地调整到新任务的训练模型尚未完全探索。在本文中,我们提出了一种桥接预先训练的模型和与代码相关任务的方法。我们利用语义保留的转换来丰富下游数据分集,并帮助预先接受的模型学习语义特征不变于这些语义上等效的转换。此外,我们介绍课程学习以易于努力的方式组织转换的数据,以微调现有的预先训练的模型。我们将我们的方法应用于一系列预先训练的型号,它们在源代码理解的任务中显着优于最先进的模型,例如算法分类,代码克隆检测和代码搜索。我们的实验甚至表明,在没有重量训练的代码数据上,自然语言预先训练的模型罗伯塔微调我们的轻质方法可以优于或竞争现有的代码,在上述任务中进行微调,如Codebert和Codebert和GraphCodebert。这一发现表明,代码预训练模型中仍有很大的改进空间。
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由于缺乏标签信息,异常检测是机器学习中的基本但具有挑战性的问题。在这项工作中,我们提出了一种新颖而强大的框架,称为SLA $ ^ 2 $ P,用于无监督的异常检测。在从原始数据中提取代表性嵌入后,我们将随机投影应用于特征,并将不同投影转换的特征视为属于不同的伪类。然后,我们在这些转换功能上培训一个分类器网络,以执行自我监督的学习。接下来,我们向变换特征添加对冲扰动,以减少预测标签的软MAX分数,并基于这些扰动特征对分类器的预测不确定性来降低预测标签和设计异常分数。我们的动机是,由于相对较小的数量和分散的异常模式,1)伪标签分类器的培训更集中学习正常数据的语义信息而不是异常数据; 2)正常数据的转换特征比异常的扰动更强大。因此,异常的扰动转化的特征不能良好分类,因此具有比正常样本的异常分数低。在图像,文本和固有的表格基准数据集上进行了广泛的实验,并表明SLA $ ^ 2 $ p实现了最先进的导致无监督的异常检测任务一致。
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以前的工作主要侧重于改善NLU任务的交叉传输,具有多语言预用编码器(MPE),或提高与伯特的监督机器翻译的性能。然而,探索了,MPE是否可以有助于促进NMT模型的交叉传递性。在本文中,我们专注于NMT中的零射频转移任务。在此任务中,NMT模型培训,只有一个语言对的并行数据集和搁置架MPE,然后它直接测试在零拍语言对上。我们为此任务提出了Sixt,一个简单而有效的模型。 SIXT利用了两阶段培训计划利用MPE,并进一步改进了解离编码器和容量增强的解码器。使用此方法,SIMPT显着优于MBart,这是一个用于NMT的预磨削的多语言编码器解码器模型,平均改善了14个源语言的零拍摄的任何英语测试集上的7.1 BLEU。此外,培训计算成本和培训数据较少,我们的模型在15个任何英语测试组上实现了比Criss和M2M-100,两个强大的多语言NMT基线更好的性能。
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Masked image modeling (MIM) performs strongly in pre-training large vision Transformers (ViTs). However, small models that are critical for real-world applications cannot or only marginally benefit from this pre-training approach. In this paper, we explore distillation techniques to transfer the success of large MIM-based pre-trained models to smaller ones. We systematically study different options in the distillation framework, including distilling targets, losses, input, network regularization, sequential distillation, etc, revealing that: 1) Distilling token relations is more effective than CLS token- and feature-based distillation; 2) An intermediate layer of the teacher network as target perform better than that using the last layer when the depth of the student mismatches that of the teacher; 3) Weak regularization is preferred; etc. With these findings, we achieve significant fine-tuning accuracy improvements over the scratch MIM pre-training on ImageNet-1K classification, using all the ViT-Tiny, ViT-Small, and ViT-base models, with +4.2%/+2.4%/+1.4% gains, respectively. Our TinyMIM model of base size achieves 52.2 mIoU in AE20K semantic segmentation, which is +4.1 higher than the MAE baseline. Our TinyMIM model of tiny size achieves 79.6% top-1 accuracy on ImageNet-1K image classification, which sets a new record for small vision models of the same size and computation budget. This strong performance suggests an alternative way for developing small vision Transformer models, that is, by exploring better training methods rather than introducing inductive biases into architectures as in most previous works. Code is available at https://github.com/OliverRensu/TinyMIM.
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