With an ever-growing number of parameters defining increasingly complex networks, Deep Learning has led to several breakthroughs surpassing human performance. As a result, data movement for these millions of model parameters causes a growing imbalance known as the memory wall. Neuromorphic computing is an emerging paradigm that confronts this imbalance by performing computations directly in analog memories. On the software side, the sequential Backpropagation algorithm prevents efficient parallelization and thus fast convergence. A novel method, Direct Feedback Alignment, resolves inherent layer dependencies by directly passing the error from the output to each layer. At the intersection of hardware/software co-design, there is a demand for developing algorithms that are tolerable to hardware nonidealities. Therefore, this work explores the interrelationship of implementing bio-plausible learning in-situ on neuromorphic hardware, emphasizing energy, area, and latency constraints. Using the benchmarking framework DNN+NeuroSim, we investigate the impact of hardware nonidealities and quantization on algorithm performance, as well as how network topologies and algorithm-level design choices can scale latency, energy and area consumption of a chip. To the best of our knowledge, this work is the first to compare the impact of different learning algorithms on Compute-In-Memory-based hardware and vice versa. The best results achieved for accuracy remain Backpropagation-based, notably when facing hardware imperfections. Direct Feedback Alignment, on the other hand, allows for significant speedup due to parallelization, reducing training time by a factor approaching N for N-layered networks.

In deep neural networks (DNNs), there are a huge number of weights and multiply-and-accumulate (MAC) operations. Accordingly, it is challenging to apply DNNs on resource-constrained platforms, e.g., mobile phones. Quantization is a method to reduce the size and the computational complexity of DNNs. Existing quantization methods either require hardware overhead to achieve a non-uniform quantization or focus on model-wise and layer-wise uniform quantization, which are not as fine-grained as filter-wise quantization. In this paper, we propose a class-based quantization method to determine the minimum number of quantization bits for each filter or neuron in DNNs individually. In the proposed method, the importance score of each filter or neuron with respect to the number of classes in the dataset is first evaluated. The larger the score is, the more important the filter or neuron is and thus the larger the number of quantization bits should be. Afterwards, a search algorithm is adopted to exploit the different importance of filters and neurons to determine the number of quantization bits of each filter or neuron. Experimental results demonstrate that the proposed method can maintain the inference accuracy with low bit-width quantization. Given the same number of quantization bits, the proposed method can also achieve a better inference accuracy than the existing methods.

Deep neural networks (DNNs) have successfully been applied in many fields in the past decades. However, the increasing number of multiply-and-accumulate (MAC) operations in DNNs prevents their application in resource-constrained and resource-varying platforms, e.g., mobile phones and autonomous vehicles. In such platforms, neural networks need to provide acceptable results quickly and the accuracy of the results should be able to be enhanced dynamically according to the computational resources available in the computing system. To address these challenges, we propose a design framework called SteppingNet. SteppingNet constructs a series of subnets whose accuracy is incrementally enhanced as more MAC operations become available. Therefore, this design allows a trade-off between accuracy and latency. In addition, the larger subnets in SteppingNet are built upon smaller subnets, so that the results of the latter can directly be reused in the former without recomputation. This property allows SteppingNet to decide on-the-fly whether to enhance the inference accuracy by executing further MAC operations. Experimental results demonstrate that SteppingNet provides an effective incremental accuracy improvement and its inference accuracy consistently outperforms the state-of-the-art work under the same limit of computational resources.

The last decade has witnessed the breakthrough of deep neural networks (DNNs) in many fields. With the increasing depth of DNNs, hundreds of millions of multiply-and-accumulate (MAC) operations need to be executed. To accelerate such operations efficiently, analog in-memory computing platforms based on emerging devices, e.g., resistive RAM (RRAM), have been introduced. These acceleration platforms rely on analog properties of the devices and thus suffer from process variations and noise. Consequently, weights in neural networks configured into these platforms can deviate from the expected values, which may lead to feature errors and a significant degradation of inference accuracy. To address this issue, in this paper, we propose a framework to enhance the robustness of neural networks under variations and noise. First, a modified Lipschitz constant regularization is proposed during neural network training to suppress the amplification of errors propagated through network layers. Afterwards, error compensation is introduced at necessary locations determined by reinforcement learning to rescue the feature maps with remaining errors. Experimental results demonstrate that inference accuracy of neural networks can be recovered from as low as 1.69% under variations and noise back to more than 95% of their original accuracy, while the training and hardware cost are negligible.

对自然和人制过程的研究通常会导致长时间有序值的长序列，也就是时间序列（TS）。这样的过程通常由多个状态组成，例如机器的操作模式，使观测过程中的状态变化会导致测量值形状的分布变化。时间序列分割（TSS）试图发现TS事后的这种变化，以推断数据生成过程的变化。通常将TSS视为无监督的学习问题，目的是识别某些统计属性可区分的细分。 TSS的当前算法要求用户设置依赖域的超参数，对TS值分布进行假设或可检测更改的类型，以限制其适用性。常见的超参数是段均匀性和变更点的数量的度量，对于每个数据集，这尤其难以调节。我们提出了TSS的一种新颖，高度准确，无参数和域的无义方法的方法。扣子分层将TS分为两个部分。更改点是通过训练每个可能的拆分点的二进制TS分类器来确定的，并选择最能识别从任何一个分区的子序列的一个拆分。 CLASP使用两种新颖的定制算法从数据中学习了其主要的两个模型参数。在我们使用115个数据集的基准测试的实验评估中，我们表明，扣子优于准确性，并且可以快速且可扩展。此外，我们使用几个现实世界的案例研究强调了扣子的特性。

图主直觉是一个短时间序列，在较大的时间序列中重复自身大致相同。这样的主题通常代表隐藏的结构，例如心电图记录中的心跳或脑电图中的睡眠纺锤体。主题发现（MD）是在给定输入系列中找到此类主题的任务。由于有不同的定义，因此存在许多算法。作为中心参数，它们都采用了基序的长度L和图案发生之间的最大距离R。但是，实际上，R的合适值很难确定前期，并且发现的图案显示出很高的可变性。设置错误的输入值将导致一个与噪声无法区分的主题。因此，使用这些方法找到一个有趣的主题需要广泛的试用和错误。我们对MD问题提出了不同的方法。我们将k- motiflet定义为长度为l的基序的精确k出现，其最大成对距离是最小的。这将MD问题颠倒了：我们的中心参数不是距离阈值r，而是主题集的所需尺寸K，我们显示的更直观且易于设置。基于此定义，我们提出了用于查找K-单体并分析其复杂性的精确和近似算法。为了进一步缓解我们的方法的使用，我们描述了扩展，以自动确定其输入参数的正确/合适值。因此，第一次提取有意义的主题集在没有任何A-Priori知识的情况下变得可行。通过评估现实世界的用例并将其与4种最先进的MD算法进行比较，我们表明我们提出的算法在定量上是（a）较高的，在较高的相似性上找到较大的基序集，（b）在质量上更好，导致，导致更清晰，更易于解释主题，（c）的运行时间最低。

我们介绍了一种基于辐射场接近基于图像的3D重建的新方法。体积重建的问题被制定为非线性最小二乘问题，并且在不使用神经网络的情况下明确解决。这使得能够使用具有比通常用于神经网络的更高收敛速率的求解器，并且在收敛之前需要更少的迭代。使用体素网格表示卷，其中场景被环境映射的层次结构包围。这使得可以获得前景和背景的360 {\ DEG}场景的清洁重建。来自众所周知的基准套房的许多合成和实际场景是以最先进的方法的质量成功重建，但在显着降低的重建时期。

特征选择是数据科学流水线的重要步骤，以减少与大型数据集相关的复杂性。虽然对本主题的研究侧重于优化预测性能，但很少研究在特征选择过程的上下文中调查稳定性。在这项研究中，我们介绍了重复的弹性网技术（租金）进行特色选择。租金使用具有弹性净正常化的广义线性模型的集合，每个训练都培训了训练数据的不同子集。该特征选择基于三个标准评估所有基本模型的重量分布。这一事实导致选择具有高稳定性的特征，从而提高最终模型的稳健性。此外，与已建立的特征选择器不同，租金提供了有关在训练期间难以预测的数据中难以预测的对象的模型解释的有价值信息。在我们的实验中，我们在八个多变量数据集中对六个已建立的特征选择器进行基准测试，用于二进制分类和回归。在实验比较中，租金在预测性能和稳定之间展示了均衡的权衡。最后，我们强调了租金的额外解释价值与医疗保健数据集的探索性后HOC分析。