Non-intrusive load monitoring (NILM), also known as energy disaggregation, is a blind source separation problem where a households aggregate electricity consumption is broken down into electricity usages of individual appliances. In this way, the cost and trouble of installing many measurement devices over numerous household appliances can be avoided, and only one device needs to be installed. The problem has been well-known since Hart's seminal paper in 1992, and recently significant performance improvements have been achieved by adopting deep networks. In this work, we focus on the idea that appliances have on/off states, and develop a deep network for further performance improvements. Specifically, we propose a subtask gated network that combines the main regression network with an on/off classification subtask network. Unlike typical multitask learning algorithms where multiple tasks simply share the network parameters to take advantage of the relevance among tasks, the subtask gated network multiply the main network's regression output with the subtask's classification probability. When standby-power is additionally learned, the proposed solution surpasses the state-of-theart performance for most of the benchmark cases. The subtask gated network can be very effective for any problem that inherently has on/off states.

The convolutional neural network (CNN)-based super-resolution (SR) has shown outstanding performance in the field of computer vision. The implementation of inference hardware for CNN-based SR has suffered from the intensive computation with severely unbalanced computation load among layers. Various light-weighted SR networks have been researched with little performance degradation. However, the hardware-efficient dataflow is also required to efficiently accelerate inference hardware within limited resources. In this paper, we propose the hardware-efficient dataflow of CNN-based SR that reduces computation load by increasing data reuse and increases process element (PE) utilization by balancing the computation load among layers for high throughput. In the proposed dataflow, row-wise pixels in the receptive field are computed by circularly shifting memory addresses to maximize data reuse. The partial convolution is exploited in a layer-based pipeline architecture to relieve intensive computation in a single pipeline stage. The delay-balancing with adjusting parallelism is employed for balancing computations precisely in the overall layers. Furthermore, the inference hardware of CNN-based SR is implemented for 4K ultrahigh definition at 60 fps on a field-programmable gate array (FPGA). For hardware-friendly computation, the quantization of activation and weight is adopted. The proposed hardware shows an average peak signalto-noise ratio of 36.42 dB in the Set-5 dataset with a memory usage of 53 KB and an average PE utilization of 76.7% in the overall layers. Thus, it achieves the lowest memory usage and highest PE utilization compared with other inference hardware for CNN-based SR.

We ask whether the neural network interpretation methods can be fooled via adversarial model manipulation, which is defined as a model fine-tuning step that aims to radically alter the explanations without hurting the accuracy of the original models, e.g., VGG19, ResNet50, and DenseNet121. By incorporating the interpretation results directly in the penalty term of the objective function for finetuning, we show that the state-of-the-art saliency map based interpreters, e.g., LRP, Grad-CAM, and SimpleGrad, can be easily fooled with our model manipulation. We propose two types of fooling, Passive and Active, and demonstrate such foolings generalize well to the entire validation set as well as transfer to other interpretation methods. Our results are validated by both visually showing the fooled explanations and reporting quantitative metrics that measure the deviations from the original explanations. We claim that the stability of neural network interpretation method with respect to our adversarial model manipulation is an important criterion to check for developing robust and reliable neural network interpretation method.

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