Nec Corporation

Dongjin Song

Haifeng Chen

Yuncong Chen

Cristian Lumezanu

Wei Cheng

Takehiko Mizoguchi

Guofei Jiang

Renqiang Min

Eric Cosatto

LuAn Tang

Bo Zong

Wenchao Yu

Jingchao Ni

Wei Zhu

Bo Dong

Ning Xia

Yao Qin

Takehiko Mizuguchi

Xuchao Zhang

Shuchu Han

Tan Yan

Xinyang Feng

Tingyang Xu

Hao Yuan

Xiaoyuan Liang

Jurijs Nazarovs

Chuxu Zhang

Methods and systems for training a neural network include collecting model exemplar information from edge devices, each model exemplar having been trained using information local to the respective edge devices. The collected model exemplar information is aggregated together using federated averaging. Global model exemplars are trained using federated constrained clustering. The trained global exemplars are transmitted to respective edge devices.

Federated learning for anomaly detection

Edge-side federated learning for anomaly detection

A method classifies missing labels. The method computes, using a neural network model trained on training data, rank-based statistics of a feature of a time series segment to attempt to select two candidate labels from the training data that the segment most likely belongs to. The method classifies the segment using k-NN-based classification applied to the training data, responsive to the two candidate labels being present in the training data. The method classifies the segment by hypothesis testing, responsive to only one candidate label being present in the training data. The method classifies the segment into a class with higher values of the rank-based statistics from among a plurality of classes with different values of the rank-based statistics, responsive to no candidate labels being present in the training data. The method corrects a prediction by an applicable one of the classifying steps by majority voting with time windows.

Ordinal time series classification with missing information

Methods and systems of training and using a neural network model include training a time series embedding model and a text embedding model with unsupervised clustering to translate time series and text, respectively, to a shared latent space. The time series embedding model and the text embedding model are further trained using semi-supervised clustering that samples training data pairs of time series information and associated text for annotation.

Embedding multi-modal time series and text data

A method for multivariate time series prediction is provided. Each time series from among a batch of multiple driving time series and a target time series is decomposed into a raw component, a shape component, and a trend component. For each decomposed component, select a driving time series relevant thereto from the batch and obtain hidden features of the selected driving time series, by applying the batch to an input attention-based encoder of an Ensemble of Clustered dual-stage attention-based Recurrent Neural Networks (EC-DARNNS). Automatically cluster the hidden features in a hidden space using a temporal attention-based decoder of the EC-DARNNS. Each Clustered dual-stage attention-based RNN in the Ensemble is dedicated and applied to a respective one of the decomposed components. Predict a respective value of one or more future time steps for the target series based on respective prediction outputs for each of the decomposed components by the EC-DARNNS.

Ensemble of clustered dual-stage attention-based recurrent neural networks for multivariate time series prediction

Systems and methods for updating a classification model of a neural network. The methods include selecting, as a set of landmarks, a limited number of data from a set of historical data used to train a classification model. Additionally, the methods generate new training data from recently collected data. Further, the methods update the classification model with the new training data and the set of landmarks to obtain an updated classification model having a loss function configured to capture similarities in the new training data and remember similarities in the historical data represented by the set of landmarks within a predefined tolerance.

Landmark-based classification model updating

Systems and methods for predicting system device failure are provided. The method includes representing device failure related data associated with the devices from a predetermined domain by temporal graphs for each of the devices. The method also includes extracting vector representations based on temporal graph features from the temporal graphs that capture both temporal and structural correlation in the device failure related data. The method further includes predicting, based on the vector representations and device failure related metrics in the predetermined domain, one or more of the devices that is expected to fail within a predetermined time.

Performance prediction from communication data

Methods and systems for detecting and correcting anomalies includes generating historical binary codes from historical time series segments. The historical time series segments are each made up of measurements from respective sensors. A latest binary code is generated from a latest time series segment. It is determined that the latest time series segment represents anomalous behavior, based on a comparison of the latest binary code to the historical binary codes. The sensors are ranked, based on a comparison of time series data of the sensors in the latest time series segment to respective time series data of the historical time series, to generate a sensor ranking. A corrective action is performed responsive to the detected anomaly, prioritized according to the sensor ranking.

Sensor attribution for anomaly detection

Systems and methods for detecting anomaly in video data are provided. The system includes a generator that receives past video frames and extracts spatio-temporal features of the past video frames and generates frames. The generator includes fully convolutional transformer based generative adversarial networks (FCT-GANs). The system includes an image discriminator that discriminates generated frames and real frames. The system also includes a video discriminator that discriminates generated video and real video. The generator trains a fully convolutional transformer network (FCTN) model and determines an anomaly score of at least one test video based on a prediction residual map from the FCTN model.

Fully convolutional transformer based generative adversarial networks

A system for cross-modal data retrieval is provided that includes a neural network having a time series encoder and text encoder which are jointly trained using an unsupervised training method which is based on a loss function. The loss function jointly evaluates a similarity of feature vectors of training sets of two different modalities of time series and free-form text comments and a compatibility of the time series and the free-form text comments with a word-overlap-based spectral clustering method configured to compute pseudo labels for the unsupervised training method. The computer processing system further includes a database for storing the training sets with feature vectors extracted from encodings of the training sets. The encodings are obtained by encoding a training set of the time series using the time series encoder and encoding a training set of the free-form text comments using the text encoder.

Word-overlap-based clustering cross-modal retrieval

Methods and systems for detecting and correcting anomalies include comparing a new time series segment, generated by a sensor in a cyber-physical system, to previous time series segments of the sensor to generate a similarity measure for each previous time series segment. It is determined that the new time series represents anomalous behavior based on the similarity measures. A corrective action is performed on the cyber-physical system to correct the anomalous behavior.

Anomaly detection using deep learning on time series data

Systems and methods for implementing dynamic graph analysis (DGA) to detect anomalous network traffic are provided. The method includes processing communications and profile data associated with multiple devices to determine dynamic graphs. The method includes generating features to model temporal behaviors of network traffic generated by the multiple devices based on the dynamic graphs. The method also includes formulating a list of prediction results for sources of the anomalous network traffic from the multiple devices based on the temporal behaviors.

Dynamic transaction graph analysis

Systems and methods for anomaly detection are provided. The method includes structuring a multi-channel spatial-temporal sequence as a four-dimensional array. The method also includes decomposing the four-dimensional array to form a low-rank component representing a background signal and a residual component representing anomalies for each time point of the multi-channel spatial-temporal sequence. The method further includes determining a sequence of anomaly maps by stacking the residual components at all time points together. Anomalies are identified based on the sequence of anomaly maps.

Background suppression for anomaly detection

A method is provided. Intermediate audio features are generated from respective segments of an input acoustic time series for a same scene. Using a nearest neighbor search, respective segments of the input acoustic time series are classified based on the intermediate audio features to generate a final intermediate feature as a classification for the input acoustic time series. Each respective segment corresponds to a respective different acoustic window. The generating step includes learning the intermediate audio features from Multi-Frequency Cepstral Component (MFCC) features extracted from the input acoustic time series, dividing the same scene into the different windows having varying MFCC features, and feeding the MFCC features of each window into respective LSTM units such that a hidden state of each respective LSTM unit is passed through an attention layer to identify feature correlations between hidden states at different time steps corresponding to different ones of the different windows.

Audio scene recognition using time series analysis

Methods and systems for detecting and correcting anomalies include ranking sensors in a cyber-physical system according to a degree of influence each sensor has on a measured performance indicator in the cyber-physical system. An anomaly is detected in the cyber-physical system based on the measured performance indicator. A corrective action is performed responsive to the detected anomaly, prioritized according to sensor rank.

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Princeton, NJ, United States of America

Dongjin Song