Synthesis of complex-valued InSAR data with a multi-task convolutional neural network

Convolutional neural network (CNN) based image steganalysis are increasingly popular because of their superiority in accuracy. The most straightforward way to employ CNN for image steganalysis is to learn a CNN-based classifier to distinguish whether secret messages have been embedded into an image. However, it is difficult to learn such a classifier because of the weak stego signals and the limited useful information. To address this issue, in this paper, a multi-task learning CNN is proposed. In addition to the typical use of CNN, learning a CNN-based classifier for the whole image, our multi-task CNN is learned with an auxiliary task of the pixel binary classification, estimating whether each pixel in an image has been modified due to steganography. To the best of our knowledge, we are the first to employ CNN to perform the pixel-level classification of such type. Experimental results have justified the effectiveness and efficiency of the proposed multi-task learning CNN.

Facial expression recognition and virtual animation character generation are crucial for animation production and human-computer interaction, but traditional models often perform poorly in complex scenes. This paper proposes a novel expression recognition and generation framework based on an improved Multi-Task Convolutional Neural Network (MTCNN), augmented by a High-Resolution Parallel Convolutional Network (HR-PCN) and Octave Convolution (OctConv). Specifically, HR-PCN enhances multi-scale feature extraction for facial keypoint detection, while OctConv improves frequency-aware representation learning. In terms of facial expression generation, Graph Convolutional Networks (GCNs) are adopted to model the semantic relationships between facial Action Units (AUs) and further enhanced with SE-ResNet50 for better spatial attention. The proposed MTCNN model was evaluated on the AFEW and CK+ datasets, achieving 89.70% and 93.50% accuracies, surpassing MTCNN’s 78.90% and 85.30% and SSD’s 85.40% and 90.10%. RMSE was reduced to 0.1 after 30 iterations, and inference time was kept within 40 ms/frame. For expression generation, the SE-ResNet50-GCN model attained a generation accuracy of up to 93.5%, significantly outperforming ResNet50-GCN (90.8%) and GCN (80.2%). These results validate the proposed framework’s effectiveness in improving both recognition accuracy and expression realism under complex conditions.

MP34-06 MACHINE LEARNING USING A MULTI-TASK CONVOLUTIONAL NEURAL NETWORKS CAN ACCURATELY ASSESS ROBOTIC SKILLS

The COVID-19 can be transmitted by air droplets, aerosols, and other carriers, the spread of the virus can be effectively prevented by wearing masks in public. Therefore, it is meaningful to identify whether a mask is worn in particular places. In this paper, a method based on multi-task convolutional neural networks (MTCNN) and MobileNet algorithms is proposed to implement mask recognition on human face. Firstly, MTCNN is used to detect facial contours. Then the output image is used to train MobileNet model. By comparing the extracted facial feature data, the human with mask or not can be marked. The method has been tested in a 1.8 GHz Intel Core machine with 160 × 160 static images. Average accuracy rate of 94.73% and detection speed of 1.9 s are achieved.

Accurate fault information is critical for optimal scheduling of production activities, improving system reliability, and reducing operation and maintenance costs. In recent years, many fault diagnosis methods for rolling element bearings have been developed based on deep learning. Most of them are totally data-driven and do not consider the domain knowledge that has been used in fault diagnosis for years. Meanwhile, operating conditions such as rotating speed and load that have great influence on vibration signals are also ignored. It may cause a decrease in accuracy when the bearing type or operating condition changes. To address these problems, this article proposes a rolling element bearing fault diagnosis and localization approach based on multitask convolutional neural network (CNN) with information fusion. In the proposed approach, domain knowledge, operating conditions, and vibration signals are fused into a three-dimensional input that can be processed well by CNN. Then, a multitask CNN with dynamic training rates is constructed to simultaneously accomplish two tasks, fault diagnosis and localization. Experimental results on two rolling element bearing test beds with different bearing types and operating conditions are presented and compared with existing state-of-the-art approaches to demonstrate the effectiveness and accuracy of the proposed approach.

Multi-task learning in Convolutional Neural Networks (CNNs) has led to remarkable success in a variety of applications of computer vision. Towards effective multi-task CNN architectures, recent studies automatically learn the optimal combinations of task-specific features at single network layers. However, they generally learn an unchanged operation of feature combination after training, regardless of the characteristic changes of task-specific features across different inputs. In this paper, we propose a novel Adaptive Feature Aggregation (AFA) layer for multi-task CNNs, in which a dynamic aggregation mechanism is designed to allow each task adaptively determines the degree to which the knowledge sharing or preserving between tasks is needed based on the characteristics of inputs. We introduce two types of aggregation modules to the AFA layer, which realize the adaptive feature aggregation by capturing the feature dependencies of different tasks along the channel and spatial axes, respectively. The AFA layer is a plug-and-play component with low parameter and computation overheads, and can be trained end-to-end along with backbone networks. For both pixel-level and image-level tasks, we empirically show that our approach substantially outperforms the previous state-of-the-art methods of multi-task CNNs. The code and models are available at https://github.com/zhenshen-mla/AFANet.

BackgroundSimultaneous dual-tracer positron emission tomography (PET) imaging can observe two molecular targets in a single scan, which is conducive to disease diagnosis and tracking. Since the signals emitted by different tracers are the same, it is crucial to separate each single tracer from the mixed signals. The current study proposed a novel deep learning-based method to reconstruct single-tracer activity distributions from the dual-tracer sinogram.MethodsWe proposed the Multi-task CNN, a three-dimensional convolutional neural network (CNN) based on a framework of multi-task learning. One common encoder extracted features from the dual-tracer dynamic sinogram, followed by two distinct and parallel decoders which reconstructed the single-tracer dynamic images of two tracers separately. The model was evaluated by mean squared error (MSE), multiscale structural similarity (MS-SSIM) index and peak signal-to-noise ratio (PSNR) on simulated data and real animal data, and compared to the filtered back-projection method based on deep learning (FBP-CNN).ResultsIn the simulation experiments, the Multi-task CNN reconstructed single-tracer images with lower MSE, higher MS-SSIM and PSNR than FBP-CNN, and was more robust to the changes in individual difference, tracer combination and scanning protocol. In the experiment of rats with an orthotopic xenograft glioma model, the Multi-task CNN reconstructions also showed higher qualities than FBP-CNN reconstructions.ConclusionsThe proposed Multi-task CNN could effectively reconstruct the dynamic activity images of two single tracers from the dual-tracer dynamic sinogram, which was potential in the direct reconstruction for real simultaneous dual-tracer PET imaging data in future.

No-reference stereoscopic image quality assessment using a multi-task CNN and registered distortion representation

Based on neural network and local binary pattern algorithm, this paper builds a lightweight artificial face recognition system on chip Firefly-RK3399, with high speed, strong robustness and high recognition accuracy. Our embedded artificial intelligent face recognition system mainly consists of face detection, feature extraction and recognition. Multi-task convolutional neural network (MTCNN) under the CaffeOnACL framework is utilized for face detection, and the local binary pattern (LBP) is applied as face recognition algorithm. Experiments illustrate that our artificial intelligent embedded face recognition system has high speed and accuracy, which is easy-carrying and of high commercial value as well.

Simultaneous monitoring of two comprehensive quality evaluation indexes of frozen-thawed beef meatballs using hyperspectral imaging and multi-task convolutional neural network

Recently, automatic vehicle identification system has great significance in practical life and with modern technology now widely available, the research on automatic vehicle recognition based on computer vision is becoming increasingly thorough and extensive. However, automatic vehicle identification also faces significant challenges, such as changes in lighting, weather conditions and distortion of captured images in natural road scenes. Since 2012, as a deep learning in image classification, the convolution neural network has become a major subject in many fields, so this study would focus on the vehicle identification in terms of the convolutional neural network. The Cars196 data set and an improved Convolutional Neural Network (CNN) network capable of multi-attribute recognition are applied to study the optimization network problem of the convolutional neutral network and to realize the multi-attribute classification and identification of automobile brands, models and colors. The data analysis shows that the improved CNN recognition network has a recognition accuracy in automatic vehicle recognition, but the overall recognition network is affected by many factors. According to the results of data analysis, in practice, alongside the improvement of traditional convolutional neural network, the improved new neural network structure should also be used for vehicle recognition, so as to improve the accuracy of vehicle identification to better serve the community.

Deep learning is one of the most popular technologies and research areas in machine learning. Convolutional Neural Networks (CNNs) are a typical artificial neural network underpinning deep learning. They have been used in many fields including image recognition, natural language process, and through games such as AlphaGo. A CNN has many advantages such as efficient feature extraction, the simplicity of data format required and the small number of (hyper-)parameters that are required. This paper focuses on a particular application of deep learning: crowd counting. To address this, we apply a Multi-task, Cascaded Convolutional Neural Network (MTCNN). Compared to other models, this model has a good performance and requires a shorter inference time, with shallower network structure and smaller size. In order to demonstrate the value and feasibility of the technology and provide a friendly operating environment for users, the application was realised on both the iOS and Android platforms. A web platform was also developed to visualize the real-time data using a Firebase server.

In order to solve the problem of poor real-time performance and low accuracy of a single detection target of common driver fatigue driving detection method based on facial features in practical applications, a fatigue driving detection method based on lightweight convolutional neural network is proposed. First, the driver's facial feature point data set is made through MTCNN (multi task convolutional neural network). Then the data set is used to train a lightweight convolutional neural network to detect the accurate feature point position of the eyes and mouth. Finally, the open and close state of the driver's eyes and mouth is judged based on the feature point coordinates. According to the open and closed state of the eyes and mouth of the continuous multi-frame image, the driver is judged to be in the state of fatigue. The experimental results show that the processing time of the single frame image by the algorithm is 23.3 millisecond; the single detection accuracy is up to 99.4%, and the detection accuracy of fatigue driving can reach 95%. The algorithm is better real-time performance and higher accuracy, so it has certain engineering significance and application prospects.

Hierarchical neural networks have been shown to be effective in learning representative image features and recognizing object classes. However, most existing networks combine the low/middle level cues for classification without accounting for any spatial structures. For applications such as understanding a scene, how the visual cues are spatially distributed in an image becomes essential for successful analysis. This paper extends the framework of deep neural networks by accounting for the structural cues in the visual signals. In particular, two kinds of neural networks have been proposed. First, we develop a multitask deep convolutional network, which simultaneously detects the presence of the target and the geometric attributes (location and orientation) of the target with respect to the region of interest. Second, a recurrent neuron layer is adopted for structured visual detection. The recurrent neurons can deal with the spatial distribution of visible cues belonging to an object whose shape or structure is difficult to explicitly define. Both the networks are demonstrated by the practical task of detecting lane boundaries in traffic scenes. The multitask convolutional neural network provides auxiliary geometric information to help the subsequent modeling of the given lane structures. The recurrent neural network automatically detects lane boundaries, including those areas containing no marks, without any explicit prior knowledge or secondary modeling.

ObjectiveWe implement 2 different multitask learning (MTL) techniques, hard parameter sharing and cross-stitch, to train a word-level convolutional neural network (CNN) specifically designed for automatic extraction of cancer data from unstructured text in pathology reports. We show the importance of learning related information extraction (IE) tasks leveraging shared representations across the tasks to achieve state-of-the-art performance in classification accuracy and computational efficiency.Materials and MethodsMultitask CNN (MTCNN) attempts to tackle document information extraction by learning to extract multiple key cancer characteristics simultaneously. We trained our MTCNN to perform 5 information extraction tasks: (1) primary cancer site (65 classes), (2) laterality (4 classes), (3) behavior (3 classes), (4) histological type (63 classes), and (5) histological grade (5 classes). We evaluated the performance on a corpus of 95 231 pathology documents (71 223 unique tumors) obtained from the Louisiana Tumor Registry. We compared the performance of the MTCNN models against single-task CNN models and 2 traditional machine learning approaches, namely support vector machine (SVM) and random forest classifier (RFC).ResultsMTCNNs offered superior performance across all 5 tasks in terms of classification accuracy as compared with the other machine learning models. Based on retrospective evaluation, the hard parameter sharing and cross-stitch MTCNN models correctly classified 59.04% and 57.93% of the pathology reports respectively across all 5 tasks. The baseline models achieved 53.68% (CNN), 46.37% (RFC), and 36.75% (SVM). Based on prospective evaluation, the percentages of correctly classified cases across the 5 tasks were 60.11% (hard parameter sharing), 58.13% (cross-stitch), 51.30% (single-task CNN), 42.07% (RFC), and 35.16% (SVM). Moreover, hard parameter sharing MTCNNs outperformed the other models in computational efficiency by using about the same number of trainable parameters as a single-task CNN.ConclusionsThe hard parameter sharing MTCNN offers superior classification accuracy for automated coding support of pathology documents across a wide range of cancers and multiple information extraction tasks while maintaining similar training and inference time as those of a single task–specific model.