Tsubasa Minematsu

Tsubasa Minematsu


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 March 2022 in Multimedia Tools and Applications
Verified
Journal Article
Open access
PDF file
AGAhmed Gomaa
Ahmed Gomaa
TMTsubasa Minematsu
Tsubasa Minematsu
MAMoataz M. Abdelwahab
Moataz M. Abdelwahab
Mohammed Abo-ZahhadMohammed Abo-Zahhad
Mohammed Abo-Zahhad
RTRin-ichiro Taniguchi
Rin-ichiro Taniguchi
Automatic detection and counting of vehicles in a video is a challenging task and has become a key application area of traffic monitoring and management. In this paper, an efficient real-time approach for the detection and counting of moving vehicles is presented based on YOLOv2 and features point motion analysis. The work is based on synchronous vehicle features detection and tracking to achieve accurate counting results. The proposed strategy works in two phases; the first one is vehicle detection and the second is the counting of moving vehicles. Different convolutional neural networks including pixel by pixel classification networks and regression networks are investigated to improve the detection and counting decisions. For initial object detection, we have utilized state-of-the-art faster deep learning object detection algorithm YOLOv2 before refining them using K-means clustering and KLT tracker. Then an efficient approach is introduced using temporal information of the detection and tracking feature points between the framesets to assign each vehicle label with their corresponding trajectories and truly counted it. Experimental results on twelve challenging videos have shown that the proposed scheme generally outperforms state-of-the-art strategies. Moreover, the proposed approach using YOLOv2 increases the average time performance for the twelve tested sequences by 93.4% and 98.9% from 1.24 frames per second achieved using Faster Region-based Convolutional Neural Network (F R-CNN ) and 0.19 frames per second achieved using the background subtraction based CNN approach (BS-CNN ), respectively to 18.7 frames per second.

22 October 2019 in Sensors
Verified
Journal Article
Open access
PDF file
AGAhmed Gomaa
Ahmed Gomaa
MAMoataz M. Abdelwahab
Moataz M. Abdelwahab
Mohammed Abo-ZahhadMohammed Abo-Zahhad
Mohammed Abo-Zahhad
TMTsubasa Minematsu
Tsubasa Minematsu
RTRin-ichiro Taniguchi
Rin-ichiro Taniguchi
Automatic vehicle detection and counting are considered vital in improving traffic control and management. This work presents an effective algorithm for vehicle detection and counting in complex traffic scenes by combining both convolution neural network (CNN) and the optical flow feature tracking-based methods. In this algorithm, both the detection and tracking procedures have been linked together to get robust feature points that are updated regularly every fixed number of frames. The proposed algorithm detects moving vehicles based on a background subtraction method using CNN. Then, the vehicle’s robust features are refined and clustered by motion feature points analysis using a combined technique between KLT tracker and K-means clustering. Finally, an efficient strategy is presented using the detected and tracked points information to assign each vehicle label with its corresponding one in the vehicle’s trajectories and truly counted it. The proposed method is evaluated on videos representing challenging environments, and the experimental results showed an average detection and counting precision of 96.3% and 96.8%, respectively, which outperforms other existing approaches.

8 June 2018 in Journal of Imaging
Verified
Journal Article
Open access
PDF file
TMTsubasa Minematsu
Tsubasa Minematsu
ASAtsushi SHIMADA
Atsushi SHIMADA
HUHideaki Uchiyama
Hideaki Uchiyama
RTRin-Ichiro Taniguchi
Rin-Ichiro Taniguchi
Deep neural network-based (DNN-based) background subtraction has demonstrated excellent performance for moving object detection. The DNN-based background subtraction automatically learns the background features from training images and outperforms conventional background modeling based on handcraft features. However, previous works fail to detail why DNNs work well for change detection. This discussion helps to understand the potential of DNNs in background subtraction and to improve DNNs. In this paper, we observe feature maps in all layers of a DNN used in our investigation directly. The DNN provides feature maps with the same resolution as that of the input image. These feature maps help to analyze DNN behaviors because feature maps and the input image can be simultaneously compared. Furthermore, we analyzed important filters for the detection accuracy by removing specific filters from the trained DNN. From the experiments, we found that the DNN consists of subtraction operations in convolutional layers and thresholding operations in bias layers and scene-specific filters are generated to suppress false positives from dynamic backgrounds. In addition, we discuss the characteristics and issues of the DNN based on our observation.

17 July 2024 in IEEE Access
Verified
Journal Article
Open access
SLSukrit Leelaluk
Sukrit Leelaluk
CTCheng Tang
Cheng Tang
TMTsubasa Minematsu
Tsubasa Minematsu
YTYuta Taniguchi
Yuta Taniguchi
FOFumiya Okubo
Fumiya Okubo
ASAtsushi SHIMADA
Atsushi SHIMADA
Student performance prediction was deployed to predict learning performance to identify at-risk students and provide interventions for them. However, prediction models should also consider external factors along with learning activities, such as course duration. Thus, we aim to distinguish the difference factor between the time dimension (duration of the course) and the feature dimension (students’ learning activities) by attention weights to provide helpful information and improve predictions of student performance. In this study, we introduce Attention-Based Artificial Neural Network (Attn-ANN), a novel model in educational data mining. The Attn-ANN combines attention weighting on the time and feature dimensions to examine the significance of lectures and learning activities and makes predictions by visualizing attention weight. We found that the Attn-ANN had a better area under the curve scores than conventional algorithms, and the attention mechanism allowed models to focus on input selectively. Incorporating the attention weighting of both the time and feature dimensions improved the prediction performance in an ablation study. Finally, we investigated and analyzed the model’s decision, finding that the Attn-ANN may be able to create synergy in real-world scenarios between the Attn-ANN’s predictions and instructors’ expertise, which underscores a novel contribution to engineering applications for interventions for at-risk students.

1 September 2019
Verified
Conference Paper
Closed access
TMTsubasa Minematsu
Tsubasa Minematsu
ASAtsushi SHIMADA
Atsushi SHIMADA
RTRin-Ichiro Taniguchi
Rin-Ichiro Taniguchi
Recently, background subtraction based on deep convolutional neural networks has demonstrated excellent performance in change detection tasks. However, most of the reported approaches require pixel-level label images for training the networks. To reduce the cost of rendering pixel-level annotation data, weakly supervised learning approaches using frame-level labels have been proposed. These labels indicate if a target class is present. Frame-level supervised learning is challenging because we cannot use location information for training the networks. Therefore, some constraints are introduced for guiding foreground locations. Previous works exploit prior information on foreground sizes and shapes. In this work, we propose two constraints for weakly supervised background subtraction networks. Our constraints use binary mask images generated by simple background subtraction. Unlike previous works, our approach does not require prior information on foreground sizes and shapes. Moreover, our constraints are more suitable for change detection tasks. We also present an experiment verifying that our constraints can improve foreground detection accuracy compared to other methods, which do not include them.

31 December 2017
Verified
Book Chapter
Closed access
PDF file
TMTsubasa Minematsu
Tsubasa Minematsu
ASAtsushi SHIMADA
Atsushi SHIMADA
HUHideaki Uchiyama
Hideaki Uchiyama
RTRin-Ichiro Taniguchi
Rin-Ichiro Taniguchi