This paper presents two deep learning models using a multi-perspective convolutional neural network (CNN) for classifying objects in the context of intelligent transportation systems (ITS). The proposed model categorizes objects accurately, enabling them to make well-informed decisions in multi-object (such as Persons, Trucks, Motorbikes, Cars, and Cyclists.) detection in complex scenarios for automotive applications. The custom backbone model is designed based on experimentation with the VGG backbone network based on the VGG backbone network, incorporating a multilayer prediction head and custom feature extraction blocks for classifying multiple objects in complex scenes. The model is to extract abstract features and features at multiple scales with a custom-designed feature extraction backbone with multiple blocks. The proposed models are lightweight and require fewer computational resources for high classification performance. The automotive publicly available dataset with 19800 images and labels has been used. Results show that when we experimented with the VGG backbone CNN model, the classification accuracy of 99.64% is achieved, and on the other hand, the classification accuracy of custom backbone CNN is 99.46%. The performance of the proposed custom model is also compared to those of pre-trained benchmark models. The experimental findings presented in this paper show that the proposed models achieve higher accuracy than the pre-trained models.
Convolutional Neural Networks have become an important tool for various Computer Vision tasks. Yet, increasing complexity of such architectures drives computational costs. To this end, we propose two measures to achieve similar classification results as state-of-the-art architectures while at the same time reducing model complexity significantly. Firstly, we describe a novel type of non-linear parameter-efficient morphological layers inspired by concepts that are well-known and widely used with convolutions. Secondly, we present a set of simple network architectures, organized as optimization framework, which is enhanced by neural architecture search and hyperparameter optimization. In experiments with hyperspectral remote sensing data, we demonstrate that the identified optimal morphological architecture produces results not only comparable with other architectures from the optimization framework, but also comparable or better than selected state-of-the-art neural network architectures for image classification. Depending on the performed task, the proposed optimized architecture requires up to 25 times fewer parameters than actual state-of-the-art networks.
We present FARA, a novel approach for fast approximation of RFD-like descriptors in the context of document retrieval systems. RFD-like descriptors are widely used for document representation, but their computation is expensive, especially for large document collections. Our method is a CPU-friendly gradient maps computation approximation with sequential memory access and integer-only calculations. There are three types of operations that we use: addition, subtraction, and absolute values. It allows us to effectively use SIMD extensions, resulting in an additional increase in the running speed. Experimental results demonstrate that FARA achieves the same accuracy as RFDoc descriptors and significantly reduces the computational overhead. The proposed approach achieves a twofold speed improvement of gradient maps computation and 25% acceleration of overall descriptor computing time compared to the most efficient RFDoc implementation.
The human olfactory bulb (OB), an important part of the brain responsible for the sense of smell, is a complex structure composed of multiple layers and cell types. Studying the OB morphological structure is essential for understanding the decline in olfactory function related to aging, neurodegenerative disorders, and other pathologies. Traditional microscopy methods in which slices are stained with solutions to contrast individual elements of the morphological structure are destructive. Non-destructive high-resolution technique is the X-ray phase-contrast tomography. However, manual segmentation of the reconstructed images are time-consuming due to large amount of data and prone to errors. U-Net-based model to optimize the segmentation of OB morphological structures, focusing specifically on glomeruli, in tomographic images of the human OB is proposed. The strategy to address overfitting and enhance the model's accuracy is described. This method addresses the challenges posed by complex limited data containing abundant details, similar grayscale levels between soft tissues, and blurry image details. Additionally, it successfully overcomes the limitations of a small dataset containing images with extremely dense point clouds, preventing the models from overfitting.
Nowadays, mobile robots solve various tasks realted to navigation in an unknown or changing environment. In such conditions, mapping the environment is crucial for mobile robot navigation. Conventionally, maps are built as 2D or 3D dense metric structures which require much memory for storage and much computational time for path planning, especially in large environments. Representing a map as a topological structure (i.e. a graph of locations) allows fast path planning with low memory consumption. In this paper, we present a method of real-time topological map building and updating from odometry measurements and local point clouds. The proposed method guarantees the topological graph connectivity and adds shortcuts to the graph to optimize paths. We tested our method in a simulated environment and measured efficiency of path planning in the obtained graphs. In all the tests, the SPL value exceeded 81%, with 100% success rate. The source code of our method is available at https://github.com/KirillMouraviev/simple_toposlam_model.
