Computer Optics最新文献_第5页

Low-parameter method for delineation of agricultural fields in satellite images based on multi-temporal MSAVI2 data 基于多时相MSAVI2数据的卫星影像农田圈定低参数方法

IF 1

Computer Optics Pub Date : 2023-06-01 DOI: 10.18287/-6179-co-1235

M. A. Pavlova, V. Timofeev, D. Bocharov, D. Sidorchuk, A. L. Nurmukhametov, A. Nikonorov, M.S. Yarykina, I. Kunina, A. Smagina, M. Zagarev

{"title":"Low-parameter method for delineation of agricultural fields in satellite images based on multi-temporal MSAVI2 data","authors":"M. A. Pavlova, V. Timofeev, D. Bocharov, D. Sidorchuk, A. L. Nurmukhametov, A. Nikonorov, M.S. Yarykina, I. Kunina, A. Smagina, M. Zagarev","doi":"10.18287/-6179-co-1235","DOIUrl":"https://doi.org/10.18287/-6179-co-1235","url":null,"abstract":"This paper considers an issue of delineating agricultural fields in satellite images. In this task we follow a multi-temporal data approach. We show that on such data, good quality can be achieved using a simple low-parameter method. The method consists of a combination of a field detector and an edge detector. The field detection is based on an Otsu thresholding technique and for the edge detection we use a Canny detector. Facing a lack of available datasets and aiming to estimate the proposed algorithm, we prepared and published our dataset consisting of 18,859 expertly annotated fields using Sentinel-2 data. We implement one of the state-of-the-art deep-learning approaches and compare it with the proposed method on our dataset. The experiment shows the proposed simple multi-temporal algorithm to outperform the state-of-the-art instant data approach. This result confirms the importance of using multi-temporal data and for the first time demonstrates that the delineation problem can be solved at a lower cost without loss of quality. Our approach requires a significantly less amount of training data when compared with the NN-based one. The dataset of agricultural fields used in the work and the proposed algorithm implementation in Python are published in open access.","PeriodicalId":46692,"journal":{"name":"Computer Optics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88231992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Coupled-mode theory for resonant gratings with a varying period 变周期谐振光栅的耦合模理论

IF 1

Computer Optics Pub Date : 2023-06-01 DOI: 10.18287/2412-6179-co-1232

D. Bykov, E. Bezus, L. Doskolovich

引用次数: 1

Formation of features based on computational topology methods 基于计算拓扑方法的特征形成

IF 1

Computer Optics Pub Date : 2023-06-01 DOI: 10.18287/2412-6179-co-1190

S. Chukanov

{"title":"Formation of features based on computational topology methods","authors":"S. Chukanov","doi":"10.18287/2412-6179-co-1190","DOIUrl":"https://doi.org/10.18287/2412-6179-co-1190","url":null,"abstract":"The use of traditional methods of algebraic topology to obtain information about the shape of an object is associated with the problem of forming a small amount of information, namely, Betti numbers and Euler characteristics. The central tool for topological data analysis is the persistent homology method, which summarizes the geometric and topological information in the data using persistent diagrams and barcodes. Based on persistent homology methods, topological data can be analyzed to obtain information about the shape of an object. The construction of persistent barcodes and persistent diagrams in computational topology does not allow one to construct a Hilbert space with a scalar product. The possibility of applying the methods of topological data analysis is based on mapping persistent diagrams into a Hilbert space; one of the ways of such mapping is a method of constructing a persistence landscape. It has an advantage of being reversible, so it does not lose any information and has persistence properties. The paper considers mathematical models and functions for representing persistence landscape objects based on the persistent homology method. Methods for converting persistent barcodes and persistent diagrams into persistence landscape functions are considered. Associated with persistence landscape functions is a persistence landscape kernel that forms a mapping into a Hilbert space with a dot product. A formula is proposed for determining a distance between the persistence landscapes, which allows the distance between images of objects to be found. The persistence landscape functions map persistent diagrams into a Hilbert space. Examples of determining the distance between images based on the construction of persistence landscape functions for these images are given. Representations of topological characteristics in various models of computational topology are considered. Results for one-parameter persistence modules are extended onto multi-parameter persistence modules.","PeriodicalId":46692,"journal":{"name":"Computer Optics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81099383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Modified prism methods for measuring the refractive index of solid and liquid substances 测量固体和液体物质折射率的改进棱镜法

IF 1

Computer Optics Pub Date : 2023-06-01 DOI: 10.18287/2412-6179-co-1230

A. Yurin, G. Vishnyakov, V. Minaev

引用次数: 0

Method for detecting road defects using images obtained from unmanned aerial vehicles 使用从无人驾驶飞行器获得的图像检测道路缺陷的方法

IF 1

Computer Optics Pub Date : 2023-06-01 DOI: 10.18287/2412-6179-co-1209

M. Kataev, E. Kartashov, V. D. Avdeenko, Evgeny Yurievich, Kartashov

引用次数: 1

A Fourier-invariant squared Laguerre-Gaussian vortex beam 傅里叶不变的平方拉盖尔高斯涡旋光束

IF 1

Computer Optics Pub Date : 2023-06-01 DOI: 10.18287/2412-6179-co-1228

E. Kozlova, A. Savelyeva, A. Kovalev, V. Kotlyar

引用次数: 1

Using a lightweight Siamese neural network for generating a feature vector in a vascular authentication system 使用轻量级的Siamese神经网络在血管认证系统中生成特征向量

IF 1

Computer Optics Pub Date : 2023-06-01 DOI: 10.18287/2412-6179-co-1204

D. Prozorov, A. Zemtsov

{"title":"Using a lightweight Siamese neural network for generating a feature vector in a vascular authentication system","authors":"D. Prozorov, A. Zemtsov","doi":"10.18287/2412-6179-co-1204","DOIUrl":"https://doi.org/10.18287/2412-6179-co-1204","url":null,"abstract":"The article analyzes the possibility of using a Siamese convolutional neural network to solve the problem of vascular authentication on an embedded hardware platform with limited computing resources (Orange Pi One). The authors give a brief review of modern methods for calculating image feature vectors used in the tasks of classifying, comparing or searching for images by content: based on variational series (histograms), local descriptors, singular point descriptors, descriptors based on hash functions, neural network descriptors. They suggest using the architecture of a biometric authentication system (BAS) based on images of palms in the visible and near-IR spectra based on a Siamese convolutional neural network. The developed software solution allows using the Siamese neural network in the \"full network\" (both symmetrical channels of the neural network are used) and \"half of the neural network\" (only one channel is used) modes to reduce the time for comparing biometric data vectors - images of the palms of registered BAS users. The authors demonstrate advantages of the neural network features: universality, scalability and competitiveness, including on embedded hardware and software solutions with limited computing resources without graphics accelerators. The studies have shown that using the Siamese neural network, the \"overall accuracy\" of palm image classification can be improved from 0.929 to 0.968 when compared with the image vectorization method based on a perceptual hash, while showing a comparable authentication time for individuals registered in BAS. In the experiments, the authors use a database of 2,000 images for 400 people.","PeriodicalId":46692,"journal":{"name":"Computer Optics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78003635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Huge spikes and dips of the orbital angular momentum in structured Laguerre-Gaussian beams resistant to simple astigmatism 抗简单散光的结构拉盖尔-高斯光束中轨道角动量的巨大尖峰和低谷

IF 1

Computer Optics Pub Date : 2023-06-01 DOI: 10.18287/2412-6179-co-1243

A. Volyar, E. Abramochkin, Y. Akimova, M. Bretsko

{"title":"Huge spikes and dips of the orbital angular momentum in structured Laguerre-Gaussian beams resistant to simple astigmatism","authors":"A. Volyar, E. Abramochkin, Y. Akimova, M. Bretsko","doi":"10.18287/2412-6179-co-1243","DOIUrl":"https://doi.org/10.18287/2412-6179-co-1243","url":null,"abstract":"The article investigated conditions for shaping astigmatic-invariant structured Laguerre-Gaussian (LG) beams in the case of simple astigmatism. We have theoretically and experimentally confirmed that the conditions of astigmatic invariance are that the q-phase parameter of the structured LG (sLG) beam is equal to the arctangent of the ratio of the Rayleigh length z0 to the focal length fcyl of a cylindrical lens for a single amplitude parameter of epsilon;=1. For the rest amplitude parameter values, epsilon;NotEqual;1, the astigmatic invariance condition is set by the equality of the orbital angular momenta (OAM) of structured sLG and astigmatic-invariant sLG (asLG) beams. We have also found sharp spikes and dips of the OAM in astigmatic asLG beams in the region where OAM turns into zero. The height and depth of these spikes and dips significantly exceed the maximum and minimum OAM values in the conventional structured sLG beams. It has been shown that the occurrence of spikes and dips of the OAM is caused by a radical restructuring of the LG mode spectra in the form of their strong ordering. Theoretical calculations, accompanied by a computer simulation, and an experiment agree well with each other.","PeriodicalId":46692,"journal":{"name":"Computer Optics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90357966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Laser beam shaping in an apodizer with a rectangular serrated aperture 具有矩形锯齿状孔径的射光器中的激光束整形

IF 1

Computer Optics Pub Date : 2023-06-01 DOI: 10.18287/2412-6179-co-1219

I.M. Sizova

引用次数: 0

Development and research of a neural network alternate incremental learning algorithm 神经网络交替增量学习算法的开发与研究

IF 1

Computer Optics Pub Date : 2023-06-01 DOI: 10.18287/2412-6179-co-1203

A. Orlov, E. S. Abramova

{"title":"Development and research of a neural network alternate incremental learning algorithm","authors":"A. Orlov, E. S. Abramova","doi":"10.18287/2412-6179-co-1203","DOIUrl":"https://doi.org/10.18287/2412-6179-co-1203","url":null,"abstract":"In this paper, the relevance of developing methods and algorithms for neural network incremental learning is shown. Families of incremental learning techniques are presented. A possibility of using the extreme learning machine for incremental learning is assessed. Experiments show that the extreme learning machine is suitable for incremental learning, but as the number of training examples increases, the neural network becomes unsuitable for further learning. To solve this problem, we propose a neural network incremental learning algorithm that alternately uses the extreme learning machine to correct the only output layer network weights (operation mode) and the backpropagation method (deep learning) to correct all network weights (sleep mode). During the operation mode, the neural network is assumed to produce results or learn from new tasks, optimizing its weights in the sleep mode. The proposed algorithm features the ability for real-time adaption to changing external conditions in the operation mode. The effectiveness of the proposed algorithm is shown by an example of solving the approximation problem. Approximation results after each step of the algorithm are presented. A comparison of the mean square error values when using the extreme learning machine for incremental learning and the developed algorithm of neural network alternate incremental learning is made.","PeriodicalId":46692,"journal":{"name":"Computer Optics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84938839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2