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Keywords = complex valued b-metric space

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16 pages, 3019 KiB  
Article
Machine Learning-Based Morphological Classification and Diversity Analysis of Ornamental Pumpkin Seeds
by Sıtkı Ermiş, Uğur Ercan, Aylin Kabaş, Önder Kabaş and Georgiana Moiceanu
Foods 2025, 14(9), 1498; https://doi.org/10.3390/foods14091498 - 25 Apr 2025
Viewed by 884
Abstract
Ornamental pumpkin (Cucurbita pepo L. var. ovifera) seeds are highly morphologically variable, and their classification is hence a complex task for the seed industry. Efficient and accurate classification is critical for agricultural production, breeding programs, and seed sorting for commerce. This [...] Read more.
Ornamental pumpkin (Cucurbita pepo L. var. ovifera) seeds are highly morphologically variable, and their classification is hence a complex task for the seed industry. Efficient and accurate classification is critical for agricultural production, breeding programs, and seed sorting for commerce. This study employs machine learning models—Random Forest (RF), LightGBM, and k-Nearest Neighbors (KNN)—to classify ornamental pumpkin seeds based on their morphological (mass, elongation, width, thickness) and colorimetric characteristics (L*, a*, b* values from CIELAB color space). Prior to model training, the data set was preprocessed through normalization and balancing to enhance classification performance. In this study, six different types of ornamental pumpkin seeds were used, with a total of 900 (150 each of SDE0619, SDE1020, SDE1620, SDE2621, SDE4521, and SDE7721). The classification performance of the models was evaluated using different metrics, such as Accuracy, Balanced Accuracy, Precision, Recall, F1 Score, Matthews Correlation Coefficient (MCC), and Cohen’s Kappa. Among the tested models, the RF model performed best, with Accuracy of 0.959, Balanced Accuracy of 0.961, Precision (Macro) of 0.962, Recall (Macro) of 0.961, F1 Score (Macro) of 0.961, MCC of 0.951, and Cohen’s Kappa of 0.951. In contrast, the worst classification performance of the tested models was with the KNN model across all the evaluation metrics. These outcomes reflect the potential of machine learning-based approaches for seed classification automation, error minimization in seed classification, and maximization of efficiency in the seed industry. The high classification performance of the Random Forest model with 95.9% accuracy and 0.951 MCC value shows that artificial intelligence-based automatic classification of ornamental pumpkin seeds according to their morphological and colorimetric characteristics can make significant contributions to the seed industry, while the integration of this approach into seed sorting and quality determination processes can enable the creation of effective breeding schemes for optimum seed selection by maximizing the accuracy of agricultural processes. Full article
(This article belongs to the Special Issue Artificial Intelligence (AI) and Machine Learning for Foods)
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13 pages, 1956 KiB  
Article
A Multi-Objective Genetic Algorithm Approach for Silicon Photonics Design
by Hany Mahrous, Mostafa Fedawy, Mira Abboud, Ahmed Shaker, W. Fikry and Michael Gad
Photonics 2024, 11(1), 80; https://doi.org/10.3390/photonics11010080 - 16 Jan 2024
Cited by 8 | Viewed by 2299
Abstract
A multi-objective genetic algorithm approach is formulated to optimize the design of silicon-photonics complex circuits with contradicting performance metrics and no closed-form expression for the circuit performance. A case study is the interleaver/deinterleaver circuit which mixes/separates optical signals into/from different physical channels while [...] Read more.
A multi-objective genetic algorithm approach is formulated to optimize the design of silicon-photonics complex circuits with contradicting performance metrics and no closed-form expression for the circuit performance. A case study is the interleaver/deinterleaver circuit which mixes/separates optical signals into/from different physical channels while preserving the wavelength-division-multiplexing specifications. These specifications are given as channel spacing of 50 GHz, channel 3-dB bandwidth of at least 20 GHz, channel free spectral range of 100 GHz, crosstalk of −23 dB or less, and signal dispersion less than 30 ps/nm. The essence of the proposed approach lies in the formulation of the fitness functions and the selection criteria to optimize the values of the three coupling coefficients, which govern the circuit performance, in order to accommodate the contradicting performance metrics of the circuit. The proposed approach achieves the optimal design in an incomparably short period of time when contrasted with the previous tedious design method based on employing Z-transform and visual inspection of the transmission poles and zeros. Full article
(This article belongs to the Special Issue Emerging Topics in Structured Light)
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20 pages, 315 KiB  
Article
Application of Fixed Point Result in Complex Valued Extended b-Metric Space
by Amnah Essa Shammaky and Jamshaid Ahmad
Mathematics 2023, 11(24), 4875; https://doi.org/10.3390/math11244875 - 5 Dec 2023
Cited by 1 | Viewed by 940
Abstract
The aim of the present research work is to investigate the solution of Urysohn integral equation by common fixed point result in the setting of complex valued b-metric space. To obtain the objective, we used a generalized rational contraction involving control functions [...] Read more.
The aim of the present research work is to investigate the solution of Urysohn integral equation by common fixed point result in the setting of complex valued b-metric space. To obtain the objective, we used a generalized rational contraction involving control functions and a pair of self-mappings. In this way, we generalize some well-known results of literature. Some non-trivial examples are also flourished to demonstrate the innovation of our principal result. Full article
(This article belongs to the Special Issue New Advances in Mathematical Analysis and Functional Analysis)
18 pages, 325 KiB  
Article
Almost Ćirić Type Contractions and Their Applications in Complex Valued b-Metric Spaces
by Muhammad Sarwar, Syed Khayyam Shah, Zoran D. Mitrović, Aiman Mukheimer and Nabil Mlaiki
Axioms 2023, 12(8), 794; https://doi.org/10.3390/axioms12080794 - 16 Aug 2023
Cited by 3 | Viewed by 1411
Abstract
In this article, we present the use of a unique and common fixed point for a pair of mappings that satisfy certain rational-type inequalities in complex-valued b-metric spaces. We also provide applications related to authenticity concerns in integral equations. Our results combine well-known [...] Read more.
In this article, we present the use of a unique and common fixed point for a pair of mappings that satisfy certain rational-type inequalities in complex-valued b-metric spaces. We also provide applications related to authenticity concerns in integral equations. Our results combine well-known contractions, such as the Ćirić contraction and almost contractions. Full article
(This article belongs to the Special Issue Fixed Point Theory and Its Related Topics IV)
11 pages, 262 KiB  
Article
Multivalued Common Fixed Points Theorem in Complex b-Metric Spaces
by Mohamed Saadi and Taieb Hamaizia
Mathematics 2023, 11(14), 3177; https://doi.org/10.3390/math11143177 - 20 Jul 2023
Cited by 1 | Viewed by 1334
Abstract
In this paper, we establish a result for the existence of common fixed points for multi-valued mappings, satisfying some contractions for complex-valued b-metric spaces. Finally, we present an example to illustrate and support our results. Full article
20 pages, 318 KiB  
Article
Solving Integral Equations via Fixed Point Results Involving Rational-Type Inequalities
by Syed Shah Khayyam, Muhammad Sarwar, Asad Khan, Nabil Mlaiki and Fatima M. Azmi
Axioms 2023, 12(7), 685; https://doi.org/10.3390/axioms12070685 - 12 Jul 2023
Cited by 5 | Viewed by 1831
Abstract
In this study, we establish unique and common fixed point results in the context of a complete complex-valued b-metric space using rational-type inequalities. The presented work generalizes some well-known results from the existing literature. Furthermore, to ensure the validity of the findings, we [...] Read more.
In this study, we establish unique and common fixed point results in the context of a complete complex-valued b-metric space using rational-type inequalities. The presented work generalizes some well-known results from the existing literature. Furthermore, to ensure the validity of the findings, we have included some examples and a section on the existence of solutions for the systems of Volterra–Hammerstein integral equations and Urysohn integral equations, respectively. Full article
(This article belongs to the Special Issue Fixed Point Theory and Its Related Topics IV)
17 pages, 336 KiB  
Article
Fractal Curves on Banach Algebras
by María A. Navascués
Fractal Fract. 2022, 6(12), 722; https://doi.org/10.3390/fractalfract6120722 - 6 Dec 2022
Cited by 8 | Viewed by 1674
Abstract
Most of the fractal functions studied so far run through numerical values. Usually they are supported on sets of real numbers or in a complex field. This paper is devoted to the construction of fractal curves with values in abstract settings such as [...] Read more.
Most of the fractal functions studied so far run through numerical values. Usually they are supported on sets of real numbers or in a complex field. This paper is devoted to the construction of fractal curves with values in abstract settings such as Banach spaces and algebras, with minimal conditions and structures, transcending in this way the numerical underlying scenario. This is performed via fixed point of an operator defined on a b-metric space of Banach-valued functions with domain on a real interval. The sets of images may provide uniparametric fractal collections of measures, operators or matrices, for instance. The defining operator is linked to a collection of maps (or iterated function system, and the conditions on these mappings determine the properties of the fractal function. In particular, it is possible to define continuous curves and fractal functions belonging to Bochner spaces of Banach-valued integrable functions. As residual result, we prove the existence of fractal functions coming from non-contractive operators as well. We provide new constructions of bases for Banach-valued maps, with a particular mention of spanning systems of functions valued on C*-algebras. Full article
(This article belongs to the Section General Mathematics, Analysis)
33 pages, 4253 KiB  
Article
Application of DNA Coding, the Lorenz Differential Equations and a Variation of the Logistic Map in a Multi-Stage Cryptosystem
by Mohamed Gabr, Hana Younis, Marwa Ibrahim, Sara Alajmy, Ijaz Khalid, Eman Azab, Rimon Elias and Wassim Alexan
Symmetry 2022, 14(12), 2559; https://doi.org/10.3390/sym14122559 - 4 Dec 2022
Cited by 50 | Viewed by 3678
Abstract
The need for information security has become urgent due to the constantly changing nature of the Internet and wireless communications, as well as the daily generation of enormous volumes of multimedia. In this paper, a 3-stage image cryptosystem is developed and proposed. A [...] Read more.
The need for information security has become urgent due to the constantly changing nature of the Internet and wireless communications, as well as the daily generation of enormous volumes of multimedia. In this paper, a 3-stage image cryptosystem is developed and proposed. A tan variation of the logistic map is utilized to carry out deoxyribonucleic acid (DNA) encoding in the first stage. For the second encryption stage, the numerical solution of the Lorenz differential equations and a linear descent algorithm are jointly employed to build a robust S-box. The logistic map in its original form is utilized in the third stage. Diffusion is guaranteed through the first and third encryption stages, while confusion is guaranteed through the application of the S-box in the second encryption stage. Carrying out both confusion- and diffusion-inducing stages results in encrypted images that are completely asymmetric to their original (plain) counterparts. An extensive numerical analysis is carried out and discussed, showcasing the robustness and efficacy of the proposed algorithm in terms of resistance to visual, statistical, entropy, differential, known plaint text and brute-force attacks. Average values for the computed metrics are: Information entropy of 7.99, MSE of 9704, PSNR of 8.3 dB, MAE of 80.8, NPCR of 99.6 and UACI of 33. The proposed algorithm is shown to exhibit low computational complexity, encrypting images at an average rate of 1.015 Mbps. Moreover, it possesses a large key space of 2372, and is demonstratd to successfully pass all the tests of the NIST SP 800 suite. In order to demonstrate the superior performance of the proposed algorithm, a comparison with competing image encryption schemes from the literature is also provided. Full article
(This article belongs to the Special Issue Symmetry and Asymmetry in Cryptography)
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38 pages, 2357 KiB  
Article
Mind Your Outcomes: The ΔQSD Paradigm for Quality-Centric Systems Development and Its Application to a Blockchain Case Study
by Seyed Hossein Haeri, Peter Thompson, Neil Davies, Peter Van Roy, Kevin Hammond and James Chapman
Computers 2022, 11(3), 45; https://doi.org/10.3390/computers11030045 - 17 Mar 2022
Cited by 4 | Viewed by 7027
Abstract
This paper directly addresses a long-standing issue that affects the development of many complex distributed software systems: how to establish quickly, cheaply, and reliably whether they can deliver their intended performance before expending significant time, effort, and money on detailed design and implementation. [...] Read more.
This paper directly addresses a long-standing issue that affects the development of many complex distributed software systems: how to establish quickly, cheaply, and reliably whether they can deliver their intended performance before expending significant time, effort, and money on detailed design and implementation. We describe ΔQSD, a novel metrics-based and quality-centric paradigm that uses formalised outcome diagrams to explore the performance consequences of design decisions, as a performance blueprint of the system. The distinctive feature of outcome diagrams is that they capture the essential observational properties of the system, independent of the details of system structure and behaviour. The ΔQSD paradigm derives bounds on performance expressed as probability distributions encompassing all possible executions of the system. The ΔQSD paradigm is both effective and generic: it allows values from various sources to be combined in a rigorous way so that approximate results can be obtained quickly and subsequently refined. ΔQSD has been successfully used by a small team in Predictable Network Solutions for consultancy on large-scale applications in a number of industries, including telecommunications, avionics, and space and defence, resulting in cumulative savings worth billions of US dollars. The paper outlines the ΔQSD paradigm, describes its formal underpinnings, and illustrates its use via a topical real-world example taken from the blockchain/cryptocurrency domain. ΔQSD has supported the development of an industry-leading proof-of-stake blockchain implementation that reliably and consistently delivers blocks of up to 80 kB every 20 s on average across a globally distributed network of collaborating block-producing nodes operating on the public internet. Full article
(This article belongs to the Special Issue Blockchain-Based Systems)
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18 pages, 313 KiB  
Article
Common Fixed Points Technique for Existence of a Solution of Urysohn Type Integral Equations System in Complex Valued b-Metric Spaces
by Muhammad Suhail Aslam, Monica Felicia Bota, Mohammad S. R. Chowdhury, Liliana Guran and Naeem Saleem
Mathematics 2021, 9(4), 400; https://doi.org/10.3390/math9040400 - 18 Feb 2021
Cited by 16 | Viewed by 2626
Abstract
In this paper we give some common fixed point theorems for Ćirić type operators in complex valued b-metric spaces. Also, some corollaries under this contraction condition are obtained. Our results extend and generalize the results of Hammad et al. In the second [...] Read more.
In this paper we give some common fixed point theorems for Ćirić type operators in complex valued b-metric spaces. Also, some corollaries under this contraction condition are obtained. Our results extend and generalize the results of Hammad et al. In the second part of the paper, in order to strengthen our main results, an illustrative example and some applications are given. Full article
(This article belongs to the Special Issue Dynamical Systems and Optimal Control)
24 pages, 4803 KiB  
Article
Adaptive Residual Weighted K-Nearest Neighbor Fingerprint Positioning Algorithm Based on Visible Light Communication
by Shiwu Xu, Chih-Cheng Chen, Yi Wu, Xufang Wang and Fen Wei
Sensors 2020, 20(16), 4432; https://doi.org/10.3390/s20164432 - 8 Aug 2020
Cited by 27 | Viewed by 3411
Abstract
The weighted K-nearest neighbor (WKNN) algorithm is a commonly used fingerprint positioning, the difficulty of which lies in how to optimize the value of K to obtain the minimum positioning error. In this paper, we propose an adaptive residual weighted K-nearest [...] Read more.
The weighted K-nearest neighbor (WKNN) algorithm is a commonly used fingerprint positioning, the difficulty of which lies in how to optimize the value of K to obtain the minimum positioning error. In this paper, we propose an adaptive residual weighted K-nearest neighbor (ARWKNN) fingerprint positioning algorithm based on visible light communication. Firstly, the target matches the fingerprints according to the received signal strength indication (RSSI) vector. Secondly, K is a dynamic value according to the matched RSSI residual. Simulation results show the ARWKNN algorithm presents a reduced average positioning error when compared with random forest (81.82%), extreme learning machine (83.93%), artificial neural network (86.06%), grid-independent least square (60.15%), self-adaptive WKNN (43.84%), WKNN (47.81%), and KNN (73.36%). These results were obtained when the signal-to-noise ratio was set to 20 dB, and Manhattan distance was used in a two-dimensional (2-D) space. The ARWKNN algorithm based on Clark distance and minimum maximum distance metrics produces the minimum average positioning error in 2-D and 3-D, respectively. Compared with self-adaptive WKNN (SAWKNN), WKNN and KNN algorithms, the ARWKNN algorithm achieves a significant reduction in the average positioning error while maintaining similar algorithm complexity. Full article
(This article belongs to the Special Issue Sensors and Systems for Indoor Positioning)
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12 pages, 249 KiB  
Article
Do Fractals Confirm the General Theory of Relativity?
by Irina Rozgacheva
Symmetry 2019, 11(6), 740; https://doi.org/10.3390/sym11060740 - 1 Jun 2019
Cited by 1 | Viewed by 2820
Abstract
The relatively high abundance of fractal properties of complex systems on Earth and in space is considered an argument in support of the general relativity of the geometric theory of gravity. The fractality may be called the fractal symmetry of physical interactions providing [...] Read more.
The relatively high abundance of fractal properties of complex systems on Earth and in space is considered an argument in support of the general relativity of the geometric theory of gravity. The fractality may be called the fractal symmetry of physical interactions providing self-similarities of complex systems. Fractal symmetry is discrete. A class of geometric solutions of the general relativity equations for a complex scalar field is offered. This class allows analogy to spatial fractals in large-scale structures of the universe due to its invariance with respect to the discrete scale transformation of the interval d s q d s ˜ . The method of constructing such solutions is described. As an application, the treatment of spatial variations of the Hubble constant H 0 H S T (Riess et al., 2016) is considered. It is noted that the values H 0 H S T form an almost fractal set. It has been shown that: a) the variation H 0 H S T may be connected with the local gravitational perturbations of the space-time metrics in the vicinity of the galaxies containing Cepheids and supernovae selected for measurements; b) the value of the variation H 0 H S T can be a consequence of variations in the space-time metric on the outskirts of the local supercluster, and their self-similarity indicates the fractal distribution of matter in this region. Full article
(This article belongs to the Special Issue Symmetries in the Universe)
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