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Article ; Online: Silhouette Analysis for Performance Evaluation in Machine Learning with Applications to Clustering

Meshal Shutaywi / Nezamoddin N. Kachouie

Entropy, Vol 23, Iss 759, p

2021 Volume 759

Abstract: Grouping the objects based on their similarities is an important common task in machine learning applications. Many clustering methods have been developed, among them k-means based clustering methods have been broadly used and several extensions have ... ...

Abstract	Grouping the objects based on their similarities is an important common task in machine learning applications. Many clustering methods have been developed, among them k-means based clustering methods have been broadly used and several extensions have been developed to improve the original k-means clustering method such as k-means ++ and kernel k-means. K-means is a linear clustering method; that is, it divides the objects into linearly separable groups, while kernel k-means is a non-linear technique. Kernel k-means projects the elements to a higher dimensional feature space using a kernel function, and then groups them. Different kernel functions may not perform similarly in clustering of a data set and, in turn, choosing the right kernel for an application could be challenging. In our previous work, we introduced a weighted majority voting method for clustering based on normalized mutual information (NMI). NMI is a supervised method where the true labels for a training set are required to calculate NMI. In this study, we extend our previous work of aggregating the clustering results to develop an unsupervised weighting function where a training set is not available. The proposed weighting function here is based on Silhouette index, as an unsupervised criterion. As a result, a training set is not required to calculate Silhouette index. This makes our new method more sensible in terms of clustering concept.
Keywords	k-means ; kernel k-means ; machine learning ; nonlinear clustering ; silhouette index ; weighted clustering ; Science ; Q ; Astrophysics ; QB460-466 ; Physics ; QC1-999
Subject code	006
Language	English
Publishing date	2021-06-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Weighted Mutual Information for Aggregated Kernel Clustering

Nezamoddin N. Kachouie / Meshal Shutaywi

Entropy, Vol 22, Iss 3, p

2020 Volume 351

Abstract: Background: A common task in machine learning is clustering data into different groups based on similarities. Clustering methods can be divided in two groups: linear and nonlinear. A commonly used linear clustering method is K-means. Its extension, ... ...

Abstract	Background: A common task in machine learning is clustering data into different groups based on similarities. Clustering methods can be divided in two groups: linear and nonlinear. A commonly used linear clustering method is K-means. Its extension, kernel K-means, is a non-linear technique that utilizes a kernel function to project the data to a higher dimensional space. The projected data will then be clustered in different groups. Different kernels do not perform similarly when they are applied to different datasets. Methods: A kernel function might be relevant for one application but perform poorly to project data for another application. In turn choosing the right kernel for an arbitrary dataset is a challenging task. To address this challenge, a potential approach is aggregating the clustering results to obtain an impartial clustering result regardless of the selected kernel function. To this end, the main challenge is how to aggregate the clustering results. A potential solution is to combine the clustering results using a weight function. In this work, we introduce Weighted Mutual Information (WMI) for calculating the weights for different clustering methods based on their performance to combine the results. The performance of each method is evaluated using a training set with known labels. Results: We applied the proposed Weighted Mutual Information to four data sets that cannot be linearly separated. We also tested the method in different noise conditions. Conclusions: Our results show that the proposed Weighted Mutual Information method is impartial, does not rely on a single kernel, and performs better than each individual kernel specially in high noise.
Keywords	weighted mutual information ; aggregated clustering ; kernel k-means ; conditional entropy ; Science ; Q ; Astrophysics ; QB460-466 ; Physics ; QC1-999
Subject code	006
Language	English
Publishing date	2020-03-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Improved Knowledge Measures for q-Rung Orthopair Fuzzy Sets

Muhammad Jabir Khan / Poom Kumam / Meshal Shutaywi / Wiyada Kumam

International Journal of Computational Intelligence Systems, Vol 14, Iss

2021 Volume 1

Abstract: The q-rung orthopair fuzzy set (qROFS) defined by Yager is a generalization of Atanassov intuitionistic fuzzy set (IFS) and Pythagorean fuzzy sets (PyFSs). In this paper, we define the knowledge measure for qROFS by using the cosine inverse function. The ...

Abstract	The q-rung orthopair fuzzy set (qROFS) defined by Yager is a generalization of Atanassov intuitionistic fuzzy set (IFS) and Pythagorean fuzzy sets (PyFSs). In this paper, we define the knowledge measure for qROFS by using the cosine inverse function. The information precision and information content are two facets of knowledge measure. Both facets of knowledge measure are considered. The properties of knowledge measure and their graphical explanations are discussed. An application of the knowledge measure in multi-attribute group decision-making (MAGDM) problem under the confidence level approach is given. A numerical example of the selection of renewable energy sources is discussed.
Keywords	Knowledge measure ; q-rung orthopair fuzzy sets ; Entropy ; MAGDM ; Electronic computers. Computer science ; QA75.5-76.95
Language	English
Publishing date	2021-06-01T00:00:00Z
Publisher	Springer
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Fractional Dynamics of HIV with Source Term for the Supply of New CD4 + T-Cells Depending on the Viral Load via Caputo–Fabrizio Derivative

Zahir Shah / Rashid Jan / Poom Kumam / Wejdan Deebani / Meshal Shutaywi

Molecules, Vol 26, Iss 1806, p

2021 Volume 1806

Abstract: Human immunodeficiency virus (HIV) is a life life-threatening and serious infection caused by a virus that attacks ... CD ... 4 ... + ...

Abstract	Human immunodeficiency virus (HIV) is a life life-threatening and serious infection caused by a virus that attacks <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow><mi>CD</mi><mn>4</mn></mrow><mo>+</mo></msup></semantics></math> T-cells, which fight against infections and make a person susceptible to other diseases. It is a global public health problem with no cure; therefore, it is highly important to study and understand the intricate phenomena of HIV. In this article, we focus on the numerical study of the path-tracking damped oscillatory behavior of a model for the HIV infection of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow><mi>CD</mi><mn>4</mn></mrow><mo>+</mo></msup></semantics></math> T-cells. We formulate fractional dynamics of HIV with a source term for the supply of new CD4 + T-cells depending on the viral load via the Caputo–Fabrizio derivative. In the formulation of fractional HIV dynamics, we replaced the constant source term for the supply of new <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow><mi>CD</mi><mn>4</mn></mrow><mo>+</mo></msup></semantics></math> T-cells from the thymus with a variable source term depending on the concentration of the viral load, and introduced a term that describes the incidence of the HIV infection of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow><mi>CD</mi><mn>4</mn></mrow><mo>+</mo></msup></semantics></math> T-cells. We present a novel numerical scheme for fractional view analysis of the proposed model to highlight the solution pathway of HIV. We inspect the periodic and ...
Keywords	human immunodeficiency virus ; fractional dynamics ; Caputo–Fabrizio derivative ; numerical scheme ; solutions pathway ; Organic chemistry ; QD241-441
Subject code	518
Language	English
Publishing date	2021-03-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Second-order slip effect on bio-convectional viscoelastic nanofluid flow through a stretching cylinder with swimming microorganisms and melting phenomenon

Hassan Waqas / Umar Farooq / Zahir Shah / Poom Kumam / Meshal Shutaywi

Scientific Reports, Vol 11, Iss 1, Pp 1-

2021 Volume 16

Abstract: Abstract The uses of nanofluid in cooling technology is growing. The nanofluid is made up of metallic and nonmetallic particles that are distributed in a base fluid. This research provides a summary of fuel cell models, uses, and how they function. ... ...

Abstract	Abstract The uses of nanofluid in cooling technology is growing. The nanofluid is made up of metallic and nonmetallic particles that are distributed in a base fluid. This research provides a summary of fuel cell models, uses, and how they function. Researchers have made significant contributions in the following era due to the importance of bioconvection in nanotechnology and a variety of biological systems. The idea of the recent work is to evaluate the aspects of the Cattaneo–Christov (C–C) heat and mass flux model, the second-order boundary with melting phenomenon on the bioconvective flow of viscoelastic nanofluid across a cylinder. The nature of the activation energy, thermal conductivity is also taken into account. Appropriate similarity transformations are utilized to reframe the PDEs of the modeled system into a system of ODEs. The governing equations for the renovated system of ODEs are treated by a shooting function. Here bvp4c built-in function computational tool MATLAB is used. The two-dimensional flow has ceased application in several areas, such as polymer industry, material synthesis technology, nano-biopolymer computer graphics processing, industry, mechanical engineering, airplane structures, and scientific research, which is much more useful in nanotechnology. The results of emerging important flow-field parameters are investigated with the aid of graphs and numerical results.
Keywords	Medicine ; R ; Science ; Q
Subject code	621
Language	English
Publishing date	2021-05-01T00:00:00Z
Publisher	Nature Portfolio
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Statistical modeling for Ree-Eyring nanofluid flow in a conical gap between porous rotating surfaces with entropy generation and Hall Effect

Muhammad Rooman / Anum Shafiq / Zahir Shah / Narcisa Vrinceanu / Wejdan Deebani / Meshal Shutaywi

Scientific Reports, Vol 12, Iss 1, Pp 1-

2022 Volume 22

Abstract: Abstract The attention of the current study is on the flow of a non-Newtonian incompressible Cu-Water nanofluid flow. The water is assumed as base fluid, while copper is used as nanoparticles. The Ree-Eyring prototype describes the performance of non- ... ...

Abstract	Abstract The attention of the current study is on the flow of a non-Newtonian incompressible Cu-Water nanofluid flow. The water is assumed as base fluid, while copper is used as nanoparticles. The Ree-Eyring prototype describes the performance of non-Newtonian nanofluids. There is a conical gap that nanofluid flow fills among the plane disc and the cone's stationary/rotational porous faces. Additionally taken into account are heat, mass transfer, and entropy production. The given mathematical model is unique due to the effects of a vertically applied Hall Effect, Ohmic dissipation, viscous dissipation, and chemical processes. The Ree-Eyring fluid constitutive equations, as well as the cylindrical coordinates, have been interpreted. The model equations for motion, heat, and concentration can be changed in the collection of non-linear ODEs by employing the applicable similarity transform. This method allocates a couple of nonlinear ODEs relating to velocity, temperature, and concentration distributions. The shooting scheme (bvp4c technique) is used to solve these equations numerically. Statistical analysis like probable error, correlation, and regression are exploited. The probable error is estimated to compute the consistency of the calculated correlation features. The theoretical data is analyzed in both graphical and tabular forms. The modeled parameters like, magnetic number, porosity parameter, Eckert number, chemical reaction parameter, Brownian motion parameter, thermophoretic parameter, Schmidt number, Hall recent parameter, radiation parameter, and volume fraction are discussed in details graphically and theoretically. The outcomes indicate that the velocity components are greater for greater values of nanoparticle volume fraction and Weissenberg number, whereas for enormous values of magnetic and porosity parameters, the velocity components fall.
Keywords	Medicine ; R ; Science ; Q
Subject code	532
Language	English
Publishing date	2022-12-01T00:00:00Z
Publisher	Nature Portfolio
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Modeling and Analysis of Breast Cancer with Adverse Reactions of Chemotherapy Treatment through Fractional Derivative

Tao-Qian Tang / Zahir Shah / Ebenezer Bonyah / Rashid Jan / Meshal Shutaywi / Nasser Alreshidi

Computational and Mathematical Methods in Medicine, Vol

2022 Volume 2022

Abstract: The abnormal growth of cells in the breast is called malignancy or breast cancer; it is a life-threatening and dangerous cancer in women around the world. In the treatment of cancer, the doctors apply different techniques to stop cancer cell development, ...

Abstract	The abnormal growth of cells in the breast is called malignancy or breast cancer; it is a life-threatening and dangerous cancer in women around the world. In the treatment of cancer, the doctors apply different techniques to stop cancer cell development, remove cancer cells through surgery, or kill cancer cells. In chemotherapy treatment, powerful drugs are used to kill abnormal cells; however, it has adverse reactions on the patient heart which is called cardiotoxicity. In this paper, we formulate the dynamics of cancer in the breast with adverse reactions of chemotherapy treatment on the heart of a patient in the fractional framework to visualize its dynamical behaviour. We listed the fundamental results of the fractional calculus for the analysis of our model. The model is then analyzed for the basic properties, and the existence and uniqueness of the proposed breast cancer system are investigated through fixed point theory. Furthermore, the Adams-Bashforth numerical technique is presented for the solution of fractional-order system to illustrate the time series of breast cancer model. The dynamical behaviour of different stages of breast cancer is then highlighted numerically to show the effect of fractional-order ϑ and to visualize the role of input parameter on the dynamics of breast cancer.
Keywords	Computer applications to medicine. Medical informatics ; R858-859.7
Subject code	616
Language	English
Publishing date	2022-01-01T00:00:00Z
Publisher	Hindawi Limited
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Effect of Thermal Radiation on Three-Dimensional Magnetized Rotating Flow of a Hybrid Nanofluid

Adnan Asghar / Liaquat Ali Lund / Zahir Shah / Narcisa Vrinceanu / Wejdan Deebani / Meshal Shutaywi

Nanomaterials, Vol 12, Iss 1566, p

2022 Volume 1566

Abstract: The effect of thermal radiation on the three-dimensional magnetized rotating flow of a hybrid nanofluid has been numerically investigated. Enhancing heat transmission is a contemporary engineering challenge in a range of sectors, including heat ... ...

Abstract	The effect of thermal radiation on the three-dimensional magnetized rotating flow of a hybrid nanofluid has been numerically investigated. Enhancing heat transmission is a contemporary engineering challenge in a range of sectors, including heat exchangers, electronics, chemical and biological reactors, and medical detectors. The main goal of the current study is to investigate the effect of magnetic parameter, solid volume fraction of copper, Eckert number, and radiation parameter on velocity and temperature distributions, and the consequence of solid volume fraction on declined skin friction and heat transfer against suction and a stretching/shrinking surface. A hybrid nanofluid is a contemporary type of nanofluid that is used to increase heat transfer performance. A linear similarity variable is–applied to convert the governing partial differential equations (PDEs) into corresponding ordinary differential equations (ODEs). Using the three-stage Labatto III-A method included in the MATLAB software’s bvp4c solver, the ODE system is solved numerically. In certain ranges of involved parameters, two solutions are received. The temperature profile <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>θ</mi><mfenced><mi>η</mi></mfenced></mrow></semantics></math> upsurges in both solutions with growing values of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>E</mi><mi>C</mi></mrow></semantics></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>R</mi><mi>d</mi></mrow></semantics></math> . Moreover, the conclusion is that solution duality exists when the suction parameter <math xmlns="http://www.w3.org/1998/Math/MathML" ...<br />
Keywords	thermal radiation ; hybrid nanofluid ; Joule heating ; radiation ; dual solution ; Chemistry ; QD1-999
Subject code	511
Language	English
Publishing date	2022-05-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Magnetized mixed convection hybrid nanofluid with effect of heat generation/absorption and velocity slip condition

Adnan Asghar / Abdul Fattah Chandio / Zahir Shah / Narcisa Vrinceanu / Wejdan Deebani / Meshal Shutaywi / Liaquat Ali Lund

Heliyon, Vol 9, Iss 2, Pp e13189- (2023)

2023

Abstract: Through a vertically shrinking sheet, a two-dimensional magnetic nanofluid is numerically analyzed for convection, heat generation and absorption, and the slip velocity effect. In this research, Al2O3–Cu/water composite nanofluid is studied, where water ... ...

Abstract	Through a vertically shrinking sheet, a two-dimensional magnetic nanofluid is numerically analyzed for convection, heat generation and absorption, and the slip velocity effect. In this research, Al2O3–Cu/water composite nanofluid is studied, where water is deemed the base liquid and copper (Cu) and alumina (Al2O3) are the solid nanoparticles. Modern composite nanofluids improve heat transfer efficiency. Using the Tiwari-Das model, the current study examines the effects of the solid volume fraction of copper, heat generation/absorption, MHD, mixed convection, and velocity slip parameters on velocity and temperature distributions. Introducing exponential similarity variables converts nonlinear partial differential equations (PDEs) to ordinary differential equations (ODEs). MATLAB bvp4c solver is used to solve ODEs. Results showed dual solutions for suction with 0%–10% copper nanoparticles and 1%–500% heat generation/absorption. As copper (Cu) solid volume percentage increases from 0% to 10%, reduced skin friction f″(0) boosts in the first solution but falls in the second. When Cu is added to both solutions, heat transport −θ′(0) decreases. As heat generation/absorption increases 1%–500%, −θ′(0) decreases in both solutions. In conclusion, solution dichotomy exists when suction parameter S≥Sci in assisting flow case, while no fluid flow is possible when S<Sci.<br />
Keywords	MHD ; Hybrid nanofluid ; Heat generation/absorption ; Exponentially shrinking surface ; Velocity slip condition ; Mixed convection ; Science (General) ; Q1-390 ; Social sciences (General) ; H1-99
Subject code	532
Language	English
Publishing date	2023-02-01T00:00:00Z
Publisher	Elsevier
Document type	Article ; Online
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Article ; Online: A comprehensive study to the assessment of Arrhenius activation energy and binary chemical reaction in swirling flow

Noor Saeed Khan / Zahir Shah / Meshal Shutaywi / Poom Kumam / Phatiphat Thounthong

Scientific Reports, Vol 10, Iss 1, Pp 1-

2020 Volume 21

Abstract: Abstract Nanotechnology research has a huge impact upon biomedicine and at the forefront of this area are micro and nano devices that use active/controlled motion. In this connection, it is focus to investigate steady three dimensional rotating flow with ...

Abstract	Abstract Nanotechnology research has a huge impact upon biomedicine and at the forefront of this area are micro and nano devices that use active/controlled motion. In this connection, it is focus to investigate steady three dimensional rotating flow with heat and mass transfer incorporating gyrotactic microorganisms. Buongiorno’s nanofluid formulation is followed for thermophoresis and Brownian motion, porous space, Arrhenius activation energy and binary chemical reaction with some other effects. An enhanced analytical method is applied to solve the nondimensional equations. The non-dimensional parameters effects on the fields of velocity, temperature, nanoparticles concentration and gyrotactic microorganisms concentration are shown graphically. Velocity decreases while temperature and nanoparticles concentration increase with magnetic field strength. Gyrotatic microorganisms motion becomes slow with rotation parameter. Due to rotation, the present problem can be applied in microbial fuel cells, food processing, microbiology, biotechnology and environmental sciences, electric power generating and turbine systems, computer disk drives, mass spectromentries and jet motors.
Keywords	Medicine ; R ; Science ; Q
Subject code	532
Language	English
Publishing date	2020-05-01T00:00:00Z
Publisher	Nature Publishing Group
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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