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1.
Sci Rep ; 14(1): 11907, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789487

RESUMO

This research focuses on bifurcation analysis and new waveforms for the first fractional 3D Wazwaz-Benjamin-Bona-Mahony (WBBM) structure, which arises in shallow water waves. The linear stability technique is also employed to assess the stability of the mentioned model. The suggested equation's dynamical system is obtained by applying the Galilean transformation to achieve our goal. Subsequently, bifurcation, chaos, and sensitivity analysis of the mentioned model are conducted by applying the principles of the planar dynamical system. We obtain periodic, quasi-periodic, and chaotic behaviors of the mentioned model. Furthermore, we introduce and delve into diverse solitary wave solutions, encompassing bright soliton, dark soliton, kink wave, periodic waves, and anti-kink waves. These solutions are visually presented through simulations, highlighting their distinct characteristics and existence. The results highlight the effectiveness, brevity, and efficiency of the employed integration methods. They also suggest their applicability to delving into more intricate nonlinear models emerging in modern science and engineering scenarios. The novelty of this research lies in its detailed analysis of the governing model, which provides insights into its complex dynamics and varied wave structures. This study also advances the understanding of nonlinear wave properties in shallow water by combining bifurcation analysis, chaotic behavior, waveform characteristics, and stability assessments.

2.
PLoS One ; 19(4): e0300321, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38669251

RESUMO

This work explores diverse novel soliton solutions of two fractional nonlinear models, namely the truncated time M-fractional Chafee-Infante (tM-fCI) and truncated time M-fractional Landau-Ginzburg-Higgs (tM-fLGH) models. The several soliton waves of time M-fractional Chafee-Infante model describe the stability of waves in a dispersive fashion, homogeneous medium and gas diffusion, and the solitary waves of time M-fractional Landau-Ginzburg-Higgs model are used to characterize the drift cyclotron movement for coherent ion-cyclotrons in a geometrically chaotic plasma. A confirmed unified technique exploits soliton solutions of considered fractional models. Under the conditions of the constraint, fruitful solutions are gained and verified with the use of the symbolic software Maple 18. Keeping special values of the constraint, this inquisition achieved kink shape, the collision of kink type and lump wave, the collision of lump and bell type, periodic lump wave, bell shape, some periodic soliton waves for time M-fractional Chafee-Infante and periodic lump, and some diverse periodic and solitary waves for time M-fractional Landau-Ginzburg-Higgs model successfully. The required solutions in this work have many constructive descriptions, and corporal behaviors have been incorporated through some abundant 3D figures with density plots. We compare the m-fractional derivative with the beta fractional derivative and the classical form of these models in two-dimensional plots. Comparisons with others' results are given likewise.


Assuntos
Dinâmica não Linear , Modelos Teóricos , Algoritmos
3.
PLoS One ; 18(9): e0291071, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37695783

RESUMO

In this investigation, we apply the improved Kudryashov, the novel Kudryashov, and the unified methods to demonstrate new wave behaviors of the Fokas-Lenells nonlinear waveform arising in birefringent fibers. Through the application of these techniques, we obtain numerous previously unreported novel dynamic optical soliton solutions in mixed hyperbolic, trigonometric, and rational forms of the governing model. These solutions encompass periodic waves with W-shaped profiles, gradually increasing amplitudes, rapidly increasing amplitudes, double-periodic waves, and breather waves with symmetrical or asymmetrical amplitudes. Singular solitons with single and multiple breather waves are also derived. Based on these findings, we can say that our implemented methods are more reliable and useful when retrieving optical soliton results for complicated nonlinear systems. Various potential features of the derived solutions are presented graphically.

4.
PLoS One ; 18(7): e0283594, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37498833

RESUMO

The Zoomeron equation is used in various categories of soliton with unique characteristics that arise in different physical phenomena, such as fluid dynamics, laser physics, and nonlinear optics. To achieve soliton solutions for the Zoomeron nonlinear structure, we apply the unified, the Kudryashov, and the improved Kudryashov techniques. We find periodic, breather, kink, anti-kink, and dark-bell soliton solutions from the derived optical soliton solutions. Bright, dark, and bright-dark breather waves are also established. Finally, some dynamic properties of the acquired findings are displayed in 3D, density, and 2D views.


Assuntos
Dinâmica não Linear , Óptica e Fotônica , Fenômenos Físicos , Luz , Hidrodinâmica
5.
Heliyon ; 9(6): e16570, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37332926

RESUMO

This article explores on a stochastic couple models of ion sound as well as Langmuir surges propagation involving multiplicative noises. We concentrate on the analytical stochastic solutions including the travelling and solitary waves by using the planner dynamical systematic approach. To apply the method, First effort is to convert the system of equations into the ordinary differential form and present it in form of a dynamic structure. Next analyze the nature of the critical points of the system and obtain the phase portraits on various conditions of the corresponding parameters. The analytic solutions of the system in an account of distinct energy states for each phase orbit are performed. We also show how the results are highly effective and interesting to realize their exciting physical as well as the geometrical phenomena based on the demonstration of the stochastic system involving ion sound as well as Langmuir surges. Descriptions of effectiveness of the multiplicative noise on the obtained solutions of the model, and its corresponding figures are demonstrated numerically.

6.
Heliyon ; 8(12): e11996, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36506367

RESUMO

This study presents a modification form of modified simple equation method, namely new modified simple equation method. Multiple waves and interaction of soliton solutions of the Phi-4 and Klein-Gordon models are investigated via the scheme. Consequently, we derive various novels and more general interaction, and multiple wave solutions in term of exponential, hyperbolic, and trigonometric, rational function solutions combining with some free parameters. Taking special values of the free parameters, interaction of two dark bells, interaction of two bright bells, two kinks, two periodic waves, kink and soliton, kink-rogue wave solutions are obtained which is the key significance of this method. Properties of the achieved solutions have many useful descriptions of physical behavior, correlated to the solutions are attained in this work through plentiful 3D figures, density plot and 2D contour plots. The results derived may increase the prospect of performing significant experimentations and carry out probable applications.

7.
BMJ Open ; 12(12): e065674, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36581408

RESUMO

OBJECTIVES: The prime objectives of the study were to measure the prevalence of facility delivery, assess socioeconomic inequalities and determine potential associated factors in the use of facility delivery in Bangladesh.DesignCross-sectional. SETTING: The study involved investigation of nationally representative secondary data from the Bangladesh Demographic and Health Survey between 2007 and 2017-2018. PARTICIPANTS: The participants of this study were 30 940 (weighted) Bangladeshi women between the ages of 15 and 49. METHODS: Decomposition analysis and multivariable logistic regression were both used to analyse data to achieve the study objectives. RESULTS: The prevalence of using facility delivery in Bangladesh has increased from 14.48% in 2007 to 49.26% in 2017-2018. The concentration index for facility delivery utilisation was 0.308 with respect to household wealth status (p<0.001), indicating that use of facility delivery was more concentrated among the rich group of people. Decomposition analysis also indicated that wealth quintiles (18.31%), mothers' education (8.78%), place of residence (7.75%), birth order (5.56%), partners' education (4.30%) and antenatal care (ANC) seeking (8.51%) were the major contributors to the prorich socioeconomic inequalities in the use of facility delivery. This study found that women from urban areas, were overweight, had any level of education, from wealthier families, had ANC, and whose partners had any level of education and involved in business were more likely to have facility births compared with their respective counterparts. CONCLUSIONS: This study found a prorich inequality in the use of facility delivery in Bangladesh. The socioeconomic disparities in facility delivery must be addressed if facility delivery usage is to increase in Bangladesh.


Assuntos
Parto , Cuidado Pré-Natal , Gravidez , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Bangladesh/epidemiologia , Fatores Socioeconômicos , Escolaridade , Prevalência
8.
Heliyon ; 8(10): e10924, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36267371

RESUMO

We present the unified method and use it to integrate the ion sound and Langmuir waves (ISLW) model to retrieve optical soliton solutions. Some new dynamical optical solitons involving the combo of rational, trigonometric, and hyperbolic function solutions are added in this study. The derived optical soliton solutions display various properties such as beat pattern and oscillation with increasing, decreasing, and simultaneously increasing and decreasing amplitudes. Moreover, kink, dark bell, singular kink, single breather, multiple breathers, dark-, bright-, and dark bright periodic waves are founded. Finally, some dynamical characteristics of the acquired solutions are depicted.

9.
Reprod Health ; 19(1): 17, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35062956

RESUMO

BACKGROUND: We aimed to determine the factors that increase the risk of HRFB in Bangladeshi women of reproductive age 15-49 years. METHODS: The study utilised the latest Bangladesh Demographic and Health Survey (BDHS) 2017-18 dataset. The Pearson's chi-square test was performed to determine the relationships between the outcome and the independent variables, while multivariate logistic regression analysis was used to identify the potential determinants associated with HRFB. RESULTS: Overall 67.7% women had HRFB among them 45.6% were at single risk and 22.1% were at multiple high-risks. Women's age (35-49 years: AOR = 6.42 95% CI 3.95-10.42), who were Muslims(AOR = 5.52, 95% CI 2.25-13.52), having normal childbirth (AOR = 1.47, 95% CI 1.22-1.69), having unwanted pregnancy (AOR = 10.79, 95% CI 5.67-18.64) and not using any contraceptive methods  (AOR = 1.37, 95% CI 1.24-1.81) were significantly associated with increasing risk of having HRFB. Alternatively, women and their partners' higher education were associated with reducing HRFB. CONCLUSION: A significant proportion of Bangladeshi women had high-risk fertility behaviour which is quite alarming. Therefore, the public health policy makers in Bangladesh should emphasis on this issue and design appropriate interventions to reduce the maternal HRFB.


High rates of maternal high-risk fertility behaviour (HRFB) have a variety of unfavourable repercussions for both the mother and the child. However, because there have been few studies on this topic to date, we set out to identify the determinants that enhance the risk of HRFB in Bangladeshi women between the ages of 15 and 49. Using latest demographic and health survey (BDHS) data we have found that 67.7% of women had HRFB, with 45.6% having a single high-risk factor and 22.1% having multiple high-risk factors. This high prevalence rate demonstrates that HRFB are all too common in Bangladesh, potentially endangering the health of the country's women. We found that women practicing Islam as core religion, age above 35 years, having normal childbirth, having above 3 children, having unwanted pregnancies and not using birth control methods were at increased risk of having HRFB. As a result of the study's findings, interventions are urgently needed to prevent high-risk fertility behaviour among Bangladeshi women aged 15 to 49 years.


Assuntos
Fertilidade , Reprodução , Adolescente , Adulto , Bangladesh/epidemiologia , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Gravidez , Fatores Socioeconômicos , Adulto Jovem
10.
Heliyon ; 6(4): e03701, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32322710

RESUMO

A bilinear form of the (2+1)-dimensional nonlinear Calogero-Bogoyavlenskii-Schiff (CBS) model is derived using a transformation of dependent variable, which contain a controlling parameter. This parameter can control the direction, wave height and angle of the traveling wave. Based on the Hirota bilinear form and ansatz functions, we build many types of novel structures and manifold periodic-soliton solutions to the CBS model. In particular, we obtain entirely exciting periodic-soliton, cross-kinky-lump wave, double kinky-lump wave, periodic cross-kinky-lump wave, periodic two-solitary wave solutions as well as breather style of two-solitary wave solutions. We present their propagation features via changing the existence parametric values in graphically. In addition, we estimate a condition that the waves are propagated obliquely for η ≠ 0 , and orthogonally for η = 0 .

11.
Heliyon ; 5(10): e02548, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31667398

RESUMO

In this work, we consider a (2 + 1)-dimensional asymmetric Nizhnik-Novikov-Veselov (ANNV) equation, which has applications in processes of interaction of exponentially localized structures. Based on the bilinear formalism and with the aid of symbolic computation, we determine multi-solitons, breather solutions, lump soliton, lump-kink waves and multi lumps using various ansatze's function. We notice that multi-lumps in the form of breathers visualize as a straight line. To realize dynamics, we commit diverse graphical analysis on the presented solutions. Obtained solutions are reliable in the mathematical physics and engineering.

12.
Heliyon ; 4(8): e00756, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30186980

RESUMO

Two nonlinear evolution equations, namely the Kadomtsev-Petviashvili (KP) equation which describes the dynamics of soliton and nonlinear wave in the field of fluid dynamics, plasma physics and the Oskolkov equation which describes the dynamics of an incompressible visco-elastic Kelvin-Voigt fluid are investigated. We deliberate exact traveling wave solutions, specially kink wave, cusp wave, periodic breather waves and periodic wave solutions of the models applying the modified simple equation method. The solutions can be expressed explicitly. The dynamics of obtained wave solutions are analyzed and illustrated in figures by selecting appropriate parameters. The modified simple equation method is reliable treatment for searching essential nonlinear waves that enrich variety of dynamic models arises in engineering fields.

13.
Springerplus ; 3: 43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24570845

RESUMO

ABSTRACT: Exact solutions of nonlinear evolution equations (NLEEs) play a vital role to reveal the internal mechanism of complex physical phenomena. In this work, the exact traveling wave solutions of the Boussinesq equation is studied by using the new generalized (G'/G)-expansion method. Abundant traveling wave solutions with arbitrary parameters are successfully obtained by this method and the wave solutions are expressed in terms of the hyperbolic, trigonometric, and rational functions. It is shown that the new approach of generalized (G'/G)-expansion method is a powerful and concise mathematical tool for solving nonlinear partial differential equations in mathematical physics and engineering. PACS: 05.45.Yv, 02.30.Jr, 02.30.Ik.

14.
Springerplus ; 3: 122, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25674431

RESUMO

In this article, a new extended (G'/G) -expansion method has been proposed for constructing more general exact traveling wave solutions of nonlinear evolution equations with the aid of symbolic computation. In order to illustrate the validity and effectiveness of the method, we pick the (3 + 1)-dimensional potential-YTSF equation. As a result, abundant new and more general exact solutions have been achieved of this equation. It has been shown that the proposed method provides a powerful mathematical tool for solving nonlinear wave equations in applied mathematics, engineering and mathematical physics.

15.
Springerplus ; 3: 692, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26034687

RESUMO

In this paper, we have described two dreadfully important methods to solve nonlinear partial differential equations which are known as exp-function and the exp(-ϕ(ξ)) -expansion method. Recently, there are several methods to use for finding analytical solutions of the nonlinear partial differential equations. The methods are diverse and useful for solving the nonlinear evolution equations. With the help of these methods, we are investigated the exact travelling wave solutions of the Vakhnenko- Parkes equation. The obtaining soliton solutions of this equation are described many physical phenomena for weakly nonlinear surface and internal waves in a rotating ocean. Further, three-dimensional plots of the solutions such as solitons, singular solitons, bell type solitary wave i.e. non-topological solitons solutions and periodic solutions are also given to visualize the dynamics of the equation.

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