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In this paper, perturbed Chen–Lee–Liu equation is considered to describe pulse propagation in optical fibers. Chen–Lee–Liu equation is a derivative form of the nonlinear Schrodinger equation. Two renowned analytical techniques namely, $$\exp (-\varphi (\eta ))$$ -expansion method and the generalized Kudryashov method are applied to analyze this model. The algorithm of these methods is also presented. Different structures of soliton solutions are successfully investigated for perturbed this model. Additionally, constraint conditions on coefficients of perturbation terms are also defined to assure the existence of such solitons. The graphical representation of these solutions is shown to demonstrate the dynamics of pulse propagation governed by Chen–Lee–Liu equation in optical fibers.

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie [grant No. 814078]. Interoperability in smart manufacturing refers to how interconnected cyber-physical components exchange information and interact. This is still an exploratory topic, and despite the increasing number of applications, many challenges remain open. This chapter presents an integrative framework to understand common practices, concepts, and technologies used in trending research to achieve interoperability in production systems. The chapter starts with the question of what interoperability is and provides an alternative answer based on influential works in the field, followed by the presentation of important reference models and their relation to smart manufacturing. It continues by discussing different types of interoperability, data formats, and common ontologies necessary for the integration of heterogeneous systems and the contribution of emerging technologies in achieving interoperability. This chapter ends with a discussion of a recent use case and final remarks. publishersversion published

In this article, we construct the exact solutions of Kudryashov–Sinelshchikov equation (KSE) which is the generalization of KdV and describes the nonlinear waves in mixtures of gas–liquid in the absence of viscosity. We apply the Sardar-subequation method and the new extended hyperbolic function method to construct the exact solutions of KSE. Various novel computational solutions are demonstrated by two distinct types of sketches. These solutions reveal that current techniques are appropriate, fruitful and straightforward.

In the present work, a novel packed bed external loop pneumatically agitated airlift bioreactor with an internal gas distributor (perforated plate) between two rolls of packing in the riser was designed and built. This novel approach combines advantages of packed bed and external loop airlift bioreactors. The main objective of this research work was to characterize the hydrodynamic performance of this novel reactor through a non-intrusive flow visualization technique called electrical resistance tomography (ERT). The tomography images, which were generated using a linear back projection algorithm, were employed to explore the effects of different design parameters and operating conditions. These include the effect of the two packing in the riser and the internal gas distributor (perforated plate) installed between the two packing. Other parameters investigated include the effect of sparger configuration, gas flow rate, and liquid height in the bioreactor on the different hydrodynamic parameters such as gas holdup, mixing time, and liquid circulation velocity. Results showed that the gas holdup and mixing time increased in the presence of the gas distributor, while the riser superficial liquid velocity was decreased. Furthermore, gas holdup and mixing time increased, superficial liquid velocity decreased when decreasing liquid height in the reactor, and when using packing or gas distributor between two packings in the riser. These results can be used to improve mixing characteristics in external loop airlift bioreactors for wider range of applications.

Mould design and development are experience-oriented operations involving complex process planning integration and relatively time-consuming processes. A solution for integrating the process planning with manufacturing operations for mould design and development is presented. In this paper, the developed solution is related to cost and time. The main aim of the study is to optimize the whole process planning scenario and make it feasible and accessible for faster and optimum design to manufacture die and moulds for injection moulding applications. The developed method consists of group technology (GT) coding for part and tool linked to the manufacturing process and its criticalities. An impact factor rating system is established using the weighted average method to associate the manufacturing operations with time and cost combined with the matrix reduction method so as to produce an optimized sequence of operations. The effect of restricting certain criticalities (electric discharge machine usage, quality and complexity) on the GT code is also elaborated in reference to quality and other parameters. The resultant study presents a novel method of establishing an expert system (ES) that combines GT coding, manufacturing operations, weighted average and matrix reduction to optimize the process planning. The rationale behind the research is an effective use of the ES in optimizing process planning applications in digital manufacturing.

In this work, we developed homotopy perturbation double Sumudu transform method (HPDSTM) which is obtained by combining homotopy perturbation method, double Sumudu transform and He’s polynomials. The method is applied to find the solution of linear fractional one and two dimensional dispersive KdV and nonlinear fractional KdV equations to illustrate the reliability of the method. It is observed that the solutions obtained by the method converge rapidly to the exact solutions. This method is very powerful, and professional techniques for solving different kinds of linear and nonlinear fractional order differential equations.

The article studies the dynamics of dark, singular, combined optical solitons and many other periodic solutions to fractional temporal perturbed nonlinear Schrodinger equation in nonlinear optics. The fractional extended Fan sub-equation method is first time used for any fractional temporal nonlinear Schrodinger equation. The solutions are of qualitatively different nature, depending on the five parameters. The constraint conditions, for the existence of the solitons, are also listed. Moreover a couple of other solutions known as combined soliton and combined periodic solution, fall out as a by product in limiting cases.

In this comment, we looked into solutions drawn by authors in the paper [1] and pointed out that many of them are incorrect. We showed that the conditions obtained by the authors [1] did not satisfy the solutions. Therefore, many of the results in [1] are not true.

The authors in [1] obtained exact solutions of the Biswas and Milovic equation with Kerr law, parabolic law, power law and dual power law nonlinearity using exp(− ϕ(e))-expansion method. The present comment concerns some doubtful results obtained and presented by authors in paper [1] .

In this work, we demonstrate the extraction of some optical soliton solutions of the Chen–Lee–Liu equation (CLLE) with applications in optical fibers. A novel method is presented which is called the new extended direct algebraic method (EDAM). This method is based on converting the nonlinear CLLE equation into an ordinary type equation through a wave transformation. We acquire new solutions like dark, bright, combined dark-bright, combined bright-singular and periodic singular soliton solutions by using this effective technique. These acquired soliton solutions are new with some new physical properties. Some graphical representations for these solutions are provided which prove that the new method is effective and can be extended to some similar problems.

In this article, the Resonant nonlinear Schrodinger equation (RNLSE) having anti-cubic nonlinearity is solved, using the generalized Kudryashov method. Nonlinear Schrodinger equation is a comprehensive model that governs wave behavior in optical fiber. We have investigated cubic-quintic RNLSE with the anti-cubic nonlinear terms. Bright, dark, kink, and singular soliton solutions of this equation are successfully achieved. The solutions obtained through the generalized Kudryashov method are in exponential functions form and which are reduced to hyperbolic functions form. The two and three-dimensional graphs of acquired solutions are plotted in order to present the dynamics of these solutions.

In this paper, we applied the extended direct algebraic method (EDAM) to examine the dark, singular, combined dark-bright, combined bright-singular and periodic singular solitons as well as hyperbolic and trigonometric functions solutions of Biswas-Arshed equation (BAE) in birefringent fibers. The outcomes reveal that our technique is very dynamic and straightforward. The determined solutions of this model are new in the literature.

This work scrutinizes optical solitons in birefringent fibers with the advocacy of a novel model, the Biswas–Arshed equation with higher order dispersions in Kerr-law media, where four-wave mixing terms are not included. Two resourceful integration techniques which are auxiliary equation method and Sine–Cosine method are utilized to formulate various traveling wave solutions including bright solitons, singular solitons and periodic singular solutions. From the mathematical analysis some constraint relations are observed that guarantee the existence of solitons. Moreover, for the physical understanding of the obtained results, various 3D and 2D graphs are presented.

In this paper, we apply the undetermined coefficient method and modified mapping method to extract the bright, dark, singular, periodic singular, dark-singular combo solitons of Biswas-Arshed equation (BAE) in birefringent fibers. Many new exact solutions are acquired by proposed techniques. The computation effort and constructed exact solutions validate the effectiveness, easiness, and impact of the current techniques.

The article addresses the modeling and performance analysis of wireless sensor network localization with direct-sequence spread-spectrum signals and network-based, time difference of arrival measurements. Realistic radio channel propagation and interference conditions are taken into account. Synchronization by means of a delay-locked loop is adopted for sensor signal tracking at the wireless sensor network anchor nodes. A comprehensive timing estimation analysis is presented with channel impairments, including pathloss attenuation, shadowing, multipath fading, and multi-access interference. The full statistics of the delay-locked loop tracking jitter are derived, which serves to assess the practically achievable synchronization accuracy and its variability with radio channel conditions and specific sensor location. The time difference of arrival measurements are then used for sensor localization based on an efficient iterative maximum likelihood estimation approach shown to outperform weighted least squares methods. Numerical results are presented to quantify the sensor localization accuracy limits, showing that the error is not uniform but varies considerably across the coverage region depending on the relative sensor position with respect to the different anchor nodes. Various factors related to changing wireless sensor network topologies and network loading conditions are also considered and their impact on localization performance is quantified.

In this paper, we develop the weighted energy estimates for arbitrary 4-convex vectors and the vectors having both 4-convex and 4-concave functions as their arguments. To do this, we first develop these estimates for smooth 4-convex vectors and then, through mollification, extend the results for arbitrary 4-convex vectors. This type of estimates are valuable in problems of financial mathematics for the establishment of optimal investment strategies

This paper study the dynamics of optical solitons for nonlinear directional couplers. This coupler system is considered with the group velocity dispersion and the cross-phase modulation of two components along with the spatiotemporal dispersion coefficients. The constraint conditions for the existence of optical Gaussons and dark solitons are listed under the log law and Kerr law nonlinearities, repectively. Additionally, a couple of other solutions known as singular periodic and combined dark-singular solitons, fall out as a by-product of this scheme. This scheme however fails to retrieve bright soliton solution.

This paper scrutinizes the newly proposed Biswas-Arshed equation with Kerr and power law nonlinearities for soliton propagation through optical fibers, with small group velocity dispersion and in absence of self-phase modulation. Spatio-temporal dispersions of higher order are considered in compensation with group velocity dispersion. In this work, bright, dark, singular and bright-singular combo soliton solutions are retrieved using undetermined coefficients and Kudryashov's methods.

This paper investigates the soliton solutions of Kundu–Eckhaus equation for birefringent fibers, by employing two resourceful integration techniques, which are extended (G′/G)-expansion method and extended direct algebraic method. Variety of exact traveling wave solutions are obtained through these integration schemes. These solutions include singular solitons, dark-singular solitons, rational solutions, combination of hyperbolic functions and trigonometric functions. Whereas, periodic singular solutions are obtained as by product of these methods. Some constraint relations pop out naturally that guaranty the existence of these solutions.

This work is about highly dispersive optical solitons with Kerr law, quadratic-cubic law and non-local nonlinearities. The Kudryashov's method implemented in this paper to find the unique optical closed form of solutions. The method under consideration is consistent, effectual and can be used to establish new exact solitons of different types of PDEs arising in nonlinear optic.

In this work, the Biswas–Arshed model with Kerr law nonlinearity in the absence of self-phase modulation (SPM) and where group velocity dispersion (GVD) is insignificantly small, is studied for optical solitons using the sustained effort of several forms of mapping methods. Both spatio-temporal dispersion of third and second order are comprised to balance this model for low group velocity dispersion. When the modulus m of the Jacobi elliptic functions approaches 0 and 1, the solutions are derived in terms of trigonometric functions and hyperbolic functions respectively. From this scheme singular, dark and bright soliton solutions appear.

The aim of study of this article is to determine the solution of seventh order boundary value problem. The behavior of the induction motor is simulated by fifth order differential equation model and induction machine with two rotor circuits is represented by the seventh order differential equations. In this study, a Reproducing Kernel Method (RKM) for a class of seventh-order nonlinear boundary value problems is investigated. The argument is based on the reproducing kernel space W 8 2 (0, 1). The proposed method gives better results when compared with the method available in literature (Siddiqi et al., 2012a). Two numerical examples are given to illustrate the implementation and efficiency of the method.

In this paper, we proposed new results in quadruple Laplace transform and proved some properties concerned with quadruple Laplace transform. We also developed some applications based on these results and solved homogeneous as well as non-homogeneous partial differential equations involving four variables. The performance of quadruple Laplace transform is shown to be very encouraging by concrete examples. An elementary table of quadruple Laplace transform is also provided.

Aims: In this paper an approximate method for the solution of third-order differential equation with two and three point boundary condition is developed using iterative reproducing kernel method. Methods: The third order boundary value problem is converted into integro-differential equation of second order two point boundary value problem. The reproducing kernel method which takes the form of a convergent series with easily computable components is used for the solution of second order two point boundary value problem. Results: Six numerical examples are given to demonstrate the efficiency of the present method. The results obtained are better than the existing methods developed in [19,20,21,22,23]. Conclusions: In this paper, the solution of linear and nonlinear third order (two and three point) boundary value problem is determined. For the solution of third order three point boundary value problem reproducing kernel method is proposed and obtained a good accuracy in absolute errors. As the reproducing kernel method cannot solve the third order three-point boundary value problems directly, so the third order boundary value problem is converted to second order two point boundary value problem after absorbing the nonlocal condition at . The method developed is compared with those developed by Li et al. [19], El-Salam et al. [20], Khan and Aziz [21], Li and Wu [22] and Wu and Li [23]. As observed in Example 3, 4, 5 and 6 that the method obtained in this paper is better than [19]-[23]. Results obtained using the scheme presented here show that the numerical scheme is very effective and convenient for third-order linear as well as nonlinear boundary value problem.

Multiple risk factors can be modified to decrease asthma incidence. It is important to understand early risks to decrease exposure to harmful conditions in the environment that can trigger asthma which may not be clinically evident in children until they reach adulthood. A retrospective literature review of articles on the prevalence of asthma in the urban versus rural environment was initiated in order to understand the effect of the environment on asthma. The urban-living effect is a global problem in the face of growing population, industrialization and pollution. The socioeconomic dichotomy in the urban versus rural environment also affects access and quality of health care. Articles reviewed had differences in the urban versus rural prevalence of asthma. However, further analysis of specific risk factors and socioeconomic trends that increased susceptibility to asthma was the same in these studies. Some rural areas may have similar environmental and socioeconomic issues that place them at the same risk for the development of asthma as their urban counterparts. Urban locations generally tend to have the prototype environment that can lead to the predisposition of asthma. Ultimately, the incidence of asthma can be decreased if these environmental and socioeconomic issues are addressed. However, every effort is needed from the level of the individual to the community at large.

Introduction Serotonin syndrome is a potentially life-threatening condition caused by excessive serotonergic activity in the central nervous system. It is characterized by mental status changes (eg, confusion, agitation, lethargy, coma), autonomic instability (eg, hyperthermia, tachycardia, diaphoresis, nausea, vomiting, diarrhea, dilated pupils), and neuromuscular hyperactivity (eg, myoclonus, hyperreflexia, rigidity, trismus). Serotonin syndrome classically occurs in patients receiving two or more serotonergic drugs, but it can occur with monotherapy. We report a case of a 20-year-old man who developed serotonin syndrome resulting from overdose of Escitolapram with concomitant use of cocaine. It is a very important area in medicine as serotonin syndrome should be suspected especially in drug abusers who are being treated with psychotropic agents for mental illnesses.

In this manuscript, we explore the existence of wormhole solutions exhibiting spherical symmetry in a modified gravity namely $f(R,T)$ theory by involving some aspects of non-commutative geometry. For this purpose, we consider the anisotropic matter contents along with the well-known Gaussian and Lorentizian distributions of string theory. For the sake of simplicity in analytic discussions, we take a specific form of $f(R,T)$ function given by $f(R,T)=R+\lambda T$. For both these non-commutative distributions, we get exact solutions in terms of exponential and hypergeometric functions. By taking some suitable choice of free parameters, we investigate different interesting aspects of these wormhole solutions graphically. We also explored the stability of these wormhole models using equilibrium condition. It can be concluded that the obtained solutions are stable and physically viable satisfying the wormhole existence criteria. Lastly, we discuss the constraints for positivity of the active gravitational mass for both these distributions., Comment: 12 pages, 8 figures

In this paper, we construct exact families of traveling wave (periodic wave, solitary wave, shock wave, singular-wave, singular-periodic wave, and singular-solitary wave) solutions of a well-known system of nonlinear PDEs, the Wu–Zhang system, which describes (1[Formula: see text]+[Formula: see text]1)-dimensional dispersive long waves. This system is solved by using the generalized [Formula: see text] expansion method, where G satisfies the Jacobi elliptic equation of fourth order. Meanwhile, the mechanical features of some families are explained through three-dimensional figures.

In this research paper, we address the issues of expansion and gravitational collapse of anisotropic spherical source in the presence of cosmological constant. For this purpose, we have solved the Einstein field equations with gravitating source and cosmological constant. The absence of radial heat flux in the gravitating source provide the parametric form of two-metric functions in terms of a single-metric function. The expansion scalar and the mass function of the gravitating source is evaluated for the given metric. The trapping condition is applied to mass function which implies the existence of horizons, like the horizons of Schwarzschild de-Sitter black holes. The trapping condition provides the parametric form of the unknown metric function. The value of expansion scalar has been analyzed in detail to see its positivity and negativity, which correspond to expansion and collapse, respectively. So, the values of parameter [Formula: see text] for which expansion scalar is positive have been used to analyze the other physical variables including density, pressures and anisotropy. The same quantities have been evaluated for the values of [Formula: see text] that result in the negative values of expansion scalar leading to collapse. The effects of positive cosmological constant have been noted in both expansion and collapse solutions. Due to the presence of cosmological constant after collapse, there would occur inner and outer horizons or a unique horizon depending on the value of mass of the gravitating source.

Physical device modelling of a monolithic CdZnO based double quantum well LED is presented. The aim of this paper is to achieve an LED structure with enhanced Internal Quantum Efficiency (IQE) and Full Width at Half Maximum (FWHM) by optimizing two active layers. The proposed LED structure contains dual quantum well of CdZnO material which emits light in Violet (400nm) spectrum. Physical device modelling and characterization of the structure is done by using industrial standard device simulation software Silvaco TCAD. Results of Electron Hole Concentration and Radiative Recombination Rate shows efficient carrier confinement in active region of structure. IQE upto 95% and FWHM of 14.7nm is achieved by optimizing cadmium composition in CdZnO active layers, doping concentrations and thicknesses of barrier layers.