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This paper analyzes the dynamics of soliton transmission to the newly proposed Biswas-Arshed model which is considered in the absence of self-phase modulation. To compensate the negligibly small group velocity dispersion, this model includes spatio-temporal dispersion of higher order. The extended (G′/G)-expansion method is employed to retrieve singular, dark and periodic singular soliton solutions for the two nonlinear forms of the model which are Kerr and power law. The constraint relations for the existence of these solitons are also reckoned.

The image segmentation is the basic step in the image processing involved in the processing of medical images. Over the past two decades, medical image segmentation has remained a challenge for researchers while the use of this imaging modality is rapidly growing in research studies. This article surveys the techniques and their effect on chest X-ray images. The objective of this work is to study the key similarities and differences among the different published methods while highlighting their strengths and weaknesses on chest X-ray images. The reason is to assist the researchers in the choice of an appropriate lung segmentation methodology. We additionally give a complete portrayal of the existing few basic methods when combined with preprocessing method that can be utilized as a part of the segmentation. A discussion and fair analysis justified with experimental results along with quantitative correlation of the outcomes on 247 images of JSRT through Dice coefficient exhibited.

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.

The use of multi-agent systems (MAS) as a distributed control method for shop-floor manufacturing control applications has been extensively researched. MAS provides new implementation solutions for smart manufacturing requirements such as the high dynamism and flexibility required in modern manufacturing applications. MAS in smart manufacturing is becoming increasingly important to achieve increased automation of machines and other components. Emerging technologies like artificial intelligence, cloud-based infrastructures, and cloud computing can also provide systems with intelligent, autonomous, and more scalable solutions. In the current work, a decision-making framework is proposed based on the combination of MAS cloud computing, agent technology, and machine learning. The framework is demonstrated in a quality control use case with vision inspection and agent-based control. The experiment utilizes a cloud-based machine learning pipeline for part classification and agent technology for routing. The results show the applicability of the framework in real-world scenarios bridging cloud service-oriented architecture with agent technology for production systems.

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.

The trend in seismic acquisition is geared toward high geophone densities. Future node densities are expected to be on the order of 1M nodes, leading to a huge aggregate data rate in the geophone array and requiring the use of some form of signal compression. This work presents a family of signal compression algorithms based on vector quantization and its transposition to the infinite-dimensional case—functional quantization (FQ). Using FQ, we quantize the entire sample path of the seismic waveform in a target function space, instead of quantizing individual samples. The polynomial design and computational complexity afforded by FQ allow for online training of codebooks where the statistics of the seismic wavefield may be changing. An efficient algorithm for the construction of a functional quantizer is given. It is based on Monte Carlo simulation to circumvent the curse of high dimensionality and avoids explicit construction of Voronoi regions to tessellate the function space of interest. In the sequel, we augment our basic FQ architecture with three different VQ techniques in the literature. The augmentation yields hybridized FQ strategies. These hybrid quantization algorithms are: (1) FQ-classified VQ, (2) FQ-residual/multistage VQ and (3) FQ-recursive VQ. The joint quantizers are obtained by replacing regular VQ codebooks in these hybrid quantizers by their FQ equivalents. Simulation results show that the FQ combined with these different VQ techniques performs better in the rate–distortion sense than either FQ alone or the aforementioned VQ techniques in isolation.

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.

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.

Due to the exponential growth in technologies and a greater number of competitors in the telecom sector, the companies are facing a rigorous problem of customer churns. The customer churn is a phenomenon that highlights the customer’s intention who may switch from a certain service or even the service provider company. Many customer churn prediction (CCP) techniques are developed by academics and practitioners to handle the customer churn in order to resolve the problems pertaining to customer retention. However, CCP is not widely studied in the scenario where the company is not having enough historical data due to either been a newly established company or due to the recent start of a new technology or even because of the loss of the historical data. The just-in-time (JIT) approach can be a more practical alternative to address this issue as compared to state-of-the-art CCP techniques. Unfortunately, similar to traditional churn prediction models, JIT also requires enough historical data. To address this gap in the traditional CCP models, this study uses the cross-company data, i.e., data from another company, in the context of JIT for addressing CCP problems in the telecom sector. We empirically evaluated the performance of the proposed model using publicly available datasets of two telecom companies. It is found from the empirical evaluation that in the JIT-CCP context: (i) it is possible to evaluate the performance of the predictive model using cross-company dataset for training purposes and (ii) it is evident that heterogeneous ensemble-based JIT-CCP model is more suitable approach to use as compared to individual classifier or homogeneous ensemble-based technique.

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.

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 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.

In this work we develop the square integral estimates for the functions of n variables which are subharmonic with respect to some variables and for other remaining variables are superharmonic. It is in a sense a generalization of reverse Poincaré type inequalities for the difference of superharmonic functions developed in (J. Inequal. Appl. 2015: doi:10.1186/s13660-015-0916-9 , 2015).

Internet of things grew swiftly and many services, software, sensors-embedded electronic devices and related protocols were developed and still in progress with full swing. Internet of things enabling physically existing things to see, hear, think and perform a notable task by allowing them to talk to each other and share useful information while making decision and caring-on/out their important tasks. Internet of things is greatly promoted by wireless sensor network as it becomes a perpetual layer for it. Wireless sensor network works as a base-stone for most of the Internet of things applications. There are severe general and specific threats and technical challenges to Internet of things–based sensor networks which must overcome to ensure adaptation and diffusion of it. Most of the limitations of wireless sensor networks are due to its resource constraint objects nature. The specified open research challenges in Internet of things–based sensor network are power consumption, network lifespan, network throughput, routing and network security. To overcome aforementioned problems, this work aimed to prolong network lifetime, improve throughput, decrease packet latency/packet loss and further improvise in encountering malicious nodes. To further tune the network lifetime in terms of energy, wireless harvesting energy is suggested in proposed three-layer cluster-based wireless sensor network routing protocol. The proposed mechanism is a three-tier clustering technique with implanted security mechanism to encounter malicious activities of sensor nodes and to slant them into blacklist. It is a centred-based clustering protocol, where selection of cluster head and grid head is carried out by sink node based on the value of its cost function. Moreover, hardware-based link quality estimators are used to check link effectiveness and to further improve routing efficiency. At the end, excessive experiments have been carried out to check efficacy of the proposed protocol. It outperforms most of its counterpart protocols such as fuzzy logic–based unequal clustering and ant colony optimization–based routing hybrid, Artificial Bee Colony-SD, enhanced three-layer hybrid clustering mechanism and energy aware multi-hop routing in terms of network lifetime, network throughput, average energy consumption and packet latency.

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.

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.

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 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 article, the modified direct algebraic method has been extended to celebrate the new complex travelling wave solutions of nonlinear evolution equations of fractional order. For finding solutions, the fractional complex transformation has been implemented to convert nonlinear partial fractional differential equations into nonlinear ordinary differential equations. After this, the modified direct algebraic method has been applied successfully, to construct the complex travelling wave solutions. As far as concerned about the applications, the nonlinear time-space fractional KdV, foam drainage and coupled burgers' equations of fractional order have been considered.

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.

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.

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.

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.

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.

The present research work introduces a recirculated airlift bioreactor (biocontactor), which combines advantages of packed bed and external loop airlift bioreactors. This bioreactor is characterized by an internal gas redistributor placed between two beds of packing in the riser while working fluid recirculates through an external downcomer. The main objective of this research work was to characterize the mixing hydrodynamics of this reactor through the non-intrusive flow visualization technique of electrical resistance tomography (ERT). The tomography images were employed to examine the effects of packing, gas redistributor, sparger configuration, gas flow rate, and liquid height on the mixing time and superficial liquid velocity. Results showed that the mixing time in the bioreactor was decreased with an increase in the superficial gas velocity in the riser. It was found that at a constant riser superficial gas velocity, the mixing time was increased and the superficial liquid velocity decreased when a cross shaped sparger was replaced by a circular sparger, which had the same diameter, and the same number and size of holes. Results also showed that mixing time increased and the superficial liquid velocity decreased by reducing the liquid height in the bioreactor, in addition to installing the internal gas redistributor and packing in the riser. The presence of the internal gas redistributor and packing reduced the cross-sectional area available for flow and increased resistance in the liquid flow path. Results, which were obtained from this study, can be utilized to improve mixing in external loop airlift bioreactors for wider range of applications.