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The paper aims to design a process to mechanize traditional chasing and repoussé which is the art of creating an artistic pattern on a sheet metal by making high and low points through utilization of hammer and chisel. In scientific literature, it is a kind of incremental sheet metal forming.

In the designed process, a magnetic actuator is used as a hammer which converts electric energy into kinetic reciprocal impact energy, and hammering sequence is completely controlled via the designed software. The sheet is bound not to move easily. Then, a hammering mechanism is connected to the numerical control machine. As the magnetic hammer is moved gradually along the defined path, the sheet is chased gradually by controlling the consecutive impacts. Different methods of test sheet entanglement are also discussed to reduce noise and undesired deformations of sheet, and indents are also clarified.

The designed mechanism enables the user to form desired art patterns faster with more precision via the automated process. The hammering sequence is controlled via computer successfully. The designed magnetic actuator could be commercialized easily. Experiments show that the pitch under sheet is the best. Typical art patterns are chased successfully.

In incremental sheet metal punching, there was no control on hammering sequence before. In this process, the designed magnetic hammer is quite controllable. Also, it is easily attached to the computerized numerical control (CNC) and is suitable for commercial use. Furthermore, the stuff under sheet was not taken into consideration before.

The purpose of this paper is to demonstrate that the numerical method is not everything for nonlinear equations. Some properties cannot be revealed numerically; an example is used to elucidate the fact.

A variational principle is established for the generalized KdV – Burgers equation by the semi-inverse method, and the equation is solved analytically by the exp-function method, and some exact solutions are obtained, including blowup solutions and discontinuous solutions. The solution morphologies are studied by illustrations using different scales.

Solitary solution is the basic property of nonlinear wave equations. This paper finds some new properties of the KdV–Burgers equation, which have not been reported in open literature and cannot be effectively elucidated by numerical methods. When the solitary solution or the blowup solution is observed on a much small scale, their discontinuous property is first found.

The variational principle can explain the blowup and discontinuous properties of a nonlinear wave equation, and the exp-function method is a good candidate to reveal the solution properties.

This paper aims to propose a policy prioritization framework in view of a layered scenario building along with key stakeholder analysis and has been applied in a case study to determine the priority of Iran environmental policies at the horizon of 2030. A creative framework that covers future scenarios and allows for a more accurate and intelligent policy assessment and prioritization.

The general environmental policies of the Islamic Republic of Iran are evaluated, and observation policies in social area were identified. Causal layered analysis (CLA) is applied for policy prioritization based on layered probable scenarios and key stakeholder role consideration. The Multiple-criteria decision-making (MCDM) is also used for ranking General Environmental Policies by the technique for order of preference by similarity to ideal solution (TOPSIS).

Four uncertainties were obtained in different layers based on the CLA analysis, resulting in the creation of four main scenario and 16 discrete scenarios. Finally, Iran’s environmental policies were prioritized given the probable scenarios and the centralized policies on the social and political domains. The proposed model will be effective in policy-making in multilateral atmosphere to prioritize policies and alternative macro-strategies.

This paper shows that foresight and especially developed scenarios provide intelligent, efficient and effective planning and policy-making, and in addition to illustrating surrounding changes and probable future imagery, it generates common understanding and inter-subjective knowledge by increasing participation of various officials and stakeholders.

The purpose of this paper is to find an approximate solution of a fractional differential equation. The fractional Newell–Whitehead–Segel equation (FNWSE) is used to elucidate the solution process, which is one of the nonlinear amplitude equation, and it enhances a significant role in the modeling of various physical phenomena arising in fluid mechanics, solid-state physics, optics, plasma physics, dispersion and convection systems.

In Part 1, the authors adopted Mohand transform to find the analytical solution of FNWSE. In this part, the authors apply the fractional complex transform (the two-scale transform) to convert the problem into its differential partner, and then they introduce the homotopy perturbation method (HPM) to bring down the nonlinear terms for the approximate solution.

The HPM makes numerical simulation for the fractional differential equations easy, and the two-scale transform is a strong tool for fractal models.

The HPM with the two-scale transform sheds a bright light on numerical approach to fractional calculus.

This study aims to introduce a modern higher efficiency predictor–corrector iterative algorithm.

Furthermore, the efficiency of new algorithm is analyzed on the based on Chun-Hui He’s iteration method.

In comparison with the current robust algorithms, the newly establish algorithm behaves better and efficient, whereas the current existing algorithm fails or slows in the considered test examples.

The modified Chun-Hui He’s algorithm has great practical implication in numerous real-life challenges in different area of engineering, such as Industrial engineering, Civil engineering, Electrical engineering and Mechanical engineering.

The paper presents a modified Chun-Hui He’s algorithm for solving the nonlinear algebraic models exist in various area.

The purpose of this study is to develop an efficient numerical procedure for simulating the effect of printing orientation, as one of the primary sources of anisotropy in 3D-printed components, on their fracture properties.

The extended finite element method and the cohesive zone model (XFEM-CZM) are used to develop subroutines for fracture simulation. The ability of two prevalent models, i.e. the continuous-varying fracture properties (CVF) model and the weak plane model (WPM), and a combination of both models (WPM-CVF) are evaluated to capture fracture behavior of the additively manufactured samples. These models are based on the non-local and local forms of the anisotropic maximum tangential stress criterion. The numerical models are assessed by comparing their results with experimental outcomes of 16 different configurations of polycarbonate samples printed using the material extrusion technique.

The results demonstrate that the CVF exaggerates the level of anisotropy, and the WPM cannot detect the mild anisotropy of 3D-printed parts, while the WPM-CVF produces the best results. Additionally, the non-local scheme outperforms the local approach in terms of finite element analysis performance, such as mesh dependency, robustness, etc.

This paper provides a method for modeling anisotropic fracture in 3D-printed objects. A new damage model based on a combination of two prevalent models is offered. Moreover, the developed subroutines for implementing the non-local anisotropic fracture criterion enable a reliable crack propagation simulation in media with varying degrees of complication, such as anisotropy.

The purpose of this paper is to investigate the feasibility of solving turbulent flows based on smoothed finite element method (S-FEM). Then, the differences between S-FEM and finite element method (FEM) in dealing with turbulent flows are compared.

The stabilization scheme, the streamline-upwind/Petrov-Galerkin stabilization is coupled with stabilized pressure gradient projection in the fractional step framework. The Reynolds-averaged Navier-Stokes equations with standard k-epsilon model are selected to solve turbulent flows based on S-FEM and FEM. Standard wall functions are applied to predict boundary layer profiles.

This paper explores a completely new application of S-FEM on turbulent flows. The adopted stabilization scheme presents a good performance on stabilizing the flows, especially for very high Reynolds numbers flows. An advantage of S-FEM is found in applying wall functions comparing with FEM. The differences between S-FEM and FEM have been investigated.

The research in this work is limited to the two-dimensional incompressible turbulent flow.

The verification and validation of a new combination are conducted by several numerical examples. The new combination could be used to deal with more complicated turbulent flows.

The applications of the new combination to study basic and complex turbulent flow are also presented, which demonstrates its potential to solve more turbulent flows in nature and engineering.

This work carries out a great extension of S-FEM in simulations of fluid dynamics. The new combination is verified to be very effective in handling turbulent flows. The performances of S-FEM and FEM on turbulent flows were analyzed by several numerical examples. Superior results were found compared with existing results and experiments. Meanwhile, S-FEM has an advantage of accuracy in predicting boundary layer profile.

This study aims that very lately, Mohand transform is introduced to solve the ordinary and partial differential equations (PDEs). In this paper, the authors modify this transformation and associate it with a further analytical method called homotopy perturbation method (HPM) for the fractional view of Newell–Whitehead–Segel equation (NWSE). As Mohand transform is restricted to linear obstacles only, as a consequence, HPM is used to crack the nonlinear terms arising in the illustrated problems. The fractional derivatives are taken into the Caputo sense.

The specific objective of this study is to examine the problem which performs an efficient role in the form of stripe orders of two dimensional systems. The authors achieve the multiple behaviors and properties of fractional NWSE with different positive integers.

The main finding of this paper is to analyze the fractional view of NWSE. The obtain results perform very good in agreement with exact solution. The authors show that this strategy is absolutely very easy and smooth and have no assumption for the constriction of this approach.

This paper invokes these two main inspirations: first, Mohand transform is associated with HPM, secondly, fractional view of NWSE with different positive integers.

In this paper, the graph of approximate solution has the excellent promise with the graphs of exact solutions.

This paper presents valuable technique for handling the fractional PDEs without involving any restrictions or hypothesis.

The authors discuss the fractional view of NWSE by a Mohand transform. The work of the present paper is original and advanced. Significantly, to the best of the authors’ knowledge, no such work has yet been published in the literature.

Various individual and environmental factors influencing employees’ online knowledge sharing have been identified, but the understanding regarding these has been mostly limited because of their independent and direct effects our understanding has been mostly limited to their independent and direct effects. This study aims to propose that the fit between employees and their environments (PE fit) matters. A model explaining how PE fit and misfit affect employees’ knowledge sharing behavior through influencing their affective commitment is developed and assessed.

The proposed model was assessed with data collected in a survey of 218 employees.

Results indicate that PE fit in the norm of collaboration, innovativeness and skill variety leads to the development of stronger affective commitment and, therefore, more knowledge sharing behavior than when they are in shortfall or excess in the environment (i.e. PE misfit).

The findings indicate a new direction for knowledge sharing research that focuses on PE fit and suggest that knowledge sharing can be improved more proactively in practice by assessing PE fit during recruitment.