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To use the modified decomposition method to obtain numerical solutions of fourth‐order boundary value problems.

The modified form of Adomian decomposition method (ADM) originated by Wazwaz in 1997/1998 is considered and applied. In addition, a comparison of the modified decomposition method and the perturbed collocation method when applied to the solutions of fourth‐order boundary value problems is presented.

The comparison of these two methods has shown that the modified or standard decomposition methods are reliable, efficient and easy to use for solving higher‐order boundary value problems.

This study provides both an analysis of the method as well as a comparison of the numerical solutions of fourth‐order boundary value problems. Future research in the application of this methodology to other areas should prove productive.

The numerical results, using the modified technique, were obtained from selected fourth‐order boundary value problems which were linear and non‐linear problems.

Assesses, by comparison, methods for the numerical solutions of fourth‐order boundary value problems. Shows through original numerical results the value of the modified or standard decomposition methods in the solution of these problems.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

The paper presents a numerical technique for the simulation of the effects of grey‐diffusive surface radiation on fluid flow using a finite volume procedure for two‐dimensional (plane and axi‐symmetric) geometries. The governing equations are solved sequentially, and the non‐linearities and coupling of variables are accounted for through outer iterations (coefficients updates). In order to reduce the number of outer iterations, a multigrid algorithm was implemented. The radiating surface model assumes a non‐participating medium, semi‐transparent walls and constant elementary surface temperature and radiation fluxes. The calculation of view factors is based on the analytical evaluation for the plane geometry and numerical integration for axi‐symmetric geometry. Ashadowing algorithm was implemented for the calculation of view factors in general geometries. The method for the calculation of view factors was first tested by comparison with available analytical solutions for a complex geometric configuration. The flow prediction code combined with radiation heat transfer was verified by comparisons with analytical one‐dimensional solutions. Further test calculations were done for the flow and heat transfer in a cavity with a radiating submerged body. As an example of the capabilities of the method, transport processes in metalorganic chemical vapour deposition (MOCVD) reactors were simulated.

An adaptive grid solution method is described for computing the time accurate solution of an unsteady flow problem. The solution method consists of three parts: a grid point redistribution method; an unsteady Euler equation solver; and a temporal coupling routine that links the dynamic grid to the flow solver. The grid movement technique is a direct curve by curve method containing grid controls that generate a smooth grid that resolves the severe solution gradients and the sharp transitions in the solution gradients. By design, the temporal coupling procedure provides a grid that does not lag the solution in time. The adaptive solution method is tested by computing the unsteady inviscid solutions for a one‐dimensional shock tube and a two‐dimensional shock vortex interaction. Quantitative comparisons are made between the adaptive solutions, theoretical solutions and numerical solutions computed on stationary grids. Test results demonstrate the good temporal tracking of the solution by the adaptive grid, and the ability of the adaptive method to capture an unsteady solution of comparable accuracy to that computed on a stationary grid containing significantly more grid points than used in the adaptive grid.

The purpose of this paper is the comparative analysis of Haar Wavelet Method and Optimal Homotopy Asymptotic Method for fractional Fisher type equation. In this paper, two reliable techniques, Haar wavelet method and optimal homotopy asymptotic method (OHAM), have been presented. The Haar wavelet method is an efficient numerical method for the numerical solution of fractional order partial differential equation like the Fisher type. The approximate solutions of the fractional Fisher-type equation are compared with those of OHAM and with the exact solutions. Comparisons between the obtained solutions with the exact solutions exhibit that both the featured methods are effective and efficient in solving nonlinear problems. However, the results indicate that OHAM provides more accurate value than the Haar wavelet method.

Comparisons between the solutions obtained by the Haar wavelet method and OHAM with the exact solutions exhibit that both featured methods are effective and efficient in solving nonlinear problems.

The comparative results indicate that OHAM provides a more accurate value than the Haar wavelet method.

In this paper, two reliable techniques, the Haar wavelet method and OHAM, have been proposed for solving nonlinear fractional partial differential equation, i.e. fractional Fisher-type equation. The proposed novel methods are well suited for only nonlinear fractional partial differential equations. It also exhibits that the proposed method is a very efficient and powerful technique in finding the solutions for the nonlinear time fractional differential equations. The main significance of the proposed method is that it requires less amount of computational overhead in comparison to other numerical and analytical approximate methods. The application of the proposed methods for the solutions of time fractional Fisher-type equations satisfactorily justifies its simplicity and efficiency.

The performance of Ardalan′s heuristic is compared with that of Teitz and Bart for the location of service facilities, where performance is assessed in terms of the accuracy of solutions. The comparison is made considering two kinds of location problem: p‐median and p‐median with maximum distance constraints. The results indicate that the Teitz and Bart method generally produces a better solution than the Ardalan method for both problems.

Considering typical self‐adjoint and non‐self‐adjoint problems that are governed by differential equations with predominant lower order derivatives, a comparison is presented of their finite element solutions by Ritz, Galerkin, least square (LSQ) and discrete least square (DLSQ) methods.

The purpose of this paper is to evaluate the impact of different Additive Manufacturing (AM) orientations on the structural behavior of topologically optimized wings for Unmanned Aerial Systems (UAS), which might enable lightweight and low cost, yet complex, wing structural designs.

Based on an aerodynamic load, a two dimensional NACA0012 airfoil is topologically optimized considering PolyLatic Acid (PLA), several volume fractions and different manufacturing orientations. Then, the resulting topologies are post-processed to allow for manufacturing and extrude to three dimensional wing geometries with constant cross-sections. These wings are then manufactured using Fusion Deposition Modeling (FDM) technology and their dynamic structural behavior analyzed by means of Experimental Modal Analysis (EMA) in the linear elastic region.

Volume fraction increase is observed to improve the structural performance without increasing the manufacturing time. Despite manufacturing the wing from the leading edge to the trailing edge can reduce manufacturing time using FDM technology, it is found to be more difficult to build.

This research is a contribution toward the design and built of lightweight and low cost wings for UAS.

The purpose of this paper is to expand understandings of how logistics can reduce food waste in food supply chains (FSCs).

Using a research framework that associates causes of food waste with logistics solutions, a multiple-case study was conducted in three Swedish FSCs of meat, fruit and vegetables, and ambient products, respectively, and involving industrial producers, wholesalers, and retailers. Data were collected during 19 semistructured interviews and four site visits, and logistics solutions were analysed according to logistics activities, actors involved and their stages in the FSC, and coordination mechanisms.

A joint analysis of nine logistics solutions revealed that to efficiently reduce food waste in FSCs, solutions have been implemented at three stages of FSCs, as well as that those solutions differ in their integration of six logistics activities and four coordination mechanisms. The findings moreover indicate that the solutions are interlinked, thereby implying that coordination is necessary both within solutions as well as among them.

The chief limitation is that the potential of the identified logistics solutions is not quantified.

The paper makes recommendations for reducing food waste in FSCs by developing new solutions and modifying existing ones.

The paper suggests ways to reduce significant environmental impacts of food waste.

By building upon previous research explaining causes of food waste, this paper focusses on logistics solutions for reducing such waste.