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The cell‐based method of domain decomposition was first introduced for complex 3D geometries. To further assess the method, the aim is to carry out flow simulation in rectangular ducts to compare the known analytical solutions.

The method is not based on equal subvolumes but on equal numbers of active cells. The variables of the simulation are stored in ordered 1D arrays to replace the conventional 3D arrays, and the domain decomposition of the complex 3D problems therefore becomes 1D. Finally, the 3D results can be recovered using a coordinate matrix. Through the flow simulation in the rectangular ducts how the algorithm of the domain decompositions works was illustrated clearly, and the numerical solution was compared with the exact solutions.

The cell‐based method can find the subdomain interfaces successfully. The parallelization based on the algorithm does not cause additional errors. The numerical results agree well with the exact solutions. Furthermore, the results of the parallelization show again that domains of 3D geometries can be decomposed automatically without inducing load imbalances.

Although, the approach is illustrated with lattice Boltzmann method, it is also applicable to other numerical methods in fluid dynamics and molecular dynamics.

Unlike the existing methods, the cell‐based method performs the load balance first based on the total number of fluid cells and then decomposes the domain into a number of groups (or subdomains). Thus, the task of the cell‐based method is to recover the interface rather than to balance the load as in the traditional methods. This work has examined the celled‐based method for the flow in rectangular ducts. The benchmark test confirms that the cell‐based domain decomposition is reliable and convenient in comparison with the well‐known exact solutions.

Manufacturing facilities may simplify their operations by converting from a process‐based layout to manufacturing cells. Mathematically, many possible configurations of cells exist, so it may prove computationally infeasible to analyse them all. Also, some current methods of cell design do not take account of the pattern of demand of the existing products or the sequence of the operations that are performed on the products. Presents a simple method of designing manufacturing cells, which uses product demand and operations sequence to design feasible cells, while remaining computationally simple. The method uses a standard spreadsheet tool, so is accessible to a wide range of manufacturing facilities. The method is illustrated with an actual application to a press shop manufacturing over 200 products on 20 presses.

The design of a cellular manufacturing system requires that a machine population be partitioned into machine groups called manufacturing cells. A new graph partitioning heuristic is proposed to solve the manufacturing cell formation problem (MCFP). In the proposed heuristic, The MCFP is represented by a graph whose node set represents the machine cluster and edge set represents the machine‐pair association weights. A graph partitioning approach is used to form the manufacturing cells. This approach offers improved design flexibility by allowing a variety of design parameters to be controlled during cell formation. The effectiveness of the heuristic is demonstrated by comparing it to two MCFP published solution methods using several problems from the literature.

A new method for the determination of the classical Preisach’s model distribution function is developed. The proposed method determines numerically the distribution function from classical experimental measurements and does not make any assumption concerning the material type. The Preisach’s triangle is discretised in a finite set of cells (about 200 cells are needed). Two ways for the determination of the discretised distribution function are presented. The first assumes constant distribution function value in each cell. The second determines the nodal values of the discretised distribution function and uses a bilinear interpolation technique to obtain the distribution function in any position of the Preisach’s triangle. We also show that the proposed method can also be used to model the inverse distribution function. The comparison between modelled and experimental hysteresis curves for both major and minor cycles have shown the effectiveness of the proposed method.

Without reliance on results obtained from applying a cell formation method, this paper aims to describe a simple quantitative approach to testing whether an underlying pattern of relationships exists between machines of a given system, such that the machines may be rearranged into manufacturing cells. It also aims to support the approach by an index for measuring the clustering tendency.

The eigenvalues of the similarity coefficient matrix and Kaiser's rule are used to: detect the number of clusters existing in the part‐machine matrix, and derive an index for predicting the goodness of the best possible obtainable cell formation.

The results of applying the proposed approach and the clustering tendency index to problems of different sizes taken from the literature have proven that both the approach and the clustering tendency index are powerful in performing the feasibility assessment and in predicting the right number of manufacturing cell to be formed.

This study is of considerable value to practitioners because it provides them with a powerful yet very easy to apply approach for assessing the feasibility of adopting cellular manufacturing in early stages of design. Another characteristic of this approach is the possibility of using it as a decision support tool for practitioners who opt to use a cell formation method which requires specifying the number of cells in advance. Moreover, the approach does not require any special software package, since it can be easily performed using several available software packages such as MATLAB and Mathematica.

A methodology for evaluating the adaptability of a system to cellular manufacturing has been proposed in a previous study. However, the methodology used is complex and uses a certain degree of subjectivity. In contrast, the proposed approach is simple and completely quantitative. Furthermore, a new index for measuring the clustering tendency is presented.

The purpose of this research paper is to discuss cellular manufacturing is discussed under conditions of changing product demand. Traditional cell formation procedures ignore any changes in demand over time from product redesign and other factors. However given that in today's business environment, product life cycles are short, a framework is proposed that creates a multi‐period cellular layout plan including cell redesign where appropriate.

The framework is illustrated using a two‐stage procedure based on the generalized machine assignment problem and dynamic programming. This framework is conceptually compared to virtual cell manufacturing, which is useful when there is uncertainty in demand rather than anticipated changes in demand. A case study is used to explain how the concept would work in practice.

One major characteristic of the proposed method is that it is flexible enough to incorporate existing cell formation procedures. It is shown through an example problem that the proposed two‐stage method is better than undergoing ad hoc layout changes or ignoring the demand changes when shifting or cell rearrangement costs exist. It also sheds some insight into cellular manufacturing under dynamic conditions.

This paper should be useful to both researchers and practitioners who deal with demand changes in cellular manufacturing.

To design a flexible integrated robotic assembly and rework (remanufacturing) cell for assembly, selective assembly and rework of advanced surface mount components (SMCs) using the generic methodology developed in this paper.

Manual rework procedures are investigated for all advanced SMCs. General and specific component‐related rework considerations are obtained and necessary tooling candidates for automation are determined. This is followed by determination of the specific automated rework procedure and selection of suitable tooling for automated robotic rework and generation and evaluation of design concepts.

The developed methodology, which considers the reflow tool at the centre of the development process, has worked well in designing a flexible integrated robotic assembly and rework cell.

This study identified the rework requirements for advanced SMCs, the essential features for rework reflow tools, criteria for comparing reflow tools, and a generic procedure for design and concept selection.

It provides valuable knowledge for designers of flexible integrated robotic assembly and rework cells for assembly, selective assembly and rework of advanced SMCs.

The purpose of this paper is to examine the effects of user-defined parameters settings (e.g. interpolation method, grid cell size, and bandwidth) on the predictive accuracy of crime hotspot maps produced from kernel density estimation (KDE).

The influence of variations in parameter settings on prospective KDE maps is examined across two types of interpersonal violence (e.g. aggravated assault and robbery) and two types of property crime (e.g. commercial burglary and motor vehicle theft).

Results show that interpolation method has a considerable effect on predictive accuracy, grid cell size has little to no effect, and bandwidth as some effect.

The current study advances the knowledge and understanding of prospective hotspot crime mapping as it answers the calls by Chainey et al. (2008) and others to further investigate the methods used to predict crime.

This paper aims to provide a comprehensive review of the state-of–the-art design methods for additive manufacturing (AM) technologies to improve functional performance.

In this survey, design methods for AM to improve functional performance are divided into two main groups. They are design methods for a specific objective and general design methods. Design methods in the first group primarily focus on the improvement of functional performance, while the second group also takes other important factors such as manufacturability and cost into consideration with a more general framework. Design methods in each groups are carefully reviewed with discussion and comparison.

The advantages and disadvantages of different design methods for AM are discussed in this paper. Some general issues of existing methods are summarized below: most existing design methods only focus on a single design scale with a single function; few product-level design methods are available for both products’ functionality and assembly; and some existing design methods are hard to implement for the lack of suitable computer-aided design software.

This study is a useful source for designers to select an appropriate design method to take full advantage of AM.

In this survey, a novel classification method is used to categorize existing design methods for AM. Based on this classification method, a comprehensive review is provided in this paper as an informative source for designers and researchers working in this field.

The purpose of this paper is to examine the toxicological impacts of exhaust generated during the combustion process of aviation fuel containing synthesized hydrocarbons.

Tests on aircraft turbine engines in full scale are complex and expensive. Therefore, a miniature turbojet engine was used in this paper as a source of exhaust gases. Toxicity was tested using innovative BAT–CELL Bio–Ambient Cell method, which consists of determination of real toxic impact of the exhaust gases on the human lung A549 and mouse L929 cells. The research was of a comparative nature. The engine was powered by a conventional jet fuel and a blend of conventional jet fuel with synthesized hydrocarbons.

The results show that the BAT–CELL method allows determination of the real exhaust toxicity during the combustion process in a turbine engine. The addition of a synthetic component to conventional jet fuel affected the reduction of toxicity of exhaust gases. It was confirmed for both tested cell lines.

In the literature related to the area of aviation, numerous publications in the field of testing the emission of exhaust gaseous components, particulates or volatile organic compounds can be found. However, there is a lack of research related to the evaluation of the real exhaust toxicity. In addition, it appears that the data given in aviation sector, mainly related to the emission levels of gaseous exhaust components (CO, Nox and HC) and particulate matters, might be insufficient. To fully describe the engine exhaust emissions, they should be supplemented with additional tests, i.e. in terms of toxicity.