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Describes the parameter estimation procedures for the non‐linear finite element analysis using the hierarchical neural network. These procedures can be classified as the neural network based inverse analysis, which has been investigated by the authors. The optimum values of the parameters involved in the non‐linear finite element analysis are generally dependent on the configuration of the analysis model, the initial condition, the boundary condition, etc., and have been determined in a heuristic manner. The procedures to estimate such multiple parameters consist of the following three steps: a set of training data, which is produced over a number of non‐linear finite element computations, is prepared; a neural network is trained using the data set; the neural network is used as a tool for searching the appropriate values of multiple parameters of the non‐linear finite element analysis. The present procedures were tested for the parameter estimation of the augmented Lagrangian method for the steady‐state incompressible viscous flow analysis and the time step evaluation of the pseudo time‐dependent stress analysis for the incompressible inelastic structure.

The purpose of this paper is to present a simulation‐based evaluation method for the comparison of different organizational forms and software support levels in the field of supply chain management (SCM).

Apart from widely known logistic performance indicators, the discrete event simulation model considers explicitly coordination cost as stemming from iterative administration procedures.

The method is applied to an exemplary supply chain configuration considering various parameter settings. Curiously, additional coordination cost does not always result in improved logistic performance. Influence factor variations lead to different organizational recommendations. The results confirm the high importance of (up to now) disregarded dimensions when evaluating SCM concepts and IT tools.

The model is based on simplified product and network structures. Future research shall include more complex, real world configurations.

The developed method is designed for the identification of improvement potential when SCM software is employed. Coordination schemes based only on ERP systems are valid alternatives in industrial practice because significant investment IT can be avoided. Therefore, the evaluation of these coordination procedures, in particular the cost due to iterations, is of high managerial interest and the method provides a comprehensive tool for strategic IT decision making.

Reviewed literature is mostly focused on the benefits of SCM software implementations. However, ERP system based supply chain coordination is still widespread industrial practice but associated coordination cost has not been addressed by researchers.

An algorithm for simultaneous solution of equations describing transient 3D magnetic field coupled to the Kirchhoff’s equations and the equation of motion has been presented. The nonlinearity and anisotropy of the magnetic core have been taken into account. Numerical implementation of the algorithm is based on the finite element method. In order to solve the 3D problem a special iterative procedure, in which the 3D task is substituted with a sequence of 2D problems, has been proposed. The time‐stepping backward difference algorithm for the time‐discretization of the electric circuit equations has been applied. To determine the moving armature position, an implicit procedure, which is unconditionally stable has been proposed. For the sake of example, the calculations of dynamic operation of the E‐type electromagnetic actuator equipped with the shading coil have been performed.

A fully parallel algorithm for the solution of a finite element system using a MIMD (multiple‐instruction multiple‐data architecture) parallel computer is presented. The formulation includes a simple domain decomposer that automatically divides a finite element mesh into a list of subdomains to guarantee the load balancing. Furthermore, each subdomain is assigned to a processor of a parallel computer and treated as a sub‐finite element system with information exchanged through the interface between two adjacent subdomains. With this new algorithm, these sub‐finite element systems are solved fully parallelly as independent finite element systems, not only the computations of the interior nodes but also the computations of the interface nodes can be executed parallelly. Also, the inherently sequential Gauss‐Seidel and SOR schemes are altered into fully parallel iterative schemes. An implementation of this new scheme on an iPSC/2 D5 Hypercube Concurrent Computer reached an efficiency of more than 100% when compared with the sequential SOR scheme.

The purpose of this paper is to present a new modification of the multimodal pushover method, named the target acceleration method. The target acceleration is the minimum acceleration of the base that leads to the ultimate limit state of the structure, i.e., the lowest seismic resistance.

A nonlinear numerical model is used to determine the target acceleration, which is achieved using the iterative procedure according to the envelope principle. Validation of the target acceleration method was conducted on the basis of the results obtained by incremental dynamic analysis.

The influence of higher modes is highly significant. The general failure vector corresponding to the target acceleration differs from the first load vector and the form of the load with uniform acceleration according to the height of structure, as contained in the European Standard EN 1998-1. Comparison between the target acceleration, including the equivalent structural damping, and the failure peak ground acceleration obtained from the dynamic response of the structure exhibits notably good agreement. This result implies that the equivalent structural damping as calculated according to the formulation presented in this paper should be greater than that suggested in the literature.

The originally developed procedure named multimodal pushover target acceleration method can reasonably estimate the minimum acceleration of the base that leads to the ultimate limit state of the structure, and consequently provides a reliable tool for the assessment of the lowest seismic resistance.

Computer programs were developed based on the finite element method and the charge simulation method for the calculation of three dimensional electric fields in high voltage engineering. A brief description of the applied methods with respect to the special requirements of high voltage engineering is presented. In order to use the specific advantages of the finite element method and the charge simulation method, two procedures combining both methods are proposed: an iterative method and a direct method. For the calculation of three dimensional problems without symmetry the iterative procedure has the advantage that the coupling program is small compared with the field calculation programs and no major changes in these programs are necessary.

Addresses problems in mechanics and physics involving two or more coupled variables of different nature, or a number of distinct domains which interact. For these kinds of problems, considers numerical solution by the coupling of operators appertaining to the individual participating phenomena, or defined in the domains. Reviews the co‐operation of distinct discretized operators in connection with the integration of temporal evolution processes, and the iterative treatment of stationary equations of state. The specification of subtasks complies with the demand for an independent treatment on different processing units arising in parallel computation. Physical subtasks refer to problems of different field variables interacting on the continuum level; their number is usually small. Fine granularity may be achieved by separating the problem region into subdomains which communicate via the boundaries. In multiphysics simulations operators are preferably combined such that subdomains are processed in parallel on different units, while physical phenomena are processed sequentially in the subdomain.

One of the long-standing issues in the field of corporate real estate management is the alignment of an organisation’s real estate to its corporate strategy. To date, 14 models for corporate real estate (CRE) alignment have been made, as well as four comparative studies about CRE alignment. Some of the CRE alignment models indicate that they strive for maximum or optimum added value. However, because most models take a so-called procedural rationality approach, where the focus is not on the content of the decision but on the way that the decision is made, “how a CRE manager can select an (optimum) alternative” stays a black box. The purpose of this paper is to open the black box and offer a Preference-based Accommodation Strategy (PAS) design procedure that enables CRE managers to design a real estate portfolio, makes use of scales for direct measurement of added value/preference, and allows the aggregation of individual ratings into an overall performance rating. This procedure can be used as add-on to existing alignment models.

The objective of this paper is to test if participants are able to successfully perform the PAS procedure in practice. The PAS procedure is in essence a design methodology that aims to solve strategic portfolio design/decision-making problems. In accordance with problem-solving methodology, mathematical models are made for two pilot studies at the Delft University of Technology. This paper describes a second test of the proposed procedure for designing a real estate strategy. The application of real estate strategy design methods in practice is very context-dependent. Applying the PAS procedure to multiple context-dependent cases yields more valuable results than just applying it to one case.

The PAS design procedure enables CRE managers to select the (optimal) solution and thereby enhances CRE decision-making. The pilot study results reveal that, by completing the steps in the PAS procedure, the participants are able to express their preferences accordingly. They designed an alternative portfolio with substantially more added value, i.e. a higher overall preference score, than their current real estate portfolio. In addition, they evaluated the design method positively.

The positive results suggest that designing a strategy by using the PAS design procedure is a suitable approach to alignment.

The PAS design procedure enables CRE managers to determine the added value of a real estate strategy and quickly and iteratively design many alternatives. Moreover, the PAS design method is generic, it can be used for a wide range of real estate portfolio types.

The PAS procedure is original because it considers CRE alignment as a combined design and decision problem. The use of operational design and problem-solving methodologies along with an iterative procedure, instead of empirical/statistical methods and procedures, is a novel approach to CRE alignment. The PAS procedure is tested in a second pilot study to provide an assessment of the methodology through the study by testing it under different conditions to the first study. The novelty of this pilot is also that it allowed testing the procedure in its purest form, as the problem structure did not require the additional use of linear programming.

The purpose of this paper is to apply the conjugate gradient (CG) method, together with the adjoint operator (AO) to the pulsating heat pipe problem, including some quite interesting experimental results. The CG method, together with the AO, was able to estimate the unknown functions more efficiently than the other techniques presented in this paper. The estimation of local heat transfer coefficients, rather than the global ones, in pulsating heat pipes is a relatively new subject and presenting a robust, efficient and self-regularized inverse tool to estimate it, supported also by some experimental results, is the main purpose of this paper. To also increase the visibility and the general use of the paper to the heat transfer community, the authors include, as supplemental material, all numerical and experimental data used in this paper.

The approach was established on the solution of the inverse heat conduction problem in the wall by using as starting data the temperature measurements on the outer surface. The procedure is based on the CG method with AO. The here proposed approach was first verified adopting synthetic data and then it was validated with real cases regarding pulsating heat pipes.

An original fast methodology to estimate local convective heat flux is proposed. The procedure has been validated both numerically and experimentally. The procedure has been compared to other classical methods presenting some peculiar benefits.

The approach is suitable for pulsating heat pipes performance evaluation because these devices present a local heat flux distribution characterized by an important variation both in time and in space as a result of the complex flow patterns that are generated in this type of devices.

The procedure here proposed shows these benefits: it affords a general model of the heat conduction problem that is effortlessly customized for the particular case, it can be applied also to large datasets and it presents reduced computational expense.

An algorithm for domain partitioning with iterative load balancing is presented. A recursive graph labeling scheme is used to distribute elements among subdomains at each iteration. Both graph distance information and information about neighbor vertices are employed during the labeling process. Element quantities for balanced subdomains are predicted, solving the algebraic load balancing problem after each iteration. The same graph labeling scheme with slight modifications is applied to node renumbering inside subdomains. The proposed algorithm is especially suitable for load balancing when a direct method is used for subdomain condensation and the evaluation of cost function is time consuming. Several examples of optimized partitioning of irregular and regular meshes show that load balancing can be achieved with one to three iterations.