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Riveting deformation is inevitable because of local relatively large material flows and typical compliant parts assembly, which affect the final product dimensional quality and fatigue durability. However, traditional approaches are concentrated on elastic assembly variation simulation and do not consider the impact of local plastic deformation. This paper aims to present a successive calculation model to study the riveting deformation where local deformation is taken into consideration.

Based on the material constitutive model and friction coefficient obtained by experiments, an accurate three-dimensional finite element model was built primarily using ABAQUS and was verified by experiments. A successive calculation model of predicting riveting deformation was implemented by the Python and Matlab and was solved by the ABAQUS. Finally, three configuration experiments were conducted to evaluate the effectiveness of the model.

The model predicting results, obtained from two simple coupons and a wing panel, showed that it was a good compliant with the experimental results, and the riveting sequences had a significant effect on the distribution and magnitude of deformation.

The proposed model of predicting the deformation from riveting process was available in the early design stages, and some efficient suggestions for controlling deformation could be obtained.

A new predicting model of thin-walled sheet metal parts riveting deformation was presented to help the engineers to predict and control the assembly deformation more exactly.

Natural convection in a porous layer between two horizontal, concentric cylinders is investigated numerically by solving the 2‐D Darcy‐Boussinesq equations on a very fine grid. The parabolic‐elliptic system was solved by a second order finite difference scheme based on the implicit alternating direction method coupled with successive under relaxation. The calculations show that for radius ratios above 1.7, the functional relationship between the mean Nusselt number and the Rayleigh number exhibits a closed hysteresis loop associated with the transition from a two to a four cell flow pattern. For very small radius ratios, steady state regimes containing 2, 4, 6, and 8 cells are progressively obtained as the Rayleigh number is increased, but no hysteresis behaviour is observed. For a radius ratio of 2, the numerical results are in good agreement with the experimental data. Multi‐cellular regimes and hysteresis loops have also been reported in the literature for fluid annuli but some differences between the two cases exist and are fully explained below.

Modernisation! That's the thing. New cities, new houses, new factories, new schools, new roads, new ways of doing things: all these are implied by the term modernisation. But above all else modernisation implies new ways of deploying our resources, material and human. Nowhere is this illustrated more graphically than in the modern way in which new roads are planned. Planning and building a motorway is one of the most complex activities of the modern industrial society: it brings together such diverse specialists as town planners, surveyors, lawyers, engineers, politicians and a whole host of highly skilled people of all sorts.

In this paper, methods and algorithms are presented for an efficient slicing process specifically designed for microstereolithography, a high‐resolution rapid prototyping technology. Modifications are given for different implementation environments (FPU, Parallel Computing, directly wired processes). They use the common STL‐format as the description of the 3D objects and compute bitmapped layers for the layered manufacturing step. Specific attention was paid to the requirements for flexibility, accuracy, supporting standards and performance. A layer‐resolution of up to 32767×32767 pixels is supported. The described system is a flexible solution easy to be coupled with almost any system controller for a micro‐stereolithography machine using the integral irradiation process.

The purpose of this paper is to compare torque calculation methods when a non‐conforming movement interface is implemented by means of Lagrange multipliers.

The following methods are here used for computing the torque in a synchronous machine and in a switched reluctance motor: Arkkio's method (AM), local Jacobian matrix derivative (LJD) method, Maxwell stress tensor method (MST) and co‐energy variation method.

This paper shows that, the numerical stability produced by Lagrange multipliers yields a stable torque result, even in thin airgap machines if AM, LJD method or MST method are used.

This work presents a comparative study to indicate the performance of the most commonly used torque calculation methods, when a non‐conforming technique is used, considering a small displacement of the rotor, which is necessary for dynamic cases or coupling with circuit.

The purpose of this paper is to describe the transfer of experiences to improve the basis for overcoming the dilemma of trying to achieve analyses and systems that are both good and simple. The quality of decisions relating to projects depends on how well the assumed basis for the project actually fit the reality of the situation in which the consequences occur. Good value and cost estimations support good decisions about projects insofar as the assumptions on which they are based mirror the reality, and the decision makers can understand the analysis.

The paper uses a longitudinal case study and qualitative analysis. Data relating to a large number of cases have become available to the authors through many years of research and consulting activities. Through joint experience and discussion the patterns are analysed. This paper is descriptive with respect to the challenges and empirical examples. The analysis itself ends with a rather normative conclusion.

There is a dilemma embedded in the processes used to analyse uncertainty and risks associated with projects. On the one hand, an important task is to reduce the complexity of a given situation to render the issues sufficiently simple for them to be understood and assessed. On the other hand, the models and assumptions upon which an analysis is based have to be sufficiently precise and detailed in order to make sense. The same dilemma is found when considering actions to address risks and uncertainties, as well as in designing management systems. It is concluded that the dilemma is real. Solutions have to be found among both good and simple options.

The paper does not answer questions on “how to” and does not dig deep into theoretical perspectives on the current dilemma. More research to understand all aspects of the issue is needed.

Uncertainty analysis and management systems have to be good (precise enough) and at the same time simple (practical). There is no value unless it is used. Practical examples in the paper are intended to help practitioners identify alternative options.

The dilemma of good and simple has not been explicitly addressed before in light of practical experience and theory. The value added is increased awareness of an important problem in analytical processes.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics, and publications of other similar research bodies as issued