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This study aims to investigate the tensile strength and elastic modulus of custom-designed polymer composites developed using voxel-based design. This study also evaluates theoretical models, such as the rule of mixtures, Halpin–Tsai model, Cox–Krenchel model and the Young–Beaumont model and the ability to predict the mechanical properties of particle-reinforced composites based on changes in the design of rigid particles at the microscale within a flexible polymer matrix.

This study leverages the PolyJet process for voxel-printing capabilities and a design of experiments approach to define the microstructural design elements (i.e. aspect ratio, orientation, size and volume fraction) used to create custom-designed composites.

The comparison between the predictions and experimental results helps identify appropriate methods for determining the mechanical properties of custom-designed composites ensuring informed design decisions for improved mechanical properties.

This work centers on multimaterial additive manufacturing leveraging design freedom and material complexity to create a wide range of composite materials. This study highlights the importance of identifying the process, structure and property relationships in material design.

IN the present note a comparison is made between normal aluminium alloys and alloys with increased values of the modulus of elasticity for covering the upper surfaces of wings of moderately thick sections, particularly of the smooth wing type. This comparison is intended to form the basis for the design of test panels for experimental verification of the theoretical conclusions.

This omnibus celebrates the 65th birthday of Professor Dr. Ir Aric van der Neut (and incidentally the premature birth of the Delft University Press from whom a significant aviation book list can be expected in the future). The plan has been for friends and former pupils of the professor from all over the world to contribute papers closely allied to his particular field of engineering science. The objective has certainly been achieved with 26 papers ranging from the theory of multilayer shells by E. I. Grigoliouk and P. P. Chulkov of the Moscow Academy of Sciences to closed form solution to the semi‐infinite cylindrical shell problem by J. L. Sanders of Harvard University and from the subject of buckling of integrally stiffened cylindrical shells by J. Singer of the Israel Institute of Technology to the influence of production imperfections on design of optimum structures by H. L. Cox of the National Physical Laboratory and M. E. Grayley of Engineering Sciences Data Unit. Hardly surprisingly, however, the majority of the papers come from the Netherlands and, perhaps significantly, all except one from universities and institutes rather than people working actually as aircraft constructors.

A method of analysis for determining the transient forced flexural vibrations of accelerating missiles and space vehicles is presented. The equations of motion are in matric form and may be readily adapted to electronic digital computers. The matric formulation for the problem is written to include the effects of engine gimballing resulting from structural coupling of the flight control system, inertial axial loads along the missile, variable stiffness, variable mass, variable mass moment of inertia, variable shear stiffness, structural damping, structurally coupled aerodynamic forces and arbitrary transient forces applied along the missile. Only the basic data for the system are required in the matrices.

The free and harmonically forced flexural vibrations of missiles resting on fixed or mobile launch platforms are considered. A general matric formulation is given for the problem in which the effects of variable boundary conditions at the base support, variable axial loads along the missile length, variable stiffness and material properties, variable mass, variable mass moment of inertia, variable shear stiffness, and variably distributed forcing functions are treated. The problem is matrically formulated in standard eigenvalue form, and no special coding should be required for organizations that are currently solving eigenvalue problems on electronic digital computers. For a particular problem only fundamental data are needed for filling in the element locations of the matrices involved, and almost all calculations are performed within the computer. The matric formulation presented herein is also valid for partially and completely restrained cantilever beams.

This article discusses issues common to the pricing of both insurance and finance. These include increasing collaboration between insurance companies and banks, deregulation of various insurance and finance markets, integrated risk management, and the emergence of financial engineering as a new profession. Rather than attempting to give an exhaustive exposition of the issues at hand, the author highlights developments that, from a methodological point of view, offer new insight into the comparison of pricing mechanisms between insurance and finance.

The free and harmonically forced flexural vibrations of missiles accelerating along initial trajectories are considered. A general matric formulation is given for the problem whereby the effects of variable inertial axial loads along the missile length, variable stiffness and material properties, variable mass, variable mass moment of inertia, variable shear stiffness, and variably distributed forcing functions are treated. The matric formulation of the problem is in standard eigenvalue form and no special coding will be required for organizations that currently are solving eigenvalue problems on electronic digital computers. The time required for an engineer to fill in the matrices of the basic matric equation governing the vibrations of a missile structure is quite small since only fundamental data are needed and almost all calculations are performed within the computer.

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

In strength problems of stresscd‐skin constructions, the outside shape of a part to be stressed as well as the loads sustained by it are generally given. Having this data, the designer or stress analyst in most cases has to choose the type of skin and the best distance between ribs or bulkheads to obtain the lowest weight of construction.

The Council of the Air Registration Board announces the issue of Notice to Licensed Aircraft Engineers and to Owners to Civil Aircraft, No. 10, Issue 4, dated January 1, 1950, which reads as follows: