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Python codes are developed for the versatile structural analysis on a 3 spar multi-cell box beam by means of idealization approach.

Shear flow distribution, stiffener loads, location of shear center and location of geometric center are computed via numpy module. Data visualization is performed by using Matplotlib module.

Python scripts are developed for the structural analysis of multi-cell box beams in lieu of long hand solutions. In-house developed python codes are made available to be used with finite element analysis for verification purposes.

The use of python scripts for the structural analysis provides prompt visualization, especially once dimensional variations are concerned in the frame of aircraft structural design. The developed python scripts would serve as a practical tool that is widely applicable to various multi-cell wing boxes for stiffness purposes. This would be further extended to the structural integrity problems to cover the effect of gaps and/or cut-outs in shear flow distribution in box-beams.

AERONAUTICAL engineers are afflicted by various ‘centres’ which will not stay put. Weights engineers spend much of their time chasing the elusive centre of gravity up and down the fuselage, the aerodynamicist worries about the centre of pressure, and the structural engineer, in addition to these, is cursed with the flexural centre and the shear centre. The main trouble connected with the flexural and shear centre seems to be historical in origin. No real attempt appears to have been made to keep pace with the development of wing structures from the old simple two‐spar, fabric‐covered, constant‐section wing. It is still quite common to see the flexural centre of a wing defined as the point at which a load must be applied, so as to produce bending of the wing without twist. In general, something more precise is required, and, particularly in these days of tapered, swept‐back, stressed‐skin wings, it would seem desirable to review the old definitions and usages of terms such as flexural centre, and flexural axis in order to avoid confusion and possible misstatements or misapplications. The advent of stressed‐skin construction has brought into fairly general use the term shear centre, which is often confused with the flexural centre, although the two points do not necessarily coincide. The use of sweep‐back has caused further confusion concerning the definition of twist. It is hoped that this brief survey may indicate the nature of the confusion that is known to exist—and, perhaps, lead to an authoritative decision, which may standardize terms and definitions.

IN order to obtain a clear view of the analysis it is perhaps better first to consider the analogy of a channel section rigidly attached to two cylinders subjected to a shear at their in the plane of the web of the channel (see Fig. 1).

The purpose of this paper is to present a design sensitivity analysis continuum formulation for the cross-section properties of thin-walled laminated composite beams. These properties are expressed as integrals based on the cross-section geometry, on the warping functions for torsion, on shear bending and shear warping, and on the individual stiffness of the laminates constituting the cross-section.

In order to determine its properties, the cross-section geometry is modeled by quadratic isoparametric finite elements. For design sensitivity calculations, the cross-section is modeled throughout design elements to which the element sensitivity equations correspond. Geometrically, the design elements may coincide with the laminates that constitute the cross-section.

The developed formulation is based on the concept of adjoint system, which suffers a specific adjoint warping for each of the properties depending on warping. The lamina orientation and the laminate thickness are selected as design variables.

The developed formulation can be applied in a unified way to open, closed or hybrid cross-sections.

The purpose of this paper is to get a more consistent finite element description for three-dimensional (3D) Timoshenko beam elements. It extends the common description of beam elements by modifying the shape functions and considers the warping of the cross-section due to torsion.

The paper builds mainly on a finite element description of 3D Timoshenko beam elements. The implementation of high-order shape functions for torsion is done by adding a seventh degree of freedom to the system.

The results reveal that for some beams, depending on their physical dimensions, the warping of the cross-section has large influence. In comparison to a conventional FE program, the extended finite element description considers the warping and yields more accurate results.

An application of the extended finite element description is done with an implementation of the code in MATLAB. The static and dynamic behavior of a rotor in an electrical machine is investigated.

This paper presents a more consistent finite element description of 3D Timoshenko beam elements considering the warping. A comparison to conventional finite element descriptions is given.

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

The purpose of this paper is to see whether the concept of autonomous ship is having an effect on pioneering the sea transportation as well as improvement of ship safety and the possibility of local development. Following the lead of the first autonomous surface ship by Norway that met to develop the Advanced Autonomous Waterborne Application (AAWA) and introduce of autonomous operation to the region, this study also aims to compare the initiation of action by surface ships to that of the air and land vehicle automation.

The ideas for writing this paper came from meeting and interview with maritime professionals such as ship captains, marine chief engineers and naval architects. Through the review of various international journals, the development of Autonomy and Technology are explored and analysed. Owing to the practical approach of this paper, a qualitative research method is used with collecting and analysing information.

The findings of this paper are as follows: it brings out the importance on the potentials of unmanned vessels and its competitive advantages over existing cargo ships. Besides its contribution to reduce fatigue and workload of navigating officers, the improvement of navigational safety by eliminating human errors and reduction of harmful exhaust emission can make shipping safer and more sustainable. However, as the technology is still under development, it is too early for a final evaluation. That said, as the international regulation body, International Maritime Organisation is required to gain acceptance to future unmanned shipping and to designate routes and impose regulations for their safe operation.

Recently, there are many conferences and meetings on autonomous surface vessel focussing on regulation, technology, human-factor, legal and regulatory framework for such ships around the world. This paper summarises the current development of the autonomous surface ships, in term of the design and technology, their interaction and co-existence with manned ships and suggest some operation issues on board an autonomous surface ship during voyage. Taking Hong Kong as an example, this paper attempts to examine the feasibility for introducing the autonomous surface ships in local waters.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.

Crime is becoming ever more international. This is a world where it is quicker to cross the Atlantic from Paris to New York than to traverse the city of Paris by road. This world is faced with a criminality that profits by the advantages of the so‐called free world, where there are practically no frontiers any more. Whether it is drug trafficking, financial fraud or cyber‐pornography, crime has gone global on a massive scale as borders fade and cash rockets from Grand Cayman to Hong Kong, Luxembourg or Vanuatu in the flash of a second. Criminals know no geographical boundaries; nor does their dirty money recognise any such barriers.