Kuantan River, Malaysia: Prediction of salinity intrusion

A mathematical model was used to simulate the long-term movements of the high water slack longitudinal salinity profile in the estuary of the Sg Kuantan, Malaysia. The proven model was then used to predict the effects on salinity of increased abstractions from the estuary under various drought conditions. The predicted longitudinal profiles were...

Worst case gust shapes for atmospheric turbulence with known spectrum

A worst case gust shape has been derived for turbulence or gust patches, assuming only that the average spectrum of such patches is known. The maximum value of the response can be calculated quite easily. The result differs from the PSD-method. Some examples of worst case inputs and outputs are given, also for nonlinear systems.

Axisymmetric liquid sloshing under low-g conditions: numerical simulations method (-reference manual-)

A mathematical model is presented for the description of axisymmetric three-dimensional transient flow of a viscous liquid in a partially filled cylindrical container under low gravity conditions. The mathematical model consists of the Navier-Stokes equations with either no-slip condition at the solid boundaries, and with the continuity of...

Contribution to the Theory of Internal Waves

The behaviour of internal waves in vertically inhomogeneous fluids has been studied theoretically by various authors, from the point of view of general hydrodynamics as well as of meteorology and of physical oceanography (see the list of references, which, however, is not meant to be complete). For mathematical reasons most of them assumed...

PROCRU simulation results compared with Metro II in-flight ILS approach data

The PROCRU (Procedure Oriented Crew) model has been developed for the analysis and modeling of flight crew procedures during an ILS approach. The model's specific capability concerns the generation of "timelines" of the necessary actions to be carried out by each crew member during the approach. Besides, also the corresponding timelines for...

The response of aircraft to two-dimensional vertical turbulence

Equations for the response of an aircraft to two-dimensional vertical atmospheric turbulence have been derived, both for an aircraft regarded as a continuous system and for an aircraft split up into a number of panels. These equations have been applied to an aircraft model with two degrees of freedom of the size of the Fokker 100, respectively....

TULIPS: A method to calculate transonic potentional flow about oscillating airfoils

A description is given of TULIPS - a method for Transonic Unsteady Lifting Inviscid Potential-flow Simulation. The Mathematical formulation and the numerical approach are presented for flow about oscillating airfoils. TULIPS is based on the numerical integration of the unsteady full-potential equation in generalized coordinates. The equation is...

One-dimensional analysis of salinity intrusion in estuaries

This report describes a mathematical model that was developed to predict salinity intrusion in estuaries as it is affected by control and abstraction of fresh water. The need for such a model, particularly for estuaries in tropical areas with large variations in fresh water flow, capable of giving satisfactory predictions of salinity movement...

Modelling of Environmental Ageing of Polymers and Polymer Composites—Modular and Multiscale Methods

Service lifetimes of polymers and polymer composites are impacted by environmental ageing. The validation of new composites and their environmental durability involves costly testing programs, thus calling for more affordable and safe alternatives, and modelling is seen as such an alternative. The state-of-the-art models are systematized in...

Multiscale models driving hypothesis and theory-based research in microbial ecology

Hypothesis and theory-based studies in microbial ecology have been neglected in favour of those that are descriptive and aim for data-gathering of uncultured microbial species. This tendency limits our capacity to create new mechanistic explanations of microbial community dynamics, hampering the improvement of current environmental...

Electromagnetism in the Electrical Engineering Classroom: Dominant trends in teaching classical electromagnetic field theory and innovation vectors

This article explores some dominant trends in teaching classical electromagnetic (EM) field theory in electrical engineering (EE) undergraduate curricula. The acronym EM will be used interchangeably to designate either electromagnetic or electromagnetism. The intended significance will be evident from the context.