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The purpose of this paper is to solve unsteady compressible Navier–Stokes equations without the commonly used dual-time loop. The authors would like to use an adaptive time-stepping (ATS)-based local error control instead of CFL-based time-stepping technique. Also, an all-speed flow algorithm is implemented with simple low dissipation AUSM convective scheme, which can be computed without preconditioning which in general destroys the time accuracy.

In transient flow computations, the time-step is generally determined from the CFL condition. In this paper, the authors demonstrate the usefulness of ATS based on local time-stepping previously used extensively in ordinary differential equations (ODE) integration. This method is implemented in an implicit framework to ensure the numerical domain of dependence always contains the physical domain of dependence.

In this paper, the authors limit their focus to capture the unsteady physics for three cases: Sod’s shock-tube problem, Stokes’ second problem and a circular cylinder. The use of ATS with local truncation error control enables the solver to use the maximum allowable time-step, for the prescribed tolerance of error. The algorithm is also capable of converging very rapidly to the steady state (if there is any) after the initial transient phase. The authors present here only the first-order time-stepping scheme. An algorithmic comparison is made between the proposed adaptive time-stepping method and the commonly used dual time-stepping approach that indicates the former will be more efficient.

The original method of ATS based on local error control is used extensively in ODE integration, whereas, this method is not so popular in the computational fluid dynamics (CFD) community. In this paper, the authors investigate its use in the unsteady CFD computations. The authors hope that it would provide CFD researchers with an algorithm based on an adaptive time-stepping approach for unsteady calculations.

This paper aims to present a finite element formulation to approximate systems of reaction–diffusion–advection equations, focusing on cases with nonlinear reaction. The formulation is based on the orthogonal sub-grid scale approach, with some simplifications that allow one to stabilize only the convective term, which is the source of potential instabilities. The space approximation is combined with finite difference time integration and a Newton–Raphson linearization of the reactive term. Some numerical examples show the accuracy of the resulting formulation. Applications using classical nonlinear reaction models in population dynamics are also provided, showing the robustness of the approach proposed.

A stabilized finite element method for advection–diffusion–reaction equations to the problem on nonlinear reaction is adapted. The formulation designed has been implemented in a computer code. Numerical examples are run to show the accuracy and robustness of the formulation.

The stabilized finite element method from which the authors depart can be adapted to problems with nonlinear reaction. The resulting method is very robust and accurate. The framework developed is applicable to several problems of interest by themselves, such as the predator–prey model.

A stabilized finite element method to problems with nonlinear reaction has been extended. Original contributions are the design of the stabilization parameters and the linearization of the problem. The application examples, apart from demonstrating the validity of the numerical model, help to get insight in the system of nonlinear equations being solved.

“Since films attract an audience of millions, the need and appetite for information about them is enormous.” So said Harold Leonard in his introduction to The Film Index published in 1941. The 1970's has produced more than enough — too much — food to satisfy that appetite. In the past five years the number of reference books, in this context defined as encyclopedias, handbooks, directories, dictionaries, indexes and bibliographies, and the astounding number of volumes on individual directors, complete histories, genre history and analysis, published screenplays, critics' anthologies, biographies of actors and actresses, film theory, film technique and production and nostalgia, that have been published is overwhelming. The problem in film scholarship is not too little material but the senseless duplication of materials that already exist and the embarrassing output of items that are poorly or haphazardly researched, or perhaps should not have been written at all.

The main purpose of this paper is to highlight the significance of TAM factors in the light of some external factors on students' e‐retention and the mediating role of e‐satisfaction within United Arab Emirates (UAE) e‐learning context.

The relative importance of TAM factors was examined, as well as enjoyment and blackboard design on students' e‐satisfaction and e‐retention. The survey was designed and administrated using face‐to‐face method. Data were collected from a convenient sample of students who use blackboard system. AMOS 6 was used to test for the hypothesized relationships.

Perceived usefulness has a direct and positive relationship with students' e‐satisfaction and e‐retention while perceived ease of use has only a direct relationship with students' e‐retention. Design features and enjoyment have only a significant relationship with students' e‐satisfaction without any direct relationship with students' e‐retention. Finally, students' e‐satisfaction has a direct relationship with students' e‐retention.

This research has only surveyed students from one university in UAE. Further testing of the proposed conceptual model across different industries and countries is needed to determine the generalisability and consistency of this study's findings.

The proposed model of students' e‐retention prediction has the potential to help UAE university managers to understand some of the factors influencing students' behaviours and attitudes toward e‐learning systems. This will lead to improving the education quality within the context of UAE.

This paper is a significant trial in how TAM factors and other external factors might influence students' e‐satisfaction and e‐retention within UAE e‐learning context.

Describes some of the successful innovations to be seen at Unishoe (Universal Shoe Machine Company Limited), such as a fully automated sole preparation line; a stress reliever lamp for removing creases from shoe uppers; machines for fitting metal shanks to the “shankboards” for stiffening insoles; and machines for conditioning and lasting uppers into shape.

The factors which influence costs of production of food and the prices to the consumer have changed dramatically during this century, but especially since the establishment of trading systems all over the world. Gone are the days when the simple expedients of supply and demand alone governed the situation. The erosion of these principles began at the turn of the century, mainly as a result of the introduction by the rapidly developing industrial power of the USA to protect her own industries against the cheaper products of European countries. They introduced the system of tariffs on imported manufactured goods; it grew and eventually was made to apply to wide sectors of industry. European countries retaliated but the free trade policy of Britain's Liberal government was making the country a dumping ground for all other country's cheap products and surpluses.

Purpose — Analysis of nonprismatic members has received a great deal attention from designers and engineers due to their ability in satisfaction of architectural and aesthetic necessities. Using these structural members in complex structures such as aircrafts, turbine blades and space vehicles, exact static and dynamic analyses of these members become more significant. Based on structural/mechanical principles, the purpose of this paper is to present a new method to evaluate exact structural matrices for nonprismatic Euler‐Bernoulli beam elements. Design/methodology/approach — Through introducing the concept of basic displacement functions (BDFs), it is shown that exact shape functions are derived in terms of BDFs. BDFs and their derivatives have structural interpretations; therefore, they are obtained via application of flexibility method. Unlike the conventional methods, which are almost categorized as displacement‐based methods, the flexibility basis of the method ensures the true satisfaction of equilibrium equations at any interior point of the element. Findings — The exact shape functions and consequently structural matrices are derived for general nonprismatic beam elements. Numerical examples are carried out to determine static deflection and natural frequencies, and the results are highly competent with the other methods in literature. Research limitations/implications — The method can be extended to structural analysis of curved beams, plates and shells as well. Moreover, it is possible to derive exact dynamic shape functions via BDFs by solving the governing equation for transverse vibration of beams. Theoretically, the method faces limitation in analysis of nonprismatic beams that converge to a point where cross‐sectional area and moment of inertia are equal to zero. Practical implications — The development of this idea, i.e. BDFs seems to lead to promotive novel approaches for structural analysis and could be a breaking point for developing new elements for plates and shells as it was shown for beam elements. Originality/value — The paper's introduction of special functions, namely BDFs and their application, in both static and dynamic analyses of structures, could be a breaking point in analysis procedures.

Proposes a system in which the information superhighway can be built, maintained and routinely upgraded by the efforts of multitudes of small scale servers looking after only their own individual economic interests. Each server will be classified as either a “parasitic” server or an “integrated” server. At a given band‐width level, integrated servers are equal to each other in their network, but parasitic servers will be functionally dependent on their integrated parent servers to which they must pay a fee. Although it is initially cheaper to open a parasitic server, economic incentive will motivate owners of parasitic servers to make their servers integrated. The primeval seed of this network will be a structure composed of three servers arranged in a triangle called the “base delta.” The first integrated servers will be connected to each of the three base delta servers. Later, servers will have to be connected to at least three other integrated servers to qualify as integrated servers. Each base delta will have a territory extending from it that, when intermeshed with other base delta territories, will become “integrated” base delta territories. All integrated servers within integrated base delta territories are equal to each other in function. The aim is to motivate the owners of independent small‐scale servers in such a way as to cover the globe with integrated base delta territories.