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Some cycle routes have proved unpopular because at several points a cyclist has to stop or slow very appreciably. Cyclists are discouraged by the resulting extra journey time. Three alternative hypotheses are made for a cyclist's performance in response to an imposed stop. In all he brakes uniformly from a cruising speed. In one, this speed is a personal standard, and he accelerates uniformly to regain it. In the second, because his energy is used in accelerating, he has less to use in cruising. The third hypothesis is that a cyclist's power output in accelerating is the same as in cruising, except at very low speeds, so that he attains his normal cruising speed asymptotically.

Trials were conducted on a lightly trafficked 2.5-km circuit with seven roundabouts. Cyclists made at least two circuits each, one non-stop and one stopping at roundabouts. Pairs of times for each cyclist were compared with derivations from each hypothesis. It was found that the estimates derived from the second hypothesis were much closer to the trial times than those given by the others. The conclusion is that making an adult cyclist stop is equivalent to extending the journey time by as much as an extra 50 m, approximately, would take. In reckoning the lengths of routes in order to select one for development, an equivalent distance of about 50 m should be added for each stop or near stop, unless they are close together.

The paper proposes an efficient and insightful approach for solving neutral delay differential equations (NDDE) with high-frequency inputs. This paper aims to overcome the need to use a very small time step when high frequencies are present. High-frequency signals abound in communication circuits when modulated signals are involved.

The method involves an asymptotic expansion of the solution and each term in the expansion can be determined either from NDDE without oscillatory inputs or recursive equations. Such an approach leads to an efficient algorithm with a performance that improves as the input frequency increases.

An example shall indicate the salient features of the method. Its improved performance shall be shown when the input frequency increases. The example is chosen as it is similar to that in literature concerned with partial element equivalent circuit (PEEC) circuits (Bellen et al., 1999). Its structure shall also be shown to enable insights into the behaviour of the system governed by the differential equation.

The method is novel in its application to NDDE as arises in engineering applications such as those involving PEEC circuits. In addition, the focus of the method is on a technique suitable for high-frequency signals.

The Latin American merger and acquisition (M&A) market offers enormous opportunities. M&A activity in Argentina, Brazil, Chile, Mexico and Venezuela is examined and compared with M&A activity in the United States. Characteristics examined include the industries and form of ownership of the target firms, the types of transactions, and the home countries of the acquiring firms. Differences are found between characteristics of M&A activity in the Latin American countries and the United States. Differences are also found among the characteristics of M&A activity in the various Latin American countries. Implications for managers and areas in need of additional research are discussed.

Describes Childreach – a US child‐focuses development organization which sponsors children and their families in developing countries – and a recent project in development education, “Buffalo banks and borewells: Childreach makes sense of development”, which involved creating and distributing educational newsletters on Third World and development issues. Lists the goals of the project and how they were addressed. Outlines what was gained from the exercise. Links this to the paradoxical situation in the USA whereby the public think money should go towards foreign aid but are reluctant to actually fork out any money themselves. Considers the role of trust and the concept of social capital, emphasizing that sponsors need to trust that their investment is making an important contribution to improving the life of the sponsored child and its family or community.

The purpose of this paper is to carry out a theoretical study of the stability of the mathematical models defined in a class of systems. Furthermore, it will be supposed that the models have been obtained from experimental data and by means of the application of a methodology. The studies carried out in this paper are, on one hand, the theoretical framework for an analysis of the sensitivity and stability of a type of systems; on the other hand, they supplement the studies carried out by the authors, in which, using a computational program, the sensitivity of the mathematical models is analyzed with respect to a type of perturbation.

Initially, a class of systems is considered that are denominated quantifiable systems, in which model systems are defined that are determined by a set and a family of relationships. An initial study of the sensitivity of the mathematical models to perturbations in the experimental data lead to a concept of sensitive and stable models that forms the basis of the theory of stability developed in this paper. Furthermore, this permits a definition of the stability function for the set of the perturbations and, consequently, a determination of stable models according to the defined theoretical structure.

An analysis of the sensitivity and stability of mathematical models in quantifiable systems from a systems theory perspective will be fundamental for the determination of mathematical model stability in environmental systems.

The studies carried out in this paper supposes an advance in the study and modeling of a type of systems that the authors have denominated as quantifiable systems, applicable to the study of environmental systems and supplementing the numeric studies carried out by the authors.

The purpose of this paper is to provide the latest information on mergers and acquisition (M&A) activities in India, Pakistan and Bangladesh from 2000 to 2009.

Using data available from Thomson Financial Service's Worldwide Mergers and Acquisitions database, the paper analyzed M&A transactions listed in the database that were announced between January 1, 2000 and December 31, 2009, in which the target firm or acquirer was located in India, Pakistan or Bangladesh.

M&A in India is a lot more active than that in Pakistan or Bangladesh. One unique feature of Pakistani M&A market is that it has a high ratio (more than 80 percent) for Pakistani firms buying non-Pakistani companies. In Bangladesh, non-Bangladeshi firms acquiring Bangladeshi companies accounted for more than 90 percent of all large M&A value.

The paper provides the latest information on M&A activities in India, Pakistan and Bangladesh from 2000 to 2009. Some similarities and differences among the three countries were compared and discussed.

A balanced armature receiver (BAR) as a special type of electromagnetic acoustic transducers plays a significant role in reproduction of music and speech, active noise control in modern hearing aid and in contemporary in-ear monitors. This paper aims to present a static analysis of the balanced armature receiver based on the lumped network approach (LNA) and the finite element method (FEM).

In this paper, the LNA and two-dimensional FEM are applied to model deflections of the BAR’s armature from the equilibrium position. Results of calculations are compared with measurements.

The derived analytical formulas and developed procedure allow for calculation of the armature deflection.

Comparing to the previous papers, the reluctance’s nonlinearity of the armature has been considered.

The reducing transformation and global optimization technique called Alienor has been developed in the 1980s by Cherruault and Guillez. These methods are based on the approximating properties of α ‐dense curves. The aim of this work is to give a very large class of functions generating α ‐dense curves in a hyper‐rectangle of Rⁿ.

Buffer operators can be utilized to improve the smooth degree of the raw data sequence, and to increase the simulation accuracy of the model. The purpose of this paper is to analyze the cause of increase in the simulation accuracy of the buffer operator.

This paper probed into the modeling mechanism of several typical buffer operators such as the arithmetic buffer operators, the buffer operators with monotonic function and weighted buffer operators. The paper also gives an example of the buffer operator sequence.

The results indicate that after applying an infinite buffer operator, whether the authors adopt a weakening buffer operator or a strengthen buffer operator, the raw sequence can be changed into a constant sequence. Because the discrete GM(1,1) model can completely simulate constant sequence, the simulation accuracy is 100 percent. Because the discrete GM(1,1) model is the accurate form of the GM(1,1) model, after applying an infinite buffer operator, the GM(1,1) model can have a very high simulation accuracy. The buffer operator model can increase the simulation accuracy of both the GM(1,1) model and the discrete GM(1,1) model.

The paper analyses the cause of increasing simulation accuracy of the buffer operator model. The paper may indicate that possible results can be studied in the future. All the buffer operator models have similar properties. After applying an infinite buffer operator, the raw sequence can be changed into a constant sequence. A fixed-point axiom may be the basic cause.

THE use of liquid oxygen as an oxidizer for various fuels in liquid rocket propellent systems is not new. Professor Goddard used liquid oxygen in his rocket experiments and the well known German V‐2 rockets used this material as an oxidizer. However, its effect on non‐metallic materials ordinarily used in rocket systems was not investigated until recent years. This investigation was prompted by phenomena which had been experienced by rocket engine and rocket aircraft manufacturers and by suppliers of the material. It was observed that when some organic materials came in intimate contact with liquid oxygen they became prone to detonation when subjected to certain impact energies. This was undoubtedly due to the formation of unstable organo‐peroxide compounds which when impacted released high levels of energy resulting in an explosion. Specifically, when liquid oxygen was accidently spilled on asphalt and inadvertently stepped on, the asphalt would often explode. Also, leather gaskets immersed in liquid oxygen and subjected to surge impact detonated with disastrous effects.