For most of the twentieth century, collective bargaining provided the terms on which labour was commonly employed in Britain. However, the quarter century since 1980 has seen the collapse of collectivism as the main way of regulating employment. Our argument is that the tacit settlement between organized labour and employers was undermined by increasing product market competition. The paper fir...

The distribution of intertidal organisms can often be determined by processes operating at the time of recruitment. Recruitment has been demonstrated to influence the composition of assemblages of natural habitats, but there is less evidence of its importance in artificial habitats. Coastal areas are becoming increasingly urbanised, with the replacement of many natural habitats by man-made stru...

The single vehicle routing problem with multiple routes is a variant of the vehicle routing problem where the vehicle can be dispatched to several routes during its workday to serve a number of customers. In this paper we propose a goal programming model for multi-objective single vehicle routing problem with time windows and multiple routes. To solve the model, we present a heuristic method wh...

Chaos based communications have drawn increasing attention over the past years. Chaotic signals are derived from non-linear dynamic systems. They are aperiodic, broadband and deterministic signals that appear random in the time domain. Because of these properties, chaotic signals have been proposed to generate spreading sequences for wide-band secure communication recently. Like conventional DS...

Chaos is exhibited in the diode resonator circuit due to the unrecombined charges that cross the p-n junction when the diode is in the forward bias mode. When the diode switches biases, the charges diffuse back to their original plate making the diode act as a capacitor. The larger the forward current, the greater the amount of charges that cross the junction and the longer the system will need...

The bifurcation diagram of a truncation to six degrees of freedom of the equations for quasi-geostrophic, baroclinic ow is investigated. Period doubling cascades and Shil'nikov bifurcations lead to chaos in this model. The low dimension of the chaotic attractor suggests the possibility to reduce the model to three degrees of freedom. In a physically comprehensible limit of the parameters this r...

The bifurcation structure of coupled periodically driven double-well Duffing oscillators is investigated as a function of the strength of the driving force f and its frequency Ω. We first examine the stability of the steady state in linear response, and classify the different types of bifurcation likely to occur in this model. We then explore the complex behaviour associated with these bifurcat...

The response of an excitable neuron to trains of electrical spikes is relevant to the understanding of the neural code. In this paper, we study a neurobiologically motivated relaxation oscillator, with appropriately identified fast and slow coordinates, that admits an explicit mathematical analysis. An application of geometric singular perturbation theory shows the existence of an attracting in...

Chaos is the likely outcome of the interaction between a parasite and a host with discrete generations, if the parasite's virulence is high and if transmission from one generation to the next is held constant. We studied two alternative routes of transmission-vertical transmission from infecteds to their offspring, and transmission via long-lasting spores produced in those individuals that were...

The bifurcation diagram of a truncation to six degrees of freedom of the equations for quasi-geostrophic, baroclinic flow is investigated. Period doubling cascades and Shil’nikov bifurcations lead to chaos in this model. The low dimension of the chaotic attractor suggests the possibility to reduce the model to three degrees of freedom. In a physically comprehensible limit of the parameters this...