THEORETICAL AND EMPIRICAL PROBLEMS IN MODELING OPTIMAL REPLACEMENT OF FARM MACHINES

Farm Management,

Why Have Poorer Neighbourhoods Stagnated Economically, While the Richer have Flourished? Neighbourhood Income Inequality in Canadian Cities

Higher income neighbourhoods in Canada’s eight largest cities flourished economically during the past quarter century, while lower income communities stagnated. This paper identifies some of the underlying processes that led to this outcome. Increasing family income inequality drove much of the rise in neighbourhood inequality. Increased spatial economic segregation, the increasing tendency of “like to live nearby likeâ€, also played a role. In the end, the differential economic outcomes between richer and poorer neighbourhoods originated in the labour market, or in family formation patterns. Changes in investment, pension income, or government transfers played a very minor role. But it was not unemployment that differentiated the richer from poorer neighbourhoods. Rather, it was the type of job found, particularly the annual earnings generated. The end result has been little improvement in economic resources in poor neighbourhoods during a period of substantial economic growth, and a rise in neighbourhood income inequality.Inequality, Neighbourhood, Poverty

Controlling the layer localization of gapless states in bilayer graphene with a gate voltage

Experiments in gated bilayer graphene with stacking domain walls present topological gapless states protected by no-valley mixing. Here we research these states under gate voltages using atomistic models, which allow us to elucidate their origin. We find that the gate potential controls the layer localization of the two states, which switches non-trivially between layers depending on the applied gate voltage magnitude. We also show how these bilayer gapless states arise from bands of single-layer graphene by analyzing the formation of carbon bonds between layers. Based on this analysis we provide a model Hamiltonian with analytical solutions, which explains the layer localization as a function of the ratio between the applied potential and interlayer hopping. Our results open a route for the manipulation of gapless states in electronic devices, analogous to the proposed writing and reading memories in topological insulators