University of Maine

About: University of Maine is a education organization based out in Orono, Maine, United States. It is known for research contribution in the topics: Population & Ice sheet. The organization has 8637 authors who have published 16932 publications receiving 590124 citations. The organization is also known as: University of Maine at Orono.

The Effect of Agricultural Policies on Land Use and Environmental Quality

Abstract: In this paper I consider the environmental quality gains that may be achieved by reducing agricultural income supports. A new methodology is developed to estimate land use shares. In an application to Wisconsin, milk price support reductions result in shifts of marginal agricultural land to forest, reducing soil erosion and providing off-site water quality improvements. The environmental benefits are estimated to be at least as large as the decreased welfare burden on consumers and taxpayers, indicating a central role for environmental quality considerations in motivating policy reforms and a more efficient means of achieving the environmental quality goals of land retirement programs.

Parallel evolution of the sexes? Effects of predation and habitat features on the size and shape of wild guppies.

Abstract: Environmental gradients often lead to the parallel evolution of populations and species. To what extent do such gradients also lead to parallel evolution of the sexes? We used guppies (Poecilia reticulata) to examine the parallel and independent (sex-specific) aspects of population divergence in response to predation and habitat features. Geometric morphometrics was used to analyse size and shape variation for 1335 guppies from 27 to 31 sites sampled in each of 2 years. Body size showed strong parallel population divergence; both sexes were larger at sites with a more open canopy and with higher flow. Body shape showed a mixture of parallel and independent population divergence. The strongest and most consistent effects were (1) high-predation sites had males with smaller heads and deeper caudal peduncles, (2) open-canopy sites had females with smaller heads and more distended abdomens and (3) high-flow sites had males and females with smaller heads and deeper caudal peduncles.

Recent advances on TiO2-based photocatalysts toward the degradation of pesticides and major organic pollutants from water bodies

Abstract: Pesticides and organic waste constitute a group of environmental pollutants that are widely distributed in our environment due to various human activities. Adsorptive removal and photocatal...

Effect of skew, pole count and slot count on brushless motor radial force, cogging torque and back EMF

Abstract: Permanent magnet brushless motors are increasingly being used in high performance applications. In many of these applications, the acoustic noise and torque ripple characteristics of the motor are of primary concern. Because of this concern, it is important to understand the influence of the motor geometrical parameters of skew amount, pole count and slot count on the resulting motor characteristics of radial force, cogging torque and back EMF. While these relationships are understood intuitively and have been explored experimentally and predicted numerically, they have not been confirmed analytically for motors having any combination of skew amount, pole count and slot count. The paper fills this void by exploring these relationships analytically using a Fourier series. The influence of skew amount, pole count and slot count on motor radial force, cogging torque and back EMF are shown to confirm prior experimental and numerical results. More importantly, the derived analytical results provide valuable insight into the implications of common motor design choices.