Comment on: Weak Anisotropy and Disorder Dependence of the In-Plane Magnetoresistance in High-Mobility (100) Si Inversion Layers

Comment on: Weak Anisotropy and Disorder Dependence of the In-Plane Magnetoresistance in High-Mobility (100) Si Inversion LayersComment: 1 page, submitted to PR

TDRSS telecommunications system, PN code analysis

The pseudo noise (PN) codes required to support the TDRSS telecommunications services are analyzed and the impact of alternate coding techniques on the user transponder equipment, the TDRSS equipment, and all factors that contribute to the acquisition and performance of these telecommunication services is assessed. Possible alternatives to the currently proposed hybrid FH/direct sequence acquisition procedures are considered and compared relative to acquisition time, implementation complexity, operational reliability, and cost. The hybrid FH/direct sequence technique is analyzed and rejected in favor of a recommended approach which minimizes acquisition time and user transponder complexity while maximizing probability of acquisition and overall link reliability

What image features guide lightness perception?

Lightness constancy is the ability to perceive black and white surface colors under a wide range of lighting conditions. This fundamental visual ability is not well understood, and current theories differ greatly on what image features are important for lightness perception. Here we measured classification images for human observers and four models of lightness perception to determine which image regions influenced lightness judgments. The models were a high-pass-filter model, an oriented difference-of-Gaussians model, an anchoring model, and an atmospheric-link-function model. Human and model observers viewed three variants of the argyle illusion (Adelson, 1993) and judged which of two test patches appeared lighter. Classification images showed that human lightness judgments were based on local, anisotropic stimulus regions that were bounded by regions of uniform lighting. The atmospheric-link-function and anchoring models predicted the lightness illusion perceived by human observers, but the high-pass-filter and oriented-difference-of-Gaussians models did not. Furthermore, all four models produced classification images that were qualitatively different from those of human observers, meaning that the model lightness judgments were guided by different image regions than human lightness judgments. These experiments provide a new test of models of lightness perception, and show that human observers' lightness computations can be highly local, as in low-level models, and nevertheless depend strongly on lighting boundaries, as suggested by midlevel models.York University Librarie

POTENTIAL WATER USE CONFLICTS GENERATED BY IRRIGATED AGRICULTURE IN RHODE ISLAND

This study constructs a simulation model to evaluate the potential for conflict among residential and agricultural users of water in southern Rhode Island. The model estimates the profitability of irrigation and turf farms and projects the total use and the economic value of irrigation water. The results indicate that the economic value of irrigation water compares favorably with current residential water prices in the area. In addition, substantial demand for irrigation water is projected. Given current rates of growth in turf acreage and residential water use, there appears to be a significant potential for conflict, particularly given the absence of well developed institutions for allocating water among users.Resource /Energy Economics and Policy,

Magnetoresistance of a two-dimensional electron gas in a parallel magnetic field

The conductivity of a two-dimensional electron gas in a parallel magnetic field is calculated. We take into account the magnetic field induced spin-splitting, which changes the density of states, the Fermi momentum and the screening behavior of the electron gas. For impurity scattering we predict a positive magnetoresistance for low electron density and a negative magnetoresistance for high electron density. The theory is in qualitative agreement with recent experimental results found for Si inversion layers and Si quantum wells.Comment: 4 pages, figures included, PDF onl

A randomized controlled pilot trial of classroom-based mindfulness meditation compared to an active control condition in sixth-grade children

The current study is a pilot trial to examine the effects of a nonelective, classroom-based, teacher-implemented, mindfulness meditation intervention on standard clinical measures of mental health and affect in middle school children. A total of 101 healthy sixth-grade students (55 boys, 46 girls) were randomized to either an Asian history course with daily mindfulness meditation practice (intervention group) or an African history course with a matched experiential activity (active control group). Self-reported measures included the Youth Self Report (YSR), a modified Spielberger State-Trait Anxiety Inventory, and the Cognitive and Affective Mindfulness Measure –Revised. Both groups decreased significantly on clinical syndrome subscales and affect but did not differ in the extent of their improvements. Meditators were significantly less likely to develop suicidal ideation or thoughts of self-harm than controls. These results suggest that mindfulness training may yield both unique and non-specific benefits that are shared by other novel activities

The Cochlear Tuning Curve

The tuning curve of the cochlea measures how large an input is required to elicit a given output level as a function of the frequency. It is a fundamental object of auditory theory, for it summarizes how to infer what a sound was on the basis of the cochlear output. A simple model is presented showing that only two elements are sufficient for establishing the cochlear tuning curve: a broadly tuned traveling wave, moving unidirectionally from high to low frequencies, and a set of mechanosensors poised at the threshold of an oscillatory (Hopf) instability. These two components suffice to generate the various frequency-response regimes which are needed for a cochlear tuning curve with a high slope

In Honor of Walter O. Weyrauch: Substantive Due Process Limits on Punitive Damages Awards: Morals Without Technique ?

In a series of cases decided over the last two decades, the Supreme Court has used the Due Process Clause to establish a procedural and substantive framework for awarding punitive damages. Initially, the substantive aspects of this framework were sufficiently clear and flexible that they required little change in the system and probably generated a helpful level of debate and uniformity as to some basic requirements for awards. However, in BMW of North America, Inc. v. Gore, the Court adopted an approach characterized by a lack of clarity and consistency, an inadequate basis in theory and policy, and ad hoc decisions. The harmful results of this approach are evident in the Court’s recent decision, Philip Morris USA v. Williams, which requires states to instruct juries in terms of a distinction that the four dissenting judges refer to as elusive, unclear, and confusing. Even if one accepts the view that there should be, at some point, substantive due process limits on the amount of punitive damages, decisions like Williams are likely to make the process less fair and reliable. Therefore, the Court should abandon its current approach, which is both unnecessary and likely to do more harm than good, and should, instead, be more deferential to the state courts and legislatures, and be more concerned with developing a coherent framework