The impact of climate change on ski resort operations and development : opportunities and threats

Thesis (S.M. in Real Estate Development)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections."September 2007."Includes bibliographical references (leaves 54-58).This thesis serves as a pedagogical guide to the ski resort industry, and presents a broad overview of the unique issues that accompany climate change. The paper also provides recommendations to resort developers as to which regions of North America will likely become desirable destination for skiers in light of such changes. The ski resort industry is on the cutting edge with respect to sustainable building techniques and adoption of innovative "green" principles in day-to-day operations. But while these efforts are admirable and set an important precedent, in the global context they do little to stem the tide of global warming which penalizes indiscriminately. It is therefore necessary for stakeholders within the ski industry to not only embrace adoption strategies, but also to consider what preemptive actions can be taken to capitalize on global warming. Using historical annual total snowfall records and "skier visit" data, this study intends to quantify the extent to which climate change has impacted resort operations in different regions of the United States over the last several decades. In addition, the paper provides an overview of current and future effects of climate change on North America's ski resort industry and provides recommendations as to how these operators can adapt to ever changing conditions over the next 30 - 50 years. This is followed by a review of climate adaptation practices currently employed by resort operators and stakeholders. With few exceptions, existing literature on this topic has neglected to consider what opportunities might emerge as a result of climate change. While the field of climatology is an ever evolving science, the ski industry would be wise to take note as global warming is likely to prove one of those tectonic forces that gradually - but powerfully - changes the economic landscape in which they operate.by Daniel D.D. McGill.S.M.in Real Estate Developmen

Relativistic three-body bound states and the reduction from four to three dimensions

Beginning with an effective field theory based upon meson exchange, the Bethe-Salpeter equation for the three-particle propagator (six-point function) is obtained. Using the one-boson-exchange form of the kernel, this equation is then analyzed using time-ordered perturbation theory, and a three-dimensional equation for the propagator is developed. The propagator consists of a pre-factor in which the relative energies are fixed by the initial state of the particles, an intermediate part in which only global propagation of the particles occurs, and a post-factor in which relative energies are fixed by the final state of the particles. The pre- and post-factors are necessary in order to account for the transition from states where particles are off their mass shell to states described by the global propagator with all of the particle energies on shell. The pole structure of the intermediate part of the propagator is used to determine the equation for the three-body bound state: a Schr{\"o}dinger-like relativistic equation with a single, global Green's function. The role of the pre- and post-factors in the relativistic dynamics is to incorporate the poles of the breakup channels in the initial and final states. The derivation of this equation by integrating over the relative times rather than via a constraint on relative momenta allows the inclusion of retardation and dynamical boost corrections without introducing unphysical singularities.Comment: REVTeX, 21 pages, 4 figures, epsf.st

Electrophysiological activation by masked primes: Independence of prime-related and target-related activities

Visual stimuli that are made invisible by metacontrast masking (primes) have a marked influence on behavioral and psychophysiological measures such as reaction time (RT) and the lateralized readiness potential (LRP). 4 experiments are reported that shed light on the effects that masked primes have on the LRP. Participants had a go-nogo task in which the prime was associated with 1 of 2 responses even if the target required participants to refrain from responding. To analyze the electrophysiological responses, we computed the LRP and applied an averaging method separating the activation due to the prime and the target. The results demonstrated that (a) masked primes activate responses even in a nogo situation, (b) this prime-related activation is independent of masking, (c) and is also independent of whether prime and target require the same responses (congruent condition) or different responses (incongruent condition)

Rationality and the experimental study of reasoning

A survey of the results obtained during the past three decades in some of the most widely used tasks and paradigms in the experimental study of reasoning is presented. It is shown that, at first sight, human performance suffers from serious shortcomings. However, after the problems of communication between experimenter and subject are taken into account, which leads to clarify the subject's representation of the tasks, one observes a better performance, although still far from perfect. Current theories of reasoning, of which the two most prominent are very briefly outlined, agree in identifying the load in working memory as the main source of limitation in performance. Finally, a recent view on human rationality prompted by the foregoing results is described

AGL StimSelect: Software for automated selection of stimuli for artificial grammar learning

Artificial Grammar Learning (AGL) is an experimental paradigm that has been used extensively in cognitive research for many years to study implicit learning, associative learning, and generalization based either on similarity or rules. Without computer assistance it is virtually impossible to generate appropriate grammatical training stimuli along with grammatical or non-grammatical test stimuli that control relevant psychological variables. We present the first flexible, fully automated software for selecting AGL stimuli. The software allows users to specify a grammar of interest, and to manipulate characteristics of training and test sequences, and their relationship to each other. The user thus has direct control over stimulus features that may influence learning and generalization in AGL tasks. The software enables researchers to develop AGL designs that would not be feasible without automatic stimulus selection. It is implemented in Matlab