The Three Loop Isotopy and Framed Isotopy Invariants of Virtual Knots

This paper introduces two virtual knot theory ``analogues'' of a well-known family of invariants for knots in thickened surfaces: the Grishanov-Vassiliev finite-type invariants of order two. The first, called the three loop isotopy invariant, is an invariant of virtual knots while the second, called the three loop framed isotopy invariant, is a regular isotopy invariant of framed virtual knots. The properties of these invariants are investigated at length. In addition, we make precise the informal notion of ``analogue''. Using this formal definition, it is proved that a generalized three loop invariant is a virtual knot theory analogue of a generalization of the Grishanov-Vassiliev invariants of order two

Using IMPRINT to Guide Experimental Design with Simulated Task Environments

Experimental Designs involving Simulated Task Environments aim to explore interesting conditions with human subjects. By using activity simulators such as IMPRINT, it may be possible to identify these conditions of interest without the need for human subjects. This thesis presents research that aims to demonstrate that IMPRINT can be used to predict human performance in a task environment representing the task performed by Network Analysts of the 33rd Network Warfare Squadron. The research is done by examining the task performed by the Network Analysts, and then designing a Simulated Task Environment modeled on this task. A model of the task performed is also built in IMPRINT. With a first iteration, it was found that the IMPRINT model was not able to predict performance in a majority of cases, however the methodology illustrates a starting point that others may use

Annual Aboveground Biomass Growth in Temperate Forests of Eastern North America

The below dissertation is organized into three individual standalone manuscripts supporting the overarching theme of reconstructing annual aboveground biomass growth in temperate forests of eastern North America using dendrochronological applications. Each manuscript is organized with the intent of submission to a peer-reviewed journal. The first manuscript validated the technique I use throughout my dissertation by comparing tree-ring derived estimates of annual aboveground productivity with estimates from co-located or nearby permanent remeasurement plots at Howland, Maine, Harvard Forest, Massachusetts, and Fernow, West Virginia. The second manuscript investigated the size-related distribution of biomass growth at 16 eastern U.S. forest sites and compared results with United States Forest Service inventory plot data. The goal of this manuscript was to determine where, structurally, biomass was allocated in forests and whether these quantities changed over time and between forests. The third manuscript was inspired by the results of my second chapter. Here, I investigated whether the degree of asymmetry, or the slope of the linear regression between tree diameter and growth, is a useful indicator of total forest productivity. Previous studies linking asymmetry and productivity have been inconclusive, and this chapter evaluates consistency or lack of consistency across the same 16-site eastern U.S. forest network

Predicting the Impact of Climate Change on Threatened Species in UK Waters

Global climate change is affecting the distribution of marine species and is thought to represent a threat to biodiversity. Previous studies project expansion of species range for some species and local extinction elsewhere under climate change. Such range shifts raise concern for species whose long-term persistence is already threatened by other human disturbances such as fishing. However, few studies have attempted to assess the effects of future climate change on threatened vertebrate marine species using a multi-model approach. There has also been a recent surge of interest in climate change impacts on protected areas. This study applies three species distribution models and two sets of climate model projections to explore the potential impacts of climate change on marine species by 2050. A set of species in the North Sea, including seven threatened and ten major commercial species were used as a case study. Changes in habitat suitability in selected candidate protected areas around the UK under future climatic scenarios were assessed for these species. Moreover, change in the degree of overlap between commercial and threatened species ranges was calculated as a proxy of the potential threat posed by overfishing through bycatch. The ensemble projections suggest northward shifts in species at an average rate of 27 km per decade, resulting in small average changes in range overlap between threatened and commercially exploited species. Furthermore, the adverse consequences of climate change on the habitat suitability of protected areas were projected to be small. Although the models show large variation in the predicted consequences of climate change, the multi-model approach helps identify the potential risk of increased exposure to human stressors of critically endangered species such as common skate (Dipturus batis) and angelshark (Squatina squatina)

New Measurable Indicator for Tuberculosis Case Detection

Conducting prevalence surveys at 5- to 10-year intervals would allow countries to determine their case detection performance

Geo-neutrinos and Earth Models

We present the current status of geo-neutrino measurements and their implications for radiogenic heating in the mantle. Earth models predict different levels of radiogenic heating and, therefore, different geo-neutrino fluxes from the mantle. Seismic tomography reveals features in the deep mantle possibly correlated with radiogenic heating and causing spatial variations in the mantle geo-neutrino flux at the Earth surface. An ocean-based observatory offers the greatest sensitivity to the mantle flux and potential for resolving Earth models and mantle features. Refinements to estimates of the geo-neutrino flux from continental crust reduce uncertainty in measurements of the mantle flux, especially measurements from land-based observatories. These refinements enable the resolution of Earth models using the combined measurements from multiple continental observatories.Comment: 9 pages, 4 figures; Contributed paper TAUP 201

Results of phase change paint tests of 0.040 scale 50% forebody models (82-0) of the space shuttle orbiter in the AEDC VKF B hypersonic wind tunnel (OH75)

Post-test information and data are presented from phase change paint, aerodynamic heating wind tunnel tests of a Rockwell International space shuttle orbiter forebody model. These tests were conducted in the Arnold Engineering and Development Center von Karman Facility Tunnel B Hypersonic Wind Tunnel. The purpose of these tests was to determine the effect of simulated orbiter protuberances and penetrations (including RCS nozzles) on aerodynamic heating rates during simulated entry conditions

Heat transfer phase change paint tests of 0.0175-scale models (nos. 21-0 and 46-0) of the Rockwell International space shuttle orbiter in the AEDC tunnel B hypersonic wind tunnel (test OH25A)

Tests were conducted in a hypersonic wind tunnel using various truncated space shuttle orbiter configurations in an attempt to establish the optimum model size for other tests examining body shock-wing leading edge interference effects. The tests were conducted at Mach number 8 using the phase change paint technique. A test description, tabulated data, and tracings of isotherms made from photographs taken during the test are presented