Students use STELLA to create a model of heatflow in permafrost to attempt to replicate the findings of Lachenbruch and Marshall (1986), who used inflections in the geothermal gradient of Alaskan permafrost to search for evidence of climatic change.
This graphical locator makes it possible to find location data about places in the northwest quarter of the Earth. Most of the locations in this database are in the United States, but a limited number exist for Canada and Mexico. Users may choose maps by state, click directly on U.S. and hydrologic (HUC) maps, or enter latitude and longitude, township range and section, or a UTM. Data includes latitude, longitude, gradient, elevation, UTM (Universal Time) zone, legal name, state and county, topographic map names of the area and nearby named locations.
Gary P. Liney, at the University of Hull, offers an introduction to magnetic resonance physics and techniques. Users can download presentations about spin-echo and Fourier Transformation. The website discusses a host of artifacts such as Gibbs Ringing, chemical shift, and susceptibility. Students and educators can learn about the magnet, RF Coils, gradients, and other instruments used to produce MRIs. The many animations and figures help users learn about the difficult physical concepts.
This chapter provides a series of exercises associated with self-defining continuous fields where the entity is an attribute that is continuous across space and thus is in some sense self-defining. The relations are those involving distance and magnitude and there are a number of associated spatial concepts such as the first order primitive we call height, and second order notions of continuity, gradient and trend.
