Gflow 2000, which was developed by Haitjema Software, is described as a highly efficient stepwise groundwater flow modeling system. It is based on the analytic element method and models steady state flow in a single heterogeneous aquifer using the Dupuit-Forchheimer assumption, and is particularly suitable for modeling regional horizontal flow. The free educational version of the software is available for download from the site, as well as descriptions of the analytic method, stepwise modeling,
"The Astromaterials Acquisition and Curation Office at the Johnson Space Center is tasked to curate NASA's current and future collections of extraterrestrial samples." The website divides the collections into six categories: Rocks and Soils from the Moon, Meteorites from Antarctica, Stratospheric Dust, Solar Wind, Space-Exposed Hardware, and Stardust Mission Samples. Besides learning how to receive and return the samples, users can find newsletters and information on discoveries made using the s
ECOTOX Database System
The US Environmental Protection Agency (EPA) provides this database of chemical toxicity. Three individual EPA databases are combined to provide information on chemical-specific toxicity values for aquatic and terrestrial plants and animals. Users can search for research reports by chemical name, species name, or environmental effect. The site has informative help files and browse features. This Web site is useful for evaluating industrial chemicals or for environmental assessment research.
Conservation International: Biodiversity Hotspots
From Conservation International, this Biodiversity Hotspots site (first reported on in the October 18, 2002 NSDL Scout Report for Life Sciences) "was re-launched in 2005 with completely updated information as presented in the new book _Hotspots Revisited_." The updated Hotspots website features profiles of more than 30 ecologically important areas of the world. Hotspots are categorized under five world regions including South America, Africa, North and Central America, Europe and Central Asia, a
Super Bowl Technology
One of the biggest technology stories surrounding Super Bowl XXXVII was the security measures used to spot disruptive activity and terrorists. The massive network of cameras that was used to monitor the entire stadium is described in this story (1). It also discusses police operations, face recognition systems, and entrance sensors. The Houston Texans were not in the Super Bowl for 2003, but their stadium is certainly classified as hi-tech. The Reliant Stadium (2) is the first in the NFL to have
African Elephant Specialist Group
The African Elephant Specialist Group (AfESG) operates under the auspices of the Species Survival Commission of the World Conservation Union (IUCN). The AfESG is composed "of technical experts focusing on the conservation and management of African elephants. The broad aim of the AfESG is to promote the long-term conservation of Africa's elephants and, where possible, the recovery of their population to viable levels." The AfESG website contains useful information for conservationists, wildlife m
MIT OpenCourseWare: Fields, Forces, and Flows in Biological Systems
Materials from this intriguingly titled Massachusetts Institute of Technology (MIT) course about biological systems are freely available to students, educators, and others through MIT's OpenCourseWare. The course covers a variety of topics including "conduction, diffusion, convection in electrolytes; fields in heterogeneous media; electrical double layers; Maxwell stress tensor and electrical forces in physiological systems; and fluid and sold continua: equations of motion useful for porous, hyd
The Fields Institute: Lecture Audio and Slides
The Fields Institute for Research in Mathematical Sciences aims to "enhance mathematical activity in Canada by bringing together mathematicians from Canada and abroad, and by promoting contact and collaboration between professional mathematicians and the increasing numbers of users of mathematics." They support research in pure and applied mathematics, statistics and computer science, as well as collaborative projects between mathematicians and those applying mathematics in areas such as enginee
Science Sampler : Capitalizing on student travel in Earth science classrooms
Students who take extended vacations during the school year can present a recurring challenge for educators. However, this article outlines creative strategies that will enrich students as they travel abroad, and engage them in the process of inquiry along the way.
Geological Time Scale
This information about geologic time and the geologic time scale defines the terms relative time (chronostratic) and absolute time (chronometric). Relative time can be thought of as the physical subdivisions of rock found in the Earths stratigraphy and absolute as the measurements taken upon those to determine the actual time that has expired. Absolute time measurements can be used to calibrate the relative time scale, producing an integrated geologic or geochronologic time scale. A feature of t
Function machine (grades 6-8)
Applying a machine metaphor for functions, this virtual manipulative allows the learner to examine the relationship between input (domain) and output (range). The learner inputs numbers from one to four and the virtual machine generates output information in a table. The learner is challenged to find the output for values five through seven and enter them in the table. Errors are noted automatically. Using a new function button, different types of functions are randomly offered for investigation
Seed Dispersal: Lemurs
Trees in Madagascar's forests have evolved traits that promote the dispersal of their seeds by lemurs. This two-minute radio program focuses on the interaction between forest plants and lemurs--the main seed dispersers in the forests. A guest scientist explains why lemurs ingest seeds that are large relative to their body size. He also notes that the fruits of Madagascar's trees have evolved to be strong smelling but drably colored in accordance with lemurs' keen sense of smell and poor vision.
Sounds of the Sun: Inside
A solar physicist explains the significance of the solar sounds that play in the background of this two-minute radio program. The sounds were detected by the Solar and Heliospheric Observatory (SOHO) spacecraft. The physicist addresses why the sun's sounds are not audible on Earth. Scientists analyze solar sound waves to learn more about our turbulent sun. The radio program, which is from the Pulse of the Planet show, is available here in text and audio formats. Copyright 2005 Eisenhower Nationa
Units and Cylinder Volume
Find the volume and surface area of a cylindical storage tank with a radius of 15 feet and a height of 30 feet.
History topics: Babylonian mathematics
This website contains an overview of Babylonian mathematics, with links to in-depth analyses of Babylonian numerals and Pythagoras?s theorem in Babylonian mathematics. The history of zero covers Mesopotamia, Greece, India, the Mayan people in Central America, China, and Europe. Links also give access to bibliographies of mathematicians, such as Cardan, Ch'in, Bhaskara, and Brahmagupta. Examples of written numbers using the cuneiform symbols in the sexigesimal system are included. Other terms: al
Positive Linear Function Machine
This activity allows the user to explore simple linear functions; the function is determined by looking for patterns in the outputs.
This page contains links to one pagers on historical instruments of astronomy with photos of the following : Astronomy Slides, Celestial Globe, Cometarium, Globe, Gregorian Telescope, Kepler's Laws Demonstration, Orrery, Planetarium, Planisphere, Stereoscopic Pictures of the Moon, Tellurian, and Transit.
Sunlight and the Earth : Climate and Weather
These web pages trace the processes involved in the suns impact on weather. This is an exploration of the importance of radiation and reflection of light, both visible and infra-red, and the greenhouse effect. Convection and the role of water vapor are also considered. Global-scale air flows are described, explaining why wind in the continental US usually blows from the west, while near the equator it comes from the east.
Waves and Wave Motion : Describing Waves
This module introduces the history of wave theories, basic descriptions of waves and wave motion, and the concepts of wave speed and frequency.
Project Atmosphere Canada: Teacher's Guide
This teacher's guide from Project Atmosphere Canada is designed to promote an interest in meteorology among young people, and to encourage and foster the teaching of the atmospheric sciences and related topics in Canada. Topics include weather hazards such as hurricanes and thunderstorms; the use of radar and satellites in weather prediction; weather phenomena such as El Nino, wind patterns, high and low pressure, and clouds; sunlight, water vapor, and the upper atmopshere; and others. Each modu