Physically Based Modeling Physically Based Modeling: Principles and Practice(Online Siggraph '97 Course notes) Please note: the lecture notes served from this page are copyright ©1997 by the authors (Andrew Witkin and David Baraff ). Chapters may be freely duplicated and distributed so long as no consideration is received in return, and this copyright notice remains intact. The slide sets are copyright ©1997 and may be neither distributed nor duplicated without permission of the authors. All documents on this page are in Adobe Acrobat format. Course Material
The Science Network Science@NASA Headline News Science@NASA Headline News You may have noticed that the "look and feel" of Science@NASA stories has changed. There's no cause for alarm. Our core product, simply- and clearly-told stories about NASA science, remains the same. Feedback is welcomed. A New Lifeform Takes Root on the ISSApril 26, 2014 Science@NASA Headline News — 2014A new life form is taking root on the International Space Station, and its name is "Outregeous."
Publications - Journals by Subject Ocean Science (OS) is an international open access journal dedicated to the publication and discussion of research on all aspects of ocean science, experimental, theoretical and laboratory. OS covers the fields ocean physics, ocean chemistry, biological oceanography, air-sea interactions, ocean models (physical, chemical, biological and biochemical), coastal and shelf edge processes, and paleoceanography. Aims & Scope | Editorial Board | Online Library OS | Online Library OSD How twitching frog legs and salt work Whether it's a bright blue poison dart frog or a brown, warty toad, a frog's survival is all about water. Most frogs begin their lives as jelly-like eggs that need moisture to develop. The eggs hatch into aquatic tadpoles, which breathe through gills. But frogs' need for water doesn't dry up once they're on land. So it should come as no surprise that frogs have developed some interesting adaptations to cope with their lifelong need for water. But frogs' adaptations aren't all about water or reproduction.
Young's modulus Mechanical property that measures stiffness of a solid material Young's modulus is the slope of the linear part of the stress-strain curve for a material under tension or compression. Young's modulus (proportional deformation) in the linear elastic region of a material and is determined using the formula:[1] Example: Silly Putty (increasing pressure: length increases quickly, meaning low )Aluminum (increasing pressure: length increases slowly, meaning high ) Higher Young's modulus corresponds to greater (lengthwise) stiffness. Definition[edit] Linear elasticity[edit] A solid material will undergo elastic deformation when a small load is applied to it in compression or extension. At near-zero stress and strain, the stress–strain curve is linear, and the relationship between stress and strain is described by Hooke's law that states stress is proportional to strain. Not many materials are linear and elastic beyond a small amount of deformation. Not to be confused with[edit] Usage[edit] , bulk modulus
Free Science and Video Lectures Online! TWC's Exclusive TOR:CON Index Thunderstorm Outlook The Weather Channel's Severe Weather Expert, Dr. Greg Forbes (Facebook | Twitter) developed the TOR:CON index to estimate the risk of a tornado on a given day or night near your area. (MORE: What is TOR:CON?) TOR:CON Value Descriptions 8+ Very high probability of a tornado 6 - High probability of a tornado4 - Moderate chance of a tornado nearby, but hail and/or high wind gusts possible2 - Low chance of a tornado, but hail and/or high wind gusts possible0 - Near-zero chance of a tornado or a severe thunderstorm The TOR:CON index ranges from 0 to 10. For more on all severe thunderstorm threats, including damaging winds and large hail, check our severe weather tracker page. Note: By definition, a severe thunderstorm contains one or more of the following: hail at least 1 inch in diameter, wind gusts 58 mph or higher, or a tornado. Sunday, April 27 Severe thunderstorm and tornado outbreak in the following areas (alphabetical by state): Monday, April 28 Tuesday, April 29
ACP - Home Remote Antarctic island is 'richer in biodiversity than the Galapagos' Antarctica's remote South Georgia Island boasts 90 percent of the world's fur seals, half of the world's elephant seals, is navigated by vast populations of blue whales, sperm whales and killer whales, and has beaches that can be packed shoulder-to-shoulder with nesting penguins. In total, it contains nearly 1,500 recorded species, many of which are found nowhere else on Earth. It's difficult to believe that until recently, this biological treasure was believed to be nothing more than an "inhospitable lump of rock." In fact, researchers now believe that South Georgia Island contains more species than anywhere else in the Southern Ocean, and may be the most biologically diverse remote island in the world — even more diverse than the storied Galapagos Islands, according to the Independent. "It shows you don't have to be a tropical island or in a hot part of the world to support a lot of marine life. The types of marine life around the island vary immensely.
Poisson's ratio Measure of material deformation perpendicular to loading In materials science and solid mechanics, Poisson's ratio Origin[edit] Poisson's ratio is a measure of the Poisson effect, the phenomenon in which a material tends to expand in directions perpendicular to the direction of compression. Conversely, if the material is stretched rather than compressed, it usually tends to contract in the directions transverse to the direction of stretching. It is a common observation when a rubber band is stretched, it becomes noticeably thinner. Assuming that the material is stretched or compressed in only one direction (the x axis in the diagram below): where is the resulting Poisson's ratio, is transverse strain is axial strain and positive strain indicates extension and negative strain indicates contraction. Poisson's ratio from geometry changes[edit] Length change[edit] For a cube stretched in the x-direction (see Figure 1) with a length increase of in the x direction, and a length decrease of and is then .
Strange Science: The Rocky Road to Modern Paleontology and Biology Space Weather Prediction with Cosmic Rays Introduction This Website is a gateway for space weather displays based upon cosmic ray data returned by the Spaceship Earth network of neutron monitors and from the worldwide muon detector network. The top of the site contains reduced versions of the plots that we consider most relevant for space weather prediction. Below is a brief description of the multi-national team providing data for this site. Disclaimer This is a prototype, experimental site. Participating Institutions Spaceship Earth Spaceship Earth is an 11-station network of neutron monitors strategically located to provide precise, real-time, 3-dimensional measurements of the cosmic ray angular distribution. For additional information on Spaceship Earth, neutron monitors, and space weather, please visit the home page of the University of Delaware Bartol Research Institute neutron monitor program The Muon Team Links to Space Weather Displays (with Brief Explanations) Important Note: These plots are experimental prototypes.