|
Douglas A. Lawson
Douglas A. Lawson (born 1947) is a geologist, paleontologist, and computer scientist. In 1971 Lawson discovered wing bone fossils from a giant pterosaur embedded in a sandstone outcropping at Big Bend National Park, Texas. At the time the fossils were found, Lawson was working with Professor Wann Langston, Jr. of the University of Texas at Austin. Lawson was at Big Bend searching for the bones of titanosaur sauropods, such as Alamosaurus, when the pterosaur bones, which he later named ''Quetzalcoatlus'', were discovered. When the discovery of the fossils was reported in 1975, ''Quetzalcoatlus'' was the largest flying creature known to have lived. A fellow researcher challenged Lawson's estimates of the dimensions of the wing architecture of ''Quetzalcoatlus''. However, Lawson responded by demonstrating that while inconsistent with those of modern-day birds, his estimates were consistent with extrapolations of other pterosaurs, such as ''Pterodactylus antiquus''. In 2010 the U.S. Na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologist
A geologist is a scientist who studies the solid, liquid, and gaseous matter that constitutes Earth and other terrestrial planets, as well as the processes that shape them. Geologists usually study geology, earth science, or geophysics, although backgrounds in physics, chemistry, biology, and other sciences are also useful. Field research (field work) is an important component of geology, although many subdisciplines incorporate laboratory and digitalized work. Geologists can be classified in a larger group of scientists, called geoscientists. Geologists work in the energy and mining sectors searching for natural resources such as petroleum, natural gas, precious and base metals. They are also in the forefront of preventing and mitigating damage from natural hazards and disasters such as earthquakes, volcanoes, tsunamis and landslides. Their studies are used to warn the general public of the occurrence of these events. Geologists are also important contributors to climate ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolving Systems
In philosophy, systems theory, science, and art, emergence occurs when an entity is observed to have properties its parts do not have on their own, properties or behaviors that emerge only when the parts interact in a wider whole. Emergence plays a central role in theories of integrative levels and of complex systems. For instance, the phenomenon of life as studied in biology is an emergent property of chemistry. In philosophy, theories that emphasize emergent properties have been called emergentism. In philosophy Philosophers often understand emergence as a claim about the etiology of a system's properties. An emergent property of a system, in this context, is one that is not a property of any component of that system, but is still a feature of the system as a whole. Nicolai Hartmann (1882–1950), one of the first modern philosophers to write on emergence, termed this a ''categorial novum'' (new category). Definitions This concept of emergence dates from at least the tim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard Levins
Richard "Dick" Levins (June 1, 1930 – January 19, 2016) was an ex-tropical farmer turned ecologist, a population geneticist, biomathematician, mathematical ecologist, and philosopher of science who researched diversity in human populations. Until his death, Levins was a university professor at the Harvard T.H. Chan School of Public Health and a long-time political activist. He was best known for his work on evolution and complexity in changing environments and on metapopulations. Levins also had written on philosophical issues in biology and modelling. One of his influential articles is "The Strategy of Model Building in Population Biology". He has influenced a number of contemporary philosophers of biology. Levins often boasted publicly that he was a 'fourth generation Marxist' and often had said that the methodology in his ''Evolution in Changing Environments'' was based upon the introduction to Marx's ''Grundrisse'', the author's notes (not published until 1939) for ''Da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Community Matrix
In mathematical biology, the community matrix is the linearization of the Lotka–Volterra equation at an equilibrium point. The eigenvalues of the community matrix determine the Lyapunov stability, stability of the equilibrium point. The Lotka–Volterra predator–prey model is : \begin \dfrac &=& x(\alpha - \beta y) \\ \dfrac &=& - y(\gamma - \delta x), \end where ''x''(''t'') denotes the number of prey, ''y''(''t'') the number of predators, and ''α'', ''β'', ''γ'' and ''δ'' are constants. By the Hartman–Grobman theorem the non-linear system is Topological conjugacy, topologically equivalent to a linearization of the system about an equilibrium point (''x''*, ''y''*), which has the form : \begin \frac \\ \frac \end = \mathbf \begin u \\ v \end, where ''u'' = ''x'' − ''x''* and ''v'' = ''y'' − ''y''*. In mathematical biology, the Jacobian matrix \mathbf evaluated at the equilibrium point (''x''*, ''y''*) is called the community matrix. By the stable manifold theorem, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flying Wing
A flying wing is a tailless fixed-wing aircraft that has no definite fuselage, with its crew, payload, fuel, and equipment housed inside the main wing structure. A flying wing may have various small protuberances such as pods, nacelles, blisters, booms, or vertical stabilizers. Similar aircraft designs, that are not technically flying wings, are sometimes casually referred to as such. These types include blended wing body aircraft and lifting body aircraft, which have a fuselage and no definite wings. A pure flying wing is theoretically the lowest drag design configuration for a fixed wing aircraft. However, because it lacks conventional stabilizing surfaces and the associated control surfaces, in its purest form the flying wing suffers from being unstable and difficult to control. The basic flying wing configuration became an object of significant study during the 1920s, often in conjunction with other tailless designs. In the Second World War, both Nazi Germany and the A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John K
John K may refer to: *John Kricfalusi Michael John Kricfalusi ( ; born September 9, 1955), known professionally as John K., is a Canadian illustrator, blogger, voice actor and former animator. He is the creator of the animated television series ''The Ren & Stimpy Show'', which was ..., Canadian animator and voice actor * John K (musician), American singer See also * John Kay (other) * John Kaye (other) * {{hndis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleoecology
Paleoecology (also spelled palaeoecology) is the study of interactions between organisms and/or interactions between organisms and their environments across geologic timescales. As a discipline, paleoecology interacts with, depends on and informs a variety of fields including paleontology, ecology, climatology and biology. Paleoecology emerged from the field of paleontology in the 1950s, though paleontologists have conducted paleoecological studies since the creation of paleontology in the 1700s and 1800s. Combining the investigative approach of searching for fossils with the theoretical approach of Charles Darwin and Alexander von Humboldt, paleoecology began as paleontologists began examining both the ancient organisms they discovered and the reconstructed environments in which they lived. Visual depictions of past marine and terrestrial communities have been considered an early form of paleoecology. Overview of paleoecological approaches * Classic paleoecology uses data from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synecology
In ecology, a community is a group or association of populations of two or more different species occupying the same geographical area at the same time, also known as a biocoenosis, biotic community, biological community, ecological community, or life assemblage. The term community has a variety of uses. In its simplest form it refers to groups of organisms in a specific place or time, for example, "the fish community of Lake Ontario before industrialization". Community ecology or synecology is the study of the interactions between species in communities on many spatial and temporal scales, including the distribution, structure, abundance, demography, and interactions between coexisting populations. The primary focus of community ecology is on the interactions between populations as determined by specific genotypic and phenotypic characteristics. Community ecology also takes into account abiotic factors that influence species distributions or interactions (e.g. annual temperat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jackson School Of Geosciences
The Jackson School of Geosciences at The University of Texas at Austin unites the Department of Geological Sciences with two research units, the Institute for Geophysics and the Bureau of Economic Geology. The Jackson School is both old and new. It traces its origins to a Department of Geology founded in 1888 but became a separate unit at the level of a college only on September 1, 2005. The school's formation resulted from gifts by the late John A. and Katherine G. Jackson initially valued at $272 million. The school's endowment as of December 31, 2015 is $442.3 million. Dr. Claudia Mora is the Dean of the Jackson School of Geosciences. Academics The Department of Geological Sciences offers the following undergraduate degree programs: Bachelor of Arts, Bachelor of Science in General Geology, Bachelor of Science in Environmental Science, Bachelor of Science in Geophysics, Bachelor of Science in Hydrogeology/Environmental Geology, Bachelor of Science in Teaching, Bachelor of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Texas At Austin
The University of Texas at Austin (UT Austin, UT, or Texas) is a public research university in Austin, Texas. It was founded in 1883 and is the oldest institution in the University of Texas System. With 40,916 undergraduate students, 11,075 graduate students and 3,133 teaching faculty as of Fall 2021, it is also the largest institution in the system. It is ranked among the top universities in the world by major college and university rankings, and admission to its programs is considered highly selective. UT Austin is considered one of the United States's Public Ivies. The university is a major center for academic research, with research expenditures totaling $679.8 million for fiscal year 2018. It joined the Association of American Universities in 1929. The university houses seven museums and seventeen libraries, including the LBJ Presidential Library and the Blanton Museum of Art, and operates various auxiliary research facilities, such as the J. J. Pickle Research Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swarm Intelligence
Swarm intelligence (SI) is the collective behavior of decentralized, self-organized systems, natural or artificial. The concept is employed in work on artificial intelligence. The expression was introduced by Gerardo Beni and Jing Wang in 1989, in the context of cellular robotic systems. SI systems consist typically of a population of simple agents or boids interacting locally with one another and with their environment.Hu, J.; Turgut, A.; Krajnik, T.; Lennox, B.; Arvin, F.,Occlusion-Based Coordination Protocol Design for Autonomous Robotic Shepherding Tasks IEEE Transactions on Cognitive and Developmental Systems, 2020. The inspiration often comes from nature, especially biological systems. The agents follow very simple rules, and although there is no centralized control structure dictating how individual agents should behave, local, and to a certain degree random, interactions between such agents lead to the emergence of "intelligent" global behavior, unknown to the individual a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southwest Airlines
Southwest Airlines Co., typically referred to as Southwest, is one of the major airlines of the United States and the world's largest low-cost carrier. It is headquartered in Dallas, Texas, and has scheduled service to 121 destinations in the United States and 10 additional countries. , Southwest carried more domestic passengers than any other United States airline. The airline was established on March 15, 1967, by Herb Kelleher and Rollin King as Air Southwest Co. and adopted its current name, Southwest Airlines Co., in 1971, when it began operating as an intrastate airline wholly within the state of Texas, first flying between Dallas, Houston, and San Antonio. It began regional interstate service in 1979, expanding nationwide in the following decades. Southwest currently serves airports in 42 states and multiple Central American destinations. Southwest's business model is distinct from other US airlines as it uses a rolling hub and point-to-point network and allows free che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
