Periodicities of Quasar Redshifts in Large Area Surveys

We test the periodicity of quasar redshifts in the 2dF and SDSS surveys. In the overall surveys redshift peaks are already apparent in the brighter quasars. But by analyzing sample areas in detail it is shown that the redshifts fit very closely the long standing Karlssson formula and strongly suggest the existence of preferred values in the distribution of quasar redshifts. We introduce a powerful new test for groups of quasars of differing redshifts which not only demonstrates the periodicity of the redshifts, but also their physical association with a parent galaxy. Further such analyses of the large area surveys should produce more information on the properties of the periodicity.Comment: 23 pages, 14 figure

Instrument calibrates low gas-rate flowmeters

Electronically measuring the transit time of a soap bubble carried by the gas stream between two fixed points in a burette calibrates flowmeters used for measuring low gas-flow rates

IPAD: A unique approach to government/industry cooperation for technology development and transfer

A key element to improved industry productivity is effective management of Computer Aided Design / Computer Aided Manufacturing (CAD/CAM) information. To stimulate advancement, a unique joint government/industry project designated Integrated Programs for Aerospace-Vehicle Design (IPAD) was carried out from 1971 to 1984. The goal was to raise aerospace industry productivity through advancement of computer based technology to integrate and manage information involved in the design and manufacturing process. IPAD research was guided by an Industry Technical Advisory Board (ITAB) composed of over 100 representatives from aerospace and computer companies. The project complemented traditional NASA/DOD research to develop aerospace design technology and the Air Force's Integrated Computer Aided Manufacturing (ICAM) program to advance CAM technology. IPAD had unprecedented industry support and involvement and served as a unique approach to government industry cooperation in the development and transfer of advanced technology. The IPAD project background, approach, accomplishments, industry involvement, technology transfer mechanisms and lessons learned are summarized

Error analysis and corrections to pupil diameter measurements with Langley Research Center's oculometer

Factors that can affect oculometer measurements of pupil diameter are: horizontal (azimuth) and vertical (elevation) viewing angle of the pilot; refraction of the eye and cornea; changes in distance of eye to camera; illumination intensity of light on the eye; and counting sensitivity of scan lines used to measure diameter, and output voltage. To estimate the accuracy of the measurements, an artificial eye was designed and a series of runs performed with the oculometer system. When refraction effects are included, results show that pupil diameter is a parabolic function of the azimuth angle similar to the cosine function predicted by theory: this error can be accounted for by using a correction equation, reducing the error from 6% to 1.5% of the actual diameter. Elevation angle and illumination effects were found to be negligible. The effects of counting sensitivity and output voltage can be calculated directly from system documentation. The overall accuracy of the unmodified system is about 6%. After correcting for the azimuth angle errors, the overall accuracy is approximately 2%

Integral Grothendieck-Riemann-Roch theorem

We show that, in characteristic zero, the obvious integral version of the Grothendieck-Riemann-Roch formula obtained by clearing the denominators of the Todd and Chern characters is true (without having to divide the Chow groups by their torsion subgroups). The proof introduces an alternative to Grothendieck's strategy: we use resolution of singularities and the weak factorization theorem for birational maps.Comment: 24 page

Theoretical Parametric Study of the Relative Advantages of Winglets and Wing-Tip Extensions

For identical increases in bending moment, a winglet provides a greater gain in induced efficiency than tip extension. Winglet toe angle allows design trades between efficiency and root moment. A winglet shows the greatest benefit when the wing loads are heavy near the tip. Washout diminishes the benefit of either tip modification, and the gain in induced efficiency becomes a function of lift coefficient; thus, heavy wing loadings obtain the greatest benefit from a winglet, and low-speed performance is enhanced even more than cruise performance. Both induced efficiency and bending moment increase with winglet length and outward cant. The benefit of a winglet relative to a tip extension is greatest for a nearly vertical winglet. Root bending moment is proportional to the minimum weight of bending material required in the wing; thus, it is a valid index of the impact of tip modifications on a new wing design

The population growth and control of African elephants in Kruger National Park, South Africa:: Modeling, managing, and ethics concerning a threatened species

Elephants are hard to count. Despite the apparent implausibility of such a statement, it is true (at least in the wild). Although elephants are the world\u27s largest land animals, their size necessitates that they (as a species) are spread out over proportionately large distances, making accurate counts difficult and cost-intensive - many counts in parks with large (n \u3e 50) populations rely on statistical inferences that may or may not be accurate, based on data collected from aerial surveys conducted from helicopters or fixed-wing aircraft. Despite the difficulty of obtaining information, we have a vested interest in gathering these data about elephant populations because elephants are an endangered species (as of 2012, elephants are classified as vulnerable by the IUCN). Furthermore, as international awareness of and interest in conservation increases, so does the widespread sense that people generally and the African societies in direct contact with elephants specifically must act to not only protect the existing population but ensure the ability of the population to grow to a non-endangered threshold. This goal is complicated by the concurrent goal of maintaining biodiversity because of the unique elephant problem : There are not enough elephants in the world (in the sense that most conservationists and biologists believe that to guarantee the future of African elephants, there is a minimum necessary population threshold), and yet where elephants exist - indeed, thrive - there are too many of them. That is to say that many elephant populations in wildlife preserves currently are near or exceed the density at which elephant drastically change their landscapes through grazing, debarking of trees, and other ecological impacts. The author is developing a mathematical model to explain and predict population variations and outcomes. Part of evaluating the management decisions involves not only choosing actions which bring about acceptable consequences in the ecosystem, but are also in and of themselves acceptable actions to the concerned parties (for example, increasing the land available to wildlife preserves by demolishing or preventing the construction of buildings or farms might be beneficial to the elephant population but not be acceptable to the general public). Therefore, part of assessing the model and the management decisions and their outcomes must be to consider not only the numerical impacts but also the social ramifications for elephants and the ethical issues surrounding management. In this thesis the author discusses an approach to modeling and several possible applicable models, as well as discussing one particular model that describes and projects the population changes and constraints in Kruger National Park, South Africa. This model will include several different management options, with preference placed on projected effectiveness of implementation and ethical considerations. The ultimate goal of the modeling process is to obtain a mathematical representation of the elephant population which can accurately predict the growth or decline of elephant populations for the purpose of maintaining biodiversity