340,223 research outputs found
Cathy S. Gates
No full textCathy Shapiro Gates, a Palo Alto woman who was an environmental health specialist and a community volunteer, has died. She was 57. Gates, who died on March 10, was born in February 1964
Experimental and Numerical Investigation of Flow under Sluice Gates
No full textThe flow characteristics upstream and downstream of sluice gates are studied experimentally and numerically using Reynolds averaged Navier-Stokes two-dimensional simulations with a volume of fluid method. Special attention was brought to large opening and submergence, a frequent situation in distribution canals that is little seldom addressed in the literature. Experimental results obtained by ADV measurements provide mean velocity distributions and turbulence characteristics. The flow is shown to be mostly two-dimensional. Velocity fields were simulated using renormalization group k-epsilon and Reynolds stress model turbulence models, leading to an estimation of energy and momentum correction coefficients, head loss, and bed friction. The contraction coefficient is also shown to increase with gate opening at large submergence, which is consistent with the energy-momentum balance. This result can be used to derive accurate discharge equation
Calculation of Contraction Coefficient under Sluice Gates and Application to Discharge Measurement
No full textThe contraction coefficient under sluice gates on flat beds is studied for both free flow and submerged conditions based on the principle of momentum conservation, relying on an analytical determination of the pressure force exerted on the upstream face of the gate together with the energy equation. The contraction coefficient varies with the relative gate opening and the relative submergence, especially at large gate openings. The contraction coefficient may be similar in submerged flow and free flow at small openings but not at large openings, as shown by some experimental results. An application to discharge measurement is also presented
The Mesolithic–Neolithic transition in the Iron Gates, Southeast Europe:Calibration and dietary issues
No full textThis paper discusses an aquatic reservoir effect present in Mesolithic human bone samples from the Iron Gates section of the River Danube. Its magnitude has been calculated from a comparison of the 14C ages of human bones and terrestrial mammal bones from Schela Cladovei, equivalent to 545±70 years for a 100% aquatic diet. From this, using the δ15N value of human bone collagen to estimate the proportion of aquatic food in diet, a correction factor can be applied to the human bone 14C ages. Reservoir correction makes the resultant 14C age less precise but more accurate. The reservoir effect is derived from the inclusion of aquatic resources from the River Danube in the diets of the Mesolithic inhabitants. On the basis that the Black Sea became marine around 7400 cal BC, the possibility that part of the reservoir effect derives from anadromous fish species cannot be discounted. Human remains are abundant in the Iron Gates sites and therefore potentially important for construction of archaeological chronologies. Our ability to correct for the aquatic reservoir affect has important implications for establishing accurate chronologies, especially at the Mesolithic–Neolithic transition, which was marked by a significant change in diet and subsistence
Mary Johnston Gates Papers - Accession 1306
No full textThe Mary Johnston Gates Papers consist of correspondence, minutes, histories, financial records, program notes, newspaper clippings, photographs, scrapbooks, and reference material, relating to the South Carolina Extension Homemakers’ Council, Bethel Home Demonstration Club, the and National Extension Homemakers’ Council. Most of the material in the collection range in date from the 1950’s to the 1970’s.https://digitalcommons.winthrop.edu/manuscriptcollection_findingaids/2119/thumbnail.jp
Girders of Hydraulic Gates Optimal Design
No full textAbstractMetal gates of hydraulic structures are supplied with load bearing girders. Girders, crossbeams and gates require much steel when being manufactured. Girders of hydraulic gates rational design leads to considerable cost savings. The paper describes steel hydraulic girders optimal design. Steel hydraulic girders optimal design is based on the strength theory introduced by M. Huber, R. Mises, H. Hencky and on the theory of mirror functions. With the help of out-form volume we can either calculate the optimal form for a girder with variable cross-section or the optimal height for a girder of uniform cross-section. The paper introduces hydraulic girders calculations according to the authors’ methodology
Radiocarbon and stable isotope evidence of dietary change from the Mesolithic to the Middle Ages in the iron gates: New results from Lepenski Vir
No full textA previous radiocarbon dating and stable isotope study of directly associated ungulate and human bone samples from Late Mesolithic burials at Schela Cladovei in Romania established that there is a freshwater reservoir effect of approximately 500 yr in the Iron Gates reach of the Danube River valley in southeast Europe. Using the delta(15)N values as an indicator of the percentage of freshwater protein in the human diet, the C-14 data for 24 skeletons from the site of Lepenski Vir were corrected for this reservoir effect. The results of the paired C-14 and stable isotope measurements provide evidence of substantial dietary change over the period from about 9000 BP to about 300 BR The data from the Early Mesolithic to the Chalcolithic are consistent with a 2-component dietary system, where the linear plot of isotopic values reflects mixing between the 2 end-members to differing degrees. Typically, the individuals of Mesolithic age have much heavier delta(15)N signals and slightly heavier delta(13)C, while individuals of Early Neolithic and Chalcolithic age have lighter delta(15)N and delta(13)C values. Contrary to our earlier suggestion, there is no evidence of a substantial population that had a transitional diet midway between those that were characteristic of the Mesolithic and Neolithic. However, several individuals with "Final Mesolithic" C-14 ages show delta(15)N and delta(13)C values that are similar to the Neolithic dietary pattern. Provisionally, these are interpreted either as incomers who originated in early farming communities outside the Iron Gates region or as indigenous individuals representing the earliest Neolithic of the Iron Gates. The results from Roman and Medieval age burials show a deviation from the linear function, suggesting the presence of a new major dietary component containing isotopically heavier carbon. This is interpreted as a consequence of the introduction of millet into the human food chain
Interview with Sylvester James Gates, Jr.
No full textBorn on December 15, 1950, in Tampa, Florida, Sylvester James Gates, Jr. moved frequently at an early age while his father served in the U.S. Army. When the family settled in Parramore, a historical neighborhood for Orlando residents of African descent, Gates first attended the Hannibal Square Elementary School, then Jones High School in Orlando, where he graduated as valedictorian in 1969. With the encouragement of his father, Gates studied at the Massachusetts Institute of Technology, earning his B.S. degrees in mathematics and physics (1973), as well as his Ph.D. in physics (1977).
An accomplished academic, Dr. Gates has had a distinguished professional career, serving as a junior fellow at Harvard University, research follow at the California Institute of Technology, assistant professor of applied mathematics at MIT, and professor of physics at the University of Maryland. In 1998, when he was named the John S. Toll Professor of Physics, Gates became the first African American physicist to hold an endowed chair at a major research university in the United States.
As an American theoretical physicist, Gates is known for his work on supersymmetry, supergravity, and superstring theory. He has written or co-authored over 200 research papers and articles. His Superspace: One Thousand and One Lessons in Supersymmetry (1984) is the first comprehensive title on supersymmetry and a standard textbook. He has received numerous honors and awards, including being the first recipient of the American Physical Society’s Edward A. Bouchet Award. In 2009, Gates was named a member of the President’s Council of Advisors on Science and Technology.
In addition to his research, Gates is known for advocating the importance of education and being able to easily explain complex physics theories to a non-physics audience. He is a strong advocate for science, technology, engineering, and mathematics education. In 2013, President Barack Obama awarded Dr. Gates the National Medal of Science for his contributions to science and research.
Dr. Gates is currently the Ford Foundation Professor of Physics at Brown University. On Thursday, April 12, 2018, he visited Rollins College and gave a public presentation in the SunTrust Auditorium titled “Why Am I a Theoretical Physicist?” During the session, Professor Gate explored the arc of his career and life’s trajectory in physics while reflecting on his family connection in Central Florida
Recovery at Morvin: SERPENT final report
No full textRecovery from disturbance is poorly understood in deep water, but the extent of anthropogenic impacts is becoming increasingly well documented. We used Remotely Operated Vehicles (ROV) to visually assess the change in benthic habitat after exploratory hydrocarbon drilling disturbance around the Morvin well located at 380m depth in the Norwegian Sea.An ROV, launched directly from the rig drilling the well in 2006 was used to carry out video transects around the well before drilling and immediately after. On a return to the site three years after disturbance a larger survey was conducted with a ship-launched ROV in 2009. Transects were repeated at the disturbed area and random background transects were taken. Visible drill cuttings were mapped for each survey, and positions and counts of epibenthic invertebrate megafauna were determined, revealing a fauna dominated by Cnidaria (45% of total observations) and Porifera (33%).Immediately after disturbance a visible cuttings pile extended to over 100m from the well and megafaunal density was significantly reduced (0.07 individuals m-2) in comparison to pre-drill data (0.23 ind. m-2). Three years later the visible extent of the cuttings pile had reduced in size, reaching 60m from the well and considerably less in some headings. In comparison to background transects (0.21 ind. m-2), megafaunal density was significantly reduced on the remaining cuttings (0.04m-2), but beyond the visible disturbance there was no significant difference (0.15m-2). The investigation at this site shows a return to background densities of megafaunal organisms over a large extent of the area previously disturbed. However a central area, where the initial cuttings pile was deepest, demonstrated reduced sessile megafaunal density which persisted three years after disturbance. Elevated Barium concentration and reduced sediment grain size suggests persistence of disturbance beyond the remaining visibly impacted area which may result in changes to the infaunal communities undetectable by ROV video survey
- …
