The development of a power system simulator using multiple microprocessors

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Coupled-cluster calculations of properties of Boron atom as a monovalent system

We present relativistic coupled-cluster (CC) calculations of energies, magnetic-dipole hyperfine constants, and electric-dipole transition amplitudes for low-lying states of atomic boron. The trivalent boron atom is computationally treated as a monovalent system. We explore performance of the CC method at various approximations. Our most complete treatment involves singles, doubles and the leading valence triples. The calculations are done using several approximations in the coupled-cluster (CC) method. The results are within 0.2-0.4% of the energy benchmarks. The hyperfine constants are reproduced with 1-2% accuracy

Imaging and quantum efficiency measurement of chromium emitters in diamond

We present direct imaging of the emission pattern of individual chromium-based single photon emitters in diamond and measure their quantum efficiency. By imaging the excited state transition dipole intensity distribution in the back focal plane of high numerical aperture objective, we determined that the emission dipole is oriented nearly orthogonal to the diamond-air interface. Employing ion implantation techniques, the emitters were engineered with various proximities from the diamond-air interface. By comparing the decay rates from the single chromium emitters at different depths in the diamond crystal, an average quantum efficiency of 28% was measured.Comment: 11 pages and 4 figure

Properties from relativistic coupled-cluster without truncation: hyperfine constants of 25Mg+^{25}{\rm Mg}^+, 43Ca+^{43}{\rm Ca}^+ , 87Sr+^{87}{\rm Sr}^+ and 137Ba+^{137}{\rm Ba}^+

We demonstrate an iterative scheme for coupled-cluster properties calculations without truncating the dressed properties operator. For validation, magnetic dipole hyperfine constants of alkaline Earth ions are calculated with relativistic coupled-cluster and role of electron correlation examined. Then, a detailed analysis of the higher order terms is carried out. Based on the results, we arrive at an optimal form of the dressed operator. Which we recommend for properties calculations with relativistic coupled-cluster theory.Comment: 13 pages, 4 figures, 5 table

Heat-transfer and pressure measurements on a simulated elevon deflected 30 deg near flight conditions at Mach 7

Heat transfer rates and pressures were obtained on an elevon plate (deflected 30 deg) and a flat plate upstream of the elevon in an 8 foot high-temperature structures tunnel. The flight Reynolds number and flight total enthalpy for altitudes of 26.8 km and 28.7 km at Mach seven were duplicated. The heat transfer and pressure data were used to establish heating and pressure loads. The measured heating was compared with several theoretical predictions, and the closest agreement obtained with a Schultz-Grunow reference enthalpy method of calculation

Open charm tomography of cold nuclear matter

We study the relative contribution of partonic sub-processes to D meson production and D meson-triggered inclusive di-hadrons to lowest order in perturbative QCD. While gluon fusion dominates the creation of large angle DD-bar pairs, charm on light parton scattering determines the yield of single inclusive D mesons. The distinctly different non-perturbative fragmentation of c quarks into D mesons versus the fragmentation of quarks and gluons into light hadrons results in a strong transverse momentum dependence of anticharm content of the away-side charm-triggered jet. In p+A reactions, we calculate and resum the coherent nuclear-enhanced power corrections from the final state partonic scattering in the medium. We find that single and double inclusive open charm production can be suppressed as much as the yield of neutral pions from dynamical high-twist shadowing. Effects of energy loss in p+A collisions are also investigated phenomenologically and may lead to significantly weaker transverse momentum dependence of the nuclear attenuation.Comment: 24 pages, 21 figure

Sheep

Sheep production in South Dakota has been increasing from year to year, reaching its greatest development at the beginning of 1,934 with approximately 1,300,000 ewes and ewe lambs on South Dakota farms and ranches. In spite of a series of dry seasons this number has been reduced but slightly and it may be said that the state\u27s sheep breeding population remains well above a million head annually. The more recent development has been in the farm flocks in the eastern part of the state, farmers realizing that sheep are coming through with two cash returns annually – one on wool and the other on meat

Better Agriculture Through Research in South Dakota, 1887-1956

Agricultural research in South Dakota has progressed with the state. In fact, the early experimental work was begun even before South Dakota was admitted to statehood. Federal funds to establish experimental work in the Dakota Territory were made available under the Hatch Act in 1887. Accordingly, the following year the first main experiment station was established in South Dakota State College, Brookings. There were five departments at the start – agriculture, botany-horticulture and forestry, chemistry, entomology, and veterinary science. Each department employed by one scientist. (See more in text

The County Farm Bureau & County Agent in South Dakota

The Farm Bureau and the County Agent movement was started in South Dakota in 1913 when Codington and Spink Counties organized for the purpose of securing the services of a County Agricultural Agent. This was two years prior to the enactment of the present South Dakota Farm Bureau law, but the farmers of those counties saw the value of Farm Bureau work and through personal efforts secured financial assistance form the county and the United State Department of Agriculture for employing a county agent. When the Smith-Lever Act was passed by Congress in 1914, it gave an immense impetus to the Farm Bureau movement as it provided financial aid for every county in the United States organized for the work. South Dakota very quickly prepared to avail herself of the government’s cooperation by passing Senate Bill No. 258 during the 1915 legislative session, thereby providing for the incorporation of County Farm Bureaus and for financial aid for each organized County Bureau

Basic Treatment of QCD Phase Transition Bubble Nucleation

Starting from the QCD Lagrangian and the surface tension of QCD bubbles we derive the critical size of bubbles, the nucleation probability and the nucleation site separation distance. We find the separation of sites is more than an order of magnitude larger than previous QCD model estimates, which could lead to observable effects.Comment: 8 pages, one figur