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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

A search for new isomers with a rapid entractor.

Turcotte, Ronald E. January 1972 (has links)
No description available.
22

Does a day make a difference? a comparison of half-day and full-day kindergarten programs in two Ohio school districts /

Mcintosh, Candace L. January 2006 (has links)
Thesis (Ed. D.)--Miami University, Dept. of Educational Leadership, 2006. / Title from second page of PDF document. Includes bibliographical references (p. 68-70).
23

Design and analysis of MIMO cooperative relaying systems

Almradi, Ahmed Mohamed Ahmed January 2017 (has links)
Cooperative relaying techniques have recently received significant interests from both academia and industry due to their ability to provide spatial diversity to address the ever increasing demand for extended network coverage, higher data rates without sacrificing extra power resources, greater mobility and enhanced reliability. This thesis mainly considers two themes. Firstly, in the context of self-powered multiple-input-multiple-output (MIMO) full-duplex (FD) relaying, our research focuses on design and performance analysis of MIMO FD relaying systems in the presence of practical transmission impairments. Namely, the impact of spatial fading correlation, imperfect channel state information (CSI), loopback self-interference (LI), and co-channel interference (CCI) on the system performance are investigated. Secondly, in the context of wirelessly-powered MIMO HD relaying, our research focuses on energy beamforming which is used to maximize the overall harvested energy so as to enable longer-distance wireless power transfer when compared to the single antenna nodes. Namely, in the presence of MIMO relaying systems, hop-by-hop information and energy beamforming is proposed where the transmitted signal is steered along the strongest eigenmode of each hop. The wirelessly powered relay scavenge energy from the source information radio-frequency (RF) signal through energy beamforming, where both the time-switching receiver (TSR) and power-splitting receiver (PSR) are considered, then uses the harvested energy to forward the source message to the destination. Our research focuses on developing a comprehensive analytical framework for deriving new closed-form expressions for the outage probability and ergodic capacity for amplify-and-forward (AF) relaying systems, including simpler tight bounds and asymptotic high signal-to-noise (SNR) ratio analysis. First, the optimization problem for the design of source, relay, and destination precoding and/or decoding weight vectors which maximizes the overall signal-to-interference-plus-noise ratio (SINR) is formulated. Then, in order to get closed-form precoding and decoding weight vectors, a sub-optimal solution based on null space projection designed to completely suppress the LI and/or CCI is proposed, through which a closed-form overall SINR is presented. Simulation results show the exactness and tightness of the proposed exact and bound analytical expressions, respectively.
24

Spin polarised tunnel junctions based on half-metallic manganites

Jo, Moon-Ho January 2001 (has links)
No description available.
25

Metric Half-Spaces

Dooley, Willis L. 05 1900 (has links)
This paper is a study of some of the basic properties of the metric half-space topology, a topology on a set which is derived from a metric on the set. In the first it is found that in a complete inner product space, the metric half-space topology is the same as one defined in terms of linear functionals on the space. In the second it is proven that in Rn the metric half-space topology is the same as the usual metric topology. In the third theorem it is shown that in a certain sense the nature of the metric halfspace topology generated by a norm on the space determines whether the norm is quadratic, that is to say, whether or not there exists an inner product on the space with the property that |x|^2=(x,x) for all x in the space.
26

Evolution of the Lower Cretaceous Chifeng Half-Graben Basins, Inner Mongolia, China

Friedman, Scott Joshua 01 May 2009 (has links)
As a result of complex extensional tectonics in northeast China and southern portions of Mongolia, some workers have interpreted the Cretaceous Maanshan Uplift and associated Chifeng basins as metamorphic core complex. Previous work has relied solely upon kinematic indicators to determine the structural origin of these basins. To fully understand the creation of these basins, the sedimentiological record was analyzed in this study. The early Cretaceous sedimentary fill of these basins was analyzed to determine if it is synextensional in nature, and if so what manner of extension was in progress during that deposition. The Chifeng basins are filled with four distinct facies associations and are floored by Late Jurassic and Early Cretaceous volcanics of intermediate and felsic composition. The facies associations observed are interpreted as lacustrine/fluvial deposits, alluvial fan conglomerates, distal fan deposits with fluvial deposits, and hanging wall derived fluvial deposits. These facies are composed of sediment shed from the footwall and hanging wall of the master faults and volcanic deposits. Paleocurrent indicators, primarily in the form of imbrication, along with clast count data show provenance directly off the structure separating the two basins and from the eastern margin of the southeast basin. The distribution of facies, as well as paleocurrent data, provenance data, and structural geometry, implies that these basins are of half-graben origin and that no sedimentological evidence exists of an Early Cretaceous metamorphic core complex near Chifeng.
27

A search for new isomers with a rapid entractor.

Turcotte, Ronald E. January 1972 (has links)
No description available.
28

Simulation of Tri-Axially Braided Composites Half-Cylinder Behavior During Balistic Impact

Staniszewski, Marcin C. 08 August 2007 (has links)
No description available.
29

The synthesis and unexpected solution chemistry of thermochromic carborane-containing osmium half-sandwich complexes

Pitto-Barry, Anaïs, South, A., Rodger, A., Barry, Nicolas P.E. 24 December 2015 (has links)
Yes / The functionalisation of the 16-electron complex [Os(η6-p-cymene)(1,2-dicarba-closo-dodecarborane- 1,2-dithiolato)] (1) with a series of Lewis bases to give the 18-electron complexes of general formula [Os(η6-p-cymene)(1,2-dicarba-closo-dodecarborane-1,2-dithiolato)(L)] (L = pyridine (2), 4-dimethylaminopyridine (3), 4-cyanopyridine (4), 4-methoxypyridine (5), pyrazine (6), pyridazine (7), 4,4’-bipyridine (8) and triphenylphosphine (9)) is reported. All 18-electron complexes are in equilibrium in solution with the 16-electron precursor, and thermochromic properties are observed in some cases (2, 3, 5, 8, and 9). The binding constants and Gibbs free energies of the equilibria are determined using UV-visible titrations and their stabilities investigated. Synthetic routes for forcing the formation of the 18-electron species are proposed, and analytical methods to characterise the equilibria are described. / We thank the Leverhulme Trust (Early Career Fellowship No. ECF-2013-414 to NPEB), and the University of Warwick (Grant No. RD14102 to NPEB).
30

A Relative Method for Determination of Nuclear Decay Rates

Burgess, Donald D. 07 1900 (has links)
<p> The performance of a relative decay rate measurement technique was investigated. Determinations of the half-lives of the isotopes copper-64 and ruthenium-97 in various chemical states were attempted as illustrations of the use of the method. Applications of the technique are suggested.</p> / Thesis / Master of Science (MSc)

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