Results 31 to 40 of about 227,472 (209)

Tiling the unit square with squares and rectangles

Journal of Combinatorial Theory, Series A, 1985
Call a rectangle small if it will fit inside the unit square; call a rectangle binary if its dimensions are powers of 2. Theorem 1. If \({\mathcal S}\) is a set of small binary squares having total area greater than 1, some finite subset of \({\mathcal S}\) will tile the unit square. Theorem 2.
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A Survey of Spatial Unit Roots

Mathematics
This paper conducts a brief survey of spatial unit roots within the context of spatial econometrics. We summarize important concepts and assumptions in this area and study the parameter space of the spatial autoregressive coefficient, which leads to the ...
Badi H. Baltagi, Junjie Shu
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[3-Benzoyl-2,4-bis(3-nitrophenyl)cyclobutyl](phenyl)methanone

Acta Crystallographica Section E, 2012
The asymmetric unit of the title compound, C30H22N2O6, comprises a half-molecule of the cyclobutane derivative. The least-squares planes defined by the respective C atoms of the aromatic substituents intersect at angles of 76.81 (7) and 89.22 ...
Prakash S. Nayak, Badiadka Narayana, Hemmige S. Yathirajan, Thomas Gerber, Eric Hosten, Richard Betz   +5 more
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Is stock market development a spur to poverty reduction? Empirical evidence from selected sub-Saharan African countries

Development Studies Research, 2023
In this study, the relationship between stock market development and poverty reduction is examined in sub-Saharan African countries during the period 1993–2019.
Nicholas M. Odhiambo
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Spurious Regression

Journal of Probability and Statistics, 2009
The spurious regression phenomenon in least squares occurs for a wide range of data generating processes, such as driftless unit roots, unit roots with drift, long memory, trend and broken-trend stationarity.
D. Ventosa-Santaulària
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2,2′-(Propane-2,2-diyl)dibenzothiazole

Acta Crystallographica Section E, 2010
The two symmetry-independent molecules in the asymmetric unit of the title compound, C17H14N2S2, have similar geometry; the dihedral angles between the least-squares planes of the benzothiazole groups in the two molecules are 83.93 (3) and 81 ...
David R. Tyler, Lev N. Zakharov, Spring Melody M. Knapp   +2 more
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3,8-Dimethyl-4-oxo-3,4-dihydroquinazoline-6-carbonitrile

Acta Crystallographica Section E, 2012
In the title compound, C11H9N3O, the quinazoline unit is almost planar, with a mean deviation of 0.006 (1) Å from the least-squares plane defined by the ten constituent atoms.
Hai-Yan Tian, Jian-Cong Bi, Hong-Xia Zhang, Juan Zhang   +3 more
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Unit exponentiated Weibull model with applications

Scientific African
Developing new effective statistical distributions tailored to model data on the unit interval is essential in modern data analysis. In this article, we propose a novel distribution on the unit interval, termed the unit exponentiated Weibull distribution,
Ammar M. Sarhan, M.E. Sobh
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3,5-Bis[(pyridin-4-yl)methoxy]benzoic acid

Acta Crystallographica Section E, 2013
Single crystals of the title compound, C19H16N2O4, were obtained under hydrothermal conditions by an unintended recrystallization of the employed microcrystalline starting material.
Hong Lin, Yi-Ping Zhang
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Groups of Negations on the Unit Square [PDF]

The Scientific World Journal, 2014
The main results are about the groups of the negations on the unit square, which is considered as a bilattice. It is proven that all the automorphisms on it form a group; the set, containing the monotonic isomorphisms and the strict negations of the first (or the second or the third) kind, with the operator “composition,” is a groupG2(orG3orG4 ...
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