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Optimizing the Geometry of Pyramidal Antenna Arrays for Hemispherical Scan Coverage
2006 IEEE Antennas and Propagation Society International Symposium, 2006A new, simple approach for determining the optimal face elevation of pyramidal antenna arrays, used for full or partial hemispherical scan coverage, has been presented. This paper shows that when finite hemisphere radii and pyramidal antenna dimensions are considered, the optimal face elevation remains unchanged, while the maximum scan angle changes ...
I. Khalifa, R. Vaughan
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The Journal of Chemical Physics, 2020
The pyramidalization angle and spherical curvature are well-known quantities used to characterize the local geometry of a molecule and to provide a measure of regio-chemical activity of molecules. In this paper, we give a self-contained presentation of these two concepts and discuss their limitations.
Julia Sabalot-Cuzzubbo +3 more
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The pyramidalization angle and spherical curvature are well-known quantities used to characterize the local geometry of a molecule and to provide a measure of regio-chemical activity of molecules. In this paper, we give a self-contained presentation of these two concepts and discuss their limitations.
Julia Sabalot-Cuzzubbo +3 more
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Toward stabilizing rectangular-pyramidal geometries in non-metals: polycyclic phosphorus esters
Inorganic Chemistry, 1991The preparation of some novel polycyclic phosphorus compounds is reported. Some chemical reactions of the compounds are discussed, and crystallographic parameters of the compounds are reported. 10 tables, 7 figures, 60 ref.
R. V. Davis +9 more
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Optimized Geometries and Pyramidal Inversion in s3l3-Phosphole: A Brief Theoretical Treatment
HETEROCYCLES, 1992Optimized geometries and total energies for the pyramidal and planar conformations of σ 3 λ 3 -phosphole have been calculated by ab initio methods using the 6-311G * basis set and the GAUSSIAN 86 series of programs.
Alan N. Hughes, Kenneth E. Edgecombe
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Pyramid as test geometry to evaluate formability in incremental forming: Recent results
Journal of Mechanical Science and Technology, 2012The present work has been undertaken with an objective to fill the gaps of previous studies and to explore guidelines to standardize the test specimen for evaluating formability with a single specimen in single point incremental forming (SPIF). Two candidate geometries for formability testing (i.e.
Ghulam Hussain, Nasir Hayat, Gao Lin
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Truncated-inverted-pyramid light emitting diode geometry optimisation using ray tracing technique
IEE Proceedings - Optoelectronics, 2003The authors have optimised light emitting diodes (LED) of truncated-inverted-pyramid (TIP) geometry using the ray tracing technique together with electronics simulation. A unique feature of their ray tracing technique is the geometrical treatment combined with a wave optics approach, taking into account refraction, reflection, absorption and ...
O. Shmatov, Z.S. Li
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Practical Geometry Problems: The Case of the Ritzville Pyramids
The Mathematics Teacher, 1993The wheat-producing country of eastern Washington state furnishes a practical example of an applied geometry problem requiring only a knowledge of the relationship between the parts of a circle and the parts of a right triangle. The solution of this problem is related to several topics in the Curriculum and Evaluation Standards (NCTM 1989) that do not ...
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Nerve cells with irregular processes: Demonstration of anisotropic core geometry of a pyramidal cell
Neuroscience, 1988An analytical, recursive method has been developed to demonstrate the anisotropic electrotonic geometry of nerve cells containing varicose or spiny dendrites. The procedure has been based on the distribution of the core geometry of dendrites into modules which consist of module elements where the physical length is much shorter than the actual space ...
F, Pongrácz, J, Martos, F, Zsuppán
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ChemInform, 1991
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
R. V. DAVIS +9 more
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AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
R. V. DAVIS +9 more
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Applying Solar Geometry to Understand the Foundation Rituals of ‘Old Kingdom’ Egyptian Pyramids
Architectural Science Review, 2008Abstract The republication of the interesting book by Rossi (2003, 2007) has provoked questions about the orientation of Egyptian pyramids from the architectural science point of view. The main concern of this paper is to explain several hypothetical possibilities for orientation of the first step Egyptian pyramid.
Richard Kittler, Stanislav Darula
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