Hierarchical auditory processing directed rostrally along the monkey's supratemporal plane.
Kikuchi, Yukiko; Horwitz, Barry; Mishkin, Mortimer
2010-09-29
Connectional anatomical evidence suggests that the auditory core, containing the tonotopic areas A1, R, and RT, constitutes the first stage of auditory cortical processing, with feedforward projections from core outward, first to the surrounding auditory belt and then to the parabelt. Connectional evidence also raises the possibility that the core itself is serially organized, with feedforward projections from A1 to R and with additional projections, although of unknown feed direction, from R to RT. We hypothesized that area RT together with more rostral parts of the supratemporal plane (rSTP) form the anterior extension of a rostrally directed stimulus quality processing stream originating in the auditory core area A1. Here, we analyzed auditory responses of single neurons in three different sectors distributed caudorostrally along the supratemporal plane (STP): sector I, mainly area A1; sector II, mainly area RT; and sector III, principally RTp (the rostrotemporal polar area), including cortex located 3 mm from the temporal tip. Mean onset latency of excitation responses and stimulus selectivity to monkey calls and other sounds, both simple and complex, increased progressively from sector I to III. Also, whereas cells in sector I responded with significantly higher firing rates to the "other" sounds than to monkey calls, those in sectors II and III responded at the same rate to both stimulus types. The pattern of results supports the proposal that the STP contains a rostrally directed, hierarchically organized auditory processing stream, with gradually increasing stimulus selectivity, and that this stream extends from the primary auditory area to the temporal pole.
Scott, Brian H; Leccese, Paul A; Saleem, Kadharbatcha S; Kikuchi, Yukiko; Mullarkey, Matthew P; Fukushima, Makoto; Mishkin, Mortimer; Saunders, Richard C
2017-01-01
In the ventral stream of the primate auditory cortex, cortico-cortical projections emanate from the primary auditory cortex (AI) along 2 principal axes: one mediolateral, the other caudorostral. Connections in the mediolateral direction from core, to belt, to parabelt, have been well described, but less is known about the flow of information along the supratemporal plane (STP) in the caudorostral dimension. Neuroanatomical tracers were injected throughout the caudorostral extent of the auditory core and rostral STP by direct visualization of the cortical surface. Auditory cortical areas were distinguished by SMI-32 immunostaining for neurofilament, in addition to established cytoarchitectonic criteria. The results describe a pathway comprising step-wise projections from AI through the rostral and rostrotemporal fields of the core (R and RT), continuing to the recently identified rostrotemporal polar field (RTp) and the dorsal temporal pole. Each area was strongly and reciprocally connected with the areas immediately caudal and rostral to it, though deviations from strictly serial connectivity were observed. In RTp, inputs converged from core, belt, parabelt, and the auditory thalamus, as well as higher order cortical regions. The results support a rostrally directed flow of auditory information with complex and recurrent connections, similar to the ventral stream of macaque visual cortex. Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Scott, Brian H; Saleem, Kadharbatcha S; Kikuchi, Yukiko; Fukushima, Makoto; Mishkin, Mortimer; Saunders, Richard C
2017-11-01
In the primate auditory cortex, information flows serially in the mediolateral dimension from core, to belt, to parabelt. In the caudorostral dimension, stepwise serial projections convey information through the primary, rostral, and rostrotemporal (AI, R, and RT) core areas on the supratemporal plane, continuing to the rostrotemporal polar area (RTp) and adjacent auditory-related areas of the rostral superior temporal gyrus (STGr) and temporal pole. In addition to this cascade of corticocortical connections, the auditory cortex receives parallel thalamocortical projections from the medial geniculate nucleus (MGN). Previous studies have examined the projections from MGN to auditory cortex, but most have focused on the caudal core areas AI and R. In this study, we investigated the full extent of connections between MGN and AI, R, RT, RTp, and STGr using retrograde and anterograde anatomical tracers. Both AI and R received nearly 90% of their thalamic inputs from the ventral subdivision of the MGN (MGv; the primary/lemniscal auditory pathway). By contrast, RT received only ∼45% from MGv, and an equal share from the dorsal subdivision (MGd). Area RTp received ∼25% of its inputs from MGv, but received additional inputs from multisensory areas outside the MGN (30% in RTp vs. 1-5% in core areas). The MGN input to RTp distinguished this rostral extension of auditory cortex from the adjacent auditory-related cortex of the STGr, which received 80% of its thalamic input from multisensory nuclei (primarily medial pulvinar). Anterograde tracers identified complementary descending connections by which highly processed auditory information may modulate thalamocortical inputs. © 2017 Wiley Periodicals, Inc.
International Nuclear Information System (INIS)
Utsunomiya, H.; Nawata, M.; Ogasawara, T.; Okazaki, M.; Miyoshi, M.
1996-01-01
The planum temporale of the supratemporal plane is important for language function and shows left-right asymmetry in most brains. To estimate the size and allow side comparison of the planum temporale, we developed a new technique for 3-D MR analysis of the supratemporal plane using a personal computer and computer-aided graphics. The temporal lobes of 5 human cadavers were imaged by MR in the sagittal plane, at a slice thickness of 3 mm. The images of the supratemporal plane were entered into a personal computer using the original software to determine the positions of anatomic landmarks and the size of the planum temporale. The data were then transferred to a supercomputer to reconstruct the 3-D surface image of the supratemporal plane. Computer images of the spuratemporal plane agreed with macroscopic observations. The positions of anatomic landmarks and the size of the planum temporale also agreed with macroscopic measurements. Thus, the persent technique provides valuable anatomic data on the spuratemporal plane which should be useful for further clarification of the anatomic basis of language function. (orig.)
A novel supra-temporal approach to retrobulbar anaesthesia in dogs: Preliminary study in cadavers.
Chiavaccini, Ludovica; Micieli, Fabiana; Meomartino, Leonardo; Duffee, Lauren R; Vesce, Giancarlo
2017-05-01
A novel supra-temporal technique for retrobulbar anaesthesia in dogs is described and compared to the inferior temporal palpebral approach. Supra-temporal and inferior temporal palpebral retrobulbar injections were performed in 20 orbits of canine cadavers. Distribution of injected contrast medium within the intraconal space and around the optic nerve was analysed using computed tomography. There was adequate distribution of contrast medium within the intraconal space with both techniques. Concurrent intraconal and extraconal distribution was observed using the inferior temporal palpebral approach in 3/10 orbits and using the supra-temporal approach in 5/10 orbits. In 3/10 supra-temporal injections, the injected vehicle was distributed preferentially in the caudal aspect of the retrobulbar cone, closer to the orbital fissure. Accidental intraocular injection was never observed. The supra-temporal approach appears to be a valid alternative to the inferior temporal palpebral approach for retrobulbar anaesthesia in dogs, being less technically challenging. Further studies are required to confirm the clinical efficacy of this approach in dogs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Wilbrink, H.A.
1982-01-01
In this paper we develop a theory for nearaffine planes analogous to the theory of ordinary affine translation planes. In a subsequent paper we shall use this theory to give a characterization of a certain class of Minkowski planes.
Existence of Projective Planes
Perrott, Xander
2016-01-01
This report gives an overview of the history of finite projective planes and their properties before going on to outline the proof that no projective plane of order 10 exists. The report also investigates the search carried out by MacWilliams, Sloane and Thompson in 1970 [12] and confirms their result by providing independent verification that there is no vector of weight 15 in the code generated by the projective plane of order 10.
Cross plane scattering correction
International Nuclear Information System (INIS)
Shao, L.; Karp, J.S.
1990-01-01
Most previous scattering correction techniques for PET are based on assumptions made for a single transaxial plane and are independent of axial variations. These techniques will incorrectly estimate the scattering fraction for volumetric PET imaging systems since they do not take the cross-plane scattering into account. In this paper, the authors propose a new point source scattering deconvolution method (2-D). The cross-plane scattering is incorporated into the algorithm by modeling a scattering point source function. In the model, the scattering dependence both on axial and transaxial directions is reflected in the exponential fitting parameters and these parameters are directly estimated from a limited number of measured point response functions. The authors' results comparing the standard in-plane point source deconvolution to the authors' cross-plane source deconvolution show that for a small source, the former technique overestimates the scatter fraction in the plane of the source and underestimate the scatter fraction in adjacent planes. In addition, the authors also propose a simple approximation technique for deconvolution
Fourier plane imaging microscopy
Energy Technology Data Exchange (ETDEWEB)
Dominguez, Daniel, E-mail: daniel.dominguez@ttu.edu; Peralta, Luis Grave de [Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Nano Tech Center, Texas Tech University, Lubbock, Texas 79409 (United States); Alharbi, Nouf; Alhusain, Mdhaoui [Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Bernussi, Ayrton A. [Nano Tech Center, Texas Tech University, Lubbock, Texas 79409 (United States); Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States)
2014-09-14
We show how the image of an unresolved photonic crystal can be reconstructed using a single Fourier plane (FP) image obtained with a second camera that was added to a traditional compound microscope. We discuss how Fourier plane imaging microscopy is an application of a remarkable property of the obtained FP images: they contain more information about the photonic crystals than the images recorded by the camera commonly placed at the real plane of the microscope. We argue that the experimental results support the hypothesis that surface waves, contributing to enhanced resolution abilities, were optically excited in the studied photonic crystals.
Instabilities of Kirkendall planes
Dal, van M.J.H.; Gusak, A.M.; Cserhati, C.; Kodentsov, A.; Loo, van F.J.J.
2001-01-01
Reconsideration of the Kirkendall effect is presented. It is demonstrated (experimentally as well as theoretically) that Kirkendall planes can be multiple, stable or unstable within a single-phase reaction zone. A general criterion of instabilty is given.
Algebraic Structures on MOD Planes
Kandasamy, Vasantha; Ilanthenral, K.; Smarandache, Florentin
2015-01-01
Study of MOD planes happens to a very recent one. In this book, systematically algebraic structures on MOD planes like, MOD semigroups, MOD groups and MOD rings of different types are defined and studied. Such study is innovative for a large four quadrant planes are made into a small MOD planes. Several distinct features enjoyed by these MOD planes are defined, developed and described.
Transformational plane geometry
Umble, Ronald N
2014-01-01
Axioms of Euclidean Plane Geometry The Existence and Incidence Postulates The Distance and Ruler Postulates The Plane Separation Postulate The Protractor Postulate The Side-Angle-Side Postulate and the Euclidean Parallel Postulate Theorems of Euclidean Plane Geometry The Exterior Angle Theorem Triangle Congruence Theorems The Alternate Interior Angles Theorem and the Angle Sum Theorem Similar Triangles Introduction to Transformations, Isometries, and Similarities Transformations Isometries and SimilaritiesAppendix: Proof of Surjectivity Translations, Rotations, and Reflections Translations Rotations Reflections Appendix: Geometer's Sketchpad Commands Required by Exploratory Activities Compositions of Translations, Rotations, and Reflections The Three Points Theorem Rotations as Compositions of Two Reflections Translations as Compositions of Two Halfturns or Two Reflections The Angle Addition Theorem Glide Reflections Classification of Isometries The Fundamental Theorem and Congruence Classification of Isometr...
DEFF Research Database (Denmark)
Jensen, Jonas
This PhD project investigates and further develops methods for ultrasound plane wave imaging and blood flow estimation with the objective of overcoming some of the major limitations in conventional ultrasound systems, which are related to low frame rates and only estimation of velocities along...... the ultrasound beam. The first part of the contribution investigates the compromise between frame rate and plane wave image quality including the influence of grating lobes from a λ-pitch transducer. A method for optimizing the image quality is suggested, and it is shown that the frame rate can be increased...... healthy volunteers. Complex flow patterns were measured in an anthropomorphic flow phantom and showed good agreement with the velocity field simulated using computational fluid dynamics. The last part of the contribution investigates two clinical applications. Plane wave imaging was used for slow velocity...
DEFF Research Database (Denmark)
Manolova, Anna Vasileva; Ruepp, Sarah Renée
2010-01-01
. The applicability analysis carried out here focuses on the actual feasibility of the integration and the potential trade-offs which appear when two contradicting principles are combined. Taking advantage of the flexibility of the GMPLS control plane does not seem to be as easy and as straightforward as expected...
International Nuclear Information System (INIS)
Foda, Omar; Wheeler, Michael
2007-01-01
Using BKP neutral fermions, we derive a product expression for the generating function of volume-weighted plane partitions that satisfy two conditions. If we call a set of adjacent equal height-h columns, h > 0, an h-path, then 1. Every h-path can assume one of two possible colours. 2. There is a unique way to move along an h-path from any column to another
Energy Technology Data Exchange (ETDEWEB)
Foda, Omar; Wheeler, Michael [Department of Mathematics and Statistics, University of Melbourne, Parkville, Victoria 3010 (Australia)
2007-01-15
Using BKP neutral fermions, we derive a product expression for the generating function of volume-weighted plane partitions that satisfy two conditions. If we call a set of adjacent equal height-h columns, h > 0, an h-path, then 1. Every h-path can assume one of two possible colours. 2. There is a unique way to move along an h-path from any column to another.
Carbon nanotube plane fastener
Directory of Open Access Journals (Sweden)
Kaori Hirahara
2011-12-01
Full Text Available We report a feature of carbon nanotubes (CNTs that arises when the surfaces of two vertically-aligned CNT brushes are pressed together. Adhesion between the CNTs creates a plane fastener-like device. Observations from scanning electron microscopy and measurements of adhesion properties indicate a device-dependence on CNT density and shape near the tip region. Among other applications, such fasteners have the potential to attach small components onto micron-sized electronic devices.
Colignatus, Thomas
2011-01-01
CONQUEST OF THE PLANE provides: an integrated course for geometry and analysis a didactic build-up that avoids traditional clutter use of only the essentials for good understanding proper place for vectors, complex numbers, linear algebra and trigonometry an original and elegant development of trigonometry an original and elegant foundation for calculus examples from physics, economics and statistics integration within the dynamic environment of Mathematica ...
An Algorithm for constructing Hjelmslev planes
Hall, Joanne L.; Rao, Asha
2013-01-01
Projective Hjelmslev planes and Affine Hjelmselv planes are generalisations of projective planes and affine planes. We present an algorithm for constructing a projective Hjelmslev planes and affine Hjelsmelv planes using projective planes, affine planes and orthogonal arrays. We show that all 2-uniform projective Hjelmslev planes, and all 2-uniform affine Hjelsmelv planes can be constructed in this way. As a corollary it is shown that all 2-uniform Affine Hjelmselv planes are sub-geometries o...
Simultaneous orthogonal plane imaging.
Mickevicius, Nikolai J; Paulson, Eric S
2017-11-01
Intrafraction motion can result in a smearing of planned external beam radiation therapy dose distributions, resulting in an uncertainty in dose actually deposited in tissue. The purpose of this paper is to present a pulse sequence that is capable of imaging a moving target at a high frame rate in two orthogonal planes simultaneously for MR-guided radiotherapy. By balancing the zero gradient moment on all axes, slices in two orthogonal planes may be spatially encoded simultaneously. The orthogonal slice groups may be acquired with equal or nonequal echo times. A Cartesian spoiled gradient echo simultaneous orthogonal plane imaging (SOPI) sequence was tested in phantom and in vivo. Multiplexed SOPI acquisitions were performed in which two parallel slices were imaged along two orthogonal axes simultaneously. An autocalibrating phase-constrained 2D-SENSE-GRAPPA (generalized autocalibrating partially parallel acquisition) algorithm was implemented to reconstruct the multiplexed data. SOPI images without intraslice motion artifacts were reconstructed at a maximum frame rate of 8.16 Hz. The 2D-SENSE-GRAPPA reconstruction separated the parallel slices aliased along each orthogonal axis. The high spatiotemporal resolution provided by SOPI has the potential to be beneficial for intrafraction motion management during MR-guided radiation therapy or other MRI-guided interventions. Magn Reson Med 78:1700-1710, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.
International Nuclear Information System (INIS)
Rensburg, E J Janse van; Ma, J
2006-01-01
We examine partitions and their natural three-dimensional generalizations, plane partitions, as models of vesicles undergoing an inflation-deflation transition. The phase diagrams of these models include a critical point corresponding to an inflation-deflation transition, and exhibits multicritical scaling in the vicinity of a multicritical point located elsewhere on the critical curve. We determine the locations of the multicritical points by analysing the generating functions using analytic and numerical means. In addition, we determine the numerical values of the multicritical scaling exponents associated with the multicritical scaling regimes in these models
Duality and noncommutative planes
DEFF Research Database (Denmark)
Jøndrup, Søren
2015-01-01
We study extensions of simple modules over an associative ring A and we prove that for twosided ideals mm and nn with artinian factors the condition ExtA1(A/m,A/n)≠0 holds for the left A -modules A/mA/m and A/nA/n if and only if it holds for the right modules A/nA/n and A/mA/m. The methods pro...... proving this are applied to show that noncommutative models of the plane, i.e. algebras of the form k〈x,y〉/(f)k〈x,y〉/(f), where f∈([x,y])f∈([x,y]) are noetherian only in case (f)=([x,y])...
Semantic Versus Syntactic Cutting Planes
Filmus, Yuval; Hrube, Pavel; Lauria, Massimo
2016-01-01
In this paper, we compare the strength of the semantic and syntactic version of the cutting planes proof system. First, we show that the lower bound technique of Pudlák applies also to semantic cutting planes: the proof system has feasible interpolation via monotone real circuits, which gives an exponential lower bound on lengths of semantic cutting planes refutations. Second, we show that semantic refutations are stronger than syntactic ones. In particular, we give a formula for whic...
Gravitational Couplings for Gop-Planes and y-Op-Planes
Giraldo, Juan Fernando Ospina
2000-01-01
The Wess-Zumino actions for generalized orientifold planes (GOp-planes) and y-deformed orientifold planes (yOp-planes) are presented and two series power expantions are realized from whiches processes that involves GOp-planes,yOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally non-standard GOp-planes and y-Op-planes are showed.
Conceptual Design of Wave Plane
DEFF Research Database (Denmark)
Frigaard, Peter; Trewers, Andrew; Kofoed, Jens Peter
The Wave Plane is a patented Wave Energy device of the overtopping type, designed to capture potential as well as kinetic energy. This is as such different to other overtopping devices, who usually only focus on potential energy. If Wave Plane A/S can deliver the turbine technology to utilize both...
Generating asymptotically plane wave spacetimes
International Nuclear Information System (INIS)
Hubeny, Veronika E.; Rangamani, Mukund
2003-01-01
In an attempt to study asymptotically plane wave spacetimes which admit an event horizon, we find solutions to vacuum Einstein's equations in arbitrary dimension which have a globally null Killing field and rotational symmetry. We show that while such solutions can be deformed to include ones which are asymptotically plane wave, they do not posses a regular event horizon. If we allow for additional matter, such as in supergravity theories, we show that it is possible to have extremal solutions with globally null Killing field, a regular horizon, and which, in addition, are asymptotically plane wave. In particular, we deform the extremal M2-brane solution in 11-dimensional supergravity so that it behaves asymptotically as a 10-dimensional vacuum plane wave times a real line. (author)
Two-transitive MInkowski planes
Wilbrink, H.A.
1982-01-01
In this paper we determine all finite Minkowski planes with an automorphism group which satisfies the following transitivity property: any ordered pair of nonparallel points can be mapped onto any other ordered pair of nonparallel points.
Error Analysis on Plane-to-Plane Linear Approximate Coordinate ...
Indian Academy of Sciences (India)
Abstract. In this paper, the error analysis has been done for the linear approximate transformation between two tangent planes in celestial sphere in a simple case. The results demonstrate that the error from the linear transformation does not meet the requirement of high-precision astrometry under some conditions, so the ...
International Nuclear Information System (INIS)
Merriam, J.D.
1988-01-01
Problems associated with the testing of focal plane arrays are briefly examined with reference to the instrumentation and measurement procedures. In particular, the approach and instrumentation used as the Naval Ocean Systems Center is presented. Most of the measurements are made with flooded illumination on the focal plane array. The array is treated as an ensemble of individual pixels, data being taken on each pixel and array averages and standard deviations computed for the entire array. Data maps are generated, showing the pixel data in the proper spatial position on the array and the array statistics
Interaction of gravitational plane waves
International Nuclear Information System (INIS)
Ferrari, V.
1988-01-01
The mathematical theory of colliding, infinite-fronted, plane gravitational waves is presented. The process of focusing, the creation of singularities and horizons, due to the interaction, and the lens effect due to a beam-like gravitational wave are discussed
DEFF Research Database (Denmark)
Rathkjen, Arne
A state of plane stress is illustrated by means of two families of curves, each family representing constant values of a derivative of Airy's stress function. The two families of curves form a map giving in the first place an overall picture of regions of high and low stress, and in the second...
Blocking sets in Desarguesian planes
Blokhuis, A.; Miklós, D.; Sós, V.T.; Szönyi, T.
1996-01-01
We survey recent results concerning the size of blocking sets in desarguesian projective and affine planes, and implications of these results and the technique to prove them, to related problemis, such as the size of maximal partial spreads, small complete arcs, small strong representative systems
Gravitational Couplings for y-Gop-Planes
Giraldo, Juan Fernando Ospina
2000-01-01
The Wess-Zumino action for y deformed and generalized orientifold planes (yGOp-planes) is presented and one power expantion is realized from which processes that involves yGOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally non-standard yGOp-planes are showed.
Gravitational Couplings for Generalized Orientifold Planes
Giraldo, Juan Fernando Ospina
2000-01-01
The Wess-Zumino action for generalized orientifold planes (GOp-planes) is presented and a series power expantion is realized from which processes that involves GOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally non-standard GOp-planes are showed.
Hydrodynamics of planing monohull watercraft
Vorus, William S
2017-01-01
This book addresses the principles involved in the design and engineering of planing monohull power boats, with an emphasis on the theoretical fundamentals that readers need in order to be fully functional in marine design and engineering. Author William Vorus focuses on three topics: boat resistance, seaway response, and propulsion and explains the physical principles, mathematical details, and theoretical details that support physical understanding. In particular, he explains the approximations and simplifications in mathematics that lead to success in the applications of planing craft design engineering, and begins with the simplest configuration that embodies the basic physics. He leads readers, step-by-step, through the physical complications that occur, leading to a useful working knowledge of marine design and engineering. Included in the book are a wealth of examples that exemplify some of the most important naval architecture and marine engineering problems that challenge many of today’s engineers.
Plane waves with weak singularities
International Nuclear Information System (INIS)
David, Justin R.
2003-03-01
We study a class of time dependent solutions of the vacuum Einstein equations which are plane waves with weak null singularities. This singularity is weak in the sense that though the tidal forces diverge at the singularity, the rate of divergence is such that the distortion suffered by a freely falling observer remains finite. Among such weak singular plane waves there is a sub-class which does not exhibit large back reaction in the presence of test scalar probes. String propagation in these backgrounds is smooth and there is a natural way to continue the metric beyond the singularity. This continued metric admits string propagation without the string becoming infinitely excited. We construct a one parameter family of smooth metrics which are at a finite distance in the space of metrics from the extended metric and a well defined operator in the string sigma model which resolves the singularity. (author)
Functional Aesthetic Occlusal Plane (FAOP)
Câmara, Carlos Alexandre; Martins, Renato Parsekian
2016-01-01
ABSTRACT Introduction: A reasonable exposure of incisors and gingival tissues is generally considered more attractive than excess or lack of exposure. A reasonable gingival exposure is considered to be around 0 to 2 mm when smiling and 2-4 mm exposure of the maxillary incisor edge when the lips are at rest. Objective: The aim of this paper is to present the Functional Aesthetic Occlusal Plane (FAOP), which aims to help in the diagnosis of the relationships established among molars, incisors...
Plane waves and spacelike infinity
International Nuclear Information System (INIS)
Marolf, Donald; Ross, Simon F
2003-01-01
In an earlier paper, we showed that the causal boundary of any homogeneous plane wave satisfying the null convergence condition consists of a single null curve. In Einstein-Hilbert gravity, this would include any homogeneous plane wave satisfying the weak null energy condition. For conformally flat plane waves such as the Penrose limit of AdS 5 x S 5 , all spacelike curves that reach infinity also end on this boundary and the completion is Hausdorff. However, the more generic case (including, e.g., the Penrose limits of AdS 4 x S 7 and AdS 7 x S 4 ) is more complicated. In one natural topology, not all spacelike curves have limit points in the causal completion, indicating the need to introduce additional points at 'spacelike infinity' - the endpoints of spacelike curves. We classify the distinct ways in which spacelike curves can approach infinity, finding a two-dimensional set of distinct limits. The dimensionality of the set of points at spacelike infinity is not, however, fixed from this argument. In an alternative topology, the causal completion is already compact, but the completion is non-Hausdorff
Some Considerations Regarding Plane to Plane Parallelism Error Effects in Robotic Systems
Directory of Open Access Journals (Sweden)
Stelian Alaci
2015-06-01
Full Text Available The paper shows that by imposing the parallelism constraint between the measured plane and the reference plane, the position of the current plane is not univocal specified and is impossible to specify the way to attain the parallelism errors imposed by accuracy constrains. The parameters involved in the calculus of plane to plane parallelism error can be used to set univocal the relative position between the two planes.
Work Planing Automation at Mechanical Subdivision
Dzindzelėta, Vytautas
2005-01-01
Work planing automation, installation possibilities and future outlook at mechanical subdivision. To study how the work planing has changed before and after automation process and to analyse automation process methodology.
Combinatorial geometry in the plane
Hadwiger, Hugo; Klee, Victor
2014-01-01
Geared toward advanced undergraduates familiar with analysis and college geometry, this concise book discusses theorems on topics restricted to the plane such as convexity, coverings, and graphs. In addition to helping students cultivate rigorous thought, the text encourages the development of mathematical intuition and clarifies the nature of mathematical research.The two-part treatment begins with specific topics including integral distances, covering problems, point set geometry and convexity, simple paradoxes involving point sets, and pure combinatorics, among other subjects. The second pa
SNAP Satellite Focal Plane Development
International Nuclear Information System (INIS)
Bebek, C.; Akerlof, C.; Aldering, G.; Amanullah, R.; Astier, P.; Baltay, C.; Barrelet, E.; Basa, S.; Bercovitz, J.; Bergstrom, L.; Berstein, G.P.; Bester, M.; Bohlin, R.; Bonissent, A.; Bower, C.; Campbell, M.; Carithers, W.; Commins, E.; Day, C.; Deustua, S.; DiGennaro, R.; Ealet, A.; Ellis, R.; Emmett, W.; Eriksson, M.; Fouchez, D.; Fruchter, A.; Genat, J-F.; Goldhaber, G.; Goobar, A.; Groom, D.; Heetderks, H.; Holland, S.; Huterer, D.; Johnson, W.; Kadel, R.; Karcher, A.; Kim, A.; Kolbe, W.; Lafever, R.; Lamoureaux, J.; Lampton, M.; Lefevre, O.; Levi, M.; Levin, D.; Linder, E.; Loken, S.; Malina, R.; Mazure, A.; McKay, T.; McKee, S.; Miquel, R.; Morgan, N.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Roe, N.; Nugent, P.; Oluseyi, H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Prieto, E.; Rabinowitz, D.; Refregier, A.; Rhodes, J.; Schubnell, M.; Sholl, M.; Smadja, G.; Smith, R.; Smoot, G.; Snyder, J.; Spadafora, A.; Szymkowiak, A.; Tarle, G.; Taylor, K.; Tilquin, A.; Tomasch, A.; Vincent, D.; von der Lippe, H.; Walder, J-P.; Wang, G.
2003-01-01
The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square degree field in the visible and near-infrared wavelength regime. The requirements for the instrument suite and the present configuration of the focal plane concept are presented. A two year R and D phase, largely supported by the Department of Energy, is just beginning. We describe the development activities that are taking place to advance our preparedness for mission proposal in the areas of detectors and electronics
An introduction to finite projective planes
Albert, Abraham Adrian
2015-01-01
Geared toward both beginning and advanced undergraduate and graduate students, this self-contained treatment offers an elementary approach to finite projective planes. Following a review of the basics of projective geometry, the text examines finite planes, field planes, and coordinates in an arbitrary plane. Additional topics include central collineations and the little Desargues' property, the fundamental theorem, and examples of finite non-Desarguesian planes.Virtually no knowledge or sophistication on the part of the student is assumed, and every algebraic system that arises is defined and
Systems considerations in mosaic focal planes
White, K. P., III
1983-08-01
Two key reasons for pursuing the development of mosaic focal planes are reviewed and it is shown that rapid frame repetition rate is the only requirement that can be solved no other way than through mosaic focal planes. With the view that spaceborne mosaic focal plane sensors are necessarily 'smart sensors' requiring a lot of onboard processing just to function, it is pointed out that various artificial intelligence techniques may be the most appropriate to incorporate in the data processing. Finally, a novel mosaic focal plane design is proposed, termed a virtual mosaic focal plane, in response to other system constraints.
A Collaborative Knowledge Plane for Autonomic Networks
Mbaye, Maïssa; Krief, Francine
Autonomic networking aims to give network components self-managing capabilities. Several autonomic architectures have been proposed. Each of these architectures includes sort of a knowledge plane which is very important to mimic an autonomic behavior. Knowledge plane has a central role for self-functions by providing suitable knowledge to equipment and needs to learn new strategies for more accuracy.However, defining knowledge plane's architecture is still a challenge for researchers. Specially, defining the way cognitive supports interact each other in knowledge plane and implementing them. Decision making process depends on these interactions between reasoning and learning parts of knowledge plane. In this paper we propose a knowledge plane's architecture based on machine learning (inductive logic programming) paradigm and situated view to deal with distributed environment. This architecture is focused on two self-functions that include all other self-functions: self-adaptation and self-organization. Study cases are given and implemented.
Radioactivity in the galactic plane
Walraven, G. D.; Haymes, R. C.
1976-01-01
The paper reports the detection of a large concentration of interstellar radioactivity during balloon-altitude measurements of gamma-ray energy spectra in the band between 0.02 and 12.27 MeV from galactic and extragalactic sources. Enhanced counting rates were observed in three directions towards the plane of the Galaxy; a power-law energy spectrum is computed for one of these directions (designated B 10). A large statistical deviation from the power law in a 1.0-FWHM interval centered near 1.16 MeV is discussed, and the existence of a nuclear gamma-ray line at 1.15 MeV in B 10 is postulated. It is suggested that Ca-44, which emits gamma radiation at 1.156 MeV following the decay of radioactive Sc-44, is a likely candidate for this line, noting that Sc-44 arises from Ti-44 according to explosive models of supernova nucleosynthesis. The 1.16-MeV line flux inferred from the present data is shown to equal the predicted flux for a supernova at a distance of approximately 3 kpc and an age not exceeding about 100 years.
Compact planes, mostly 8-dimensional. A retrospect
Salzmann, Helmut R.
2014-01-01
Results on $8$-dimensional topological planes are scattered in the literature. It is the aim of the present paper to give a survey of these geometries, in particular of information obtained after the appearance of the treatise Compact Projective Planes or not included in this book. For some theorems new proofs are given and a few related results concerning planes of other dimensions are presented.
Nanostructured carbon films with oriented graphitic planes
International Nuclear Information System (INIS)
Teo, E. H. T.; Kalish, R.; Kulik, J.; Kauffmann, Y.; Lifshitz, Y.
2011-01-01
Nanostructured carbon films with oriented graphitic planes can be deposited by applying energetic carbon bombardment. The present work shows the possibility of structuring graphitic planes perpendicular to the substrate in following two distinct ways: (i) applying sufficiently large carbon energies for deposition at room temperature (E>10 keV), (ii) utilizing much lower energies for deposition at elevated substrate temperatures (T>200 deg. C). High resolution transmission electron microscopy is used to probe the graphitic planes. The alignment achieved at elevated temperatures does not depend on the deposition angle. The data provides insight into the mechanisms leading to the growth of oriented graphitic planes under different conditions.
Lower incisor inclination regarding different reference planes.
Zataráin, Brenda; Avila, Josué; Moyaho, Angeles; Carrasco, Rosendo; Velasco, Carmen
2016-09-01
The purpose of this study was to assess the degree of lower incisor inclination with respect to different reference planes. It was an observational, analytical, longitudinal, prospective study conducted on 100 lateral cephalograms which were corrected according to the photograph in natural head position in order to draw the true vertical plane (TVP). The incisor mandibular plane angle (IMPA) was compensated to eliminate the variation of the mandibular plane growth type with the formula "FMApx.- 25 (FMA) + IMPApx. = compensated IMPA (IMPACOM)". As the data followed normal distribution determined by the KolmogorovSmirnov test, parametric tests were used for the statistical analysis, Ttest, ANOVA and Pearson coefficient correlation test. Statistical analysis was performed using a statistical significance of p planes. There were statistically significant differences among the means of the planes measured, except for IMPACOM, FMIA and TVP. The IMPA differed significantly from the IMPACOM. The compensated IMPA and the FMIA did not differ significantly from the TVP. The true horizontal plane was mismatched with Frankfort plane in 84% of the sample with a range of 19°. The true vertical plane is adequate for measuring lower incisor inclination. Sociedad Argentina de Investigación Odontológica.
Flux dynamics in ultrasensitive superconducting focal planes
National Aeronautics and Space Administration — The performance of superconducting focal planes will drive the achievable specifications of ultrasensitive instruments for NASA astrophysics missions, yet they have...
International Nuclear Information System (INIS)
Yurtsever, U.
1988-01-01
It is well known that when two precisely plane-symmetric gravitational waves propagating in an otherwise flat background collide, they focus each other so strongly as to produce a curvature singularity. This paper is the first of several devoted to almost-plane gravitational waves and their collisions. Such waves are more realistic than plane waves in having a finite but very large transverse size. In this paper we review some crucial features of the well-known exact solutions for colliding plane waves and we argue that one of these features, the breakdown of ''local inextendibility'' can be regarded as nongeneric. We then introduce a new framework for analyzing general colliding plane-wave spacetimes; we give an alternative proof of a theorem due to Tipler implying the existence of singularities in all generic colliding plane-wave solutions; and we discuss the fact that the recently constructed Chandrasekhar-Xanthopoulos colliding plane-wave solutions are not strictly plane symmetric and thus do not satisfy the conditions and the conclusion of Tipler's theorem
Discretization of superintegrable systems on a plane
Kabát, Z.
2012-02-01
We construct difference analogues of so called Smorodinsky-Winternitz superintegrable systems in the Euclidean plane. Using methods of umbral calculus, we obtain difference equations for generalized isotropic harmonic oscillator on the uniform lattice, and also its solution in terms of power series. In the case of gauge-rotated Hamiltonian, the solution is a polynomial, well-defined in the whole plane.
Slipping and Rolling on an Inclined Plane
Aghamohammadi, Cina; Aghamohammadi, Amir
2011-01-01
In the first part of the paper, using a direct calculation two-dimensional motion of a particle sliding on an inclined plane is investigated for general values of friction coefficient ([mu]). A parametric equation for the trajectory of the particle is also obtained. In the second part of the paper, the motion of a sphere on the inclined plane is…
Moving vertices to make drawings plane
Goaoc, X.; Kratochvil, J.; Okamoto, Y.; Shin, C.S.; Wolff, A.; Hong, S.K.; Nishizeki, T.; Quan, W.
2008-01-01
In John Tantalo’s on-line game Planarity the player is given a non-plane straight-line drawing of a planar graph. The aim is to make the drawing plane as quickly as possible by moving vertices. In this paper we investigate the related problem MinMovedVertices which asks for the minimum number of
Open Cluster Dynamics via Fundamental Plane
Lin, Chien-Cheng; Pang, Xiao-Ying
2018-04-01
Open clusters (OCs) are important objects for stellar dynamics studies. The short survival timescale of OCs makes them closely related to the formation of Galactic field stars. We motivate to investigate the dynamical evolution of OCs on the aspect of internal effect and the external influence. Firstly, we make use of the known OC catalog to obtain OCs masses, effective radii. Additionally, we estimate OCs kinematics properties by OC members cross-matched with radial velocity and metallicity from SDSSIV/APOGEE2. We then establish the fundamental plane of OCs based on the radial velocity dispersion, the effective radius, and average surface brightness. The deviation of the fundamental plane from the Virial Plane, so called the tilt, and the r.m.s. dispersion of OCs around the average plane are used to indicate the dynamical status of OCs. Parameters of the fitted plane will vary with cluster age and distance.
Slipping and rolling on an inclined plane
International Nuclear Information System (INIS)
Aghamohammadi, Cina; Aghamohammadi, Amir
2011-01-01
In the first part of the paper, using a direct calculation two-dimensional motion of a particle sliding on an inclined plane is investigated for general values of friction coefficient (μ). A parametric equation for the trajectory of the particle is also obtained. In the second part of the paper, the motion of a sphere on the inclined plane is studied. It is shown that the evolution equation for the contact point of a sliding sphere is similar to that of a point particle sliding on an inclined plane whose friction coefficient is 7/2 μ. If μ > 2/7 tan θ, for any arbitrary initial velocity and angular velocity, the sphere will roll on the inclined plane after some finite time. In other cases, it will slip on the inclined plane. In the case of rolling, the centre of the sphere moves on a parabola. Finally the velocity and angular velocity of the sphere are exactly computed.
Coherent field propagation between tilted planes.
Stock, Johannes; Worku, Norman Girma; Gross, Herbert
2017-10-01
Propagating electromagnetic light fields between nonparallel planes is of special importance, e.g., within the design of novel computer-generated holograms or the simulation of optical systems. In contrast to the extensively discussed evaluation between parallel planes, the diffraction-based propagation of light onto a tilted plane is more burdensome, since discrete fast Fourier transforms cannot be applied directly. In this work, we propose a quasi-fast algorithm (O(N 3 log N)) that deals with this problem. Based on a proper decomposition into three rotations, the vectorial field distribution is calculated on a tilted plane using the spectrum of plane waves. The algorithm works on equidistant grids, so neither nonuniform Fourier transforms nor an explicit complex interpolation is necessary. The proposed algorithm is discussed in detail and applied to several examples of practical interest.
Study the Z-Plane Strip Capacitance
International Nuclear Information System (INIS)
Parikh, H.; Swain, S.
2005-01-01
The BaBaR detector at the Stanford Linear Accelerator Center is currently undergoing an upgrade to improve its muon and neutral hadron detection system. The Resistive Plate Chambers (RPCs) that had been used till now have deteriorated in performance over the past few years and are being replaced by Limited Streamer Tube (LSTs). Each layer of the system consists of a set of up to 10 streamer tube modules which provide one coordinate (φ coordinate) and a single ''Z-plane'' which provides the Z coordinate of the hit. The large area Z-planes (up to 12m 2 ) are 1mm thick and contain 96 copper strips that detect the induced charge from avalanches created in the streamer tube wires. All the Z-planes needed for the upgrade have already been constructed, but only a third of the planes were installed last summer. After installing the 24 Z-planes last year, it was learned that 0.7% of the strips were dead when put inside the detector. This was mainly due to the delicate solder joint between the read-out cable and the strip, and since it is difficult to access or replace the Z-planes inside the detector, it is very important to perform various tests to make sure that the Z-planes will be efficient and effective in the long term. We measure the capacitance between the copper strips and the ground plane, and compare it to the theoretical value that we expect. Instead of measuring the capacitance channel by channel, which would be a very tedious job, we developed a more effective method of measuring the capacitance. Since all the Z-planes were built at SLAC, we also built a smaller 46 cm by 30 cm Z-plane with 12 strips just to see how they were constructed and to gain a better understanding about the solder joints
Slip patterns and preferred dislocation boundary planes
DEFF Research Database (Denmark)
Winther, G.
2003-01-01
The planes of deformation induced extended planar dislocation boundaries are analysed in two different co-ordinate systems, namely the macroscopic system defined by the deformation axes and the crystallographic system given by the crystallographic lattice. The analysis covers single and polycryst......The planes of deformation induced extended planar dislocation boundaries are analysed in two different co-ordinate systems, namely the macroscopic system defined by the deformation axes and the crystallographic system given by the crystallographic lattice. The analysis covers single...... and polycrystals of fcc metals in three deformation modes (rolling, tension and torsion). In the macroscopic system, boundaries lie close to the macroscopically most stressed planes. In the crystallographic system, the boundary plane depends on the grain/crystal orientation. The boundary planes in both co......-ordinate systems are rationalised based on the slip. The more the slip is concentrated on a slip plane, the closer the boundaries lie to this. The macroscopic preference arises from the macroscopic directionality of the slip. The established relations are applied to (a) prediction of boundary planes from slip...
In-plane and cross-plane thermal conductivities of molybdenum disulfide
International Nuclear Information System (INIS)
Ding, Zhiwei; Pei, Qing-Xiang; Zhang, Yong-Wei; Jiang, Jin-Wu
2015-01-01
We investigate the in-plane and cross-plane thermal conductivities of molybdenum disulfide (MoS 2 ) using non-equilibrium molecular dynamics simulations. We find that the in-plane thermal conductivity of monolayer MoS 2 is about 19.76 W mK −1 . Interestingly, the in-plane thermal conductivity of multilayer MoS 2 is insensitive to the number of layers, which is in strong contrast to the in-plane thermal conductivity of graphene where the interlayer interaction strongly affects the in-plane thermal conductivity. This layer number insensitivity is attributable to the finite energy gap in the phonon spectrum of MoS 2 , which makes the phonon–phonon scattering channel almost unchanged with increasing layer number. For the cross-plane thermal transport, we find that the cross-plane thermal conductivity of multilayer MoS 2 can be effectively tuned by applying cross-plane strain. More specifically, a 10% cross-plane compressive strain can enhance the thermal conductivity by a factor of 10, while a 5% cross-plane tensile strain can reduce the thermal conductivity by 90%. Our findings are important for thermal management in MoS 2 based nanodevices and for thermoelectric applications of MoS 2 . (paper)
Yosano, Akira; Katakura, Akira; Takaki, Takashi; Shibahara, Takahiko
2009-05-01
In this study, we investigated how method of mandibular fixation influenced longterm postoperative stability of the maxilla in Class III cases. In particular, we investigated change in the maxillary occlusal plane after Occlusal Plane Alteration. Therefore, we focused on change in the palatal plane to evaluate stability of the maxillary occlusal plane, as the position of the palatal plane affects the maxillary occlusal plane. This study included 16 patients diagnosed with mandibular protrusion. Alteration of the occlusal plane was achieved by clockwise rotation of the maxilla by Le Fort I osteotomy and mandibular setback was performed by bilateral sagittal split ramus osteotomy. We analyzed and examined lateral cephalometric radiographs taken at 1 month, 3 months, 6 months, and 1 year after surgery. Stability achieved by two methods of mandibular fixation was compared. In one group of patients (group S) titanium screws were used, and in the other group (group P) titanium-locking mini-plates were used. No significant displacement was recognized in group S, whereas an approximately 0.7mm upward vertical displacement was recognized in the anterior nasal spine in group P. As a result, not only the angle of the palatal plane and S-N plane, but also occlusal plane angle in group P showed a greater decrease than that in group S. The results suggest that fixing the mandible with screws yielded greater stability of the maxilla and maxillary occlusal plane than fixing the mandible with titanium plates.
Streptococcus anginosus infections: crossing tissue planes.
Sunwoo, Bernie Y; Miller, Wallace T
2014-10-01
Streptococcus anginosus has long been recognized to cause invasive pyogenic infections. This holds true for thoracic infections where S. anginosus has a propensity for abscess and empyema formation. Early diagnosis is important given the significant morbidity and mortality associated with thoracic S. anginosus infections. Yet, distinguishing thoracic S. anginosus clinically is difficult. We present three cases of thoracic S. anginosus that demonstrated radiographic extension across tissue planes, including the interlobar fissure, diaphragm, and chest wall. Few infectious etiologies are known to cross tissue planes. Accordingly, we propose S. anginosus be considered among the differential diagnosis of potential infectious etiologies causing radiographic extension across tissue planes.
Optically sectioned imaging by oblique plane microscopy
Kumar, Sunil; Lin, Ziduo; Lyon, Alex R.; MacLeod, Ken T.; Dunsby, Chris
2011-03-01
Oblique Plane Microscopy (OPM) is a light sheet microscopy technique that combines oblique illumination with correction optics that tilt the focal plane of the collection system. OPM can be used to image conventionally mounted specimens on coverslips or tissue culture dishes and has low out-of-plane photobleaching and phototoxicity. No moving parts are required to achieve an optically sectioned image and so high speed optically sectioned imaging is possible. The first OPM results obtained using a high NA water immersion lens on a commercially available inverted microscope frame are presented, together with a measurement of the achievable optical resolution.
Causal inheritance in plane wave quotients
International Nuclear Information System (INIS)
Hubeny, Veronika E.; Rangamani, Mukund; Ross, Simon F.
2003-01-01
We investigate the appearance of closed timelike curves in quotients of plane waves along spacelike isometries. First we formulate a necessary and sufficient condition for a quotient of a general spacetime to preserve stable causality. We explicitly show that the plane waves are stably causal; in passing, we observe that some pp-waves are not even distinguishing. We then consider the classification of all quotients of the maximally supersymmetric ten-dimensional plane wave under a spacelike isometry, and show that the quotient will lead to closed timelike curves iff the isometry involves a translation along the u direction. The appearance of these closed timelike curves is thus connected to the special properties of the light cones in plane wave spacetimes. We show that all other quotients preserve stable causality
Lieb's correlation inequality for plane rotors
International Nuclear Information System (INIS)
Rivasseau, V.
1980-01-01
We prove a conjecture by E. Lieb, which leads to the Lieb inequality for plane rotors. As in the Ising model case, this inequality implies the existence of an algorithm to compute the transition temperature of this model. (orig.)
Titanium Heat Pipe Thermal Plane, Phase II
National Aeronautics and Space Administration — The objective of the Phase II program is to complete the development of the titanium heat pipe thermal plane and establish all necessary steps for production of this...
Null-plane quantization of fermions
International Nuclear Information System (INIS)
Mustaki, D.
1990-01-01
Massive Dirac fermions are canonically quantized on the null plane using the Dirac-Bergmann algorithm. The procedure is carried out in the framework of quantum electrodynamics as an illustration of a rigorous treatment of interacting fermion fields
Some Features of the Plane Couette Flow
National Research Council Canada - National Science Library
Skovorodko, Petr
2000-01-01
In the previous paper 1 it was found, in particular, that in the transition regime of the plane Couette flow the values of total energy flux and shear stress may exceed the corresponding free molecular values...
Causal inheritance in plane wave quotients
Hubeny, Veronika E.; Rangamani, Mukund; Ross, Simon F.
2004-01-01
We investigate the appearance of closed timelike curves in quotients of plane waves along spacelike isometries. First we formulate a necessary and sufficient condition for a quotient of a general space-time to preserve stable causality. We explicitly show that the plane waves are stably causal; in passing, we observe that some pp waves are not even distinguishing. We then consider the classification of all quotients of the maximally supersymmetric ten-dimensional plane wave under a spacelike isometry, and show that the quotient will lead to closed timelike curves iff the isometry involves a translation along the u direction. The appearance of these closed timelike curves is thus connected to the special properties of the light cones in plane wave space-times. We show that all other quotients preserve stable causality.
Proof of Polyakov conjecture on supercomplex plane
International Nuclear Information System (INIS)
Kachkachi, M.; Kouadik, S.
1994-10-01
Using Neumann series, we solve iteratively SBE to arbitrary order. Then applying this, we compute the energy momentum tensor and n points functions for generic n starting from WZP action on the supercomplex plane. We solve the superconformal Ward identity and we show that the iterative solution to arbitrary order is resumed by WZP action. This proves the Polyakov conjecture on supercomplex plane. (author). 8 refs
Constructive curves in non-Euclidean planes
Horváth, Ákos G.
2016-01-01
In this paper we overview the theory of conics and roulettes in four non-Euclidean planes. We collect the literature about these classical concepts, from the eighteenth century to the present, including papers available only on arXiv. The comparison of the four non-Euclidean planes, in terms of the known results on conics and roulettes, reflects only the very subjective view of the author.
Heteroepitaxial growth of basal plane stacking fault free a-plane GaN
Energy Technology Data Exchange (ETDEWEB)
Wieneke, Matthias; Hempel, Thomas; Noltemeyer, Martin; Witte, Hartmut; Dadgar, Armin; Blaesing, Juergen; Christen, Juergen; Krost, Alois [Otto-von-Guericke Universitaet Magdeburg, FNW/IEP, Magdeburg (Germany)
2010-07-01
Growth of light emitting quantum-wells based on a-plane GaN is a possibility to reduce or even to avoid polarization correlated luminescence red shift and reduction of radiative recombination efficiency. But until now heteroepitaxially grown a-plane GaN films are characterized by a poor crystalline quality expressed by a high density of basal plane stacking faults (BSF) and partial dislocations. We present Si doped a-plane GaN films grown on r-plane sapphire substrates by metal organic vapor phase epitaxy using high temperature AlGaN nucleation layers. FE-SEM images revealed three dimensionally grown GaN crystallites sized up to tenth micrometer in the basal plane and a few tenth micrometers along the c-axes. Though, the full width at half maxima of the X-ray diffraction {omega}-scans of the in-plane GaN(1 anti 100) and GaN(0002) Bragg reflections exhibited a very high crystal quality. Furthermore, luminescence spectra were dominated by near band gap emission, while there was no separated peak of the basal plane stacking fault. In summary we present heteroepitaxially grown a-plane GaN without an evidence of basal plane stacking faults in X-ray diffraction measurements and luminescence spectra.
Piracha, Mohammad M; Thorp, Stephen L; Puttanniah, Vinay; Gulati, Amitabh
Postmastectomy pain syndrome (PMPS) is a significant burden for breast cancer survivors. Although multiple therapies have been described, an evolving field of serratus anterior plane blocks has been described in this population. We describe the addition of the deep serratus anterior plane block (DSPB) for PMPS. Four patients with history of PMPS underwent DSPB for anterior chest wall pain. A retrospective review of these patients' outcomes was obtained through postprocedure interviews. Three of the patients previously had a superficial serratus anterior plane block, which was not as efficacious as the DSPB. The fourth patient had a superficial serratus anterior plane that was difficult to separate with hydrodissection but had improved pain control with a DSPB. We illustrate 4 patients who have benefitted from a DSPB and describe indications that this block may be more efficacious than a superficial serratus plane block. Further study is recommended to understand the intercostal nerve branches within the lateral and anterior muscular chest wall planes.
Affine planes, ternary rings, and examples of non-Desarguesian planes
Ivanov, Nikolai V.
2016-01-01
The paper is devoted to a detailed self-contained exposition of a part of the theory of affine planes leading to a construction of affine (or, equivalently, projective) planes not satisfying the Desarques axiom. It is intended to complement the introductory expositions of the theory of affine and projective planes. A novelty of our exposition is a new notation for the ternary operation in a ternary ring, much more suggestive than the standard one.
Deflection of electron beams by ground planes
International Nuclear Information System (INIS)
Fernsler, R.F.; Lampe, M.
1991-01-01
Analytic methods are used to determine the effect of a nearby ground plane on the trajectory of a relativistic electron beam passing through dense gas. The beam is shown to respond to the ground plane in one of two distinct modes, determined by beam current and energy. Low-power beams deflect from the ground plane and tear longitudinally. High-power beams do not deflect or tear but tilt, i.e., the beam axis is no longer parallel to the direction of propagation. This conclusion is reached by computing the net beam force as a superposition of the ''bare'' ground-plane forces, the shielding forces from the beam-generated plasma, the body coupling forces induced by beam tilt, and the force that arises as the beam separates from the plasma. Effects from electromagnetic retardation and ground resistivity are shown to be negligible in typical cases of interest, and the interaction between ground planes and other external forces is discussed as well
The horizontal plane appearances of scoliosis
DEFF Research Database (Denmark)
Illés, Tamás S.; Burkus, Máté; Somoskeőy, Szabolcs
2017-01-01
Purpose: A posterior-anterior vertebral vector is proposed to facilitate visualization and understanding of scoliosis. The aim of this study was to highlight the interest of using vertebral vectors, especially in the horizontal plane, in clinical practice. Methods: We used an EOS two-/three-dimen......Purpose: A posterior-anterior vertebral vector is proposed to facilitate visualization and understanding of scoliosis. The aim of this study was to highlight the interest of using vertebral vectors, especially in the horizontal plane, in clinical practice. Methods: We used an EOS two...... cases of a normal spine and a thoracic scoliosis are presented. Results: For a normal spine, vector projections in the transverse plane are aligned with the posterior-anterior anatomical axis. For a scoliotic spine, vector projections in the horizontal plane provide information on the lateral...... decompensation of the spine and the lateral displacement of vertebrae. In the horizontal plane view, vertebral rotation and projections of the sagittal curves can also be analyzed simultaneously. Conclusions: The use of posterior-anterior vertebral vector facilitates the understanding of the 3D nature...
A Viewpoint on the Quantity "Plane Angle"
Eder, W. E.
1982-01-01
Properties of the quantity "plane angle" are explored under the hypothesis that it is a dimensional quantity. The exploration proceeds especially with respect to the physical concept, its mathematical treatment, vector concepts, measurement theory, units of related quantities, engineering pragmatism, and SI. An attempt is made to bring these different relations into a rational, logical and consistent framework, and thus to justify the hypothesis. Various types of vectorial quantities are recognized, and their properties described with an outline of the necessary algebraic manipulations. The concept of plane angle is amplified, and its interdependence with the circular arc is explored. The resulting units of plane angle form a class of similar scales of measurement. Consequences of the confirmed hypothesis are developed for mathematical expressions involving trigonometric functions, rotational volumes and areas, mathematical limits, differentiation and series expansion. Consequences for mechanical rotational quantities are developed, with proposals for revisions to a number of expressions for derived units within SI. A revised definition for the quantity "plane angle" is stated to take account of the developed insights. There is a clear need to reconsider the status of plane angle and some other quantities within the international framework of SI.
Computed tomography of peripancreatic fat planes
International Nuclear Information System (INIS)
Wittich, G.R.; Van Sonnenberg, E.; Willson, S.A.; Tobin, R.S.; Cubberley, D.A.; Marx, M.Q.
1987-01-01
Obliteration of peripancreatic fat planes usually is considered an indicator of peripancreatic tumour infiltration in the presence of a malignant mass, or of inflammation of peripancreatic tissues in patients with pancreatitis. However, absence of peripancreatic fat planes also may be found in patients without evidence of pancreatic disease. Hence, CT scans of 125 patients without clinical or computed tomographic evidence of pancreatic disease were evaluated to assess normal variations in the anatomy of the pancreas and its relation to surrounding vessels and bowel loops. The fat plane separating the superior mesenteric artery from the pancreas was preserved in 100% of patients. Conversely, fat planes between the pancreas and the superior mesenteric vein, inferior vena cava, and adjacent bowel loops were partially or totally obliterated in 13% to 50% of patients. It is concluded that the absence of fat around the superior mesenteric artery is highly suggestive of pathologic changes of the pancreas, while the lack of fat planes between the pancreas and other splanchnic vessels or bowel loops frequently is normal, and therefore, is an unreliable sign of pancreatic disease. The applications of these findings to the assessment of tumour resectability by CT, and to CT scanning techniques, are discussed. (orig.)
On the theory of twinning plane superconductivity
International Nuclear Information System (INIS)
Mishonov, T.M.
1988-01-01
The thermodynamic potential of the superconducting layer in the twinning plane (TP) vicinity for the type I superconductors is found. The corrections to the surface tension in powers of the Ginsburg-Landau parameter κ are obtained. The corresponding states law for the supercooling field for the type I twinning plane superconductivity (TPS) is obtained, as well as the critical field law for the type II TPS. A review of experimental and theoretical works on TPS and some similar systems is given. The conditions for the Berezinski-Kosterlitz-Thouless transition for the proximity effect are discussed, as well as the possible mechanisms for the conducting phase transition TPS in Nb and the pinning forces close to the twinning plane. The obtained order parameter distribution can be used for description of the superlattices from normal and superconducting metals as well. 6 figs., 44 refs
Plane wave limits and T-duality
International Nuclear Information System (INIS)
Guven, R.
2000-04-01
The Penrose limit is generalized to show that, any leading order solution of the low-energy field equations in any one of the five string theories has a plane wave solution as a limit. This limiting procedure takes into account all the massless fields that may arise and commutes with the T-duality so that any dual solution has again a plane wave limit. The scaling rules used in the limit are unique and stem from the scaling property of the D = 11 supergravity action. Although the leading order dual solutions need not be exact or supersymmetric, their plane wave limits always preserve some portion of the Poincare supersymmetry and solve the relevant field equations in all powers of the string tension parameter. Further properties of the limiting procedure are discussed. (author)
Topologically protected edge states for out-of-plane and in-plane bulk elastic waves
Huo, Shao-Yong; Chen, Jiu-Jiu; Huang, Hong-Bo
2018-04-01
Topological phononic insulators (TPnIs) show promise for application in the manipulation of acoustic waves for the design of low-loss transmission and perfectly integrated communication devices. Since solid phononic crystals exist as a transverse polarization mode and a mixed longitudinal-transverse polarization mode, the realization of topological edge states for both out-of-plane and in-plane bulk elastic waves is desirable to enhance the controllability of the edge waves in solid systems. In this paper, a two-dimensional (2D) solid/solid hexagonal-latticed phononic system that simultaneously supports the topologically protected edge states for out-of-plane and in-plane bulk elastic waves is investigated. Firstly, two pairs of two-fold Dirac cones, respectively corresponding to the out-of-plane and in-plane waves, are obtained at the same frequency by tuning the crystal parameters. Then, a strategy of zone folding is invoked to form double Dirac cones. By shrinking and expanding the steel scatterer, the lattice symmetry is broken, and band inversions induced, giving rise to an intriguing topological phase transition. Finally, the topologically protected edge states for both out-of-plane and in-plane bulk elastic waves, which can be simultaneously located at the frequency range from 1.223 to 1.251 MHz, are numerically observed. Robust pseudospin-dependent elastic edge wave propagation along arbitrary paths is further demonstrated. Our results will significantly broaden its practical application in the engineering field.
Multiple fracture planes in deuteron irradiated metals
International Nuclear Information System (INIS)
Jones, W.R.; Johnson, P.B.
1987-01-01
Evidence has been found of multiple fracture planes in the blistering and flaking of metals observed at room temperature following irradiation at 120 K with 200 keV deuterons. In particular, two fracture planes are identified in copper, gold and stainless steel and three in aluminium. In nickel only one fracture plane is found. Qualitative models are proposed which explain the different fracture planes that are observed. In these models it is proposed that several mechanisms are important. (i) High levels of compressional stress in the implanted layer inhibits bubble nucleation and bubble growth in the depth region near the maxima in the damage and gas deposition profiles. (ii) The lateral stress varies from compression in the implant region to tension in the material below. In the region of tension bubble growth is enhanced. The vertical gradient in the lateral stress may also assist gas to move deeper into the target to further enhance bubble growth in this region. (iii) Shear resulting from differential expansion due to a combination of radiation induced swelling and localised heating is an important mechanism leading to fracture. (orig.)
Copernican Revolution in the Complex Plane
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 11. Copernican Revolution in the Complex Plane - An Algebraic Way to Show the "Chief Point" of Copernican Innovation. Giorgio Goldoni. General Article Volume 17 Issue 11 November 2012 pp 1065-1084 ...
Infrared MUSIC from Z technology focal planes
International Nuclear Information System (INIS)
Waters, C.R.; Sommese, A.; Johnston, D.; Landau, H.
1989-01-01
Presented is the Multiple Signal Classification (MUSIC) algorithm which uses the high frequency differences in sensed time signals to discriminate, count, and accurately locate closely spaced targets. Z technology focal planes allow the implementation of this algorithm and the trade-off between finer spatial resolution systems and systems with coarser resolution but higher sampling rates
Construction of the STAR Event Plane Detector
Adams, Joseph
2017-09-01
The Event Plane Detector (EPD) is an upgrade to the STAR experiment at RHIC, providing high granularity and acceptance in the forward (2.2 run for commissioning. In this talk I will discuss the construction of the EPD, the installation of the quarter wheel, and plans for full installation in 2018.
Ruler of the plane - Games of geometry
Beekhuis, S.; Buchin, K.; Castermans, T.; Hurks, T.; Sonke, W.; Aronov, B.; Katz, M.J.
2017-01-01
Ruler of the Plane is a set of games illustrating concepts from combinatorial and computational geometry. The games are based on the art gallery problem, ham-sandwich cuts, the Voronoi game, and geometric network connectivity problems like the Euclidean minimum spanning tree and traveling
Trigonometric Characterization of Some Plane Curves
Indian Academy of Sciences (India)
IAS Admin
(Figure 1). A relation between tan θ and tanψ gives the trigonometric equation of the family of curves. In this article, trigonometric equations of some known plane curves are deduced and it is shown that these equations reveal some geometric characteristics of the families of the curves under consideration. In Section 2,.
On Generalisation of Polynomials in Complex Plane
Directory of Open Access Journals (Sweden)
Maslina Darus
2010-01-01
Full Text Available The generalised Bell and Laguerre polynomials of fractional-order in complex z-plane are defined. Some properties are studied. Moreover, we proved that these polynomials are univalent solutions for second order differential equations. Also, the Laguerre-type of some special functions are introduced.
Covariant quantum mechanics on a null plane
International Nuclear Information System (INIS)
Leutwyler, H.; Stern, J.
1977-03-01
Lorentz invariance implies that the null plane wave functions factorize into a kinematical part describing the motion of the system as a whole and an inner wave function that involves the specific dynamical properties of the system - in complete correspondence with the non-relativistic situation. Covariance is equivalent to an angular condition which admits non-trivial solutions
Does monocular visual space contain planes?
Koenderink, Jan J.; Albertazzi, Liliana; van Doorn, Andrea J.; van Ee, Raymond; van de Grind, Wim A.; Kappers, Astrid M L; Lappin, Joe S.; Farley Norman, J.; (Stijn) Oomes, A. H J; te Pas, Susan P.; Phillips, Flip; Pont, Sylvia C.; Richards, Whitman A.; Todd, James T.; Verstraten, Frans A J; de Vries, Sjoerd
The issue of the existence of planes-understood as the carriers of a nexus of straight lines-in the monocular visual space of a stationary human observer has never been addressed. The most recent empirical data apply to binocular visual space and date from the 1960s (Foley, 1964). This appears to be
In-plane user positioning indoors
Jovanovic, N.; Özçelebi, T.; Lukkien, J.J.; Skoric, B.; Ignatenko, T.
2014-01-01
Indoor positioning is a service required by many smart environment applications for various purposes, such as activity classification, indoor navigation and context awareness. In this paper, we present a novel approach to the user positioning problem based on in-plane detection enabled by a set of
Techniques to measure complex-plane fields
CSIR Research Space (South Africa)
Dudley, Angela L
2014-09-25
Full Text Available In this work we construct coherent superpositions of Gaussian and vortex modes which can be described to occupy the complex-plane. We demonstrate how these fields can be experimentally constructed in a digital, controllable manner with a spatial...
Personnel thermoluminescent dosimetry of plane pilots
International Nuclear Information System (INIS)
Azorin V, J.C.; Rivera M, T.; Azorin N, J.
1999-01-01
In this work are presented the results of the research realized in the pilots of commercial planes of the different flight equipment existing. The results obtained show that the pilots receive during their work, doses of ionizing radiation greater than the limit recommended by the International Commission of Radiological Protection. (Author)
Elastic Constants of Plane Orthotropic Elasticity
DEFF Research Database (Denmark)
Krenk, Steen
1979-01-01
The four independent material parameters of plane orthotropic elasti city are introduced as the effective stiffness, the effective Poisson ratio, the stiffness ratio and the shear parameter. It is proved that stress boundary value problems with zero resulting force on internal contours lead...
Cues for localization in the horizontal plane
DEFF Research Database (Denmark)
Jeppesen, Jakob; Møller, Henrik
2005-01-01
manipulated in HRTFs used for binaural synthesis of sound in the horizontal plane. The manipulation of cues resulted in HRTFs with cues ranging from correct combinations of spectral information and ITDs to combinations with severely conflicting cues. Both the ITD and the spectral information seem...
Locating a minisum circle in the plane
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Schöbel, Anita
2009-01-01
We consider the problem of locating a circle with respect to existing facilities in the plane such that the sum of weighted distances between the circle and the facilities is minimized, i.e., we approximate a set of given points by a circle regarding the sum of weighted distances. If the radius...
Crack initiation under generalized plane strain conditions
International Nuclear Information System (INIS)
Shum, D.K.M.; Merkle, J.G.
1991-01-01
A method for estimating the decrease in crack-initiation toughness, from a reference plane strain value, due to positive straining along the crack front of a circumferential flaw in a reactor pressure vessel is presented in this study. This method relates crack initiation under generalized plane strain conditions with material failure at points within a distance of a few crack-tip-opening displacements ahead of a crack front, and involves the formulation of a micromechanical crack-initiation model. While this study is intended to address concerns regarding the effects of positive out-of- plane straining on ductile crack initiation, the approach adopted in this work can be extended in a straightforward fashion to examine conditions of macroscopic cleavage crack initiation. Provided single- parameter dominance of near-tip fields exists in the flawed structure, results from this study could be used to examine the appropriateness of applying plane strain fracture toughness to the evaluation of circumferential flaws, in particular to those in ring-forged vessels which have no longitudinal welds. In addition, results from this study could also be applied toward the analysis of the effects of thermal streaming on the fracture resistance of circumferentially oriented flaws in a pressure vessel. 37 refs., 8 figs., 1 tab
Origin of the Local Group satellite planes
Banik, Indranil; O'Ryan, David; Zhao, Hongsheng
2018-04-01
We attempt to understand the planes of satellite galaxies orbiting the Milky Way (MW) and M31 in the context of Modified Newtonian Dynamics (MOND), which implies a close MW-M31 flyby occurred ≈8 Gyr ago. Using the timing argument, we obtain MW-M31 trajectories consistent with cosmological initial conditions and present observations. We adjust the present M31 proper motion within its uncertainty in order to simulate a range of orbital geometries and closest approach distances. Treating the MW and M31 as point masses, we follow the trajectories of surrounding test particle disks, thereby mapping out the tidal debris distribution. Around each galaxy, the resulting tidal debris tends to cluster around a particular orbital pole. We find some models in which these preferred spin vectors align fairly well with those of the corresponding observed satellite planes. The radial distributions of material in the simulated satellite planes are similar to what we observe. Around the MW, our best-fitting model yields a significant fraction (0.22) of counter-rotating material, perhaps explaining why Sculptor counter-rotates within the MW satellite plane. In contrast, our model yields no counter-rotating material around M31. This is testable with proper motions of M31 satellites. In our best model, the MW disk is thickened by the flyby 7.65 Gyr ago to a root mean square height of 0.75 kpc. This is similar to the observed age and thickness of the Galactic thick disk. Thus, the MW thick disk may have formed together with the MW and M31 satellite planes during a past MW-M31 flyby.
Instability of in-plane vortices in two-dimensional easy-plane ferromagnets
International Nuclear Information System (INIS)
Wysin, G.M.
1994-01-01
An analysis of the core region of an in-plane vortex in the two-dimensional Heisenberg model with easy-plane anisotropy λ=J z /J xy leads to a clear understanding of the instability towards transformation into an out-of-plane vortex as a function of anisotropy. The anisotropy parameter λ c at which the in-plane vortex becomes unstable and develops into an out-of-plane vortex is determined with an accuracy comparable to computer simulations for square, hexagonal, and triangular lattices. For λ c , the in-plane vortex is stable but exhibits a normal mode whose frequency goes to zero as ω∝(λ c -λ) 1/2 as λ approaches λ c . For λ>λ c , the static nonzero out-of-plane spin components grow as (λ-λ c ) 1/2 . The lattice dependence of λ c is determined strongly by the number of spins in the core plaquette, is fundamentally a discreteness effect, and cannot be obtained in a continuum theory
Determining the ice-binding planes of antifreeze proteins by fluorescence-based ice plane affinity.
Basu, Koli; Garnham, Christopher P; Nishimiya, Yoshiyuki; Tsuda, Sakae; Braslavsky, Ido; Davies, Peter
2014-01-15
Antifreeze proteins (AFPs) are expressed in a variety of cold-hardy organisms to prevent or slow internal ice growth. AFPs bind to specific planes of ice through their ice-binding surfaces. Fluorescence-based ice plane affinity (FIPA) analysis is a modified technique used to determine the ice planes to which the AFPs bind. FIPA is based on the original ice-etching method for determining AFP-bound ice-planes. It produces clearer images in a shortened experimental time. In FIPA analysis, AFPs are fluorescently labeled with a chimeric tag or a covalent dye then slowly incorporated into a macroscopic single ice crystal, which has been preformed into a hemisphere and oriented to determine the a- and c-axes. The AFP-bound ice hemisphere is imaged under UV light to visualize AFP-bound planes using filters to block out nonspecific light. Fluorescent labeling of the AFPs allows real-time monitoring of AFP adsorption into ice. The labels have been found not to influence the planes to which AFPs bind. FIPA analysis also introduces the option to bind more than one differently tagged AFP on the same single ice crystal to help differentiate their binding planes. These applications of FIPA are helping to advance our understanding of how AFPs bind to ice to halt its growth and why many AFP-producing organisms express multiple AFP isoforms.
Multi-planed unified switching topologies
Chen, Dong; Heidelberger, Philip; Sugawara, Yutaka
2017-07-04
An apparatus and method for extending the scalability and improving the partitionability of networks that contain all-to-all links for transporting packet traffic from a source endpoint to a destination endpoint with low per-endpoint (per-server) cost and a small number of hops. An all-to-all wiring in the baseline topology is decomposed into smaller all-to-all components in which each smaller all-to-all connection is replaced with star topology by using global switches. Stacking multiple copies of the star topology baseline network creates a multi-planed switching topology for transporting packet traffic. Point-to-point unified stacking method using global switch wiring methods connects multiple planes of a baseline topology by using the global switches to create a large network size with a low number of hops, i.e., low network latency. Grouped unified stacking method increases the scalability (network size) of a stacked topology.
Suicide plane crash against nuclear power plants
International Nuclear Information System (INIS)
Richard, A.
2002-01-01
Cea (French atomic energy commission) and EDF (Electricity of France) are reassessing their safety standards concerning suicide plane attacks against nuclear facilities. The general idea is to study the non-linear behaviour of reinforced concrete in case of mechanical impact. American studies carried out in 1988 show that a F-14 phantom crashing into a 3,6 meter thick wall at a speed of 774 km/h penetrates only the first 5 cm of the wall. More recent studies performed in Germany and based on computerized simulations show that the reactor containment can sustain impacts from a F15 plane or even from a 747-Boeing but contiguous buildings like the one which houses spent fuels might be more easily damaged because of their metal roofing. (A.C.)
A multiplicity jump trigger using silicon planes
International Nuclear Information System (INIS)
Alexopoulos, T.; Erwin, A.R.
1993-01-01
Since silicon tracking planes are already present in a B decay experiment, it is an attractive idea to use these as part of a multiplicity jump detector. Two average B decays would produce a multiplicity jump of around 10 in the final state. Such a trigger has been tried for a fixed target Charm experiment with disappointing success. The failure was attributed to the difficulty in adequately controlling the gains of a large number of microstrip amplifies
Wafer plane inspection for advanced reticle defects
Nagpal, Rajesh; Ghadiali, Firoz; Kim, Jun; Huang, Tracy; Pang, Song
2008-05-01
Readiness of new mask defect inspection technology is one of the key enablers for insertion & transition of the next generation technology from development into production. High volume production in mask shops and wafer fabs demands a reticle inspection system with superior sensitivity complemented by a low false defect rate to ensure fast turnaround of reticle repair and defect disposition (W. Chou et al 2007). Wafer Plane Inspection (WPI) is a novel approach to mask defect inspection, complementing the high resolution inspection capabilities of the TeraScanHR defect inspection system. WPI is accomplished by using the high resolution mask images to construct a physical mask model (D. Pettibone et al 1999). This mask model is then used to create the mask image in the wafer aerial plane. A threshold model is applied to enhance the inspectability of printing defects. WPI can eliminate the mask restrictions imposed on OPC solutions by inspection tool limitations in the past. Historically, minimum image restrictions were required to avoid nuisance inspection stops and/or subsequent loss of sensitivity to defects. WPI has the potential to eliminate these limitations by moving the mask defect inspections to the wafer plane. This paper outlines Wafer Plane Inspection technology, and explores the application of this technology to advanced reticle inspection. A total of twelve representative critical layers were inspected using WPI die-to-die mode. The results from scanning these advanced reticles have shown that applying WPI with a pixel size of 90nm (WPI P90) captures all the defects of interest (DOI) with low false defect detection rates. In validating CD predictions, the delta CDs from WPI are compared against Aerial Imaging Measurement System (AIMS), where a good correlation is established between WPI and AIMSTM.
Cues for localization in the horizontal plane
DEFF Research Database (Denmark)
Jeppesen, Jakob; Møller, Henrik
2005-01-01
Spatial localization of sound is often described as unconscious evaluation of cues given by the interaural time difference (ITD) and the spectral information of the sound that reaches the two ears. Our present knowledge suggests the hypothesis that the ITD roughly determines the cone of the perce...... independently in HRTFs used for binaural synthesis. The ITD seems to be dominant for localization in the horizontal plane even when the spectral information is severely degraded....
Resonant power processors. I - State plane analysis
Oruganti, R.; Lee, F. C.
1984-01-01
State-plane techniques in conjunction with piecewise-linear analysis is employed to study the steady-state and transient characteristics of a series resonant converter. With the direct viewing of the resonant tank energy and the device switching instants, the state portrayal provides unique insights into the complex behavior of the converter. Operation of the converter under both continuous and discontinuous current modes and at frequencies both below and above resonant frequency are discussed.
The Off-plane Grating Rocket Experiment
Donovan, Benjamin
2018-01-01
The next generation of X-ray spectrometers necessitate significant increases in both resolution and effective area to achieve the science goals set forth in the 2010 Decadal Survey and the 2013 Astrophysics Roadmap. The Off-plane Grating Rocket Experiment (OGRE), an X-ray spectroscopy suborbital rocket payload currently scheduled for launch in Q3 2020, will serve as a testbed for several key technologies which can help achieve the desired performance increases of future spectrometers. OGRE will be the first instrument to fly mono-crystalline silicon X-ray mirrors developed at NASA Goddard Space Flight Center. The payload will also utilize an array of off-plane gratings manufactured at The Pennsylvania State University. Additionally, the focal plane will be populated with an array of four electron-multiplying CCDs developed by the Open University and XCAM Ltd. With these key technologies, OGRE hopes to achieve the highest resolution on-sky soft X-ray spectrum to date. We discuss the optical design, expected performance, and the current status of the payload.
Blackfolds, plane waves and minimal surfaces
Energy Technology Data Exchange (ETDEWEB)
Armas, Jay [Physique Théorique et Mathématique, Université Libre de Bruxelles and International Solvay Institutes, ULB-Campus Plaine CP231, B-1050 Brussels (Belgium); Albert Einstein Center for Fundamental Physics, University of Bern,Sidlerstrasse 5, 3012 Bern (Switzerland); Blau, Matthias [Albert Einstein Center for Fundamental Physics, University of Bern,Sidlerstrasse 5, 3012 Bern (Switzerland)
2015-07-29
Minimal surfaces in Euclidean space provide examples of possible non-compact horizon geometries and topologies in asymptotically flat space-time. On the other hand, the existence of limiting surfaces in the space-time provides a simple mechanism for making these configurations compact. Limiting surfaces appear naturally in a given space-time by making minimal surfaces rotate but they are also inherent to plane wave or de Sitter space-times in which case minimal surfaces can be static and compact. We use the blackfold approach in order to scan for possible black hole horizon geometries and topologies in asymptotically flat, plane wave and de Sitter space-times. In the process we uncover several new configurations, such as black helicoids and catenoids, some of which have an asymptotically flat counterpart. In particular, we find that the ultraspinning regime of singly-spinning Myers-Perry black holes, described in terms of the simplest minimal surface (the plane), can be obtained as a limit of a black helicoid, suggesting that these two families of black holes are connected. We also show that minimal surfaces embedded in spheres rather than Euclidean space can be used to construct static compact horizons in asymptotically de Sitter space-times.
Focal plane scanner with reciprocating spatial window
Mao, Chengye (Inventor)
2000-01-01
A focal plane scanner having a front objective lens, a spatial window for selectively passing a portion of the image therethrough, and a CCD array for receiving the passed portion of the image. All embodiments have a common feature whereby the spatial window and CCD array are mounted for simultaneous relative reciprocating movement with respect to the front objective lens, and the spatial window is mounted within the focal plane of the front objective. In a first embodiment, the spatial window is a slit and the CCD array is one-dimensional, and successive rows of the image in the focal plane of the front objective lens are passed to the CCD array by an image relay lens interposed between the slit and the CCD array. In a second embodiment, the spatial window is a slit, the CCD array is two-dimensional, and a prism-grating-prism optical spectrometer is interposed between the slit and the CCD array so as to cause the scanned row to be split into a plurality of spectral separations onto the CCD array. In a third embodiment, the CCD array is two-dimensional and the spatial window is a rectangular linear variable filter (LVF) window, so as to cause the scanned rows impinging on the LVF to be bandpass filtered into spectral components onto the CCD array through an image relay lens interposed between the LVF and the CCD array.
Blackfolds, plane waves and minimal surfaces
Armas, Jay; Blau, Matthias
2015-07-01
Minimal surfaces in Euclidean space provide examples of possible non-compact horizon geometries and topologies in asymptotically flat space-time. On the other hand, the existence of limiting surfaces in the space-time provides a simple mechanism for making these configurations compact. Limiting surfaces appear naturally in a given space-time by making minimal surfaces rotate but they are also inherent to plane wave or de Sitter space-times in which case minimal surfaces can be static and compact. We use the blackfold approach in order to scan for possible black hole horizon geometries and topologies in asymptotically flat, plane wave and de Sitter space-times. In the process we uncover several new configurations, such as black helicoids and catenoids, some of which have an asymptotically flat counterpart. In particular, we find that the ultraspinning regime of singly-spinning Myers-Perry black holes, described in terms of the simplest minimal surface (the plane), can be obtained as a limit of a black helicoid, suggesting that these two families of black holes are connected. We also show that minimal surfaces embedded in spheres rather than Euclidean space can be used to construct static compact horizons in asymptotically de Sitter space-times.
Linearized motion estimation for articulated planes.
Datta, Ankur; Sheikh, Yaser; Kanade, Takeo
2011-04-01
In this paper, we describe the explicit application of articulation constraints for estimating the motion of a system of articulated planes. We relate articulations to the relative homography between planes and show that these articulations translate into linearized equality constraints on a linear least-squares system, which can be solved efficiently using a Karush-Kuhn-Tucker system. The articulation constraints can be applied for both gradient-based and feature-based motion estimation algorithms and to illustrate this, we describe a gradient-based motion estimation algorithm for an affine camera and a feature-based motion estimation algorithm for a projective camera that explicitly enforces articulation constraints. We show that explicit application of articulation constraints leads to numerically stable estimates of motion. The simultaneous computation of motion estimates for all of the articulated planes in a scene allows us to handle scene areas where there is limited texture information and areas that leave the field of view. Our results demonstrate the wide applicability of the algorithm in a variety of challenging real-world cases such as human body tracking, motion estimation of rigid, piecewise planar scenes, and motion estimation of triangulated meshes.
Simulation Exploration through Immersive Parallel Planes: Preprint
Energy Technology Data Exchange (ETDEWEB)
Brunhart-Lupo, Nicholas; Bush, Brian W.; Gruchalla, Kenny; Smith, Steve
2016-03-01
We present a visualization-driven simulation system that tightly couples systems dynamics simulations with an immersive virtual environment to allow analysts to rapidly develop and test hypotheses in a high-dimensional parameter space. To accomplish this, we generalize the two-dimensional parallel-coordinates statistical graphic as an immersive 'parallel-planes' visualization for multivariate time series emitted by simulations running in parallel with the visualization. In contrast to traditional parallel coordinate's mapping the multivariate dimensions onto coordinate axes represented by a series of parallel lines, we map pairs of the multivariate dimensions onto a series of parallel rectangles. As in the case of parallel coordinates, each individual observation in the dataset is mapped to a polyline whose vertices coincide with its coordinate values. Regions of the rectangles can be 'brushed' to highlight and select observations of interest: a 'slider' control allows the user to filter the observations by their time coordinate. In an immersive virtual environment, users interact with the parallel planes using a joystick that can select regions on the planes, manipulate selection, and filter time. The brushing and selection actions are used to both explore existing data as well as to launch additional simulations corresponding to the visually selected portions of the input parameter space. As soon as the new simulations complete, their resulting observations are displayed in the virtual environment. This tight feedback loop between simulation and immersive analytics accelerates users' realization of insights about the simulation and its output.
Wafer plane inspection with soft resist thresholding
Hess, Carl; Shi, Rui-fang; Wihl, Mark; Xiong, Yalin; Pang, Song
2008-10-01
Wafer Plane Inspection (WPI) is an inspection mode on the KLA-Tencor TeraScaTM platform that uses the high signalto- noise ratio images from the high numerical aperture microscope, and then models the entire lithographic process to enable defect detection on the wafer plane[1]. This technology meets the needs of some advanced mask manufacturers to identify the lithographically-significant defects while ignoring the other non-lithographically-significant defects. WPI accomplishes this goal by performing defect detection based on a modeled image of how the mask features would actually print in the photoresist. There are several advantages to this approach: (1) the high fidelity of the images provide a sensitivity advantage over competing approaches; (2) the ability to perform defect detection on the wafer plane allows one to only see those defects that have a printing impact on the wafer; (3) the use of modeling on the lithographic portion of the flow enables unprecedented flexibility to support arbitrary illumination profiles, process-window inspection in unit time, and combination modes to find both printing and non-printing defects. WPI is proving to be a valuable addition to the KLA-Tencor detection algorithm suite. The modeling portion of WPI uses a single resist threshold as the final step in the processing. This has been shown to be adequate on several advanced customer layers, but is not ideal for all layers. Actual resist chemistry has complicated processes including acid and base-diffusion and quench that are not consistently well-modeled with a single resist threshold. We have considered the use of an advanced resist model for WPI, but rejected it because the burdensome requirements for the calibration of the model were not practical for reticle inspection. This paper describes an alternative approach that allows for a "soft" resist threshold to be applied that provides a more robust solution for the most challenging processes. This approach is just
Simulation Exploration through Immersive Parallel Planes
Energy Technology Data Exchange (ETDEWEB)
Brunhart-Lupo, Nicholas J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bush, Brian W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gruchalla, Kenny M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Smith, Steve [Los Alamos Visualization Associates
2017-05-25
We present a visualization-driven simulation system that tightly couples systems dynamics simulations with an immersive virtual environment to allow analysts to rapidly develop and test hypotheses in a high-dimensional parameter space. To accomplish this, we generalize the two-dimensional parallel-coordinates statistical graphic as an immersive 'parallel-planes' visualization for multivariate time series emitted by simulations running in parallel with the visualization. In contrast to traditional parallel coordinate's mapping the multivariate dimensions onto coordinate axes represented by a series of parallel lines, we map pairs of the multivariate dimensions onto a series of parallel rectangles. As in the case of parallel coordinates, each individual observation in the dataset is mapped to a polyline whose vertices coincide with its coordinate values. Regions of the rectangles can be 'brushed' to highlight and select observations of interest: a 'slider' control allows the user to filter the observations by their time coordinate. In an immersive virtual environment, users interact with the parallel planes using a joystick that can select regions on the planes, manipulate selection, and filter time. The brushing and selection actions are used to both explore existing data as well as to launch additional simulations corresponding to the visually selected portions of the input parameter space. As soon as the new simulations complete, their resulting observations are displayed in the virtual environment. This tight feedback loop between simulation and immersive analytics accelerates users' realization of insights about the simulation and its output.
ARC Code TI: X-Plane Communications Toolbox (XPC)
National Aeronautics and Space Administration — The X-Plane Communications Toolbox (XPC) is an open source research tool used to interact with the commercial flight simulator software X-Plane. XPC allows users to...
Dose distributions of pendulum fields in the field border plane
International Nuclear Information System (INIS)
Schrader, R.
1986-01-01
Calculations (program SIDOS-U2) and LiF measurements taken in a cylindric water phantom are used to investigate the isodose distributions of different pendulum irradiation methods (Co-60) in a plane which is parallel to the central ray plane and crosses the field borders at the depth of the axis. The dose values compared to the maximum values of the central ray plane are completely different for each pendulum method. In case of monoaxial pendulum methods around small angles, the maximum dose value found in the border plane is less than 50% of the dose in the central ray plane. The relative maximum of the border plane moves to tissues laying in a greater depth. In case of bi-axial methods, the maximum value of the border plane can be much more than 50% of the maximum dose measured in the central ray plane. (orig.) [de
Vacuum Predisperser For A Large Plane-Grating Spectrograph
Engleman, R.; Palmer, B. A.; Steinhaus, D. W.
1980-11-01
A plane grating predisperser has been constructed which acts as an "order-sorter" for a large plane-grating spectrograph. This combination can photograph relatively wide regions of spectra in a single exposure with no loss of resolution.
Plane wave fast color flow mode imaging
DEFF Research Database (Denmark)
Bolic, Ibrahim; Udesen, Jesper; Gran, Fredrik
2006-01-01
A new Plane wave fast color flow imaging method (PWM) has been investigated, and performance evaluation of the PWM based on experimental measurements has been made. The results show that it is possible to obtain a CFM image using only 8 echo-pulse emissions for beam to flow angles between 45...... degrees and 75 degrees. Compared to the conventional ultrasound imaging the frame rate is similar to 30 - 60 times higher. The bias, B-est of the velocity profile estimate, based on 8 pulse-echo emissions, is between 3.3% and 6.1% for beam to flow angles between 45 degrees and 75 degrees, and the standard...
Synchrotron-radiation plane-wave topography
International Nuclear Information System (INIS)
Riglet, P.; Sauvage, M.; Petroff, J.F.; Epelboin, Y.
1980-01-01
A computer program based on the Takagi-Taupin differential equations for X-ray propagation in distorted crystals has been developed in order to simulate dislocation images in the Bragg case. The program is valid both for thin and thick crystals. Simulated images of misfit dislocations formed either in a thin epilayer or in a thick substrate are compared with experimental images obtained by synchrotron-radiation plane-wave topography. The influence of the various strain components on the image features is discussed. (author)
PSB Chromaticity Correction in both Planes
Bartosik, Hannes; CERN. Geneva. ATS Department
2017-01-01
In view of the LHC injector upgrade program (LIU[1]), all LHC pre-accelerators and in particular the CERN Booster (PSB) are being reviewed for potential lattice optics and equipment optimizations. The option to correct the chromaticity in both planes would be very helpful for a better control of the beam in the presence of both non-linearities and space charge. Moreover, one could reduce decoherence phenomena that otherwise limit the usefulness of resonance measurement techniques based on a turn-by-turn BPM system.
New plastic plane stress model for concrete
International Nuclear Information System (INIS)
Winnicki, A.; Cichon, Cz.
1993-01-01
In the paper a description of concrete behaviour in the plane stress case is given on the basis of the modified bounding surface plasticity theory. Three independent plastic mechanisms have been introduced describing axiatoric and deviatoric plastic strains and their coupling. All the new analytical formulae for material functions being in agreement with experiments and loading/unloading criteria have been proposed. In addition, for the proper description of concrete behaviour in tension a new, separate function of bounding surface shrinkage has been introduced. (author)
Laurent, P.
2009-05-01
The Simbol-X focal plane is designed to detect photons focused by the mirror in the 0.5 to 100 keV energy band. Composed of two detectors, it will measure the position, energy, and arrival time of each incoming X-ray. On top of it will be a collimator to shield all photons not coming from the mirror field of view. The whole system is surrounded by an active and passive shielding in order to ensure the required very low background.
Characterization of DECam focal plane detectors
Energy Technology Data Exchange (ETDEWEB)
Diehl, H.Thomas; Angstadt, Robert; Campa, Julia; Cease, Herman; Derylo, Greg; Emes, John H.; Estrada, Juan; Kibik, Donna; Flaugher, Brenna L.; Holland, Steve E.; Jonas, Michelle; /Fermilab /Madrid, CIEMAT /LBL, Berkeley /Argonne /Pennsylvania U.
2008-06-01
DECam is a 520 Mpix, 3 square-deg FOV imager being built for the Blanco 4m Telescope at CTIO. This facility instrument will be used for the 'Dark Energy Survey' of the southern galactic cap. DECam has chosen 250 ?m thick CCDs, developed at LBNL, with good QE in the near IR for the focal plane. In this work we present the characterization of these detectors done by the DES team, and compare it to the DECam technical requirements. The results demonstrate that the detectors satisfy the needs for instrument.
The memory effect for plane gravitational waves
Zhang, P.-M.; Duval, C.; Gibbons, G. W.; Horvathy, P. A.
2017-09-01
We give an account of the gravitational memory effect in the presence of the exact plane wave solution of Einstein's vacuum equations. This allows an elementary but exact description of the soft gravitons and how their presence may be detected by observing the motion of freely falling particles. The theorem of Bondi and Pirani on caustics (for which we present a new proof) implies that the asymptotic relative velocity is constant but not zero, in contradiction with the permanent displacement claimed by Zel'dovich and Polnarev. A non-vanishing asymptotic relative velocity might be used to detect gravitational waves through the "velocity memory effect", considered by Braginsky, Thorne, Grishchuk, and Polnarev.
On Helmholtz Problem for Plane Periodical Structures
International Nuclear Information System (INIS)
Akishin, P.G.; Vinitskij, S.I.
1994-01-01
The plane Helmholtz problem of the periodical disc structures with the phase shifts conditions of the solutions along the basis lattice vectors and the Dirichlet conditions on the basic boundaries is considered. The Green function satisfying the quasi periodical conditions on the lattice is constructed. The Helmholtz problem is reduced to the boundary integral equations for the simple layer potentials of this Green function. The methods of the discretization of the arising integral equations are proposed. The procedures of calculation of the matrix elements are discussed. The reality of the spectral parameter of the nonlinear continuous and discretized problems is shown. 8 refs., 2 figs
In-plane and out-of-plane nonlinear dynamics of an axially moving beam
International Nuclear Information System (INIS)
Farokhi, Hamed; Ghayesh, Mergen H.; Amabili, Marco
2013-01-01
In the present study, the nonlinear forced dynamics of an axially moving beam is investigated numerically taking into account the in-plane and out-of-plane motions. The nonlinear partial differential equations governing the motion of the system are derived via Hamilton’s principle. The Galerkin scheme is then introduced to these partial differential equations yielding a set of second-order nonlinear ordinary differential equations with coupled terms. This set is transformed into a new set of first-order nonlinear ordinary differential equations by means of a change of variables. A direct time integration technique is conducted upon the new set of equations resulting in the bifurcation diagrams of Poincaré maps of the system. The dynamical characteristics of the system are investigated for different system parameters and presented through use of time histories, phase-plane portraits, Poincaré sections, and fast Fourier transforms
16-dimensional smooth projective planes with large collineation groups
Bödi, Richard
1998-01-01
Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch) Smooth projective planes are projective planes defined on smooth manifolds (i.e. the set of points and the set of lines are smooth manifolds) such that the geometric operations of join and intersection are smooth. A systematic study of such planes and of their collineation groups can be found in previous works of the author. We prove in this paper that a 16-dimensional smooth projective plane which admits a ...
On Finite Hjelmslev Planes of Parameters (pk−1, p)
Atilla Akpinar
2010-01-01
In this paper, we study on finite projective Hjelmslev planes M(Zq) coordinatized by Hjelmslev ring Zq (where prime power q = pk). We obtain finite hyperbolic Klingenberg planes from these planes under certain conditions. Also, we give a combinatorical result on M(Zq), related by deleting a line from lines in same neighbour.
Multispectral linear array (MLA) focal plane mechanical and thermal design
Mitchell, A. S.; Kaminski, E. F.
1982-01-01
The mechanical and thermal design of an integrated focal plane subsystem of a Multispectral Linear Array (MLA) instrument is discussed in terms of focal-plane alignment, thermoelastic performance, and thermal requirements. The modular construction and thermal control of the focal plane array are discussed.
The Curious Out-of-Plane Conductivity of PEDOT : PSS
van de Ruit, Kevin; Katsouras, Ilias; Bollen, Dirk; van Mol, Ton; Janssen, Rene A. J.; de Leeuw, Dago M.; Kemerink, Martijn
2013-01-01
For its application as transparent conductor in light-emitting diodes and photovoltaic cells, both the in-plane and out-of-plane conductivity of PEDOT:PSS are important. However, studies into the conductivity of PEDOT:PSS rarely address the out-of-plane conductivity and those that do, report widely
Fermi system with planes and charge reservoir: Anisotropic in-plane resistivity
International Nuclear Information System (INIS)
Levin, G.A.; Quader, K.F.
1992-01-01
The authors explore the normal state in-plane resistivity of a model Fermi system with two planes and a charge reservoir. When the Fermi energy lies near the top of one of the resulting sub-bands, the system can be described by two types of quasiparticle excitations with different energy spectra and relaxation times. They show that for certain stoichiometry, ρ ab is linear in temperature with positive or negative intercepts. A relation between the slopes and intercepts of resistivities in the a and b directions in untwinned crystals is derived. The results are in good agreement with experimental data on YBCO. 7 refs., 1 tab
Traces of chiral symmetry on light planes
International Nuclear Information System (INIS)
Sazdjian, Hagop.
1975-01-01
The possibility of a description of the hadronic world by field theories defined on light planes and formulated in terms of three interacting quark field variables has been investigated. The framework of models where the chiral symmetry breaking is produced by the only mechanical masses of quarks has been considered. The hypothesis that the light plane charges generate in the real world approximate symmetries of one particle states has also been emitted. The projection of the algebraic structure of the observables in the space of physical states have yielded various relations in terms of the masses and couplings of the low lying mesons. They seem to be in agreement with experimental data, and suggest the consistency of the adopted model to describe symmetry breaking phenomena. The quark mechanical masses m(u) approximately 30MeV and m(s) approximately 200MeV have also been estimated. The smallness of these masses in respect to those of hadrons seems to indicate that they do not constitute the only mass scale of the hadronic world, but that there should exist another scale parameter, independent of the quark mechanical masses, and symmetric of SU(3) [fr
The plane motion control of the quadrocopter
Directory of Open Access Journals (Sweden)
A. N. Kanatnikov
2015-01-01
Full Text Available Among a large number of modern flying vehicles, the quadrocopter relates to unmanned aerial vehicles (UAV which are relatively cheap and easy to design. Quadrocopters are able to fly in bad weather, hang in the air for quite a long time, observe the objects and perform many other tasks. They have been applied in rescue operations, in agriculture, in the military and many other fields.For quadrocopters, the problems of path planning and control are relevant. These problems have many variants in which limited resources of modern UAV, possible obstacles, for instance, for flying in a cross-country terrain or in a city environment and weather conditions (particularly, wind conditions are taken into account. Many research studies are concerned with these problems and reflected in series of publications (note the interesting survey [1] and references therein. Various methods were used for the control synthesis for these vehicles: linear approximations [2], sliding mode control [3], the covering method [4] and so on.In the paper, a quadrocopter is considered as a rigid body. The kinematic and dynamic equations of the motion are analyzed. Two cases of motion are emphasized: a motion in a vertical plane and in a horizontal plane. The control is based on transferring of the affine system to the canonical form [5] and the nonlinear stabilization method [6].
The Sentinel-4 UVN focal plane assemblies
Hinger, Jürgen; Hohn, Rüdiger; Gebhardt, Eyk; Reichardt, Jörg
2017-09-01
The Sentinel-4 UVN Instrument is a dispersive imaging spectrometer covering the UV-VIS and the NIR wavelength. It is developed and built under an ESA contract by an industrial consortium led by Airbus Defence and Space. It will be accommodated on board of the MTG-S (Meteosat Third Generation - Sounder) satellite that will be placed in a geostationary orbit over Europe sampling data for generating two-dimensional maps of a number of atmospheric trace gases. The incoming light is dispersed by reflective gratings and detected by the two (UVVIS and NIR) CCDs mounted inside the focal plane assemblies. Both CCD detectors acquire spectral channels and spatial sampling in two orthogonal directions and will be operated at about 215 K mainly to minimize random telegraph signal effects and to reduce dark current. Stringent detector temperature as well as alignment stability requirements of less than +/-0.1 K per day respectively of less than 2 micrometers/2 arcseconds from ground to orbit are driving the FPA thermo-mechanical design. A specific FPA design feature is the redundant LED-calibration system for bad pixel detection as well as pixel gain and linearity monitoring. This paper reports on the design and qualification of the Focal Plane Assemblies with emphasis on thermo-mechanical as well as alignment stability verification.
The Sentinel 4 focal plane subsystem
Hohn, Rüdiger; Skegg, Michael P.; Hermsen, Markus; Hinger, Jürgen; Williges, Christian; Reulke, Ralf
2017-09-01
The Sentinel 4 instrument is an imaging spectrometer, developed by Airbus under ESA contract in the frame of the joint European Union (EU)/ESA COPERNICUS program with the objective of monitoring trace gas concentrations. Sentinel 4 will provide accurate measurements of key atmospheric constituents such as ozone, nitrogen dioxide, sulfur dioxide, formaldehyde, as well as aerosol and cloud properties. Sentinel 4 is unique in being the first geostationary UVN mission. The SENTINEL 4 space segment will be integrated on EUMETSAT's Meteosat Third Generation Sounder satellite (MTG-S). Sentinel 4 will provide coverage of Europe and adjacent regions. The Sentinel 4 instrument comprises as a major element two Focal Plane Subsystems (FPS) covering the wavelength ranges 305 nm to 500 nm (UVVIS) and 750 nm to 775 nm (NIR) respectively. The paper describes the Focal Plane Subsystems, comprising the detectors, the optical bench and the control electronics. Further the design and development approach will be presented as well as first measurement results of FPS Qualification Model.
Mathematical Foundation for Plane Covering Using Hexagons
Johnson, Gordon G.
1999-01-01
This work is to indicate the development and mathematical underpinnings of the algorithms previously developed for covering the plane and the addressing of the elements of the covering. The algorithms are of interest in that they provides a simple systematic way of increasing or decreasing resolution, in the sense that if we have the covering in place and there is an image superimposed upon the covering, then we may view the image in a rough form or in a very detailed form with minimal effort. Such ability allows for quick searches of crude forms to determine a class in which to make a detailed search. In addition, the addressing algorithms provide an efficient way to process large data sets that have related subsets. The algorithms produced were based in part upon the work of D. Lucas "A Multiplication in N Space" which suggested a set of three vectors, any two of which would serve as a bases for the plane and also that the hexagon is the natural geometric object to be used in a covering with a suggested bases. The second portion is a refinement of the eyeball vision system, the globular viewer.
Plasma drift towards a plane equipotential surface
International Nuclear Information System (INIS)
Carlqvist, P.
1984-03-01
Recently Alfven has qualitatively described how a collisionless plasma drifts in crossed electric and magnetic fields towards an infinite conducting plate of constant potential. In the present note we quantitatively study three models which are closely related to Alfven's model. It is found that when the plasma comes sufficiently close to a plane equipotential surface (conducting plate) it is deflected approximately along the surface. The deflection is not caused by pressure effects but rather by the electric and magnetic fields. Small fluxes of ions and electrons also cross the plane equipotential surface. These fluxes account for an electric current in the plasma which induces a magnetic field in the same direction as the total magnetic field assumed to be homogeneous. It is shown that if the Alfven number, M(sub)A, is much smaller than unity in the volume considered the magnetic field induced by plasma currents is small compared to the total magnetic field. However, if M(sub)A is of the order of unity or larger the total magnetic field is to a substantial degree generated by plasma currents. (Author)
A Single-Element Plane Grating Monochromator
Directory of Open Access Journals (Sweden)
Michael C. Hettrick
2016-01-01
Full Text Available Concerted rotations of a self-focused varied line-space diffraction grating about its groove axis and surface normal define a new geometric class of monochromator. Defocusing is canceled, while the scanned wavelength is reinforced at fixed conjugate distances and horizontal deviation angle. This enables high spectral resolution over a wide band, and is of particular advantage at grazing reflection angles. A new, rigorous light-path formulation employs non-paraxial reference points to isolate the lateral ray aberrations, with those of power-sum ≤ 3 explicitly expanded for a plane grating. Each of these 14 Fermat equations agrees precisely with the value extracted from numerical raytrace simulations. An example soft X-ray design (6° deviation angle and 2 × 4 mrad aperture attains a resolving power > 25 , 000 over a three octave scan range. The proposed rotation scheme is not limited to plane surfaces or monochromators, providing a new degree of freedom in optical design.
Zafar, Junaid
2012-01-01
The geometrical relationship between the cut-off and propagating planes of any waveguide system is a prerequisite for any design process. The characterization of cut-off planes and optimisation are challenging for numerical methods, closed-form solutions are always preferred. In this paper Maxwells coupled field equations are used to characterise twin E-plane and H-plane slab loaded boundary value problems. The single mode bandwidths and dispersion characteristics of these structures are pres...
International Nuclear Information System (INIS)
Vlasov, A.A.
1988-01-01
The necessity of covariant connection of plane space metrics in the gravity theory ''on a plane background'' is underlined. It is shown that this connection in the relativistic gravity theory results in its difference from the general relativity theory ''on a plane background''
The in-focus variable line spacing plane grating monochromator
International Nuclear Information System (INIS)
Reininger, R.
2011-01-01
The in-focus variable line spacing plane grating monochromator is based on only two plane optical elements, a variable line spacing plane grating and a plane pre-mirror that illuminates the grating at the angle of incidence that will focus the required photon energy. A high throughput beamline requires only a third optical element after the exit slit, an aberration corrected elliptical toroid. Since plane elements can be manufactured with the smallest figure errors, this monochromator design can achieve very high resolving power. Furthermore, this optical design can correct the deformations induced by the heat load on the optics along the dispersion plane. This should allow obtaining a resolution of 10 meV at 1 keV with currently achievable figure errors on plane optics. The position of the photon source when an insertion device center is not located at the center of the straight section, a common occurrence in new insertion device beamlines, is investigated.
Guide-Plane Retention in Designing Removable Partial Dentures.
Mothopi-Peri, Matshediso; Owen, C Peter
To compare the influence of abutment teeth guide planes and guiding surfaces on retention of a removable partial denture (RPD). Extracted teeth embedded into a maxillary cast in the first premolar and second molar positions simulated two bounded saddles. Acrylic resin RPDs were made with no guide planes, then with guide planes, then with guiding surfaces added to directly contact the guide planes. The maximum loads on removal from the cast were recorded. There was a significant increase in retention force of 1.6 times when only guide planes were present and of 10.2 times when guiding surfaces intimately contacted the guide planes. The retention of acrylic resin RPDs can be substantially increased by making their guiding surfaces intimately contact the guide planes of the teeth.
Plane grating monochromators for synchrotron radiation
International Nuclear Information System (INIS)
Howells, M.R.
1979-01-01
The general background and theoretical basis of plane grating monochromators (PGM's) is reviewed and the particular case of grazing incidence PGM's suitable for use with synchrotron radiation is considered in detail. The theory of reflection filtering is described and the problem of the finite source distance is shown to be of special importance with high brightness storage rings. The design philosophy of previous instruments is discussed and a new scheme proposed, aimed at dealing with the problem of the finite source distance. This scheme, involving a parabolic collimating mirror fabricated by diamond turning, is considered in the context of Wolter-type telescopes and microscopes. Some practical details concerning an instrument presently under construction using the new design are presented
Drawing Contour Trees in the Plane.
Heine, C; Schneider, D; Carr, Hamish; Scheuermann, G
2011-11-01
The contour tree compactly describes scalar field topology. From the viewpoint of graph drawing, it is a tree with attributes at vertices and optionally on edges. Standard tree drawing algorithms emphasize structural properties of the tree and neglect the attributes. Applying known techniques to convey this information proves hard and sometimes even impossible. We present several adaptions of popular graph drawing approaches to the problem of contour tree drawing and evaluate them. We identify five esthetic criteria for drawing contour trees and present a novel algorithm for drawing contour trees in the plane that satisfies four of these criteria. Our implementation is fast and effective for contour tree sizes usually used in interactive systems (around 100 branches) and also produces readable pictures for larger trees, as is shown for an 800 branch example.
Landau levels on the hyperbolic plane
International Nuclear Information System (INIS)
Fakhri, H; Shariati, M
2004-01-01
The quantum states of a spinless charged particle on a hyperbolic plane in the presence of a uniform magnetic field with a generalized quantization condition are proved to be the bases of the irreducible Hilbert representation spaces of the Lie algebra u(1, 1). The dynamical symmetry group U(1, 1) with the explicit form of the Lie algebra generators is extracted. It is also shown that the energy has an infinite-fold degeneracy in each of the representation spaces which are allocated to the different values of the magnetic field strength. Based on the simultaneous shift of two parameters, it is also noted that the quantum states realize the representations of Lie algebra u(2) by shifting the magnetic field strength. (letter to the editor)
Landau levels on the hyperbolic plane
Energy Technology Data Exchange (ETDEWEB)
Fakhri, H [Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran 19395-5531 (Iran, Islamic Republic of); Shariati, M [Department of Physics, Khajeh Nassir-Al-Deen Toosi University of Technology, Tehran 15418 (Iran, Islamic Republic of)
2004-11-05
The quantum states of a spinless charged particle on a hyperbolic plane in the presence of a uniform magnetic field with a generalized quantization condition are proved to be the bases of the irreducible Hilbert representation spaces of the Lie algebra u(1, 1). The dynamical symmetry group U(1, 1) with the explicit form of the Lie algebra generators is extracted. It is also shown that the energy has an infinite-fold degeneracy in each of the representation spaces which are allocated to the different values of the magnetic field strength. Based on the simultaneous shift of two parameters, it is also noted that the quantum states realize the representations of Lie algebra u(2) by shifting the magnetic field strength. (letter to the editor)
Smart trigger logic for focal plane arrays
Levy, James E; Campbell, David V; Holmes, Michael L; Lovejoy, Robert; Wojciechowski, Kenneth; Kay, Randolph R; Cavanaugh, William S; Gurrieri, Thomas M
2014-03-25
An electronic device includes a memory configured to receive data representing light intensity values from pixels in a focal plane array and a processor that analyzes the received data to determine which light values correspond to triggered pixels, where the triggered pixels are those pixels that meet a predefined set of criteria, and determines, for each triggered pixel, a set of neighbor pixels for which light intensity values are to be stored. The electronic device also includes a buffer that temporarily stores light intensity values for at least one previously processed row of pixels, so that when a triggered pixel is identified in a current row, light intensity values for the neighbor pixels in the previously processed row and for the triggered pixel are persistently stored, as well as a data transmitter that transmits the persistently stored light intensity values for the triggered and neighbor pixels to a data receiver.
Plane shock wave studies of geologic media
International Nuclear Information System (INIS)
Anderson, G.D.; Larson, D.B.
1977-01-01
Plane shock wave experiments have been conducted on eight geologic materials in an effort to determine the importance of time-dependent mechanical behavior. Of the eight rocks studied, only Westerly granite and nugget sandstone appear to show time independence. In the slightly porous materials (1-5 percent), Blair dolomite and sodium chloride, and in the highly porous (15 to 40 percent) rock, Mt. Helen tuff and Indiana limestone, time-dependent behavior is associated with the time required to close the available porosity. In water-saturated rocks the time dependence arises because the water that is present shows no indication of transformation to the higher pressure ice phases, thus suggesting the possibility that a metastable form of water exists under dynamic conditions
A ''quadratized'' augmented plane wave method
International Nuclear Information System (INIS)
Smrcka, L.
1982-02-01
The exact radial solution inside the muffin-tin sphere is replaced by its Taylor expansion with respect to the energy, truncated after the quadratic term. Making use of it the energy independent augmented plane waves are formed which lead to the secular equations linear in energy. The method resembles the currently used linearized APW method but yields higher accuracy. The analysis of solution inside one muffin-tin sphere shows that the eigenvalue error is proportional to (E-E 0 ) 6 as compared with (E-E 0 ) 4 for LAPW. The error of eigenfunctions is (E-E 0 ) 3 ((E-E 0 ) 2 for LAPW). These conclusions are confirmed by direct numerical calculation of band structure of Cu and Al. (author)
LATCHAROTE; Panon KAI, Yoshiro
2015-01-01
A macroscopic model, macro plate model, was proposed to represent a wall member of RC walls. Both in-plane and out-of-plane behavior were considered for numerical derivations of macro plate model. For out-of-plane behavior, bending deformation was incorporated with shear deformation to consider out-of-plane deformation as same as in-plane behavior. The hysteretic behavior of macro plate model can be directly expressed by stress-strain relationships in any conventional hysteretic rules, which ...
Estimating the Value of the Inclination Angle of the Lunar Plane to the Ecliptic Plane
Isildak, R. Suat; Isik, Hakan; Küçüközer, H. Asuman
2018-01-01
Sky appears to our students as a vast volume surrounding the Earth. The most striking astronomical events that they can witness in the sky are lunar phases and eclipses. However, eclipses do not occur as often as full and new phases of the Moon. This difference is due to the fact that the orbital planes of the Moon and the Earth do not overlap.…
In-plane and out-of-plane bending tests on carbon steel pipe bends
International Nuclear Information System (INIS)
Brouard, D.; Tremblais, A.; Vrillon, B.
1979-01-01
The objectives of these tests were to obtain experimental results on bends behaviour in elastic and plastic regime by in plane and out of plane bending. Results were used to improve the computer model, for large distorsion of bends, to be used in a simplified beam type computer code for piping calculations. Tests were made on type ANSI B 169 DN 5 bends in ASTM A 106 Grade B carbon steel. These tests made it possible to measure, for identical bends, in elastic regime, the flexibility factors and, in plastic regime, the total evolution in opening, in closing and out of plane. Flexibility factors of 180 0 bend without flanges are approximately the same in opening and in closing. The end effect due to flanges is not very significant, but it is important for 90 0 bends. In plastic regime, collapse loads or collapse moments of bends depends also of both the end effects and the angle bend. The end effects and the angle bend are more sensitive in opening than in closing. The interest of these tests is to procure some precise evolution curves of identical bends well characterized in geometry and metal strength, deflected in large distorsions. (orig./HP)
First results from the INTEGRAL galactic plane scans
DEFF Research Database (Denmark)
Winkler, C.; Gehrels, N.; Schonfelder, V.
2003-01-01
Scans of the Galactic plane performed at regular intervals constitute a key element of the guaranteed time observations of the INTEGRAL observing programme. These scans are done for two reasons: frequent monitoring of the Galactic plane in order to detect transient sources, and time resolved mapp...... mapping of the Galactic plane in continuum and diffuse line emission. This paper describes first results obtained from the Galactic plane scans executed so far during the early phase (Dec. 2002-May 2003) of the nominal mission.......Scans of the Galactic plane performed at regular intervals constitute a key element of the guaranteed time observations of the INTEGRAL observing programme. These scans are done for two reasons: frequent monitoring of the Galactic plane in order to detect transient sources, and time resolved...
International Nuclear Information System (INIS)
Goncalves Filho, Orlando J.A.
2015-01-01
This work reports the progress in the development of a new experimental protocol for plane stress determination in orthotropic materials based on the ultrasonic velocity of bulk waves propagating in non symmetry planes with oblique incidence. The presence of stress-induced deformation introduces an acoustic anisotropy in the material in addition to that defined by its texture. Orthotropic materials under general plane stress states become acoustically monoclic and its orthotropic planes orthogonal to the stress plane become non symmetry planes. The inverse solution of the generalized Christoffel equation for ultrasonic bulk waves propagating in non symmetry planes of anisotropic bodies is known to be numerically unstable. The suggested protocol deals with this numerical instability without recourse to bulk wave propagation in the stress plane as proposed in the literature. Hence, it should be useful for plane stress analysis of thin wall pressure vessels where ultrasonic measurements in the direction of the wall plane are not possible. For the initial validation of the suggested protocol and verification of the stability of the inversion algorithm, computer simulation of stress determination have been performed from synthetic sets of velocity data obtained by the forward solution of the generalized Christoffel equation. Preliminary results for slightly orthotropic aluminium highlight the potential of the suggested protocol. (author)
Helical waves in easy-plane antiferromagnets
Semenov, Yuriy G.; Li, Xi-Lai; Xu, Xinyi; Kim, Ki Wook
2017-12-01
Effective spin torques can generate the Néel vector oscillations in antiferromagnets (AFMs). Here, it is theoretically shown that these torques applied at one end of a normal AFM strip can excite a helical type of spin wave in the strip whose properties are drastically different from characteristic spin waves. An analysis based on both a Néel vector dynamical equation and the micromagnetic simulation identifies the direction of magnetic anisotropy and the damping factor as the two key parameters determining the dynamics. Helical wave propagation requires the hard axis of the easy-plane AFM to be aligned with the traveling direction, while the damping limits its spatial extent. If the damping is neglected, the calculation leads to a uniform periodic domain wall structure. On the other hand, finite damping decelerates the helical wave rotation around the hard axis, ultimately causing stoppage of its propagation along the strip. With the group velocity staying close to spin-wave velocity at the wave front, the wavelength becomes correspondingly longer away from the excitation point. In a sufficiently short strip, a steady-state oscillation can be established whose frequency is controlled by the waveguide length as well as the excitation energy or torque.
Planes y proyectos para un desarrollo sustentable
Directory of Open Access Journals (Sweden)
Mg. Arq. Jorge Montenegro
2014-12-01
Full Text Available La cátedra de Urbanismo I A de la Facultad de Arquitectura, Urbanismo y Diseño de la Universidad Nacional de Córdoba, considera que es fundamental educar a los alumnos en la construcción de un pensamiento crítico reﬂexivo, sobre la base de teorías, modelos y metodologías preocupados por el desarrollo sustentable de nuestras ciudades. En este contexto, la cátedra promueve la construcción de una visión holística sobre la ciudad, abordando los contenidos, metodologías e instrumentación específca —planes maestros, proyectos urbanos— desde los enfoques tradicionales: físico–funcional y morfológico–perceptual, los que se complementan con una mirada socioambiental del fenómeno urbano. En este artículo presentamos una síntesis de la tarea académica que desarrollamos.
planes de estudio y orientaciones oficiales
Directory of Open Access Journals (Sweden)
María Eugenia Fernández Fraile
2005-01-01
Full Text Available El presente artículo se propone, a través del análisis de los cambios introducidos en los Planes de estudios que más incidencia tienen sobre la enseñanza de las lenguas vivas (1900, 1926, 1934, 1938, 1953/1957, 1970 y 1990, destacar las tendencias evolutivas o las líneas maestras que configuran el concepto del Francés como Lengua Extranjera en tanto que disciplina escolar Se abordan así, en una presentación cronológica, las siguientes cuestiones: la regulación de la materia en sus aspectos materiales (horario, cursos, el concepto social e institucional de la disciplina (en conexión con el resto de las lenguas vivas y, finalmente, los objetivos-contenidos didácticos y las orientaciones metodológicas presentes en los textos oficiales.
Grand unification in the projective plane
International Nuclear Information System (INIS)
Hebecker, A.
2004-01-01
A 6-dimensional grand unified theory with the compact space having the topology of a real projective plane, i.e., a 2-sphere with opposite points identified, is considered. The space is locally flat except for two conical singularities where the curvature is concentrated. One supersymmetry is preserved in the effective 4d theory. The unified gauge symmetry, for example SU(5), is broken only by the non-trivial global topology. In contrast to the Hosotani mechanism, no adjoint Wilson-line modulus associated with this breaking appears. Since, locally, SU(5) remains a good symmetry everywhere, no UV-sensitive threshold corrections arise and SU(5)-violating local operators are forbidden. Doublet-triplet splitting can be addressed in the context of a 6d N=2 super Yang-Mills theory with gauge group SU(6). If this symmetry is first broken to SU(5) at a fixed point and then further reduced to the standard model group in the above non-local way, the two light Higgs doublets of the MSSM are predicted by the group-theoretical and geometrical structure of the model. (author)
Hybrid inflation in the complex plane
International Nuclear Information System (INIS)
Buchmueller, W.; Domcke, V.; Kamada, K.; Schmitz, K.
2014-04-01
Supersymmetric hybrid inflation is an exquisite framework to connect inflationary cosmology to particle physics at the scale of grand unification. Ending in a phase transition associated with spontaneous symmetry breaking, it can naturally explain the generation of entropy, matter and dark matter. Coupling F-term hybrid inflation to soft supersymmetry breaking distorts the rotational invariance in the complex inflaton plane - an important fact, which has been neglected in all previous studies. Based on the δN formalism, we analyze the cosmological perturbations for the first time in the full two-field model, also taking into account the fast-roll dynamics at and after the end of inflation. As a consequence of the two-field nature of hybrid inflation, the predictions for the primordial fluctuations depend not only on the parameters of the Lagrangian, but are eventually fixed by the choice of the inflationary trajectory. Recognizing hybrid inflation as a two-field model resolves two shortcomings often times attributed to it: The fine-tuning problem of the initial conditions is greatly relaxed and a spectral index in accordance with the PLANCK data can be achieved in a large part of the parameter space without the aid of supergravity corrections. Our analysis can be easily generalized to other (including large-field) scenarios of inflation in which soft supersymmetry breaking transforms an initially single-field model into a multi-field model.
Condensation on a cooled plane upright wall
International Nuclear Information System (INIS)
Fortier, Andre.
1975-01-01
The vapor condensation along a cooled upright plane wall was studied. The theoretical and experimental results obtained in the simple case, give the essential characteristics of the phenomenon of condensation along a cold wall that keeps the vapor apart from the coolant inside a surface condenser. The phenomenon presents two different appearances according as the wall is wetted or not by the liquid. In the first case a continuous liquid film runs down the wall and a conventional Nusselt calculation gives the film thickness and the heat exchange coefficient between a pure saturated vapor and the cold wall. The calculation is developed in detail and the effect of a vapor flow along the film is discussed as well as that of the presence of a noncondensable gas inside the vapor. In the second case, separated liquid drops are formed on the wall, the phenomenon is called ''dropwise condensation'' and the heat exchange coefficients obtained are much higher than with film condensation. The theoretical aspects of the problem are discussed with some experimental results [fr
Context based Coding of Quantized Alpha Planes for Video Objects
DEFF Research Database (Denmark)
Aghito, Shankar Manuel; Forchhammer, Søren
2002-01-01
In object based video, each frame is a composition of objects that are coded separately. The composition is performed through the alpha plane that represents the transparency of the object. We present an alternative to MPEG-4 for coding of alpha planes that considers their specific properties....... Comparisons in terms of rate and distortion are provided, showing that the proposed coding scheme for still alpha planes is better than the algorithms for I-frames used in MPEG-4....
Study of combined cycle engine for aerospace plane
苅田, 丈士; KANDA, Takeshi; 工藤, 賢司; KUDO, Kenji
2002-01-01
At the Ramjet Propulsion Research Center, the scramjet engine for an aerospace plane has been studied. Other engines are required for the plane to go into orbit. Recently, a combined cycle engine including scramjet mode has been also studied to complete the engine system for the plane. The scramjet and the combined cycle engine are most effective with application to the Single-Stage-to-Orbit (SSTO) aerospace plane, as shown in Figure 1. Recent activity on the combined cycle engine and the SST...
Quantum Mechanics on the h-deformed Quantum Plane
Cho, Sunggoo
1998-01-01
We find the covariant deformed Heisenberg algebra and the Laplace-Beltrami operator on the extended $h$-deformed quantum plane and solve the Schr\\"odinger equations explicitly for some physical systems on the quantum plane. In the commutative limit the behaviour of a quantum particle on the quantum plane becomes that of the quantum particle on the Poincar\\'e half-plane, a surface of constant negative Gaussian curvature. We show the bound state energy spectra for particles under specific poten...
Angle measures, general rotations, and roulettes in normed planes
Balestro, Vitor; Horváth, Ákos G.; Martini, Horst
2017-12-01
In this paper a special group of bijective maps of a normed plane (or, more generally, even of a plane with a suitable Jordan curve as unit circle) is introduced which we call the group of general rotations of that plane. It contains the isometry group as a subgroup. The concept of general rotations leads to the notion of flexible motions of the plane, and to the concept of Minkowskian roulettes. As a nice consequence of this new approach to motions the validity of strong analogues to the Euler-Savary equations for Minkowskian roulettes is proved.
Estimates of plastic loads for pipe bends under combined in-plane and out-of-plane bending moment
International Nuclear Information System (INIS)
Kim, Nak Hyun; Oh, Chang Sik; Kim, Yun Jae
2008-01-01
This paper provides a method to estimate plastic loads (defined by twice-elastic-slope) for pipe bends under combined in-plane and out-of-plane bending moment, based on detailed 3-D FE limit analyses using elastic-perfectly plastic materials. Because closing bending moment is always lower than opening bending moment, the combination of in-plane closing bending and out-of-plane bending moment becomes the most significant case. Due to conservatism of each bending moments, the resultant moment provided by ASME B and PV code is unduly conservative. However, the concept of the resultant moment is still valid. In this paper, FE results show that the accurate solutions of bending moments provide better estimates of plastic loads of pipe bend under combined in-plane bending and out-of-plane bending moment
In-plane and out-of-plane emission of nuclear matter in Au+Au collisions
International Nuclear Information System (INIS)
Bastid, N.; Dupieux, P.; Ramillien, V.; Alard, J.P.; Amouroux, V.; Berger, L.; Boussange, S.; Fraysse, L.; Ibnouzahir, M.; Montarou, G.
1995-01-01
Collective flow effects in Au (E/A = 150 to 800 MeV) on Au collisions measured with the phase I setup of the FOPI detector at GSI - Darmstadt are presented. Directed side ward flow is studied, by the mean transverse momentum in the reaction plane x (y)>, without reaction plane reconstruction. A more quantitative measurement of the global amount of directed side ward flow is also made and some comparisons with the predictions of different QMD versions are given. Experimental results concerning the preferential emission of particles in a direction perpendicular to the reaction plane are also presented. Azimuthal distributions of fragments around the beam axis, with respect to the reaction plane are studied in the mid-rapidity region and the associated R N (out-of-plane/in-plane ratios) are extracted. The dependence of R N upon transverse momentum, centrality, fragment charge and bombarding energy is studied. (authors). 24 refs., 10 figs., 1 tab
Ultrasound-Guided Out-of-Plane vs. In-Plane Interscalene Catheters: A Randomized, Prospective Study
Schwenk, Eric S.; Gandhi, Kishor; Baratta, Jaime L.; Torjman, Marc; Epstein, Richard H.; Chung, Jaeyoon; Vaghari, Benjamin A.; Beausang, David; Bojaxhi, Elird; Grady, Bernadette
2015-01-01
Background: Continuous interscalene blocks provide excellent analgesia after shoulder surgery. Although the safety of the ultrasound-guided in-plane approach has been touted, technical and patient factors can limit this approach. We developed a caudad-to-cephalad out-of-plane approach and hypothesized that it would decrease pain ratings due to better catheter alignment with the brachial plexus compared to the in-plane technique in a randomized, controlled study. Objectives: To compare an out-...
ARBITRARY INTERACTION OF PLANE SUPERSONIC FLOWS
Directory of Open Access Journals (Sweden)
P. V. Bulat
2015-11-01
Full Text Available Subject of study.We consider the Riemann problem for parameters at collision of two plane flows at a certain angle. The problem is solved in the exact statement. Most cases of interference, both stationary and non-stationary gas-dynamic discontinuities, followed by supersonic flows can be reduced to the problem of random interaction of two supersonic flows. Depending on the ratio of the parameters in the flows, outgoing discontinuities turn out to be shock waves, or rarefactionwaves. In some cases, there is no solution at all. It is important to know how to find the domain of existence for the relevant decisions, as the type of shock-wave structures in these domains is known in advance. The Riemann problem is used in numerical methods such as the method of Godunov. As a rule, approximate solution is used, known as the Osher solution, but for a number of problems with a high precision required, solution of this problem needs to be in the exact statement. Main results.Domains of existence for solutions with different types of shock-wave structure have been considered. Boundaries of existence for solutions with two outgoing shock waves are analytically defined, as well as with the outgoing shock wave and rarefaction wave. We identify the area of Mach numbers and angles at which the flows interact and there is no solution. Specific flows with two outgoing rarefaction waves are not considered. Practical significance. The results supplement interference theory of stationary gas-dynamic discontinuities and can be used to develop new methods of numerical calculation with extraction of discontinuities.
Ishikawa, Kazuo; Nakao, Shota; Murakami, Gen; Rodríguez-Vázquez, Jose Francisco; Matsuoka, Tetsuya; Nakamuro, Makoto; Shimazu, Takeshi
2014-12-01
Recently, the radiological concept of retroperitoneal interfascial planes has been widely accepted to explain the extension of retroperitoneal pathologies. This study aimed to explore embryologically based corroborative evidence, which remains to be elucidated, for this concept. Using serial or semi-serial transverse sections from 29 human fetuses at the 5th-25th week of fetal age, we microscopically observed the development of the retroperitoneal fasciae and other structures in the retroperitoneal connective tissue. A hypothesis for the formation of the interfascial planes was generated from the developmental study and analysis of retroperitoneal fasciae in computed tomography images from 224 patients. Whereas the loose connective tissue was uniformly distributed in the retroperitoneum by the 9th week, the primitive renal and transversalis fasciae appeared at the 10th-12th week, as previous research has noted. By the 23rd week, the renal fascia, transversalis fascia, and primitive adipose tissue of the flank pad emerged. In addition, the primitive lateroconal fascia, which runs parallel to and close to the posterior renal fascia, emerged between the renal fascia and the adipose tissue of the flank pad. Conversely, pre-existing loose connective tissue was sandwiched between the opposing fasciae and was compressed and narrowed by the developing organs and fatty tissues. Through this developmental study, we provided the hypothesis that the compressed loose connective tissue and both opposed fasciae compose the interfascial planes. Analysis of the thickened retroperitoneal fasciae in computed tomography images supported this hypothesis. Further developmental or histological studies are required to verify our hypothesis.
Models of Quantum Space Time: Quantum Field Planes
Mack, G.; Schomerus, V.
1994-01-01
Quantum field planes furnish a noncommutative differential algebra $\\Omega$ which substitutes for the commutative algebra of functions and forms on a contractible manifold. The data required in their construction come from a quantum field theory. The basic idea is to replace the ground field ${\\bf C}$ of quantum planes by the noncommutative algebra ${\\cal A}$ of observables of the quantum field theory.
Random skew plane partitions with a piecewise periodic back wall
DEFF Research Database (Denmark)
Boutillier, Cedric; Mkrtchyan, Sevak; Reshetikhin, Nicolai
Random skew plane partitions of large size distributed according to an appropriately scaled Schur process develop limit shapes. In the present work we consider the limit of large random skew plane partitions where the inner boundary approaches a piecewise linear curve with non-lattice slopes. Muc...
Positivity properties of phase-plane distribution functions
Janssen, A.J.E.M.
1984-01-01
The aim of this paper is to compare the members of Cohen's class of phase-plane distributions with respect to positivity properties. It is known that certain averages (which are in a sense compatible with Heisenberg's uncertainty principle) of the Wigner distribution over the phase-plane yield
Bilinear phase-plane distribution functions and positivity
Janssen, A.J.E.M.
1985-01-01
There is a theorem of Wigner that states that phase-plane distribution functions involving the state bilinearly and having correct marginals must take negative values for certain states. The purpose of this paper is to support the statement that these phase-plane distribution functions are for
16 CFR Figure 1 to Part 1203 - Anatomical Planes
2010-01-01
... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Anatomical Planes 1 Figure 1 to Part 1203 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS SAFETY STANDARD FOR BICYCLE HELMETS Pt. 1203, Fig. 1 Figure 1 to Part 1203—Anatomical Planes ER10MR98.001 ...
Wood working: planing and moulding in the last frontier
David Nicholls
2007-01-01
Planing and moulding is an important step in the value-added manufacture of wood products, and recent advances in Alaska have been noteworthy. Just a few years ago, most planing occurred on simple shop planers, producing lumber for retail sale or for wood working uses such as cabinet stock. Currently there are at least 26 planers and 13 moulders in-production at...
Plane-wave least-squares reverse-time migration
Dai, Wei
2013-06-03
A plane-wave least-squares reverse-time migration (LSRTM) is formulated with a new parameterization, where the migration image of each shot gather is updated separately and an ensemble of prestack images is produced along with common image gathers. The merits of plane-wave prestack LSRTM are the following: (1) plane-wave prestack LSRTM can sometimes offer stable convergence even when the migration velocity has bulk errors of up to 5%; (2) to significantly reduce computation cost, linear phase-shift encoding is applied to hundreds of shot gathers to produce dozens of plane waves. Unlike phase-shift encoding with random time shifts applied to each shot gather, plane-wave encoding can be effectively applied to data with a marine streamer geometry. (3) Plane-wave prestack LSRTM can provide higher-quality images than standard reverse-time migration. Numerical tests on the Marmousi2 model and a marine field data set are performed to illustrate the benefits of plane-wave LSRTM. Empirical results show that LSRTM in the plane-wave domain, compared to standard reversetime migration, produces images efficiently with fewer artifacts and better spatial resolution. Moreover, the prestack image ensemble accommodates more unknowns to makes it more robust than conventional least-squares migration in the presence of migration velocity errors. © 2013 Society of Exploration Geophysicists.
Lower bound plane stress element for modelling 3D structures
DEFF Research Database (Denmark)
Herfelt, Morten Andersen; Poulsen, Peter Noe; Hoang, Linh Cao
2017-01-01
In-plane action is often the primary load-carrying mechanism of reinforced concrete structures. The plate bending action will be secondary, and the behaviour of the structure can be modelled with a reasonable accuracy using a generalised three-dimensional plane stress element. In this paper...
Crack Propagation in Plane Strain under Variable Amplitude Loading
DEFF Research Database (Denmark)
Ricardo, Luiz Carlos Hernandes
2010-01-01
. In this paper procedures to determine the crack opening and closure by finite elements analyses in plane strain will be presented. The objective of this paper is also provide a review of retardation models under variable spectrum loading considering plane strain constraint as well as their correlation...
Selection of planes in nuclear magnetic resonance tomography
International Nuclear Information System (INIS)
Bonagamba, T.J.
1986-01-01
A prototype aiming to obtain images in nuclear magnetic resonance tomography was developed, by adjusting NMR spectrometer in the IFQSC Laboratory. The techniques for selecting planes were analysed by a set of computer codes, which were elaborated from Bloch equation solutions to simulate the spin system behaviour. Images were obtained using planes with thickness inferior to 1 cm. (M.C.K.)
Plane Stratified Flow in a Room Ventilated by Displacement Ventilation
DEFF Research Database (Denmark)
Nielsen, Peter Vilhelm; Nickel, J.; Baron, D. J. G.
2004-01-01
The air movement in the occupied zone of a room ventilated by displacement ventilation exists as a stratified flow along the floor. This flow can be radial or plane according to the number of wall-mounted diffusers and the room geometry. The paper addresses the situations where plane flow...
Plane-wave least-squares reverse-time migration
Dai, Wei; Schuster, Gerard T.
2013-01-01
. The merits of plane-wave prestack LSRTM are the following: (1) plane-wave prestack LSRTM can sometimes offer stable convergence even when the migration velocity has bulk errors of up to 5%; (2) to significantly reduce computation cost, linear phase
Surface anatomy and anatomical planes in the adult turkish population.
Uzun, C; Atman, E D; Ustuner, E; Mirjalili, S A; Oztuna, D; Esmer, T S
2016-03-01
Surface anatomy and anatomical planes are widely used in education and clinical practice. The planes are largely derived from cadaveric studies and their projections on the skin show discrepancies between and within anatomical reference textbooks. In this study, we reassessed the accuracy of common thoracic and abdominopelvic anatomical planes using computed tomography (CT) imaging in the live adult Turkish population. After patients with distorting pathologies had been excluded, CT images of 150 supine patients at the end tidal inspiration were analyzed. Sternal angle, transpyloric, subcostal, supracristal and pubic crest planes and their relationships to anatomical structures were established by dual consensus. The tracheal bifurcation, azygos vein/superior vena cava (SVC) junction and pulmonary bifurcation were usually below the sternal angle while the concavity of the aortic arch was generally within the plane. The tip of the tenth rib, the superior mesenteric artery and the portal vein were usually within the transpyloric plane while the renal hila and the fundus of the gallbladder were below it. The inferior mesenteric artery was below the subcostal plane and the aortic bifurcation was below the supracristal plane in most adults. Projectional surface anatomy is fundamental to medical education and clinical practice. Modern cross-sectional imaging techniques allow large groups of live patients to be examined. Classic textbook information regarding anatomy needs to be reviewed and updated using the data gathered from these recent studies, taking ethnic differences into consideration. © 2015 Wiley Periodicals, Inc.
Plane Transformations in a Complex Setting III: Similarities
Dana-Picard, Thierry
2009-01-01
This is the third part of a study of plane transformations described in a complex setting. After the study of homotheties, translations, rotations and reflections, we proceed now to the study of plane similarities, either direct or inverse. Their group theoretical properties are described, and their action on classical geometrical objects is…
Precession of a Spinning Ball Rolling down an Inclined Plane
Cross, Rod
2015-01-01
A routine problem in an introductory physics course considers a rectangular block at rest on a plane inclined at angle a to the horizontal. In order for the block not to slide down the incline, the coefficient of sliding friction, µ, must be at least tan a. The situation is similar for the case of a ball rolling down an inclined plane. In order…
Identification of Critical Transmission Limits in Injection Impedance Plane
DEFF Research Database (Denmark)
Jóhannsson, Hjörtur; Østergaard, Jacob; Nielsen, Arne Hejde
2012-01-01
In this paper, equations are derived that describe the mapping of critical boundaries and characteristic lines from the three dimensionalPQV-surface into the two-dimensional injection impedance plane (load impedance plane for both positive and negativeresistance). The expressions derived....... The situational awareness method will bedescribed in a later paper, where this paper focuses on the derivations of some system characteristics in the injection (or load)impedance plane. The critical lines from the PQV-surface that are mapped into the impedance plane are the ones representing theconditions where...... the partial derivatives of the variables P,Q and V in respect to each other become zero. In addition to the mappingof the critical lines, some characteristic lines are mapped as well. These include the mapping of the lines of constant P,Q,Vand d from the PQV-surface into the impedance plane. All of the mapped...
Phase Plane Analysis Method of Nonlinear Traffic Phenomena
Directory of Open Access Journals (Sweden)
Wenhuan Ai
2015-01-01
Full Text Available A new phase plane analysis method for analyzing the complex nonlinear traffic phenomena is presented in this paper. This method makes use of variable substitution to transform a traditional traffic flow model into a new model which is suitable for the analysis in phase plane. According to the new model, various traffic phenomena, such as the well-known shock waves, rarefaction waves, and stop-and-go waves, are analyzed in the phase plane. From the phase plane diagrams, we can see the relationship between traffic jams and system instability. So the problem of traffic flow could be converted into that of system stability. The results show that the traffic phenomena described by the new method is consistent with that described by traditional methods. Moreover, the phase plane analysis highlights the unstable traffic phenomena we are chiefly concerned about and describes the variation of density or velocity with time or sections more clearly.
Effect of twinning plane on superconductor magnetic properties
International Nuclear Information System (INIS)
Buzdin, A.I.; Kuptsov, D.A.
1989-01-01
Effect of twinning planes on pinning of the Abrikosov vortices in superconductors of the second order with the Ginsburg-Landau parameter, κ >> 1, is considered. The modified Ginsburg-Landau functional, where the effect of superconducting properties improvement near the twinning plane is taken into account by adding the additional δ-function component, is used to descibe superconductivity of twinning plane. Force of interaction of a vortex filament and the twinning plane is calculated. It is shown that in case of the twinning plane opaque to electrons, additional attractive force, being analogous to that occurring in the problem on the surface Been-Livingston barrier, affects the vortex filament. The results can explain anisotropy of vortex pinning observed in the periodic twinning structure in high-temperature superconductors
Peptidoglycan architecture can specify division planes in Staphylococcus aureus.
Turner, Robert D; Ratcliffe, Emma C; Wheeler, Richard; Golestanian, Ramin; Hobbs, Jamie K; Foster, Simon J
2010-06-15
Division in Staphylococci occurs equatorially and on specific sequentially orthogonal planes in three dimensions, resulting, after incomplete cell separation, in the 'bunch of grapes' cluster organization that defines the genus. The shape of Staphylococci is principally maintained by peptidoglycan. In this study, we use Atomic Force Microscopy (AFM) and fluorescence microscopy with vancomycin labelling to examine purified peptidoglycan architecture and its dynamics in Staphylococcus aureus and correlate these with the cell cycle. At the presumptive septum, cells were found to form a large belt of peptidoglycan in the division plane before the centripetal formation of the septal disc; this often had a 'piecrust' texture. After division, the structures remain as orthogonal ribs, encoding the location of past division planes in the cell wall. We propose that this epigenetic information is used to enable S. aureus to divide in sequentially orthogonal planes, explaining how a spherical organism can maintain division plane localization with fidelity over many generations.
Directory of Open Access Journals (Sweden)
N. H. Abd Rahman
2014-01-01
Full Text Available Reflector antennas have been widely used in many areas. In the implementation of parabolic reflector antenna for broadcasting satellite applications, it is essential for the spacecraft antenna to provide precise contoured beam to effectively serve the required region. For this purpose, combinations of more than one beam are required. Therefore, a tool utilizing ray tracing method is developed to calculate precise off-axis beams for multibeam antenna system. In the multibeam system, each beam will be fed from different feed positions to allow the main beam to be radiated at the exact direction on the coverage area. Thus, detailed study on caustics of a parabolic reflector antenna is performed and presented in this paper, which is to investigate the behaviour of the rays and its relation to various antenna parameters. In order to produce accurate data for the analysis, the caustic behaviours are investigated in two distinctive modes: scanning plane and transverse plane. This paper presents the detailed discussions on the derivation of the ray tracing algorithms, the establishment of the equations of caustic loci, and the verification of the method through calculation of radiation pattern.
Modelling out-of-plane and in-plane resonant modes of microplates in liquid media
International Nuclear Information System (INIS)
Ruiz-Díez, V; Hernando-García, J; Manzaneque, T; Sánchez-Rojas, J L; Kucera, M; Schmid, U
2015-01-01
In this article, the quality factor and the resonant frequency of different vibrating modes of microplates immersed in liquid are simulated by means of a finite element method (FEM) and compared with experimental data. For the in-plane modes, we studied the first extensional mode of mid-point supported microplates, which may be efficiently actuated by a thin piezoelectric film on top of the structure. A comparison of different approaches to account for the viscous loading in computationally efficient 2D finite element models is presented. As an alternative to the harmonic response, a novel multitone excitation in the fluid–structure interaction model allows for the calculation of the frequency response of the structure. For the out-of-plane modes, different modes were simulated and compared to analytical models to validate our approach. Our 2D FEM model yields more accurate estimations of the experimental resonance frequency and quality factors than the available analytical models. With the help of these tools, the applicability of the micro-resonators as viscosity and density sensors is discussed. (paper)
Djakou, Audrey Kamta; Darmon, Michel; Fradkin, Larissa; Potel, Catherine
2015-11-01
Diffraction phenomena studied in electromagnetism, acoustics, and elastodynamics are often modeled using integrals, such as the well-known Sommerfeld integral. The far field asymptotic evaluation of such integrals obtained using the method of steepest descent leads to the classical Geometrical Theory of Diffraction (GTD). It is well known that the method of steepest descent is inapplicable when the integrand's stationary phase point coalesces with its pole, explaining why GTD fails in zones where edge diffracted waves interfere with incident or reflected waves. To overcome this drawback, the Uniform geometrical Theory of Diffraction (UTD) has been developed previously in electromagnetism, based on a ray theory, which is particularly easy to implement. In this paper, UTD is developed for the canonical elastodynamic problem of the scattering of a plane wave by a half-plane. UTD is then compared to another uniform extension of GTD, the Uniform Asymptotic Theory (UAT) of diffraction, based on a more cumbersome ray theory. A good agreement between the two methods is obtained in the far field.
Ibrahim, Hazem
2016-09-19
The unrelenting increase in the population of mobile users and their traffic demands drive cellular network operators to densify their network infrastructure. Network densification shrinks the footprint of base stations (BSs) and reduces the number of users associated with each BS, leading to an improved spatial frequency reuse and spectral efficiency, and thus, higher network capacity. However, the densification gain comes at the expense of higher handover rates and network control overhead. Hence, user’s mobility can diminish or even nullifies the foreseen densification gain. In this context, splitting the control plane ( C -plane) and user plane ( U -plane) is proposed as a potential solution to harvest densification gain with reduced cost in terms of handover rate and network control overhead. In this paper, we use stochastic geometry to develop a tractable mobility-aware model for a two-tier downlink cellular network with ultra-dense small cells and C -plane/ U -plane split architecture. The developed model is then used to quantify the effect of mobility on the foreseen densification gain with and without C -plane/ U -plane split. To this end, we shed light on the handover problem in dense cellular environments, show scenarios where the network fails to support certain mobility profiles, and obtain network design insights.
Ultrasound-Guided Out-of-Plane vs. In-Plane Interscalene Catheters: A Randomized, Prospective Study.
Schwenk, Eric S; Gandhi, Kishor; Baratta, Jaime L; Torjman, Marc; Epstein, Richard H; Chung, Jaeyoon; Vaghari, Benjamin A; Beausang, David; Bojaxhi, Elird; Grady, Bernadette
2015-12-01
Continuous interscalene blocks provide excellent analgesia after shoulder surgery. Although the safety of the ultrasound-guided in-plane approach has been touted, technical and patient factors can limit this approach. We developed a caudad-to-cephalad out-of-plane approach and hypothesized that it would decrease pain ratings due to better catheter alignment with the brachial plexus compared to the in-plane technique in a randomized, controlled study. To compare an out-of-plane interscalene catheter technique to the in-plane technique in a randomized clinical trial. Eighty-four patients undergoing open shoulder surgery were randomized to either the in-plane or out-of-plane ultrasound-guided continuous interscalene technique. The primary outcome was VAS pain rating at 24 hours. Secondary outcomes included pain ratings in the recovery room and at 48 hours, morphine consumption, the incidence of catheter dislodgments, procedure time, and block difficulty. Procedural data and all pain ratings were collected by blinded observers. There were no differences in the primary outcome of median VAS pain rating at 24 hours between the out-of-plane and in-plane groups (1.50; IQR, [0 - 4.38] vs. 1.25; IQR, [0 - 3.75]; P = 0.57). There were also no differences, respectively, between out-of-plane and in-plane median PACU pain ratings (1.0; IQR, [0 - 3.5] vs. 0.25; IQR, [0 - 2.5]; P = 0.08) and median 48-hour pain ratings (1.25; IQR, [1.25 - 2.63] vs. 0.50; IQR, [0 - 1.88]; P = 0.30). There were no differences in any other secondary endpoint. Our out-of-plane technique did not provide superior analgesia to the in-plane technique. It did not increase the number of complications. Our technique is an acceptable alternative in situations where the in-plane technique is difficult to perform.
Carson, John C.
1989-09-01
The papers contained in this volume focus on the implementation and application of Z-plane focal array technology. Topics discussed include civil and military applications of Z-plane technology, electronic design and technology for on-scale plane signal processing, detector development and fabrication technology, and Z-plane module development and producibility. Papers are presented on future capabilities of Z-plane technology, comparison of planar and Z-plane focal plane technologies for dim target detection, Z-plane modules as target extraction engines, and high complexity tape automated bonding application for space hardware.
Vectorial and plane energy fluences - useful concepts in radiation physics
International Nuclear Information System (INIS)
Carlsson, C.A.
1977-06-01
The vectorial physical quantities describing the radiation field are defined in this report. The use of these quantities is rare in the radiation dosimetry literature since a knowledge of the directions of motion of the ionizing particle is often uninteresting when determining absorbed doses. However the plane energy fluence rate is a useful quantity in cases with plane irradiation geometries. The plane energy fluence rate is closely related to the vectorial energy fluence rate. The backscattering properties of a medium can be expressed in terms either of its albedo or its reflection-coefficient (backscatter-coefficient). These quantities are discussed in order to derive useful relations between the plane energy fluence and the energy fluence at points on an extended plane surface. Examples are also given of erroneous use of energy fluence instead of vectorial or plane energy fluence. The examples are taken from roentgen diagnostic examinations. To prevent further mistakes it could be valuable if the quantities of vectorial and plane fluences were introduced in text books in radiation dosimetry. Awaiting for this, this report may hopefully be useful. (E.R.)
Miniaturized Fourier-plane fiber scanner for OCT endoscopy
International Nuclear Information System (INIS)
Vilches, Sergio; Kretschmer, Simon; Ataman, Çağlar; Zappe, Hans
2017-01-01
A forward-looking endoscopic optical coherence tomography (OCT) probe featuring a Fourier-plane fiber scanner is designed, manufactured and characterized. In contrast to common image-plane fiber scanners, the Fourier-plane scanner is a telecentric arrangement that eliminates vignetting and spatial resolution variations across the image plane. To scan the OCT beam in a spiral pattern, a tubular piezoelectric actuator is used to resonate an optical fiber bearing a collimating GRIN lens at its tip. The free-end of the GRIN lens sits at the back focal plane of an objective lens, such that its rotation replicates the beam angles in the collimated region of a classical telecentric 4f optical system. Such an optical arrangement inherently has a low numerical aperture combined with a relatively large field-of-view, rendering it particularly useful for endoscopic OCT imaging. Furthermore, the optical train of the Fourier-plane scanner is shorter than that of a comparable image-plane scanner by one focal length of the objective lens, significantly shortening the final arrangement. As a result, enclosed within a 3D printed housing of 2.5 mm outer diameter and 15 mm total length, the developed probe is the most compact forward-looking endoscopic OCT imager to date. Due to its compact form factor and compatibility with real-time OCT imaging, the developed probe is also ideal for use in the working channel of flexible endoscopes as a potential optical biopsy tool. (paper)
Miniaturized Fourier-plane fiber scanner for OCT endoscopy
Vilches, Sergio; Kretschmer, Simon; Ataman, Çağlar; Zappe, Hans
2017-10-01
A forward-looking endoscopic optical coherence tomography (OCT) probe featuring a Fourier-plane fiber scanner is designed, manufactured and characterized. In contrast to common image-plane fiber scanners, the Fourier-plane scanner is a telecentric arrangement that eliminates vignetting and spatial resolution variations across the image plane. To scan the OCT beam in a spiral pattern, a tubular piezoelectric actuator is used to resonate an optical fiber bearing a collimating GRIN lens at its tip. The free-end of the GRIN lens sits at the back focal plane of an objective lens, such that its rotation replicates the beam angles in the collimated region of a classical telecentric 4f optical system. Such an optical arrangement inherently has a low numerical aperture combined with a relatively large field-of-view, rendering it particularly useful for endoscopic OCT imaging. Furthermore, the optical train of the Fourier-plane scanner is shorter than that of a comparable image-plane scanner by one focal length of the objective lens, significantly shortening the final arrangement. As a result, enclosed within a 3D printed housing of 2.5 mm outer diameter and 15 mm total length, the developed probe is the most compact forward-looking endoscopic OCT imager to date. Due to its compact form factor and compatibility with real-time OCT imaging, the developed probe is also ideal for use in the working channel of flexible endoscopes as a potential optical biopsy tool.
Transparency in stereopsis: parallel encoding of overlapping depth planes.
Reeves, Adam; Lynch, David
2017-08-01
We report that after extensive training, expert adults can accurately report the number, up to six, of transparent overlapping depth planes portrayed by brief (400 ms or 200 ms) random-element stereoscopic displays, and can well discriminate six from seven planes. Naïve subjects did poorly above three planes. Displays contained seven rows of 12 randomly located ×'s or +'s; jittering the disparities and number in each row to remove spurious cues had little effect on accuracy. Removing the central 3° of the 10° display to eliminate foveal vision hardly reduced the number of reportable planes. Experts could report how many of six planes contained +'s when the remainder contained ×'s, and most learned to report up to six planes in reverse contrast (left eye white +'s; right eye black +'s). Long-term training allowed some experts to reach eight depth planes. Results suggest that adult stereoscopic vision can learn to distinguish the outputs of six or more statistically independent, contrast-insensitive, narrowly tuned, asymmetric disparity channels in parallel.
Two-plane symmetry in the structural organization of man.
Ermolenko, A E
2005-01-01
Manifestations of symmetry in the human structural organization in ontogenesis and phylogenetic development are analysed. A concept of macrobiocrystalloid with inherent complex symmetry is proposed for the description of the human organism in its integrity. The symmetry can be characterized as two-plane radial (quadrilateral), where the planar symmetry is predominant while the layout of organs of radial symmetry is subordinated to it. Out of the two planes of symmetry (sagittal and horizontal), the sagittal plane is predominant: (a) the location of the organs is governed by two principles: in compliance with the symmetry planes and in compliance with the radial symmetry around cavities; (b) the location of the radial symmetry organs is also governed by the principle of two-plane symmetry; (c) out of the four antimeres of two-plane symmetry, two are paired while the other two have merged into one organ; (d) some organs which are antimeres relative to the horizontal plane are located at the cranial end of the organism (sensory organs, cerebrum-cerebellum, heart-spleen and others). The two-plane symmetry is formed by two mechanisms--(a) the impact of morphogenetic fields of the whole crystalloid organism during embriogenesis and (b) genetic mechanisms of the development of chromosomes having two-plane symmetry. When comparing mineral and biological entities we should consider not the whole immobile crystal but only the active superficial part of a growing or dissolving crystal, the interface between the crystal surface and the crystal-forming environment which directly controls crystal growth and adapts itself to it, as well as crystal feed stock expressed in the structure of concentration flows. The symmetry of the chromosome, of the embrion at the early stages of cell cleavage as well as of some organs and systems in their phylogenetic development is described.
A Study of the Gamma-Ray Burst Fundamental Plane
International Nuclear Information System (INIS)
Dainotti, M. G.; Hernandez, X.; Postnikov, S.; Nagataki, S.; O’brien, P.; Willingale, R.; Striegel, S.
2017-01-01
Long gamma-ray bursts (GRBs) with a plateau phase in their X-ray afterglows obey a 3D relation, between the rest-frame time at the end of the plateau, T a , its corresponding X-ray luminosity, L a , and the peak luminosity in the prompt emission, L peak . This 3D relation identifies a GRB fundamental plane whose existence we here confirm. Here we include the most recent GRBs observed by Swift to define a “gold sample” (45 GRBs) and obtain an intrinsic scatter about the plane compatible within 1 σ with the previous result. We compare GRB categories, such as short GRBs with extended emission (SEE), X-ray flashes, GRBs associated with supernovae, a sample of only long-duration GRBs (132), selected from the total sample by excluding GRBs of the previous categories, and the gold sample, composed by GRBs with light curves with good data coverage and relatively flat plateaus. We find that the relation planes for each of these categories are not statistically different from the gold fundamental plane, with the exception of the SSE, which are hence identified as a physically distinct class. The gold fundamental plane has an intrinsic scatter smaller than any plane derived from the other sample categories. Thus, the distance of any particular GRB category from this plane becomes a key parameter. We computed the several category planes with T a as a dependent parameter obtaining for each category smaller intrinsic scatters (reaching a reduction of 24% for the long GRBs). The fundamental plane is independent from several prompt and afterglow parameters.
A Study of the Gamma-Ray Burst Fundamental Plane
Energy Technology Data Exchange (ETDEWEB)
Dainotti, M. G. [Department of Physics and Astronomy, Stanford University, Via Pueblo Mall 382, Stanford, CA 94305-4060 (United States); Hernandez, X. [Instituto de Astronomía, Universidad Nacional Autónoma de México, Ciudad de México 04510, México (Mexico); Postnikov, S. [The Center for Exploration of Energy and Matter, Indiana University, Bloomington, IN 47405 (United States); Nagataki, S. [RIKEN, Hirosawa, Wako Saitama (Japan); O’brien, P.; Willingale, R. [Department of Physics and Astronomy, University of Leicester, Road Leicester LE1 7RH (United Kingdom); Striegel, S., E-mail: mdainott@stanford.edu, E-mail: dainotti@oa.uj.edu.pl, E-mail: mariagiovannadainotti@yahoo.it, E-mail: xavier@astro.unam.mx, E-mail: postsergey@gmail.com, E-mail: shigehiro.nagataki@riken.jp, E-mail: zrw@le.ac.uk, E-mail: stephanie.striegel@sjsu.edu [Department of Physics and Astronomy, San Jose State University, One Washington Square, San Jose, CA 95192 (United States)
2017-10-20
Long gamma-ray bursts (GRBs) with a plateau phase in their X-ray afterglows obey a 3D relation, between the rest-frame time at the end of the plateau, T {sub a} , its corresponding X-ray luminosity, L {sub a} , and the peak luminosity in the prompt emission, L {sub peak}. This 3D relation identifies a GRB fundamental plane whose existence we here confirm. Here we include the most recent GRBs observed by Swift to define a “gold sample” (45 GRBs) and obtain an intrinsic scatter about the plane compatible within 1 σ with the previous result. We compare GRB categories, such as short GRBs with extended emission (SEE), X-ray flashes, GRBs associated with supernovae, a sample of only long-duration GRBs (132), selected from the total sample by excluding GRBs of the previous categories, and the gold sample, composed by GRBs with light curves with good data coverage and relatively flat plateaus. We find that the relation planes for each of these categories are not statistically different from the gold fundamental plane, with the exception of the SSE, which are hence identified as a physically distinct class. The gold fundamental plane has an intrinsic scatter smaller than any plane derived from the other sample categories. Thus, the distance of any particular GRB category from this plane becomes a key parameter. We computed the several category planes with T {sub a} as a dependent parameter obtaining for each category smaller intrinsic scatters (reaching a reduction of 24% for the long GRBs). The fundamental plane is independent from several prompt and afterglow parameters.
Anatomical planes: are we teaching accurate surface anatomy?
Mirjalili, S Ali; McFadden, Sarah L; Buckenham, Tim; Wilson, Ben; Stringer, Mark D
2012-10-01
Anatomical planes used in clinical practice and teaching anatomy are largely derived from cadaver studies. Numerous inconsistencies in clinically important surface markings exist between and within anatomical reference texts. The aim of this study was to reassess the accuracy of common anatomical planes in vivo using computed tomographic (CT) imaging. CT scans of the trunk in supine adults at end tidal inspiration were analyzed by dual consensus reporting to determine the anatomy of five anatomical planes: sternal angle, transpyloric, subcostal, supracristal, and the plane of the pubic crest. Patients with kyphosis, scoliosis, or abnormal lordosis, distorting space-occupying lesions, or visceromegaly were excluded. Among 153 thoracic CT scans (mean age 63 years, 53% female), the sternal angle was most common at T4 (females) or T4/5 (males) vertebral level, and the tracheal bifurcation, aortic arch, and pulmonary trunk were most often below this plane. In 108 abdominal CT scans (mean age 60 years, 59% female), the subcostal and supracristal planes were most often at L2 (58%) and L4 (69%), respectively. In 52 thoracoabdominal CT scans (mean age 61 years, 56% female), the transpyloric plane was between lower L1 and upper L2 (75%); in this plane were the superior mesenteric artery (56%), formation of the portal vein (53%), tip of the ninth rib (60%), and the left renal hilum (54%), but the right renal hilum and gallbladder fundus were more often below. The surface anatomy of anatomical planes needs revising in the light of results from living subjects using modern imaging techniques. Copyright © 2012 Wiley Periodicals, Inc.
An Image Encryption Method Based on Bit Plane Hiding Technology
Institute of Scientific and Technical Information of China (English)
LIU Bin; LI Zhitang; TU Hao
2006-01-01
A novel image hiding method based on the correlation analysis of bit plane is described in this paper. Firstly, based on the correlation analysis, different bit plane of a secret image is hided in different bit plane of several different open images. And then a new hiding image is acquired by a nesting "Exclusive-OR" operation on those images obtained from the first step. At last, by employing image fusion technique, the final hiding result is achieved. The experimental result shows that the method proposed in this paper is effective.
New family of exact solutions for colliding plane gravitational waves
International Nuclear Information System (INIS)
Yurtsever, U.
1988-01-01
We construct an infinite-parameter family of exact solutions to the vacuum Einstein field equations describing colliding gravitational plane waves with parallel polarizations. The interaction regions of the solutions in this family are locally isometric to the interiors of those static axisymmetric (Weyl) black-hole solutions which admit both a nonsingular horizon, and an analytic extension of the exterior metric to the interior of the horizon. As a member of this family of solutions we also obtain, for the first time, a colliding plane-wave solution where both of the two incoming plane waves are purely anastigmatic, i.e., where both incoming waves have equal focal lengths
Efficient Return Algorithms For Associated Plasticity With Multiple Yield Planes
DEFF Research Database (Denmark)
Clausen, Johan Christian; Damkilde, Lars; Andersen, Lars
2006-01-01
of such criteria. The return formulae are in closed form and no iteration is required. The method accounts for three types of stress return: Return to a single yield plane, to a discontinuity line at the intersection of two yield planes and to a discontinuity point at the intersection between three or more yield...... planes. The infinitesimal and the consistent elastoplastic constitutive matrix are calculated for each type of stress return, as are the conditions to ascertain which type of return is required. The method is exemplified with the Mohr-Coulomb yield criterion....
Acceleration of planes segmentation using normals from previous frame
Gritsenko, Pavel; Gritsenko, Igor; Seidakhmet, Askar; Abduraimov, Azizbek
2017-12-01
One of the major problem in integration process of robots is to make them able to function in a human environment. In terms of computer vision, the major feature of human made rooms is the presence of planes [1, 2, 20, 21, 23]. In this article, we will present an algorithm dedicated to increase speed of a plane segmentation. The algorithm uses information about location of a plane and its normal vector to speed up the segmentation process in the next frame. In conjunction with it, we will address such aspects of ICP SLAM as performance and map representation.
Directory of Open Access Journals (Sweden)
Luciana G. Teixeira
Full Text Available ABSTRACT: This paper pretends to demonstrate the effect of the combination of transversus abdominis plane block (TAP block and Serratus plane block (SP block techniques in analgesia of 4 dogs undergoing total unilateral mastectomy. Dogs were premedicated with methadone (0.5mg.kg-1 intramuscularly. Anesthesia was induced with propofol (6mg.kg-1 and midazolam (0.3mg.kg-1 and maintained with isoflurane. SP and TAP block were performed unilaterally using ultrasound by the injection of bupivacaine 0.25% (0.3mL kg-1 diluted with NaCl solution 1:1. Heart rate (HR, respiratory rate (f, non-invasive arterial pressure, esophageal temperature (T, oxygen saturation (SpO2 and electrocardiogram were monitored continuously. Animals were monitored for two and four hours after extubation for pain by using the Canine Acute Pain Scale from Colorado State University. Two hours after extubation, tramadol (4mg.kg-1 and dipyrone (25mg.kg-1 was administered to all dogs. It was not observed any alteration on cardiac rhythm. HR, f, T and mean arterial pressure remained below the preincisional values for all dogs. No dog required intraoperative rescue analgesia. Recovery from anesthesia was without any complication. All animals scored 0 (0/5 at pain scale, two and four hours after extubation and none of them expressed concern over the surgical wound. Dogs were able to walk before two hours after extubation. The combination of both techniques is effective in anesthetic blocking the thoracic and abdominal walls and it is suggested both may be included in the multimodal analgesia protocols for this type of surgery.
Al Quran, Firas A M; Hazza'a, Abdalla; Al Nahass, Nabeel
2010-12-01
This study aimed at determining the most reliable ala-tragus line as a guide for the orientation of the occlusal plane in complete denture patients by use of cephalometric landmarks on dentate volunteers. Analysis was made for prosthodontically related craniofacial reference lines and angles of lateral cephalometric radiographs taken for 47 dentate adults. Variables were determined and data were analyzed using SPSS (SPSS, Inc., Chicago, IL). Occlusal plane angle formed between the occlusal plane and Camper's plane had the lowest mean value in the angle formed with Camper's I, which represents the measure taken from the superior border of the tragus of the ear with a score of 2.1°. The highest was measured in the angle formed with Camper's III with a score of 6.1°, while the angle formed with Camper's II was 3.2°. The differences between the three planes in relation to the occlusal plane was significant (p < 0.001). The superior border of the tragus with the inferior border of the ala of the nose was most accurate in orienting the occlusal plane. © 2010 by The American College of Prosthodontists.
Piraccini, E; Biondi, G; Byrne, H; Calli, M; Bellantonio, D; Musetti, G; Maitan, S
2018-05-16
Pectoral Nerves Block (PECS) and Serratus Plane Block (SPB) have been used to treat persistent post-surgical pain after breast and thoracic surgery; however, they cannot block the internal mammary region, so a residual pain may occur in that region. Parasternal block (PSB) and Thoracic Transversus Plane Block (TTP) anaesthetize the anterior branches of T2-6 intercostal nerves thus they can provide analgesia to the internal mammary region. We describe a 60-year-old man suffering from right post-thoracotomy pain syndrome with residual pain located in the internal mammary region after a successful treatment with PECS and SPB. We performed a PSB and TTP and hydrodissection of fascial planes with triamcinolone and Ropivacaine. Pain disappeared and the result was maintained 3 months later. This report suggests that PSB and TTP with local anaesthetic and corticosteroid with hydrodissection of fascial planes might be useful to treat a post thoracotomy pain syndrome located in the internal mammary region. The use of Transversus Thoracic Plane and Parasternal Blocks and fascial planes hydrodissection as a novel therapeutic approach to treat a residual post thoracotomy pain syndrome even when already treated with Pectoral Nerves Block and Serratus Plane Block. © 2018 European Pain Federation - EFIC®.
Shitano, Fuki; Kido, Aki; Kataoka, Masako; Fujimoto, Koji; Kiguchi, Kayo; Fushimi, Yasutaka; Togashi, Kaori
2016-01-01
Uterine peristalsis is supposed to be closely related to the early stages of reproduction. Sperms are preferentially transported from the uterine cervix to the side of the tube with the dominant follicle. However, with respect to magnetic resonance imaging (MRI), uterine peristalsis has only been evaluated at the sagittal plane of cine MRI. To evaluate and compare uterine peristalsis both on sagittal and coronal planes using cine MRI. Internal ethics committee approval was obtained, and subjects provided informed written consent. Thirty-one women underwent MRI scans in the periovulatory phase of the menstrual cycle. Cine MR images obtained by fast advanced spin echo sequence at 3-T field strength magnet (Toshiba Medical Systems) were visually evaluated by two independent radiologists. The frequency and the direction of peristalsis, and the presence of outer myometrium conduction of signal intensities (OMC), were evaluated. The laterality of the dominant follicle was determined on axial images and compared with the peristaltic direction in fundus. The subjects in which peristaltic directions were more clearly recognized were significantly frequent in coronal planes than in sagittal planes (P < 0.05). There was no significant difference in the peristaltic frequency between the sagittal and the coronal plane. However, the OMC was more recognized in the coronal plane than in the sagittal plane (P < 0.05). Peristaltic waves conducted toward the possible ovulation side were observed in only three of the 10 subjects. OMC of uterine peristalsis was better demonstrated in the coronal plane compared to the sagittal plane. © The Foundation Acta Radiologica 2015.
Lumbar pedicle screw placement: Using only AP plane imaging
Directory of Open Access Journals (Sweden)
Anil Sethi
2012-01-01
Conclusion: Placement of pedicle screws under fluoroscopic guidance using AP plane imaging alone with tactile guidance is safe, fast, and reliable. However, a good understanding of the radiographic landmarks is a prerequisite.
[A cephalometric study on determining the orientation of occlusal plane].
Xie, J; Zhao, Y; Chao, Y; Luo, W
1993-12-01
A study of the parallel relationship between the occlusal plane and the line connecting nasal alar and tragus was made in 90 dentulous cases by using cephalometry. The results show that the line connecting the inferior point of nasal alar and the mid-point of tragus runs much more parallel with the occlusal plane. The regression equation reveals a "line of closest fitting". It was used in the prosthetic treatment for 50 edentulous patients with good clinical results. The line connecting the inferior point of nasal alar and the mid-point of tragus therefore represents a proper reference plane for determining occlusal plane and hence should be still a valuable index in clinical dentistry.
Occlusal plane location in edentulous patients: a review.
Shetty, Sanath; Zargar, Nazia Majeed; Shenoy, Kamalakanth; Rekha, V
2013-09-01
Occlusal plane orientation is an important factor in the construction of a complete denture. Occlusal plane could be oriented using landmarks in the mandibular arch as well as in the maxillary arch. In the mandibular arch there are few landmarks which could be used to orient the occlusal plane like the retromolar pad, corner of the lips (lower lip length) whereas the maxillary arch has a number of landmarks, of which the ala-tragal line is the most commonly used and the same being the most controversial. In the following article different landmarks and its accuracy for orientating the occlusal plane in an edentulous subject as studied by various authors has been discussed.
Scattering of spinning test particles by gravitational plane waves
International Nuclear Information System (INIS)
Bini, D.; Gemelli, G.
1997-01-01
The authors study the motion of spinning particles in the gravitational plane-wave background and discuss particular solutions under a suitable choice of supplementary conditions. An analysis of the discontinuity of the motion across the wavefront is presented too
Metrical relationships in a standard triangle in an isotropic plane
Kolar-Šuper, R.; Kolar-Begović, Z.; Volenec, V.; Beban-Brkić, J.
2005-01-01
Each allowable triangle of an isotropic plane can be set in a standard position, in which it is possible to prove geometric properties analytically in a simplified and easier way by means of the algebraic theory developed in this paper.
DC Polarographic and Plane Polarographic investigation of the ...
African Journals Online (AJOL)
Bheema
D.C., A.C. and Complex Plane Polarographic behavior of copper (II) in monoethanolamine /sodium ... The Cd of supporting electrolyte can be directly measured. Theoretical phase sensitive ..... The mass and drop time of mercury are provided ...
Detection of plane, poorly oriented wide flaws using focused transducers
International Nuclear Information System (INIS)
Vadder, D. de; Azou, P.; Bastien, P.; Saglio, R.
1976-01-01
The detection of plane, poorly oriented, wide flaws by ultrasonic non destructive testing is distinctly improved when using focused transducers. An increased echo can be obtained crossing the defect limit [fr
innovative strategies on teaching plane geometry using geogebra ...
African Journals Online (AJOL)
It was recommended that enough mathematics software in schools especially .... Education Board Statistics for 2013/2014. Session). Two (2) .... Dependent Variable: Post-test score on Mathematics plane geometry using GeoGebra application.
Crossed-Plane Imaging of Premixed Turbulent Combustion Processes
National Research Council Canada - National Science Library
Gouldin, F
2003-01-01
.... Rayleigh scattering from premixed flames can be used for temperature imaging, and we have developed crossed-plane Rayleigh imaging in order to measure with high-resolution instantaneous temperature...
Can plane wave modes be physical modes in soliton models?
International Nuclear Information System (INIS)
Aldabe, F.
1995-08-01
I show that plane waves may not be used as asymptotic states in soliton models because they describe unphysical states. When asymptotic states are taken to the physical there is not T-matrix of O(1). (author). 9 refs
Mergers of elliptical galaxies and the fundamental plane
Gonzalez-Garcia, AC; van Albada, TS; AvilaReese,; Firmani, C; Frenk, CS; Allen, YC
2003-01-01
N-body simulations have been carried out in order to explore the final state of elliptical galaxies after encounters and more expecifically whether the Fundamental Plane (FP hereafter) relation is affected by merging.
Regularized plane-wave least-squares Kirchhoff migration
Wang, Xin; Dai, Wei; Schuster, Gerard T.
2013-01-01
A Kirchhoff least-squares migration (LSM) is developed in the prestack plane-wave domain to increase the quality of migration images. A regularization term is included that accounts for mispositioning of reflectors due to errors in the velocity
On spin and matrix models in the complex plane
International Nuclear Information System (INIS)
Damgaard, P.H.; Heller, U.M.
1993-01-01
We describe various aspects of statistical mechanics defined in the complex temperature or coupling-constant plane. Using exactly solvable models, we analyse such aspects as renormalization group flows in the complex plane, the distribution of partition function zeros, and the question of new coupling-constant symmetries of complex-plane spin models. The double-scaling form of matrix models is shown to be exactly equivalent to finite-size scaling of two-dimensional spin systems. This is used to show that the string susceptibility exponents derived from matrix models can be obtained numerically with very high accuracy from the scaling of finite-N partition function zeros in the complex plane. (orig.)
Plane-wave Least-squares Reverse Time Migration
Dai, Wei; Schuster, Gerard T.
2012-01-01
convergence for least-squares migration even when the migration velocity is not completely accurate. To significantly reduce computation cost, linear phase shift encoding is applied to hundreds of shot gathers to produce dozens of planes waves. A
3D plane-wave least-squares Kirchhoff migration
Wang, Xin; Dai, Wei; Huang, Yunsong; Schuster, Gerard T.
2014-01-01
A three dimensional least-squares Kirchhoff migration (LSM) is developed in the prestack plane-wave domain to increase the quality of migration images and the computational efficiency. Due to the limitation of current 3D marine acquisition
DLCQ and plane wave matrix Big Bang models
Blau, Matthias; O'Loughlin, Martin
2008-09-01
We study the generalisations of the Craps-Sethi-Verlinde matrix big bang model to curved, in particular plane wave, space-times, beginning with a careful discussion of the DLCQ procedure. Singular homogeneous plane waves are ideal toy-models of realistic space-time singularities since they have been shown to arise universally as their Penrose limits, and we emphasise the role played by the symmetries of these plane waves in implementing the flat space Seiberg-Sen DLCQ prescription for these curved backgrounds. We then analyse various aspects of the resulting matrix string Yang-Mills theories, such as the relation between strong coupling space-time singularities and world-sheet tachyonic mass terms. In order to have concrete examples at hand, in an appendix we determine and analyse the IIA singular homogeneous plane wave - null dilaton backgrounds.
DLCQ and plane wave matrix Big Bang models
International Nuclear Information System (INIS)
Blau, Matthias; O'Loughlin, Martin
2008-01-01
We study the generalisations of the Craps-Sethi-Verlinde matrix big bang model to curved, in particular plane wave, space-times, beginning with a careful discussion of the DLCQ procedure. Singular homogeneous plane waves are ideal toy-models of realistic space-time singularities since they have been shown to arise universally as their Penrose limits, and we emphasise the role played by the symmetries of these plane waves in implementing the flat space Seiberg-Sen DLCQ prescription for these curved backgrounds. We then analyse various aspects of the resulting matrix string Yang-Mills theories, such as the relation between strong coupling space-time singularities and world-sheet tachyonic mass terms. In order to have concrete examples at hand, in an appendix we determine and analyse the IIA singular homogeneous plane wave - null dilaton backgrounds.
Regularized plane-wave least-squares Kirchhoff migration
Wang, Xin
2013-09-22
A Kirchhoff least-squares migration (LSM) is developed in the prestack plane-wave domain to increase the quality of migration images. A regularization term is included that accounts for mispositioning of reflectors due to errors in the velocity model. Both synthetic and field results show that: 1) LSM with a reflectivity model common for all the plane-wave gathers provides the best image when the migration velocity model is accurate, but it is more sensitive to the velocity errors, 2) the regularized plane-wave LSM is more robust in the presence of velocity errors, and 3) LSM achieves both computational and IO saving by plane-wave encoding compared to shot-domain LSM for the models tested.
Transversus abdominis plane block: a cadaveric and radiological evaluation.
LENUS (Irish Health Repository)
McDonnell, John G
2011-04-11
The abdominal wall is a significant source of pain after abdominal surgery. Anterior abdominal wall analgesia may assist in improving postoperative analgesia. We have recently described a novel approach to block the abdominal wall neural afferents via the bilateral lumbar triangles of Petit, which we have termed a transversus abdominis plane block. The clinical efficacy of the transversus abdominis plane block has recently been demonstrated in a randomized controlled clinical trial of adults undergoing abdominal surgery.
Role of moving planes and moving spheres following Dupin cyclides
Jia, Xiaohong
2014-03-01
We provide explicit representations of three moving planes that form a μ-basis for a standard Dupin cyclide. We also show how to compute μ-bases for Dupin cyclides in general position and orientation from their implicit equations. In addition, we describe the role of moving planes and moving spheres in bridging between the implicit and rational parametric representations of these cyclides. © 2014 Elsevier B.V.
Diffraction by a plane angular sector, a new derivation
DEFF Research Database (Denmark)
Hansen, Thokild B.
1990-01-01
An alternative derivation is given for the exact solution to the scattering problem in which a Hertz dipole illuminates a perfectly conducting plane angular sector. Specifically, the Ohm-Rayleigh method is used rather than that of Satterwhite (1969)......An alternative derivation is given for the exact solution to the scattering problem in which a Hertz dipole illuminates a perfectly conducting plane angular sector. Specifically, the Ohm-Rayleigh method is used rather than that of Satterwhite (1969)...
Locating a circle on the plane using the minimax criterion
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Schoebel, Anita
2006-01-01
We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed.......We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed....
Apodised aperture using rotation of plane of polarization
International Nuclear Information System (INIS)
Simmons, W.W.; Leppelmeier, G.W.; Johnson, B.C.
1975-01-01
An apodised aperture based on the rotation of plane of polarization producing desirable characteristics on a transmitted light beam such as beam profiling in high flux laser amplifier chains is described. The apodised aperture is made with a lossless element by using one or more polarizers and/or analyzers and magneto-optical Faraday means for selectively rotating the plane of polarized radiation over the cross section to effect the desired apodisation
Focal plane for the next generation of earth observation instruments
Pranyies, P.; Toubhans, I.; Badoil, B.; Tanguy, F.; Descours, Francis
2017-09-01
Sodern is the French focal plane provider for Earth Observation (EO) satellites. Since the 1980's, Sodern has played an active role first in the SPOT program. Within the two-spacecraft constellation Pleiades 1A/1B over the next years, Sodern introduced advanced technologies as Silicon Carbide (SiC) focal plane structure and multispectral strip filters dedicated to multiple-lines detectors.
Plane-wave scattering from half-wave dipole arrays
DEFF Research Database (Denmark)
Jensen, Niels E.
1970-01-01
A matrix equation for determination of plane-wave scattering from arrays of thin short-circuited dipoles of lengths about half a wavelength is derived. Numerical and experimental results are presented for linear, circular, and concentric circular arrays.......A matrix equation for determination of plane-wave scattering from arrays of thin short-circuited dipoles of lengths about half a wavelength is derived. Numerical and experimental results are presented for linear, circular, and concentric circular arrays....
Tunnelling of plane waves through a square barrier
Energy Technology Data Exchange (ETDEWEB)
Julve, J [IMAFF, Consejo Superior de Investigaciones CientIficas, Serrano 113 bis, Madrid 28006 (Spain); UrrIes, F J de [Departamento de Fisica, Universidad de Alcala de Henares, Alcala de Henares, Madrid (Spain)], E-mail: julve@imaff.cfmac.csic.es, E-mail: fernando.urries@uah.es
2008-08-01
The time evolution of plane waves in the presence of a one-dimensional square quantum barrier is considered. Comparison is made between the cases of an infinite and a cut-off (shutter) initial plane wave. The difference is relevant when the results are applied to the analysis of the tunnelling regime. This work is focused on the analytical calculation of the time-evolved solution and highlights the contribution of the resonant (Gamow) states.
In-plane fluidelastic instability analysis for large steam generators
International Nuclear Information System (INIS)
Mureithi, Njuki; Olala, Stephen; Hadji, Abdallah
2015-01-01
Fluidelastic instability remains the most important vibration excitation mechanism in nuclear steam generators (SGs). Design guidelines, aimed at eliminating the possibility of fluidelastic instability, have been developed over the past 40 years. The design guidelines, based on the Connors equation, depend on a large database on cross-flow fluidelastic instability i.e. instability in the direction transverse to the flow. Past experience had shown that for an axi-symmetrically flexible tube, instability generally occurred in the transverse direction, at least at first. Although often not explicitly stated, there has been an implicit assumption that the in-plane direction was either stable, or would only suffer instability at velocities significantly higher than the transverse direction. This explains why SGs are fitted with anti-vibrations bars (AVBs) to mitigate transverse (out-of-plane) vibrations with no equivalent consideration for potential in-plane instability. This 'oversight' recently came to a head when SG at the San-Onofre NPP suffered in-plane fluidelastic instability. The present paper addresses the question of in-plane fluidelastic instability in large SGs. A historical review is presented to explain why this potential problem was left unresolved (or ignored) over the past 40+ years, and why engineers got away with it - at least until recently. Following the review, some recent work on in-plane fluidelastic instability modeling, using the quasi-steady model is presented. It is shown that in-plane fluidelastic instability can be fully modelled using this approach. The model results are used to propose some changes to existing design guidelines to cover the case of in-plane fluidelastic instability. (author)
Role of moving planes and moving spheres following Dupin cyclides
Jia, Xiaohong
2014-01-01
We provide explicit representations of three moving planes that form a μ-basis for a standard Dupin cyclide. We also show how to compute μ-bases for Dupin cyclides in general position and orientation from their implicit equations. In addition, we describe the role of moving planes and moving spheres in bridging between the implicit and rational parametric representations of these cyclides. © 2014 Elsevier B.V.
Data-plane Defenses against Routing Attacks on Tor
Directory of Open Access Journals (Sweden)
Tan Henry
2016-10-01
Full Text Available Tor is susceptible to traffic correlation attacks in which an adversary who observes flows entering and leaving the anonymity network can apply statistical techniques to correlate flows and de-anonymize their endpoints. While an adversary may not be naturally positioned to conduct such attacks, a recent study shows that the Internet’s control-plane can be manipulated to increase an adversary’s view of the network, and consequently, improve its ability to perform traffic correlation. This paper explores, in-depth, the effects of control-plane attacks on the security of the Tor network. Using accurate models of the live Tor network, we quantify Tor’s susceptibility to these attacks by measuring the fraction of the Tor network that is vulnerable and the advantage to the adversary of performing the attacks. We further propose defense mechanisms that protect Tor users from manipulations at the control-plane. Perhaps surprisingly, we show that by leveraging existing trust anchors in Tor, defenses deployed only in the data-plane are sufficient to detect most control-plane attacks. Our defenses do not assume the active participation of Internet Service Providers, and require only very small changes to Tor. We show that our defenses result in a more than tenfold decrease in the effectiveness of certain control-plane attacks.
Thermomechanical architecture of the VIS focal plane for Euclid
International Nuclear Information System (INIS)
Martignac, Jerome; Carty, Michael; Tourette, Thierry; Bachet, Damien; Berthe, Michel; Augueres, Jean-Louis; Amiaux, Jerome; Fontignie, Jean; Horeau, Benoit; Renaud, Diana
2014-01-01
One of the main challenges for current and near future space experiments is the increase of focal plane complexity in terms of amount of pixels. In the frame work of the ESA Euclid mission to be launched in 2020, the Euclid Consortium is developing an extremely large and stable focal plane for the VIS instrument. CEA has developed the thermomechanical architecture of that Focal Plane taking into account all the very stringent performance and mission related requirements. The VIS Focal Plane Assembly integrates 36 CCDs (operated at 150 K) connected to their front end electronics (operated at 280 K) as to obtain one of the largest focal plane (0.6 billion pixels) ever built for space application after the GAIA one. The CCDs are CCD273 type specially designed and provided by the e2v company under ESA contract, front end electronics is studied and provided by MSSL. In this paper we first recall the specific requirements that have driven the overall architecture of the VIS-FPA and especially the solutions proposed to cope with the scientific needs of an extremely stable focal plane, both mechanically and thermally. The mechanical structure based on SiC material used for the cold sub assembly supporting the CCDs is detailed. We describe also the modular architecture concept that we have selected taking into account AIT-AIV and programmatic constraints. (authors)
A zonal wavefront sensor with multiple detector planes
Pathak, Biswajit; Boruah, Bosanta R.
2018-03-01
A conventional zonal wavefront sensor estimates the wavefront from the data captured in a single detector plane using a single camera. In this paper, we introduce a zonal wavefront sensor which comprises multiple detector planes instead of a single detector plane. The proposed sensor is based on an array of custom designed plane diffraction gratings followed by a single focusing lens. The laser beam whose wavefront is to be estimated is incident on the grating array and one of the diffracted orders from each grating is focused on the detector plane. The setup, by employing a beam splitter arrangement, facilitates focusing of the diffracted beams on multiple detector planes where multiple cameras can be placed. The use of multiple cameras in the sensor can offer several advantages in the wavefront estimation. For instance, the proposed sensor can provide superior inherent centroid detection accuracy that can not be achieved by the conventional system. It can also provide enhanced dynamic range and reduced crosstalk performance. We present here the results from a proof of principle experimental arrangement that demonstrate the advantages of the proposed wavefront sensing scheme.
3D plane-wave least-squares Kirchhoff migration
Wang, Xin
2014-08-05
A three dimensional least-squares Kirchhoff migration (LSM) is developed in the prestack plane-wave domain to increase the quality of migration images and the computational efficiency. Due to the limitation of current 3D marine acquisition geometries, a cylindrical-wave encoding is adopted for the narrow azimuth streamer data. To account for the mispositioning of reflectors due to errors in the velocity model, a regularized LSM is devised so that each plane-wave or cylindrical-wave gather gives rise to an individual migration image, and a regularization term is included to encourage the similarities between the migration images of similar encoding schemes. Both synthetic and field results show that: 1) plane-wave or cylindrical-wave encoding LSM can achieve both computational and IO saving, compared to shot-domain LSM, however, plane-wave LSM is still about 5 times more expensive than plane-wave migration; 2) the regularized LSM is more robust compared to LSM with one reflectivity model common for all the plane-wave or cylindrical-wave gathers.
Off-plane x-ray reflection grating fabrication
Peterson, Thomas J.; DeRoo, Casey T.; Marlowe, Hannah; McEntaffer, Randall L.; Miles, Drew M.; Tutt, James H.; Schultz, Ted B.
2015-09-01
Off-plane X-ray diffraction gratings with precision groove profiles at the submicron scale will be used in next generation X-ray spectrometers. Such gratings will be used on a current NASA suborbital rocket mission, the Off-plane Grating Rocket Experiment (OGRE), and have application for future grating missions. The fabrication of these gratings does not come without challenges. High performance off-plane gratings must be fabricated with precise radial grating patterns, optically at surfaces, and specific facet angles. Such gratings can be made using a series of common micro-fabrication techniques. The resulting process is highly customizable, making it useful for a variety of different mission architectures. In this paper, we detail the fabrication method used to produce high performance off-plane gratings and report the results of a preliminary qualification test of a grating fabricated in this manner. The grating was tested in the off-plane `Littrow' configuration, for which the grating is most efficient for a given diffraction order, and found to achieve 42% relative efficiency in the blaze order with respect to all diffracted light.
On deformation of complex continuum immersed in a plane space
Kovalev, V. A.; Murashkin, E. V.; Radayev, Y. N.
2018-05-01
The present paper is devoted to mathematical modelling of complex continua deformations considered as immersed in an external plane space. The complex continuum is defined as a differential manifold supplied with metrics induced by the external space. A systematic derivation of strain tensors by notion of isometric immersion of the complex continuum into a plane space of a higher dimension is proposed. Problem of establishing complete systems of irreducible objective strain and extrastrain tensors for complex continuum immersed in an external plane space is resolved. The solution to the problem is obtained by methods of the field theory and the theory of rational algebraic invariants. Strain tensors of the complex continuum are derived as irreducible algebraic invariants of contravariant vectors of the external space emerging as functional arguments in the complex continuum action density. Present analysis is restricted to rational algebraic invariants. Completeness of the considered systems of rational algebraic invariants is established for micropolar elastic continua. Rational syzygies for non-quadratic invariants are discussed. Objective strain tensors (indifferent to frame rotations in the external plane space) for micropolar continuum are alternatively obtained by properly combining multipliers of polar decompositions of deformation and extra-deformation gradients. The latter is realized only for continua immersed in a plane space of the equal mathematical dimension.
The geometry of plane waves in spaces of constant curvature
International Nuclear Information System (INIS)
Tran, H.V.
1988-01-01
We examined the geometry of possible plane wave fronts in spaces of constant curvature for three cases in which the cosmological constant is positive, zero, or negative. The cosmological constant and a second-order invariant determined by a congruence of null rays were used in the investigation. We embedded the spaces under investigation in a flat five-dimensional space, and studied the null hyperplanes passing through the origin of the flat five-dimensional space. The embedded spaces are represented by quadrics in the five-dimensional space. The plane wave fronts are represented by the intersection of the quadric with null hyperplanes passing through the origin of the five-dimensional space. We concluded that in Minkowski spaces (zero cosmological constant), the plane-fronted waves will intersect if and only if the second-order invariant mentioned above is non-zero. For deSitter spaces (positive cosmological constant), plane-fronted waves will always intersect. For anti-deSitter spaces (negative cosmological constant), plane-fronted waves may but need not intersect
A differentiated plane wave: its passage through a slab
International Nuclear Information System (INIS)
Hannay, J H; Nye, J F
2013-01-01
Differentiating a monochromatic uniform plane electromagnetic wavefield with respect to its direction produces, from a field that is completely lacking in localized specific features, one that contains a straight vortex-like line, a ‘C-line’ of defined circular polarization. There is also a second separate C-line of opposite handedness; indeed, in a sense, a straight line of every polarization is realized. Because of its primitive construction it is analytically simple to study the passage of a differentiated wave obliquely through a plane interface into a medium of different refractive index, to trace its C-line. This was done in an earlier paper. Here we extend the method to passage through a parallel-sided transparent slab. There are multiple reflections within the slab, as in a Fabry–Pérot interferometer. The exiting wave, as a single differentiated plane wave, has a straight oblique C-line. Inside the slab, and in front of it, there is wave interference. The result is a coiled, helix-like, C-line in front of the slab and another inside it. The two coils wrap around separate hyperboloids of one sheet, like cooling towers. The emerging straight C-line is shifted (with respect to a C-line in a notional undisturbed incident plane wave) both in the plane of incidence and transversely to it, and the second C-line behaves similarly. The analysis is exact and could be extended in a straightforward way to a general stratified medium. (paper)
Designing broad phononic band gaps for in-plane modes
Li, Yang Fan; Meng, Fei; Li, Shuo; Jia, Baohua; Zhou, Shiwei; Huang, Xiaodong
2018-03-01
Phononic crystals are known as artificial materials that can manipulate the propagation of elastic waves, and one essential feature of phononic crystals is the existence of forbidden frequency range of traveling waves called band gaps. In this paper, we have proposed an easy way to design phononic crystals with large in-plane band gaps. We demonstrated that the gap between two arbitrarily appointed bands of in-plane mode can be formed by employing a certain number of solid or hollow circular rods embedded in a matrix material. Topology optimization has been applied to find the best material distributions within the primitive unit cell with maximal band gap width. Our results reveal that the centroids of optimized rods coincide with the point positions generated by Lloyd's algorithm, which deepens our understandings on the formation mechanism of phononic in-plane band gaps.
Cutting solid figures by plane - analytical solution and spreadsheet implementation
Benacka, Jan
2012-07-01
In some secondary mathematics curricula, there is a topic called Stereometry that deals with investigating the position and finding the intersection, angle, and distance of lines and planes defined within a prism or pyramid. Coordinate system is not used. The metric tasks are solved using Pythagoras' theorem, trigonometric functions, and sine and cosine rules. The basic problem is to find the section of the figure by a plane that is defined by three points related to the figure. In this article, a formula is derived that gives the positions of the intersection points of such a plane and the figure edges, that is, the vertices of the section polygon. Spreadsheet implementations of the formula for cuboid and right rectangular pyramids are presented. The user can check his/her graphical solution, or proceed if he/she is not able to complete the section.
Polarization sensitivity testing of off-plane reflection gratings
Marlowe, Hannah; McEntaffer, Randal L.; DeRoo, Casey T.; Miles, Drew M.; Tutt, James H.; Laubis, Christian; Soltwisch, Victor
2015-09-01
Off-Plane reflection gratings were previously predicted to have different efficiencies when the incident light is polarized in the transverse-magnetic (TM) versus transverse-electric (TE) orientations with respect to the grating grooves. However, more recent theoretical calculations which rigorously account for finitely conducting, rather than perfectly conducting, grating materials no longer predict significant polarization sensitivity. We present the first empirical results for radially ruled, laminar groove profile gratings in the off-plane mount which demonstrate no difference in TM versus TE efficiency across our entire 300-1500 eV bandpass. These measurements together with the recent theoretical results confirm that grazing incidence off-plane reflection gratings using real, not perfectly conducting, materials are not polarization sensitive.
Projecting non-diffracting waves with intermediate-plane holography.
Mondal, Argha; Yevick, Aaron; Blackburn, Lauren C; Kanellakopoulos, Nikitas; Grier, David G
2018-02-19
We introduce intermediate-plane holography, which substantially improves the ability of holographic trapping systems to project propagation-invariant modes of light using phase-only diffractive optical elements. Translating the mode-forming hologram to an intermediate plane in the optical train can reduce the need to encode amplitude variations in the field, and therefore complements well-established techniques for encoding complex-valued transfer functions into phase-only holograms. Compared to standard holographic trapping implementations, intermediate-plane holograms greatly improve diffraction efficiency and mode purity of propagation-invariant modes, and so increase their useful non-diffracting range. We demonstrate this technique through experimental realizations of accelerating modes and long-range tractor beams.
Flow of Dense Granular Suspensions on an Inclined Plane
Bonnoit, C.; Lanuza, J.; Lindner, A.; Clément, E.
2008-07-01
We investigate the flow behavior of dense granular suspensions, by the use of an inclined plane. The suspensions are prepared at high packing fractions and consist of spherical non-Brownian particles density matched with the suspending fluid. On the inclined plane, we perform a systematic study of the surface velocity as a function of the layer thickness for various flow rates and tilt angles. We perform measurements on a classical rheometer (parallel-plate rheometer) that is shown to be in good agreement with existing models, up to a volume fraction of 50%. Comparing these results, we show that the flow on an inclined plane can, up to a volume fraction of 50%, indeed be described by a purely viscous model in agreement with the results from classical rheometry.
Thermal properties of self-gravitating plane-symmetric configuration
Energy Technology Data Exchange (ETDEWEB)
Hara, T; Ikeuchi, S [Kyoto Univ. (Japan). Dept. of Physics; Sugimoto, D
1976-09-01
As a limiting case of rotating stars, thermal properties of infinite plane-symmetric self-gravitating gas are investigated. Such a configuration is characterized by surface density of the plane instead of stellar mass. In the Kelvin contraction, temperature of the interior decreases, if the surface density is kept constant. If the accretion of matter takes place, or if the angular momenta are transferred outward, the surface density will increase. In this case, the temperature of the interior may increase. When a nuclear burning is ignited, it is thermally unstable in most cases, even when electrons are non-degenerate. This thermal instability is one of the essential differences of the plane-symmetric configuration from the spherical star. Such instabilities are computed for different cases of nuclear fuels. This type of nuclear instability is the same phenomenon as thermal instability of a thin shell burning in a spherical star.
Measure Guideline: Guidance on Taped Insulating Sheathing Drainage Planes
Energy Technology Data Exchange (ETDEWEB)
Grin, A. [Building Science Corporation, Somerville, MA (United States); Lstiburek, J. [Building Science Corporation, Somerville, MA (United States)
2014-09-01
The goal of this research is to provide durable and long-term water management solutions using exterior insulating sheathing as part of the water management system. It is possible to tape or seal the joints in insulating sheathing to create a drainage plane and even an air control layer. There exists the material durability component of the tape as well as the system durability component being the taped insulating sheathing as the drainage plane. This measure guideline provides best practice and product recommendations from the interviewed contractors and homebuilders who collectively have a vast amount of experience. Three significant issues were discussed with the group, which are required to make taped insulating sheathing a simple, long-term, and durable drainage plane: horizontal joints should be limited or eliminated wherever possible; where a horizontal joint exists use superior materials; and frequent installation inspection and regular trade training are required to maintain proper installation.
Apparatus and methods for memory using in-plane polarization
Liu, Junwei; Chang, Kai; Ji, Shuai-Hua; Chen, Xi; Fu, Liang
2018-05-01
A memory device includes a semiconductor layer with an in-plane polarization component switchable between a first direction and a second direction. A writing electrode is employed to apply a writing voltage to the semiconductor layer to change the in-plane polarization component between the first direction and the second direction. A reading electrode is employed to apply a reading voltage to the semiconductor layer to measure a tunneling current substantially perpendicular to the polarization direction of the in-plane polarization component. The directions of the reading voltage and the writing voltage are substantially perpendicular to each other. Therefore, the reading process is non-destructive. Thin films (e.g., one unit cell thick) of ferroelectric material can be used in the memory device to increase the miniaturization of the device.
Laplace plane modifications arising from solar radiation pressure
Energy Technology Data Exchange (ETDEWEB)
Rosengren, Aaron J.; Scheeres, Daniel J., E-mail: aaron.rosengren@colorado.edu [ADepartment of Aerospace Engineering Sciences, University of Colorado at Boulder, Boulder, CO 80309 (United States)
2014-05-01
The dynamical effects of solar radiation pressure (SRP) in the solar system have been rigorously studied since the early 1900s. This non-gravitational perturbation plays a significant role in the evolution of dust particles in circumplanetary orbits, as well as in the orbital motion about asteroids and comets. For gravitationally dominated orbits, SRP is negligible and the resulting motion is largely governed by the oblateness of the primary and the attraction of the Sun. The interplay between these gravitational perturbations gives rise to three mutually perpendicular planes of equilibrium for circular satellite orbits. The classical Laplace plane lies between the equatorial and orbital planes of the primary, and is the mean reference plane about whose axis the pole of a satellite's orbit precesses. From a previously derived solution for the secular motion of an orbiter about a small body in a SRP dominated environment, we find that SRP acting alone will cause an initially circular orbit to precess around the pole of the primary's heliocentric orbital plane. When the gravitational and non-gravitational perturbations act in concert, the resulting equilibrium planes turn out to be qualitatively different, in some cases, from those obtained without considering the radiation pressure. The warping of the surfaces swept out by the modified equilibria as the semi-major axis varies depends critically on the cross-sectional area of the body exposed. These results, together with an adiabatic invariance argument on Poynting-Robertson drag, provide a natural qualitative explanation for the initial albedo dichotomy of Saturn's moon, Iapetus.
Dynamics of plane-symmetric thin walls in general relativity
International Nuclear Information System (INIS)
Wang, A.
1992-01-01
Plane walls (including plane domain walls) without reflection symmetry are studied in the framework of Einstein's general relativity. Using the distribution theory, all the Einstein field equations and Bianchi identities are split into two groups: one holding in the regions outside of the wall and the other holding at the wall. The Einstein field equations at the wall are found to take a very simple form, and given explicitly in terms of the discontinuities of the metric coefficients and their derivatives. The Bianchi identities at the wall are also given explicitly. Using the latter, the interaction of a plane wall with gravitational waves and some specific matter fields is studied. In particular, it is found that, when a gravitational plane wave passes through a wall, if the wall has no reflection symmetry, the phenomena, such as reflection, stimulation, or absorption, in general, occur. It is also found that, unlike for gravitational waves, a massless scalar wave or an electromagnetic wave continuously passes through a wall without any reflection. The repulsion and attraction of a plane wall are also studied. It is found that the acceleration of an observer who is at rest relative to the wall usually consists of three parts: one is due to the force produced by the wall, the second is due to the force produced by the space-time curvature, which is zero if the wall has reflection symmetry, and the last is due to the accelerated motion of the wall. As a result, a repulsive (attractive) plane wall may not be repulsive (attractive) at all. Finally, the collision and interaction among the walls are studied
Massie, Mark A.; Woolaway, James T., II; Curzan, Jon P.; McCarley, Paul L.
1993-08-01
An infrared focal plane has been simulated, designed and fabricated which mimics the form and function of the vertebrate retina. The `Neuromorphic' focal plane has the capability of performing pixel-based sensor fusion and real-time local contrast enhancement, much like the response of the human eye. The device makes use of an indium antimonide detector array with a 3 - 5 micrometers spectral response, and a switched capacitor resistive network to compute a real-time 2D spatial average. This device permits the summation of other sensor outputs to be combined on-chip with the infrared detections of the focal plane itself. The resulting real-time analog processed information thus represents the combined information of many sensors with the advantage that analog spatial and temporal signal processing is performed at the focal plane. A Gaussian subtraction method is used to produce the pixel output which when displayed produces an image with enhanced edges, representing spatial and temporal derivatives in the scene. The spatial and temporal responses of the device are tunable during operation, permitting the operator to `peak up' the response of the array to spatial and temporally varying signals. Such an array adapts to ambient illumination conditions without loss of detection performance. This paper reviews the Neuromorphic infrared focal plane from initial operational simulations to detailed design characteristics, and concludes with a presentation of preliminary operational data for the device as well as videotaped imagery.
International Nuclear Information System (INIS)
Inamura, T.; Kim, H.Y.; Hosoda, H.; Miyazaki, S.
2013-01-01
Highlights: ► Kinematic compatibility (KC) among martensite variants in Ti-Nb-Al is evaluated. ► Rotation Q is necessary to keep KC at any junction plane (JP). ► The rotation Q is equivalent to the rotation to form the exact twin-relationship. ► The JP preferentially observed in experiment is the JP with the smaller Q. ► We propose two preferential JPs with {1 1 1} type I and 〈2 1 1〉 type II twin in Ti-Nb-Al. -- Abstract: The invariant plane (IP) condition at a habit plane (HP) and the kinematic compatibility (KC) condition at a junction plane (JP) are quantitatively evaluated by the geometrically nonlinear theory of martensite and the origin of the twin orientation relationship (OR) at a JP is revealed in a β titanium shape memory alloy. Exact twin OR at a JP is impossible among the habit plane variants (HPVs). A nonzero rotation is necessary to maintain the compatibility at a JP between the HPVs. The fully compatible HPV cluster in which IP at a HP and KC at a JP are maintained simultaneously is impossible in this alloy. However, it was found that twin OR and KC can be maintained simultaneously. The preferentially observed HPV clusters in transmission electron microscopy are the clusters with a smaller rotation to maintain KC at a JP
International Nuclear Information System (INIS)
Wei, Hsin-Yu; Qiu, Chang-Hua; Soleimani, Manuchehr
2015-01-01
Electrical capacitance tomography (ECT) is a non-invasive imaging technique that is sensitive to the dielectric permittivity property of an object. Conventional ECT systems have a circular/cylindrical or rectangular geometry, in which the electrode plates are usually spaced equally around the tank. It is the most common configuration as it can be easily applied to industrial pipelines. However, under some circumstances, the full access to the imaging geometry may not be applicable due to the limitation of the process area. In those cases, and with limited access, planar ECT sensors can fit the process structure if access to only one side is possible. A single-plane ECT configuration has been proposed for such applications. However, the planar array often suffers from a lack of sensitivity and difficulty with depth detection. To better understand these limitations we investigate the imaging performance from the single-plane ECT to dual-plane ECT structure. The limitations and constraints of the planar configuration will also be discussed. Several experiments were conducted using both single-plane and dual-plane configurations to evaluate the potential applications. The initial results are promising, and the quality of the reconstructed images are compared with the real condition for process validation. (paper)
Inductance calculation of 3D superconducting structures with ground plane
International Nuclear Information System (INIS)
Teh, C.H.; Kitagawa, M.; Okabe, Y.
1999-01-01
An inductance calculation method, which is based on calculating the current distribution of a fluxoid-trapped superconducting loop by using the expression of momentum and the Maxwell equations, is reconstructed to enable calculation of arbitrary 3D structures which have a ground plane (GP). Calculation of the mutual inductances of the superconductor system is also incorporated into the algorithm. The method of images is used to save computational resources, and the mirror plane is demonstrated to be just at the effective penetration depth below the upper boundary of the GP. The algorithm offers accurate results with reasonable calculation time. (author)
The Groenewold-Moyal Plane and its Quantum Physics
International Nuclear Information System (INIS)
Balachandran, A. P.; Padmanabhan, Pramod
2009-01-01
Quantum theories constructed on the noncommutative spacetime called the Groenewold-Moyal(GM) plane exhibit many interesting properties such as causality violation, Lorentz and CPT non-invariance and twisted statistics. Such violations lead to many striking features that may be tested experimentally. Thus these theories predict Pauli-forbidden transitions due to twisted statistics, anisotropies and acausal effects in the cosmic microwave background radiation in correlations of observables and Lorentz and CPT violations in scattering amplitudes. Such features of quantum physics on the GM plane are surveyed in this review.
Plane waves and spherical means applied to partial differential equations
John, Fritz
2004-01-01
Elementary and self-contained, this heterogeneous collection of results on partial differential equations employs certain elementary identities for plane and spherical integrals of an arbitrary function, showing how a variety of results on fairly general differential equations follow from those identities. The first chapter deals with the decomposition of arbitrary functions into functions of the type of plane waves. Succeeding chapters introduce the first application of the Radon transformation and examine the solution of the initial value problem for homogeneous hyperbolic equations with con
Dynamics of polynomials in finite and infinite Benz planes
Rafael Artzy
1992-01-01
The classical Benz planes, that is, Möbius, Minkowski, and Laguerre planes, can be coordinatized [cf. 1], respectively, by the field C of complex numbers, the ring of “double numbers” z=x+jy (x,y ∊ R) where an element j not in R, with j2=1 is adjoined, and the ring of “dual numbers” z=x+ye where an element e not in R with e2=0 is adjoined to R. When the field R is replaced by another field, in our case finite prime fields Fp (p a prime), one also obtains co...
Vertical-Cavity In-plane Heterostructures: Physics and Applications
DEFF Research Database (Denmark)
Taghizadeh, Alireza; Mørk, Jesper; Chung, Il-Sug
2015-01-01
We show that the in-plane heterostructures realized in vertical cavities with high contrast grating(HCG) reflector enables exotic configurations of heterostructure and photonic wells. In photonic crystal heterostructures forming a photonic well, the property of a confined mode is determined...... by the well width and barrier height. We show that in vertical-cavity in-plane heterostructures, anisotropic dispersion curvatures plays a key role as well, leading to exotic effects such as a photonic well with conduction band like well and a valence band like barrier. We investigate three examples...
Exploring plane-symmetric solutions in f(R) gravity
Energy Technology Data Exchange (ETDEWEB)
Shamir, M. F., E-mail: farasat.shamir@nu.edu.pk [National University of Computer and Emerging Sciences, Department of Sciences and Humanities (Pakistan)
2016-02-15
The modified theories of gravity, especially the f(R) gravity, have attracted much attention in the last decade. This paper is devoted to exploring plane-symmetric solutions in the context of metric f(R) gravity. We extend the work on static plane-symmetric vacuum solutions in f(R) gravity already available in the literature [1, 2]. The modified field equations are solved using the assumptions of both constant and nonconstant scalar curvature. Some well-known solutions are recovered with power-law and logarithmic forms of f(R) models.
Plane waves and structures in turbulent channel flow
Sirovich, L.; Ball, K. S.; Keefe, L. R.
1990-01-01
A direct simulation of turbulent flow in a channel is analyzed by the method of empirical eigenfunctions (Karhunen-Loeve procedure, proper orthogonal decomposition). This analysis reveals the presence of propagating plane waves in the turbulent flow. The velocity of propagation is determined by the flow velocity at the location of maximal Reynolds stress. The analysis further suggests that the interaction of these waves appears to be essential to the local production of turbulence via bursting or sweeping events in the turbulent boundary layer, with the additional suggestion that the fast acting plane waves act as triggers.
Comb-Line Filter with Coupling Capacitor in Ground Plane
Directory of Open Access Journals (Sweden)
Toshiaki Kitamura
2011-01-01
Full Text Available A comb-line filter with a coupling capacitor in the ground plane is proposed. The filter consists of two quarter-wavelength microstrip resonators. A coupling capacitor is inserted into the ground plane in order to build strong coupling locally along the resonators. The filtering characteristics are investigated through numerical simulations as well as experiments. Filtering characteristics that have attenuation poles at both sides of the passband are obtained. The input susceptances of even and odd modes and coupling coefficients are discussed. The filters using stepped impedance resonators (SIRs are also discussed, and the effects of the coupling capacitor for an SIR structure are shown.
Plane-Wave Imaging Challenge in Medical Ultrasound
DEFF Research Database (Denmark)
Liebgott, Herve; Molares, Alfonso Rodriguez; Jensen, Jørgen Arendt
2016-01-01
for this effect, but comparing the different methods is difficult due to the lack of appropriate tools. PICMUS, the Plane-Wave Imaging Challenge in Medical Ultrasound aims to provide these tools. This paper describes the PICMUS challenge, its motivation, implementation, and metrics.......Plane-Wave imaging enables very high frame rates, up to several thousand frames per second. Unfortunately the lack of transmit focusing leads to reduced image quality, both in terms of resolution and contrast. Recently, numerous beamforming techniques have been proposed to compensate...
Combinatorics associated with inflections and bitangents of plane quartics
International Nuclear Information System (INIS)
Gizatullin, M Kh
2013-01-01
After a preliminary survey and a description of some small Steiner systems from the standpoint of the theory of invariants of binary forms, we construct a binary Golay code (of length 24) using ideas from J. Grassmann's thesis of 1875. One of our tools is a pair of disjoint Fano planes. Another application of such pairs and properties of plane quartics is a construction of a new block design on 28 objects. This block design is a part of a dissection of the set of 288 Aronhold sevens. The dissection distributes the Aronhold sevens into 8 disjoint block designs of this type
Hi-GAL: The Herschel Infrared Galactic Plane Survey
Molinari, S.; Swinyard, B.; Bally, J.; Barlow, M.; Bernard, J.-P.; Martin, P.; Moore, T.; Noriega-Crespo, A.; Plume, R.; Testi, L.; Zavagno, A.; Abergel, A.; Ali, B.; André, P.; Baluteau, J.-P.
2010-01-01
Hi-GAL, the Herschel infrared Galactic Plane Survey, is an Open Time Key Project of the Herschel Space Observatory. It will make an unbiased photometric survey of the inner Galactic plane by mapping a 2° wide strip in the longitude range ∣l∣ < 60° in five wavebands between 70 μm and 500 μm. The aim of Hi-GAL is to detect the earliest phases of the formation of molecular clouds and high-mass stars and to use the optimum combination of Herschel wavelength coverage, sensitivity, mapping strategy...
Problems of the orthogonalized plane wave method. 1
International Nuclear Information System (INIS)
Farberovich, O.V.; Kurganskii, S.I.; Domashevskaya, E.P.
1979-01-01
The main problems of the orthogonalized plane wave method are discussed including (a) consideration of core states; (b) effect of overlap of wave functions of external core states upon the band structure; (c) calculation of d-type states. The modified orthogonal plane wave method (MOPW method) of Deegan and Twose is applied in a general form to solve the problems of the usual OPW method. For the first time the influence on the spectrum of the main parameters of the MOPW method is studied systematically by calculating the electronic energy spectrum in the transition metals Nb and V. (author)
Pseudodifferential Analysis, Automorphic Distributions in the Plane and Modular Forms
Unterberger, Andre
2011-01-01
Pseudodifferential analysis, introduced in this book in a way adapted to the needs of number theorists, relates automorphic function theory in the hyperbolic half-plane I to automorphic distribution theory in the plane. Spectral-theoretic questions are discussed in one or the other environment: in the latter one, the problem of decomposing automorphic functions in I according to the spectral decomposition of the modular Laplacian gives way to the simpler one of decomposing automorphic distributions in R2 into homogeneous components. The Poincare summation process, which consists in building au
Locating a circle on the plane using the minimax criterion
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Schöbel, Anita
2009-01-01
We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circumference of the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed......We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circumference of the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed...
Geometric characteristics of aberrations of plane-symmetric optical systems
International Nuclear Information System (INIS)
Lu Lijun; Deng Zhiyong
2009-01-01
The geometric characteristics of aberrations of plane-symmetric optical systems are studied in detail with a wave-aberration theory. It is dealt with as an extension of the Seidel aberrations to realize a consistent aberration theory from axially symmetric to plane-symmetric systems. The aberration distribution is analyzed with the spot diagram of a ray and an aberration curve. Moreover, the root-mean-square value and the centroid of aberration distribution are discussed. The numerical results are obtained with the focusing optics of a toroidal mirror at grazing incidence.
Locating a general minisum 'circle' on a plane
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Körner, Mark-Christoph
2011-01-01
We approximate a set of given points in the plane by the boundary of a convex and symmetric set which is the unit circle of some norm. This generalizes previous work on the subject which considers Euclidean circles only. More precisely, we examine the problem of locating and scaling the unit circle...... of some given norm k with respect to given points on the plane such that the sum of weighted distances (as measured by the same norm k) between the circumference of the circle and the points is minimized. We present general results and are able to identify a finite dominating set in the case that k...
On the topology of real algebraic plane curves
DEFF Research Database (Denmark)
Cheng, Jinsan; Lazard, Sylvain; Peñaranda, Luis
2010-01-01
We revisit the problem of computing the topology and geometry of a real algebraic plane curve. The topology is of prime interest but geometric information, such as the position of singular and critical points, is also relevant. A challenge is to compute efficiently this information for the given...... and isolation with rational univariate representations. This has the advantage of avoiding computations with polynomials with algebraic coefficients, even in non-generic positions. Our algorithm isolates critical points in boxes and computes a decomposition of the plane by rectangular boxes. This decomposition...
A comprehensive model for in-plane and out-of-plane vibration of CANDU fuel endplate rings
Energy Technology Data Exchange (ETDEWEB)
Yu, S.D., E-mail: syu@ryerson.ca; Fadaee, M.
2016-08-01
Highlights: • Proposed an effective method for modelling bending and torsional vibration of CANDU fuel endplate rings. • Applied successfully the thick plate theory to curved structural members by accounting for the transverse shear effect. • The proposed method is computationally more efficient compared to the 3D finite element. - Abstract: In this paper, a comprehensive vibration model is developed for analysing in-plane and out-of-plane vibration of CANDU fuel endplate rings by taking into consideration the effects of in-plane extension in the circumferential and radial directions, shear, and rotatory inertia. The model is based on Reddy’s thick plate theory and the nine-node isoparametric Lagrangian plate finite elements. Natural frequencies of various modes of vibration of circular rings obtained using the proposed method are compared with 3D finite element results, experimental data and results available in the literature. Excellent agreement was achieved.
Dynamic photonic lightpaths in the StarPlane network
Grosso, P.; Marchal, D.; Maassen, J.; Bernier, E.; Xu, L.; de Laat, C.
2009-01-01
The StarPlane project enables users to dynamically control network photonic paths. Applications running on the Distributed ASCI Supercomputer (DAS-3) can manipulate wavelengths in the Dutch research and education network SURFnet6. The goal is to achieve fast switching times so that when the
In-plane laser forming for high precision alignment
Folkersma, Ger; Römer, Gerardus Richardus, Bernardus, Engelina; Brouwer, Dannis Michel; Huis in 't Veld, Bert
2014-01-01
Laser microforming is extensively used to align components with submicrometer accuracy, often after assembly. While laser-bending sheet metal is the most common laser-forming mechanism, the in-plane upsetting mechanism is preferred when a high actuator stiffness is required. A three-bridge planar
A 1.3 giga pixels focal plane for GAIA
Laborie, Anouk; Pouny, Pierre; Vetel, Cyril; Collados, Emmanuel; Rougier, Gilles; Davancens, Robert; Zayer, Igor; Perryman, Michael; Pace, Oscar
2004-06-01
The astrometric mission GAIA is a cornerstone mission of the European Space Agency, due for launch in the 2010 time frame. Requiring extremely demanding performance GAIA calls for the development of an unprecedented large focal plane featuring innovative technologies. For securing the very challenging GAIA development, a significant number of technology activities have been initiated by ESA through a competitive selection process. In this context, an industrial consortium led by EADS-Astrium (France) with e2v technologies (UK) as major subcontractor was selected for the GAIA CCD and Focal Plane Technology Demonstrators programme, which is by far the most significant and the most critical GAIA pre-development for all aspects: science performance, development schedule and cost. This programme has started since August 2002 and will end early 2005 prior to commencement of the GAIA Phase B. While the GAIA payload will host three instruments and related focal planes, the major mission objectives are assigned to the Astrometric (ASTRO) Focal Plane, which is the subject of this presentation.
Balanced partitions of 3-colored geometric sets in the plane
Bereg, S.; Hurtado, F.; Kano, M.; Korman, M.; Lara, D.; Seara, C.; Silveira, R.I.; Urrutia, J.; Verbeek, K.A.B.
2015-01-01
Let SS be a finite set of geometric objects partitioned into classes or colors . A subset S'¿SS'¿S is said to be balanced if S'S' contains the same amount of elements of SS from each of the colors. We study several problems on partitioning 33-colored sets of points and lines in the plane into two
Reconstruction of Galileo Galilei's Experiment: The Inclined Plane
Straulino, S.
2008-01-01
In the "Third Day" of the "Discourses and Mathematical Demonstrations Concerning Two New Sciences" Galileo Galilei describes the famous experiment of the inclined plane and uses it to bring an experimental confirmation to the laws of uniformly accelerated motion. We describe a reconstruction of the experiment and how the results can be used for…
Fisher-Renyi entropy product and information plane
International Nuclear Information System (INIS)
Romera, E.; Nagy, A.
2008-01-01
Connection between Fisher information and Renyi entropy has been established. This link allows us to define the Fisher-Renyi information plane and an entropic product in terms of these quantities. New Renyi uncertainty relations are obtained for single particle densities of many particle systems in position-momentum conjugate spaces
Technique for measurements of plane waves of uniaxial strain
International Nuclear Information System (INIS)
Graham, R.A.
1977-01-01
The measurement of plane waves in uniaxial strain, in which large surface areas are loaded and the measurements are restricted to a central region that is not influenced by lateral boundaries, is discussed. Measuring techniques are covered and instruments are discussed
Axial and focal-plane diffraction catastrophe integrals
International Nuclear Information System (INIS)
Berry, M V; Howls, C J
2010-01-01
Exact expressions in terms of Bessel functions are found for some of the diffraction catastrophe integrals that decorate caustics in optics and mechanics. These are the axial and focal-plane sections of the elliptic and hyperbolic umbilic diffraction catastrophes, and symmetric elliptic and hyperbolic unfoldings of the X 9 diffraction catastrophes. These representations reveal unexpected relations between the integrals.
Refining the fundamental plane of accreting black holes
Körding, E.; Falcke, H.D.E.; Corbel, S.; K�rding, E.
2006-01-01
Context: .The idea of a unified description of supermassive and stellar black holes has been supported by the extension of the empirical radio/X-ray correlation from X-ray binaries to active galactic nuclei through the inclusion of a mass term. This has lead to the so-called fundamental plane of
Modelling the Landing of a Plane in a Calculus Lab
Morante, Antonio; Vallejo, Jose A.
2012-01-01
We exhibit a simple model of a plane landing that involves only basic concepts of differential calculus, so it is suitable for a first-year calculus lab. We use the computer algebra system Maxima and the interactive geometry software GeoGebra to do the computations and graphics. (Contains 5 figures and 1 note.)
Pascal’s Theorem in Real Projective Plane
Coghetto Roland
2017-01-01
In this article we check, with the Mizar system [2], Pascal’s theorem in the real projective plane (in projective geometry Pascal’s theorem is also known as the Hexagrammum Mysticum Theorem)1. Pappus’ theorem is a special case of a degenerate conic of two lines.
Pascal’s Theorem in Real Projective Plane
Directory of Open Access Journals (Sweden)
Coghetto Roland
2017-07-01
Full Text Available In this article we check, with the Mizar system [2], Pascal’s theorem in the real projective plane (in projective geometry Pascal’s theorem is also known as the Hexagrammum Mysticum Theorem1. Pappus’ theorem is a special case of a degenerate conic of two lines.
Observations with a mid-plane reciprocating probe in MAST
International Nuclear Information System (INIS)
Yang, Y.; Counsell, G.F.
2003-01-01
A fast reciprocating probe has recently been installed on MAST. It has been used to measure the outboard, mid-plane scrape off layer (SOL) of L-mode plasmas, and to study the intermittent fluctuations in the SOL in L-mode and ELMy H-mode discharges. In this paper, the system and the experiments are introduced
Quantum-Well Infrared Photodetector (QWIP) Focal Plane Assembly
Jhabvala, Murzy; Jhabvala, Christine A.; Ewin, Audrey J.; Hess, Larry A.; Hartmann, Thomas M.; La, Anh T.
2012-01-01
A paper describes the Thermal Infrared Sensor (TIRS), a QWIP-based instrument intended to supplement the Operational Land Imager (OLI) for the Landsat Data Continuity Mission (LDCM). The TIRS instrument is a far-infrared imager operating in the pushbroom mode with two IR channels: 10.8 and 12 microns. The focal plane will contain three 640x512 QWIP arrays mounted on a silicon substrate. The silicon substrate is a custom-fabricated carrier board with a single layer of aluminum interconnects. The general fabrication process starts with a 4-in. (approx.10-cm) diameter silicon wafer. The wafer is oxidized, a single substrate contact is etched, and aluminum is deposited, patterned, and alloyed. This technology development is aimed at incorporating three large-format infrared detecting arrays based on GaAs QWIP technology onto a common focal plane with precision alignment of all three arrays. This focal plane must survive the rigors of flight qualification and operate at a temperature of 43 K (-230 C) for five years while orbiting the Earth. The challenges presented include ensuring thermal compatibility among all the components, designing and building a compact, somewhat modular system and ensuring alignment to very tight levels. The multi-array focal plane integrated onto a single silicon substrate is a new application of both QWIP array development and silicon wafer scale integration. The Invar-based assembly has been tested to ensure thermal reliability.
Minimum-link paths among obstacles in the plane
Mitchell, J.S.B.; Rote, G.; Woeginger, G.J.
1992-01-01
Given a set of nonintersecting polygonal obstacles in the plane, thelink distance between two pointss andt is the minimum number of edges required to form a polygonal path connectings tot that avoids all obstacles. We present an algorithm that computes the link distance (and a corresponding
A plane stress softening plasticity model for orthotropic materials
Lourenço, P.B.; Borst, R. de; Rots, J.G.
1997-01-01
A plane stress model has been developed for quasi-brittle orthotropic materials. The theory of plasticity, which is adopted to describe the inelastic behaviour, utilizes modern algorithmic concepts, including an implicit Euler backward return mapping scheme, a local Newton-Raphson method and a
Distribution of Interstellar Reddening Material in the Galactic Plane
Directory of Open Access Journals (Sweden)
Chulhee Kim
1987-12-01
Full Text Available By using the recently determined color excess and distance data of classical cepheids by Kim(1985, the distribution of interstellar reddening material was studied to see the general picture of the average rate of interstellar absorption out to about 7-8kpc in the Galactic plane in various directions from the sun.
Fixating the pelvis in the horizontal plane affects gait characteristics
Veneman, J.F.; Menger, Jasper; van Asseldonk, Edwin H.F.; van der Helm, F.C.T.; van der Kooij, Herman
2008-01-01
In assistive devices for neuro-rehabilitation, natural human motions are partly restricted by the device. This may affect the normality of walking during training. This research determines effects on gait of fixating the pelvis translations in the horizontal plane during treadmill walking. Direct
Metal-core pad-plane development for ACTAR TPC
Giovinazzo, J.; Pibernat, J.; Goigoux, T.; de Oliveira, R.; Grinyer, G. F.; Huss, C.; Mauss, B.; Pancin, J.; Pedroza, J. L.; Rebii, A.; Roger, T.; Rosier, P.; Saillant, F.; Wittwer, G.
2018-06-01
With the recent development of active targets and time projection chambers (ACTAR TPC) as detectors for fundamental nuclear physics experiments, the need arose for charge collection planes with a high density of readout channels. In order to fulfill the mechanical constraints for the ACTAR TPC device, we designed a pad-plane based on a metal-core circuit with an conceptually simple design and routing for signal readout, named FAKIR (in reference to a fakir bed of nails). A test circuit has been equipped with a micro mesh gaseous structure (micromegas) for signal amplification and a dedicated readout electronics. Test measurements have been performed with an 55Fe X-ray source giving an intrinsic energy resolution (FWHM) of 22 ± 1% at 5 . 9 keV, and with a 3-alpha source for which a resolution of about 130 ± 20 keV at 4 . 8 MeV has been estimated. The pad-plane has been mounted into a reduced size demonstrator version of the ACTAR TPC detector, in order to illustrate charged particle track reconstruction. The tests preformed with the X-ray and the 3-alpha sources shows that results obtained from pads signals are comparable to the intrinsic result from the micro-mesh signal. In addition, a simple alpha particle tracks analysis is performed to demonstrate that the pad plane allows a precise reconstruction of the direction and length of the trajectories.
Automatic test comes to focal plane array production
Skaggs, Frank L.; Barton, T. D.
1992-08-01
To meet the needs of military and commercial markets, the infrared focal plane array industry must develop new, effective and low cost methods of fabricating and testing imaging detectors. This paper describes Texas Instruments new concepts in automated testing and cold probe technology as they apply to volume production.
Plane-wave electronic structure calculations on a parallel supercomputer
International Nuclear Information System (INIS)
Nelson, J.S.; Plimpton, S.J.; Sears, M.P.
1993-01-01
The development of iterative solutions of Schrodinger's equation in a plane-wave (pw) basis over the last several years has coincided with great advances in the computational power available for performing the calculations. These dual developments have enabled many new and interesting condensed matter phenomena to be studied from a first-principles approach. The authors present a detailed description of the implementation on a parallel supercomputer (hypercube) of the first-order equation-of-motion solution to Schrodinger's equation, using plane-wave basis functions and ab initio separable pseudopotentials. By distributing the plane-waves across the processors of the hypercube many of the computations can be performed in parallel, resulting in decreases in the overall computation time relative to conventional vector supercomputers. This partitioning also provides ample memory for large Fast Fourier Transform (FFT) meshes and the storage of plane-wave coefficients for many hundreds of energy bands. The usefulness of the parallel techniques is demonstrated by benchmark timings for both the FFT's and iterations of the self-consistent solution of Schrodinger's equation for different sized Si unit cells of up to 512 atoms
On harmonicity in some Moufang-Klingenberg planes
ÇELİK, Basri; AKPINAR, Atilla; ÇİFTÇİ, Süleyman
2010-01-01
In this paper we study Moufang-Klingenberg planes M (A) defined over a local alternative ring A of dual numbers. We show that some collineations of M (A) preserve cross-ratio and thus establish a relation between harmonicity and harmonic position.
Motion on an Inclined Plane and the Nature of Science
Pendrill, Ann-Marie; Ekström, Peter; Hansson, Lena; Mars, Patrik; Ouattara, Lassana; Ryan, Ulrika
2014-01-01
Friction is an important phenomenon in everyday life. All children are familiar with playground slides, which may thus be a good starting point for investigating friction. Motion on an inclined plane is a standard physics example. This paper presents an investigation of friction by a group of 11-year olds. How did they plan their investigations?…
An Apparatus for Constructing an Electromagnetic Plane Wave Model
Kneubil, Fabiana Botelho; Loures, Marcus Vinicius Russo; Amado, William
2015-01-01
In this paper we report on an activity aimed at building an electromagnetic wave. This was part of a class on the concept of mass offered to a group of 20 pre-service Brazilian physics teachers. The activity consisted of building a plane wave using an apparatus in which it is possible to fit some rods representing electric and magnetic fields into…
The Toledo invariant, and Seshadri constants of fake projective planes
DI CERBO, Luca F.
2017-01-01
The purpose of this paper is to explicitly compute the Seshadri constants of all ample line bundles on fake projective planes. The proof relies on the theory of the Toledo invariant, and more precisely on its characterization of $\\mathbb{C}$-Fuchsian curves in complex hyperbolic spaces.
Locating an axis-parallel rectangle on a Manhattan plane
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Körner, Mark-Christoph
2014-01-01
In this paper we consider the problem of locating an axis-parallel rectangle in the plane such that the sum of distances between the rectangle and a finite point set is minimized, where the distance is measured by the Manhattan norm 1. In this way we solve an extension of the Weber problem...
Plane Wave Medical Ultrasound Imaging Using Adaptive Beamforming
DEFF Research Database (Denmark)
Holfort, Iben Kraglund; Gran, Fredrik; Jensen, Jørgen Arendt
2008-01-01
In this paper, the adaptive, minimum variance (MV) beamformer is applied to medical ultrasound imaging. The Significant resolution and contrast gain provided by the adaptive, minimum variance (MV) beamformer, introduces the possibility of plane wave (PW) ultrasound imaging. Data is obtained using...
A differentiated plane wave as an electromagnetic vortex
International Nuclear Information System (INIS)
Hannay, J H; Nye, J F
2015-01-01
Differentiating a complex scalar plane wave with respect to its direction produces an isolated straight vortex line and has a natural extension, described in earlier papers, to the vector waves of electromagnetism—a differentiated plane wave (DPW). It epitomizes destructive interference and will be shown to have the local structure of an electromagnetic vortex. In this paper its polarization structure and Poynting vector field are compared and contrasted with that of the family of linear polynomial waves, of which it is a special member. By definition this wider family has a general linear complex vector function of position multiplying a plane wave, but the function must be such that the combination satisfies Maxwell’s equations. This forces translational invariance of the function along the wavevector direction—in other words the wave is ‘non-diffracting’. In a natural sense all possible polarizations are exhibited once only. But the DPW has a distinctive polarization structure only partly explored previously. Both classes of waves share similar Poynting vector fields, which can be ‘elliptic’ (helix-like flow lines) or ‘hyperbolic’, of a repulsive nature, unexpected for a vortex. Both classes can be considered as a limit in the superposition of three closely parallel ordinary plane waves in destructive interference, and this derivation is supplied in full here. (paper)
STRUCTURAL ANALYSIS OF IN-PLANE LOADED CLT BEAMS
Directory of Open Access Journals (Sweden)
Mario Jeleč
2017-01-01
Full Text Available Cross laminated timber (CLT is a versatile engineered timber product that is increasingly well-known and of global interest in several applications such as full size plane or linear timber elements. The aim of this study involves investigating the performance of CLT beams loaded in-plane by considering bending and shear stress analysis with a special emphasis on the in-plane shear behavior including the complex internal structure of CLT. Numerical analysis based on 3D-FE models was used and compared with two existing analytical approaches, namely representative volume sub element (method I and composite beam theory (method II. The separate verification of bending and shear stresses including tree different shear failure modes was performed, and a good agreement was obtained. The main difference between the results relates to shear failure mode in the crossing areas between the orthogonally bonded lamellas in which the distribution of shear stresses τzx over the crossing areas per height of the CLT beam is not in accordance with the analytical assumptions. The presented analyses constitute the first attempt to contribute to the on-going review process of Eurocode 5 with respect to CLT beams loaded-in plane. Currently, regulations on designing these types of beams do not exist, and thus experimental and numerical investigations are planned in the future.
Fast decoding of codes from algebraic plane curves
DEFF Research Database (Denmark)
Justesen, Jørn; Larsen, Knud J.; Jensen, Helge Elbrønd
1992-01-01
Improvement to an earlier decoding algorithm for codes from algebraic geometry is presented. For codes from an arbitrary regular plane curve the authors correct up to d*/2-m2 /8+m/4-9/8 errors, where d* is the designed distance of the code and m is the degree of the curve. The complexity of finding...
Absolute parametric instability in a nonuniform plane plasma ...
Indian Academy of Sciences (India)
Abstract. The paper reports an analysis of the effect of spatial plasma nonuniformity on absolute parametric instability (API) of electrostatic waves in magnetized plane waveguides subjected to an intense high-frequency (HF) electric field using the separation method. In this case the effect of strong static magnetic field is ...
Absolute parametric instability in a nonuniform plane plasma
Indian Academy of Sciences (India)
The paper reports an analysis of the effect of spatial plasma nonuniformity on absolute parametric instability (API) of electrostatic waves in magnetized plane waveguides subjected to an intense high-frequency (HF) electric field using the separation method. In this case the effect of strong static magnetic field is considered.
Plane Symmetric Cosmological Model with Quark and Strange ...
Indian Academy of Sciences (India)
Keywords. f(R,T) theory of gravity—plane symmetric space-time—quark and strange quark matter—constant deceleration parameter. 1. Introduction. Modern astrophysical observations point out that present expansion of the Universe is an accelerated epoch. The most fascinating evidence for this is found in measurements ...
Position sensitive proportional counters as focal plane detectors
International Nuclear Information System (INIS)
Ford, J.L.C. Jr.
1979-01-01
The rise time and charge division techniques for position decoding with RC-line proportional counters are reviewed. The advantages that these detectors offer as focal plane counters for nuclear spectroscopy performed with magnetic spectrographs are discussed. The theory of operation of proportional counters as position sensing devices is summarized, as well as practical aspects affecting their application. Factors limiting the position and energy resolutions obtainable with a focal plane proportional counter are evaluated and measured position and energy loss values are presented for comparison. Detector systems capable of the multiparameter measurements required for particle identification, background suppression and ray-tracing are described in order to illustrate the wide applicability of proportional counters within complex focal plane systems. Examples of the use of these counters other than with magnetic spectrographs are given in order to demonstrate their usefulness in not only nuclear physics but also in fields such as solid state physics, biology, and medicine. The influence of the new focal plane detector systems on future magnetic spectrograph designs is discussed. (Auth.)
Integral representation in the hodograph plane of compressible flow
DEFF Research Database (Denmark)
Hansen, Erik Bent; Hsiao, G.C.
2003-01-01
Compressible flow is considered in the hodograph plane. The linearity of the equation determining the stream function is exploited to derive a representation formula involving boundary data only, and a fundamental solution to the adjoint equation. For subsonic flow, an efficient algorithm...
New bi-Hamiltonian systems on the plane
Tsiganov, A. V.
2017-06-01
We discuss several new bi-Hamiltonian integrable systems on the plane with integrals of motion of third, fourth, and sixth orders in momenta. The corresponding variables of separation, separated relations, compatible Poisson brackets, and recursion operators are also presented in the framework of the Jacobi method.
A plane-wave final-state theory of ATI
International Nuclear Information System (INIS)
Parker, J.S.; Clark, C.W.
1993-01-01
A Fermi Golden Rule calculation of ionization cross-sections provides us with the simplest example of a plane-wave final-state theory. In this method the final (unbound) state is modeled as a plane wave, an approximation that generally gives best results in the high energy limit in which the affect of the atomic potential on the final state can be neglected. A cross-section is then calculated from the matrix element connecting the bound initial state with the final state. The idea of generalizing this method to model transitions among unbound states is credited to L.V. Keldysh, and a number of related formalisms have been proposed that are consistent with the general features of experimental data. Here we describe a plane-wave final-state model of ATI that is in the spirit of these theories, but differs significantly in its implementation and predictions. We will present a comparison of the predictions of the plane-wave model with those of a full numerical integration of the time-dependent Schrodinger equation for atomic hydrogen in a radiation field. The theory and the numerical integration give good qualitative agreement in their predictions of photoelectron spectra over about 14 orders of magnitude
A bijection between phylogenetic trees and plane oriented recursive trees
Prodinger, Helmut
2017-01-01
Phylogenetic trees are binary nonplanar trees with labelled leaves, and plane oriented recursive trees are planar trees with an increasing labelling. Both families are enumerated by double factorials. A bijection is constructed, using the respective representations a 2-partitions and trapezoidal words.
Path integration on the upper half-plane
International Nuclear Information System (INIS)
Kubo, Reijiro.
1987-06-01
Feynman's path integral is considered on the Poincare upper half-plane. It is shown that the fundamental solution to the heat equation δf/δt = Δ H f can be expressed in terms of a path integral. A simple relation between the path integral and the Selberg trace formula is discussed briefly. (author)
Path Integration on the Upper Half-Plane
Reijiro, KUBO; Research Institute for Theoretical Physics Hiroshima University
1987-01-01
Feynman's path integral is considered on the Poincare upper half-plane. It is shown that the fundamental solution to the heat equation ∂f/∂t=Δ_Hf can be expressed in terms of a path integral. A simple relation between the path integral and the Selberg trace formula is discussed briefly.
A superparticle on the 'super' Poincare upper half plane
International Nuclear Information System (INIS)
Uehara, S.; Yasui, Yukinora
1988-01-01
A non-relativistic superparticle moving freely on the 'super' Poincare upper half plane is investigated. The lagrangian is invariant under the super Moebius transformations SPL (2, R), so that it can be projected into the lagrangian on the super Riemann surface. The quantum hamiltonian becomes the 'super' Laplace-Beltrami operator in the curved superspace. (orig.)
Superparticle on the 'super' Poincare upper half plane
Energy Technology Data Exchange (ETDEWEB)
Uehara, S; Yasui, Yukinora
1988-03-17
A non-relativistic superparticle moving freely on the 'super' Poincare upper half plane is investigated. The lagrangian is invariant under the super Moebius transformations SPL (2, R), so that it can be projected into the lagrangian on the super Riemann surface. The quantum hamiltonian becomes the 'super' Laplace-Beltrami operator in the curved superspace.
Intersection of Three Planes Revisited--An Algebraic Approach
Trenkler, Götz; Trenkler, Dietrich
2017-01-01
Given three planes in space, a complete characterization of their intersection is provided. Special attention is paid to the case when the intersection set does not exist of one point only. Besides the vector cross product, the tool of generalized inverse of a matrix is used extensively.
3-D Velocity Estimation for Two Planes in vivo
DEFF Research Database (Denmark)
Holbek, Simon; Pihl, Michael Johannes; Ewertsen, Caroline
2014-01-01
3-D velocity vectors can provide additional flow information applicable for diagnosing cardiovascular diseases e.g. by estimating the out-of-plane velocity component. A 3-D version of the Transverse Oscillation (TO) method has previously been used to obtain this information in a carotid flow...... and stored on the experimental scanner SARUS. The full 3-D velocity profile can be created and examined at peak-systole and end-diastole without ECG gating in two planes. Maximum out-of-plane velocities for the three peak-systoles and end-diastoles were 68.5 5.1 cm/s and 26.3 3.3 cm/s, respectively....... In the longitudinal plane, average maximum peak velocity in flow direction was 65.2 14.0 cm/s at peak-systole and 33.6 4.3 cm/s at end-diastole. A commercial BK Medical ProFocus UltraView scanner using a spectral estimator gave 79.3 cm/s and 14.6 cm/s for the same volunteer. This demonstrates that real-time 3-D...
Grace and Courtesy across the Planes of Development
Ludick, Pat
2015-01-01
Pat Ludick's commentary on grace and courtesy is established by a philosophical orientation to development: Grace is oriented to the life of the interior that is consciousness and being, and courtesy moves outward to daily living where civility reflects on success with human interactions. Pat's projected grace and courtesy across the planes is…
Processing vertical size disparities in distinct depth planes.
Duke, Philip A; Howard, Ian P
2012-08-17
A textured surface appears slanted about a vertical axis when the image in one eye is horizontally enlarged relative to the image in the other eye. The surface appears slanted in the opposite direction when the same image is vertically enlarged. Two superimposed textured surfaces with different horizontal size disparities appear as two surfaces that differ in slant. Superimposed textured surfaces with equal and opposite vertical size disparities appear as a single frontal surface. The vertical disparities are averaged. We investigated whether vertical size disparities are averaged across two superimposed textured surfaces in different depth planes or whether they induce distinct slants in the two depth planes. In Experiment 1, two superimposed textured surfaces with different vertical size disparities were presented in two depth planes defined by horizontal disparity. The surfaces induced distinct slants when the horizontal disparity was more than ±5 arcmin. Thus, vertical size disparities are not averaged over surfaces with different horizontal disparities. In Experiment 2 we confirmed that vertical size disparities are processed in surfaces away from the horopter, so the results of Experiment 1 cannot be explained by the processing of vertical size disparities in a fixated surface only. Together, these results show that vertical size disparities are processed separately in distinct depth planes. The results also suggest that vertical size disparities are not used to register slant globally by their effect on the registration of binocular direction of gaze.
Precision of Points Computed from Intersections of Lines or Planes
DEFF Research Database (Denmark)
Cederholm, Jens Peter
2004-01-01
estimates the precision of the points. When using laser scanning a similar problem appears. A laser scanner captures a 3-D point cloud, not the points of real interest. The suggested method can be used to compute three-dimensional coordinates of the intersection of three planes estimated from the point...
(AJST) A CUTTING- PLANE APPROACH FOR SEMI- INFINITE ...
African Journals Online (AJOL)
opiyo
Section 3 deals with convex semi-infinite programming while in section 4 we give some hints for dealing with the geometric case. The paper ends with concluding remarks along with a comparison of the cutting-plane philosophy with other existing approaches and a claim for implementing. Decision Support System for this ...
A cutting- plane approach for semi- infinite mathematical programming
African Journals Online (AJOL)
Many situations ranging from industrial to social via economic and environmental problems may be cast into a Semi-infinite mathematical program. In this paper, the cutting-plane approach which lends itself better for standard non-linear programs is exploited with good reasons for grappling with linear, convex and ...
Facial rejuvenation with fillers: The dual plane technique
Directory of Open Access Journals (Sweden)
Giovanni Salti
2015-01-01
Full Text Available Background: Facial aging is characterized by skin changes, sagging and volume loss. Volume is frequently addressed with reabsorbable fillers like hyaluronic acid gels. Materials and Methods: From an anatomical point of view, the deep and superficial fat compartments evolve differently with aging in a rather predictable manner. Volume can therefore be restored following a technique based on restoring first the deep volumes and there after the superficial volumes. We called this strategy "dual plane". A series of 147 consecutive patients have been treated with fillers using the dual plane technique in the last five years. Results: An average of 4.25 session per patient has been carried out for a total of 625 treatment sessions. The average total amount of products used has been 12 ml per patient with an average amount per session of 3.75 ml. We had few and limited adverse events with this technique. Conclusion: The dual plane technique is an injection technique based on anatomical logics. Different types of products can be used according to the plane of injection and their rheology in order to obtain a natural result and few side effects.
Occlusal plane rotation: aesthetic enhancement in mandibular micrognathia.
Rosen, H M
1993-06-01
Patients afflicted with extreme degrees of mandibular micrognathia typically have vertically deficient rami as well as sagittally deficient mandibular bodies. This results in deficient posterior facial height, an obtuse gonial angle, excessively steep occlusal and mandibular planes, and a compensatory increase in anterior facial height. The entire maxillomandibular complex is overrotated in a clockwise direction. Standard orthognathic surgical correction fails to address this rotational deformity. As a consequence, the achieved projection of the lower face is inadequate, posterior facial height is further reduced, and occlusal and mandibular planes remain steep. Eleven patients with severe mandibular micrognathia underwent a surgical correction involving occlusal plane rotation to its normal orientation relative to Frankfort horizontal. This was accomplished by Le Fort I osteotomy to shorten the anterior maxilla (creating open bites in seven patients and making preexisting open bites worse in four patients) and sagittal split ramus osteotomies to advance and rotate the mandibular body counterclockwise, thus closing the surgically produced open bite. Counterclockwise rotation of the mandible afforded significantly greater sagittal displacement at the B point (mean 17 mm) than at the first molar (mean 10 mm) and produced adequate degrees of projection of the lower face when accompanied by a modest sliding genioplasty (mean 6.9 mm). Total advancement at the pogonion was a mean of 25.2 mm. In addition, posterior facial height was preserved, and mandibular and occlusal planes were normalized to mean angles of 27 and 10 degrees, respectively. At follow-up, which ranged from 9 to 24 months with a mean of 14.1 months, the mean sagittal relapse at the B point was 1.9 mm. Although heretofore considered unstable and therefore not clinically accepted, maxillomandibular counterclockwise rotation to normalize the occlusal plane rotational deformity provides stable, aesthetically
The plane strain tests in the PROMETRA program
International Nuclear Information System (INIS)
Cazalis, B.; Desquines, J.; Carassou, S.; Le Jolu, T.; Bernaudat, C.
2016-01-01
A fuel cladding mechanical test, performed under conditions of plane strain deformation in the transverse direction of tube axis, was originally developed at Pennsylvania State University. It was decided to implement this original test within the PROMETRA program using the same experimental procedure and its optimization for a ring mechanical testing on plane strain conditions (PST tests) in hot cells laboratory. This paper presents a detailed description and an interpretation of the Plane Strain Tensile (PST) tests performed in the framework of the PROMETRA program on fresh and irradiated claddings. At first, the context of the PST tests is situated and the specificities of these tests implemented at CEA are justified. Indeed, a significant adjustment of the original experimental procedure is carried out in order to test the irradiated fuel cladding in the best possible conditions. Then, the tests results on fresh Zircaloy-4 and on irradiated Zircaloy-4, M5™ and ZIRLO ® specimens are gathered. The main analyses in support of these tests, such as metallographies, fractographic examinations and finite element simulations are detailed. Finally, a synthesis of the interpretation of the tests is proposed. The PST test seems only representative of plane strain fracture conditions when the test material is very ductile (fresh or high temperature or low hydride material like M5TM). However, it provides a relevant representation of the RIA rupture initiation which is observed in irradiated cladding resulting from hydride rim damage due to the strong irradiation of a fuel rod. - Highlights: • A plane strain mechanical test performed on fuel rod claddings is described. • The tests are performed in the framework of the French PROMETRA program. • Fresh Zircaloy-4 and irradiated Zircaloy-4, M5 and ZIRLO specimens are tested. • The main analyses in support of these tests are detailed. • A synthesis of the interpretation of the PST tests is proposed.
The plane strain tests in the PROMETRA program
Energy Technology Data Exchange (ETDEWEB)
Cazalis, B., E-mail: bernard.cazalis@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire, IRSN/PSN-RES, F-13115 Saint-Paul Lez Durance BP3 (France); Desquines, J. [Institut de Radioprotection et de Sûreté Nucléaire, IRSN/PSN-RES, F-13115 Saint-Paul Lez Durance BP3 (France); Carassou, S.; Le Jolu, T. [Commissariat à l' Energie Atomique, CEA/DEN/DMN, F- 91191 Gif-sur-Yvette (France); Bernaudat, C. [Electricité de France, EDF/SEPTEN, F-69628 Villeurbanne (France)
2016-04-15
A fuel cladding mechanical test, performed under conditions of plane strain deformation in the transverse direction of tube axis, was originally developed at Pennsylvania State University. It was decided to implement this original test within the PROMETRA program using the same experimental procedure and its optimization for a ring mechanical testing on plane strain conditions (PST tests) in hot cells laboratory. This paper presents a detailed description and an interpretation of the Plane Strain Tensile (PST) tests performed in the framework of the PROMETRA program on fresh and irradiated claddings. At first, the context of the PST tests is situated and the specificities of these tests implemented at CEA are justified. Indeed, a significant adjustment of the original experimental procedure is carried out in order to test the irradiated fuel cladding in the best possible conditions. Then, the tests results on fresh Zircaloy-4 and on irradiated Zircaloy-4, M5™ and ZIRLO{sup ®} specimens are gathered. The main analyses in support of these tests, such as metallographies, fractographic examinations and finite element simulations are detailed. Finally, a synthesis of the interpretation of the tests is proposed. The PST test seems only representative of plane strain fracture conditions when the test material is very ductile (fresh or high temperature or low hydride material like M5TM). However, it provides a relevant representation of the RIA rupture initiation which is observed in irradiated cladding resulting from hydride rim damage due to the strong irradiation of a fuel rod. - Highlights: • A plane strain mechanical test performed on fuel rod claddings is described. • The tests are performed in the framework of the French PROMETRA program. • Fresh Zircaloy-4 and irradiated Zircaloy-4, M5 and ZIRLO specimens are tested. • The main analyses in support of these tests are detailed. • A synthesis of the interpretation of the PST tests is proposed.
Positioning of electrode plane systematically influences EIT imaging
International Nuclear Information System (INIS)
Krueger-Ziolek, Sabine; Schullcke, Benjamin; Kretschmer, Jörn; Möller, Knut; Zhao, Zhanqi; Müller-Lisse, Ullrich
2015-01-01
Up to now, the impact of electrode positioning on electrical impedance tomography (EIT) had not been systematically analyzed due to the lack of a reference method. The aim of the study was to determine the impact of electrode positioning on EIT imaging in spontaneously breathing subjects at different ventilation levels with our novel lung function measurement setup combining EIT and body plethysmography. EIT measurements were conducted in three transverse planes between the 3rd and 4th intercostal space (ICS), at the 5th ICS and between the 6th and 7th ICS (named as cranial, middle and caudal) on 12 healthy subjects. Pulmonary function tests were performed simultaneously by body plethysmography to determine functional residual capacity (FRC), vital capacity (VC), tidal volume (VT), expiratory reserve volume (ERV), and inspiratory reserve volume (IRV). Ratios of impedance changes and body plethysmographic volumes were calculated for every thorax plane (ΔI_E_R_V/ERV, ΔI_V_T/VT and ΔI_I_R_V/IRV). In all measurements of a subject, FRC values and VC values differed ≤5%, which confirmed that subjects were breathing at comparable end-expiratory levels and with similar efforts. In the cranial thorax plane the normalized ΔI_E_R_V/ERV ratio in all subjects was significantly higher than the normalized ΔI_I_R_V/IRV ratio whereas the opposite was found in the caudal chest plane. No significant difference between the two normalized ratios was found in the middle thoracic plane. Depending on electrode positioning, impedance to volume ratios may either increase or decrease in the same lung condition, which may lead to opposite clinical decisions. (paper)
Positioning of electrode plane systematically influences EIT imaging.
Krueger-Ziolek, Sabine; Schullcke, Benjamin; Kretschmer, Jörn; Müller-Lisse, Ullrich; Möller, Knut; Zhao, Zhanqi
2015-06-01
Up to now, the impact of electrode positioning on electrical impedance tomography (EIT) had not been systematically analyzed due to the lack of a reference method. The aim of the study was to determine the impact of electrode positioning on EIT imaging in spontaneously breathing subjects at different ventilation levels with our novel lung function measurement setup combining EIT and body plethysmography. EIT measurements were conducted in three transverse planes between the 3rd and 4th intercostal space (ICS), at the 5th ICS and between the 6th and 7th ICS (named as cranial, middle and caudal) on 12 healthy subjects. Pulmonary function tests were performed simultaneously by body plethysmography to determine functional residual capacity (FRC), vital capacity (VC), tidal volume (VT), expiratory reserve volume (ERV), and inspiratory reserve volume (IRV). Ratios of impedance changes and body plethysmographic volumes were calculated for every thorax plane (ΔIERV/ERV, ΔIVT/VT and ΔIIRV/IRV). In all measurements of a subject, FRC values and VC values differed ≤5%, which confirmed that subjects were breathing at comparable end-expiratory levels and with similar efforts. In the cranial thorax plane the normalized ΔIERV/ERV ratio in all subjects was significantly higher than the normalized ΔIIRV/IRV ratio whereas the opposite was found in the caudal chest plane. No significant difference between the two normalized ratios was found in the middle thoracic plane. Depending on electrode positioning, impedance to volume ratios may either increase or decrease in the same lung condition, which may lead to opposite clinical decisions.
Orientifold Planes, Type I Wilson Lines and Non-BPS D-branes
International Nuclear Information System (INIS)
Hyakutake, Y.; Imamura, Y.; Sugimoto, S.
2000-01-01
There is a longstanding puzzle concerned with the existence of Op-planes with p≥6, which are orientifold p-planes of negative charge with stuck Dp-branes. We study the consistency of configurations with various orientifold planes and propose a resolution to this puzzle. It is argued that O6-planes are possible in massive IIA theory with odd cosmological constant, while O7-planes and O8-planes are not allowed. Various relations between orientifold planes and non-BPS D-branes are also addressed. (author)
Orientifold Planes, Type I Wilson Lines and Non-BPS D-branes
Hyakutake, Yoshifumi; Imamura, Yosuke; Sugimoto, Shigeki
2000-01-01
There is a longstanding puzzle concerned with the existence of Op~-planes with p>=6, which are orientifold p-planes of negative charge with stuck Dp-branes. We study the consistency of configurations with various orientifold planes and propose a resolution to this puzzle. It is argued that O6~-planes are possible in massive IIA theory with odd cosmological constant, while O7~-planes and O8~-planes are not allowed. Various relations between orientifold planes and non-BPS D-branes are also addr...
Frazin, Richard A
2016-04-01
A new generation of telescopes with mirror diameters of 20 m or more, called extremely large telescopes (ELTs), has the potential to provide unprecedented imaging and spectroscopy of exoplanetary systems, if the difficulties in achieving the extremely high dynamic range required to differentiate the planetary signal from the star can be overcome to a sufficient degree. Fully utilizing the potential of ELTs for exoplanet imaging will likely require simultaneous and self-consistent determination of both the planetary image and the unknown aberrations in multiple planes of the optical system, using statistical inference based on the wavefront sensor and science camera data streams. This approach promises to overcome the most important systematic errors inherent in the various schemes based on differential imaging, such as angular differential imaging and spectral differential imaging. This paper is the first in a series on this subject, in which a formalism is established for the exoplanet imaging problem, setting the stage for the statistical inference methods to follow in the future. Every effort has been made to be rigorous and complete, so that validity of approximations to be made later can be assessed. Here, the polarimetric image is expressed in terms of aberrations in the various planes of a polarizing telescope with an adaptive optics system. Further, it is shown that current methods that utilize focal plane sensing to correct the speckle field, e.g., electric field conjugation, rely on the tacit assumption that aberrations on multiple optical surfaces can be represented as aberration on a single optical surface, ultimately limiting their potential effectiveness for ground-based astronomy.
Robust micromachining of compliant mechanisms for out-of-plane microsensors
Khosraviani, Kourosh
2013-01-01
Micro-Electro-Mechanical-Systems (MEMS) take advantage of a wide range of very reliable, and well established existing microelectronics fabrication techniques. Due to the planar nature of these techniques, out-of-plane MEMS devices must be fabricated in-plane and assembled afterwards in order to create out-of-plane three-dimensional structures. Out-of-plane microstructures extend the design space of the MEMS based devices and overcome many limitations of the in-plane processing. Nevertheless,...
Tambake, Deepti; Shetty, Shilpa; Satish Babu, C L; Fulari, Sangamesh G
2014-12-01
The study was undertaken to evaluate the parallelism between hamular-incisive-papilla plane (HIP) and the Campers plane. And to determine which part of the posterior reference of the tragus i.e., the superior, middle or the inferior of the Camper's plane is parallel to HIP using digital lateral cephalograms. Fifty edentulous subjects with well formed ridges were selected for the study. The master casts were obtained using the standard selective pressure impression procedure. On the deepest point of the hamular notches and the centre of the incisive papilla stainless steel spherical bearings were glued to the cast at the marked points. The study templates were fabricated with autopolymerizing acrylic resin. The subjects were prepared for the lateral cephalograms. Stainless steel spherical bearings were adhered to the superior, middle, inferior points of the tragus of the ear and inferior border of the ala of the nose using surgical adhesive tape. The subjects with study templates were subjected to lateral cephalograms. Cephalometric tracings were done using Autocad 2010 software. Lines were drawn connecting the incisive papilla and hamular notch and the stainless steel spherical bearings placed on the superior, middle and inferior points on the tragus and the ala of the nose i.e., the Campers line S, Campers line M, Campers line I. The angles between the three Camper's line and the HIP were measured and recorded. Higher mean angulation was recorded in Campers line S -HIP (8.03) followed by Campers line M-HIP (4.60). Campers line I-HIP recorded the least angulation (3.80). The HIP is parallel to the Camper's plane. The Camper's plane formed with the posterior reference point as inferior point of the tragus is relatively parallel to the HIP.
METHOD FOR DETERMINATION OF FOCAL PLANE LOCATION OF FOCUSING COMPONENTS
Directory of Open Access Journals (Sweden)
A. I. Ivashko
2017-01-01
Full Text Available Mass-production of different laser systems often requires utilization of the focal spot size method for determination of output laser beam spatial characteristics. The main challenge of this method is high accuracy maintenance of a CCD camera beam profiler in the collecting lens focal plane. The aim of our work is development of new method for placing of photodetector array in the collecting lens focal plane with high accuracy.Proposed technique is based on focusing of several parallel laser beams. Determination of the focal plane position requires only longitudinal translation of the CCD-camera to find a point of laser beams intersection. Continuous-wave (CW diode-pumped laser emitting in the spectral region near 1μm was created to satisfy the requirements of the developed technique. Designed microchip laser generates two stigmatic Gaussian beams with automatically parallel beam axes due to independent pumping of different areas of the one microchip crystal having the same cavity mirrors.It was theoretically demonstrated that developed method provides possibility of the lenses focal plane determination with 1 % accuracy. The microchip laser generates two parallel Gaussian beams with divergence of about 10 mrad. Laser output power can be varied in the range of 0.1–1.5 W by changing the pumping laser diode electrical current. The distance between two beam axes can be changed in the range of 0.5–5.0 mm.We have proposed method for determination of positive lens focal plane location by using of CCDcamera and two laser beams with parallel axes without utilization of additional optical devices. We have developed CW longitudinally diode pumped microchip laser emitting in the 1-μm spectral region that can be used in the measuring instrument that doesn’t require precision mechanical components for determination of focal plane location with 1 % accuracy. The overall dimensions of laser head was 70 × 40 × 40 mm3 and maximum power consumption was
Roof planes detection via a second-order variational model
Benciolini, Battista; Ruggiero, Valeria; Vitti, Alfonso; Zanetti, Massimo
2018-04-01
The paper describes a unified automatic procedure for the detection of roof planes in gridded height data. The procedure exploits the Blake-Zisserman (BZ) model for segmentation in both 2D and 1D, and aims to detect, to model and to label roof planes. The BZ model relies on the minimization of a functional that depends on first- and second-order derivatives, free discontinuities and free gradient discontinuities. During the minimization, the relative strength of each competitor is controlled by a set of weight parameters. By finding the minimum of the approximated BZ functional, one obtains: (1) an approximation of the data that is smoothed solely within regions of homogeneous gradient, and (2) an explicit detection of the discontinuities and gradient discontinuities of the approximation. Firstly, input data is segmented using the 2D BZ. The maps of data and gradient discontinuities are used to isolate building candidates and planar patches (i.e. regions with homogeneous gradient) that correspond to roof planes. Connected regions that can not be considered as buildings are filtered according to both patch dimension and distribution of the directions of the normals to the boundary. The 1D BZ model is applied to the curvilinear coordinates of boundary points of building candidates in order to reduce the effect of data granularity when the normals are evaluated. In particular, corners are preserved and can be detected by means of gradient discontinuity. Lastly, a total least squares model is applied to estimate the parameters of the plane that best fits the points of each planar patch (orthogonal regression with planar model). Refinement of planar patches is performed by assigning those points that are close to the boundaries to the planar patch for which a given proximity measure assumes the smallest value. The proximity measure is defined to account for the variance of a fitting plane and a weighted distance of a point from the plane. The effectiveness of the
Aquantis C-Plane Ocean Current Turbine Project
Energy Technology Data Exchange (ETDEWEB)
Fleming, Alex [Dehlsen Associates, LLC, Santa Barbara, CA (United States)
2015-09-16
The Aquantis 2.5 MW Ocean Current Generation Device technology developed by Dehlsen Associates, LLC (DA) is a derivation of wind power generating technology (a means of harnessing a slow moving fluid) adapted to the ocean environment. The Aquantis Project provides an opportunity for accelerated technological development and early commercialization, since it involves the joining of two mature disciplines: ocean engineering and wind turbine design. The Aquantis Current Plane (C-Plane) technology is an ocean current turbine designed to extract kinetic energy from a current flow. The technology is capable of achieving competitively priced, continuous, base-load, and reliable power generation from a source of renewable energy not before possible in this scale or form.
Uncooled infrared focal plane array imaging in China
Lei, Shuyu
2015-06-01
This article reviews the development of uncooled infrared focal plane array (UIFPA) imaging in China in the past decade. Sensors based on optical or electrical read-out mechanism were developed but the latter dominates the market. In resistive bolometers, VOx and amorphous silicon are still the two major thermal-sensing materials. The specifications of the IRFPA made by different manufactures were collected and compared. Currently more than five Chinese companies and institutions design and fabricate uncooled infrared focal plane array. Some devices have sensitivity as high as 30 mK; the largest array for commercial products is 640×512 and the smallest pixel size is 17 μm. Emphasis is given on the pixel MEMS design, ROIC design, fabrication, and packaging of the IRFPA manufactured by GWIC, especially on design for high sensitivities, low noise, better uniformity and linearity, better stabilization for whole working temperature range, full-digital design, etc.
Segmented focal plane detector for light and heavy ions
International Nuclear Information System (INIS)
Wolfs, F.L.H.; Bryan, D.C.; Kurz, K.L.; Herrick, D.M.; Perera, P.A.A.; White, C.A.
1992-01-01
A segmented focal plane detector for an Enge split-pole spectrograph has been developed for the study of breakup reactions at very low relative energies. It consists of a 61 cm long segmented position-sensitive parallel plate avalanche counter backed by a large Bragg curve detector. A segmented plastic scintillator is mounted behind the anode of the Bragg curve detector and is used for particle identification of low-ionizing particles. The dead space between the two sections of the focal plane detector is 2.5 mm. The intrinsic position resolution of the detector is 1 mm. The intrinsic energy resolution depends on the energy of the incident ion and can be as good as 0.55%. The nuclear charge and mass resolutions are 0.3 e and 0.3 u, respectively. (orig.)
Target plane imaging system for the Nova laser
International Nuclear Information System (INIS)
Swift, C.D.; Bliss, E.S.; Jones, W.A.; Reeves, R.J.; Seppala, L.G.; Shelton, R.T.; VanArsdall, P.J.
1985-01-01
The Nova laser, in operation since December 1984, is capable of irradiating targets with light at 1.05 μm, 0.53 μm, and 0.35 μm. Correct alignment of these harmonic beams uses a system called a target plane imager (TPI). It is a large microscope (four meters long, weighing one thousand kilograms) that relays images from the target chamber center to a video optics module located on the outside of the chamber. Several modes of operation are possible including: near-field viewing and far-field viewing at three magnifications and three wavelengths. In addition, the entire instrument can be scanned in X,Y,Z to examine various planes near chamber center. Performance of this system and its computer controls will be described
Metallization of high aspect ratio, out of plane structures
DEFF Research Database (Denmark)
Vazquez, Patricia; Dimaki, Maria; Svendsen, Winnie Edith
2009-01-01
This work is dedicated to developing a novel three dimensional structure for electrochemical measurements in neuronal studies. The final prototype will allow not only for the study and culture on chip of neuronal cells, but also of brain tissue. The use of out-of-plane electrodes instead of planar...... ones increases the sensitivity of the system and increases the signal-to-noise ratio in the recorded signals, due to the higher availability of surface area. The main bottleneck of the out-of-plane electrode fabrication lies in the metallization process for transforming them into active electrodes......, since the coverage of the side walls of almost vertical pillars is not trivial by standard processes in a clean room facility. This paper will discuss the different steps taken towards this goal and present the results that we have obtained so far....
Eight plane IPND [Integration Prototype Near Detector] mechanical testing
International Nuclear Information System (INIS)
Zhao, A.; Guarino, V.; Wood, K.; Nephew, T.; Ayres, D.
2008-01-01
A mechanical test of an 8 plane IPND mechanical prototype, which was constructed using extrusions from the testing/tryout of the 16 cell prototype extrusion die in Argonne National Laboratory, was conducted. There were 4 vertical and 4 horizontal planes in this 8 plane IPND prototype. Each vertical plane had four 16 cell extrusions, while each horizontal plane had six 16 cell extrusions. Each plane was glued together using the formulation of Devcon adhesive, Devcon 60. The vertical extrusions used in the vertical planes shares the same dimensions as the horizontal extrusions in the horizontal planes with the average web thickness of 2.1 mm and the average wall thickness of 3.1 mm. This mechanical prototype was constructed with end-seals on the both ends of the vertical extrusions. The gaps were filled with epoxy between extrusions and end-seals. The overall dimension of IPND is 154.8 by 103.1 by 21.7 inches with the weight of approximately 1200 kg, as shown in a figure. Two similar mechanical tests of 3 layer and 11 layer prototypes have been done in order to evaluate the strength of the adhesive joint between extrusions in the NOvA detector. The test showed that the IPND prototype was able to sustain under the loading of weight of itself and scintillator. Two FEA models were built to verify the measurement data from the test. The prediction from FEA slice model seems correlated reasonably well to the test result, even under a 'rough' estimated condition for the wall thickness (from an untuned die) and an unknown property of 'garage type' extrusion. A full size of FEA 3-D model also agrees very well with the test data from strain gage readings. It is worthy to point out that the stress distribution of the structure is predominantly determined by the internal pressure, while the buckling stability relies more on the loading weight from the extrusions themselves and scintillate. Results of conducted internal pressure tests, including 3- cell, 11-cell and the IPND
Scanned Image Projection System Employing Intermediate Image Plane
DeJong, Christian Dean (Inventor); Hudman, Joshua M. (Inventor)
2014-01-01
In imaging system, a spatial light modulator is configured to produce images by scanning a plurality light beams. A first optical element is configured to cause the plurality of light beams to converge along an optical path defined between the first optical element and the spatial light modulator. A second optical element is disposed between the spatial light modulator and a waveguide. The first optical element and the spatial light modulator are arranged such that an image plane is created between the spatial light modulator and the second optical element. The second optical element is configured to collect the diverging light from the image plane and collimate it. The second optical element then delivers the collimated light to a pupil at an input of the waveguide.
The retroperitoneal interfascial planes: current overview and future perspectives.
Ishikawa, Kazuo; Nakao, Shota; Nakamuro, Makoto; Huang, Tai-Ping; Nakano, Hiroshi
2016-07-01
Recently, the concept of interfascial planes has become the prevalent theory among radiologists for understanding the retroperitoneal anatomy, having replaced the classic tricompartmental theory. However, it is a little known fact that the concept remains incomplete and includes embryological errors, which have been revised on the basis of our microscopic study. We believe that the concept not only provides a much clearer understanding of the retroperitoneal anatomy, but it also allows further development for diagnosis and treatment of retroperitoneal injuries and diseases, should it become an accomplished theory. We explain the history and outline of the concept of interfascial planes, correct common misunderstandings about the concept, explain the unconsciously applied therapeutic procedures based on the concept, and present future perspectives of the concept using our published and unpublished data. This knowledge could be essential to acute care physicians and surgeons sometime soon.
Parallel Multi-Focusing Using Plane Wave Decomposition
DEFF Research Database (Denmark)
Misaridis, Thanassis; Munk, Peter; Jensen, Jørgen Arendt
2003-01-01
of desired 2-D sensitivity functions is specified, for multi-focusing in a number of directions. The field along these directions is decomposed to a sufficiently large (for accurate specification) number of plane waves, which are then back-propagated to all transducer elements. The contributions of all plane...... waves result in one time function per element. The numerical solution is presented and discussed. It contains pulses with a variation in central frequency and time-varying apodization across the aperture (dynamic apodization). The RMS difference between the transmitted field using the calculated pulse...... of the transmitted pulses is based on the directivity spectrum method, a generalization of the angular spectrum method, a generalization of the angular spectrum method, containing no evanescent waves. The underlying theory is based on the Fourier slice theorem, and field reconstruction from projections. First a set...
Soft modes in the easy plane pyrochlore antiferromagnet
International Nuclear Information System (INIS)
Champion, J D M; Holdsworth, P C W
2004-01-01
Thermal fluctuations lift the high ground state degeneracy of the classical nearest neighbour pyrochlore antiferromagnet, with easy plane anisotropy, giving a first-order phase transition to a long range ordered state. We show, from spin wave analysis and numerical simulation, that even below this transition a continuous manifold of states, of dimension N 2/3 , exist (N is the number of degrees of freedom). As the temperature goes to zero a further 'order by disorder' selection is made from this manifold. The pyrochlore antiferromagnet Er 2 Ti 2 O 7 is believed to have an easy plane anisotropy and is reported to have the same magnetic structure. This is perhaps surprising, given that the dipole interaction lifts the degeneracy of the classical model in favour of a different structure. We interpret our results in the light of these facts
Quantum scattering beyond the plane-wave approximation
Karlovets, Dmitry
2017-12-01
While a plane-wave approximation in high-energy physics works well in a majority of practical cases, it becomes inapplicable for scattering of the vortex particles carrying orbital angular momentum, of Airy beams, of the so-called Schrödinger cat states, and their generalizations. Such quantum states of photons, electrons and neutrons have been generated experimentally in recent years, opening up new perspectives in quantum optics, electron microscopy, particle physics, and so forth. Here we discuss the non-plane-wave effects in scattering brought about by the novel quantum numbers of these wave packets. For the well-focused electrons of intermediate energies, already available at electron microscopes, the corresponding contribution can surpass that of the radiative corrections. Moreover, collisions of the cat-like superpositions of such focused beams with atoms allow one to probe effects of the quantum interference, which have never played any role in particle scattering.
Cutting Planes for Branch-and-Price Algorithms
DEFF Research Database (Denmark)
Desaulniers, Guy; Desrosiers, Jacques; Spoorendonk, Simon
2011-01-01
This article presents a general framework for formulating cutting planes in the context of column generation for integer programs. Valid inequalities can be derived using the variables of an equivalent compact formulation (i.e., the subproblem variables) or the master problem variables. In the fi......This article presents a general framework for formulating cutting planes in the context of column generation for integer programs. Valid inequalities can be derived using the variables of an equivalent compact formulation (i.e., the subproblem variables) or the master problem variables....... In the first case, cuts are added to the compact formulation, either at the master level or the subproblem level, and the decomposition process is reapplied. In the second case, we show that it is possible to model inequalities defined on the master problem variables by adding new variables and constraints......, and the cutting stock problem. © 2011 Wiley Periodicals, Inc. NETWORKS, Vol. 58(4), 301–310 2011...
Probing VCMA in MTJs with in-plane magnetization
Directory of Open Access Journals (Sweden)
M. Williamson
2017-11-01
Full Text Available Voltage controlled magnetic anisotropy (VCMA is a novel method to switch magnetizations in low-power and ultra-fast applications based on magnetic tunnel junctions (MTJs. Here we explore the ferromagnetic resonance (FMR technique to probe VCMA in situations where other methods cannot be applied. We quantify VCMA in CoFeB/MgO/CoFeB MTJ nanopillars with in-plane magnetizations where our FMR method is unique in providing direct information about VCMA. We observe a quadratic shift of the FMR resonance field when a voltage bias is applied across the MTJ. The VCMA energy corresponding to the quadratic shift varies with an energy factor of 8.2μJ/m2 for 1 V2/nm2. These results are important for understanding magnetodynamics in MTJ-based applications with in-plane magnetizations.
Neutrino fluxes from the Galactic plane and the ANTARES limit
Directory of Open Access Journals (Sweden)
Fusco Luigi Antonio
2016-01-01
Full Text Available The existence of cosmic neutrinos has been reported by the IceCube Collaboration. Though this measurement is consistent with an isotropic neutrino flux, a sub-dominant galactic component coming from extended regions such as the Galactic Plane cannot be excluded. The ANTARES detector, located in the Mediterranean Sea, is currently the largest and longest operated under-water neutrino telescope; its effective area and good exposure to the Southern Sky allow to constrain an enhanced muon neutrino emission from extended sources such as the Galactic Plane. ANTARES data from 2007 to 2013 have been analysed and upper limits on the neutrino production from the central region of our galaxy have been set.
Pittschieler, Elisabeth; Foltin, Andrea; Falkensammer, Frank; Figl, Michael; Birkfellner, Wolfgang; Jonke, Erwin; Bantleon, Hans-Peter
2016-01-01
The aim of this study was to investigate the hamulus-incisive-papilla (HIP) plane as an alternative for transferring the three-dimensional position of a patient's maxilla to an articulator. Camper, Frankfurt horizontal, occlusal, and HIP planes were evaluated in 21 patients' computed tomography scans and compared to one another. Analysis of variance showed significant differences between all planes, with the HIP plane being closest to the occlusal plane (HIP-OP: 0.6 ± 4.0 degrees). Frankfurt and Camper planes, being more peripheral, showed higher geometric asymmetries. The HIP plane, when used for articulator mounting, results in a closer and more technically reliable patient relationship in a clinical and laboratory context.
Coupling of lipid membrane elasticity and in-plane dynamics
Tsang, Kuan-Yu; Lai, Yei-Chen; Chiang, Yun-Wei; Chen, Yi-Fan
2017-07-01
Biomembranes exhibit liquid and solid features concomitantly with their in-plane fluidity and elasticity tightly regulated by cells. Here, we present experimental evidence supporting the existence of the dynamics-elasticity correlations for lipid membranes and propose a mechanism involving molecular packing densities to explain them. This paper thereby unifies, at the molecular level, the aspects of the continuum mechanics long used to model the two membrane features. This ultimately may elucidate the universal physical principles governing the cellular phenomena involving biomembranes.
Bounds on poloidal kinetic energy in plane layer convection
Tilgner, A.
2017-12-01
A numerical method is presented that conveniently computes upper bounds on heat transport and poloidal energy in plane layer convection for infinite and finite Prandtl numbers. The bounds obtained for the heat transport coincide with earlier results. These bounds imply upper bounds for the poloidal energy, which follow directly from the definitions of dissipation and energy. The same constraints used for computing upper bounds on the heat transport lead to improved bounds for the poloidal energy.
Semiclassical and quantum motions on the non-commutative plane
International Nuclear Information System (INIS)
Baldiotti, M.C.; Gazeau, J.P.; Gitman, D.M.
2009-01-01
We study the canonical and the coherent state quantizations of a particle moving in a magnetic field on the non-commutative plane. Using a θ-modified action, we perform the canonical quantization and analyze the gauge dependence of the theory. We compare coherent states quantizations obtained through Malkin-Man'ko states and circular squeezed states. The relation between these states and the 'classical' trajectories is investigated, and we present numerical explorations of some semiclassical quantities.
Semiclassical and quantum motions on the non-commutative plane
Energy Technology Data Exchange (ETDEWEB)
Baldiotti, M.C., E-mail: baldiott@fma.if.usp.b [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318-CEP, 05315-970 Sao Paulo, S.P. (Brazil); Gazeau, J.P., E-mail: gazeau@apc.univ-paris7.f [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318-CEP, 05315-970 Sao Paulo, S.P. (Brazil); Gitman, D.M., E-mail: gitman@dfn.if.usp.b [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318-CEP, 05315-970 Sao Paulo, S.P. (Brazil)
2009-10-19
We study the canonical and the coherent state quantizations of a particle moving in a magnetic field on the non-commutative plane. Using a theta-modified action, we perform the canonical quantization and analyze the gauge dependence of the theory. We compare coherent states quantizations obtained through Malkin-Man'ko states and circular squeezed states. The relation between these states and the 'classical' trajectories is investigated, and we present numerical explorations of some semiclassical quantities.
An N=8 superconformal particle in the half-plane
Energy Technology Data Exchange (ETDEWEB)
Lechtenfeld, Olaf, E-mail: lechtenf@itp.uni-hannover.d [Leibniz Universitaet, Hannover (Germany). Inst. fuer Theoretische Physik; Toppan, Francesco, E-mail: toppan@cbpf.b [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)
2011-07-01
By imposing global supersymmetry and scale invariance we construct an N=8 superconformal mechanical system based on the inhomogeneous (2,8,6) linear multiplet. The unique action describes a special Kahler sigma model with a Calogero-type potential and Fayet-Iliopoulos terms. The classical dynamics of the two propagating bosons is restricted to a (warped) half-plane and bounded. We numerically inspect typical trajectories of this special particle. (author)
A focal plane detector for both light and heavy ions
International Nuclear Information System (INIS)
Ophel, T.R.; Johnston, A.
1978-05-01
The characteristics of a multi-element, ionization-type focal plane detector with an effective length of 53 cm have been evaluated for various ions ranging between protons and 32 S. The position resolution obtained is typically 1 mm. Excellent energy (0.49% for 16 O) and angular resolution (0.2 degrees with respect to beam direction for 7 Li) have been obtained enabling clean separation of ion species at essentially full angular acceptance of a split-pole spectrograph
On semantic cutting planes with very small coefficients
Czech Academy of Sciences Publication Activity Database
Lauria, M.; Thapen, Neil
2018-01-01
Roč. 136, August (2018), s. 70-75 ISSN 0020-0190 R&D Projects: GA ČR GBP202/12/G061 Institutional support: RVO:67985840 Keywords : theory of computation * proof complexity * cutting planes Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.748, year: 2016 https://www.sciencedirect.com/science/article/pii/S0020019018300875
Fatigue Crack Propagation Simulation in Plane Stress Constraint
DEFF Research Database (Denmark)
Ricardo, Luiz Carlos Hernandes; Spinelli, Dirceu
2010-01-01
Nowadays, structural and materials engineers develop structures and materials properties using finite element method. This work presents a numerical determination of fatigue crack opening and closure stress intensity factors of a C(T) specimen. Two different standard variable spectrum loadings...... are utilized, Mini-Falstaff and Wisper. The effects in two-dimensional (2D) small scale yielding models of fatigue crack growth were studied considering plane stress constraint....
Equilibrium states for a plane incompressible perfect fluid
Energy Technology Data Exchange (ETDEWEB)
Boldrighini, C; Frigio, S [Camerino Univ. (Italy). Istituto di Matematica
1980-01-01
We associate to the plane incompressible Euler equation with periodic conditions the corresponding Hopf equation, as an equation for measures on the space of solenoidal distributions. We define equilibrium states as the solutions of the stationary Hopf equation. We find a class of equilibrium states which corresponds to a class of infinitely divisible distributions, and investigate the properties of gaussian and poissonian states. Equilibrium dynamics for a class of poissonian states is constructed by means of the Onsager vortex equations.
Quantum motion on two planes connected at one point
International Nuclear Information System (INIS)
Exner, P.; Seba, P.
1986-01-01
Free motion of a particle on the manifold which consists of two planes connected at one point is studied. The four-parameter family of admissible Hamiltonians is constructed by self-adjoint extensions of the free Hamiltonian with the singular point removed. The probability of penetration between the two parts of the configuration manifold is calculated. The results can be used as a model for quantum point-contact spectroscopy
The Synthesis of Force Closure Grasps in the Plane.
1985-09-01
TASK U Artificial Inteligence Laboratory AREA A WORK UN IT "NMUIERS ~( 545 Technology Square Cambridge, MA 02139 SI. CONTROLLING OFICE NAME ANO... ARTIFICIAL INThLLIX’ ENCE LABORATORY A. 1. Memo 861 September, 1985 The Synthesis of Force-Closure Grasps In the Plane DTIC ’VeL% ,#ECTE 1 VnDcNguyenU Abstract... Artificial In- telligenmcc Liabomatory of thle Massachuset Is hInsttute of Teclhnolog3 . Support for the Lahoratot * s Artificial Intelligence research is
Binary Labelings for Plane Quadrangulations and their Relatives
Felsner, Stefan; Huemer, Clemens; Kappes, Sarah; Orden, David
2006-01-01
Motivated by the bijection between Schnyder labelings of a plane triangulation and partitions of its inner edges into three trees, we look for binary labelings for quadrangulations (whose edges can be partitioned into two trees). Our labeling resembles many of the properties of Schnyder's one for triangulations: Apart from being in bijection with tree decompositions, paths in these trees allow to define the regions of a vertex such that counting faces in them yields an algorithm for embedding...
Soft Gravitons & the Memory Effect for Plane Gravitational Waves
Zhang, P. -M.; Duval, C.; Gibbons, G. W.; Horvathy, P. A.
2017-01-01
The "gravitational memory effect" due to an exact plane wave provides us with an elementary description of the diffeomorphisms associated with soft gravitons. It is explained how the presence of the latter may be detected by observing the motion of freely falling particles or other forms of gravitational wave detection. Numerical calculations confirm the relevance of the first, second and third time integrals of the Riemann tensor pointed out earlier. Solutions for various profiles are constr...
Frontal plane stability following UKA in a biomechanical study.
Heyse, Thomas J; Tucker, Scott M; Rajak, Yogesh; Kia, Mohammad; Lipman, Joseph D; Imhauser, Carl W; Westrich, Geoffrey H
2015-06-01
Function and kinematics following unicondylar knee arthroplasty (UKA) have been reported to be close to the native knee. Gait, stair climbing and activities of daily living expose the knee joint to a combination of varus and valgus moments. Replacement of the medial compartment via UKA is likely to change the physiologic knee stability and its ability to respond to varus and valgus moments. It was hypothesized that UKA implantation would stiffen the knee and decrease range of motion in the frontal plane. Six fresh frozen cadaver knees were prepared and mounted in a six-degrees-of-freedom robot. An axial load of 200 N was applied with the knee in 15°, 45° and 90° of flexion. Varus and valgus moments were added, respectively, before and after implantation of medial UKA. Tests were than redone with a thicker polyethylene inlay to simulate overstuffing of the medial compartment. Range of motion in the frontal plane and the tibial response to moments were recorded via the industrial robot. The range of motion in the frontal plane was decreased with both, balanced and overstuffed UKA and shifted towards valgus. When exposed to valgus moments, knees following UKA were stiffer in comparison with the native knee. The effect was even more pronounced with medial overstuffing. In UKA, the compressive anatomy is replaced by much stiffer components. This lack of medial compression and relative overstuffing leads to a tighter medial collateral ligament. This drives the trend towards a stiffer joint as documented by a decrease in frontal plane range of motion. Overstuffing should strictly be avoided when performing UKA.
Global structure of a polynomial autonomous system on the plane
International Nuclear Information System (INIS)
Nguyen Van Chau.
1991-10-01
This note is to study the global behaviour of a polynomial autonomous system on the plane with divergence non-positive outside a bounded set. It is shown that in some certain conditions the global structure of such system can be simple. The main result here can be seen as an improvement of the result of Olech and Meister concerning with the global asymptotical stable conjecture of Markur and Yamable and the Jacobian Conjecture. (author). 13 refs
Euler and Navier-Stokes equations on the hyperbolic plane.
Khesin, Boris; Misiolek, Gerard
2012-11-06
We show that nonuniqueness of the Leray-Hopf solutions of the Navier-Stokes equation on the hyperbolic plane (2) observed by Chan and Czubak is a consequence of the Hodge decomposition. We show that this phenomenon does not occur on (n) whenever n ≥ 3. We also describe the corresponding general Hamiltonian framework of hydrodynamics on complete Riemannian manifolds, which includes the hyperbolic setting.
Euler and Navier–Stokes equations on the hyperbolic plane
Khesin, Boris; Misiołek, Gerard
2012-01-01
We show that nonuniqueness of the Leray–Hopf solutions of the Navier–Stokes equation on the hyperbolic plane ℍ2 observed by Chan and Czubak is a consequence of the Hodge decomposition. We show that this phenomenon does not occur on ℍn whenever n ≥ 3. We also describe the corresponding general Hamiltonian framework of hydrodynamics on complete Riemannian manifolds, which includes the hyperbolic setting. PMID:23091015
Diffraction by a Conducting Half-Plane in a Chiroplasma
2000-09-29
34 Acta Physica Polonica A , vol. 83, no. 6, pp. 739-750, 1993. [5] S. Asghar and A . Lakhtakia, "Planewave diffraction by a perfectly conducting...UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADPO 11647 TITLE: Diffraction by a Conducting Half-Plane in a Chiroplasma...the component should be considered within [he context of the overall compilation report and not as a stand-alone technical report. The following
[Occlusal plane control in hyperdivergents: regarding one case].
Rerhrhaye, Wiam; Zaoui, Fatima; Aalloula, El Housseine
2009-06-01
Management of occlusal plane inclination in the sagittal dimension is one of the main concerns of practitioners. Inclination maintenance or correction can condition the success and stability of treatment. By means of a clinical case, we will attempt to discuss the different aspects of management from diagnosis to treatment, bearing in mind the local and regional context. The adopted treatment plan takes into consideration the functional and esthetic issues specific to Moroccan patients without neglecting soft tissue harmony.
Diffusion of heat from a finite, rectangular, plane heat source
International Nuclear Information System (INIS)
Ferreri, J.C.; Caballero, C.H.
1985-01-01
Non-dimensional results for the temperature field originating in a rectangular, finite, plane heat source with infinitesimal thickness are introduced. The source decays in time, zero decay being a particular case. Results are useful for obtaining an aproximation of the maximum temperature of a system holding an internal heat source. The range selected for the parameters is specially useful in the case of a nuclear waste repository. The application to the case of mass diffussion arises from analogy. (Author) [es
Traveling Wave Modes of a Plane Layered Anelastic Earth
2016-05-20
grant, “Coupled Modes in Elastic Bottoms” (1) is the publication “Traveling wave modes of a plane layered anelastic earth ” accepted for...anelastic earth Robert I. Odom Applied Physics Laboratory and Department of Earth and Space Sciences University of Washington, 1013 NE 40th St., Seattle...contrast to a similar standing wave problem for the earth free oscillations (Tromp and Dahlen, 1990). Attenuation is commonly incorporated into synthetic
State-plane analysis of parallel resonant converter
Oruganti, R.; Lee, F. C.
1985-01-01
A method for analyzing the complex operation of a parallel resonant converter is developed, utilizing graphical state-plane techniques. The comprehensive mode analysis uncovers, for the first time, the presence of other complex modes besides the continuous conduction mode and the discontinuous conduction mode and determines their theoretical boundaries. Based on the insight gained from the analysis, a novel, high-frequency resonant buck converter is proposed. The voltage conversion ratio of the new converter is almost independent of load.
Algebraic invariant curves of plane polynomial differential systems
Tsygvintsev, Alexei
2001-01-01
We consider a plane polynomial vector field P(x,y) dx + Q(x,y) dy of degree m>1. With each algebraic invariant curve of such a field we associate a compact Riemann surface with the meromorphic differential ω = dx/P = dy/Q. The asymptotic estimate of the degree of an arbitrary algebraic invariant curve is found. In the smooth case this estimate has already been found by Cerveau and Lins Neto in a different way.
Active point out-of-plane ultrasound calibration
Cheng, Alexis; Guo, Xiaoyu; Zhang, Haichong K.; Kang, Hyunjae; Etienne-Cummings, Ralph; Boctor, Emad M.
2015-03-01
Image-guided surgery systems are often used to provide surgeons with informational support. Due to several unique advantages such as ease of use, real-time image acquisition, and no ionizing radiation, ultrasound is a common intraoperative medical imaging modality used in image-guided surgery systems. To perform advanced forms of guidance with ultrasound, such as virtual image overlays or automated robotic actuation, an ultrasound calibration process must be performed. This process recovers the rigid body transformation between a tracked marker attached to the transducer and the ultrasound image. Point-based phantoms are considered to be accurate, but their calibration framework assumes that the point is in the image plane. In this work, we present the use of an active point phantom and a calibration framework that accounts for the elevational uncertainty of the point. Given the lateral and axial position of the point in the ultrasound image, we approximate a circle in the axial-elevational plane with a radius equal to the axial position. The standard approach transforms all of the imaged points to be a single physical point. In our approach, we minimize the distances between the circular subsets of each image, with them ideally intersecting at a single point. We simulated in noiseless and noisy cases, presenting results on out-of-plane estimation errors, calibration estimation errors, and point reconstruction precision. We also performed an experiment using a robot arm as the tracker, resulting in a point reconstruction precision of 0.64mm.
Parallax handling of image stitching using dominant-plane homography
Pang, Zhaofeng; Li, Cheng; Zhao, Baojun; Tang, Linbo
2015-10-01
In this paper, we present a novel image stitching method to handle parallax in practical application. For images with significant amount of parallax, the more effective approach is to align roughly and globally the overlapping regions and then apply a seam-cutting method to composite naturally stitched images. It is well known that images can be modeled by various planes result from the projective parallax under non-ideal imaging condition. The dominant-plane homography has important advantages of warping an image globally and avoiding some local distortions. The proposed method primarily addresses large parallax problem through two steps: (1) selecting matching point pairs located on the dominant plane, by clustering matching correspondences and then measuring the cost of each cluster; and (2) in order to obtain a plausible seam, edge maps of overlapped area incorporation arithmetic is adopted to modify the standard seam-cutting method. Furthermore, our approach is demonstrated to achieve reliable performance of handling parallax through a mass of experimental comparisons with state-of-the-art methods.
Plane-wave Least-squares Reverse Time Migration
Dai, Wei
2012-11-04
Least-squares reverse time migration is formulated with a new parameterization, where the migration image of each shot is updated separately and a prestack image is produced with common image gathers. The advantage is that it can offer stable convergence for least-squares migration even when the migration velocity is not completely accurate. To significantly reduce computation cost, linear phase shift encoding is applied to hundreds of shot gathers to produce dozens of planes waves. A regularization term which penalizes the image difference between nearby angles are used to keep the prestack image consistent through all the angles. Numerical tests on a marine dataset is performed to illustrate the advantages of least-squares reverse time migration in the plane-wave domain. Through iterations of least-squares migration, the migration artifacts are reduced and the image resolution is improved. Empirical results suggest that the LSRTM in plane wave domain is an efficient method to improve the image quality and produce common image gathers.
An evaluation of in-plane shields during thoracic CT.
Foley, S J; McEntee, M F; Rainford, L A
2013-08-01
The object of this study was to compare organ dose and image quality effects of using bismuth and barium vinyl in-plane shields with standard and low tube current thoracic CT protocols. A RANDO phantom was scanned using a 64-slice CT scanner and three different thoracic protocols. Thermoluminescent dosemeters were positioned in six locations to record surface and absorbed breast and lung doses. Image quality was assessed quantitatively using region of interest measurements. Scanning was repeated using bismuth and barium vinyl in-plane shields to cover the breasts and the results were compared with standard and reduced dose protocols. Dose reductions were most evident in the breast, skin and anterior lung when shielding was used, with mean reductions of 34, 33 and 10 % for bismuth and 23, 18 and 11 % for barium, respectively. Bismuth was associated with significant increases in both noise and CT attenuation values for all the three protocols, especially anteriorly and centrally. Barium shielding had a reduced impact on image quality. Reducing the overall tube current reduced doses in all the locations by 20-27 % with similar increases in noise as shielding, without impacting on attenuation values. Reducing the overall tube current best optimises dose with minimal image quality impact. In-plane shields increase noise and attenuation values, while reducing anterior organ doses primarily. Shielding remains a useful optimisation tool in CT and barium is an effective alternative to bismuth especially when image quality is of concern.
Homogeneous Ir-192 afterloading-flab-irradiation of plane surfaces
International Nuclear Information System (INIS)
Bratengeier, K.; Krieger, T.
2002-01-01
Homogeneous irradiation of plane targets bt Ir-192 afterloading flabs made by a parallel series of linear applicators can be time-consuming even with modern planning systems. The aim of the present study was to develop an algorithm that supplies homogeneous dose distributions in an arbitrary given plane in parallel to the equipped plane of a flab. The edge and corner positions of the flab are of particular importance. The identity of the dose in the optimisation distance above the flab centre, corners, and middle of the flab edges, leads to a strict relation of the respective dwell weights. Formulas can be derived that allow the calculation of the dwell times. The dimensioning of the flab can be rapidly adapted to new conditions. A comparison with the results of Nucletron PLATO-BPS for applicator-applicator distances and step sizes of 1 cm at optimisation distances of 10, 20, 30, and 40 mm and various flab sizes (3 x 3, 9 x 9, and 15 x 15 cm 2 ) shows the following results: The standard deviation of the proposed algorithm is sometimes slightly higher than the results of the commercial planning system, whereas the underdosage at the flab edges is usually smaller. The effort for planning and preparation of the irradiation, for example using a Nucletron HDR, is below 5 minutes - a considerable reduction of planning time. (orig.) [de
Application of morphological bit planes in retinal blood vessel extraction.
Fraz, M M; Basit, A; Barman, S A
2013-04-01
The appearance of the retinal blood vessels is an important diagnostic indicator of various clinical disorders of the eye and the body. Retinal blood vessels have been shown to provide evidence in terms of change in diameter, branching angles, or tortuosity, as a result of ophthalmic disease. This paper reports the development for an automated method for segmentation of blood vessels in retinal images. A unique combination of methods for retinal blood vessel skeleton detection and multidirectional morphological bit plane slicing is presented to extract the blood vessels from the color retinal images. The skeleton of main vessels is extracted by the application of directional differential operators and then evaluation of combination of derivative signs and average derivative values. Mathematical morphology has been materialized as a proficient technique for quantifying the retinal vasculature in ocular fundus images. A multidirectional top-hat operator with rotating structuring elements is used to emphasize the vessels in a particular direction, and information is extracted using bit plane slicing. An iterative region growing method is applied to integrate the main skeleton and the images resulting from bit plane slicing of vessel direction-dependent morphological filters. The approach is tested on two publicly available databases DRIVE and STARE. Average accuracy achieved by the proposed method is 0.9423 for both the databases with significant values of sensitivity and specificity also; the algorithm outperforms the second human observer in terms of precision of segmented vessel tree.
Achromatic Focal Plane Mask for Exoplanet Imaging Coronagraphy
Newman, Kevin Edward; Belikov, Ruslan; Guyon, Olivier; Balasubramanian, Kunjithapatham; Wilson, Dan
2013-01-01
Recent advances in coronagraph technologies for exoplanet imaging have achieved contrasts close to 1e10 at 4 lambda/D and 1e-9 at 2 lambda/D in monochromatic light. A remaining technological challenge is to achieve high contrast in broadband light; a challenge that is largely limited by chromaticity of the focal plane mask. The size of a star image scales linearly with wavelength. Focal plane masks are typically the same size at all wavelengths, and must be sized for the longest wavelength in the observational band to avoid starlight leakage. However, this oversized mask blocks useful discovery space from the shorter wavelengths. We present here the design, development, and testing of an achromatic focal plane mask based on the concept of optical filtering by a diffractive optical element (DOE). The mask consists of an array of DOE cells, the combination of which functions as a wavelength filter with any desired amplitude and phase transmission. The effective size of the mask scales nearly linearly with wavelength, and allows significant improvement in the inner working angle of the coronagraph at shorter wavelengths. The design is applicable to almost any coronagraph configuration, and enables operation in a wider band of wavelengths than would otherwise be possible. We include initial results from a laboratory demonstration of the mask with the Phase Induced Amplitude Apodization coronagraph.
Scattering on plane waves and the double copy
Adamo, Tim; Casali, Eduardo; Mason, Lionel; Nekovar, Stefan
2018-01-01
Perturbatively around flat space, the scattering amplitudes of gravity are related to those of Yang–Mills by colour-kinematic duality, under which gravitational amplitudes are obtained as the ‘double copy’ of the corresponding gauge theory amplitudes. We consider the question of how to extend this relationship to curved scattering backgrounds, focusing on certain ‘sandwich’ plane waves. We calculate the 3-point amplitudes on these backgrounds and find that a notion of double copy remains in the presence of background curvature: graviton amplitudes on a gravitational plane wave are the double copy of gluon amplitudes on a gauge field plane wave. This is non-trivial in that it requires a non-local replacement rule for the background fields and the momenta and polarization vectors of the fields scattering on the backgrounds. It must also account for new ‘tail’ terms arising from scattering off the background. These encode a memory effect in the scattering amplitudes, which naturally double copies as well.
HIGH PERFORMANCE PIAA CORONAGRAPHY WITH COMPLEX AMPLITUDE FOCAL PLANE MASKS
International Nuclear Information System (INIS)
Guyon, Olivier; Martinache, Frantz; Belikov, Ruslan; Soummer, Remi
2010-01-01
We describe a coronagraph approach where the performance of a Phase-Induced Amplitude Apodization (PIAA) coronagraph is improved by using a partially transmissive phase-shifting focal plane mask and a Lyot stop. This approach combines the low inner working angle offered by phase mask coronagraphy, the full throughput and uncompromized angular resolution of the PIAA approach, and the design flexibility of Apodized Pupil Lyot Coronagraph. A PIAA complex mask coronagraph (PIAACMC) is fully described by the focal plane mask size, or, equivalently, its complex transmission which ranges from 0 (opaque) to -1 (phase shifting). For all values of the transmission, the PIAACMC theoretically offers full on-axis extinction and 100% throughput at large angular separations. With a pure phase focal plane mask (complex transmission = -1), the PIAACMC offers 50% throughput at 0.64 λ/D while providing total extinction of an on-axis point source. This performance is very close to the 'fundamental performance limit' of coronagraphy derived from first principles. For very high contrast level, imaging performance with PIAACMC is in practice limited by the angular size of the on-axis target (usually a star). We show that this fundamental limitation must be taken into account when choosing the optimal value of the focal plane mask size in the PIAACMC design. We show that the PIAACMC enables visible imaging of Jupiter-like planets at ∼1.2 λ/D from the host star, and can therefore offer almost three times more targets than a PIAA coronagraph optimized for this type of observation. We find that for visible imaging of Earth-like planets, the PIAACMC gain over a PIAA is probably much smaller, as coronagraphic performance is then strongly constrained by stellar angular size. For observations at 'low' contrast (below ∼ 10 8 ), the PIAACMC offers significant performance enhancement over PIAA. This is especially relevant for ground-based high contrast imaging systems in the near-IR, where
Determination of the Relative Positions of Three Planes: Action Research
Directory of Open Access Journals (Sweden)
Tuba Ada
2016-07-01
Full Text Available The purpose of this study was to explore how a more effective lesson plan and teaching environment can be achieved so as to improve elementary mathematics teacher candidates’ achievement in analytical examination of planes in space. In order to improve achievement in expressing the relative positions of three planes not only algebraically but also visually the study used an action research approach as planned by the researchers. In Implementation 1, the teacher candidates were given the equations of three planes and they were asked to determine the relative positions of the planes so that their prior knowledge could be identified. In this stage, the candidate teachers tried to determine the relative positions of the planes in one direction by examining the plane equations in pairs. In Implementation 2, the candidate teachers were asked to find the solution set of the linear equation system consisting of three equations with three unknowns and to come up with geometric interpretation of this solution. In this stage, some of the candidate teachers were able to solve the equation, but they couldn’t interpret it geometrically. In Implementation 3, Maple, a computer algebra system, was used so that the candidate teachers could visualize and observe the relative positions of the three planes by using the plane equations. In this stage, the candidate teachers associated the set of solutions of the plane equations with the three-dimensional images obtained with Maple. The results of the implementation showed that the proposed plan improved the mathematics teacher candidates’ visualization of the relative positions of the three planes.Keywords: planes in space, analytic geometry, Maple, action researchÜç Düzlemin Birbirine Göre Konumunun Belirlenmesi: Eylem AraştırmasıÖzBu çalışmanın amacı, ilköğretim Matematik öğretmen adaylarının uzayda düzlemlerin analitik incelenmesi konusundaki başarısını arttırmak için daha etkili
Plane-Casting: 3D Cursor Control with a SmartPhone
Katzakis, Nicholas; Kiyokawa, Kiyoshi; Hori, Masahiro; Takemura, Haruo
2018-01-01
We present Plane-Casting, a novel technique for 3D object manipulation from a distance that is especially suitable for smartphones. We describe two variations of Plane-Casting, Pivot and Free Plane-Casting, and present results from a pilot study. Results suggest that Pivot Plane-Casting is more suitable for quick, coarse movements whereas Free Plane-Casting is more suited to slower, precise motion. In a 3D movement task, Pivot Plane-Casting performed better quantitatively, but subjects prefer...
Niraj, G; Kelkar, Aditi; Hart, Elaine; Kaushik, Vipul; Fleet, Danny; Jameson, John
2015-11-01
Transversus abdominis plane (TAP) blocks have been reported to be an effective method of providing analgesia after abdominal surgery. To perform a prospective audit on the effectiveness of a novel technique of providing continuous transversus abdominis plane (TAP) analgesia in patients undergoing emergency and elective abdominal surgery. Prospective single center audit over a 3-year period. University hospital. One hundred twenty-four American Society of Anesthesiologists I to IV adult patients presenting for elective as well as emergency abdominal surgery in whom epidural analgesia was contraindicated or refused. Four quadrant TAP blocks and continuous TAP analgesia. Numerical rating scale pain scores at rest and on coughing, nausea scores, satisfaction scores, complications, frequency of analgesia failure, therapeutic failure with continuous TAP analgesia and opioid consumption. One hundred twenty-four patients who received continuous TAP analgesia were audited. This included 34 patients for elective open surgery, 36 patients for emergency laparotomy, and 54 patients who underwent elective laparoscopic colorectal surgery. Surgical incision was within the dermatomal limit of the block in 70% of the patients (88/124). Therapeutic failure with the technique was 10%. Frequency of analgesic failure over the 48-hour period was none in 39% and below 5 episodes in 57%. Four quadrant transversus abdominis plane blocks and continuous TAP analgesia is an effective technique for providing postoperative analgesia after abdominal surgery. It has the potential to be used as a sole analgesic technique when the surgical incision is within its dermatomal limit. Copyright © 2015 Elsevier Inc. All rights reserved.
Sadeghifar, Hamidreza
2018-05-01
The present study experimentally investigates the realistic functionality of in-plane and through-plane pressure drops of layered fibrous media with porosity, fiber diameter, fiber spacing, fiber-fiber angles and fiber-flow angles. The study also reveals that pressure drop may increase with porosity and fiber diameter under specific circumstances. This counter-intuitive point narrows down the validity range of widely-used permeability-porosity-diameter models or correlations. It is found that, for fibrous materials, the most important parameter that impacts the in-plane pressure drop is not their porosities but the number of fibers extended in the flow direction. It is also concluded that in-plane pressure drop is highly dependent upon the flow direction (fiber-flow angles), especially at lower porosities. Contrary to in-plane pressure drop, through-plane pressure drop is a weak function of fiber-fiber angles but is strongly impacted by fiber spacing, especially at lower porosities. At a given porosity, low through-plane pressure drops occur if fiber spacing does not change practically from one layer to another. Through-plane pressure drop also, insignificantly, increases with the intersecting angles between fibers. An optimized microstructure of fibrous media resulting in minimal in-plane and through-plane pressure drops is also offered for the first time in this work.
Hand-Eye LRF-Based Iterative Plane Detection Method for Autonomous Robotic Welding
Directory of Open Access Journals (Sweden)
Sungmin Lee
2015-12-01
Full Text Available This paper proposes a hand-eye LRF-based (laser range finder welding plane-detection method for autonomous robotic welding in the field of shipbuilding. The hand-eye LRF system consists of a 6 DOF manipulator and an LRF attached to the wrist of the manipulator. The welding plane is detected by the LRF with only the wrist's rotation to minimize a mechanical error caused by the manipulator's motion. A position on the plane is determined as an average position of the detected points on the plane, and a normal vector to the plane is determined by applying PCA (principal component analysis to the detected points. In this case, the accuracy of the detected plane is analysed by simulations with respect to the wrist's angle interval and the plane angle. As a result of the analysis, an iterative plane-detection method with the manipulator's alignment motion is proposed to improve the performance of plane detection. For verifying the feasibility and effectiveness of the proposed plane-detection method, experiments are carried out with a prototype of the hand-eye LRF-based system, which consists of a 1 DOF wrist's joint, an LRF system and a rotatable plane. In addition, the experimental results of the PCA-based plane detection method are compared with those of the two representative plane-detection methods, based on RANSAC (RANdom SAmple Consensus and the 3D Hough transform in both accuracy and computation time's points of view.
Damstra, Janalt; Fourie, Zacharias; De Wit, Marnix; Ren, Yijin
2012-02-01
Morphometric methods are used in biology to study object symmetry in living organisms and to determine the true plane of symmetry. The aim of this study was to determine if there are clinical differences between three-dimensional (3D) cephalometric midsagittal planes used to describe craniofacial asymmetry and a true symmetry plane derived from a morphometric method based on visible facial features. The sample consisted of 14 dry skulls (9 symmetric and 5 asymmetric) with metallic markers which were imaged with cone-beam computed tomography. An error study and statistical analysis were performed to validate the morphometric method. The morphometric and conventional cephalometric planes were constructed and compared. The 3D cephalometric planes constructed as perpendiculars to the Frankfort horizontal plane resembled the morphometric plane the most in both the symmetric and asymmetric groups with mean differences of less than 1.00 mm for most variables. However, the standard deviations were often large and clinically significant for these variables. There were clinically relevant differences (>1.00 mm) between the different 3D cephalometric midsagittal planes and the true plane of symmetry determined by the visible facial features. The difference between 3D cephalometric midsagittal planes and the true plane of symmetry determined by the visible facial features were clinically relevant. Care has to be taken using cephalometric midsagittal planes for diagnosis and treatment planning of craniofacial asymmetry as they might differ from the true plane of symmetry as determined by morphometrics.
Coupled fracture modes under anti-plane loading
Directory of Open Access Journals (Sweden)
Les P. Pook
2016-07-01
Full Text Available The linear elastic analysis of homogeneous, isotropic cracked bodies is a Twentieth Century development. It was recognised that the crack tip stress field is a singularity, but it was not until the introduction of the essentially two dimensional stress intensity factor concept in 1957 that widespread application to practical engineering problems became possible. The existence of three dimensional corner point effects in the vicinity of a corner point where a crack front intersects a free surface was investigated in the late 1970s: it was found that modes II and III cannot exist in isolation. The existence of one of these modes always induces the other. An approximate solution for corner point singularities by Bažant and Estenssoro explained some features of corner point effects but there were various paradoxes and inconsistencies. In an attempt to explain these a study was carried out on the coupled in-plane fracture mode induced by a nominal anti-plane (mode III loading applied to plates and discs weakened by a straight crack. The results derived from a large bulk of finite element models showed clearly that Bažant and Estenssoro’s analysis is incomplete. Some of the results of the study are summarised, together with some recent results for a disc under in-plane shear loading. On the basis of these results, and a mathematical argument, the results suggest that the stress field in the vicinity of a corner point is the sum of two singularities: one due to stress intensity factors and the other due to an as yet undetermined corner point singularity.
Kalman Filter for Calibrating a Telescope Focal Plane
Kang, Bryan; Bayard, David
2006-01-01
The instrument-pointing frame (IPF) Kalman filter, and an algorithm that implements this filter, have been devised for calibrating the focal plane of a telescope. As used here, calibration signifies, more specifically, a combination of measurements and calculations directed toward ensuring accuracy in aiming the telescope and determining the locations of objects imaged in various arrays of photodetectors in instruments located on the focal plane. The IPF Kalman filter was originally intended for application to a spaceborne infrared astronomical telescope, but can also be applied to other spaceborne and ground-based telescopes. In the traditional approach to calibration of a telescope, (1) one team of experts concentrates on estimating parameters (e.g., pointing alignments and gyroscope drifts) that are classified as being of primarily an engineering nature, (2) another team of experts concentrates on estimating calibration parameters (e.g., plate scales and optical distortions) that are classified as being primarily of a scientific nature, and (3) the two teams repeatedly exchange data in an iterative process in which each team refines its estimates with the help of the data provided by the other team. This iterative process is inefficient and uneconomical because it is time-consuming and entails the maintenance of two survey teams and the development of computer programs specific to the requirements of each team. Moreover, theoretical analysis reveals that the engineering/ science iterative approach is not optimal in that it does not yield the best estimates of focal-plane parameters and, depending on the application, may not even enable convergence toward a set of estimates.
Fabrication of a Cryogenic Bias Filter for Ultrasensitive Focal Plane
Chervenak, James; Wollack, Edward
2012-01-01
A fabrication process has been developed for cryogenic in-line filtering for the bias and readout of ultrasensitive cryogenic bolometers for millimeter and submillimeter wavelengths. The design is a microstripline filter that cuts out, or strongly attenuates, frequencies (10 50 GHz) that can be carried by wiring staged at cryogenic temperatures. The filter must have 100-percent transmission at DC and low frequencies where the bias and readout lines will carry signal. The fabrication requires the encapsulation of superconducting wiring in a dielectric-metal envelope with precise electrical characteristics. Sufficiently thick insulation layers with high-conductivity metal layers fully surrounding a patterned superconducting wire in arrayable formats have been demonstrated. A degenerately doped silicon wafer has been chosen to provide a metallic ground plane. A metallic seed layer is patterned to enable attachment to the ground plane. Thick silicon dioxide films are deposited at low temperatures to provide tunable dielectric isolation without degrading the metallic seed layer. Superconducting wiring is deposited and patterned using microstripline filtering techniques to cut out the relevant frequencies. A low Tc superconductor is used so that it will attenuate power strongly above the gap frequency. Thick dielectric is deposited on top of the circuit, and then vias are patterned through both dielectric layers. A thick conductive film is deposited conformally over the entire circuit, except for the contact pads for the signal and bias attachments to complete the encapsulating ground plane. Filters are high-aspect- ratio rectangles, allowing close packing in one direction, while enabling the chip to feed through the wall of a copper enclosure. The chip is secured in the copper wall using a soft metal seal to make good thermal and electrical contact to the outer shield.
A cephalometric study to determine the plane of occlusion in completely edentulous patients.
Hindocha, Amit D; Vartak, Vikas N; Bhandari, Aruna J; Dudani, Mohit T
2013-01-01
Determination of the plane of occlusion in completely edentulous patients with the help of the ala-tragus line (Camper's plane) may be questioned. An attempt to devise an alternative method to determine the orientation of the plane of occlusion was made. Cephalometric analysis was used to identify whether a correlation exists between the plane of occlusion of dentulous Indian individuals and other stable cranial landmarks. A negative correlation was found to exist between the occlusal Plane-FH plane angle and the porion-nasion-anterior nasal spine (PoNANS) angle. From the derived mathematical correlation, it was concluded that the angulation of the occlusal plane in completely edentulous subjects may be determined by taking a cephalogram at the diagnostic stage. Further, the clinical applicability of the derived mathematical formula (while determining the plane of occlusion) was tested on completely edentulous patients.
Back Radiation Suppression through a Semitransparent Ground Plane for a mm-Wave Patch Antenna
Klionovski, Kirill; Shamim, Atif
2017-01-01
by a round semitransparent ground plane. The semitransparent ground plane has been realized using a low-cost carbon paste on a Kapton film. Experimental results match closely with those of simulations and validate the overall concept.
16 CFR Figure 5 to Subpart A of... - Zero Reference Point Related to Detecting Plane
2010-01-01
... Plane 5 Figure 5 to Subpart A of Part 1209 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS INTERIM SAFETY STANDARD FOR CELLULOSE INSULATION The Standard Pt... Plane EC03OC91.035 ...
16 CFR Figure 3 to Part 1203 - Location of Reference Plane
2010-01-01
... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Location of Reference Plane 3 Figure 3 to Part 1203 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT... Plane ER10MR98.003 ...
Out-of-plane coercive field of Ni80Fe20 antidot arrays
International Nuclear Information System (INIS)
Gao Chunhong; Chen Ke; Lue Ling; Zhao Jianwei; Chen Peng
2010-01-01
The out-of-plane magnetic anisotropy and out-of-plane magnetization reversal process of nanoscale Ni 80 Fe 20 antidot arrays deposited by magnetron sputtering technique on an anodic aluminum oxide (AAO) membrane are investigated. The angular dependence of out-of-plane remanent magnetization of Ni 80 Fe 20 antidot arrays shows that the maximum remanence is in-plane and the squareness of the out-of-plane hysteresis loop follow a |cos θ| dependence. The angular dependence of out-of-plane coercivity of Ni 80 Fe 20 antidot arrays shows that the maximum coercivity lies on the surface of a cone with its symmetric axis normal to the sample plane, which indicates a transition of magnetic reversal from curling to coherent rotation when changing the angle between the applied magnetic field and the sample plane.
Out-of-plane coercive field of Ni 80Fe 20 antidot arrays
Gao, Chunhong; Chen, Ke; Lü, Ling; Zhao, Jianwei; Chen, Peng
2010-11-01
The out-of-plane magnetic anisotropy and out-of-plane magnetization reversal process of nanoscale Ni 80Fe 20 antidot arrays deposited by magnetron sputtering technique on an anodic aluminum oxide (AAO) membrane are investigated. The angular dependence of out-of-plane remanent magnetization of Ni 80Fe 20 antidot arrays shows that the maximum remanence is in-plane and the squareness of the out-of-plane hysteresis loop follow a |cos θ| dependence. The angular dependence of out-of-plane coercivity of Ni 80Fe 20 antidot arrays shows that the maximum coercivity lies on the surface of a cone with its symmetric axis normal to the sample plane, which indicates a transition of magnetic reversal from curling to coherent rotation when changing the angle between the applied magnetic field and the sample plane.
Influence of the narrow {111} planes on axial and planar ion channeling.
Motapothula, M; Dang, Z Y; Venkatesan, T; Breese, M B H; Rana, M A; Osman, A
2012-05-11
We report channeling patterns where clearly resolved effects of the narrow {111} planes are observed in axial and planar alignments for 2 MeV protons passing through a 55 nm [001] silicon membrane. At certain axes, such as and , the offset in atomic rows forming the narrow {111} planes results in shielding from the large potential at the wide {111} planes, producing a region of shallow, asymmetric potential from which axial channeling patterns have no plane of symmetry. At small tilts from such axes, different behavior is observed from the wide and narrow {111} planes. At planar alignment, distinctive channeling effects due to the narrow planes are observed. As a consequence of the shallow potential well at the narrow planes, incident protons suffer dechanneled trajectories which are excluded from channeling within the wide planes, resulting in an anomalously large scattered beam at {111} alignment.
Near infrared focal plane for the ISOCAM camera
International Nuclear Information System (INIS)
Epstein, G.; Stefanovitch, D.; Tiphene, D.; Carpentier, Y.; Lorans, D.
1988-01-01
ISOCAM is one of the science instruments in the Infrared Space Observatory. It is a 2-channel IR Astronomical Imager intended to observe at very low flux levels, thanks to the use of a liquid helium cooled telescope. This paper describes the Focal Plane Assembly design of the short wavelength channel. The operation of a 32 x 32 InSb CID-SAT array detector has been demonstrated. The problems encountered in the design of the cooled electronics and the component selection process are discussed in the light of specific ISO constraints, such as thermal control and radiation shielding. 6 references
Planes internacionales, ideas educativas y poder político
Rambla, Francesc Xavier,
2012-01-01
Varios organismos internacionales han adoptado planes educativos decenales o quincenales cuyo plazo termina en la próxima década. Por ejemplo, la UNESCO es la entidad coordinadora del programa destinado a consolidar una Educación para Todos en 2015; a su vez, la Estrategia 2020 de la Unión Europea y las Metas Educativas de la Organización de Estados Iberoamericanos han comprometido a los países miembros de estas regiones mundiales a evaluar sus indicadores educativos hacia 2020-21. Igualmente...
c-Plane oriented Bi-oxide superconductor
International Nuclear Information System (INIS)
Kugimiya, K.; Kawashima, S.; Inoue, O.; Adachi, S.
1988-01-01
A newly found Bi-Sr-Ca-Cu-O superconductor with T c =80 K was synthesized in an almost pure phase. It is a laminar oxide with an Aurivillius phase and easily breaks into thin flakes. By slip-casting the flakes under pressure or by hot-pressing sintered bodies of isostatically formed green compacts, c-planes of the phase were highly oriented by more than 95%, mostly 98.5%. Sintered compacts generally contained materials with T c of 80 and 110 K as proved by the Meissner effect. 11 refs.; 6 figs
Fluorescence intensity dependence on the propagation plane inclination
International Nuclear Information System (INIS)
Fernandez, J.E.; Rubio, Marcelo; Sanchez, H.J.
1987-01-01
A Monte Carlo simulation of the primary and secondary X-ray fluorescent emission from an homogeneous and infinite thickness sample, irradiated under different inclination of the propagation plane, is carried out. An agreement with the predictions based on Sherman equations depending on the inclination angle α was found. The invariance of the primary fluorescence with respect to α and the decrease until evanescence of the secondary fluorescence for a α → π/2 are confirmed. A discussion about the physical basis of this dependence is carried out. Similar results are expected for tertiary fluorescence. (Author) [es
On the energy-momentum density of gravitational plane waves
International Nuclear Information System (INIS)
Dereli, T; Tucker, R W
2004-01-01
By embedding Einstein's original formulation of general relativity into a broader context, we show that a dynamic covariant description of gravitational stress-energy emerges naturally from a variational principle. A tensor T G is constructed from a contraction of the Bel tensor with a symmetric covariant second degree tensor field Φ and has a form analogous to the stress-energy tensor of the Maxwell field in an arbitrary spacetime. For plane-fronted gravitational waves helicity-2 polarized (graviton) states can be identified carrying non-zero energy and momentum
Path integral for Dirac particle in plane wave field
International Nuclear Information System (INIS)
Zeggari, S.; Boudjedaa, T.; Chetouani, L.
2001-01-01
The problem of a relativistic spinning particle in interaction with an electromagnetic plane wave field is treated via path integrals. The dynamics of the spin of the particle is described using the supersymmetric action proposed by Fradkin and Gitman. The problem has been solved by using two identities, one bosonic and the other fermionic, which are related directly to the classical equations of motion. The exact expression of the relative Green's function is given and the result agrees with those of the literature. Further, the suitably normalized wave functions are also extracted. (orig.)
Path integral for Dirac particle in plane wave field
Energy Technology Data Exchange (ETDEWEB)
Zeggari, S.; Boudjedaa, T.; Chetouani, L. [Mentouri Univ., Constantine (Algeria). Dept. of Physique
2001-10-01
The problem of a relativistic spinning particle in interaction with an electromagnetic plane wave field is treated via path integrals. The dynamics of the spin of the particle is described using the supersymmetric action proposed by Fradkin and Gitman. The problem has been solved by using two identities, one bosonic and the other fermionic, which are related directly to the classical equations of motion. The exact expression of the relative Green's function is given and the result agrees with those of the literature. Further, the suitably normalized wave functions are also extracted. (orig.)
Circularly Polarized Slotted Microstrip Patch Antenna with Finite Ground Plane
Directory of Open Access Journals (Sweden)
Sanyog Rawat
2012-12-01
Full Text Available In this paper a new geometry of circularly polarized patch antenna is proposed with improved bandwidth. The radiation performance of proposed patch antenna is investigated using IE3D simulation software and its performance is compared with that of conventional rectangular patch antenna. The simulated return loss, axial ratio and impedance with frequency for the proposed antenna are reported in this paper. It is shown that by selecting suitable ground-plane dimensions, air gap and location of the slots, the impedance bandwidth can be enhanced upto 10.15% as compared to conventional rectangular patch (4.24% with an axial ratio bandwidth of 4.05%.
Plane and hemispherical potential structures in magnetically expanding plasmas
International Nuclear Information System (INIS)
Takahashi, Kazunori; Igarashi, Yuichi; Fujiwara, Tamiya
2010-01-01
Two-dimensional potential structures are measured for different gas pressure in expanding argon plasma using permanent magnets, where the magnetic field is about 100 G in the source and several gauss in the diffusion chamber. The plane potential drop is observed near the source exit for 0.35 mTorr, while the potential structure becomes hemispherical when increasing up to 1 mTorr; the hemispherical structure results in the radial divergence of the ion beam. It is found that the trajectories of the accelerated ions and the electrons overcoming the potential drop are dominated by the potential structure and magnetic-field lines, respectively.
Effects of Geometry on the Steady Performance of Planing Hulls
DEFF Research Database (Denmark)
Wagner, M. K.; Andersen, Poul
2003-01-01
A vortex-lattice method is applied to planing hull forms. The geometry of the jet surfaces next to the wetted hull is estimated on the basis of the hull geometry while its sidewise extent has been found numerically applying a non-linear free-surface pressure condition in the jet region. The method...... is applied to practical hull forms with chines spray rails and with varying deadrise over the length of the boat. The deadrise variation has a large influence on lift and drag. For a design situation, where the total lift and centre of effort is given, the influence on the total drag is less due to change...
New focal plane detector system for the broad range spectrometer
International Nuclear Information System (INIS)
Sjoreen, T.P.
1984-01-01
A focal plane detector system consisting of a vertical drift chamber, parallel plate avalanche counters, and an ionization chamber with segmented anodes has been installed in the Broad Range Spectrometer at the Holifield Facility at Oak Ridge. The system, which has been designed for use with light-heavy ions with energies ranging from 10 to 25 MeV/amu, has a position resolution of approx. 0.1 mm, a scattering angle resolution of approx. 3 mrad, and a mass resolution of approx. 1/60
Electromagnetic forces and torques in nanoparticles irradiated by plane waves
International Nuclear Information System (INIS)
Garcia de Abajo, F.J.
2004-01-01
Optical tweezers and optical lattices are making it possible to control small particles by means of electromagnetic forces and torques. In this context, a method is presented in this work to calculate electromagnetic forces and torques for arbitrarily-shaped objects in the presence of other objects illuminated by a plane wave. The method is based upon an expansion of the electromagnetic field in terms of multipoles around each object, which are in turn used to derive forces and torques analytically. The calculation of multipole coefficients are obtained numerically by means of the boundary element method. Results are presented for both spherical and non-spherical objects
SIGMARZ, Stress Analysis of Axisymmetric or Plane Structures
International Nuclear Information System (INIS)
1978-01-01
1 - Nature of the physical problem solved: Classic stress analysis program for axisymmetric or plane geometric structures. 2 - Method of solution: The finite element method is used. Input are the finite element nodes, the imposed displacements, the applied forces at the nodes and the volumetric distributed forces. The linear equation system is solved by the Cholesky method. 3 - Restrictions on the complexity of the problem: Maximum number of nodes: 800; Maximum number of elements: 1300; Maximum number of displacements: 300; Maximum band width: 72
The minimal access deep plane extended vertical facelift.
Jacono, Andrew A; Parikh, Sachin S
2011-11-01
Modern facelift techniques have benefited from a "repopularization" of shorter incisions, limited skin elevation, and more limited dissection of the superficial musculoaponeurotic system (SMAS) and platysma in order to shorten postoperative recovery times and reduce surgical risks for patients. The authors describe their minimal access deep plane extended (MADE) vertical vector facelift, which is a hybrid technique combining the optimal features of the deep plane facelift and the short scar, minimal access cranial suspension (MACS) lift. The authors retrospectively reviewed the case records of 181 patients who underwent facelift procedures performed by the senior author (AAJ) during a two year period between March 2008 and March 2010. Of those patients, 153 underwent facelifting with the MADE vertical technique. With this technique, deep plane dissection releases the zygomatico-cutaneous ligaments, allowing for more significant vertical motion of the midface and jawline during suspension. Extended platysmal dissection was utilized with a lateral platysmal myotomy, which is not traditionally included in a deep plane facelift. The lateral platysmal myotomy allowed for separation of the vertical vector of suspension in the midface and jawline from the superolateral vector of suspension that is required for neck rejuvenation, obviating the need for additional anterior platysmal surgery. The average age of the patients was 57.8 years. The average length of follow-up was 12.7 months. In 69 consecutive patients from this series, average vertical skin excision measured 3.02 cm on each side of the face at the junction of the pre auricular and temporal hair tuft incision (resulting in a total excision of 6.04 cm of skin). Data from the entire series revealed a revision rate of 3.9%, a hematoma rate of 1.9%, and a temporary facial nerve injury rate of 1.3%. The common goal of all facelifting procedures is to provide a long-lasting, natural, balanced, rejuvenated aesthetic
Non-relativistic scalar field on the quantum plane
International Nuclear Information System (INIS)
Jahan, A.
2005-01-01
We apply the coherent state approach to the non-commutative plane to check the one-loop finiteness of the two-point and four-point functions of a non-relativistic scalar field theory in 2+1 dimensions. We show that the two-point and four-point functions of the model are finite at one-loop level and one recovers the divergent behavior of the model in the limit θ->0 + by appropriate redefinition of the non-commutativity parameter
Energy Relations for Plane Waves Reflected from Moving Media
DEFF Research Database (Denmark)
Daly, P.; Gruenberg, Harry
1967-01-01
When a plane wave is obliquely incident from vacuum on a semi-infinite moving medium, the energy flow carried by the incident wave, is in general, not carried away by the reflected and transmitted waves. This is only the case when the medium velocity is parallel to its vacuum interface. Otherwise...... there is a net inflow or outflow of electromagnetic energy, which can be accounted for by the change of stored energy in the system, and the work done by the mechanical forces acting on the medium. A detailed energy balance is drawn up for two different media moving normal to their vacuum interfaces: (a...
Focal plane array with modular pixel array components for scalability
Kay, Randolph R; Campbell, David V; Shinde, Subhash L; Rienstra, Jeffrey L; Serkland, Darwin K; Holmes, Michael L
2014-12-09
A modular, scalable focal plane array is provided as an array of integrated circuit dice, wherein each die includes a given amount of modular pixel array circuitry. The array of dice effectively multiplies the amount of modular pixel array circuitry to produce a larger pixel array without increasing die size. Desired pixel pitch across the enlarged pixel array is preserved by forming die stacks with each pixel array circuitry die stacked on a separate die that contains the corresponding signal processing circuitry. Techniques for die stack interconnections and die stack placement are implemented to ensure that the desired pixel pitch is preserved across the enlarged pixel array.
Tailoring distributed modal sensors for in-plane modal filtering
International Nuclear Information System (INIS)
Donoso, A; Bellido, J C
2009-01-01
In this note we deal with finding the shape of distributed piezoelectric modal sensors for isolating the in-plane mode shapes of plates. The problem is treated by an optimization approach, in which a binary function is used to model the design variable: the polarization profile of the piezoelectric layer. The numerical procedure proposed here allows us to find polarization profiles which take on two values only, i.e. either positive or negative polarization, that make it possible to isolate particular vibration modes in the frequency domain. (technical note)
Evacuation of children - movement on stairs and on Horizontal Plane
DEFF Research Database (Denmark)
Larusdottir, Aldis Run; Dederichs, Anne
2012-01-01
in full scale evacuation experiments where two age groups 0-2 years and 3-6 years were analyzed separately. It was found that flow through doors, walking speeds and densities were age-dependent and differed strongly from the data in existing literature. The results showed higher walking speeds in spiral...... slower in horizontal plane than adults, however they were keen to run during the evacuations, in the latter case their travel speed increased and exceeded the adults’. Since the evacuation characteristics of children differ in many ways from those of adults, nowadays models badly comprehend...
Multiple projection optical diffusion tomography with plane wave illumination
International Nuclear Information System (INIS)
Markel, Vadim A; Schotland, John C
2005-01-01
We describe a new data collection scheme for optical diffusion tomography in which plane wave illumination is combined with multiple projections in the slab imaging geometry. Multiple projection measurements are performed by rotating the slab around the sample. The advantage of the proposed method is that the measured data are more compatible with the dynamic range of most commonly used detectors. At the same time, multiple projections improve image quality by mutually interchanging the depth and transverse directions, and the scanned (detection) and integrated (illumination) surfaces. Inversion methods are derived for image reconstructions with extremely large data sets. Numerical simulations are performed for fixed and rotated slabs
Deformation energy of a toroidal nucleus and plane fragmentation barriers
International Nuclear Information System (INIS)
Fauchard, C.; Royer, G.
1996-01-01
The path leading to pumpkin-like configurations and toroidal shapes is investigated using a one-parameter shape sequence. The deformation energy is determined within the analytical expressions obtained for the various shape-dependent functions and the generalized rotating liquid drop model taking into account the proximity energy and the temperature. With increasing mass and angular momentum, a potential well appears in the toroidal shape path. For the heaviest systems, the pocket is large and locally favourable with respect to the plane fragmentation barriers which might allow the formation of evanescent toroidal systems which would rapidly decay in several fragments to minimize the surface tension. (orig.)
The classification of static plane-symmetric spacetimes
International Nuclear Information System (INIS)
Ziad, M.
1999-01-01
According to the classical literature, here a complete classification of static plane-symmetric spacetimes according to their isometries and metrics is provided,without imposing any restriction on the stress-energy tensor. It turns out that these spacetimes admit G r as the maximal isometry groups whereas their Killing vector fields are obtained. The Einstein field equations are used to discuss the stress energy tensors of the spacetimes admitting higher symmetries along with their Segre' and Plebanski types and finally results are compared with those of Taub, Hall and Steele
On the landau levels on the hyperbolic plane
International Nuclear Information System (INIS)
Comtet, A.
1986-04-01
The classical and quantum mechanics of a charged particle moving on the hyperbolic plane in a constant magnetic field is discussed. The underlying SL(2,R) symmetry leads to a general description of various possible trajectories. In contrast with the flat case, it is shown that closed orbits only arise for sufficiently strong fields. At the quantum level a group theoretical approach including both bound and continuum states is presented. It is shown that the semiclassical approximation leads to the exact bound state spectrum. The resolvent and its flat space limit are constructed in closed form
Diffuse scattering from laser-irradiated plane targets
International Nuclear Information System (INIS)
Kessel, C.G.M. van; Olsen, J.N.; Sachsenmaier, P.; Sigel, R.; Eidmann, K.; Godwin, R.P.
1976-11-01
Optical calorimetry of the laser radiation scattered from plane targets irradiated by 0.3 Joule/30 ps Nd-laser pulses with intensities up to 10 16 W cm -2 has been performed with an emphasis on diffuse scattering. Diffuse scattering outside the solid angle of the focusing lens is found to be a major reflection loss from the target. A fraction of 0.3 to 0.5 of the incident pulse energy was absorbed in the target with only a very weak dependence on pulse energy and target material. (orig.) [de
A plane mirror experiment inspired by a comic strip
Lúcio Prados Ribeiro, Jair
2016-01-01
A comic strip about a plane mirror was used in a high school optics test, and it was perceived that a large portion of the students believed that the mirror should be larger than the object so the virtual image could be entirely visible. Inspired on the comic strip, an experimental demonstration with flat mirrors was developed, in order to readdress this topic learning. Students were encouraged to create their own investigation of the phenomenon with a simple instrumental apparatus and also suggest different experimental approaches.
The H.E.S.S. Galactic plane survey
H. E. S. S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Benkhali, F. Ait; Angüner, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Tjus, J. Becker; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bonnefoy, S.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Carrigan, S.; Caroff, S.; Carosi, A.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Colafrancesco, S.; Condon, B.; Conrad, J.; Davids, I. D.; Decock, J.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Emery, G.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gallant, Y. A.; Garrigoux, T.; Gast, H.; Gaté, F.; Giavitto, G.; Giebels, B.; Glawion, D.; Glicenstein, J. F.; Gottschall, D.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holch, T. L.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Malyshev, D.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Ndiyavala, H.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poireau, V.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Rauth, R.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Rieger, F.; Rinchiuso, L.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Safi-Harb, S.; Sahakian, V.; Saito, S.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schandri, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Shiningayamwe, K.; Simoni, R.; Sol, H.; Spanier, F.; Spir-Jacob, M.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Steppa, C.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsirou, M.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Zorn, J.; Żywucka, N.
2018-04-01
We present the results of the most comprehensive survey of the Galactic plane in very high-energy (VHE) γ-rays, including a public release of Galactic sky maps, a catalog of VHE sources, and the discovery of 16 new sources of VHE γ-rays. The High Energy Spectroscopic System (H.E.S.S.) Galactic plane survey (HGPS) was a decade-long observation program carried out by the H.E.S.S. I array of Cherenkov telescopes in Namibia from 2004 to 2013. The observations amount to nearly 2700 h of quality-selected data, covering the Galactic plane at longitudes from ℓ = 250° to 65° and latitudes |b|≤ 3°. In addition to the unprecedented spatial coverage, the HGPS also features a relatively high angular resolution (0.08° ≈ 5 arcmin mean point spread function 68% containment radius), sensitivity (≲1.5% Crab flux for point-like sources), and energy range (0.2-100 TeV). We constructed a catalog of VHE γ-ray sources from the HGPS data set with a systematic procedure for both source detection and characterization of morphology and spectrum. We present this likelihood-based method in detail, including the introduction of a model component to account for unresolved, large-scale emission along the Galactic plane. In total, the resulting HGPS catalog contains 78 VHE sources, of which 14 are not reanalyzed here, for example, due to their complex morphology, namely shell-like sources and the Galactic center region. Where possible, we provide a firm identification of the VHE source or plausible associations with sources in other astronomical catalogs. We also studied the characteristics of the VHE sources with source parameter distributions. 16 new sources were previously unknown or unpublished, and we individually discuss their identifications or possible associations. We firmly identified 31 sources as pulsar wind nebulae (PWNe), supernova remnants (SNRs), composite SNRs, or gamma-ray binaries. Among the 47 sources not yet identified, most of them (36) have possible
Platform Isolation Using Out-of-Plane Complaint Mechanisms
Arevalo, A.
2014-10-08
This paper reports the structural solid mechanic simulation of a MEMS out-of-plane platform that provides thermal and electrical isolation for a device built on it. When assemble, the platform lifted for approximately 400 μm above the substrate level. A mechanical stress analysis is then presented in order to evaluate the feasibility of building it using commonly used materials in MEMS. Our analysis showed that polymeric materials such as polyimide and SU8 may undergo a localized plastic deformation but are not likely to fail upon assembly. Polysilicon on the contrary, showed high failure probability.
Platform Isolation Using Out-of-Plane Complaint Mechanisms
Arevalo, A.; Rawashdeh, E.; Foulds, I. G.
2014-01-01
This paper reports the structural solid mechanic simulation of a MEMS out-of-plane platform that provides thermal and electrical isolation for a device built on it. When assemble, the platform lifted for approximately 400 μm above the substrate level. A mechanical stress analysis is then presented in order to evaluate the feasibility of building it using commonly used materials in MEMS. Our analysis showed that polymeric materials such as polyimide and SU8 may undergo a localized plastic deformation but are not likely to fail upon assembly. Polysilicon on the contrary, showed high failure probability.
In-Plane Vibrations of Circular Curved Beams with a Transverse Open Crack
Öz, H. R.; Daş, M. T.
2006-01-01
In this study, the in plane vibrations of cracked circular curved beams is investigated. The beam is an Euler-Bernoulli beam. Only bending and extension effects are included. The curvature is in a single plane. In plane vibrations is analyzed using FEM. In the analysis, elongation, bending and rotary inertia effects are included. Four degrees of freedom for in-plane vibrations is assumed. Natural frequencies of the beam with a crack in different locations and depths are calculated using FEM. ...
A characterization of the desarguesian planes of order q2 by SL(2,q
Directory of Open Access Journals (Sweden)
D. A. Foulser
1983-01-01
Full Text Available The main result is that if the translation complement of a translation plane of order q2 contains a group isomorphic to SL(2,q and if the subgroups of order q are elations (shears, then the plane is Desarguesian. This generalizes earlier work of Walker, who assumed that the kernel of the plane contained GF(q.
Towards the design of a RF-harvesting EBG ground plane
Visser, H.J.; Keyrouz, S.
2015-01-01
Electromagnetic Band Gap (EBG) structures may be used to create magnetic conductors that can be used as ground planes for dipole and loop-like antennas without annihilating the radiation as electrically conducting ground planes would do. An EBG ground plane may be created by placing a Frequency
40 CFR 429.120 - Applicability; description of the sawmills and planing mills subcategory.
2010-07-01
... sawmills and planing mills subcategory. 429.120 Section 429.120 Protection of Environment ENVIRONMENTAL... CATEGORY Sawmills and Planing Mills Subcategory § 429.120 Applicability; description of the sawmills and planing mills subcategory. This subpart applies to discharges to waters of the United States and to the...
47 CFR 73.160 - Vertical plane radiation characteristics, f(θ).
2010-10-01
... 47 Telecommunication 4 2010-10-01 2010-10-01 false Vertical plane radiation characteristics, f(Î... SERVICES RADIO BROADCAST SERVICES AM Broadcast Stations § 73.160 Vertical plane radiation characteristics, f(θ). (a) The vertical plane radiation characteristics show the relative field being radiated at a...
Graphical Representation of Complex Solutions of the Quadratic Equation in the "xy" Plane
McDonald, Todd
2006-01-01
This paper presents a visual representation of complex solutions of quadratic equations in the xy plane. Rather than moving to the complex plane, students are able to experience a geometric interpretation of the solutions in the xy plane. I am also working on these types of representations with higher order polynomials with some success.
The elliptic sine-Gordon equation in a half plane
International Nuclear Information System (INIS)
Pelloni, B; Pinotsis, D A
2010-01-01
We consider boundary value problems for the elliptic sine-Gordon equation posed in the half plane y > 0. This problem was considered in Gutshabash and Lipovskii (1994 J. Math. Sci. 68 197–201) using the classical inverse scattering transform approach. Given the limitations of this approach, the results obtained rely on a nonlinear constraint on the spectral data derived heuristically by analogy with the linearized case. We revisit the analysis of such problems using a recent generalization of the inverse scattering transform known as the Fokas method, and show that the nonlinear constraint of Gutshabash and Lipovskii (1994 J. Math. Sci. 68 197–201) is a consequence of the so-called global relation. We also show that this relation implies a stronger constraint on the spectral data, and in particular that no choice of boundary conditions can be associated with a decaying (possibly mod 2π) solution analogous to the pure soliton solutions of the usual, time-dependent sine-Gordon equation. We also briefly indicate how, in contrast to the evolutionary case, the elliptic sine-Gordon equation posed in the half plane does not admit linearisable boundary conditions
Representation of subharmonic functions in a half-plane
International Nuclear Information System (INIS)
Malyutin, K G; Sadik, N
2007-01-01
The theory of subharmonic functions of finite order is based to a considerable extent on integral formulae. In the present paper representations are obtained for subharmonic functions in the upper half-plane with more general growth γ(r) than finite order. The main result can be stated as follows. Let γ(r) be a growth function such that either lnγ(r) is a convex function of ln r or the lower order of γ(r) is infinite. Then for each proper subharmonic function v of growth γ(r) there exist an unbounded set R of positive numbers and a family (u R :R element of R) of proper subharmonic functions in the upper half-plane C + such that 1) the full measures of the u R in the discs |z|≤R are equal to the full measure of the function v-u R →0 uniformly on compact subsets of C + as R→∞, R element of R; 3) the function family {u R :R element of R} satisfies the growth constraints uniformly in R, that is, T(r,u R )≤Aγ(Br)/r, where A and B are constants and T(r, · ) is the growth characteristic. Bibliography: 16 titles.
VERIFICATION OF THE SENTINEL-4 FOCAL PLANE SUBSYSTEM
Directory of Open Access Journals (Sweden)
C. Williges
2017-05-01
Full Text Available The Sentinel-4 payload is a multi-spectral camera system which is designed to monitor atmospheric conditions over Europe. The German Aerospace Center (DLR in Berlin, Germany conducted the verification campaign of the Focal Plane Subsystem (FPS on behalf of Airbus Defense and Space GmbH, Ottobrunn, Germany. The FPS consists, inter alia, of two Focal Plane Assemblies (FPAs, one for the UV-VIS spectral range (305 nm … 500 nm, the second for NIR (750 nm … 775 nm. In this publication, we will present in detail the opto-mechanical laboratory set-up of the verification campaign of the Sentinel-4 Qualification Model (QM which will also be used for the upcoming Flight Model (FM verification. The test campaign consists mainly of radiometric tests performed with an integrating sphere as homogenous light source. The FPAs have mainly to be operated at 215 K ± 5 K, making it necessary to exploit a thermal vacuum chamber (TVC for the test accomplishment. This publication focuses on the challenge to remotely illuminate both Sentinel-4 detectors as well as a reference detector homogeneously over a distance of approximately 1 m from outside the TVC. Furthermore selected test analyses and results will be presented, showing that the Sentinel-4 FPS meets specifications.
Erector spinae plane block for radical mastectomy: A new indication?
Veiga, M; Costa, D; Brazão, I
2018-02-01
The erector spinae plane block is a technique recently described by Forero et al. in September 2016. It has applications in the control of chronic pain with neuropathic component of the chest wall, and for pain control in thoracoscopic surgery. In this article, we describe the use of this technique as part of a multimodal analgesic approach in a 40-year-old woman, who underwent radical mastectomy due to breast cancer. By performing this block before anesthetic induction, we have achieved an opioid sparing effect, avoiding a possible immunomodulatory effect, although not yet proven in humans. During hospitalization, the patient reported no pain (0/10 in numeric scale), without resorting to rescue analgesia. The easy, fast and safe execution of erector spinae plane block makes it a promising technique in the context of surgical pain during radical mastectomy. Copyright © 2017 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.
Research concerning the balancing of a plane mechanism
Bădoiu, D.; Petrescu, M. G.; Antonescu, N. N.; Toma, G.
2018-01-01
By statically balancing of the plane mechanisms and especially those functioning at high speeds is being pursued the decrease of the value of the resultant force of all inertia forces that work on the component elements, thus obtaining a significant decrease in vibrations and shocks during the functioning. On the other hand, the existence of balancing masses which ensure the balancing of the mechanism leads to increased gauge and its mass. In this paper are presented some possibilities of statically balancing a plane mechanism which is composed of three independent contours. First is analyzed the case when the mechanism is totally balanced. Then a solution is proposed for a partial balancing of the mechanism based on the balancing of the first harmonic of the inertia force developed in a piston of the mechanism. Finally, are presented some simulation results concerning the variation of the value of the resultant inertia force during a cinematic cycle when the mechanism is unbalanced and when it is partially balanced. Also, it is analyzed the variation of the motor moment when the mechanism is unbalanced and when is totally and partially balanced.
Adolescent idiopathic scoliosis: sagital plane and low density pedicle screws
Directory of Open Access Journals (Sweden)
Rodrigo Augusto do Amaral
2014-03-01
Full Text Available OBJECTIVE: To examine the sagittal curves of patients treated with CD instrumentation using exclusively pedicle screws. METHODS: Image analysis of medical records of 27 patients (26 M and 1 F with a minimum follow-up of 6 months, who underwent surgical treatment in our service between January 2005 and December 2010. The curves were evaluated on coronal and sagittal planes, taking into account the potential correction of the technique. RESULTS: In the coronal plan the following curves were evaluated: proximal thoracic (TPx, main thoracic (TPp, and thoracolumbar; lumbar (TL, L, and the average flexibility was 52%, 52%, and 92% and the capacity of correction was 51%, 72%, and 64%, respectively. In the sagittal plane there was a mean increase in thoracic kyphosis (CT of 41% and an average reduction of lumbar lordosis (LL of 17%. Correlation analysis between variables showed Pearson coefficient of correlation of 0.053 and analysis of dispersion of R2 = <0.001. CONCLUSION: The method has shown satisfactory results with maintenance of kyphosis correction in patients with normal and hyper kyphotic deformities.
Distance of the image plane from metal surfaces
International Nuclear Information System (INIS)
Smith, N.V.; Chen, C.T.; Weinert, M.
1989-01-01
The data base of surface-state energies on the metals Cu, Ag, Au, Ni, Pd, and Pt is assembled and, with the aid of a simple model, is used to estimate the distance of the image plane and its trends from surface to surface and metal to metal. The model combines a nearly-free-electron representation of the crystal with a Jones-Jennings-Jepsen ansatz for the saturated image barrier. The projected bulk-band gaps are taken from published determinations. Constraints are placed on the surface barrier parameters by appeal to the results of self-consistent first-principles slab calculations. The general experimental trend observed is for the image-plane distance z 0 to decrease in the sequence (111) to (001) to (110), in the same sense but not as rapidly as z J , the distance of the effective jellium edge. This trend is rationalized using a simple model of the tail of the surface charge density. Typical values for z 0 -z J fall in the range -0.2 to +0.5 a.u., with the larger values occurring for the 3d metals Cu and Ni
Plane boundary effects on characteristics of propeller jets
Wei, Maoxing; Chiew, Yee-Meng; Hsieh, Shih-Chun
2017-10-01
The flow properties of a propeller jet in the presence of a plane bed boundary were investigated using the particle image velocimetry technique. Three clearance heights, Z b = 2 D p, D p, and 0.5 D p, where D p = propeller diameter, were used to examine boundary effects on the development of the jet. In each case, the mean flow properties and turbulence characteristics were measured in a larger field of view than those used in past studies. Both the streamwise and transverse flow fields were measured to obtain the three-dimensional characteristics of the propeller jet. Similar to a confined offset jet, the propeller jet also exhibits a wall attachment behavior when it is placed near a plane boundary. As a result, in contrast to its unconfined counterpart, the confined propeller jet features three regions, namely the free jet, impingement and wall jet regions. The study shows that the extent of each region varies under different clearance heights. The development of the mean flow and turbulence characteristics associated with varying clearance heights are compared to illustrate boundary effects in these regions. In the impingement region, the measured transverse flow fields provide new insights on the lateral motions induced by the impingement of the swirling jet. In the wall jet region, observations reveal that the jet behaves like a typical three-dimensional wall jet and its axial velocity profiles show good agreement with the classical wall jet similarity function.
The confocal plane grating spectrometer at BESSY II
International Nuclear Information System (INIS)
Könnecke, R.; Follath, R.; Pontius, N.; Schlappa, J.; Eggenstein, F.; Zeschke, T.; Bischoff, P.; Schmidt, J.-S.; Noll, T.
2013-01-01
Highlights: ► At the electron storage ring BESSY II a confocal plane grating RIXS endstation with a spot size of 4 μm × 1 μm is presently being installed. ► A resolving power above 10,000 is expected for low energy excitations below 500 eV. ► The sample will be excited with a photon flux up to 10 15 photons/(s 300 mA 0.1%bandwidth). ► Sample environments for solid, gaseous and liquid samples will be provided. ► A fast detecting system is being set up for future pump-probe experiments. -- Abstract: At BESSY II a confocal plane grating spectrometer for resonant inelastic X-ray scattering (RIXS) is currently under commissioning. The new endstation operates with a source size of 4 × 1 μm 2 provided by its dedicated beamline. The RIXS-spectrometer covers an energy range from 50 eV to 1000 eV, providing a resolving power E/ΔE of 5000–15,000. The beamline allows full polarization control and gives a photon flux of up to 7 × 10 14 photons/s/0.1 A/0.1%bandwidth by offering a resolving power E/ΔE of 4000–12,000
Nonlinear stability, bifurcation and resonance in granular plane Couette flow
Shukla, Priyanka; Alam, Meheboob
2010-11-01
A weakly nonlinear stability theory is developed to understand the effect of nonlinearities on various linear instability modes as well as to unveil the underlying bifurcation scenario in a two-dimensional granular plane Couette flow. The relevant order parameter equation, the Landau-Stuart equation, for the most unstable two-dimensional disturbance has been derived using the amplitude expansion method of our previous work on the shear-banding instability.ootnotetextShukla and Alam, Phys. Rev. Lett. 103, 068001 (2009). Shukla and Alam, J. Fluid Mech. (2010, accepted). Two types of bifurcations, Hopf and pitchfork, that result from travelling and stationary linear instabilities, respectively, are analysed using the first Landau coefficient. It is shown that the subcritical instability can appear in the linearly stable regime. The present bifurcation theory shows that the flow is subcritically unstable to disturbances of long wave-lengths (kx˜0) in the dilute limit, and both the supercritical and subcritical states are possible at moderate densities for the dominant stationary and traveling instabilities for which kx=O(1). We show that the granular plane Couette flow is prone to a plethora of resonances.ootnotetextShukla and Alam, J. Fluid Mech. (submitted, 2010)
High operating temperature interband cascade focal plane arrays
Energy Technology Data Exchange (ETDEWEB)
Tian, Z.-B.; Godoy, S. E.; Kim, H. S.; Schuler-Sandy, T.; Montoya, J. A.; Krishna, S. [Center for High Technology Materials, Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, New Mexico 87106 (United States)
2014-08-04
In this paper, we report the initial demonstration of mid-infrared interband cascade (IC) photodetector focal plane arrays with multiple-stage/junction design. The merits of IC photodetectors include low noise and efficient photocarrier extraction, even for zero-bias operation. By adopting enhanced electron barrier design and a total absorber thickness of 0.7 μm, the 5-stage IC detectors show very low dark current (1.10 × 10{sup −7} A/cm{sup 2} at −5 mV and 150 K). Even with un-optimized fabrication and standard commercial (mis-matched) read-out circuit technology, infrared images are obtained by the 320 × 256 IC focal plane array up to 180 K with f/2.3 optics. The minimum noise equivalent temperature difference of 28 mK is obtained at 120 K. These initial results indicate great potential of IC photodetectors, particularly for high operating temperature applications.
High operating temperature interband cascade focal plane arrays
International Nuclear Information System (INIS)
Tian, Z.-B.; Godoy, S. E.; Kim, H. S.; Schuler-Sandy, T.; Montoya, J. A.; Krishna, S.
2014-01-01
In this paper, we report the initial demonstration of mid-infrared interband cascade (IC) photodetector focal plane arrays with multiple-stage/junction design. The merits of IC photodetectors include low noise and efficient photocarrier extraction, even for zero-bias operation. By adopting enhanced electron barrier design and a total absorber thickness of 0.7 μm, the 5-stage IC detectors show very low dark current (1.10 × 10 −7 A/cm 2 at −5 mV and 150 K). Even with un-optimized fabrication and standard commercial (mis-matched) read-out circuit technology, infrared images are obtained by the 320 × 256 IC focal plane array up to 180 K with f/2.3 optics. The minimum noise equivalent temperature difference of 28 mK is obtained at 120 K. These initial results indicate great potential of IC photodetectors, particularly for high operating temperature applications
A novel in-plane mode rotary ultrasonic motor
Directory of Open Access Journals (Sweden)
Lu Xiaolong
2014-04-01
Full Text Available Ultrasonic motors have the merits of high ratio of torque to volume, high positioning precision, intrinsic holding torque, etc., compared to the conventional electromagnetic motors. There have been several potential applications for this type of motor in aerospace exploration, but bearings and bonding mechanism of the piezoelectric ring in the motors limit the performance of them in the space operation conditions. It is known that the Langevin type transducer has excellent energy efficiency and reliability. Hence using the Langevin type transducer in ultrasonic motors may improve the reliability of piezoelectric motors for space applications. In this study, a novel in-plane mode rotary ultrasonic motor is designed, fabricated, and characterized. The proposed motor operates in in-plane vibration mode which is excited by four Langevin-type bending vibrators separately placed around a ring-shaped stator. Two tapered rotors are assembled to the inner ring of the stator and clamped together by a screw nut. In order to make the motor more stable and convenient to fix, a thin cylindrical support is placed under the stator ring. Due to its no-bearing structure and Langevin transducer excitation, the prototype ultrasonic motor may operate well in aeronautic and astronautic environments.
In-plane optical response in underdoped YBCO
Kakeshita, Teruhisa; Masui, Takahiko; Tajima, Setsuko
2005-03-01
The recent STM experiments demonstrated that the electronic state in CuO2 plane is inhomogeneous [1], which becomes conspicuous in the underdoped regime. In such an inhomogeneous state, it is not obvious whether a superfluid density is correctly estimated by a conventional way. We investigated the in-plane optical response for underdoped YBCO crystal to discuss the relation between inhomogeneity and superfluid density in the pseudo-gapped state. The a-axis optical spectrum shows a larger residual conductivity than that for the optimum doping. The superfluid density estimated from our optical spectrum at the lowest temperature is substantially smaller than that determined by μSR. We discuss this strongly suppressed superfluid density and the large residual conductivity in terms of the inhomogeneity in real- and k-space. This work was supported by the New Energy and Industrial Technology Development Organization(NEDO) through ISTEC as the Collaborative Research and Development of Fundamental Technologies for Superconductivity Applications. [1]K.M.Lang et al., Nature 415, 412 (2002). *present address: Dept. of Physics, Osaka University, Machikaneyama 1-1, Toyonaka, Osaka 560-0043, Japan
Measure Guideline: Guidance on Taped Insulating Sheathing Drainage Planes
Energy Technology Data Exchange (ETDEWEB)
Grin, A.; Lstiburek, J.
2014-09-01
This guide provides information and recommendations to the following groups: insulation contractors; general contractors; builders; home remodelers; mechanical contractors; and homeowners, as a guide to the work that needs to be done. The order of work completed during home construction and retrofit improvements is important. Health and safety issues must be addressed first and are more important than durability issues. And durability issues are more important than saving energy. Not all techniques can apply to all houses. Special conditions will require special action. Some builders or homeowners will wish to do more than the important but basic retrofit strategies outlined by this guide. The following are best practice and product recommendations from the interviewed contractors and homebuilders who collectively have a vast amount of experience. Three significant items were discussed with the group which are required to make taped insulating sheathing a simple, long term, and durable drainage plane: 1. Horizontal joints should be limited or eliminated wherever possible; 2. Where a horizontal joint exists use superior materials; 3. Frequent installation inspection and regular trade training are required to maintain proper installation. Section 5 of this measure guideline contains the detailed construction procedure for the three recommended methods to effectively seal the joints in exterior insulating sheathing to create a simple, long term, and durable drainage plane.
Verification of the Sentinel-4 focal plane subsystem
Williges, Christian; Uhlig, Mathias; Hilbert, Stefan; Rossmann, Hannes; Buchwinkler, Kevin; Babben, Steffen; Sebastian, Ilse; Hohn, Rüdiger; Reulke, Ralf
2017-09-01
The Sentinel-4 payload is a multi-spectral camera system, designed to monitor atmospheric conditions over Europe from a geostationary orbit. The German Aerospace Center, DLR Berlin, conducted the verification campaign of the Focal Plane Subsystem (FPS) during the second half of 2016. The FPS consists, of two Focal Plane Assemblies (FPAs), two Front End Electronics (FEEs), one Front End Support Electronic (FSE) and one Instrument Control Unit (ICU). The FPAs are designed for two spectral ranges: UV-VIS (305 nm - 500 nm) and NIR (750 nm - 775 nm). In this publication, we will present in detail the set-up of the verification campaign of the Sentinel-4 Qualification Model (QM). This set up will also be used for the upcoming Flight Model (FM) verification, planned for early 2018. The FPAs have to be operated at 215 K +/- 5 K, making it necessary to exploit a thermal vacuum chamber (TVC) for the test accomplishment. The test campaign consists mainly of radiometric tests. This publication focuses on the challenge to remotely illuminate both Sentinel-4 detectors as well as a reference detector homogeneously over a distance of approximately 1 m from outside the TVC. Selected test analyses and results will be presented.
Photoelectron wave function in photoionization: plane wave or Coulomb wave?
Gozem, Samer; Gunina, Anastasia O; Ichino, Takatoshi; Osborn, David L; Stanton, John F; Krylov, Anna I
2015-11-19
The calculation of absolute total cross sections requires accurate wave functions of the photoelectron and of the initial and final states of the system. The essential information contained in the latter two can be condensed into a Dyson orbital. We employ correlated Dyson orbitals and test approximate treatments of the photoelectron wave function, that is, plane and Coulomb waves, by comparing computed and experimental photoionization and photodetachment spectra. We find that in anions, a plane wave treatment of the photoelectron provides a good description of photodetachment spectra. For photoionization of neutral atoms or molecules with one heavy atom, the photoelectron wave function must be treated as a Coulomb wave to account for the interaction of the photoelectron with the +1 charge of the ionized core. For larger molecules, the best agreement with experiment is often achieved by using a Coulomb wave with a partial (effective) charge smaller than unity. This likely derives from the fact that the effective charge at the centroid of the Dyson orbital, which serves as the origin of the spherical wave expansion, is smaller than the total charge of a polyatomic cation. The results suggest that accurate molecular photoionization cross sections can be computed with a modified central potential model that accounts for the nonspherical charge distribution of the core by adjusting the charge in the center of the expansion.
Mesiodistal tooth angulation to segmental occlusal plane in panoramic radiography
International Nuclear Information System (INIS)
Kim, Jae Duk; Kim, Jin Soo; You, Choong Hyun
2005-01-01
To evaluate the stability of the segmental occlusal plane and anatomical line as the reference line for measuring the mesiodistal tooth angulation in panoramic radiography and to determine the mean angle and the range of the mesiodistal tooth angulation in Korean population with normal occlusions. Twenty nine subjects (15 men, 14 women) with normal occlusion were selected. A total of 29 panoramic radiograms were taken at normal head position and then 10 images of 5 subjects selected were repeatedly taken with repositioning 2 times at each of the head down (V-shaped occlusion) and up (horizontal occulsion) for evaluation of stability of adopted reference lines by using PM2002CC (Planmeca, Finland). The images were traced with adoption of two test reference lines and the long axes of the teeth. The mesial angles formed by each reference line and the long axes of the teeth were measured and analyzed. With anatomical reference line, the mesiodistal tooth angulations of the molars showed the significant difference by over 5 degree between the normal and each changed head position. With segmented occlusal reference line, deviations of mesiodistal tooth angulations by the two changed head positions were less than 1 degree. The means, standard deviations, and maximum and minimum values of mesiodistal tooth angulations to segmental occlusal reference line on panoramic radiography were determined. It would appear that mesiodistal tooth angulations to segmental occlusal plane as reference line in panograms are predictable as standards of normal occlusion and useful for evaluation of tooth arrangement between adjacent teeth.
Mesiodistal tooth angulation to segmental occlusal plane in panoramic radiography
Energy Technology Data Exchange (ETDEWEB)
Kim, Jae Duk; Kim, Jin Soo; You, Choong Hyun [Chosun University College of Medicine, Kwangju (Korea, Republic of)
2005-03-15
To evaluate the stability of the segmental occlusal plane and anatomical line as the reference line for measuring the mesiodistal tooth angulation in panoramic radiography and to determine the mean angle and the range of the mesiodistal tooth angulation in Korean population with normal occlusions. Twenty nine subjects (15 men, 14 women) with normal occlusion were selected. A total of 29 panoramic radiograms were taken at normal head position and then 10 images of 5 subjects selected were repeatedly taken with repositioning 2 times at each of the head down (V-shaped occlusion) and up (horizontal occulsion) for evaluation of stability of adopted reference lines by using PM2002CC (Planmeca, Finland). The images were traced with adoption of two test reference lines and the long axes of the teeth. The mesial angles formed by each reference line and the long axes of the teeth were measured and analyzed. With anatomical reference line, the mesiodistal tooth angulations of the molars showed the significant difference by over 5 degree between the normal and each changed head position. With segmented occlusal reference line, deviations of mesiodistal tooth angulations by the two changed head positions were less than 1 degree. The means, standard deviations, and maximum and minimum values of mesiodistal tooth angulations to segmental occlusal reference line on panoramic radiography were determined. It would appear that mesiodistal tooth angulations to segmental occlusal plane as reference line in panograms are predictable as standards of normal occlusion and useful for evaluation of tooth arrangement between adjacent teeth.
A Tiered Control Plane Model for Service Function Chaining Isolation
Directory of Open Access Journals (Sweden)
Håkon Gunleifsen
2018-06-01
Full Text Available This article presents an architecture for encryption automation in interconnected Network Function Virtualization (NFV domains. Current NFV implementations are designed for deployment within trusted domains, where overlay networks with static trusted links are utilized for enabling network security. Nevertheless, within a Service Function Chain (SFC, Virtual Network Function (VNF flows cannot be isolated and end-to-end encrypted because each VNF requires direct access to the overall SFC data-flow. This restricts both end-users and Service Providers from enabling end-to-end security, and in extended VNF isolation within the SFC data traffic. Encrypting data flows on a per-flow basis results in an extensive amount of secure tunnels, which cannot scale efficiently in manual configurations. Additionally, creating secure data plane tunnels between NFV providers requires secure exchange of key parameters, and the establishment of an east–west control plane protocol. In this article, we present an architecture focusing on these two problems, investigating how overlay networks can be created, isolated, and secured dynamically. Accordingly, we propose an architecture for automated establishment of encrypted tunnels in NFV, which introduces a novel, tiered east–west communication channel between network controllers in a multi-domain environment.
Focal plane based wavefront sensing with random DM probes
Pluzhnik, Eugene; Sirbu, Dan; Belikov, Ruslan; Bendek, Eduardo; Dudinov, Vladimir N.
2017-09-01
An internal coronagraph with an adaptive optical system for wavefront control is being considered for direct imaging of exoplanets with upcoming space missions and concepts, including WFIRST, HabEx, LUVOIR, EXCEDE and ACESat. The main technical challenge associated with direct imaging of exoplanets is to control of both diffracted and scattered light from the star so that even a dim planetary companion can be imaged. For a deformable mirror (DM) to create a dark hole with 10-10 contrast in the image plane, wavefront errors must be accurately measured on the science focal plane detector to ensure a common optical path. We present here a method that uses a set of random phase probes applied to the DM to obtain a high accuracy wavefront estimate even for a dynamically changing optical system. The presented numerical simulations and experimental results show low noise sensitivity, high reliability, and robustness of the proposed approach. The method does not use any additional optics or complex calibration procedures and can be used during the calibration stage of any direct imaging mission. It can also be used in any optical experiment that uses a DM as an active optical element in the layout.
Finite Thin Cover on an Orthotropic Elastic Half Plane
Directory of Open Access Journals (Sweden)
Federico Oyedeji Falope
2016-01-01
Full Text Available The present work deals with the mechanical behaviour of thin films bonded to a homogeneous elastic orthotropic half plane under plain strain condition and infinitesimal strain. Both the film and semi-infinite substrate display linear elastic orthotropic behaviour. By assuming perfect adhesion between film and half plane together with membrane behaviour of the film, the compatibility condition between the coating and substrate leads to a singular integral equation with Cauchy kernel. Such an equation is straightforwardly solved by expanding the unknown interfacial stress in series of Chebyshev polynomials displaying square-root singularity at the film edges. This approach allows handling the singular behaviour of the shear stress and, in turn, reducing the problem to a linear algebraic system of infinite terms. Results are found for two loading cases, with particular reference to concentrated axial forces acting at the edges of the film. The corresponding mode II stress intensity factor has been assessed, thus providing the stress concentrations at both ends of the covering. Possible applications of the results here obtained range from MEMS, NEMS, and solar Silicon cell for energy harvesting to welded joint and building foundation.
Takagi, Shigeru; Sato, Takashi; Watanabe, Satoshi; Tanifuji, Osamu; Mochizuki, Tomoharu; Omori, Go; Endo, Naoto
2017-11-17
Abnormalities of lower extremity alignment (LEA) in recurrent patella dislocation (RPD) have been studied mostly by two-dimensional (2D) procedures leaving three-dimensional (3D) factors unknown. This study aimed to three-dimensionally examine risk factors for RPD in lower extremity alignment under the weight-bearing conditions. The alignment of 21 limbs in 15 RPD subjects was compared to the alignment of 24 limbs of 12 healthy young control subjects by an our previously reported 2D-3D image-matching technique. The sagittal, coronal, and transverse alignment in full extension as well as the torsional position of the femur (anteversion) and tibia (tibial torsion) under weight-bearing standing conditions were assessed by our previously reported 3D technique. The correlations between lower extremity alignment and RPD were assessed using multiple logistic regression analysis. The difference of lower extremity alignment in RPD between under the weight-bearing conditions and under the non-weight-bearing conditions was assessed. In the sagittal and coronal planes, there was no relationship (statistically or by clinically important difference) between lower extremity alignment angle and RPD. However, in the transverse plane, increased external tibial rotation [odds ratio (OR) 1.819; 95% confidence interval (CI) 1.282-2.581], increased femoral anteversion (OR 1.183; 95% CI 1.029-1.360), and increased external tibial torsion (OR 0.880; 95% CI 0.782-0.991) were all correlated with RPD. The tibia was more rotated relative to femur at the knee joint in the RPD group under the weight-bearing conditions compared to under the non-weight-bearing conditions (p alignment parameters in the transverse plane related to the risk of RPD, while in the sagittal and coronal plane alignment parameters did not correlate with RPD. The clinical importance of this study is that the 3D measurements more directly, precisely, and sensitively detect rotational parameters associated with RPD and
NCC-RANSAC: a fast plane extraction method for 3-D range data segmentation.
Qian, Xiangfei; Ye, Cang
2014-12-01
This paper presents a new plane extraction (PE) method based on the random sample consensus (RANSAC) approach. The generic RANSAC-based PE algorithm may over-extract a plane, and it may fail in case of a multistep scene where the RANSAC procedure results in multiple inlier patches that form a slant plane straddling the steps. The CC-RANSAC PE algorithm successfully overcomes the latter limitation if the inlier patches are separate. However, it fails if the inlier patches are connected. A typical scenario is a stairway with a stair wall where the RANSAC plane-fitting procedure results in inliers patches in the tread, riser, and stair wall planes. They connect together and form a plane. The proposed method, called normal-coherence CC-RANSAC (NCC-RANSAC), performs a normal coherence check to all data points of the inlier patches and removes the data points whose normal directions are contradictory to that of the fitted plane. This process results in separate inlier patches, each of which is treated as a candidate plane. A recursive plane clustering process is then executed to grow each of the candidate planes until all planes are extracted in their entireties. The RANSAC plane-fitting and the recursive plane clustering processes are repeated until no more planes are found. A probabilistic model is introduced to predict the success probability of the NCC-RANSAC algorithm and validated with real data of a 3-D time-of-flight camera-SwissRanger SR4000. Experimental results demonstrate that the proposed method extracts more accurate planes with less computational time than the existing RANSAC-based methods.
International Nuclear Information System (INIS)
Imafuku, Muneyuki; Suzuki, Hiroshi; Sueyoshi, Kazuyuki; Akita, Koichi; Ohya, Shin-ichi
2008-01-01
Generalized formula of the x-ray stress analysis for a single crystal with unknown stress-free lattice parameter was proposed. This method enables us to evaluate the plane stress states with any combination of diffraction planes. We can choose and combine the appropriate x-ray sources and diffraction plane families, depending on the sample orientation and the apparatus, whenever diffraction condition is satisfied. The analysis of plane stress distributions in an iron single crystal was demonstrated combining with the diffraction data for Fe{211} and Fe{310} plane families
Improvement of image quality of holographic projection on tilted plane using iterative algorithm
Pang, Hui; Cao, Axiu; Wang, Jiazhou; Zhang, Man; Deng, Qiling
2017-12-01
Holographic image projection on tilted plane has an important application prospect. In this paper, we propose a method to compute the phase-only hologram that can reconstruct a clear image on tilted plane. By adding a constant phase to the target image of the inclined plane, the corresponding light field distribution on the plane that is parallel to the hologram plane is derived through the titled diffraction calculation. Then the phase distribution of the hologram is obtained by the iterative algorithm with amplitude and phase constrain. Simulation and optical experiment are performed to show the effectiveness of the proposed method.
International Nuclear Information System (INIS)
Savel'ev, Sergey; Yampol'skii, Valery; Rakhmanov, Alexander; Nori, Franco
2005-01-01
We show that a moving Josephson vortex in spatially modulated layered superconductors generates out-of-plane THz radiation. Remarkably, the magnetic and in-plane electric fields radiated are of the same order, which is very unusual for any good-conducting medium. Therefore, the out-of-plane radiation can be emitted to the vacuum without the standard impedance mismatch problem. Thus, the proposed tunable THz emitter for out-of-plane radiation can be more efficient than the standard one which radiates only along the ab-plane
The study of practices in planed diagnostic medical exposure
International Nuclear Information System (INIS)
Popescu, Irina-Anca; Perju, Nicoleta Ana-Maria; Cobzeanu, Camelia
2011-01-01
The exposure of population to ionizing radiations in medical diagnostic purposes represents a planed exposure procedure, medically justified, having a direct impact on patient health state. A justification of exposure, with a result that can confirm a clinical diagnostic, implies further important steps in treatment decisions. Optimization in patients radiological protection is the result of observing the reference levels recommendations, which maintains a reasonable individual exposure to ionizing radiation in medical purpose. In this paper we investigated the justification of 4189 exposures of patients who underwent planed diagnostic medical investigation over 36 months in a radiological unit. The most frequent investigation concerned the spinal column in 38.3% of total exposures-mainly at lumbar level (63.0% and 24.1%, respectively of total number of exposures), followed by limb bones (20.6%) and thorax (26.9%). Justification of practices included: rheumatic pains in 45.8% of exposures followed by traumatic injuries (20.6%), pleural and pulmonary pathology (19.3%), malignant processes (12.3%), ear-nose-throat investigations (1.1%) and car accidents (0.9%). The females over 40 years old were the group with the highest number of medical exposures, with 54.5% of total practices. This study revealed that the number of medical exposures justification is almost equal with non-justified examinations, confirming a not so good correlation between clinical diagnostic and the required radiological investigation. The percentages of justified versus non-justified practices indicated by specialist physicians and general practitioners were slightly equal - 59.3% vs. 40.7%, 56.9% vs. 43.1%, respectively. The analysis of data concluded that either specialist/general physicians must evaluate more rigorously the patients and all clinical signs in order to reduce as reasonable as possible the non-justified medical exposures to ionizing radiations, and thus to avoid financial and
Performance of a PV module augmented by a plane reflector
Energy Technology Data Exchange (ETDEWEB)
Ahmad, G. E; Hussein, H. M. S; Mohamad, M. A [Dokki, Giza (Egypt)
2000-07-01
This paper presents a comparative experimental study on the performance of a PV module augmented by a south facing titled plane reflector and another identical one without reflector. The tilt angles of the two PV modules and reflector overhang are selected to be according to a previous theoretical study by the authors. The reflector tilt angle has been changed once a month so that the reflected beams from the plane reflector cover the total surface area of the PV module all days of every month during the high solar radiation period (i.e. three hours before and after solar noon). The study has been carried out on the two PV modules for a complete year under the actual atmospheric conditions of Cairo, Egypt. The measuring system used in the study comprises a data acquisition system, a computer, an electronic load and weather station. The experimental results indicate that the plane reflector enhances the yearly output energy of the PV module y about 22%. [Spanish] Este articulo presenta un estudio comparativo experimental sobre el rendimiento de un modulo de PV aumentado por un reflector plano inclinado mirando hacia el sur y otro identico sin reflector. Los angulos de inclinacion de los dos modulos y el reflector sobresaliente se seleccionan para que esten de acuerdo con un estudio teorico previo hecho por los autores. El angulo de inclinacion del reflector se cambio una vez al mes de manera que los rayos reflejados por el reflector plano cubrieran el area total de la superficie del modulo de PV todos los dias de cada mes durante el periodo de radiacion alto (o sea tres horas antes y despues del medio dia solar). El estudio ha sido llevado a cabo en dos modulos de PV durante un ano completo bajo condiciones atmosfericas reales de El Cairo, Egipto. El sistema de medicion usado en el estudio comprende un sistema de adquisicion de datos, una computadora, una memoria electronica y una estacion climatologica. Los resultados experimentales indican que el reflector plano
Electrical impedance along connective tissue planes associated with acupuncture meridians
Directory of Open Access Journals (Sweden)
Hammerschlag Richard
2005-05-01
Full Text Available Abstract Background Acupuncture points and meridians are commonly believed to possess unique electrical properties. The experimental support for this claim is limited given the technical and methodological shortcomings of prior studies. Recent studies indicate a correspondence between acupuncture meridians and connective tissue planes. We hypothesized that segments of acupuncture meridians that are associated with loose connective tissue planes (between muscles or between muscle and bone visible by ultrasound have greater electrical conductance (less electrical impedance than non-meridian, parallel control segments. Methods We used a four-electrode method to measure the electrical impedance along segments of the Pericardium and Spleen meridians and corresponding parallel control segments in 23 human subjects. Meridian segments were determined by palpation and proportional measurements. Connective tissue planes underlying those segments were imaged with an ultrasound scanner. Along each meridian segment, four gold-plated needles were inserted along a straight line and used as electrodes. A parallel series of four control needles were placed 0.8 cm medial to the meridian needles. For each set of four needles, a 3.3 kHz alternating (AC constant amplitude current was introduced at three different amplitudes (20, 40, and 80 μAmps to the outer two needles, while the voltage was measured between the inner two needles. Tissue impedance between the two inner needles was calculated based on Ohm's law (ratio of voltage to current intensity. Results At the Pericardium location, mean tissue impedance was significantly lower at meridian segments (70.4 ± 5.7 Ω compared with control segments (75.0 ± 5.9 Ω (p = 0.0003. At the Spleen location, mean impedance for meridian (67.8 ± 6.8 Ω and control segments (68.5 ± 7.5 Ω were not significantly different (p = 0.70. Conclusion Tissue impedance was on average lower along the Pericardium meridian, but not
A novel fabrication process for out-of-plane microneedle sheets of biocompatible polymer
Han, Manhee; Hyun, Dong-Hun; Park, Hyoun-Hyang; Lee, Seung S.; Kim, Chang-Hyeon; Kim, Changgyou
2007-06-01
This paper presents a novel process for fabricating out-of-plane microneedle sheets of biocompatible polymer using in-plane microneedles. This process comprises four steps: (1) fabrication of in-plane microneedles using inclined UV lithography and electroforming, (2) conversion of the in-plane microneedles to an out-of-plane microneedle array, (3) fabrication of a negative PDMS mold and (4) fabrication of out-of-plane microneedle sheets of biocompatible polymer by hot embossing. The in-plane microneedles are fabricated with a sharp tip for low insertion forces and are made long to ensure sufficient penetration depth. The in-plane microneedles are converted into an out-of-plane microneedle array to increase the needle density. The negative mold is fabricated for mass-production using a polymer molding technique. The final out-of-plane microneedle sheets are produced using polycarbonate for biocompatibility by employing the hot embossing process. The height of the fabricated needles ranges from 500 to 1500 µm, and the distance between the needles is 500 to 2000 µm. The radii of curvature are approximately 2 µm, while the tip angles are in the range of 39-56°. Most of the geometrical characteristics of the out-of-plane microneedles can be freely controlled for real life applications such as drug delivery, cosmetic delivery and mesotherapy. Since it is also possible to mass-produce the microneedles, this novel process holds sufficient potential for applications in industrial fields.
International Nuclear Information System (INIS)
Moon, Hee Jung; Kwak, Jin Young; Kim, Eun Kyung
2012-01-01
To evaluate the diagnostic performance of elastography for thyroid nodules on the transverse and longitudinal planes. Gray scale ultrasonography (US), elastography on trans- verse and longitudinal planes, and fine needle aspiration biopsy for 78 thyroid nodules (malignant: 34 cases, benign: 44 cases) were performed. According to the Asteria criteria of elastography, scores 1 and 2 were classified as probably benign and scores 3 and 4 were classified as suspicious. Strain ratios on transverse and longitudinal planes were measured. Sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and Az value (under the receiver operating characteristics curve) of elastography on transverse and longitudinal planes were calculated and compared. Scores 3 and 4 were more frequently seen in malignant nodules on the longitudinal plane (p value = 0.007), but not significantly seen on the transverse plane (p value = 0.160). Sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and the Az value of elastography on the longitudinal plane were higher than those on the transverse plane, although Az values on the transverse and longtudinal planes were not statistically significant. Diagnostic performance of thyroid elastography, especially sensitivity, were higher on the longitudinal plane than the transverse plane
Comparing trapezius muscle activity in the different planes of shoulder elevation.
Ishigaki, Tomonobu; Ishida, Tomoya; Samukawa, Mina; Saito, Hiroshi; Hirokawa, Motoki; Ezawa, Yuya; Sugawara, Makoto; Tohyama, Harukazu; Yamanaka, Masanori
2015-05-01
[Purpose] The purpose of this study was to compare the upper, middle, and lower trapezius muscles' activity in the different planes of shoulder elevation. [Subjects] Twenty male subjects volunteered for this study. [Methods] Surface electromyographic (EMG) activity for each of the three regions of the trapezius muscles in the three different planes of elevation were collected while the participants maintained 30, 60, and 90 degrees of elevation in each plane. The EMG data were normalized with maximum voluntary isometric contraction (%MVIC), and compared among the planes at each angle of elevation. [Results] There were significantly different muscle activities among the elevation planes at each angle. [Conclusion] This study found that the three regions of the trapezius muscles changed their activity depending on the planes of shoulder elevation. These changes in the trapezius muscles could induce appropriate scapular motion to face the glenoid cavity in the correct directions in different planes of shoulder elevation.
Identifying logical planes formed of compute nodes of a subcommunicator in a parallel computer
Davis, Kristan D.; Faraj, Daniel A.
2016-03-01
In a parallel computer, a plurality of logical planes formed of compute nodes of a subcommunicator may be identified by: for each compute node of the subcommunicator and for a number of dimensions beginning with a first dimension: establishing, by a plane building node, in a positive direction of the first dimension, all logical planes that include the plane building node and compute nodes of the subcommunicator in a positive direction of a second dimension, where the second dimension is orthogonal to the first dimension; and establishing, by the plane building node, in a negative direction of the first dimension, all logical planes that include the plane building node and compute nodes of the subcommunicator in the positive direction of the second dimension.
Cui, Chaojie; Hu, Weijin; Yan, Xingxu; Addiego, Christopher; Gao, Wenpei; Wang, Yao; Wang, Zhe; Li, Linze; Cheng, Yingchun; Li, Peng; Zhang, Xixiang; Alshareef, Husam N.; Wu, Tao; Zhu, Wenguang; Pan, Xiaoqing; Li, Lain-Jong
2018-01-01
Enriching the functionality of ferroelectric materials with visible-light sensitivity and multiaxial switching capability would open up new opportunities for their applications in advanced information storage with diverse signal manipulation functions. We report experimental observations of robust intra-layer ferroelectricity in two-dimensional (2D) van der Waals layered -In2Se3 ultrathin flakes at room temperature. Distinct from other 2D and conventional ferroelectrics, In2Se3 exhibits intrinsically intercorrelated out-of-plane and in-plane polarization, where the reversal of the out-of-plane polarization by a vertical electric field also induces the rotation of the in-plane polarization. Based on the in-plane switchable diode effect and the narrow bandgap (~1.3 eV) of ferroelectric In2Se3, a prototypical non-volatile memory device, which can be manipulated both by electric field and visible light illumination, is demonstrated for advancing data storage technologies.
Cui, Chaojie; Hu, Wei-Jin; Yan, Xingxu; Addiego, Christopher; Gao, Wenpei; Wang, Yao; Wang, Zhe; Li, Linze; Cheng, Yingchun; Li, Peng; Zhang, Xixiang; Alshareef, Husam N; Wu, Tom; Zhu, Wenguang; Pan, Xiaoqing; Li, Lain-Jong
2018-02-14
Enriching the functionality of ferroelectric materials with visible-light sensitivity and multiaxial switching capability would open up new opportunities for their applications in advanced information storage with diverse signal manipulation functions. We report experimental observations of robust intralayer ferroelectricity in two-dimensional (2D) van der Waals layered α-In 2 Se 3 ultrathin flakes at room temperature. Distinct from other 2D and conventional ferroelectrics, In 2 Se 3 exhibits intrinsically intercorrelated out-of-plane and in-plane polarization, where the reversal of the out-of-plane polarization by a vertical electric field also induces the rotation of the in-plane polarization. On the basis of the in-plane switchable diode effect and the narrow bandgap (∼1.3 eV) of ferroelectric In 2 Se 3 , a prototypical nonvolatile memory device, which can be manipulated both by electric field and visible light illumination, is demonstrated for advancing data storage technologies.
Cui, Chaojie
2018-01-30
Enriching the functionality of ferroelectric materials with visible-light sensitivity and multiaxial switching capability would open up new opportunities for their applications in advanced information storage with diverse signal manipulation functions. We report experimental observations of robust intra-layer ferroelectricity in two-dimensional (2D) van der Waals layered -In2Se3 ultrathin flakes at room temperature. Distinct from other 2D and conventional ferroelectrics, In2Se3 exhibits intrinsically intercorrelated out-of-plane and in-plane polarization, where the reversal of the out-of-plane polarization by a vertical electric field also induces the rotation of the in-plane polarization. Based on the in-plane switchable diode effect and the narrow bandgap (~1.3 eV) of ferroelectric In2Se3, a prototypical non-volatile memory device, which can be manipulated both by electric field and visible light illumination, is demonstrated for advancing data storage technologies.
Numerical and experimental study of two turbulent opposed plane jets
Energy Technology Data Exchange (ETDEWEB)
Besbes, Sonia; Mhiri, Hatem [Laboratoire de Mecanique des Fluides et Thermique, Ecole Nationale d' Ingenieurs de Monastir, Route de Ouardanine, Monastir (Tunisia); Le Palec, Georges; Bournot, Philippe [Institut de Mecanique de Marseille, UNIMECA, Technopole de Chateau-Gombert, 60 rue Joliot-Curie, 13453 Marseille (France)
2003-09-01
The turbulent interaction between two opposed plane jets separated by a distance H is experimentally studied by using a PIV (Particle Image Velocimetry) method and numerically investigated by means of a finite volume code. Two turbulence models have been tested: the standard k-{epsilon} model and a second-order model. The validation of the numerical study was performed by comparing the results with experimental data obtained for the case of two interacting opposed jets at ambient temperature (isothermal case). The effect of the angle of inclination of the jets is studied. Conclusions of the validation are then used to study the interaction between two jets, one being maintained at ambient temperature whereas the other is heated. Results show that the stagnation point moves towards the heated jet. It is shown that the heating induces a stabilizing effect on the flow. (orig.)
Observers in Kerr spacetimes. The ergoregion on the equatorial plane
Energy Technology Data Exchange (ETDEWEB)
Pugliese, D. [Silesian University in Opava, Faculty of Philosophy and Science, Institute of Physics, Opava (Czech Republic); Quevedo, H. [Universita di Roma ' ' La Sapienza' ' , Dipartimento di Fisica, Rome (Italy); Universidad Nacional Autonoma de Mexico, Instituto de Ciencias Nucleares, Mexico, DF (Mexico); Kazakh National University, Department of Theoretical and Nuclear Physics, Almaty (Kazakhstan)
2018-01-15
We perform a detailed analysis of the properties of stationary observers located on the equatorial plane of the ergosphere in a Kerr spacetime, including light-surfaces. This study highlights crucial differences between black hole and the super-spinner sources. In the case of Kerr naked singularities, the results allow us to distinguish between ''weak'' and ''strong'' singularities, corresponding to spin values close to or distant from the limiting case of extreme black holes, respectively. We derive important limiting angular frequencies for naked singularities. We especially study very weak singularities as resulting from the spin variation of black holes. We also explore the main properties of zero angular momentum observers for different classes of black hole and naked singularity spacetimes. (orig.)
Overvoltage protection by point-plane spark gaps
International Nuclear Information System (INIS)
Scarlett, W.R.; Riepe, K.B.
1979-01-01
In electron-beam-controlled discharge CO 2 lasers, such as those used in the Antares and Helios laser-fusion drivers at the Los Alamos Scientific Laboratory (LASL), protection needs to be provided against possible damage due to overvoltage. A passive (self-breakdown) point-plane spark gap has been developed and successfully used in the Helios power amplifiers which operate at voltages up to 300 kV. A gap of similar design is planned for use in the Antares power amplifiers which operate at 550 kV. These gaps must reliably hold off the normal discharge voltage, but break down with short delay if overvoltaged, diverting the discharge energy to a resistor. A prototype of the Antares gap has been built and is undergoing tests. Parameters being investigated include voltage polarity, gap spacing, gas composition, and gas pressure. Results of these measurements and the operational experience of the Helios gaps will be presented
Violin bridge mobility analysis under in-plane excitation.
Zhang, Cheng-Zhong; Zhang, Guang-Ming; Ye, Bang-Yan; Liang, Li-Dong
2013-11-08
The vibration of a violin bridge is a dynamic contact vibration with two interfaces: strings-bridge, and bridge feet-top plate. In this paper, the mobility of an isolated bridge under in-plane excitation is explored using finite element modeling based on the contact vibration model. Numerical results show that the dynamic contact stiffness in the two contact interfaces has a great impact on the bridge mobility. A main resonance peak is observed in the frequency range of 2-3 kHz in the frequency response of the isolated bridge when the contact stiffness is smaller than a critical threshold. The main resonance peak frequency is affected by the contact stiffness as well. In order to verify the numerical findings, a novel experimental system is then designed on the basis of a piezoelectric dynamometer for bridge mobility analysis. Experimental results confirm the impact of the dynamic contact stiffness on the bridge mobility.
Third-generation intelligent IR focal plane arrays
Caulfield, H. John; Jack, Michael D.; Pettijohn, Kevin L.; Schlesselmann, John D.; Norworth, Joe
1998-03-01
SBRC is at the forefront of industry in developing IR focal plane arrays including multi-spectral technology and '3rd generation' functions that mimic the human eye. 3rd generation devices conduct advanced processing on or near the FPA that serve to reduce bandwidth while performing needed functions such as automatic target recognition, uniformity correction and dynamic range enhancement. These devices represent a solution for processing the exorbitantly high bandwidth coming off large area FPAs without sacrificing systems sensitivity. SBRC's two-color approach leverages the company's HgCdTe technology to provide simultaneous multiband coverage, from short through long wave IR, with near theoretical performance. IR systems that are sensitive to different spectral bands achieve enhanced capabilities for target identification and advanced discrimination. This paper will provide a summary of the issues, the technology and the benefits of SBRC's third generation smart and two-color FPAs.
Augmented-plane-wave calculations on small molecules
International Nuclear Information System (INIS)
Serena, P.A.; Baratoff, A.; Soler, J.M.
1993-01-01
We have performed ab initio calculations on a wide range of small molecules, demonstrating the accuracy and flexibility of an alternative method for calculating the electronic structure of molecules, solids, and surfaces. It is based on the local-density approximation (LDA) for exchange and correlation and the nonlinear augmented-plane-wave method. Very accurate atomic forces are obtained directly. This allows for implementation of Car-Parrinello-like techniques to determine simultaneously the self-consistent electron wave functions and the equilibrium atomic positions within an iterative scheme. We find excellent agreement with the best existing LDA-based calculations and remarkable agreement with experiment for the equilibrium geometries, vibrational frequencies, and dipole moments of a wide variety of molecules, including strongly bound homopolar and polar molecules, hydrogen-bound and electron-deficient molecules, and weakly bound alkali and noble-metal dimers, although binding energies are overestimated
Linear augmented plane wave method for self-consistent calculations
International Nuclear Information System (INIS)
Takeda, T.; Kuebler, J.
1979-01-01
O.K. Andersen has recently introduced a linear augmented plane wave method (LAPW) for the calculation of electronic structure that was shown to be computationally fast. A more general formulation of an LAPW method is presented here. It makes use of a freely disposable number of eigenfunctions of the radial Schroedinger equation. These eigenfunctions can be selected in a self-consistent way. The present formulation also results in a computationally fast method. It is shown that Andersen's LAPW is obtained in a special limit from the present formulation. Self-consistent test calculations for copper show the present method to be remarkably accurate. As an application, scalar-relativistic self-consistent calculations are presented for the band structure of FCC lanthanum. (author)
Violin Bridge Mobility Analysis under In-Plane Excitation
Directory of Open Access Journals (Sweden)
Cheng-Zhong Zhang
2013-11-01
Full Text Available The vibration of a violin bridge is a dynamic contact vibration with two interfaces: strings-bridge, and bridge feet-top plate. In this paper, the mobility of an isolated bridge under in-plane excitation is explored using finite element modeling based on the contact vibration model. Numerical results show that the dynamic contact stiffness in the two contact interfaces has a great impact on the bridge mobility. A main resonance peak is observed in the frequency range of 2–3 kHz in the frequency response of the isolated bridge when the contact stiffness is smaller than a critical threshold. The main resonance peak frequency is affected by the contact stiffness as well. In order to verify the numerical findings, a novel experimental system is then designed on the basis of a piezoelectric dynamometer for bridge mobility analysis. Experimental results confirm the impact of the dynamic contact stiffness on the bridge mobility.
Spatial noise in staring IR focal plane arrays
International Nuclear Information System (INIS)
Scribner, D.A.; Kruer, M.R.; Sarkady, K.; Gridley, J.C.
1988-01-01
Problems with nonuniformity correction algorithms due to nonlinear pixel response and 1/f noise have been shown previously to cause spatial noise which can be significantly greater than temporal noise. The residual spatial noise after correction cannot be reduced with time averaging. Because of spatial noise the sensitivity of staring FPA sensors is often less than predicted on the basis of the temporal noise of the individual elements. A review is given of methods for measuring and analyzing spatial noise (after nonuniformity correction) in staring infrared focal plane arrays. Automated measurement techniques are described briefly, including necessary equipment and data reduction procedures. An example of spatial noise measurements is given using a staring InSb Charge Injection Device (CID) array
In-Plane MEMS Shallow Arch Beam for Mechanical Memory
Hafiz, Md Abdullah Al; Kosuru, Lakshmoji; Ramini, Abdallah; Chappanda, Karumbaiah N.; Younis, Mohammad I.
2016-01-01
We demonstrate a memory device based on the nonlinear dynamics of an in-plane microelectromechanical systems (MEMS) clamped–clamped beam resonator, which is deliberately fabricated as a shallow arch. The arch beam is made of silicon, and is electrostatically actuated. The concept relies on the inherent quadratic nonlinearity originating from the arch curvature, which results in a softening behavior that creates hysteresis and co-existing states of motion. Since it is independent of the electrostatic force, this nonlinearity gives more flexibility in the operating conditions and allows for lower actuation voltages. Experimental results are generated through electrical characterization setup. Results are shown demonstrating the switching between the two vibrational states with the change of the direct current (DC) bias voltage, thereby proving the memory concept.
On the C*-algebras of foliations in the plane
Wang, Xiaolu
1987-01-01
The main result of this original research monograph is the classification of C*-algebras of ordinary foliations of the plane in terms of a class of -trees. It reveals a close connection between some most recent developments in modern analysis and low-dimensional topology. It introduces noncommutative CW-complexes (as the global fibred products of C*-algebras), among other things, which adds a new aspect to the fast-growing field of noncommutative topology and geometry. The reader is only required to know basic functional analysis. However, some knowledge of topology and dynamical systems will be helpful. The book addresses graduate students and experts in the area of analysis, dynamical systems and topology.
Optimal interconnection trees in the plane theory, algorithms and applications
Brazil, Marcus
2015-01-01
This book explores fundamental aspects of geometric network optimisation with applications to a variety of real world problems. It presents, for the first time in the literature, a cohesive mathematical framework within which the properties of such optimal interconnection networks can be understood across a wide range of metrics and cost functions. The book makes use of this mathematical theory to develop efficient algorithms for constructing such networks, with an emphasis on exact solutions. Marcus Brazil and Martin Zachariasen focus principally on the geometric structure of optimal interconnection networks, also known as Steiner trees, in the plane. They show readers how an understanding of this structure can lead to practical exact algorithms for constructing such trees. The book also details numerous breakthroughs in this area over the past 20 years, features clearly written proofs, and is supported by 135 colour and 15 black and white figures. It will help graduate students, working mathematicians, ...
Dissipative dark matter and the Andromeda plane of satellites
International Nuclear Information System (INIS)
Randall, Lisa; Scholtz, Jakub
2015-01-01
We show that dissipative dark matter can potentially explain the large observed mass to light ratio of the dwarf satellite galaxies that have been observed in the recently identified planar structure around Andromeda, which are thought to result from tidal forces during a galaxy merger. Whereas dwarf galaxies created from ordinary disks would be dark matter poor, dark matter inside the galactic plane not only provides a source of dark matter, but one that is more readily bound due to the dark matter's lower velocity. This initial N-body study shows that with a thin disk of dark matter inside the baryonic disk, mass-to-light ratios as high as O(90) can be generated when tidal forces pull out patches of sizes similar to the scales of Toomre instabilities of the dark disk. A full simulation will be needed to confirm this result
On the Optimization of Aerospace Plane Ascent Trajectory
Al-Garni, Ahmed; Kassem, Ayman Hamdy
A hybrid heuristic optimization technique based on genetic algorithms and particle swarm optimization has been developed and tested for trajectory optimization problems with multi-constraints and a multi-objective cost function. The technique is used to calculate control settings for two types for ascending trajectories (constant dynamic pressure and minimum-fuel-minimum-heat) for a two-dimensional model of an aerospace plane. A thorough statistical analysis is done on the hybrid technique to make comparisons with both basic genetic algorithms and particle swarm optimization techniques with respect to convergence and execution time. Genetic algorithm optimization showed better execution time performance while particle swarm optimization showed better convergence performance. The hybrid optimization technique, benefiting from both techniques, showed superior robust performance compromising convergence trends and execution time.
In-Plane MEMS Shallow Arch Beam for Mechanical Memory
Hafiz, Md Abdullah Al
2016-10-18
We demonstrate a memory device based on the nonlinear dynamics of an in-plane microelectromechanical systems (MEMS) clamped–clamped beam resonator, which is deliberately fabricated as a shallow arch. The arch beam is made of silicon, and is electrostatically actuated. The concept relies on the inherent quadratic nonlinearity originating from the arch curvature, which results in a softening behavior that creates hysteresis and co-existing states of motion. Since it is independent of the electrostatic force, this nonlinearity gives more flexibility in the operating conditions and allows for lower actuation voltages. Experimental results are generated through electrical characterization setup. Results are shown demonstrating the switching between the two vibrational states with the change of the direct current (DC) bias voltage, thereby proving the memory concept.
Radiation of Electron in the Field of Plane Light Wave
International Nuclear Information System (INIS)
Zelinsky, A.; Drebot, I.V.; Grigorev, Yu.N.; Zvonareva, O.D.; Tatchyn, R.
2006-01-01
Results of integration of a Lorentz equation for a relativistic electron moving in the field of running, plane, linear polarized electromagnetic wave are presented in the paper. It is shown that electron velocities in the field of the wave are almost periodic functions of time. For calculations of angular spectrum of electron radiation intensity expansion of the electromagnetic field in a wave zone into generalized Fourier series was used. Expressions for the radiation intensity spectrum are presented in the paper. Derived results are illustrated for electron and laser beam parameters of NSC KIPT X-ray generator NESTOR. It is shown that for low intensity of the interacting electromagnetic wave the results of energy and angular spectrum calculations in the frame of classical electrodynamics completely coincide with calculation results produced using quantum electrodynamics. Simultaneously, derived expressions give possibilities to investigate dependence of energy and angular Compton radiation spectrum on phase of interaction and the interacting wave intensity
In-plane sampling requirements of MR reprojection angiography
International Nuclear Information System (INIS)
MacFall, J.R.; Grist, T.M.; Spritzer, C.E.; Evans, A.J.
1989-01-01
MR angiograms constructed by reprojection of rapid, sequential, thin-section, flow-compensated acquisitions can produce good-quality images of vasculature. When many sections are required, an unrealistic acquisition time of several hours will be needed if the in-plane resolution is 128 x 256. The scan time can be reduced by using a smaller number (Np) of phase-encoding steps. If the reprojection direction is parallel to the phase-encoding direction, the resolution of the resulting angiogram is preserved. The amount of possible reduction of Np was investigated by acquiring data with varying resolution in the phase-encoding direction through reduction of the phase-encoding gradient. The signal of a typical vessel improved by more than a factor of five as the resolution was reduced, with little loss in the quality of the angiogram. This indicated that scan time for this technique could be reduced
Trapped waves on the mid-latitude β-plane
Paldor, Nathan; Sigalov, Andrey
2008-08-01
A new type of approximate solutions of the Linearized Shallow Water Equations (LSWE) on the mid-latitude β-plane, zonally propagating trapped waves with Airy-like latitude-dependent amplitude, is constructed in this work, for sufficiently small radius of deformation. In contrast to harmonic Poincare and Rossby waves, these newly found trapped waves vanish fast in the positive half-axis, and their zonal phase speed is larger than that of the corresponding harmonic waves for sufficiently large meridional domains. Our analysis implies that due to the smaller radius of deformation in the ocean compared with that in the atmosphere, the trapped waves are relevant to observations in the ocean whereas harmonic waves typify atmospheric observations. The increase in the zonal phase speed of trapped Rossby waves compared with that of harmonic ones is consistent with recent observations that showed that Sea Surface Height features propagated westwards faster than the phase speed of harmonic Rossby waves.
Computing Strongly Homotopic Line Simplification in the Plane
DEFF Research Database (Denmark)
Daneshpajou, Shervin; Abam, Mohammad; Deleuran, Lasse Kosetski
We study a variant of the line-simplification problem where we are given a polygonal path P = p1 , p2 , . . . , pn and a set S of m point obstacles in a plane, and the goal is to find the optimal homotopic simplification, that is, a minimum subsequence Q = q1 , q2 , . . . , qk (q1 = p1 and qk = pn...... ) of P defining a polygonal path which approximates P within the given error ε and is homotopic to P . We assume all shortcuts pi,pj whose errors under a distance function F are at most ε can be computed in TF(n) time where TF(n) is polynomial for all widely-used distance functions. We define the new...
Fluctuation diamagnetism near surfaces and twinning planes in superconductors
International Nuclear Information System (INIS)
Burmistrov, S.N.; Dubovskii, L.B.
1984-01-01
Fluctuations of the magnetic moment and of the specific heat near surfaces and twinning planes in superconductors are studied. Fluctuations near a surface yield an additional contribution to the effect of the usual bulk fluctuations on the diamagnetic moment. Such an additional contribution has a singularity near a temperature T/sub c/3(H), which is higher than the bulk superconducting transition temperature in a magnetic field T/sub c/2(H). Depending on the strength of the magnetic field, the singularity of the additional contribution to the magnetic moment can be either logarithmic (strong fields) or of square-root type (weak fields). Experiments which could reveal the aforementioned anomalous behavior are discussed in detail
In-plane shear test of fibre reinforced concrete panels
DEFF Research Database (Denmark)
Solgaard, Anders Ole Stubbe; Stang, Henrik; Goltermann, Per
2008-01-01
The present paper concerns the investigation of polymer Fiber Reinforced Concrete (FRC) panels subjected to in-plane shear. The use of fibers as primary reinforcement in panels is a new application of fiber reinforcement, hence test methods, design bases and models are lacking. This paper...... contributes to the investigation of fibers as reinforcement in panels with experimental results and a consistent approach to material characterization and modeling. The proposed model draws on elements from the classical yield line theory of rigid, perfectly plastic materials and the theory of fracture...... mechanics. Model panels have been cast to investigate the correlation between the load bearing capacity and the amount of fibers (vol. %) in the mixture. The type of fibers in the mixture was Poly Vinyl Alcohol (PVA) fibers, length 8 mm, diameter 0.04 mm. The mechanical properties of the FRC have been...
Plane parallel radiance transport for global illumination in vegetation
Energy Technology Data Exchange (ETDEWEB)
Max, N.; Mobley, C.; Keating, B.; Wu, E.H.
1997-01-05
This paper applies plane parallel radiance transport techniques to scattering from vegetation. The leaves, stems, and branches are represented as a volume density of scattering surfaces, depending only on height and the vertical component of the surface normal. Ordinary differential equations are written for the multiply scattered radiance as a function of the height above the ground, with the sky radiance and ground reflectance as boundary conditions. They are solved using a two-pass integration scheme to unify the two-point boundary conditions, and Fourier series for the dependence on the azimuthal angle. The resulting radiance distribution is used to precompute diffuse and specular `ambient` shading tables, as a function of height and surface normal, to be used in rendering, together with a z-buffer shadow algorithm for direct solar illumination.
A collapse pressure prediction model for horizontal shale gas wells with multiple weak planes
Directory of Open Access Journals (Sweden)
Ping Chen
2015-01-01
Full Text Available Since collapse of horizontal wellbore through long brittle shale interval is a major problem, the occurrence characteristics of weak planes were analyzed according to outcrop, core, and SEM and FMI data of shale rocks. A strength analysis method was developed for shale rocks with multiple weak planes based on weak-plane strength theory. An analysis was also conducted of the strength characteristics of shale rocks with uniform distribution of multiple weak planes. A collapse pressure prediction model for horizontal wells in shale formation with multiple weak planes was established, which takes into consideration the occurrence of each weak plane, wellbore stress condition, borehole azimuth, and in-situ stress azimuth. Finally, a case study of a horizontal shale gas well in southern Sichuan Basin was conducted. The results show that the intersection angle between the shale bedding plane and the structural fracture is generally large (nearly orthogonal; with the increase of weak plane number, the strength of rock mass declines sharply and is more heavily influenced by weak planes; when there are more than four weak planes, the rock strength tends to be isotropic and the whole strength of rock mass is greatly weakened, significantly increasing the risk of wellbore collapse. With the increase of weak plane number, the drilling fluid density (collapse pressure to keep borehole stability goes up gradually. For instance, the collapse pressure is 1.04 g/cm3 when there are no weak planes, and 1.55 g/cm3 when there is one weak plane, and 1.84 g/cm3 when there are two weak planes. The collapse pressure prediction model for horizontal wells proposed in this paper presented results in better agreement with those in actual situation. This model, more accurate and practical than traditional models, can effectively improve the accuracy of wellbore collapse pressure prediction of horizontal shale gas wells.
Observations of EMIC Triggered Emissions off the Magnetic Equatorial Plane
Grison, B.; Breuillard, H.; Santolik, O.; Cornilleau-Wehrlin, N.
2016-12-01
On 19/08/2005 Cluster spacecraft had their perigee close to the dayside of the Earth magnetic equatorial plane, at about 14 hours Magnetic Local Time. The spacecraft crossed the equator from the southern hemisphere toward the northern hemisphere. In the Southern hemisphere, at about -23° magnetic latitude (MLAT) and at distance of 5.25 Earth Radii from Earth, Cluster 3 observes an EMIC triggered emission between the He+ and the proton local gyrofrequencies. The magnetic waveform (STAFF instrument data) is transformed into the Fourier space for a study based on single value decomposition (SVD) analysis. The emission lasts about 30s. The emission frequency rises from 1Hz up to 1.9Hz. The emission polarization is left-hand, its coherence value is high and the propagation angle is field aligned (lower than 30º). The Poynting flux orientation could not be established. Based on previous study results, these properties are indicative of an observation in vicinity of the source region of the triggered emission. From our knowledge this is the first time that EMIC triggered emission are observed off the magnetic equator. In order to identify the source region we study two possibilities: a source region at higher latitudes than the observations (and particles orbiting in "Shabansky" orbits) and a source region close to the magnetic equatorial plane, as reported in previous studies. We propose to identify the source region from ray tracing analysis and to compare the observed propagation angle in several frequency ranges to the ray tracing results.
Dual-plane ultrasound flow measurements in liquid metals
International Nuclear Information System (INIS)
Büttner, Lars; Nauber, Richard; Burger, Markus; Czarske, Jürgen; Räbiger, Dirk; Franke, Sven; Eckert, Sven
2013-01-01
An ultrasound measurement system for dual-plane, two-component flow velocity measurements especially in opaque liquids is presented. Present-day techniques for measuring local flow structures in opaque liquids disclose considerable drawbacks concerning line-wise measurement of single ultrasound probes. For studying time-varying flow patterns, conventional ultrasound techniques are either limited by time-consuming mechanical traversing or by the sequential operation of single probes. The measurement system presented within this paper employs four transducer arrays with a total of 100 single elements which allows for flow mapping without mechanical traversing. A high frame rate of several 10 Hz has been achieved due to an efficient parallelization scheme using time-division multiplexing realized by a microcontroller-based electronic switching matrix. The functionality and capability of the measurement system are demonstrated on a liquid metal flow at room temperature inside a cube driven by a rotating magnetic field (RMF). For the first time, the primary and the secondary flow have been studied in detail and simultaneously using a configuration with two crossed measurement planes. The experimental data confirm predictions made by numeric simulation. After a sudden switching on of the RMF, inertial oscillations of the secondary flow were observed by means of a time-resolved measurement with a frame rate of 3.4 Hz. The experiments demonstrate that the presented measurement system is able to investigate complex and transient flow structures in opaque liquids. Due to its ability to study the temporal evolution of local flow structures, the measurement system could provide considerable progress for fluid dynamics research, in particular for applications in the food industry or liquid metal technologies. (paper)
Dual-plane ultrasound flow measurements in liquid metals
Büttner, Lars; Nauber, Richard; Burger, Markus; Räbiger, Dirk; Franke, Sven; Eckert, Sven; Czarske, Jürgen
2013-05-01
An ultrasound measurement system for dual-plane, two-component flow velocity measurements especially in opaque liquids is presented. Present-day techniques for measuring local flow structures in opaque liquids disclose considerable drawbacks concerning line-wise measurement of single ultrasound probes. For studying time-varying flow patterns, conventional ultrasound techniques are either limited by time-consuming mechanical traversing or by the sequential operation of single probes. The measurement system presented within this paper employs four transducer arrays with a total of 100 single elements which allows for flow mapping without mechanical traversing. A high frame rate of several 10 Hz has been achieved due to an efficient parallelization scheme using time-division multiplexing realized by a microcontroller-based electronic switching matrix. The functionality and capability of the measurement system are demonstrated on a liquid metal flow at room temperature inside a cube driven by a rotating magnetic field (RMF). For the first time, the primary and the secondary flow have been studied in detail and simultaneously using a configuration with two crossed measurement planes. The experimental data confirm predictions made by numeric simulation. After a sudden switching on of the RMF, inertial oscillations of the secondary flow were observed by means of a time-resolved measurement with a frame rate of 3.4 Hz. The experiments demonstrate that the presented measurement system is able to investigate complex and transient flow structures in opaque liquids. Due to its ability to study the temporal evolution of local flow structures, the measurement system could provide considerable progress for fluid dynamics research, in particular for applications in the food industry or liquid metal technologies.
UNbizplanner: herramienta de software para preparar planes de negocios
Directory of Open Access Journals (Sweden)
Oscar Ávila Cifuentes
2008-01-01
Full Text Available Actualmente las universidades esperan jugar un nuevo papel en la sociedad además de investigar y enseñar, aplicar la “tercera misión” de desarrollo socioeconómico. Por lo cual, las universidades desempeñan un papel importante en el fortalecimiento de la creación de empresas a través del entrenamiento en planes de negocios. Un plan de ne-gocios es un documento que resume cómo un emprendedor creará una organización para explotar una oportuni-dad comercial. Preparar un plan de negocios requiere de una gran cantidad de conocimientos en diferentes dis-ciplinas: finanzas; gestión humana, de derechos de propiedad intelectual, de cadenas de abastecimiento y de ope-rariones y mercadeo, entre otras. En este artículo se presenta una herramienta computacional que sirve como so-porte en la elaboración de un plan de negocios, desde la perspectiva colombiana, identificando las etapas más re-levantes tenidas en cuenta por entidades nacionales que tienen mayor trayectoria en el apoyo a la creación y con-solidación de empresas. Para desarrollar el software se hizo énfasis en las etapas de análisis, diseño e implemen-tación del ciclo de vida de desarrollo de sistemas. Durante la etapa de análisis fue importante la revisión de la lite-ratura sobre planes de negocio teniendo en cuenta el caso colombiano.