Closed-form plastic collapse loads of pipe bends under combined pressure and in-plane bending

International Nuclear Information System (INIS)

Oh, Chang Sik; Kim, Yun Jae

2006-01-01

Based on three-dimensional (3-D) FE limit analyses, this paper provides plastic limit, collapse and instability load solutions for pipe bends under combined pressure and in-plane bending. The plastic limit loads are determined from FE limit analyses based on elastic-perfectly plastic materials using the small geometry change option, and the FE limit analyses using the large geometry change option provide plastic collapse loads (using the twice-elastic-slope method) and instability loads. For the bending mode, both closing bending and opening bending are considered, and a wide range of parameters related to the bend geometry is considered. Based on the FE results, closed-form approximations of plastic limit and collapse load solutions for pipe bends under combined pressure and bending are proposed

Anomalies and inflow on D-branes and O-planes

International Nuclear Information System (INIS)

Scrucca, Claudio A.; Serone, Marco

1999-01-01

We derive the general form of the anomaly for chiral spinors and self-dual antisymmetric tensors living on D-brane and O-plane intersections, using both path-integral and index theorem methods. We then show that the anomalous couplings to RR forms of D-branes and O-planes in a general background are precisely those required to cancel these anomalies through the inflow mechanism. This allows, for instance, for local anomaly cancellation in generic orientifold models, the relevant Green-Schwarz term being given by the sum of the anomalous couplings of all the D-branes and O-planes in the model

A new dimension for piezo actuators: free-form out-of-plane displacement of single piezo layers

International Nuclear Information System (INIS)

Wapler, Matthias C; Brunne, Jens; Wallrabe, Ulrike

2013-01-01

We present a controlled mode of ‘topological’ displacement of homogeneous piezo films that arises solely from an inhomogeneous in-plane strain due to an inhomogeneous polarization. For the rotationally symmetric case, we develop a theoretical model that analytically relates the shape of the displacement to the polarization for the cases of in-plane and out-of-plane polarization. This is verified experimentally for several examples, and we further demonstrate controlled asymmetric deformations. (fast track communication)

Models of Quantum Space Time: Quantum Field Planes

OpenAIRE

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.

Two-plane symmetry in the structural organization of man.

Science.gov (United States)

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.

Phase formation and strain relaxation of Ga2O3 on c-plane and a-plane sapphire substrates as studied by synchrotron-based x-ray diffraction

Science.gov (United States)

Cheng, Zongzhe; Hanke, Michael; Vogt, Patrick; Bierwagen, Oliver; Trampert, Achim

2017-10-01

Heteroepitaxial Ga2O3 was deposited on c-plane and a-plane oriented sapphire by plasma-assisted molecular beam epitaxy and probed by ex-situ and in-situ synchrotron-based x-ray diffraction. The investigation on c-plane sapphire determined a critical thickness of around 33 Å, at which the monoclinic β-phase forms on top of the hexagonal α-phase. A 143 Å thick single phase α-Ga2O3 was observed on a-plane sapphire, much thicker than the α-Ga2O3 on c-plane sapphire. The α-Ga2O3 relaxed very fast in the first 30 Å in both out-of-plane and in-plane directions as measured by the in-situ study.

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.)

The elementary discussion of volumetric modulated arc therapy using the orthogonal plane dose verification

International Nuclear Information System (INIS)

Shi Jinping; Chen Lixin; Xie Qiuying; Zhang Liwen; Teng Jianjian

2012-01-01

Objective: This study was to explore the feasibility of using the orthogonal plane dose formed by the coronal and sagittal plane to verify the volumetric modulated arc therapy (VMAT) plan. Methods: The VMAT plans of 12 patients were included in this study. The orthogonal plane dose formed by the coronal and sagittal plane were measured based on the combination of 2D ionization chamber array and multicube phantom, and the point dose were measured based on a multiple hole cylindrical phantom attached with two 0.125 cm 3 ionization chamber probes. Results: In the measurement of the point dose, the average error was 1.5% in high dose area (more than 80% of maximum), and 1.7% in low dose area (less than 80% of maximum), respectively. The discrepancy of point dose measurement was 1.3% between the 2D ionization chamber array and the VMAT planning system. In the measurement of the orthogonal plane dose, the pass rate of γ were 93.7% for 2%/2 mm and 97.2% for 3%/3 mm. Conclusion: It is reliable for using the orthogonal plane dose formed by the coronal and sagittal plane to verify the VMAT plan. (authors)

Force Lines in Plane Stress

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...

Colliding almost-plane gravitational waves: Colliding plane waves and general properties of almost-plane-wave spacetimes

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

Competition between invariant habit plane and compatible junction plane in TiNb-based shape memory alloy

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

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)

Projecting non-diffracting waves with intermediate-plane holography.

Science.gov (United States)

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.

Analysis of Relative Parallelism Between Hamular-Incisive-Papilla Plane and Campers Plane in Edentulous Subjects: A Comparative Study.

Science.gov (United States)

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.

Implementing digital holograms to create and measure complex-plane optical fields

CSIR Research Space (South Africa)

Dudley, Angela L

2016-02-01

Full Text Available The coherent superposition of a Gaussian beam with an optical vortex can be mathematically described to occupy the complex plane. The authors provide a simple analogy between the mathematics, in the form of the complex plane, and the visual...

Nearaffine planes

NARCIS (Netherlands)

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.

NCC-RANSAC: a fast plane extraction method for 3-D range data segmentation.

Science.gov (United States)

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.

A Viewpoint on the Quantity "Plane Angle"

Science.gov (United States)

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.

Neuromorphic infrared focal plane performs sensor fusion on-plane local-contrast-enhancement spatial and temporal filtering

Science.gov (United States)

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.

MBE growth and characterization of ZnTe epilayers on m-plane sapphire substrates

Energy Technology Data Exchange (ETDEWEB)

Nakasu, Taizo; Sun, Wei-Che; Yamashita, Sotaro; Aiba, Takayuki; Taguri, Kosuke [Department of Electrical Engineering and Bioscience, Waseda University, Tokyo 169-8555 (Japan); Kobayashi, Masakazu [Department of Electrical Engineering and Bioscience, Waseda University, Tokyo 169-8555 (Japan); Kagami Memorial Research Institute for Materials Science and Technology, Waseda University, 2-8-26, Tokyo 169-0051 (Japan); Asahi, Toshiaki [Technology Development Center, JX Nippon Mining and Metals Corporation, Hitachi 317-0056 (Japan); Togo, Hiroyoshi [NTT Microsystem Integration Laboratories, Atsugi 243-0198 (Japan)

2014-07-15

ZnTe epilayers were grown on transparent (10-10) oriented (m -plane) sapphire substrates by molecular beam epitaxy (MBE). Pole figure imaging was used to study the domain distribution within the layer. (211)-oriented ZnTe domains were formed on m -plane sapphire. The presence of only one kind of (211) ZnTe domain formed on the 2 -tilted m -plane sapphire substrates was confirmed. Thus, single domain (211) ZnTe epilayers can be grown on the m -plane sapphire using MBE. Although differences in the crystal structure and lattice mismatch are large, precise control of the substrate surface lattice arrangement result in the formation of high-quality epitaxial layers. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

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....

Peptidoglycan architecture can specify division planes in Staphylococcus aureus.

Science.gov (United States)

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.

Plane Symmetric Dark Energy Models in the Form of Wet Dark Fluid in f ( R, T) Gravity

Science.gov (United States)

Chirde, V. R.; Shekh, S. H.

2016-06-01

In this paper, we have investigated the plane symmetric space-time with wet dark fluid (WDF), which is a candidate for dark energy, in the framework of f ( R, T) gravity Harko et al. 2011, Phys. Rev. D, 84, 024020), where R and T denote the Ricci scalar and the trace of the energy-momentum tensor respectively. We have used the equation of state in the form of WDF for the dark energy component of the Universe. It is modeled on the equation of state p = ω( ρ - ρ ∗). The exact solutions to the corresponding field equations are obtained for power-law and exponential volumetric expansion. The geometrical and physical parameters for both the models are studied. Also, we have discussed the well-known astrophysical phenomena, namely the look-back time, proper distance, the luminosity distance and angular diameter distance with red shift.

Influence of the narrow {111} planes on axial and planar ion channeling.

Science.gov (United States)

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.

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.

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

Science.gov (United States)

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.

Role of moving planes and moving spheres following Dupin cyclides

KAUST Repository

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.

Role of moving planes and moving spheres following Dupin cyclides

KAUST Repository

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.

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.

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...

Current-voltage characteristic of parallel-plane ionization chamber with inhomogeneous ionization

International Nuclear Information System (INIS)

Stoyanov, D G

2007-01-01

The balances of particles and charges in the volume of parallel-plane ionization chamber are considered. Differential equations describing the distribution of current densities in the chamber volume are obtained. As a result of the differential equations solution an analytical form of the current-voltage characteristic of parallel-plane ionization chamber with inhomogeneous ionization in the volume is obtained

Current-voltage characteristic of parallel-plane ionization chamber with inhomogeneous ionization

Energy Technology Data Exchange (ETDEWEB)

Stoyanov, D G [Faculty of Engineering and Pedagogy in Sliven, Technical University of Sofia, 59, Bourgasko Shaussee Blvd, 8800 Sliven (Bulgaria)

2007-08-15

The balances of particles and charges in the volume of parallel-plane ionization chamber are considered. Differential equations describing the distribution of current densities in the chamber volume are obtained. As a result of the differential equations solution an analytical form of the current-voltage characteristic of parallel-plane ionization chamber with inhomogeneous ionization in the volume is obtained.

Mathematical Foundation for Plane Covering Using Hexagons

Science.gov (United States)

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.

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

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.

The elastic strain energy of crystallographic shear planes in reduced tungsten trioxide

International Nuclear Information System (INIS)

Iguchi, E.; Tilley, R.J.D.

1977-01-01

Calculations of the elastic strain energy due to crystallographic shear (c.s.) planes lying upon 102, 103 and 001 planes in reduced tungsten trioxide crystals have been made. The cases analysed in detail are for both isolated c.s. planes and for pairs of c.s. planes. These results are used to determine the elastic strain energy per unit volume for crystals containing ordered arrays of c.s. planes. It was found that the magnitude of the elastic strain energy was in the sequence 001 < 102 < 103 and that at relatively small inter-c.s. spacings the curves of elastic strain energy against c.s. plane separation take the form of a series of peaks and valleys. These results are compared with experimental observations of c.s. plane spacings in substantially reduced crystals containing quasi-ordered arrays of c.s. planes and with observations of c.s. plane nucleation and growth in both slightly and more appreciably reduced crystals. It was found that the elastic strain energy plays a significant part in controlling the microstructure of c.s. plane arrays in such cases. (author)

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)

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.

Diffraction of love waves by two staggered perfectly weak half-planes

International Nuclear Information System (INIS)

Asghar, S.; Zaman, F.D.; Sajida Asghar

1989-01-01

Love wave travelling in a layer of uniform thickness overlying a half-space is assumed to be incident on two parallel but staggered perfectly weak half-planes lying in the upper layer. The diffracted fields is calculated using the modified Wiener-Hopf technique and contour integration method. The diffracted waves satisfy the dispersion relations appropriate to different regions formed by the perfectly weak half-planes

Three-dimensional sheaf of ultrasound planes reconstruction (SOUPR) of ablated volumes.

Science.gov (United States)

Ingle, Atul; Varghese, Tomy

2014-08-01

This paper presents an algorithm for 3-D reconstruction of tumor ablations using ultrasound shear wave imaging with electrode vibration elastography. Radio-frequency ultrasound data frames are acquired over imaging planes that form a subset of a sheaf of planes sharing a common axis of intersection. Shear wave velocity is estimated separately on each imaging plane using a piecewise linear function fitting technique with a fast optimization routine. An interpolation algorithm then computes velocity maps on a fine grid over a set of C-planes that are perpendicular to the axis of the sheaf. A full 3-D rendering of the ablation can then be created from this stack of C-planes; hence the name "Sheaf Of Ultrasound Planes Reconstruction" or SOUPR. The algorithm is evaluated through numerical simulations and also using data acquired from a tissue mimicking phantom. Reconstruction quality is gauged using contrast and contrast-to-noise ratio measurements and changes in quality from using increasing number of planes in the sheaf are quantified. The highest contrast of 5 dB is seen between the stiffest and softest regions of the phantom. Under certain idealizing assumptions on the true shape of the ablation, good reconstruction quality while maintaining fast processing rate can be obtained with as few as six imaging planes suggesting that the method is suited for parsimonious data acquisitions with very few sparsely chosen imaging planes.

Native and denatured forms of proteins can be discriminated at edge plane carbon electrodes

Czech Academy of Sciences Publication Activity Database

Ostatná, Veronika; Černocká, Hana; Kurzatkowska, K.; Paleček, Emil

2012-01-01

Roč. 735, JUL (2012), s. 31-36 ISSN 0003-2670 R&D Projects: GA AV ČR(CZ) KJB100040901; GA ČR(CZ) GAP301/11/2055; GA MŠk(CZ) ME09038 Institutional research plan: CEZ:AV0Z50040702 Keywords : protein denaturation * carbon electrodes * edge plane pyrolytic graphite Subject RIV: BO - Biophysics Impact factor: 4.387, year: 2012

Minimum-link paths among obstacles in the plane

NARCIS (Netherlands)

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

Affine planes, ternary rings, and examples of non-Desarguesian planes

OpenAIRE

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.

In-plane heterostructures of Sb/Bi with high carrier mobility

Science.gov (United States)

Zhao, Pei; Wei, Wei; Sun, Qilong; Yu, Lin; Huang, Baibiao; Dai, Ying

2017-06-01

In-plane two-dimensional (2D) heterostructures have been attracting public attention due to their distinctive properties. However, the pristine materials that can form in-plane heterostructures are reported only for graphene, hexagonal BN, transition-metal dichalcogenides. It will be of great significance to explore more suitable 2D materials for constructing such ingenious heterostructures. Here, we demonstrate two types of novel seamless in-plane heterostructures combined by pristine Sb and Bi monolayers by means of first-principle approach based on density functional theory. Our results indicate that external strain can serve as an effective strategy for bandgap engineering, and the transition from semiconductor to metal occurs when a compressive strain of -8% is applied. In addition, the designed heterostructures possess direct band gaps with high carrier mobility (˜4000 cm2 V-1 s-1). And the mobility of electrons and holes have huge disparity along the direction perpendicular to the interface of Sb/Bi in-plane heterostructures. It is favorable for carriers to separate spatially. Finally, we find that the band edge positions of Sb/Bi in-plane heterostructures can meet the reduction potential of hydrogen generation in photocatalysis. Our results not only offer alternative materials to construct versatile in-plane heterostructures, but also highlight the applications of 2D in-plane heterostructures in diverse nanodevices and photocatalysis.

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)

Bedforms formed by experimental supercritical density flows

Science.gov (United States)

Naruse, Hajime; Izumi, Norihiro; Yokokawa, Miwa; Muto, Tetsuji

2014-05-01

This study reveals characteristics and formative conditions of bedforms produced by saline density flows in supercritical flow conditions, especially focusing on the mechanism of the formation of plane bed. The motion of sediment particles forming bedforms was resolved by high-speed cameras (1/1000 frame/seconds). Experimental density flows were produced by mixtures of salt water (1.01-1.04 in density) and plastic particles (1.5 in specific density, 140 or 240 mm in diameter). Salt water and plastic particles are analogue materials of muddy water and sand particles in turbidity currents respectively. Acrylic flume (4.0 m long, 2.0 cm wide and 0.5 m deep) was submerged in an experimental tank (6.0 m long, 1.8 m wide and 1.2 m deep) that was filled by clear water. Features of bedforms were observed when the bed state in the flume reached equilibrium condition. The experimental conditions range 1.5-4.2 in densimetric Froude number and 0.2-0.8 in Shields dimensionless stress. We report the two major discoveries as a result of the flume experiments: (1) Plane bed under Froude-supercritical flows and (2) Geometrical characteristics of cyclic steps formed by density flows. (1) Plane bed was formed under the condition of supercritical flow regime. In previous studies, plane bed has been known to be formed by subcritical unidirectional flows (ca. 0.8 in Froude number). However, this study implies that plane bed can also be formed by supercritical conditions with high Shields dimensionless stress (>0.4) and very high Froude number (> 4.0). This discovery may suggest that previous estimations of paleo-hydraulic conditions of parallel lamination in turbidites should be reconsidered. The previous experimental studies and data from high-speed camera suggest that the region of plane bed formation coincides with the region of the sheet flow developments. The particle transport in sheet flow (thick bedload layer) induces transform of profile of flow shear stress, which may be

An Algorithm for constructing Hjelmslev planes

OpenAIRE

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...

The principal part of plane vector fields with fixed Newton diagram

International Nuclear Information System (INIS)

Berezovskaya, F.

1991-09-01

Considering the main part of a plane vector field in a neighbourhood of a singular point 0(0,0) it is well known that if the singularity real parts of eigenvalues are non-zero, the linear part of the vector field provides the topological normal form and tangents of all the o-curves. The problem is to find the main part of a plane vector field which would provide the topological orbital normal form in a neighbourhood of singular point and asymptotics of all characteristics trajectories. In this work the solution to the problem for the generic ease of so-called nondegenerate vector fields, using Newton diagram is given. 13 refs, 5 figs

Dynamics of the spatial structure of pulsed discharges in dense gases in point cathode−plane anode gaps and their erosion effect on the plane electrode surface

International Nuclear Information System (INIS)

Baksht, E. Kh.; Blinova, O. M.; Erofeev, M. V.; Karelin, V. I.; Ripenko, V. S.; Tarasenko, V. F.; Trenkin, A. A.; Shibitov, Yu. M.; Shulepov, M. A.

2016-01-01

The dynamics of the spatial structure of the plasma of pulsed discharges in air and nitrogen in a nonuniform electric field and their erosion effect on the plane anode surface were studied experimentally. It is established that, at a nanosecond front of the voltage pulse, a diffuse discharge forms in the point cathode–plane anode gap due to the ionization wave propagating from the cathode. As the gap length decreases, the diffuse discharge transforms into a spark. A bright spot on the anode appears during the diffuse discharge, while the spark channel forms in the later discharge stage. The microstructure of autographs of anode spots and spark channels in discharges with durations of several nanoseconds is revealed. The autographs consist of up to 100 and more microcraters 5–100 μm in diameter. It is shown that, due to the short duration of the voltage pulse, a diffuse discharge can be implemented, several pulses of which do not produce appreciable erosion on the plane anode or the soot coating deposited on it.

Out-of-plane strain effect on silicon-based flexible FinFETs

KAUST Repository

Ghoneim, Mohamed T.; Alfaraj, Nasir; Sevilla, Galo T.; Fahad, Hossain M.; Hussain, Muhammad Mustafa

2015-01-01

Summary form only given. We report out-of-plane strain effect on silicon based flexible FinFET, with sub 20 nm wide fins and hafnium silicate based high-κ gate dielectric. Since ultra-thin inorganic solid state substrates become flexible with reduced thickness, flexing induced strain does not enhance performance. However, detrimental effects arise as the devices are subject to various out-of-plane stresses (compressive and tensile) along the channel length.

Out-of-plane strain effect on silicon-based flexible FinFETs

KAUST Repository

Ghoneim, Mohamed T.

2015-06-21

Summary form only given. We report out-of-plane strain effect on silicon based flexible FinFET, with sub 20 nm wide fins and hafnium silicate based high-κ gate dielectric. Since ultra-thin inorganic solid state substrates become flexible with reduced thickness, flexing induced strain does not enhance performance. However, detrimental effects arise as the devices are subject to various out-of-plane stresses (compressive and tensile) along the channel length.

Ultrasound-Guided Out-of-Plane vs. In-Plane Interscalene Catheters: A Randomized, Prospective Study.

Science.gov (United States)

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.

Three Dimensional Sheaf of Ultrasound Planes Reconstruction (SOUPR) of Ablated Volumes

Science.gov (United States)

Ingle, Atul; Varghese, Tomy

2014-01-01

This paper presents an algorithm for three dimensional reconstruction of tumor ablations using ultrasound shear wave imaging with electrode vibration elastography. Radiofrequency ultrasound data frames are acquired over imaging planes that form a subset of a sheaf of planes sharing a common axis of intersection. Shear wave velocity is estimated separately on each imaging plane using a piecewise linear function fitting technique with a fast optimization routine. An interpolation algorithm then computes velocity maps on a fine grid over a set of C-planes that are perpendicular to the axis of the sheaf. A full three dimensional rendering of the ablation can then be created from this stack of C-planes; hence the name “Sheaf Of Ultrasound Planes Reconstruction” or SOUPR. The algorithm is evaluated through numerical simulations and also using data acquired from a tissue mimicking phantom. Reconstruction quality is gauged using contrast and contrast-to-noise ratio measurements and changes in quality from using increasing number of planes in the sheaf are quantified. The highest contrast of 5 dB is seen between the stiffest and softest regions of the phantom. Under certain idealizing assumptions on the true shape of the ablation, good reconstruction quality while maintaining fast processing rate can be obtained with as few as 6 imaging planes suggesting that the method is suited for parsimonious data acquisitions with very few sparsely chosen imaging planes. PMID:24808405

Designing broad phononic band gaps for in-plane modes

Science.gov (United States)

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.

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

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

Null-plane Bethe-Salpeter dynamics: Mass spectra, decay constants of pseudoscalar mesons, and the pion form factor

International Nuclear Information System (INIS)

Gupta, K.K.; Mitra, A.N.; Singh, N.N.

1990-01-01

A new relativistic definition of the reduced mass (μ 12 ) of a q bar q pair, so as to be in conformity with the standard Wightman-Garding definition of its relative four-momenta q μ , is introduced into the kernel of an ongoing Bethe-Salpeter (BS) program on a two-tier basis. The new definition of μ 12 (involving the hadron mass M) is found to produce a natural Regge asymptotic behavior (M 2 ∼N) in the hadron mass spectra, while retaining the property of an asymptotically linear (∼r) confinement in the three-dimensional structure of the BS kernel. The relativistic structure of μ 12 is responsible for a significant improvement in the fits to the ground-state masses of q bar q and Q bar q mesons as compared to its nonrelativistic definition m 1 m 2 /(m 1 +m 2 ). The leptonic decay constants f p and the charge radii thus calculated are also in excellent agreement with data (π,k) where available, while f p predictions for Q bar q mesons have good overlap with recent lattice predictions. Further, the scaling property (∼k μ -2 ) of the hadron's electromagnetic form factor at large k 2 is a consequence of the ''on-shell'' form of its null-plane wave function. All these results (which are indicated in the barest outline) are preceded by a perspective summary of the theoretical premises and practical working of the BS equation with a four-fermion interaction kernel as a necessary background on a two-tier basis

Origin of the Local Group satellite planes

Science.gov (United States)

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.

COMPARING THE OBSERVABLE PROPERTIES OF DWARF GALAXIES ON AND OFF THE ANDROMEDA PLANE

Energy Technology Data Exchange (ETDEWEB)

Collins, Michelle L. M.; Martin, Nicolas F. [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Rich, R. M. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1547 (United States); Ibata, Rodrigo A. [Observatoire de Strasbourg, 11, Rue de l' Université, F-67000 Strasbourg (France); Chapman, Scott C. [Department of Physics and Atmospheric Science, Dalhousie University, Coburg Road, Halifax B3H1A6 (Canada); McConnachie, Alan W. [NRC Herzberg Institute of Astrophysics, 5071 West Saanich Road, British Columbia, Victoria V9E 2E7 (Canada); Ferguson, Annette M. [Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Irwin, Michael J. [Institute of Astronomy, Madingley Rise, Cambridge CB3 0HA (United Kingdom); Lewis, Geraint F., E-mail: michelle.collins@yale.edu [Sydney Institute for Astronomy, School of Physics, A28, University of Sydney, NSW 2006 (Australia)

2015-01-20

The thin, extended planes of satellite galaxies detected around both the Milky Way and Andromeda are not a natural prediction of the Λ-cold dark matter paradigm. Galaxies in these distinct planes may have formed and evolved in a different way (e.g., tidally) from their off-plane neighbors. If this were the case, one would expect the on- and off-plane dwarf galaxies in Andromeda to have experienced different evolutionary histories, which should be reflected by the chemistries, dynamics, and star formation histories of the two populations. In this work, we present new, robust kinematic observations for two on-plane M31 dwarf spheroidal galaxies (And XVI and XVII) and compile and compare all available observational metrics for the on- and off-plane dwarfs to search for a signal that would corroborate such a hypothesis. We find that, barring their spatial alignment, the on- and off-plane Andromeda dwarf galaxies are indistinguishable from one another, arguing against vastly different formative and evolutionary histories for these two populations.

COMPARING THE OBSERVABLE PROPERTIES OF DWARF GALAXIES ON AND OFF THE ANDROMEDA PLANE

International Nuclear Information System (INIS)

Collins, Michelle L. M.; Martin, Nicolas F.; Rich, R. M.; Ibata, Rodrigo A.; Chapman, Scott C.; McConnachie, Alan W.; Ferguson, Annette M.; Irwin, Michael J.; Lewis, Geraint F.

2015-01-01

The thin, extended planes of satellite galaxies detected around both the Milky Way and Andromeda are not a natural prediction of the Λ-cold dark matter paradigm. Galaxies in these distinct planes may have formed and evolved in a different way (e.g., tidally) from their off-plane neighbors. If this were the case, one would expect the on- and off-plane dwarf galaxies in Andromeda to have experienced different evolutionary histories, which should be reflected by the chemistries, dynamics, and star formation histories of the two populations. In this work, we present new, robust kinematic observations for two on-plane M31 dwarf spheroidal galaxies (And XVI and XVII) and compile and compare all available observational metrics for the on- and off-plane dwarfs to search for a signal that would corroborate such a hypothesis. We find that, barring their spatial alignment, the on- and off-plane Andromeda dwarf galaxies are indistinguishable from one another, arguing against vastly different formative and evolutionary histories for these two populations

Limit load solutions for piping branch junctions under out-of-plane bending

International Nuclear Information System (INIS)

Xu, Ying Hu; Lee, Kuk Hee; Jeon, Jun Young; Kim, Yun Jae

2009-01-01

Approximate plastic limit load solutions for piping branch junctions under out-of plane bending are obtained from detailed three-dimensional (3-D) FE limit analyses based on elastic-perfectly plastic materials with the small geometry change option. Two types of bending are considered; out-of-plane bending to the branch pipe and out-of-plane bending to the run pipe. Accordingly closed-form approximations are proposed for piping branch junctions under out-of-plane bending based on the FE results. The proposed solutions are valid for the branch-to-run pipe radius and thickness from 0.0 to 1.0, and the mean radius-to-thickness ratio of the run pipe from 2.0 to 20.0. And, this study provides effects of reinforcement area on plastic limit loads.

Algebraic Structures on MOD Planes

OpenAIRE

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.

The actuator for micro moving of a body in a plane

International Nuclear Information System (INIS)

Vasiljev, P.; Borodinas, S.; Yoon, S.-J.; Mazeika, D.; Kulvietis, G.

2005-01-01

In present work, the analysis of moving of positioning table in a plane is indicated. For this purpose, only one piezoelectric motor without intermediate parts is created. Being based on researches of compound ultrasonic piezoelectric systems called 'shaking beam' is developed actuator for moving of a body in a plane at any direction. Computer modeling of the actuator is carried out. The prototype is made. The experimental outcomes of the oscillation forms of working surfaces of an actuator are given

Numerical Study on the In-Plane and Out-of-Plane Resistance of Brick Masonry Infill Panels in Steel Frames

Directory of Open Access Journals (Sweden)

Vahid Bahreini

2017-01-01

Full Text Available Masonry infill walls are one of the main forms of interior partitions and exterior walls in many parts of the world. Nevertheless, serious damage and loss of stability of many masonry infill walls had been reported during recent earthquakes. To improve their performance, the interaction between these infill walls and the bounding frames needs to be properly investigated. Such interaction can dramatically increase the stiffness of the frame in the in-plane direction. To avoid the negative aspects of inappropriate interactions between the frame and infill wall, some kind of isolation needs to be introduced. In this paper, three different configurations have been evaluated by using the general finite element software, ABAQUS. Nonlinear pushover and time history analyses have been conducted for each of the three configurations. Results showed that isolation of the infill from the frame has a significant effect on the in-plane response of infilled frames. Furthermore, adequate out-of-plane stability of the infill wall has been achieved. The results show that masonry infill walls that have full contact at the top of the wall but isolated from columns have shown acceptable performance.

Exact expressions for colloidal plane-particle interaction forces and energies with applications to atomic force microscopy

International Nuclear Information System (INIS)

Zypman, F R

2006-01-01

We begin by deriving a general useful theoretical relationship between the plane-particle interaction forces in solution, and the corresponding plane-plane interaction energies. This is the main result of the paper. It provides a simple tool to obtain closed-form particle-plane forces from knowledge of plane-plane interaction energies. To illustrate the simplicity of use of this general formalism, we apply it to find particle-plane interactions within the Derjaguin-Landau-Verwey-Overbeek (DLVO) framework. Specifically, we obtain analytical expressions for forces and interaction energies in the van der Waals and the electrical double layer cases. The van der Waals expression is calculated here for benchmarking purposes and is compared with well-established expressions from Hamaker theory. The interactions for the electric double layer situation are computed in two cases: the linear superposition approximation and the constant surface potential. In both cases, our closed-form expressions were compared with existent numerical results. We also use the main result of this paper to generate an analytical force-separation expression based on atomic force microscope experiments for a tip and surface immersed in an aqueous solution, and compare it with the corresponding numerical results. Finally, based on our main result, we generalize the Derjaguin approximation by calculating the next order of approximation, thus obtaining a formula valuable for colloidal interaction estimations

Microstructure of the regions on a plane copper electrode surface affected by a spark discharge in air in the point-plane gap

Science.gov (United States)

Tren'kin, A. A.; Karelin, V. I.; Shibitov, Yu. M.; Blinova, O. M.; Yasnikov, I. S.

2017-09-01

The microstructure of the regions affected by spark discharge on the surface of a plane copper electrode in atmospheric air in the point-plane gap has been studied using a scanning electron microscope for both the positive and negative polarity of the point electrode. It has been found that the affected regions have the shape of round spots or groups of spots with diameters of individual spots varying in the range of 20-200 μm. It has been revealed that the spots have an internal spatial structure in the form of an aggregate of concentric rings. These rings are aggregates of a large number of microscopic craters with diameters of 0.1-1.0 μm.

The plain truth about forming a plane wave of neutrons

Energy Technology Data Exchange (ETDEWEB)

Wagh, Apoorva G., E-mail: nintsspd@barc.gov.i [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Abbas, Sohrab [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Treimer, Wolfgang [Helmholtz Zentrum Berlin, Glienicker Str. 100, D-14109 Berlin (Germany)

2011-04-01

We have attained the first sub-arcsecond collimation of a monochromatic neutron beam by diffracting neutrons from a Bragg prism, viz. a single crystal prism operating in the vicinity of Bragg incidence. Analytical as well numerical computations based on the dynamical diffraction theory, led to the optimised collimator configuration of a silicon {l_brace}1 1 1{r_brace} Bragg prism for 5.26 A neutrons. We fabricated a Bragg prism to these specifications, tested and operated it at the double diffractometer setup in Helmholtz Zentrum Berlin to produce a 0.58 arcsec wide monochromatic neutron beam. With a similarly optimised Bragg prism analyser of opposite asymmetry, we recorded a 0.62 arcsec wide virgin rocking curve for this ultra-parallel beam. With this nearly plane-wave neutron beam, we have recorded the first ever USANS spectrum in Q{approx}10{sup -6} A{sup -1} range with a hydroxyapatite casein protein sample and demonstrated the instrument capability to characterise agglomerates up to 150 {mu}m in size. The super-collimated monochromatic beam has also enabled us to record the first neutron diffraction pattern from a macroscopic grating of 200 {mu}m period. The transverse coherence length of 175 {mu}m (FWHM) of the ultra-parallel beam derived from the analysis of this pattern, is the greatest achieved to date for A wavelength neutrons.

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])...

In-plane anisotropic strain of elastically and plastically deformed III-nitrides on lithium gallate

Energy Technology Data Exchange (ETDEWEB)

Namkoong, Gon, E-mail: gnamkoon@odu.ed [Old Dominion University, Electrical and Computer Engineering, Applied Research Center, 12050 Jefferson Avenue, Newport News, VA 23606 (United States); Huang, Sa; Moseley, Michael; Doolittle, W. Alan [Georgia Institute of Technology, School of Electrical and Computer Engineering, 777 Atlantic Dr., Atlanta, GA 30332 (United States)

2009-10-30

We have investigated both elastically and plastically deformed GaN films on lithium gallate, LiGaO{sub 2}, by molecular beam epitaxy. The in-plane lattice parameters were determined from high resolution X-ray diffraction and indicated two different groups of in-plane lattice parameters, influenced by the a- and b-axis of LiGaO{sub 2}. The measured in-plane lattice parameters indicate that there exist both compressive and tensile strains of in-plane GaN along the a- and b-axis of LiGaO{sub 2}, respectively. This anisotropic strain in GaN films forms a slight distortion of the basal-plane hexagonal structure of GaN films, leading to a different critical thickness of 4.0 {+-} 0.17 and 7.8 {+-} 0.7 nm along the a- and b-axis of LiGaO{sub 2}, respectively.

In-plane anisotropic strain of elastically and plastically deformed III-nitrides on lithium gallate

International Nuclear Information System (INIS)

Namkoong, Gon; Huang, Sa; Moseley, Michael; Doolittle, W. Alan

2009-01-01

We have investigated both elastically and plastically deformed GaN films on lithium gallate, LiGaO 2 , by molecular beam epitaxy. The in-plane lattice parameters were determined from high resolution X-ray diffraction and indicated two different groups of in-plane lattice parameters, influenced by the a- and b-axis of LiGaO 2 . The measured in-plane lattice parameters indicate that there exist both compressive and tensile strains of in-plane GaN along the a- and b-axis of LiGaO 2 , respectively. This anisotropic strain in GaN films forms a slight distortion of the basal-plane hexagonal structure of GaN films, leading to a different critical thickness of 4.0 ± 0.17 and 7.8 ± 0.7 nm along the a- and b-axis of LiGaO 2 , respectively.

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

Forming parts over small radii

International Nuclear Information System (INIS)

Hazra, S K; Hughes, D J; Pereira, M P; Rolfe, B F

2016-01-01

Stamping simulations usually make the plane stress simplifying assumption. However, this becomes less valid when material draws around features with radius to sheet thickness ratios less than 20. Pereira, Yan and Rolfe (Wear, Vol.265, p.1687 (2008)) predicted that out-of-plane stress equivalent to material yield can occur because a line contact forms briefly at the start of the draw process. The high transient stress can cause high rates of tool wear and may cause the ‘die impact line’ cosmetic defect. In this work, we present residual strain results of a channel section that was drawn over a small radius. Using the neutron source at the Institut Laue-Langevin, in-plane and out-of-plane strains were measured in the channel part to show some support for the conclusions of Pereira et. al. (paper)

Propagation of magnetostatic spin waves in an yttrium iron garnet film for out-of-plane magnetic fields

Science.gov (United States)

Bang, Wonbae; Lim, Jinho; Trossman, Jonathan; Tsai, C. C.; Ketterson, John B.

2018-06-01

We have observed the propagation of spin waves across a thin yttrium iron garnet film on (1 1 1) gadolinium gallium garnet for magnetic fields inclined with respect to the film plane. Two principle planes were studied: that for H in the plane defined by the wave vector k and the plane normal, n, with limiting forms corresponding to the Backward Volume and Forward Volume modes, and that for H in the plane perpendicular to k, with limiting forms corresponding to the Damon-Eshbach and Forward Volume modes. By exciting the wave at one edge of the film and observing the field dependence of the phase of the received signal at the opposing edge we determined the frequency vs. wavevector relation, ω = ω (k), of various propagating modes in the film. Avoided crossings are observed in the Damon-Eshbach and Forward Volume regimes when the propagating mode intersects the higher, exchange split, volume modes, leading to an extinction of the propagating mode; analysis of the resulting behavior allows a determination of the exchange parameter. The experimental results are compared with theoretical simulations.

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

Influence of mandibular fixation method on stability of the maxillary occlusal plane after occlusal plane alteration.

Science.gov (United States)

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.

Out-of-Plane Strain Effects on Physically Flexible FinFET CMOS

KAUST Repository

Ghoneim, Mohamed T.; Alfaraj, Nasir; Torres-Sevilla, Galo A.; Fahad, Hossain M.; Hussain, Muhammad Mustafa

2016-01-01

. The devices were fabricated using the state-of-the-art CMOS technology and then transformed into flexible form by using a CMOS-compatible maskless deep reactive-ion etching technique. Mechanical out-of-plane stresses (compressive and tensile) were applied

Existence of Projective Planes

OpenAIRE

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.

Infinite periodic minimal surfaces and their crystallography in the hyperbolic plane

International Nuclear Information System (INIS)

Sadoc, J.F.; Charvolin, J.

1989-01-01

Infinite periodic minimal surfaces are now being introduced to describe some complex structures with large cells, formed by inorganic and organic materials, which can be considered as crystals of surfaces or films. Among them are the spectacular cubic crystalline structures built by amphiphilic molecules in the presence of water. The crystallographic properties of these surfaces are studied from an intrinsic point of view, using operations of groups of symmetry defined by displacements on their surface. This approach takes advantage of the relation existing between these groups and those characterizing the tilings of the hyperbolic plane. First, the general bases of the particular crystallography of the hyperbolic plane are presented. Then the translation subgroups of the hyperbolic plane are determined in one particular case, that of the tiling involved in the problem of cubic structures of liquid crystals. Finally, it is shown that the infinite periodic minimal surfaces used to describe these structures can be obtained from the hyperbolic plane when some translations are forced to identity. This is indeed formally analogous to the simple process of transformation of a Euclidean plane into a cylinder, when a translation of the plane is forced to identity by rolling the plane onto itself. Thus, this approach transforms the 3D problem of infinite periodic minimal surfaces into a 2D problem and, although the latter is to be treated in a non-Euclidean space, provides a relatively simple formalism for the investigation of infinite periodic surfaces in general and the study of the geometrical transformations relating them. (orig.)

Frequency Equations for the In-Plane Vibration of Circular Annular Disks

Directory of Open Access Journals (Sweden)

S. Bashmal

2010-01-01

Full Text Available This paper deals with the in-plane vibration of circular annular disks under combinations of different boundary conditions at the inner and outer edges. The in-plane free vibration of an elastic and isotropic disk is studied on the basis of the two-dimensional linear plane stress theory of elasticity. The exact solution of the in-plane equation of equilibrium of annular disk is attainable, in terms of Bessel functions, for uniform boundary conditions. The frequency equations for different modes can be obtained from the general solutions by applying the appropriate boundary conditions at the inner and outer edges. The presented frequency equations provide the frequency parameters for the required number of modes for a wide range of radius ratios and Poisson's ratios of annular disks under clamped, free, or flexible boundary conditions. Simplified forms of frequency equations are presented for solid disks and axisymmetric modes of annular disks. Frequency parameters are computed and compared with those available in literature. The frequency equations can be used as a reference to assess the accuracy of approximate methods.

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

Across plane ionic conductivity of highly oriented neodymium doped ceria thin films.

Science.gov (United States)

Baure, G; Kasse, R M; Rudawski, N G; Nino, J C

2015-05-14

A methodology to limit interfacial effects in thin films is proposed and explained. The strategy is to reduce the impact of the electrode interfaces and eliminate cross grain boundaries that impede ionic motion. To this end, highly oriented Nd0.1Ce0.9O2-δ (NDC) nanocrystalline thin films were grown using pulsed laser deposition (PLD) on platinized single crystal a-plane sapphire substrates. High resolution cross-sectional transmission electron microscopy (HR-XTEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) verified the films were textured with columnar grains. The average widths of the columns were approximately 40 nm and not significantly changed by film thickness between 100 and 300 nm. HR-XTEM and XRD determined the {111} planes of NDC were grown preferentially on top of the {111} planes of platinum despite the large lattice mismatch between the two planes. From the XRD patterns, the out of plane strains on the platinum and NDC layers were less than 1%. This can be explained by the coincident site lattice (CSL) theory. Rotating the {111} ceria planes 19.11° with respect to the {111} platinum planes forms a Σ7 boundary where 1 in 7 cerium lattice sites are coincident with the platinum lattice sites. This orientation lowers interfacial energy promoting the preferential alignment of those two planes. The across plane ionic conductivity was measured at low temperatures (<350 °C) for the various film thicknesses. It is here shown that columnar grain growth of ceria can be induced on platinized substrates allowing pathways that are clear of blocking grain boundaries that cause conductivities to diminish as film thickness decreases.

Determining the ice-binding planes of antifreeze proteins by fluorescence-based ice plane affinity.

Science.gov (United States)

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.

Transformational plane geometry

CERN Document Server

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...

"A Tale of Two Planes": Deep Versus Superficial Serratus Plane Block for Postmastectomy Pain Syndrome.

Science.gov (United States)

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.

Continuous shear - a method for studying material elements passing a stationary shear plane

DEFF Research Database (Denmark)

Lindegren, Maria; Wiwe, Birgitte; Wanheim, Tarras

2003-01-01

circumferential groove. Normally shear in metal forming processes is of another nature, namely where the material elements move through a stationary shear zone, often of small width. In this paper a method enabling the simulation of this situation is presented. A tool for continuous shear has beeen manufactured...... and tested with AlMgSil and copper. The sheared material has thereafter been tested n plane strain compression with different orientation concerning the angle between the shear plane and the compression direction....

Electronic Transport Mechanism for Schottky Diodes Formed by Au/HVPE a-Plane GaN Templates Grown via In Situ GaN Nanodot Formation

Directory of Open Access Journals (Sweden)

Moonsang Lee

2018-06-01

Full Text Available We investigate the electrical characteristics of Schottky contacts for an Au/hydride vapor phase epitaxy (HVPE a-plane GaN template grown via in situ GaN nanodot formation. Although the Schottky diodes present excellent rectifying characteristics, their Schottky barrier height and ideality factor are highly dependent upon temperature variation. The relationship between the barrier height, ideality factor, and conventional Richardson plot reveals that the Schottky diodes exhibit an inhomogeneous barrier height, attributed to the interface states between the metal and a-plane GaN film and to point defects within the a-plane GaN layers grown via in situ nanodot formation. Also, we confirm that the current transport mechanism of HVPE a-plane GaN Schottky diodes grown via in situ nanodot formation prefers a thermionic field emission model rather than a thermionic emission (TE one, implying that Poole–Frenkel emission dominates the conduction mechanism over the entire range of measured temperatures. The deep-level transient spectroscopy (DLTS results prove the presence of noninteracting point-defect-assisted tunneling, which plays an important role in the transport mechanism. These electrical characteristics indicate that this method possesses a great throughput advantage for various applications, compared with Schottky contact to a-plane GaN grown using other methods. We expect that HVPE a-plane GaN Schottky diodes supported by in situ nanodot formation will open further opportunities for the development of nonpolar GaN-based high-performance devices.

An introduction to finite projective planes

CERN Document Server

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

Mobility-Aware Modeling and Analysis of Dense Cellular Networks With $C$ -Plane/ $U$ -Plane Split Architecture

KAUST Repository

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.

The plane strain shear fracture of the advanced high strength steels

International Nuclear Information System (INIS)

Sun, Li

2013-01-01

The “shear fracture” which occurs at the high-curvature die radii in the sheet metal forming has been reported to remarkably limit the application of the advanced high strength steels (AHSS) in the automobile industry. However, this unusual fracture behavior generally cannot be predicted by the traditional forming limit diagram (FLD). In this research, a new experimental system was developed in order to simulate the shear fracture, especially at the plane strain state which is the most common state in the auto-industry and difficult to achieve in the lab due to sample size. Furthermore, the system has the capability to operate in a strain rate range from quasi-static state to the industrial forming state. One kinds of AHSS, Quenching-Partitioning (QP) steels have been performed in this test and the results show that the limiting fracture strain is related to the bending ratio and strain rate. The experimental data support that deformation-induced heating is an important cause of “shear fracture” phenomena for AHSS: a deformation-induced quasi-heating caused by smaller bending ratio and high strain rate produce a smaller limiting plane strain and lead a “shear fracture” in the component

Ultrasound-Guided Out-of-Plane vs. In-Plane Interscalene Catheters: A Randomized, Prospective Study

OpenAIRE

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-...

Reliability of twin-dependent triple junction distributions measured from a section plane

International Nuclear Information System (INIS)

Hardy, Graden B.; Field, David P.

2016-01-01

Numerous studies indicate polycrystalline triple junctions are independent microstructural features with distinct properties from their constituent grain boundaries. Despite the influence of triple junctions on material properties, it is impractical to characterize triple junctions on a large scale using current three-dimensional methods. This work demonstrates the ability to characterize twin-dependent triple junction distributions from a section plane by adopting a grain boundary plane stereology. The technique is validated through simulated distributions and simulated electron back-scatter diffraction (EBSD) data. Measures of validation and convergence are adopted to demonstrate the quantitative reliability of the technique as well as the convergence behavior of twin-dependent triple junction distributions. This technique expands the characterization power of EBSD and prepares the way for characterizing general triple junction distributions from a section plane. - Graphical abstract: The distribution of planes forming a triple junction with a given twin boundary is shown partially in the stereographic projections below from a given projection. The plot on the left shows the ideal/measured distribution and the plot on the right shows the distribution obtained from the stereological method presented here.

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.

Epitaxial growth of M-plane GaN on ZnO micro-rods by plasma-assisted molecular beam epitaxy

Directory of Open Access Journals (Sweden)

Shuo-Ting You

2015-12-01

Full Text Available We have studied the GaN grown on ZnO micro-rods by plasma-assisted molecular beam epitaxy. From the analyses of GaN microstructure grown on non-polar M-plane ZnO surface ( 10 1 ̄ 0 by scanning transmission electron microscope, we found that the ZnGa2O4 compound was formed at the M-plane hetero-interface, which was confirmed by polarization-dependent photoluminescence. We demonstrated that the M-plane ZnO micro-rod surface can be used as an alternative substrate to grow high quality M-plane GaN epi-layers.

Systems considerations in mosaic focal planes

Science.gov (United States)

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 spectral dynamic stiffness method for free vibration analysis of plane elastodynamic problems

Science.gov (United States)

Liu, X.; Banerjee, J. R.

2017-03-01

A highly efficient and accurate analytical spectral dynamic stiffness (SDS) method for modal analysis of plane elastodynamic problems based on both plane stress and plane strain assumptions is presented in this paper. First, the general solution satisfying the governing differential equation exactly is derived by applying two types of one-dimensional modified Fourier series. Then the SDS matrix for an element is formulated symbolically using the general solution. The SDS matrices are assembled directly in a similar way to that of the finite element method, demonstrating the method's capability to model complex structures. Any arbitrary boundary conditions are represented accurately in the form of the modified Fourier series. The Wittrick-Williams algorithm is then used as the solution technique where the mode count problem (J0) of a fully-clamped element is resolved. The proposed method gives highly accurate solutions with remarkable computational efficiency, covering low, medium and high frequency ranges. The method is applied to both plane stress and plane strain problems with simple as well as complex geometries. All results from the theory in this paper are accurate up to the last figures quoted to serve as benchmarks.

Active point out-of-plane ultrasound calibration

Science.gov (United States)

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.

Hyperbolic Cosines and Sines Theorems for the Triangle Formed by Arcs of Intersecting Semicircles on Euclidean Plane

Directory of Open Access Journals (Sweden)

Robert M. Yamaleev

2013-01-01

Full Text Available The hyperbolic cosines and sines theorems for the curvilinear triangle bounded by circular arcs of three intersecting circles are formulated and proved by using the general complex calculus. The method is based on a key formula establishing a relationship between exponential function and the cross-ratio. The proofs are carried out on Euclidean plane.

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

NUMERICAL DERIVATIONS OF A MACROSCOPIC MODEL FOR REINFORCED CONCRETE WALLS CONSIDERING IN-PLANE AND OUT-OF-PLANE BEHAVIOR

OpenAIRE

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 ...

Communication: Recovering the flat-plane condition in electronic structure theory at semi-local DFT cost

Science.gov (United States)

Bajaj, Akash; Janet, Jon Paul; Kulik, Heather J.

2017-11-01

The flat-plane condition is the union of two exact constraints in electronic structure theory: (i) energetic piecewise linearity with fractional electron removal or addition and (ii) invariant energetics with change in electron spin in a half filled orbital. Semi-local density functional theory (DFT) fails to recover the flat plane, exhibiting convex fractional charge errors (FCE) and concave fractional spin errors (FSE) that are related to delocalization and static correlation errors. We previously showed that DFT+U eliminates FCE but now demonstrate that, like other widely employed corrections (i.e., Hartree-Fock exchange), it worsens FSE. To find an alternative strategy, we examine the shape of semi-local DFT deviations from the exact flat plane and we find this shape to be remarkably consistent across ions and molecules. We introduce the judiciously modified DFT (jmDFT) approach, wherein corrections are constructed from few-parameter, low-order functional forms that fit the shape of semi-local DFT errors. We select one such physically intuitive form and incorporate it self-consistently to correct semi-local DFT. We demonstrate on model systems that jmDFT represents the first easy-to-implement, no-overhead approach to recovering the flat plane from semi-local DFT.

Influence of temperature on δ-hydride habit plane in α-Zirconium

International Nuclear Information System (INIS)

Singh, R. N.; Stahle, P.; Banerjee, S.; Ristmanaa, Matti; Sauramd, K.

2008-01-01

Dilute Zr-alloy with hcp α-Zr as major phase is used as pressure boundary for hot coolant in CANDU, PHWR and RBMK reactors. Hydrogen / deuterium ingress during service makes the pressure boundary components like pressure tubes of the aforementioned reactors susceptible to hydride embrittlement. Hydride acquires plate shaped morphology and the broad face of the hydride plate coincides with certain crystallographic plane of α-Zr crystal, which is called habit plane. Hydride plate oriented normal to tensile stress significantly increases the degree of embrittlement. Thus key to mitigating the damage due to hydride embrittlement is to avoid the formation of hydride plates normal to tensile stress. Two different theoretical approaches are used to determine the habit plane of precipitates viz., geometrical and solid mechanics. For the geometrical approach invariant plane and invariant-line criteria have been applied successfully and for the solid mechanics approach strain energy minimization criteria have been used successfully. Solid mechanics approach using strain energy computed by FEM technique has been applied to hydride precipitation in Zr-alloys, but the emphasis has been to understand the solvus hysteresis. The objective of the present investigation is to predict the habit plane of δ-hydride precipitating in α-Zr at 25, 300, 400 and 450 .deg. C. using strain energy minimization technique. The δ-hydride phase is modeled to undergo isotropic elastic and plastic deformation. The α-Zr phase was modeled to undergo transverse isotropic elastic deformation. Both isotropic plastic and transverse isotropic plastic deformations of α-Zr were considered. Further, both perfect and linear work-hardening plastic behaviors were considered. Accommodation strain energy of δ-hydrides forming in α-Zr crystal was computed using initial strain method as a function of hydride nuclei orientation. Hydride was modeled as disk with circular edge. The simulation was carried out

Incorporating the Uncertainties of Nodal-Plane Orientation in the Seismo-Lineament Analysis Method (SLAM)

Science.gov (United States)

Cronin, V.; Sverdrup, K. A.

2013-05-01

The process of delineating a seismo-lineament has evolved since the first description of the Seismo-Lineament Analysis Method (SLAM) by Cronin et al. (2008, Env & Eng Geol 14(3) 199-219). SLAM is a reconnaissance tool to find the trace of the fault that produced an shallow-focus earthquake by projecting the corresponding nodal planes (NP) upward to their intersections with the ground surface, as represented by a DEM or topographic map. A seismo-lineament is formed by the intersection of the uncertainty volume associated with a given NP and the ground surface. The ground-surface trace of the fault that produced the earthquake is likely to be within one of the two seismo-lineaments associated with the two NPs derived from the earthquake's focal mechanism solution. When no uncertainty estimate has been reported for the NP orientation, the uncertainty volume associated with a given NP is bounded by parallel planes that are [1] tangent to the ellipsoidal uncertainty volume around the focus and [2] parallel to the NP. If the ground surface is planar, the resulting seismo-lineament is bounded by parallel lines. When an uncertainty is reported for the NP orientation, the seismo-lineament resembles a bow tie, with the epicenter located adjacent to or within the "knot." Some published lists of focal mechanisms include only one NP with associated uncertainties. The NP orientation uncertainties in strike azimuth (+/- gamma), dip angle (+/- epsilon) and rake that are output from an FPFIT analysis (Reasenberg and Oppenheimer, 1985, USGS OFR 85-739) are taken to be the same for both NPs (Oppenheimer, 2013, pers com). The boundaries of the NP uncertainty volume are each comprised by planes that are tangent to the focal uncertainty ellipsoid. One boundary, whose nearest horizontal distance from the epicenter is greater than or equal to that of the other boundary, is formed by the set of all planes with strike azimuths equal to the reported NP strike azimuth +/- gamma, and dip angle

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)

Semantic Versus Syntactic Cutting Planes

OpenAIRE

Filmus, Yuval; Hrubeš, 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...

Evaluation of uterine peristalsis using cine MRI on the coronal plane in comparison with the sagittal plane.

Science.gov (United States)

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.

On the determination of general plane stress states in orthotropic materials from ultrasonic velocity data in non symmetry planes

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)

Determination of Stress Coefficient Terms in Cracked Solids for Monoclinic Materials with Plane Symmetry at x3 = 0

Science.gov (United States)

Yuan, F. G.

1998-01-01

Determination of all the coefficients in the crack tip field expansion for monoclinic materials under two-dimensional deformation is presented in this report. For monoclinic materials with a plane of material symmetry at x(sub 3) = 0, the in-plane deformation is decoupled from the anti-plane deformation. In the case of in-plane deformation, utilizing conservation laws of elasticity and Betti's reciprocal theorem, together with selected auxiliary fields, T-stress and third-order stress coefficients near the crack tip are evaluated first from path-independent line integrals. To determine the T-stress terms using the J-integral and Betti's reciprocal work theorem, auxiliary fields under a concentrated force and moment acting at the crack tip are used respectively. Through the use of Stroh formalism in anisotropic elasticity, analytical expressions for all the coefficients including the stress intensity factors are derived in a compact form that has surprisingly simple structure in terms of the Barnett-Lothe tensors, L. The solution forms for degenerated materials, orthotropic, and isotropic materials are presented.

Lower incisor inclination regarding different reference planes.

Science.gov (United States)

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.

Conformal Collineations of the Ricci and Energy-Momentum Tensors in Static Plane Symmetric Space-Times

Science.gov (United States)

Akhtar, S. S.; Hussain, T.; Bokhari, A. H.; Khan, F.

2018-04-01

We provide a complete classification of static plane symmetric space-times according to conformal Ricci collineations (CRCs) and conformal matter collineations (CMCs) in both the degenerate and nondegenerate cases. In the case of a nondegenerate Ricci tensor, we find a general form of the vector field generating CRCs in terms of unknown functions of t and x subject to some integrability conditions. We then solve the integrability conditions in different cases depending upon the nature of the Ricci tensor and conclude that the static plane symmetric space-times have a 7-, 10- or 15-dimensional Lie algebra of CRCs. Moreover, we find that these space-times admit an infinite number of CRCs if the Ricci tensor is degenerate. We use a similar procedure to study CMCs in the case of a degenerate or nondegenerate matter tensor. We obtain the exact form of some static plane symmetric space-time metrics that admit nontrivial CRCs and CMCs. Finally, we present some physical applications of our obtained results by considering a perfect fluid as a source of the energy-momentum tensor.

Coalescence of two equal cylinders: exact results for creeping viscous plane flow driven by capillarity

International Nuclear Information System (INIS)

Hopper, R.W.

1984-01-01

The coalescence of two equal viscous cylinders under the influence of capillarity is of interest in the theory of sintering. Although the flow in typical cylinder coalescence experiments is not planar, the plane-flow case is of general interest and is a good approximation in the early stage. An essentially exact analytic solution giving the shape as a function of time for slow plane flow is presented in simple closed form. 16 references, 2 figures, 1 table

The influence of air-filled structures on wave propagation and beam formation of a pygmy sperm whale (Kogia breviceps) in horizontal and vertical planes.

Science.gov (United States)

Song, Zhongchang; Zhang, Yu; Thornton, Steven W; Li, Songhai; Dong, Jianchen

2017-10-01

The wave propagation, sound field, and transmission beam pattern of a pygmy sperm whale (Kogia breviceps) were investigated in both the horizontal and vertical planes. Results suggested that the signals obtained at both planes were similarly characterized with a high peak frequency and a relatively narrow bandwidth, close to the ones recorded from live animals. The sound beam measured outside the head in the vertical plane was narrower than that of the horizontal one. Cases with different combinations of air-filled structures in both planes were used to study the respective roles in controlling wave propagation and beam formation. The wave propagations and beam patterns in the horizontal and vertical planes elucidated the important reflection effect of the spermaceti and vocal chambers on sound waves, which was highly significant in forming intensive forward sound beams. The air-filled structures, the forehead soft tissues and skull structures formed wave guides in these two planes for emitted sounds to propagate forward.

Radiation dosimetry with plane-parallel ionization chambers: An international (IAEA) code of practice

International Nuclear Information System (INIS)

Andreo, P.

1996-01-01

Research on plane-parallel ionization chambers since the IAEA Code of Practice (TRS-277) was published in 1987 has expanded our knowledge on perturbation and other correction factors in ionization chamber dosimeter, and also constructional details of these chambers have been shown to be important. Different national organizations have published, or are in the process of publishing, recommendations on detailed procedures for the calibration and use of plane-parallel ionization chambers. An international working group was formed under the auspices of the IAEA, first to assess the status and validity of IAEA TRS-277, and second to develop an international Code of Practice for the calibration and use of plane-parallel ionization chambers in high-energy electron and photon beams. The purpose of this work is to describe the forthcoming Code of Practice. (author). 39 refs, 3 figs, 2 tabs

Radiation dosimetry with plane-parallel ionization chambers: An international (IAEA) code of practice

Energy Technology Data Exchange (ETDEWEB)

Andreo, P [Lunds Hospital, Lund (Sweden). Radiophysics Dept.; Almond, P R [J.G. Brown Cancer Center, Univ. of Lousville, Lousville, KY (United States). Dept. of Radiation Oncology; Mattsson, O [Sahlgrenska Hospital, Gothenburg (Sweden). Dept. of Radiation Physics; Nahum, A E [Royal Marsden Hospital, Sutton (United Kingdom). Joint Dept. of Physics; Roos, M [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany)

1996-08-01

Research on plane-parallel ionization chambers since the IAEA Code of Practice (TRS-277) was published in 1987 has expanded our knowledge on perturbation and other correction factors in ionization chamber dosimeter, and also constructional details of these chambers have been shown to be important. Different national organizations have published, or are in the process of publishing, recommendations on detailed procedures for the calibration and use of plane-parallel ionization chambers. An international working group was formed under the auspices of the IAEA, first to assess the status and validity of IAEA TRS-277, and second to develop an international Code of Practice for the calibration and use of plane-parallel ionization chambers in high-energy electron and photon beams. The purpose of this work is to describe the forthcoming Code of Practice. (author). 39 refs, 3 figs, 2 tabs.

Dislocation content of geometrically necessary boundaries aligned with slip planes in rolled aluminium

DEFF Research Database (Denmark)

Hong, Chuanshi; Huang, Xiaoxu; Winther, Grethe

2013-01-01

Previous studies have revealed that dislocation structures in metals with medium-to-high stacking fault energy, depend on the grain orientation and therefore on the slip systems. In the present work, the dislocations in eight slip-plane-aligned geometrically necessary boundaries (GNBs) in three...... expected active dominate. The dislocations predicted inactive are primarily attributed to dislocation reactions in the boundary. Two main types of dislocation networks in the boundaries were identified: (1) a hexagonal network of the three dislocations in the slip plane with which the boundary was aligned......; two of these come from the active slip systems, the third is attributed to dislocation reactions (2) a network of three dislocations from both of the active slip planes; two of these react to form Lomer locks. The results indicate a systematic boundary formation process for the GNBs. Redundant...

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

Exact partial solution to the compressible flow problems of jet formation and penetration in plane, steady flow

International Nuclear Information System (INIS)

Karpp, R.R.

1984-01-01

The particle solution of the problem of the symmetric impact of two compressible fluid stream is derived. The plane two-dimensional flow is assumed to be steady, and the inviscid compressible fluid is of the Chaplygin (tangent gas) type. The equations governing this flow are transformed to the hodograph plane where an exact, closed-form solution for the stream function is obtained. The distribution of fluid properties along the plane of symmetry and the shape of free surface streamlines are determined by transformation back to the physical plane. The problem of a compressible fluid jet penetrating an infinite target of similar material is also solved by considering a limiting case of this solution. Differences between compressible and incompressible flows of the type considered are illustrated

An improved integrally formed radio frequency quadrupole

Science.gov (United States)

Abbott, S.R.

1987-10-05

An improved radio frequency quadrupole is provided having an elongate housing with an elongate central axis and top, bottom and two side walls symmetrically disposed about the axis, and vanes formed integrally with the walls, the vanes each having a cross-section at right angles to the central axis which tapers inwardly toward the axis to form electrode tips spaced from each other by predetermined distances. Each of the four walls, and the vanes integral therewith, is a separate structural element having a central lengthwise plane passing through the tip of the vane, the walls having flat mounting surfaces at right angles to and parallel to the control plane, respectively, which are butted together to position the walls and vane tips relative to each other. 4 figs.

Scattering of three-dimensional plane waves in a self-reinforced half-space lying over a triclinic half-space

Science.gov (United States)

Gupta, Shishir; Pramanik, Abhijit; Smita; Pramanik, Snehamoy

2018-06-01

The phenomenon of plane waves at the intersecting plane of a triclinic half-space and a self-reinforced half-space is discussed with possible applications during wave propagation. Analytical expressions of the phase velocities of reflection and refraction for quasi-compressional and quasi-shear waves under initial stress are discussed carefully. The closest form of amplitude proportions on reflection and refraction factors of three quasi-plane waves are developed mathematically by applying appropriate boundary conditions. Graphics are sketched to exhibit the consequences of initial stress in the three-dimensional plane wave on reflection and refraction coefficients. Some special cases that coincide with the fundamental properties of several layers are designed to express the reflection and refraction coefficients.

A Design of 45-Degree Dual-Polarization Broadband Plane Station Antenna

Directory of Open Access Journals (Sweden)

Jianming Zhou

2015-01-01

Full Text Available A new broadband planar dual-polarization base station antenna is proposed, the antenna consists of two broadband plane coplanar base station antenna units, and so it has features of plane antenna. Two broadband plane station antenna units can, respectively, form double polarization in the direction. We analyzed the relative positions between the two antenna units and their effects on the performances of the antenna, especially for the influence of isolation. Broadband antenna has the characteristics of the broadband station antenna, and bandwidth is also guaranteed. The measured results show that the antenna can obtain 45% relative bandwidth, and 30 dB isolation degree also can be got, and the radiation performance is also good. Measurement results confirmed that the antenna gain can be guaranteed among 48% relative bandwidth, 15 dB of gain is got among bandwidth of 1.69–2.78 GHz, the isolation degree of different polarization method can reach 30 dB, and the measurement gain of two polarization methods of antenna both can reach 8.5 dBi.

Coherent field propagation between tilted planes.

Science.gov (United States)

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.

Fault plane orientations of deep earthquakes in the Izu-Bonin-Marianas subduction zone system

Science.gov (United States)

Myhill, R.; Warren, L. M.

2011-12-01

We present the results of directivity analysis on 45 deep earthquakes within the Izu-Bonin-Marianas subduction zone between 1993 and 2011. The age of the subducting Pacific plate increases from north to south along the trench, from 120 Ma offshore Tokyo to over 150 Ma east of the Mariana Islands. The dip of the deep slab generally increases from north to south, and is steep to overturned beneath the southern Bonin Islands and Marianas. Between 34 and 26 degrees north, a peak in seismicity at 350-450 km depth marks a decrease in dip as the slab approaches the base of the upper mantle. We observe directivity for around 60 percent of the analysed earthquakes, and use the propagation characteristics to find the best fitting rupture vector. In 60-70 percent of cases with well constrained rupture directivity, the best fitting rupture vector allows discrimination of the fault plane and the auxiliary plane of the focal mechanism. The identified fault planes between 100 km and 500 km are predominantly near-horizontal or south-southwest dipping. Rotated into the plane of the slab, the fault plane poles form a single cluster, since the more steeply dipping fault planes are found within more steeply dipping sections of slab. The dominance of near-horizontal fault planes at intermediate depth agrees with results from previous studies of the Tonga and Middle-America subduction zones. However, the presence of a single preferred fault plane orientation for large deep-focus earthquakes has not been previously reported, and contrasts with the situation for deep-focus earthquakes in the Tonga-Kermadec subduction system. Ruptures tend to propagate away from the top surface of the slab. We discuss potential causes of preferred fault plane orientations within subducting slabs in the light of existing available data, and the implications for mechanisms of faulting at great depths within the Earth.

Materials, devices, techniques, and applications for Z-plane focal plane array technology; Proceedings of the Meeting, Orlando, FL, Mar. 29, 30, 1989

Science.gov (United States)

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.

On the necessity of connection between plane and curve space metrics in gravity theory on a plane background

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''

Effect of indium accumulation on the characteristics of a-plane InN epi-films under different growth conditions

Energy Technology Data Exchange (ETDEWEB)

Lo, Yun-Yo [Institute of Photonics, National Changhua University of Education, Changhua, Taiwan, ROC (China); Huang, Man-Fang, E-mail: mfhuang@cc.ncue.edu.tw [Institute of Photonics, National Changhua University of Education, Changhua, Taiwan, ROC (China); Chiang, Yu-Chia [Institute of Photonics, National Changhua University of Education, Changhua, Taiwan, ROC (China); Fan, Jenn-Chyuan [Department of Electronic Engineering, Nan Kai University of Technology, Nantou, Taiwan, ROC (China)

2015-08-31

This study investigated the influence of indium accumulation happened on the surface of a-plane InN grown under different growth conditions. Three different growth rates with N/In ratio from stoichiometric to N-rich were used to grow a-plane InN epifilms on GaN-buffered r-plane sapphires by plasma-assisted molecular beam epitaxy. When a-plane InN was grown above 500 °C with a high growth rate, abnormally high in-situ reflectivity was found during a-plane InN growth, which was resulted from indium accumulation on surface owing to In-N bonding difficulty on certain crystal faces of a-plane InN surface. Even using excess N-flux, indium accumulation could still be found in initial growth and formed 3-dimension-like patterns on a-plane InN surface which resulted in rough surface morphology. By reducing growth rate, surface roughness was improved because indium atoms could have more time to migrate to suitable position. Nonetheless, basal stacking fault density and crystal anisotropic property were not affected by growth rate. - Highlights: • High growth temperature could cause indium accumulation on a-plane InN surface. • Indium accumulation on a-plane InN surface causes rough surface. • Low growth rate improves surface morphology but not crystal quality.

Soft Gravitons & the Memory Effect for Plane Gravitational Waves

OpenAIRE

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...

Dual plane problems for creeping flow of power-law incompressible medium

Directory of Open Access Journals (Sweden)

Dmitriy S. Petukhov

2016-09-01

Full Text Available In this paper, we consider the class of solutions for a creeping plane flow of incompressible medium with power-law rheology, which are written in the form of the product of arbitrary power of the radial coordinate by arbitrary function of the angular coordinate of the polar coordinate system covering the plane. This class of solutions represents the asymptotics of fields in the vicinity of singular points in the domain occupied by the examined medium. We have ascertained the duality of two problems for a plane with wedge-shaped notch, at which boundaries in one of the problems the vector components of the surface force vanish, while in the other—the vanishing components are the vector components of velocity, We have investigated the asymptotics and eigensolutions of the dual nonlinear eigenvalue problems in relation to the rheological exponent and opening angle of the notch for the branch associated with the eigenvalue of the Hutchinson–Rice–Rosengren problem learned from the problem of stress distribution over a notched plane for a power law medium. In the context of the dual problem we have determined the velocity distribution in the flow of power-law medium at the vertex of a rigid wedge, We have also found another two eigenvalues, one of which was determined by V. V. Sokolovsky for the problem of power-law fluid flow in a convergent channel.

Open Cluster Dynamics via Fundamental Plane

Science.gov (United States)

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.

Plane-wave least-squares reverse-time migration

KAUST Repository

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.

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...

Fast Plane Wave Imaging

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...

Evaluation of planar 3D electrical capacitance tomography: from single-plane to dual-plane configuration

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)

Plastic loads of pipe bends under combined pressure and out-of-plane bending

International Nuclear Information System (INIS)

Lee, Kuk Hee; Kim, Yun Jae; Park, Chi Yong; Lee, Sung Ho; Kim, Tae Ryong

2007-01-01

Based on three-Dimensional (3-D) FE limit analyses, this paper provides plastic limit and TES(Twice- Elastic-Slope) loads for pipe bends under combined pressure and out-of-plane bending. The plastic limit loads are determined from FE limit analyses based on elastic.perfectly-plastic materials using the small geometry change option, and the FE limit analyses using the large geometry change option provide TES plastic loads. A wide range of parameters related to the bend geometry is considered. Based on the FE results, closed-form approximations of plastic limit and TES plastic load solutions for pipe bends under out-of-plane bending are proposed

Guide-Plane Retention in Designing Removable Partial Dentures.

Science.gov (United States)

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.

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...

VAST PLANES OF SATELLITES IN A HIGH-RESOLUTION SIMULATION OF THE LOCAL GROUP: COMPARISON TO ANDROMEDA

International Nuclear Information System (INIS)

Gillet, N.; Ocvirk, P.; Aubert, D.; Knebe, A.; Yepes, G.; Libeskind, N.; Gottlöber, S.; Hoffman, Y.

2015-01-01

We search for vast planes of satellites (VPoS) in a high-resolution simulation of the Local Group performed by the CLUES project, which improves significantly the resolution of previous similar studies. We use a simple method for detecting planar configurations of satellites, and validate it on the known plane of M31. We implement a range of prescriptions for modeling the satellite populations, roughly reproducing the variety of recipes used in the literature, and investigate the occurrence and properties of planar structures in these populations. The structure of the simulated satellite systems is strongly non-random and contains planes of satellites, predominantly co-rotating, with, in some cases, sizes comparable to the plane observed in M31 by Ibata et al. However, the latter is slightly richer in satellites, slightly thinner, and has stronger co-rotation, which makes it stand out as overall more exceptional than the simulated planes, when compared to a random population. Although the simulated planes we find are generally dominated by one real structure forming its backbone, they are also partly fortuitous and are thus not kinematically coherent structures as a whole. Provided that the simulated and observed planes of satellites are indeed of the same nature, our results suggest that the VPoS of M31 is not a coherent disk and that one-third to one-half of its satellites must have large proper motions perpendicular to the plane

A Collaborative Knowledge Plane for Autonomic Networks

Science.gov (United States)

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.

Developing a New HSR Switching Node (SwitchBox for Improving Traffic Performance in HSR Networks

Directory of Open Access Journals (Sweden)

Nguyen Xuan Tien

2016-01-01

Full Text Available High availability is crucial for industrial Ethernet networks as well as Ethernet-based control systems such as automation networks and substation automation systems (SAS. Since standard Ethernet does not support fault tolerance capability, the high availability of Ethernet networks can be increased by using redundancy protocols. Various redundancy protocols for Ethernet networks have been developed and standardized, such as rapid spanning tree protocol (RSTP, media redundancy protocol (MRP, parallel redundancy protocol (PRP, high-availability seamless redundancy (HSR and others. RSTP and MRP have switchover delay drawbacks. PRP provides zero recovery time, but requires a duplicate network infrastructure. HSR operation is similar to PRP, but HSR uses a single network. However, the standard HSR protocol is mainly applied to ring-based topologies and generates excessively unnecessary redundant traffic in the network. In this paper, we develop a new switching node for the HSR protocol, called SwitchBox, which is used in HSR networks in order to support any network topology and significantly reduce redundant network traffic, including unicast, multicast and broadcast traffic, compared with standard HSR. By using the SwitchBox, HSR not only provides seamless communications with zero switchover time in case of failure, but it is also easily applied to any network topology and significantly reduces unnecessary redundant traffic in HSR networks.

(211) oriented ZnTe growth on m-plane sapphire by MBE

Energy Technology Data Exchange (ETDEWEB)

Nakasu, Taizo [Department of Electrical Engineering and Bioscience, Waseda University, Tokyo 169-8555 (Japan); Kobayashi, Masakazu [Department of Electrical Engineering and Bioscience, Waseda University, Tokyo 169-8555 (Japan); Kagami Memorial Research Institute for Materials Science and Technology, Waseda University, 2-8-26, Tokyo 169-0051 (Japan); Togo, Hiroyoshi [NTT Microsystem Integration Laboratories, Atugi-shi 243-0198 (Japan); Asahi, Toshiaki [Technology Development Center, JX Nippon Mining and Metals Corporation, Hitachi-shi 317-0056 (Japan)

2013-11-15

Single-crystalline and single domain ZnTe thin films are sought for high-performance terahertz wave detectors, and ZnTe/sapphire heterostructures were considered since the Electro-Optical (EO) effect could be obtained only from epilayers. ZnTe epilayers were grown on m-plane sapphire substrates by molecular beam epitaxy, and the potential of single domain epilayers was explored. Through the X-ray diffraction pole figure measurement it was confirmed that one (100) oriented ZnTe domain along with two kinds of (211) oriented domains were formed on the m-plane sapphire when the layer was grown at 340 C. When the layer was grown at 350 C, the (211) oriented domain dominated the film. (copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

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...

Investigation on the intense fringe formation phenomenon downstream hot-image plane.

Science.gov (United States)

Hu, Yonghua; Li, Guohui; Zhang, Lifu; Huang, Wenti; Chen, Shuming

2015-11-30

The propagation of a high-power flat-topped Gaussian beam, which is modulated by three parallel wirelike scatterers, passing through a downstream Kerr medium slab and free spaces is investigated. A new phenomenon is found that a kind of intense fringe with intensity several times that of the incident beam can be formed in a plane downstream the Kerr medium. This kind of intense fringe is another result in the propagation process of nonlinear imaging and it locates scores of centimeters downstream the predicted hot image plane. Moreover, the intensity of this fringe can achieve the magnitude of that of hot image in corresponding single-scatterer case, and this phenomenon can arise only under certain conditions. As for the corresponding hot images, they are also formed but largely suppressed. The cause of the formation of such an intense fringe is analyzed and found related to interference in the free space downstream the Kerr medium. Moreover, the ways it is influenced by some important factors such as the wavelength of incident beam and the properties of scatterers and Kerr medium are discussed, and some important properties and relations are revealed.

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

Work Planing Automation at Mechanical Subdivision

OpenAIRE

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.

Chromatic X-ray magnifying method and apparatus by Bragg reflective planes on the surface of Abbe sphere

Science.gov (United States)

Thoe, Robert S.

1991-01-01

Method and apparatus for producing sharp, chromatic, magnified images of X-ray emitting objects, are provided. The apparatus, which constitutes an X-ray microscope or telescope, comprises a connected collection of Bragg reflecting planes, comprised of either a bent crystal or a synthetic multilayer structure, disposed on and adjacent to a locus determined by a spherical surface. The individual Bragg planes are spatially oriented to Bragg reflect radiation from the object location toward the image location. This is accomplished by making the Bragg planes spatially coincident with the surfaces of either a nested series of prolate ellipsoids of revolution, or a nested series of spheres. The spacing between the Bragg reflecting planes can be tailored to control the wavelengths and the amount of the X-radiation that is Bragg reflected to form the X-ray image.

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)

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)

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

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 30 Mbps in-plane full-duplex light communication using a monolithic GaN photonic circuit

Science.gov (United States)

Gao, Xumin; Yuan, Jialei; Yang, Yongchao; Li, Yuanhang; Yuan, Wei; Zhu, Guixia; Zhu, Hongbo; Feng, Meixin; Sun, Qian; Liu, Yuhuai; Wang, Yongjin

2017-07-01

We propose, fabricate and characterize photonic integration of a InGaN/GaN multiple-quantum-well light-emitting diode (MQW-LED), waveguide, ring resonator and InGaN/GaN MQW-photodiode on a single chip, in which the photonic circuit is suspended by the support beams. Both experimental observations and simulation results illustrate the manipulation of in-plane light coupling and propagation by the waveguide and the ring resonator. The monolithic photonic circuit forms an in-plane data communication system using visible light. When the two suspended InGaN/GaN MQW-diodes simultaneously serve as the transmitter and the receiver, an in-plane full-duplex light communication is experimentally demonstrated with a transmission rate of 30 Mbps, and the superimposed signals are extracted using the self-interference cancellation method. The suspended photonic circuit creates new possibilities for exploring the in-plane full-duplex light communication and manufacturing complex GaN-based monolithic photonic integrations.

Intercorrelated in-plane and out-of-plane ferroelectricity in ultrathin two-dimensional layered semiconductor In2Se3

KAUST Repository

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.

Intercorrelated in-plane and out-of-plane ferroelectricity in ultrathin two-dimensional layered semiconductor In2Se3

KAUST Repository

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.

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

Causal inheritance in plane wave quotients

Science.gov (United States)

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.

Discovery of a New Fundamental Plane Dictating Galaxy Cluster Evolution from Gravitational Lensing

Science.gov (United States)

Fujita, Yutaka; Umetsu, Keiichi; Rasia, Elena; Meneghetti, Massimo; Donahue, Megan; Medezinski, Elinor; Okabe, Nobuhiro; Postman, Marc

2018-04-01

In cold dark-matter (CDM) cosmology, objects in the universe have grown under the effect of gravity of dark matter. The intracluster gas in a galaxy cluster was heated when the dark-matter halo formed through gravitational collapse. The potential energy of the gas was converted to thermal energy through this process. However, this process and the thermodynamic history of the gas have not been clearly characterized in connection with the formation and evolution of the internal structure of dark-matter halos. Here, we show that observational CLASH data of high-mass galaxy clusters lie on a plane in the three-dimensional logarithmic space of their characteristic radius r s , mass M s , and X-ray temperature T X with a very small orthogonal scatter. The tight correlation indicates that the gas temperature was determined at a specific cluster formation time, which is encoded in r s and M s . The plane is tilted with respect to T X ∝ M s /r s , which is the plane expected in the case of simplified virial equilibrium. We show that this tilt can be explained by a similarity solution, which indicates that clusters are not isolated but continuously growing through matter accretion from their outer environments. Numerical simulations reproduce the observed plane and its angle. This result holds independently of the gas physics implemented in the code, revealing the fundamental origin of this plane.

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

Probing the CuO planes with positrons in high Tc cuprates: theoretical predictions

International Nuclear Information System (INIS)

Barbiellini, B.; Jarlborg, T.; Massidda, S.; Peter, M.

1995-01-01

Positron annihilation spectroscopy is a useful tool to investigate the Fermi surface in high T c superconductors. To study the physics of the copper-oxygen subsystem that forms the Cu-O layers, it is important to provide theoretical predictions, on materials where there is a large overlap between the positron and the interesting Cu-O planes. We have performed first-principle electronic structure calculations obtained using the linear muffin-tin orbital and the full-potential linearized augmented plane wave methods. The positron charge distributions and their sensitivity to different potentials are calculated. Secondly, we have computed the annihilation rates and the electron-positron momentum density in order to give predictions of the Fermi surface signals. (orig.)

Ultrasound Guided Transversus Thoracic Plane block, Parasternal block and fascial planes hydrodissection for internal mammary post thoracotomy pain syndrome.

Science.gov (United States)

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®.

Modular Hamiltonians on the null plane and the Markov property of the vacuum state

Science.gov (United States)

Casini, Horacio; Testé, Eduardo; Torroba, Gonzalo

2017-09-01

We compute the modular Hamiltonians of regions having the future horizon lying on a null plane. For a CFT this is equivalent to regions with a boundary of arbitrary shape lying on the null cone. These Hamiltonians have a local expression on the horizon formed by integrals of the stress tensor. We prove this result in two different ways, and show that the modular Hamiltonians of these regions form an infinite dimensional Lie algebra. The corresponding group of unitary transformations moves the fields on the null surface locally along the null generators with arbitrary null line dependent velocities, but act non-locally outside the null plane. We regain this result in greater generality using more abstract tools on the algebraic quantum field theory. Finally, we show that modular Hamiltonians on the null surface satisfy a Markov property that leads to the saturation of the strong sub-additive inequality for the entropies and to the strong super-additivity of the relative entropy.

Intercorrelated In-Plane and Out-of-Plane Ferroelectricity in Ultrathin Two-Dimensional Layered Semiconductor In2Se3.

Science.gov (United States)

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.

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...

Closed form solution for the finite anti-plane shear field for a class of hyperelastic incompressible brittle solids

Science.gov (United States)

Stolz, Claude

2010-12-01

The equilibrium solution of a damaged zone in finite elasticity is given for a class of hyperelastic materials which does not suffer tension when a critical stretching value is reached. The study is made for a crack in anti-plane shear loading condition. The prescribed loading is that of linearized elastostatics conditions at infinity. The geometry of the damaged zone is found and the stationary propagation is discussed when the inertia terms can be neglected.

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

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 ...

The electro-oxidation of the mixture of formaldehyde and 2-propanol on gold (100 and (111 single crystal planes in alkaline medium

Directory of Open Access Journals (Sweden)

BRANISLAV Z. NIKOLIC

2000-12-01

Full Text Available The effect of formaldehyde on the oxidation of 2-propanol and vice versa on gold single crystal planes (100 and 111 was studied. An activating effect in the reaction of the simultaneous oxidation of 2-propanol and formaldehyde was obtained on a gold (100 plane. In the case of a gold (111 electrode, the activation effect was not obtained. It was concluded that the adsorption of formaldehyde on the electrode surface prevents the adsorption of poisoning species formed during the electro-oxidation of 2-propanol on the Au(100 plane, while this is not the case on the Au(111 plane. The different behaviour is caused by the difference in the symmetry of the surface atoms of these two Au single-crystal planes.

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.

On plane-wave relativistic electrodynamics in plasmas and in vacuum

International Nuclear Information System (INIS)

Fiore, Gaetano

2014-01-01

We revisit the exact microscopic equations (in differential, and equivalent integral form) ruling a relativistic cold plasma after the plane-wave Ansatz, without customary approximations. We show that in the Eulerian description the motion of a very diluted plasma initially at rest and excited by an arbitrary transverse plane electromagnetic travelling-wave has a very simple and explicit dependence on the transverse electromagnetic potential; for a non-zero density plasma the above motion is a good approximation of the real one as long as the back-reaction of the charges on the electromagnetic field can be neglected, i.e. for a time lapse decreasing with the plasma density, and can be used as initial step in an iterative resolution scheme. As one of many possible applications, we use these results to describe how the ponderomotive force of a very intense and short plane laser pulse hitting normally the surface of a plasma boosts the surface electrons into the ion background. In response to this penetration, the electrons are pulled back by the electric force exerted by the ions and the other displaced electrons and may leave the plasma with high energy in the direction opposite to that of propagation of the pulse ‘slingshot effect’ (Fiore G et al 2013 arXiv:1309.1400). (paper)

Compact planes, mostly 8-dimensional. A retrospect

OpenAIRE

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.

Special cases of martensite compatibility: A near single-variant habit-plane and the martensite of nanocrystalline NiTi

Directory of Open Access Journals (Sweden)

Petersmann Manuel

2015-01-01

Full Text Available Lattice parameters measured near the high temperature (~1000°C bcc α to hcp β transformation in an intermetallic Mo-containing γ-TiAl based alloy indicate a middle valued eigenvalue of the corresponding deformation gradient near 1. Habit-planes calculated under the assumption of a simple slip as lattice invariant shear, agree with experimentally determined orientations of the lens like plates recorded via electron backscattering. By contrast, twinning as invariant lattice shear has been investigated in nanocrystalline NiTi. Here the grain size causes the formation mechanism of the martensite to change from a “herring-bone” morphology faciliting a habit-plane between two twinned laminates and the austenite to a single laminate, which in the nonlinear theory formally cannot form a habit-plane with the austenite. Since this might cause high accommodation strains, the effectiveness of stress accommodation of martensite formed in neighboring grains of a polycrystal is investigated. Subsequent numerical microstructural modeling is outlined. The resulting energetically most favorable transformation sequence yields the transformation kinetics.

Nonpolar a-plane GaN grown on r-plane sapphire using multilayer AlN buffer by metalorganic chemical vapor deposition

International Nuclear Information System (INIS)

Chiang, C.H.; Chen, K.M.; Wu, Y.H.; Yeh, Y.S.; Lee, W.I.; Chen, J.F.; Lin, K.L.; Hsiao, Y.L.; Huang, W.C.; Chang, E.Y.

2011-01-01

Mirror-like and pit-free non-polar a-plane (1 1 -2 0) GaN films are grown on r-plane (1 -1 0 2) sapphire substrates using metalorganic chemical vapor deposition (MOCVD) with multilayer high-low-high temperature AlN buffer layers. The buffer layer structure and film quality are essential to the growth of a flat, crack-free and pit-free a-plane GaN film. The multilayer AlN buffer structure includes a thin low-temperature-deposited AlN (LT-AlN) layer inserted into the high-temperature-deposited AlN (HT-AlN) layer. The results demonstrate that the multilayer AlN buffer structure can improve the surface morphology of the upper a-plane GaN film. The grown multilayer AlN buffer structure reduced the tensile stress on the AlN buffer layers and increased the compressive stress on the a-plane GaN film. The multilayer AlN buffer structure markedly improves the surface morphology of the a-plane GaN film, as revealed by scanning electron microscopy. The effects of various growth V/III ratios was investigated to obtain a-plane GaN films with better surface morphology. The mean roughness of the surface was 1.02 nm, as revealed by atomic force microscopy. Accordingly, the multilayer AlN buffer structure improves the surface morphology and facilitates the complete coalescence of the a-plane GaN layer.

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.)

A constitutive framework for modelling thin incompressible viscoelastic materials under plane stress in the finite strain regime

Science.gov (United States)

Kroon, M.

2011-11-01

Rubbers and soft biological tissues may undergo large deformations and are also viscoelastic. The formulation of constitutive models for these materials poses special challenges. In several applications, especially in biomechanics, these materials are also relatively thin, implying that in-plane stresses dominate and that plane stress may therefore be assumed. In the present paper, a constitutive model for viscoelastic materials in the finite strain regime and under the assumption of plane stress is proposed. It is assumed that the relaxation behaviour in the direction of plane stress can be treated separately, which makes it possible to formulate evolution laws for the plastic strains on explicit form at the same time as incompressibility is fulfilled. Experimental results from biomechanics (dynamic inflation of dog aorta) and rubber mechanics (biaxial stretching of rubber sheets) were used to assess the proposed model. The assessment clearly indicates that the model is fully able to predict the experimental outcome for these types of material.

CORRELATIONS OF DISK AND JET EMISSION DEVIATING FROM THE FUNDAMENTAL PLANE

Energy Technology Data Exchange (ETDEWEB)

Lin, Da-Bin; Mu, Hui-Jun; Lu, Zu-Jia; Liang, En-Wei [GXU-NAOC Center for Astrophysics and Space Sciences, Department of Physics, Guangxi University, Nanning 530004 (China); Gu, Wei-Min; Ma, Ren-Yi, E-mail: lindabin@gxu.edu.cn [Department of Astronomy and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005 (China)

2015-07-01

The variability of the accretion rate, which is believed to induce the aperiodic variability of X-ray emission from disks, may affect the energy injection into a jet. In this spirit, a correlation between disk emission and jet emission can be formed even if the mean luminosity of disk emission remains constant. In this work, these correlations are found in the situation in which the luminosity of disk emission is variable and kept at a constant mean value. The obtained correlations may be shallower than that of the fundamental plane of black hole activity. In addition, the slope of correlation may increase with increasing observed frequency of jet emission. For the luminosities spaced over three days, the slope of correlation decreases with increasing black hole mass. The deviation of our found correlations from that of the fundamental plane is related to the suppression of variability in the jet emission in comparison with that in the disk emission. This mechanism may work in some sources in which shallower correlations have been reported. Moreover, it implies that luminosities used to estimate the relation of the fundamental plane should cover an appropriate timescale, in which the variability of jet emission is not significantly suppressed.

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.

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

Quantum Mechanics on the h-deformed Quantum Plane

OpenAIRE

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...

Spin dependence of rotational damping by the rotational plane mapping method

Energy Technology Data Exchange (ETDEWEB)

Leoni, S; Bracco, A; Million, B [Milan Univ. (Italy). Ist. di Fisica; Herskind, B; Dossing, T; Rasmussen, P [Niels Bohr Inst., Copenhagen (Denmark); Bergstrom, M; Brockstedt, A; Carlsson, H; Ekstrom, P; Nordlund, A; Ryde, H [Lund Univ. (Sweden). Dept. of Physics; Ingebretsen, F; Tjom, P O [Oslo Univ. (Norway); Lonnroth, T [Aabo Akademi, Turku (Finland). Dept. of Physics

1992-08-01

In the study of deformed nuclei by gamma spectroscopy, the large quadrupole transition strength known from rotational bands at high excitation energy may be distributed over all final states of a given parity within an interval defined as the rotational damping width {Gamma}{sub rot} The method of rotational plane mapping extracts a value of {Gamma}{sub rot} from the width of valleys in certain planes in the grid plots of triple gamma coincidence data sets. The method was applied to a high spin triple data set on {sup 162,163}Tm taken with NORDBALL at the tandem accelerator of the Niels Bohr Institute, and formed in the reaction {sup 37}Cl + {sup 130}Te. The value {Gamma}{sub rot} = 85 keV was obtained. Generally, experimental values seem to be lower than theoretical predictions, although the only calculation made was for {sup 168}Yb. 6 refs., 3 figs.

Anatomical planes: are we teaching accurate surface anatomy?

Science.gov (United States)

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.

Regularized plane-wave least-squares Kirchhoff migration

KAUST Repository

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.

Progression of spinal deformity in wheelchair-dependent patients with Duchenne muscular dystrophy who are not treated with steroids: coronal plane (scoliosis) and sagittal plane (kyphosis, lordosis) deformity.

Science.gov (United States)

Shapiro, F; Zurakowski, D; Bui, T; Darras, B T

2014-01-01

We determined the frequency, rate and extent of development of scoliosis (coronal plane deformity) in wheelchair-dependent patients with Duchenne muscular dystrophy (DMD) who were not receiving steroid treatment. We also assessed kyphosis and lordosis (sagittal plane deformity). The extent of scoliosis was assessed on sitting anteroposterior (AP) spinal radiographs in 88 consecutive non-ambulatory patients with DMD. Radiographs were studied from the time the patients became wheelchair-dependent until the time of spinal fusion, or the latest assessment if surgery was not undertaken. Progression was estimated using a longitudinal mixed-model regression analysis to handle repeated measurements. Scoliosis ≥ 10° occurred in 85 of 88 patients (97%), ≥ 20° in 78 of 88 (89%) and ≥ 30° in 66 of 88 patients (75%). The fitted longitudinal model revealed that time in a wheelchair was a highly significant predictor of the magnitude of the curve, independent of the age of the patient (p lordosis (16 (27%) abnormal and seven (11%) normal). This study provides a baseline to assess the effects of steroids and other forms of treatment on the natural history of scoliosis in patients with DMD, and an approach to assessing spinal deformity in the coronal and sagittal planes in wheelchair-dependent patients with other neuromuscular disorders.

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].

Study of combined cycle engine for aerospace plane

OpenAIRE

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...

Streptococcus anginosus infections: crossing tissue planes.

Science.gov (United States)

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.

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

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

Comparison of Skeletal and Dental Reference Planes with the Hamulus-Incisive-Papilla Plane: A Pilot Study on 3D Reconstructed Tomographies of the Skull.

Science.gov (United States)

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.

Off-plane x-ray reflection grating fabrication

Science.gov (United States)

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.

Plane-Casting: 3D Cursor Control with a SmartPhone

OpenAIRE

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...

Acoustic backscattering and radiation force on a rigid elliptical cylinder in plane progressive waves.

Science.gov (United States)

Mitri, F G

2016-03-01

This work proposes a formal analytical theory using the partial-wave series expansion (PWSE) method in cylindrical coordinates, to calculate the acoustic backscattering form function as well as the radiation force-per-length on an infinitely long elliptical (non-circular) cylinder in plane progressive waves. The major (or minor) semi-axis of the ellipse coincides with the direction of the incident waves. The scattering coefficients for the rigid elliptical cylinder are determined by imposing the Neumann boundary condition for an immovable surface and solving a resulting system of linear equations by matrix inversion. The present method, which utilizes standard cylindrical (Bessel and Hankel) wave functions, presents an advantage over the solution for the scattering that is ordinarily expressed in a basis of elliptical Mathieu functions (which are generally non-orthogonal). Furthermore, an integral equation showing the direct connection of the radiation force function with the square of the scattering form function in the far-field from the scatterer (applicable for plane waves only), is noted and discussed. An important application of this integral equation is the adequate evaluation of the radiation force function from a bistatic measurement (i.e., in the polar plane) of the far-field scattering from any 2D object of arbitrary shape. Numerical predictions are evaluated for the acoustic backscattering form function and the radiation force function, which is the radiation force per unit length, per characteristic energy density, and per unit cross-sectional surface of the ellipse, with particular emphasis on the aspect ratio a/b, where a and b are the semi-axes, as well as the dimensionless size parameter kb, without the restriction to a particular range of frequencies. The results are particularly relevant in acoustic levitation, acousto-fluidics and particle dynamics applications. Copyright © 2015 Elsevier B.V. All rights reserved.

Moving vertices to make drawings plane

NARCIS (Netherlands)

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

Failure by fracture in bulk metal forming

DEFF Research Database (Denmark)

Silva, C.M.A.; Alves, Luis M.; Nielsen, Chris Valentin

2015-01-01

This paper revisits formability in bulk metal forming in the light of fundamental concepts of plasticity,ductile damage and crack opening modes. It proposes a new test to appraise the accuracy, reliability and validity of fracture loci associated with crack opening by tension and out-of-plane shear...

One-dimensional in-plane edge domain walls in ultrathin ferromagnetic films

Science.gov (United States)

Lund, Ross G.; Muratov, Cyrill B.; Slastikov, Valeriy V.

2018-03-01

We study existence and properties of 1D edge domain walls in ultrathin ferromagnetic films with uniaxial in-plane magnetic anisotropy. In these materials, the magnetization vector is constrained to lie entirely in the film plane, with the preferred directions dictated by the magnetocrystalline easy axis. We consider magnetization profiles in the vicinity of a straight film edge oriented at an arbitrary angle with respect to the easy axis. To minimize the micromagnetic energy, these profiles form transition layers in which the magnetization vector rotates away from the direction of the easy axis to align with the film edge. We prove existence of edge domain walls as minimizers of the appropriate 1D micromagnetic energy functional and show that they are classical solutions of the associated Euler-Lagrange equation with a Dirichlet boundary condition at the edge. We also perform a numerical study of these 1D domain walls and uncover further properties of these domain wall profiles.

Hull Surface Information Retrieval and Optimization of High Speed Planing Craft

International Nuclear Information System (INIS)

Ayob, A F; Wan Nik, W B; Ray, T; Smith, W F

2012-01-01

Traditional approach on ship design involve the use of a method which takes a form that was earlier called the 'general design diagram' and is now known as the 'design spiral' – an iterative ship design process that allows for an increase in complexity and precision across the design cycle. Several advancements have been made towards the design spiral, however inefficient for handling complex simultaneous design changes, especially when later variable changes affect the ship's performance characteristics evaluated in earlier stages. Reviewed in this paper are several advancements in high speed planing craft design in preliminary design stage. An optimization framework for high speed planing craft is discussed which consist of surface information retrieval module, a suite of state-of-the-art optimization algorithms and standard naval architectural performance estimation tools. A summary of the implementation of the proposed hull surface information retrieval and several case studies are presented to demonstrate the capabilities of the framework.

3D plane-wave least-squares Kirchhoff migration

KAUST Repository

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.

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.

A Technique to Facilitate Tooth Modification for Removable Partial Denture Prosthesis Guide Planes.

Science.gov (United States)

Haeberle, C Brent; Abreu, Amara; Metzler, Kurt

2016-07-01

The technique in this article was developed to provide a means to create prepared guide planes of proper dimension to ensure a more stable and retentive removable partial denture prosthesis (RPDP) framework when providing this service for a patient. Using commonly found clinical materials, a paralleling device can be fabricated from the modified diagnostic cast of the patient's dental arch requiring an RPDP. Polymethyl methacrylate or composite added to an altered thermoplastic form can be positioned intraorally and used as a guide to predictably adjust tooth structure for guide planes. Since it can potentially minimize the number of impressions and diagnostic casts made during the procedure, this can help achieve the desired result more efficiently and quickly for the patient. © 2015 by the American College of Prosthodontists.

Theory of Single Point Incremental Forming

DEFF Research Database (Denmark)

Martins, P.A.F.; Bay, Niels; Skjødt, Martin

2008-01-01

This paper presents a closed-form theoretical analysis modelling the fundamentals of single point incremental forming and explaining the experimental and numerical results available in the literature for the past couple of years. The model is based on membrane analysis with bi-directional in-plan......-plane contact friction and is focused on the extreme modes of deformation that are likely to be found in single point incremental forming processes. The overall investigation is supported by experimental work performed by the authors and data retrieved from the literature.......This paper presents a closed-form theoretical analysis modelling the fundamentals of single point incremental forming and explaining the experimental and numerical results available in the literature for the past couple of years. The model is based on membrane analysis with bi-directional in...

Influence of basal-plane dislocation structures on expansion of single Shockley-type stacking faults in forward-current degradation of 4H-SiC p-i-n diodes

Science.gov (United States)

Hayashi, Shohei; Yamashita, Tamotsu; Senzaki, Junji; Miyazato, Masaki; Ryo, Mina; Miyajima, Masaaki; Kato, Tomohisa; Yonezawa, Yoshiyuki; Kojima, Kazutoshi; Okumura, Hajime

2018-04-01

The origin of expanded single Shockley-type stacking faults in forward-current degradation of 4H-SiC p-i-n diodes was investigated by the stress-current test. At a stress-current density lower than 25 A cm-2, triangular stacking faults were formed from basal-plane dislocations in the epitaxial layer. At a stress-current density higher than 350 A cm-2, both triangular and long-zone-shaped stacking faults were formed from basal-plane dislocations that converted into threading edge dislocations near the interface between the epitaxial layer and the substrate. In addition, the conversion depth of basal-plane dislocations that expanded into the stacking fault was inside the substrate deeper than the interface. These results indicate that the conversion depth of basal-plane dislocations strongly affects the threshold stress-current density at which the expansion of stacking faults occurs.

Molecular cloning of plane pollen allergen Pla a 3 and its utility as diagnostic marker for peach associated plane pollen allergy.

Science.gov (United States)

Wangorsch, A; Larsson, H; Messmer, M; García-Moral, A; Lauer, I; Wolfheimer, S; Schülke, S; Bartra, J; Vieths, S; Lidholm, J; Scheurer, S

2016-05-01

Non-specific lipid transfer proteins (nsLTP) are considered to provoke allergic symptoms to plane tree pollen, which are frequently associated with peach allergy. The objective was to clone the cDNA of plane pollen nsLTP Pla a 3, to characterize IgE-binding and allergenic potency of recombinant Pla a 3 in comparison to its natural counterpart and peach nsLTP Pru p 3. Natural Pla a 3 was purified from plane pollen and analysed by mass spectrometry (MS). Recombinant Pla a 3 was characterized by SDS-PAGE and CD spectroscopy. Specific IgE to extract, components of plane pollen and Pru p 3 was measured by ImmunoCAP in sera of patients allergic to either plane pollen (n = 10), peach (n = 15) or both (n = 15). Biological potency of the proteins was investigated by in vitro mediator release assays and IgE cross-reactivity by competitive ELISA. Two Pla a 3 isoforms were identified. Recombinant Pla a 3 showed high purity, structural integrity, IgE-binding capacity comparable to nPla a 3 and biological potency. Sensitization to plane pollen extract was confirmed in 24/25 plane pollen allergics. The frequency of sensitization to Pla a 3 was 53% among patients allergic to both plane pollen and peach and 10% among plane pollen allergics tolerating peach where most patients were sensitized to Pla a 1. Pla a 3 and Pru p 3 showed strong bi-directional IgE cross-reactivity in patients allergic to peach and plane pollen, but not in peach allergics tolerating plane pollen. Levels of IgE-binding were generally higher to Pru p 3 than to Pla a 3. Sensitization to Pla a 3 is relevant in a subgroup of plane pollen allergics with concomitant peach allergy. IgE testing with Pla a 3 may serve as a marker to identify plane pollen allergic patients at risk of LTP-mediated food reactions and thereby improve in vitro diagnostic procedures. © 2016 John Wiley & Sons Ltd.

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

Transparency in stereopsis: parallel encoding of overlapping depth planes.

Science.gov (United States)

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.

Plane-wave least-squares reverse-time migration

KAUST Repository

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

A zonal wavefront sensor with multiple detector planes

Science.gov (United States)

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.

Three-dimensional Frankfort horizontal plane for 3D cephalometry: a comparative assessment of conventional versus novel landmarks and horizontal planes.

Science.gov (United States)

Pittayapat, Pisha; Jacobs, Reinhilde; Bornstein, Michael M; Odri, Guillaume A; Lambrichts, Ivo; Willems, Guy; Politis, Constantinus; Olszewski, Raphael

2018-05-25

To assess the reproducibility of landmarks in three dimensions that determine the Frankfort horizontal plane (FH) as well as two new landmarks, and to evaluate the angular differences of newly introduced planes to the FH. Three-dimensional (3D) surface models were created from CBCT scans of 26 dry human skulls. Porion (Po), orbitale (Or), internal acoustic foramen (IAF), and zygomatico-maxillary suture (ZyMS) were indicated in the software by three observers twice with a 4-week interval. Angles between two FHs (FH 1: Or-R, Or-L, mid-Po; FH 2: Po-R, Po-L, mid-Or) and between FHs and new planes (Plane 1-6) were measured. Coordinates were exported to a spreadsheet. A statistical analysis was performed to define the landmark reproducibility and 3D angles. Intra- and inter-observer landmark reproducibility showed mean difference more than 1 mm for x-coordinates of all landmarks except IAF. IAF showed significantly better reproducibility than other landmarks (P Plane 3, connecting Or-R, Or-L and mid-IAF, and Plane 4, connecting Po-R, Po-L and mid-ZyMS, both showed an angular difference of less than 1 degree when compared to FHs. This study revealed poor reproducibility of the traditional FH landmarks on the x-axis and good reproducibility of a new landmark tested to replace Po, the IAF. Yet, Or showed superior results compared to ZyMS. The potential of using new horizontal planes was demonstrated. Future studies should focus on identification of a valid alternative for Or and ZyMS and on clinical implementation of the findings.

Crystallographic tilt and in-plane anisotropies of an a-plane InGaN/GaN layered structure grown by MOCVD on r-plane sapphire using a ZnO buffer

International Nuclear Information System (INIS)

Liu, H F; Chi, D Z; Liu, W; Guo, S

2016-01-01

High-resolution x-ray diffraction (HRXRD) was used to investigate the crystallographic tilts and structural anisotropies in epitaxial nonpolar a-plane InGaN/GaN grown by metal–organic chemical vapor deposition on r-plane sapphire using a ZnO buffer. The substrate had an unintentional miscut of 0.14° towards its [–4 2 2 3] axis. However, HRXRD revealed a tilt of 0.26° (0.20°) between the ZnO (GaN) (11-20) and the Al 2 O 3 (1-102) atomic planes, with the (11-20) axis of ZnO (GaN) tilted towards its c-axis, which has a difference of 163° in azimuth from that of the substrate’s miscut. Excess broadenings in the GaN/ZnO (11-20) rocking curves (RCs) were observed along its c-axis. Specific analyses revealed that partial dislocations and anisotropic in-plane strains, rather than surface-related effects, wafer curvature or stacking faults, are the dominant factors for the structural anisotropy. The orientation of the partial dislocations is most likely affected by the miscut of the substrate, e.g. via tilting of the misfit dislocation gliding planes created during island coalescences. Their Burgers vector components in the growth direction, in turn, gave rise to crystallographic tilts in the same direction as that of the excess RC-broadenings. (paper)

Crystallographic tilt and in-plane anisotropies of an a-plane InGaN/GaN layered structure grown by MOCVD on r-plane sapphire using a ZnO buffer

Science.gov (United States)

Liu, H. F.; Liu, W.; Guo, S.; Chi, D. Z.

2016-03-01

High-resolution x-ray diffraction (HRXRD) was used to investigate the crystallographic tilts and structural anisotropies in epitaxial nonpolar a-plane InGaN/GaN grown by metal-organic chemical vapor deposition on r-plane sapphire using a ZnO buffer. The substrate had an unintentional miscut of 0.14° towards its [-4 2 2 3] axis. However, HRXRD revealed a tilt of 0.26° (0.20°) between the ZnO (GaN) (11-20) and the Al2O3 (1-102) atomic planes, with the (11-20) axis of ZnO (GaN) tilted towards its c-axis, which has a difference of 163° in azimuth from that of the substrate’s miscut. Excess broadenings in the GaN/ZnO (11-20) rocking curves (RCs) were observed along its c-axis. Specific analyses revealed that partial dislocations and anisotropic in-plane strains, rather than surface-related effects, wafer curvature or stacking faults, are the dominant factors for the structural anisotropy. The orientation of the partial dislocations is most likely affected by the miscut of the substrate, e.g. via tilting of the misfit dislocation gliding planes created during island coalescences. Their Burgers vector components in the growth direction, in turn, gave rise to crystallographic tilts in the same direction as that of the excess RC-broadenings.

Robust micromachining of compliant mechanisms for out-of-plane microsensors

OpenAIRE

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,...

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)

Design and measured performances of a plane reflector augmented box-type solar-energy cooker

International Nuclear Information System (INIS)

Ekechukwu, O.V.

2001-06-01

The design philosophy, construction and measured performances of a plane-reflector augmented box-type solar-energy cooker are presented. The experimental solar cooker consists of an aluminum plate absorber painted matt black and a double-glazed lid. The bottom and sides are lagged with fibreglass wool insulator. The reflector consists of a wooden-framed commercially-available specular plane mirror which is sized to form a cover for the box when not in use. Provision is made for four cooking vessels each capable of holding up to 1 kg of water. Results of thermal performance tests show stagnation absorber plate temperatures of 138 deg. C and 119 deg. C for the cooker with and without the plane reflector in place, respectively. Boiling times of 60 minutes (3600 seconds) and 70 minutes (4200 seconds) for 1 kg of water, for the cooker with and without the reflector in place, respectively, were recorded. The solar cooker performance has been rated using the first figure of merit (F 1 ) on the no-load test and the second figure of merit (F 2 ) on the sensible heat tests. Predicted water boiling times using the two figures of merit compared favourable with measured values. The performance of the cooker with the plane reflector in place was improved tremendously compared to that without the reflector in place. (author)

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

OpenAIRE

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...

An optimized microstructure to minimizing in-plane and through-plane pressure drops of fibrous materials: Counter-intuitive reduction of gas diffusion layer permeability with porosity

Science.gov (United States)

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.

Constructive curves in non-Euclidean planes

OpenAIRE

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.

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.

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.

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)

δ-hydride habit plane determination in α-zirconium by strain energy minimization technique at 25 and 300 deg C

International Nuclear Information System (INIS)

Singh, R.N.; Stahle, P.; Sairam, K.; Ristmana, Matti; Banerjee, S.

2008-01-01

The objective of the present investigation is to predict the habit plane of δ-hydride precipitating in α-Zr at 25 and 300 deg C using strain energy minimization technique. The δ-hydride phase is modeled to undergo isotropic elastic and plastic deformation. The α-Zr phase was modeled to undergo transverse isotropic elastic deformation. Both isotropic plastic and transverse isotropic plastic deformations of α-Zr were considered. Further, both perfect and linear work-hardening plastic behaviors of zirconium and its hydride were considered. Accommodation strain energy of δ-hydrides forming in α-Zr crystal was computed using initial strain method as a function of hydride nuclei orientation. Hydride was modeled as disk with circular edge. The simulation was carried out using materials properties reported at 25 and 300 deg C. Contrary to several habit planes reported in literature for δ-hydrides precipitating in α-Zr crystal the total accommodation energy minima suggests only basal plane i.e. (0001) as the habit plane. (author)

Optically sectioned imaging by oblique plane microscopy

Science.gov (United States)

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.

Occlusal plane location in edentulous patients: a review.

Science.gov (United States)

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.

16-dimensional smooth projective planes with large collineation groups

OpenAIRE

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 ...

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.

Coupled Chiral Structure in Graphene-Based Film for Ultrahigh Thermal Conductivity in Both In-Plane and Through-Plane Directions.

Science.gov (United States)

Meng, Xin; Pan, Hui; Zhu, Chengling; Chen, Zhixin; Lu, Tao; Xu, Da; Li, Yao; Zhu, Shenmin

2018-06-21

The development of high-performance thermal management materials to dissipate excessive heat both in plane and through plane is of special interest to maintain efficient operation and prolong the life of electronic devices. Herein, we designed and constructed a graphene-based composite film, which contains chiral liquid crystals (cellulose nanocrystals, CNCs) inside graphene oxide (GO). The composite film was prepared by annealing and compacting of self-assembled GO-CNC, which contains chiral smectic liquid crystal structures. The helical arranged nanorods of carbonized CNC act as in-plane connections, which bridge neighboring graphene sheets. More interestingly, the chiral structures also act as through-plane connections, which bridge the upper and lower graphene layers. As a result, the graphene-based composite film shows extraordinary thermal conductivity, in both in-plane (1820.4 W m -1 K -1 ) and through-plane (4.596 W m -1 K -1 ) directions. As a thermal management material, the heat dissipation and transportation behaviors of the composite film were investigated using a self-heating system and the results showed that the real-time temperature of the heater covered with the film was 44.5 °C lower than a naked heater. The prepared film shows a much higher efficiency of heat transportation than the commonly used thermal conductive Cu foil. Additionally, this graphene-based composite film exhibits excellent mechanical strength of 31.6 MPa and an electrical conductivity of 667.4 S cm -1 . The strategy reported here may open a new avenue to the development of high-performance thermal management films.

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.

Positivity properties of phase-plane distribution functions

NARCIS (Netherlands)

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

NARCIS (Netherlands)

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

Phase states of a 2D easy-plane ferromagnet with strong inclined anisotropy

International Nuclear Information System (INIS)

Fridman, Yu. A.; Klevets, F. N.; Gorelikov, G. A.; Meleshko, A. G.

2012-01-01

We investigate the spin states of a 2D film exhibiting easy-axis anisotropy and a strong single-ion inclined anisotropy whose axis forms a certain angle with the normal to the film surface. Such a system may have an angular ferromagnetic phase, a spatially inhomogeneous state, and a quadrupole phase, whose realization depends substantially on the inclined anisotropy and the orientation of the wavevector in the film plane.

Simultaneous orthogonal plane imaging.

Science.gov (United States)

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.

Study on the unified constraint parameter for characterizing in-plane and out-of-plane constraint based on the equivalent plastic strain

International Nuclear Information System (INIS)

Yang Jie; Wang Guozhen; Xuan Fuzhen; Tu Shandong

2013-01-01

Background: Constraint can significantly alter the material's fracture toughness. Purpose: In order to increase accuracy of the structural integrity assessment. It needs to consider the effect of constraint on the fracture toughness of nuclear power materials and structures. A unified measure which can reflect both in-plane and out-of-plane constraint is needed. Methods: In this paper, the finite element numerical simulation method was used, a unified measure and characterization parameter of in-plane and out-of-plane constraint based on crack-tip equivalent plastic strain have been investigated. Results: The results show that the area surrounded by ε p isoline has a good relevance with the material's fracture toughness on different constraint conditions, so it may be a suitable parameter. Based on the area A PEEQ , a unified constraint characterization parameter √A p is defined. It was found that there exists a sole linear relation between the normalized fracture toughness J IC /J re f and √A p regardless of the in-plane, out-of-plane constraint and the selection of the p isolines. The sole J IC /J re f-√A p line exists for a certain material. For different materials, the slope of J IC /J re f-√A p reference line is different. The material whose slope is larger has a higher J IC /J re f and is more sensitive to constraint at the same magnitude of normalized unified parameter. Conclusions: The unified J IC /J re f -√A p reference line may be used to assess the safety of a cracked component with any constraint levels regardless of in-plane or out-of-plane constraint or both. (authors)

The Curious Out-of-Plane Conductivity of PEDOT : PSS

NARCIS (Netherlands)

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

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.

Testing of focal plane arrays

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

Experimental investigation on in-plane/out-of-plane vortex-induced vibrations of curved cylinder in parallel and perpendicular flows

Science.gov (United States)

Srinil, Narakorn; Ma, Bowen; Zhang, Licong

2018-05-01

This study is motivated by an industrial need to better understand the vortex-induced vibration (VIV) of a curved structure subject to current flows with varying directions whose data for model calibration and validation are lacking. In this paper, new experimental investigations on the two-degree-of-freedom in-plane/out-of-plane VIV of a rigid curved circular cylinder immersed in steady and uniform free-stream flows are presented. The principal objective is to examine how the approaching flow direction versus the cylinder curvature plane affects cross-flow and in-line VIV and the associated hydrodynamic properties. This is achieved by testing the curved cylinder in 3 different flow orientations comprising the parallel flows aligned with the curvature vertical plane in convex and concave configurations, and the flows perpendicular to the curvature plane. The case of varying flow velocities in a subcritical flow range with a maximum Reynolds number of about 50,000 is considered for the curved cylinder with a low mass ratio and damping ratio. Experimental results are presented and discussed in terms of the cylinder response amplitudes, inclination angles, mean displacements, motion trajectories, oscillation frequencies, hydrodynamic forces, relative phases, fluid excitation and added inertia coefficients. Comparisons with other experimental results of curved and straight cylinder VIV are also presented. The experiments highlight the important effects of cylinder curvature versus flow orientation on the combined cross-flow/in-line VIV. The maximum (minimum) responses occur in the perpendicular (convex) flow case whereas the extended lower-branch responses occur in the concave flow case. For perpendicular flows, some meaningful features are observed, including the appearances of cross-flow mean displacements and asymmetric eight-shaped motion trajectories due to multiple 2:1:1 resonances where two out-of-plane and one in-plane dominant frequencies are simultaneously

The plane elasticity problem for a crack near the curved surface

Science.gov (United States)

Lebedeva, M. V.

2018-05-01

The unconventional approach to the plane elasticity problem for a crack near the curved surface is presented. The solution of the problem is considered in the form of the sum of solutions of two auxiliary problems. The first one describes the plane with a crack, whose surfaces are loaded by some unknown self-balanced force p(x). The second problem is dealing with the semi-infinite region with the boundary conditions equal to the difference of boundary conditions of the problem to be sought and the solution of the first problem on the region border. The unknown function p(x) is supposed to be approximated with the sufficient level of accuracy by N order polynomial with complex coefficients. This paper is aimed to determine the critical loads causing the spontaneous growth of cracks. The angles of propagation of the stationary cracks located in the region with a ledge or a cut are found. The influence of length of a crack on the bearing ability of an elastic body with the curved surface is investigated. The effect of a form of the concentrator and orientation of a crack to the fracture load subject to the different combinations of forces acting both on a surface of a crack and at infinity is analysed. The results of this research can be applied for calculation of the durability of thin-walled vessels of pressure, e.g., chemical reactors, in order to ensure their ecological safety.

Problems in the theory of modular forms

CERN Document Server

Murty, M Ram; Graves, Hester

2016-01-01

This book introduces the reader to the fascinating world of modular forms through a problem-solving approach. As such, besides researchers, the book can be used by the undergraduate and graduate students for self-instruction. The topics covered include q-series, the modular group, the upper half-plane, modular forms of level one and higher level, the Ramanujan τ-function, the Petersson inner product, Hecke operators, Dirichlet series attached to modular forms and further special topics. It can be viewed as a gentle introduction for a deeper study of the subject. Thus, it is ideal for non-experts seeking an entry into the field. .

On Finite Hjelmslev Planes of Parameters (pk−1, p)

OpenAIRE

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.

Two-transitive MInkowski planes

NARCIS (Netherlands)

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.

ARC Code TI: X-Plane Communications Toolbox (XPC)

Data.gov (United States)

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...

Evaluation of Forming Limit by the 3 Dimensional Local Bifurcation Theory

International Nuclear Information System (INIS)

Nishimura, Ryuichi; Nakazawa, Yoshiaki; Ito, Koichi; Uemura, Gen; Mori, Naomichi

2007-01-01

A theoretical prediction and evaluation method for the sheet metal formability is developed on the basis of the three-dimensional local bifurcation theory previously proposed by authors. The forming limit diagram represented on the plane defined by the ratio of stress component to work-hardening rate is perfectly independent of plastic strain history. The upper and the lower limit of the sheet formability are indicated by the 3D critical line and the Stoeren-Rice's critical line on this plane, respectively. In order to verify the above mentioned behavior of the proposed forming limit diagram, the experimental research is also conducted. From the standpoint of the mechanical instability theory, a new concept called instability factor is introduced. It represents a degree of acceleration by current stress for developing the local bifurcation mode toward a fracture. The instability factor provides a method to evaluate a forming allowance which is useful to appropriate identification for a forming limit and to optimize the forming condition. The proposed criterion provides not only the moment to initiate the necking but also the local bifurcation mode vector and the direction of necking line

Instabilities of Kirkendall planes

NARCIS (Netherlands)

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.

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)

Application of invariant plane strain (IPS) theory to γ hydride formation in dilute Zr-Nb alloys

International Nuclear Information System (INIS)

Srivastava, D.; Neogy, S.; Dey, G.K.; Banerjee, S.; Ranganathan, S.

2005-01-01

The crystallographic aspects associated with the formation of the γ hydride phase (fct) from the α (hcp) phase and the β (bcc) phase in Zr-Nb alloys have been studied in two distinct situations, viz., in the α matrix in pure Zr and Zr-2.5Nb and in the β matrix in β stabilized Zr-20Nb alloy. The β-γ formation can be treated primarily as a simple shear on the basal plane involving a change in the stacking sequence. A possible mechanism for α-γ transformation has been presented in this paper. In this paper the β->γ transformation has been considered in terms of the invariant plane strain theory (IPS) in order to predict the crystallographic features of the γ hydride formed. The lattice invariant shear (LIS) (110) β [1-bar 10] β ||(111) γ [12-bar 1] γ has been considered and the crystallographic parameters associated with bcc->fct transformation, such as the habit plane and the magnitude of the LIS and the shape strain have been computed. The predictions made in the present analysis have been compared with experimentally observed habit planes. The α/γ and β/γ interface has been examined by high resolution transmission electron microscopy (HRTEM) technique to compare with the interfaces observed in martensitic transformations

DLCQ and plane wave matrix Big Bang models

Science.gov (United States)

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.

Flights of a spacecraft with a solar sail out of ecliptic plane

Science.gov (United States)

Polyakhova, Elena; Starkov, Vladimir; Stepenko, Nikolai

2018-05-01

Solar sailing is an unique form of spacecraft (SC) propulsion that uses the free and limitless supply of photons from the Sun. The investigation of near-the-Sun space properties is of the great scientific interest. It can be realized by help of solar sailing. We present the numerical simulation of several closed modelled trajectories of a spacecraft with a controlled solar sail to reach out of ecliptic plane, to flight over the Sun north and south poles and return to the Earth.

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

Angle measures, general rotations, and roulettes in normed planes

Science.gov (United States)

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.

Vacuum Predisperser For A Large Plane-Grating Spectrograph

Science.gov (United States)

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.

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.)

Quantitative compositional analysis and field-evaporation behavior of ordered Ni4Mo on an atomic plane-by-plane basis: an atom-probe field-ion microscope study. MSC report No. 4802

International Nuclear Information System (INIS)

Yamamoto, M.; Seidman, D.N.

1982-10-01

The (211) fundamental and (101) superlattice planes, of the bct lattice, were analysed chemically on an atomic plane-by-plane basis. It was demonstrated that the composition of each individual plane can be determined as a function of depth without any ambiguity. The overall average Mo concentration was measured to be 17.1 at. % for the (211) fundamental plane. Details of the field evaporation behavior of the (211) fundamental and (101) superlattice planes were studied. The field-evaporation behavior is described in terms of the field-evaporation rate, the order of the field evaporated ions, etc. Each individual atomic plane field evaporated on an atomic plane-by-plane basis for the (211) fundamental plane. While for (101) superlattice plane a group of planes consisting of one plane of Mo atoms and four planes of Ni atoms field-evaporated as a unit. An abnormal increase in the number of Mo atoms was found in the central portion of the (211) fundamental plane. Possible mechanisms for the abnormal field evaporation rate are discussed. It is concluded that the atom probe technique can be used to follow the physics and chemistry of the field-evaporation process and the chemistry of the alloy as a function of position, on a subnanometer scale, throughout the specimen. 13 figures

On the smoothness of electric fields near plane gratings of cylindrical conductors

Energy Technology Data Exchange (ETDEWEB)

Judd, D.L. [Lawrence Berkeley Lab., CA (United States)

1995-02-01

The electric field near an infinite plane grating of equally spaced round rods at the same potential, forming the boundary of a uniform field, is determined analytically to good accuracy by conformal transformations and evaluated numerically. This contribution, which has a frankly pedagogical flavor, to the Klaus Halbach Festschrift is offered to honor his displayed mastery of conformal techniques. Although the numerical work and the form of its presentation are new, the transformation used is not original. However, to locate its antecedents in an archival journal it was necessary to seek out a paper published in 1923 (close to the year of his birth, and of mine), in a place obscure to modern physicists, so the authors efforts cannot be said to replicate recent published work. A new insight is obtained in the form of a simple estimate of departures from field uniformity at all distances from rods of any size.

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...

Basic examination of in-plane spatial resolution in multi-slice CT

International Nuclear Information System (INIS)

Hara, Takanori; Kato, Hideki; Akiyama, Mitsutoshi; Murata, Katsutoshi

2002-01-01

In computed tomography (single-slice spiral CT, conventional CT), in-plane (x-y plane) spatial resolution is consistently identified as depending on the detector density of the in-plane (x-y plane). However, we considered that the in-plane (x-y plane) spatial resolution of multi-slice CT (MSCT) was influenced by an error in the detector's sensitivity to the Z-axis and by the frequency of use of direct row data and complementary row data when the image of spiral pitches (SP) was reconstructed. Our goal in this experiment was to analyze the relationship of the in-plane (x-y plane) spatial resolution of an asymmetric-type detector in MSCT to SP, tube current, and rotation time. By employing a tungsten wire phantom of 0.2 mm in diameter, we examined modulation transfer functions (MTF) by point-spread functions (PSF) of CT-images. Next, using the mean-square-root bandwidth theory, we analyzed the MTF of wire phantoms. The analysis of in-plane (x-y plane) spatial resolution revealed that various tube currents had no effect on the value of the mean-square-root bandwidth. However, rotation time and high spiral pitch did have an effect on mean-square-root bandwidth. Considering the results mentioned above, spiral pitch (z-axis reconstruction algorithm) had a slight effect on in-plane (x-y plane) spatial resolution of asymmetric-type detectors in MSCT. Accordingly, we proposed a new general view of VDDz (view/mm) in MSCT that considered view data density on the Z-axis according to spiral pitch (mm/rotation), rotation time (view/rotation), and slice collimation. (author)

Discretization of superintegrable systems on a plane

Science.gov (United States)

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

Science.gov (United States)

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…

Quantum group and Manin plane related to a coloured braid group representation

International Nuclear Information System (INIS)

Basu Mallick, B.

1993-07-01

By considering 'coloured' braid group representation we have obtained a quantum group, which reduces to the standards GL q (2) and GL pq (2) cases at some particular limits of the 'colour' parameters. In spite of quite complicated nature, all of these new quantum group relations can be expressed neatly in the Heisenberg-Weyl form, for a nontrivial choice of the basis elements. Furthermore, it is possible to associate invariant Manin planes, parametrized by the 'colour' variables, with such quantum group structure. (author). 26 refs

Multispectral linear array (MLA) focal plane mechanical and thermal design

Science.gov (United States)

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.

Focal plane array with modular pixel array components for scalability

Science.gov (United States)

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.

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.)

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.

Towards the design of a RF-harvesting EBG ground plane

NARCIS (Netherlands)

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

47 CFR 73.160 - Vertical plane radiation characteristics, f(θ).

Science.gov (United States)

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...

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.

BKP plane partitions

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

BKP plane partitions

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.

Using a Borated Panel to Form a Dual Neutron-Gamma Detector

Energy Technology Data Exchange (ETDEWEB)

Scott Wilde; Raymond Keegan

2008-06-20

A borated polyethylene plane placed between a neutron source and a gamma spectrometer is used to form a dual neutron-gamma detection system. The polyethylene thermalizes the source neutrons so that they are captured by {sup 10}B to produce a flux of 478 keV gamma-rays that radiate from the plane. This results in a buildup of count rate in the detector over that from a disk of the same diameter as the detector crystal (same thickness as the panel). Radiation portal systems are a potential application of this technique.

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

Long-range current flow and percolation in Rabbits-type conductors and the relative importance of out-of-plane and in-plane mis orientations in determining J {sub c}

Energy Technology Data Exchange (ETDEWEB)

Goyal, A. [Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6116 (United States)]. E-mail: goyala@ornl.gov; Rutter, N. [Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6116 (United States); University of Cambridge, Pembroke St., Cambridge CB2 3QZ (United Kingdom); Cantoni, C. [Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6116 (United States); Lee, D.F. [Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6116 (United States)

2005-10-01

Calculations of long-range current flow using an advanced percolation model show that with the presently observed texture in RABiTS substrates, the dependence of J {sub c} on length as a function of width is greatly reduced. Furthermore, this dependence becomes almost negligible in applied fields. These results suggest that sub-division of a wide conductor into narrow filaments should be possible without loss in J {sub c}. The relative importance of the out-of-plane texture in affecting intergranular J {sub c} was also explored by fabricating RABiTS substrates with different out-of-plane textures but approximately the same in-plane texture. This was accomplished by using TiN as a seed layer for which significant sharpening of the out-of-plane texture is observed. Similar J {sub c} was found for samples with differing out-of-plane texture but almost the same in-plane texture. Finally, separation of the total misorientation in GB networks into in-plane and out-of-plane misorientations using manipulations in Rodrigues space shows that J {sub c} correlates best with in-plane texture.

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

Science.gov (United States)

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.

Electrodynamics, Differential Forms and the Method of Images

Science.gov (United States)

Low, Robert J.

2011-01-01

This paper gives a brief description of how Maxwell's equations are expressed in the language of differential forms and use this to provide an elegant demonstration of how the method of images (well known in electrostatics) also works for electrodynamics in the presence of an infinite plane conducting boundary. The paper should be accessible to an…

Hot forming of composite prepreg: Numerical analyses

Science.gov (United States)

Guzman-Maldonado, Eduardo; Hamila, Nahiène; Boisse, Philippe; El Azzouzi, Khalid; Tardif, Xavier; Moro, Tanguy; Chatel, Sylvain; Fideu, Paulin

2017-10-01

The work presented here is part of the "FORBANS" project about the Hot Drape Forming (HDF) process consisting of unidirectional prepregs laminates. To ensure a fine comprehension of this process a combination strategy between experiment and numerical analysis is adopted. This paper is focused on the numerical analysis using the finite element method (FEM) with a hyperelastic constitutive law. Each prepreg layer is modelled by shell elements. These elements consider the tension, in-plane shear and bending behaviour of the ply at different temperatures. The contact/friction during the forming process is taken into account using forward increment Lagrange multipliers.

TECHNIQUE OF TESTING ON FRETTING AT THE SPHERE-TO-PLANE CONTACT

Directory of Open Access Journals (Sweden)

А. Khimko

2012-12-01

Full Text Available  The methodology of conducting tests on fretting at the sphere-to-plane contact was developed for the wing mechanization unit, namely for screw-nut pair with intermediate balls. Wearability tests were conducted on a modified installation МФК-1, the feature of which is the designed holder that allows testing with real balls. It was found that at the dry contact of ШХ-15 and 30Х2НВФA materials, surface microcracks are formed due to welding of microasperities areas and their rupture under the influence of vibration.

Surface anatomy and anatomical planes in the adult turkish population.

Science.gov (United States)

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.

Application of invariant plane strain (IPS) theory to {gamma} hydride formation in dilute Zr-Nb alloys

Energy Technology Data Exchange (ETDEWEB)

Srivastava, D. [Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra (India)]. E-mail: dsrivastavabarc@yahoo.co.in; Neogy, S. [Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra (India); Dey, G.K. [Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra (India); Banerjee, S. [Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra (India); Ranganathan, S. [Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra (India)

2005-04-25

The crystallographic aspects associated with the formation of the {gamma} hydride phase (fct) from the {alpha} (hcp) phase and the {beta} (bcc) phase in Zr-Nb alloys have been studied in two distinct situations, viz., in the {alpha} matrix in pure Zr and Zr-2.5Nb and in the {beta} matrix in {beta} stabilized Zr-20Nb alloy. The {beta}-{gamma} formation can be treated primarily as a simple shear on the basal plane involving a change in the stacking sequence. A possible mechanism for {alpha}-{gamma} transformation has been presented in this paper. In this paper the {beta}->{gamma} transformation has been considered in terms of the invariant plane strain theory (IPS) in order to predict the crystallographic features of the {gamma} hydride formed. The lattice invariant shear (LIS) (110){sub {beta}}[1-bar 10]{sub {beta}}||(111){sub {gamma}}[12-bar 1]{sub {gamma}} has been considered and the crystallographic parameters associated with bcc->fct transformation, such as the habit plane and the magnitude of the LIS and the shape strain have been computed. The predictions made in the present analysis have been compared with experimentally observed habit planes. The {alpha}/{gamma} and {beta}/{gamma} interface has been examined by high resolution transmission electron microscopy (HRTEM) technique to compare with the interfaces observed in martensitic transformations.

Wavefront propagation from one plane to another with the use of Zernike polynomials and Taylor monomials.

Science.gov (United States)

Dai, Guang-ming; Campbell, Charles E; Chen, Li; Zhao, Huawei; Chernyak, Dimitri

2009-01-20

In wavefront-driven vision correction, ocular aberrations are often measured on the pupil plane and the correction is applied on a different plane. The problem with this practice is that any changes undergone by the wavefront as it propagates between planes are not currently included in devising customized vision correction. With some valid approximations, we have developed an analytical foundation based on geometric optics in which Zernike polynomials are used to characterize the propagation of the wavefront from one plane to another. Both the boundary and the magnitude of the wavefront change after the propagation. Taylor monomials were used to realize the propagation because of their simple form for this purpose. The method we developed to identify changes in low-order aberrations was verified with the classical vertex correction formula. The method we developed to identify changes in high-order aberrations was verified with ZEMAX ray-tracing software. Although the method may not be valid for highly irregular wavefronts and it was only proven for wavefronts with low-order or high-order aberrations, our analysis showed that changes in the propagating wavefront are significant and should, therefore, be included in calculating vision correction. This new approach could be of major significance in calculating wavefront-driven vision correction whether by refractive surgery, contact lenses, intraocular lenses, or spectacles.

Comparing trapezius muscle activity in the different planes of shoulder elevation.

Science.gov (United States)

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.

Development and construction of a focal-plane detector for the Munich Q3D spectrograph

International Nuclear Information System (INIS)

Lindner, H.

1989-01-01

For the Munich Q3D magnet spectrograph a focal-plane detector was developed, constructed, and taken in operation. It is primary layed out for light ions like p, d, t 3 He, and 4 He, but can be also applied for heavy ions. The position resolution amounts to about 0.1 mm at counting rates of about 10 kHz. In the detector filled with counting gas on anode wires along the focal plane charge avalanches are formed, which influence in several neighbouring cathode stripes of the dimension (3x25) mm 2 signals. These signals are singularily read out and digitized, i.e. to each of the at the whole 114 cathode strips is assigned an own preamplifier, puls shaper, peak detector, and analog-to-digital converter (ADC). After the digitization in a hardware-like constructed calculator unit the center of mass of the charge distribution influenced by the charge avalanche is calculated, the position of the incident particle is obtained. The detector yields beyond the position signal yet also a signal ΔE form the anode wires, which gives the energy loss of the particle in the gas space, as well as a residual-energy signal E rest from a scintillator, in which the particles are stopped. By this the radiation background (γ's and n) can be separated very well from the required particles. With the focal-plane detector the 103 Rh(d, p) 104 Rh transfer reaction was measured at three different spectrograph angles. The measured level energies and angular momentum transfers are compared with (n, γ) data and discussed. (orig.) [de

The Off-plane Grating Rocket Experiment

Science.gov (United States)

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.

THE BOLOCAM GALACTIC PLANE SURVEY. III. CHARACTERIZING PHYSICAL PROPERTIES OF MASSIVE STAR-FORMING REGIONS IN THE GEMINI OB1 MOLECULAR CLOUD

International Nuclear Information System (INIS)

Dunham, Miranda K.; Evans, Neal J.; Harvey, Paul; Merello, Manuel; Rosolowsky, Erik; Cyganowski, Claudia J.; Aguirre, James; Bally, John; Battersby, Cara; Ginsburg, Adam; Glenn, Jason; Stringfellow, Guy S.; Bradley, Eric Todd; Dowell, Darren; Drosback, Meredith; Schlingman, Wayne; Shirley, Yancy L.; Walawender, Josh; Williams, Jonathan P.

2010-01-01

We present the 1.1 mm Bolocam Galactic Plane Survey (BGPS) observations of the Gemini OB1 molecular cloud complex, and targeted NH 3 observations of the BGPS sources. When paired with molecular spectroscopy of a dense gas tracer, millimeter observations yield physical properties such as masses, radii, mean densities, kinetic temperatures, and line widths. We detect 34 distinct BGPS sources above 5σ = 0.37 Jy beam -1 with corresponding 5σ detections in the NH 3 (1,1) transition. Eight of the objects show water maser emission (20%). We find a mean millimeter source FWHM of 1.12 pc and a mean gas kinetic temperature of 20 K for the sample of 34 BGPS sources with detections in the NH 3 (1,1) line. The observed NH 3 line widths are dominated by non-thermal motions, typically found to be a few times the thermal sound speed expected for the derived kinetic temperature. We calculate the mass for each source from the millimeter flux assuming the sources are isothermal and find a mean isothermal mass within a 120'' aperture of 230 ± 180 M sun . We find a total mass of 8400 M sun for all BGPS sources in the Gemini OB1 molecular cloud, representing 6.5% of the cloud mass. By comparing the millimeter isothermal mass to the virial mass calculated from the NH 3 line widths within a radius equal to the millimeter source size, we find a mean virial parameter (M vir /M iso ) of 1.0 ± 0.9 for the sample. We find mean values for the distributions of column densities of 1.0 x 10 22 cm -2 for H 2 , and 3.0 x 10 14 cm -2 for NH 3 , giving a mean NH 3 abundance of 3.0 x 10 -8 relative to H 2 . We find volume-averaged densities on the order of 10 3 -10 4 cm -3 . The sizes and densities suggest that in the Gem OB1 region the BGPS is detecting the clumps from which stellar clusters form, rather than smaller, higher density cores where single stars or small multiple systems form.

Pulmonary intersegmental planes: imaging appearance and possible reasons leading to their visualization.

Science.gov (United States)

Zuo, Yi-Zhi; Liu, Chao; Liu, Shu-Wei

2013-04-01

To describe the normal imaging appearance of pulmonary intersegmental planes on thoracic computed tomographic (CT) scans and determine the possible reasons related to their visualization in terms of aging and anatomy. The study was approved by the internal ethics review board. Informed consent was obtained. A retrospective review was undertaken of 104 thoracic multidetector CT scans of an older group (>65 years) and younger group (planes were assessed. Group comparisons were made, and linear regression analysis was used to assess relationships between age and visualization of intersegmental planes. Thirty lung samples (10 × 10 × 10 mm(3)) from autopsy were scanned by using micro-CT. Thicknesses of intersegmental planes were measured. Significant differences of the thickness between visible and invisible intersegmental planes were assessed with the independent t test. In five fetal specimens (17-21 weeks in gestational age), 7.0-T magnetic resonance (MR) imaging was performed to determine the congenital difference of thickness of intersegmental planes. Within the right lung, appearance rates of visible intersegmental planes were 71.2% at S1-S3, 54.8% at S4-S5, and 70.2% at S7-S10. Within the left lung, appearance rates of visible intersegmental planes were 39.4% at S1+2 to S3, 64.4% at S4-S5, 18.3% at S7-S8, and 89.4% at S7-S10. Appearance rates of visible intersegmental planes on thoracic CT scans were not significantly different (P ≥ .38) between younger and older groups. Mean thicknesses of visible and invisible intersegmental planes were 681.3 μm ± 75.3 (standard deviation) and 221.7 μm ± 54.1, respectively. Visible intersegmental planes were significantly thicker than invisible intersegmental planes (P planes were also seen on fetal lung 7.0-T MR images. The thickness of pulmonary intersegmental planes and variation of intersegmental veins were closely related to visualization of intersegmental planes on thoracic CT scans. Aging was excluded as the

The OBS control plane

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...

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

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)

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

Development of an in-plane biaxial test for forming limit curve (FLC) characterization of metallic sheets

International Nuclear Information System (INIS)

Zidane, I; Guines, D; Léotoing, L; Ragneau, E

2010-01-01

The main objective of this work is to propose a new experimental device able to give for a single specimen a good prediction of rheological parameters and formability under static and dynamic conditions (for intermediate strain rates). In this paper, we focus on the characterization of sheet metal forming. The proposed device is a servo-hydraulic testing machine provided with four independent dynamic actuators allowing biaxial tensile tests on cruciform specimens. The formability is evaluated thanks to the classical forming limit diagram (FLD), and one of the difficulties of this study was the design of a dedicated specimen for which the necking phenomenon appears in its central zone. If necking is located in the central zone of the specimen, then the speed ratio between the two axes controls the strain path in this zone and a whole forming limit curve can be covered. Such a specimen is proposed through a numerical and experimental validation procedure. A rigorous procedure for the detection of numerical and experimental forming strains is also presented. Finally, an experimental forming limit curve is determined and validated for an aluminium alloy dedicated to the sheet forming processes (AA5086)

A study of parallelism of the occlusal plane and ala-tragus line.

Science.gov (United States)

Sadr, Katayoun; Sadr, Makan

2009-01-01

Orientation of the occlusal plane is one of the most important clinical procedures in prostho-dontic rehabilitation of edentulous patients. The aim of this study was to define the best posterior reference point of ala-tragus line for orientation of occlusal plane for complete denture fabrication. Fifty-three dental students (27 females and 26 males) with complete natural dentition and Angel's Class I occlusal relationship were selected. The subjects were photographed in natural head position while clenching on a Fox plane. After tracing the photographs, the angles between the following lines were measured: the occlusal plane (Fox plane) and the superior border of ala-tragus, the occlusal plane (Fox plane) and the middle of ala-tragus as well as the occlusal plane (Fox plane) and the inferior border of ala-tragus. Descriptive statistics, one sample t-test and independent t-test were used. P value less than 0.05 was considered significant. There was no parallelism between the occlusal plane and ala-tragus line with three different posterior ends and one sample t-test showed that the angles between them were significantly different from zero (pplane. The superior border of the tragus is suggested as the posterior reference for ala-tragus line.

Mechanical properties of novel forms of graphyne under strain: A density functional theory study

Science.gov (United States)

Majidi, Roya

2017-06-01

The mechanical properties of two forms of graphyne sheets named α-graphyne and α2-graphyne under uniaxial and biaxial strains were studied. In-plane stiffness, bulk modulus, and shear modulus were calculated based on density functional theory. The in-plane stiffness, bulk modulus, and shear modulus of α2-graphyne were found to be larger than that of α-graphyne. The maximum values of supported uniaxial and biaxial strains before failure were determined. The α-graphyne was entered into the plastic region with the higher magnitude of tension in comparison to α2-graphyne. The mechanical properties of α-graphyne family revealed that these forms of graphyne are proper materials for use in nanomechanical applications.

Plane Transformations in a Complex Setting III: Similarities

Science.gov (United States)

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…

The Fermionic Signature Operator and Hadamard States in the Presence of a Plane Electromagnetic Wave

Science.gov (United States)

Finster, Felix; Reintjes, Moritz

2017-05-01

We give a non-perturbative construction of a distinguished state for the quantized Dirac field in Minkowski space in the presence of a time-dependent external field of the form of a plane electromagnetic wave. By explicit computation of the fermionic signature operator, it is shown that the Dirac operator has the strong mass oscillation property. We prove that the resulting fermionic projector state is a Hadamard state.

C-plane Reconstructions from Sheaf Acquisition for Ultrasound Electrode Vibration Elastography.

Science.gov (United States)

Ingle, Atul; Varghese, Tomy

2014-09-03

This paper presents a novel algorithm for reconstructing and visualizing ablated volumes using radiofrequency ultrasound echo data acquired with the electrode vibration elastography approach. The ablation needle is vibrated using an actuator to generate shear wave pulses that are tracked in the ultrasound image plane at different locations away from the needle. This data is used for reconstructing shear wave velocity maps for each imaging plane. A C-plane reconstruction algorithm is proposed which estimates shear wave velocity values on a collection of transverse planes that are perpendicular to the imaging planes. The algorithm utilizes shear wave velocity maps from different imaging planes that share a common axis of intersection. These C-planes can be used to generate a 3D visualization of the ablated region. Experimental validation of this approach was carried out using data from a tissue mimicking phantom. The shear wave velocity estimates were within 20% of those obtained from a clinical scanner, and a contrast of over 4 dB was obtained between the stiff and soft regions of the phantom.

Mechanical design aspects of a soft X-ray plane grating monochromator

CERN Document Server

Vasina, R; Dolezel, P; Mynar, M; Vondracek, M; Chab, V; Slezak, J A; Comicioli, C; Prince, K C

2001-01-01

A plane grating monochromator based on the SX-700 concept has been constructed for the Materials Science Beamline, Elettra, which is attached to a bending magnet. The tuning range is from 35 to 800 eV with calculated spectral resolving power epsilon/DELTA epsilon better than 4000 in the whole range. The optical elements consist of a toroidal prefocusing mirror, polarization aperture, entrance slit, plane pre-mirror, single plane grating (blazed), spherical mirror, exit slit and toroidal refocusing mirror. The plane grating is operated in the fixed focus mode with C sub f sub f =2.4. Energy scanning is performed by rotation of the plane grating and simultaneous translation and rotation of the plane pre-mirror. A novel solution is applied for the motion of the plane pre-mirror, namely by a translation and mechanically coupling the rotation by a cam. The slits have no moving parts in vacuum to reduce cost and increase ruggedness, and can be fully closed without risk of damage. In the first tests, a resolving pow...

A study on the central plane of image layer in panoramic radiograph

International Nuclear Information System (INIS)

Lee, Moon Bai; Park, Chang Seo

1986-01-01

The purpose of this investigation was to locate the plane of the image layer on the panoramic machine relative to a specific point on the machine. In the study of the central plane of the image layer of panoramic radiograph, using the Morrita Company PANEX-EC a series of 33 exposures were taken with the 4-5 experimental pins placed in the holes of the plastic model plate, then evaluated by human eye. The author analyzed the central plane of the image layer by Mitutoy-A-221 and calculated horizontal and vertical magnification ratio in central plane of the image layer determined experimentally. The results were as follows: 1. The location of the central plane of the image layer determined experimentally was to lateral compared with manufactural central plane. 2. Horizontal magnification ratio in the central plane of image layer determined experimentally was 9.25%. 3. Vertical magnification ratio in the central plane of the image layer determined experimentally was 9.17%.

Jet-hadron correlations relative to the event plane at the LHC with ALICE

Science.gov (United States)

Mazer, Joel; Alice Collaboration

2017-11-01

In ultra relativistic heavy-ion collisions at the Large Hadron Collider (LHC), conditions are met to produce a hot, dense and strongly interacting medium known as the Quark Gluon Plasma (QGP). Quarks and gluons from incoming nuclei collide to produce partons at high momenta early in the collisions. By fragmenting into collimated sprays of hadrons, these partons form 'jets'. The outgoing partons scatter and interact with the medium, leading to a manifestation of medium modifications of jets in the final state, known as jet quenching. Within the framework of perturbative QCD, jet production is well understood in pp collisions. We use jets measured in pp interactions as a baseline reference for comparing to heavy-ion collision systems to detect and study jet quenching. The jet quenching mechanism can be studied through the angular correlations of jets with charged hadrons and is examined in transverse momentum (pT) bins of the jets, pT bins of the associated hadrons, and as a function of collision centrality. A robust and precise background subtraction method is used in this analysis to remove the complex, flow dominated, heavy-ion background. The analysis of angular correlations for different orientations of the jet relative to the event plane allows for the study of the path-length dependence of medium modifications to jets. The event plane dependence of azimuthal angular correlations of charged hadrons with respect to the axis of an R = 0.2 reconstructed full (charged + neutral) jet in Pb-Pb collisions at √{sNN} = 2.76 TeV in ALICE is presented. Results are compared for three angular bins of the jet relative to the event plane in mid-peripheral events. The yields relative to the event plane are presented and then quantified through yield ratio calculations. The results show no significant path-length dependence on the medium modifications.

Comparative Evaluation of Topical 10% Potassium Hydroxide and 30% Trichloroacetic Acid in the Treatment of Plane Warts.

Science.gov (United States)

Jayaprasad, Sandhaya; Subramaniyan, Radhakrishnan; Devgan, Shalini

2016-01-01

Warts are benign proliferations of skin and mucosa caused by the human papillomavirus (HPV). Plane warts are caused by HPV types 3, 10, 28, and 41, occurring mostly in children and young adults. Among the treatment modalities, topical application of trichloroacetic acid (TCA) is age old. Potassium hydroxide (KOH) has a keratolytic effect on virus-infected cells. It is less irritating, less painful, less scar forming, and can be safely used in children too. Hence, it could be a better topical agent in the treatment of plane warts. To compare the safety and efficacy of topical 10% KOH with 30% TCA in the treatment of plane warts. Sixty consecutive patients with plane warts were randomly assigned into two arms of thirty patients each; arm A received topical 10% KOH and arm B received topical 30% TCA as a once weekly application until the complete clearance of warts or a maximum period of 12 weeks. Statistically no significant difference ( P = 0.07) was found between the objective therapeutic response to 10% KOH and 30% TCA at the end of study (12 weeks). However, subjective response to 10% KOH was better and statistically significant ( P = 0.03). There was no recurrence of warts seen on follow-up for 3 months of complete responders in both the arms. 10% KOH is found to be equally effective in the treatment of plane warts compared to 30% TCA with the advantage of faster onset of action and tendency of completely clearing warts with fewer side effects.

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.)

Polarization sensitivity testing of off-plane reflection gratings

Science.gov (United States)

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.

Statistical framework for the utilization of simultaneous pupil plane and focal plane telemetry for exoplanet imaging. I. Accounting for aberrations in multiple planes.

Science.gov (United States)

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.

High-quality nonpolar a-plane GaN epitaxial films grown on r-plane sapphire substrates by the combination of pulsed laser deposition and metal–organic chemical vapor deposition

Science.gov (United States)

Yang, Weijia; Zhang, Zichen; Wang, Wenliang; Zheng, Yulin; Wang, Haiyan; Li, Guoqiang

2018-05-01

High-quality a-plane GaN epitaxial films have been grown on r-plane sapphire substrates by the combination of pulsed laser deposition (PLD) and metal–organic chemical vapor deposition (MOCVD). PLD is employed to epitaxial growth of a-plane GaN templates on r-plane sapphire substrates, and then MOCVD is used. The nonpolar a-plane GaN epitaxial films with relatively small thickness (2.9 µm) show high quality, with the full-width at half-maximum values of GaN(11\\bar{2}0) along [1\\bar{1}00] direction and GaN(10\\bar{1}1) of 0.11 and 0.30°, and a root-mean-square surface roughness of 1.7 nm. This result is equivalent to the quality of the films grown by MOCVD with a thickness of 10 µm. This work provides a new and effective approach for achieving high-quality nonpolar a-plane GaN epitaxial films on r-plane sapphire substrates.

Linearized motion estimation for articulated planes.

Science.gov (United States)

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.

Large In-Plane and Vertical Piezoelectricity in Janus Transition Metal Dichalchogenides.

Science.gov (United States)

Dong, Liang; Lou, Jun; Shenoy, Vivek B

2017-08-22

Piezoelectricity in 2D van der Waals materials has received considerable interest because of potential applications in nanoscale energy harvesting, sensors, and actuators. However, in all the systems studied to date, strain and electric polarization are confined to the basal plane, limiting the operation of piezoelectric devices. In this paper, based on ab initio calculations, we report a 2D materials system, namely, the recently synthesized Janus MXY (M = Mo or W, X/Y = S, Se, or Te) monolayer and multilayer structures, with large out-of-plane piezoelectric polarization. For MXY monolayers, both strong in-plane and much weaker out-of-plane piezoelectric polarizations can be induced by a uniaxial strain in the basal plane. For multilayer MXY, we obtain a very strong out-of-plane piezoelectric polarization when strained transverse to the basal plane, regardless of the stacking sequence. The out-of-plane piezoelectric coefficient d 33 is found to be strongest in multilayer MoSTe (5.7-13.5 pm/V depending on the stacking sequence), which is larger than that of the commonly used 3D piezoelectric material AlN (d 33 = 5.6 pm/V); d 33 in other multilayer MXY structures are a bit smaller, but still comparable. Our study reveals the potential for utilizing piezoelectric 2D materials and their van der Waals multilayers in device applications.

Prediction and control of pillow defect in single point incremental forming using numerical simulations

International Nuclear Information System (INIS)

Isidore, B. B. Lemopi; Hussain, G.; Khan, Wasim A.; Shamachi, S. Pourhassan

2016-01-01

Pillows formed at the center of sheets in Single point incremental forming (SPIF) are fabrication defects which adversely affect the geometrical accuracy and formability of manufactured parts. This study is focused on using FEA as a tool to predict and control pillowing in SPIF by varying tool size and shape. 3D Finite element analysis (FEA) and experiments are carried out using annealed Aluminum 1050. From FEA, it is found out that the stress/strain state in the immediate vicinity of the forming tool in the transverse direction plays a determinant role on sheet pillowing. Furthermore, pillow height increases as compression in the sheet-plane increases. The nature of in-plane stresses in the transverse direction varies from compressive to tensile as the tool-end geometry is changed from spherical to flat. Additionally, the magnitude of corresponding in-plane stresses decreases as the tool radius increases. According to measurements from the FEA model, flat end tools and large radii both retard pillow formation. However, the influence of changing tool end shape from hemispherical to flat is observed to be more important than the effect of varying tool radius, because the deformation zone remains in tension in the transverse direction while forming with flat end tools. These findings are verified by conducting a set of experiments. A fair agreement between the FEM and empirical results show that FEM can be employed as a tool to predict and control the pillow defect in SPIF.

Prediction and control of pillow defect in single point incremental forming using numerical simulations

Energy Technology Data Exchange (ETDEWEB)

Isidore, B. B. Lemopi [Eastern Mediterranean University, Gazimagusa (Turkmenistan); Hussain, G.; Khan, Wasim A. [GIK Institute of Engineering, Swabi (Pakistan); Shamachi, S. Pourhassan [University of Minho, Guimaraes (Portugal)

2016-05-15

Pillows formed at the center of sheets in Single point incremental forming (SPIF) are fabrication defects which adversely affect the geometrical accuracy and formability of manufactured parts. This study is focused on using FEA as a tool to predict and control pillowing in SPIF by varying tool size and shape. 3D Finite element analysis (FEA) and experiments are carried out using annealed Aluminum 1050. From FEA, it is found out that the stress/strain state in the immediate vicinity of the forming tool in the transverse direction plays a determinant role on sheet pillowing. Furthermore, pillow height increases as compression in the sheet-plane increases. The nature of in-plane stresses in the transverse direction varies from compressive to tensile as the tool-end geometry is changed from spherical to flat. Additionally, the magnitude of corresponding in-plane stresses decreases as the tool radius increases. According to measurements from the FEA model, flat end tools and large radii both retard pillow formation. However, the influence of changing tool end shape from hemispherical to flat is observed to be more important than the effect of varying tool radius, because the deformation zone remains in tension in the transverse direction while forming with flat end tools. These findings are verified by conducting a set of experiments. A fair agreement between the FEM and empirical results show that FEM can be employed as a tool to predict and control the pillow defect in SPIF.

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

Intervertebral anticollision constraints improve out-of-plane translation accuracy of a single-plane fluoroscopy-to-CT registration method for measuring spinal motion

International Nuclear Information System (INIS)

Lin, Cheng-Chung; Tsai, Tsung-Yuan; Hsu, Shih-Jung; Lu, Tung-Wu; Shih, Ting-Fang; Wang, Ting-Ming

2013-01-01

Purpose: The study aimed to propose a new single-plane fluoroscopy-to-CT registration method integrated with intervertebral anticollision constraints for measuring three-dimensional (3D) intervertebral kinematics of the spine; and to evaluate the performance of the method without anticollision and with three variations of the anticollision constraints via an in vitro experiment. Methods: The proposed fluoroscopy-to-CT registration approach, called the weighted edge-matching with anticollision (WEMAC) method, was based on the integration of geometrical anticollision constraints for adjacent vertebrae and the weighted edge-matching score (WEMS) method that matched the digitally reconstructed radiographs of the CT models of the vertebrae and the measured single-plane fluoroscopy images. Three variations of the anticollision constraints, namely, T-DOF, R-DOF, and A-DOF methods, were proposed. An in vitro experiment using four porcine cervical spines in different postures was performed to evaluate the performance of the WEMS and the WEMAC methods. Results: The WEMS method gave high precision and small bias in all components for both vertebral pose and intervertebral pose measurements, except for relatively large errors for the out-of-plane translation component. The WEMAC method successfully reduced the out-of-plane translation errors for intervertebral kinematic measurements while keeping the measurement accuracies for the other five degrees of freedom (DOF) more or less unaltered. The means (standard deviations) of the out-of-plane translational errors were less than −0.5 (0.6) and −0.3 (0.8) mm for the T-DOF method and the R-DOF method, respectively. Conclusions: The proposed single-plane fluoroscopy-to-CT registration method reduced the out-of-plane translation errors for intervertebral kinematic measurements while keeping the measurement accuracies for the other five DOF more or less unaltered. With the submillimeter and subdegree accuracy, the WEMAC method was

NaCl-assisted one-step growth of MoS2-WS2 in-plane heterostructures

Science.gov (United States)

Wang, Zhan; Xie, Yong; Wang, Haolin; Wu, Ruixue; Nan, Tang; Zhan, Yongjie; Sun, Jing; Jiang, Teng; Zhao, Ying; Lei, Yimin; Yang, Mei; Wang, Weidong; Zhu, Qing; Ma, Xiaohua; Hao, Yue

2017-08-01

Transition metal dichalcogenides (TMDs) have attracted considerable interest for exploration of next-generation electronics and optoelectronics in recent years. Fabrication of in-plane lateral heterostructures between TMDs has opened up excellent opportunities for engineering two-dimensional materials. The creation of high quality heterostructures with a facile method is highly desirable but it still remains challenging. In this work, we demonstrate a one-step growth method for the construction of high-quality MoS2-WS2 in-plane heterostructures. The synthesis was carried out using ambient pressure chemical vapor deposition (APCVD) with the assistance of sodium chloride (NaCl). It was found that the addition of NaCl played a key role in lowering the growth temperatures, in which the Na-containing precursors could be formed and condensed on the substrates to reduce the energy of the reaction. As a result, the growth regimes of MoS2 and WS2 are better matched, leading to the formation of in-plane heterostructures in a single step. The heterostructures were proved to be of high quality with a sharp and clear interface. This newly developed strategy with the assistance of NaCl is promising for synthesizing other TMDs and their heterostructures.

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

Functional analysis of the cross-section form and X-ray density of human ulnae

International Nuclear Information System (INIS)

Hilgen, B.

1981-01-01

On 20 ulnae the form of the cross sections and distribution of the X-ray density were investigated in five different cross-section heights. The analysis of the cross-section forms was carried through using plane contraction figures, the X-ray density was established by means of the equidensity line method. (orig.) [de

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-wave Least-squares Reverse Time Migration

KAUST Repository

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.

Island dynamics and anisotropy during vapor phase epitaxy of m-plane GaN

Energy Technology Data Exchange (ETDEWEB)

Perret, Edith [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA; University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Chemin du Musée 3, CH-1700 Fribourg, Switzerland; Xu, Dongwei [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA; Highland, M. J. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA; Stephenson, G. B. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA; Zapol, P. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA; Fuoss, P. H. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA; Munkholm, A. [Munkholm Consulting, Mountain View, California 94043, USA; Thompson, Carol [Department of Physics, Northern Illinois University, DeKalb, Illinois 60115, USA

2017-12-04

Using in situ grazing-incidence x-ray scattering, we have measured the diffuse scattering from islands that form during layer-by-layer growth of GaN by metal-organic vapor phase epitaxy on the (1010) m-plane surface. The diffuse scattering is extended in the (0001) in-plane direction in reciprocal space, indicating a strong anisotropy with islands elongated along [1210] and closely spaced along [0001]. This is confirmed by atomic force microscopy of a quenched sample. Islands were characterized as a function of growth rate F and temperature. The island spacing along [0001] observed during the growth of the first monolayer obeys a power-law dependence on growth rate F-n, with an exponent n = 0:25 + 0.02. The results are in agreement with recent kinetic Monte Carlo simulations, indicating that elongated islands result from the dominant anisotropy in step edge energy and not from surface diffusion anisotropy. The observed power-law exponent can be explained using a simple steady-state model, which gives n = 1/4.

[A cephalometric study on determining the orientation of occlusal plane].

Science.gov (United States)

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.

Influence of Si-doping on heteroepitaxially grown a-plane GaN

Energy Technology Data Exchange (ETDEWEB)

Wieneke, Matthias; Bastek, Barbara; Noltemeyer, Martin; Hempel, Thomas; Rohrbeck, Antje; Witte, Hartmut; Veit, Peter; Blaesing, Juergen; Dadgar, Armin; Christen, Juergen; Krost, Alois [Otto-von-Guericke-Universitaet Magdeburg, FNW/IEP, Universitaetsplatz 2, 39106 Magdeburg (Germany)

2011-07-01

Si-doped a-plane GaN samples with nominal doping levels up to 10{sup 20} cm{sup -3} were grown on r-plane sapphire by metal organic vapor phase epitaxy. Silane flow rates higher than 59 nmol/min lead to three dimensional grown crystallites as revealed by scanning electron microscopy. High resolution X-ray diffraction, photoluminescence and cathodoluminescence suggest considerably reduced defect densities in the large micrometer-sized GaN crystallites. Especially, transmission electron microscopy images verify a very low density of basal plane stacking faults less than 10{sup 4} cm{sup -1} in these crystallites consisting of heteroepitaxially grown a-plane GaN. In our presentation the influence of the Si doping on the basal plane stacking faults will be discussed.

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

The investigation of a two-layer fluid soliton pair using phase plane analysis

International Nuclear Information System (INIS)

Momeni, M.; Moslehi-Fard, M.; Alinejad, H.; Mahmoodi, J.

2004-01-01

Nonlinear long waves theory in a two-layer fluid system has been studied. The dynamical equations according to the normalized heights in first order are obtained using the reductive perturbation method and the equations of shallow water in each fluid and taking boundary conditions appropriate into account. Conserve energy form by definition a independent variable is found. By definition a Lyapunov function, the condition for stability are shown. A new technique was used to prove stability as well as existence of soliton pair using phase plane analysis. (author)

A cephalometric study to determine the plane of occlusion in completely edentulous patients.

Science.gov (United States)

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.

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.

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...

Single-Spin Polarization Effects and the Determination of Timelike Proton Form Factors

Energy Technology Data Exchange (ETDEWEB)

Brodsky, S

2003-10-24

We show that measurements of the proton's polarization in e{sup +}e{sup -} {yields} p{bar p} strongly discriminate between analytic forms of models which fit the proton form factors in the spacelike region. In particular, the single-spin asymmetry normal to the scattering plane measures the relative phase difference between the timelike G{sub E} and G{sub M} form factors. The expected proton polarization in the timelike region is large, of order of several tens of percent.

Acceleration of planes segmentation using normals from previous frame

Science.gov (United States)

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.

Subcostal Transverse Abdominis Plane Block for Acute Pain Management: A Review.

Science.gov (United States)

Soliz, Jose M; Lipski, Ian; Hancher-Hodges, Shannon; Speer, Barbra Bryce; Popat, Keyuri

2017-10-01

The subcostal transverse abdominis plane (SCTAP) block is the deposition of local anesthetic in the transverse abdominis plane inferior and parallel to the costal margin. There is a growing consensus that the SCTAP block provides better analgesia for upper abdominal incisions than the traditional transverse abdominis plane block. In addition, when used as part of a four-quadrant transverse abdominis plane block, the SCTAP block may provide adequate analgesia for major abdominal surgery. The purpose of this review is to discuss the SCTAP block, including its indications, technique, local anesthetic solutions, and outcomes.

Positioning of electrode plane systematically influences EIT imaging.

Science.gov (United States)

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.

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...

Mid-callosal plane determination using preferred directions from diffusion tensor images

Science.gov (United States)

Costa, André L.; Rittner, Letícia; Lotufo, Roberto A.; Appenzeller, Simone

2015-03-01

The corpus callosum is the major brain structure responsible for inter{hemispheric communication between neurons. Many studies seek to relate corpus callosum attributes to patient characteristics, cerebral diseases and psychological disorders. Most of those studies rely on 2D analysis of the corpus callosum in the mid-sagittal plane. However, it is common to find conflicting results among studies, once many ignore methodological issues and define the mid-sagittal plane based on precary or invalid criteria with respect to the corpus callosum. In this work we propose a novel method to determine the mid-callosal plane using the corpus callosum internal preferred diffusion directions obtained from diffusion tensor images. This plane is analogous to the mid-sagittal plane, but intended to serve exclusively as the corpus callosum reference. Our method elucidates the great potential the directional information of the corpus callosum fibers have to indicate its own referential. Results from experiments with five image pairs from distinct subjects, obtained under the same conditions, demonstrate the method effectiveness to find the corpus callosum symmetric axis relative to the axial plane.

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....

Blackfolds, plane waves and minimal surfaces

Science.gov (United States)

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.

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.

Multi-planed unified switching topologies

Science.gov (United States)

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.

Hydrodynamics of planing monohull watercraft

CERN Document Server

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)

NeuroSeek dual-color image processing infrared focal plane array

Science.gov (United States)

McCarley, Paul L.; Massie, Mark A.; Baxter, Christopher R.; Huynh, Buu L.

1998-09-01

Several technologies have been developed in recent years to advance the state of the art of IR sensor systems including dual color affordable focal planes, on-focal plane array biologically inspired image and signal processing techniques and spectral sensing techniques. Pacific Advanced Technology (PAT) and the Air Force Research Lab Munitions Directorate have developed a system which incorporates the best of these capabilities into a single device. The 'NeuroSeek' device integrates these technologies into an IR focal plane array (FPA) which combines multicolor Midwave IR/Longwave IR radiometric response with on-focal plane 'smart' neuromorphic analog image processing. The readout and processing integrated circuit very large scale integration chip which was developed under this effort will be hybridized to a dual color detector array to produce the NeuroSeek FPA, which will have the capability to fuse multiple pixel-based sensor inputs directly on the focal plane. Great advantages are afforded by application of massively parallel processing algorithms to image data in the analog domain; the high speed and low power consumption of this device mimic operations performed in the human retina.

A novel fabrication process for out-of-plane microneedle sheets of biocompatible polymer

Science.gov (United States)

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.

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

Optimal distance of multi-plane sensor in three-dimensional electrical impedance tomography.

Science.gov (United States)

Hao, Zhenhua; Yue, Shihong; Sun, Benyuan; Wang, Huaxiang

2017-12-01

Electrical impedance tomography (EIT) is a visual imaging technique for obtaining the conductivity and permittivity distributions in the domain of interest. As an advanced technique, EIT has the potential to be a valuable tool for continuously bedside monitoring of pulmonary function. The EIT applications in any three-dimensional (3 D) field are very limited to the 3 D effects, i.e. the distribution of electric field spreads far beyond the electrode plane. The 3 D effects can result in measurement errors and image distortion. An important way to overcome the 3 D effect is to use the multiple groups of sensors. The aim of this paper is to find the best space resolution of EIT image over various electrode planes and select an optimal plane spacing in a 3 D EIT sensor, and provide guidance for 3 D EIT electrodes placement in monitoring lung function. In simulation and experiment, several typical conductivity distribution models, such as one rod (central, midway and edge), two rods and three rods, are set at different plane spacings between the two electrode planes. A Tikhonov regularization algorithm is utilized for reconstructing the images; the relative error and the correlation coefficient are utilized for evaluating the image quality. Based on numerical simulation and experimental results, the image performance at different spacing conditions is evaluated. The results demonstrate that there exists an optimal plane spacing between the two electrode planes for 3 D EIT sensor. And then the selection of the optimal plane spacing between the electrode planes is suggested for the electrodes placement of multi-plane EIT sensor.

Goedel, Penrose, anti-Mach: extra supersymmetries of time-dependent plane waves

International Nuclear Information System (INIS)

Blau, Matthias; O'Loughlin, Martin; Meessen, Patrick

2003-01-01

We prove that M-theory plane waves with extra supersymmetries are necessarily homogeneous (but possibly time-dependent), and we show by explicit construction that such time-dependent plane waves can admit extra supersymmetries. To that end we study the Penrose limits of Goedel-like metrics, show that the Penrose limit of the M-theory Goedel metric (with 20 supercharges) is generically a time-dependent homogeneous plane wave of the anti-Mach type, and display the four extra Killings spinors in that case. We conclude with some general remarks on the Killing spinor equations for homogeneous plane waves. (author)

The deployment of routing protocols in distributed control plane of SDN.

Science.gov (United States)

Jingjing, Zhou; Di, Cheng; Weiming, Wang; Rong, Jin; Xiaochun, Wu

2014-01-01

Software defined network (SDN) provides a programmable network through decoupling the data plane, control plane, and application plane from the original closed system, thus revolutionizing the existing network architecture to improve the performance and scalability. In this paper, we learned about the distributed characteristics of Kandoo architecture and, meanwhile, improved and optimized Kandoo's two levels of controllers based on ideological inspiration of RCP (routing control platform). Finally, we analyzed the deployment strategies of BGP and OSPF protocol in a distributed control plane of SDN. The simulation results show that our deployment strategies are superior to the traditional routing strategies.

Goedel, Penrose, anti-Mach: extra supersymmetries of time-dependent plane waves

Energy Technology Data Exchange (ETDEWEB)

Blau, Matthias; O' Loughlin, Martin; Meessen, Patrick [SISSA/ISAS, Via Beirut 2-4, 34014 Trieste (Italy)]. E-mail: meessen@sissa.it

2003-09-01

We prove that M-theory plane waves with extra supersymmetries are necessarily homogeneous (but possibly time-dependent), and we show by explicit construction that such time-dependent plane waves can admit extra supersymmetries. To that end we study the Penrose limits of Goedel-like metrics, show that the Penrose limit of the M-theory Goedel metric (with 20 supercharges) is generically a time-dependent homogeneous plane wave of the anti-Mach type, and display the four extra Killings spinors in that case. We conclude with some general remarks on the Killing spinor equations for homogeneous plane waves. (author)

The Deployment of Routing Protocols in Distributed Control Plane of SDN

Directory of Open Access Journals (Sweden)

Zhou Jingjing

2014-01-01

Full Text Available Software defined network (SDN provides a programmable network through decoupling the data plane, control plane, and application plane from the original closed system, thus revolutionizing the existing network architecture to improve the performance and scalability. In this paper, we learned about the distributed characteristics of Kandoo architecture and, meanwhile, improved and optimized Kandoo’s two levels of controllers based on ideological inspiration of RCP (routing control platform. Finally, we analyzed the deployment strategies of BGP and OSPF protocol in a distributed control plane of SDN. The simulation results show that our deployment strategies are superior to the traditional routing strategies.

Geometric Structure of 3D Spinal Curves: Plane Regions and Connecting Zones

Science.gov (United States)

Berthonnaud, E.; Hilmi, R.; Dimnet, J.

2012-01-01

This paper presents a new study of the geometric structure of 3D spinal curves. The spine is considered as an heterogeneous beam, compound of vertebrae and intervertebral discs. The spine is modeled as a deformable wire along which vertebrae are beads rotating about the wire. 3D spinal curves are compound of plane regions connected together by zones of transition. The 3D spinal curve is uniquely flexed along the plane regions. The angular offsets between adjacent regions are concentrated at level of the middle zones of transition, so illustrating the heterogeneity of the spinal geometric structure. The plane regions along the 3D spinal curve must satisfy two criteria: (i) a criterion of minimum distance between the curve and the regional plane and (ii) a criterion controlling that the curve is continuously plane at the level of the region. The geometric structure of each 3D spinal curve is characterized by the sizes and orientations of regional planes, by the parameters representing flexed regions and by the sizes and functions of zones of transition. Spinal curves of asymptomatic subjects show three plane regions corresponding to spinal curvatures: lumbar, thoracic and cervical curvatures. In some scoliotic spines, four plane regions may be detected. PMID:25031873

Three-dimensional radiative transfer in an isotropically scattering, plane-parallel medium: generalized X- and Y-functions

International Nuclear Information System (INIS)

Mueller, D.W.; Crosbie, A.L.

2005-01-01

The topic of this work is the generalized X- and Y-functions of multidimensional radiative transfer. The physical problem considered is spatially varying, collimated radiation incident on the upper boundary of an isotropically scattering, plane-parallel medium. An integral transform is used to reduce the three-dimensional transport equation to a one-dimensional form, and a modified Ambarzumian's method is used to derive coupled, integro-differential equations for the source functions at the boundaries of the medium. The resulting equations are said to be in double-integral form because the integration is over both angular variables. Numerical results are presented to illustrate the computational characteristics of the formulation

Blocking sets in Desarguesian planes

NARCIS (Netherlands)

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

Wave-equation Migration Velocity Analysis Using Plane-wave Common Image Gathers

KAUST Repository

Guo, Bowen

2017-06-01

Wave-equation migration velocity analysis (WEMVA) based on subsurface-offset, angle domain or time-lag common image gathers (CIGs) requires significant computational and memory resources because it computes higher dimensional migration images in the extended image domain. To mitigate this problem, a WEMVA method using plane-wave CIGs is presented. Plane-wave CIGs reduce the computational cost and memory storage because they are directly calculated from prestack plane-wave migration, and the number of plane waves is often much smaller than the number of shots. In the case of an inaccurate migration velocity, the moveout of plane-wave CIGs is automatically picked by a semblance analysis method, which is then linked to the migration velocity update by a connective function. Numerical tests on two synthetic datasets and a field dataset validate the efficiency and effectiveness of this method.

Transient reaction of an elastic half-plane on a source of a concentrated boundary disturbance

Science.gov (United States)

Okonechnikov, A. S.; Tarlakovski, D. V.; Ul'yashina, A. N.; Fedotenkov, G. V.

2016-11-01

One of the key problems in studying the non-stationary processes of solid mechanics is obtaining of influence functions. These functions serve as solutions for the problems of effect of sudden concentrated loads on a body with linear elastic properties. Knowledge of the influence functions allows us to obtain the solutions for the problems with non-mixed boundary and initial conditions in the form of quadrature formulae with the help of superposition principle, as well as get the integral governing equations for the problems with mixed boundary and initial conditions. This paper offers explicit derivations for all nonstationary surface influence functions of an elastic half-plane in a plane strain condition. It is achieved with the help of combined inverse transform of a Fourier-Laplace integral transformation. The external disturbance is both dynamic and kinematic. The derived functions in xτ-domain are studied to find and describe singularities and are supplemented with graphs.

Formation of whispering gallery modes by scattering of an electromagnetic plane wave by two cylinders

Energy Technology Data Exchange (ETDEWEB)

Abramov, Arnold, E-mail: qulaser@gmail.com [Kuang-Chi Institute of Advanced Technology, Shenzhen, 518057 (China); Kostikov, Alexander [Donbass State Engineering Academy, 84303, Kramatorsk, Donetsk (Ukraine)

2017-03-26

We report the effect of scattering of electromagnetic plane waves by two cylinders on whispering gallery mode (WGM) formation in a cylinder. WGM can occur because of the presence of additional cylinder scatterers at specific location, while WGMs can only form in a single cylinder for specific cylinder radius and/or wavelength values, the matching accuracy required would be much greater than that required in our model for the additional cylinders locations. Analysis of the general solution to the problem showed that the effect can be explained by the interference of waves scattered by additional cylinders and incident on the main cylinder. - Highlights: • We consider scattering of electromagnetic plane waves by two cylinders. • WGMs occur because of the presence of additional cylinder at specific location. • The accuracy for the locations is much less than required for specific values of single cylinder. • The interference of waves scattered by additional cylinders and incident on the main is responsible for the effect.

Extrapolation of π-meson form factor, zeros in the analyticity domain

International Nuclear Information System (INIS)

Morozov, P.T.

1978-01-01

The problem of a stable extrapolation from the cut to an arbitrary interior of the analyticity domain for the pion form factor is formulated and solved. As it is shown a stable solution can be derived if module representations with the Karleman weight function are used as the analyticity conditions. The case when the form factor has zeros is discussed. If there are zeros in the complex plane they must be taken into account when determining the extrapolation function

Elastography for Thyroid Nodules: The Comparison of Diagnostic Performance on Transverse and Longitudinal Planes

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

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)

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

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

Minor Forms in a Badlands Landscape Framework

Energy Technology Data Exchange (ETDEWEB)

Diaz-Hernandez, J. L.; Yepes, J.; Romero-Diaz, A.

2009-07-01

We describe and classify some medium-scale erosional morphologies in badlands areas. They have been categorized in three different types: A) Surficial forms on horizontal surfaces (soil surface crusts, cracks, popcorn) and walls (slips, pseudo-stalactites). B) Punctual fingerprints: rain impact and micro-collapses (dimples). C) Ruiniform morphologies (caves, shelters, residual pinnacles). The A type shapes are caused by damping-desiccation phenomena on clayey soils; morphologies on walls are due to laminar runoff on weak lithologies (clay, loam), also dubbed pseudo-spleleothemes. Their scale is centimetric-decimetric. B-Type forms may be an external passive process (impact) or an internal dynamic process (dimples) occurring in granular sediments inside shelters, in conditions of apparent calm, measuring up to a few centimetres. The caves and shelters of type C generally involve an excavation following stratification or jointing planes, while the residual pinnacles are vertical forms linked to advanced piping and fluting. Both forms are decametric in scale. (Author) 7 refs.

Minor Forms in a Badlands Landscape Framework

International Nuclear Information System (INIS)

Diaz-Hernandez, J. L.; Yepes, J.; Romero-Diaz, A.

2009-01-01

We describe and classify some medium-scale erosional morphologies in badlands areas. They have been categorized in three different types: A) Surficial forms on horizontal surfaces (soil surface crusts, cracks, popcorn) and walls (slips, pseudo-stalactites). B) Punctual fingerprints: rain impact and micro-collapses (dimples). C) Ruiniform morphologies (caves, shelters, residual pinnacles). The A type shapes are caused by damping-desiccation phenomena on clayey soils; morphologies on walls are due to laminar runoff on weak lithologies (clay, loam), also dubbed pseudo-spleleothemes. Their scale is centimetric-decimetric. B-Type forms may be an external passive process (impact) or an internal dynamic process (dimples) occurring in granular sediments inside shelters, in conditions of apparent calm, measuring up to a few centimetres. The caves and shelters of type C generally involve an excavation following stratification or jointing planes, while the residual pinnacles are vertical forms linked to advanced piping and fluting. Both forms are decametric in scale. (Author) 7 refs.

Conquest of the Plane

OpenAIRE

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 ...

Bi-layer graphene structure with non-equivalent planes: Magnetic properties study

Science.gov (United States)

Mhirech, A.; Aouini, S.; Alaoui-Ismaili, A.; Bahmad, L.

2018-05-01

In this paper, we study the magnetic properties of a ferromagnetic bi-layer graphene structure with non-equivalent planes. The geometry of the studied system is formed by two layers (A) and (B) consisting of the spins σ = 1 / 2 and S = 1 . For this purpose, the influence of the coupling exchange interactions, the external magnetic and the crystal fields are investigated and presented as well as the ground state phase diagrams. The Monte Carlo simulations have been used to examine the behavior of the partial and the total magnetizations as a function of the system parameters. These effects on the compensation and critical temperatures behavior are also presented in different phase diagrams, for the studied system.

16 CFR Figure 1 to Part 1203 - Anatomical Planes

Science.gov (United States)

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 ...

Plane partition vesicles

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

Recovery from deep-plane rhytidectomy following unilateral wound treatment with autologous platelet gel: a pilot study.

Science.gov (United States)

Powell, D M; Chang, E; Farrior, E H

2001-01-01

To determine the effects of treatment with autologous platelet-rich plasma mixed with thrombin and calcium chloride to form an autologous platelet gel (APG) on postoperative recovery from deep-plane rhytidectomy. A prospective, randomized, controlled pilot study. An accredited ambulatory facial plastic surgery center. Healthy volunteer women (N = 8) undergoing rhytidectomy. Unilateral autologous platelet-rich plasma wound treatment during standard deep-plane rhytidectomy. Staged postoperative facial photographs were graded in a blinded fashion by 3 facial plastic surgeon reviewers for postoperative ecchymosis and edema. Each facial side treated with APG that demonstrated less edema or ecchymosis than the non-APG-treated side was designated a positive response; otherwise, the response was equal (no difference) or negative (untreated side had less edema or ecchymosis). Twenty-one positive and 21 equal responses were observed compared with 8 negative ones. Of 20 unanimous observations, 15 were positive, only 3 equal, and 1 negative. Treatment with APG may prevent or improve edema or ecchymosis after deep-plane rhytidectomy. This trend is more apparent for ecchymosis than for edema, and is chiefly demonstrable in the early phases of recovery. These observations are consistent with previous reports of cell tissue culture and wound response to concentrated platelet product.

In-plane user positioning indoors

NARCIS (Netherlands)

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

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.

Nonlinear differential equations for the wavefront surface at arbitrary Hartmann-plane distances.

Science.gov (United States)

Téllez-Quiñones, Alejandro; Malacara-Doblado, Daniel; Flores-Hernández, Ricardo; Gutiérrez-Hernández, David A; León-Rodríguez, Miguel

2016-03-20

In the Hartmann test, a wave aberration function W is estimated from the information of the spot diagram drawn in an observation plane. The distance from a reference plane to the observation plane, the Hartmann-plane distance, is typically chosen as z=f, where f is the radius of a reference sphere. The function W and the transversal aberrations {X,Y} calculated at the plane z=f are related by two well-known linear differential equations. Here, we propose two nonlinear differential equations to denote a more general relation between W and the transversal aberrations {U,V} calculated at any arbitrary Hartmann-plane distance z=r. We also show how to directly estimate the wavefront surface w from the information of {U,V}. The use of arbitrary r values could improve the reliability of the measurements of W, or w, when finding difficulties in adequate ray identification at z=f.

Nonpolar a-plane light-emitting diode with an in-situ SiNx interlayer on r-plane sapphire grown by metal-organic chemical vapour deposition

International Nuclear Information System (INIS)

Fang Hao; Long Hao; Sang Li-Wen; Qi Sheng-Li; Xiong Chang; Yu Tong-Jun; Yang Zhi-Jian; Zhang Guo-Yi

2011-01-01

We report on the growth and fabrication of nonpolar a-plane light emitting diodes with an in-situ SiN x interlayer grown between the undoped a-plane GaN buffer and Si-doped GaN layer. X-ray diffraction shows that the crystalline quality of the GaN buffer layer is greatly improved with the introduction of the SiN x interlayer. The electrical properties are also improved. For example, electron mobility and sheet resistance are reduced from high resistance to 31.6 cm 2 /(V·s) and 460 Ω/□ respectively. Owing to the significant effect of the SiN x interlayer, a-plane LEDs are realized. Electroluminescence of a nonpolar a-plane light-emitting diode with a wavelength of 488nm is demonstrated. The emission peak remains constant when the injection current increases to over 20 mA. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Quantum fields interacting with colliding plane waves: the stress-energy tensor and backreaction

International Nuclear Information System (INIS)

Dorca, M.; Verdaguer, E.

1997-01-01

Following a previous work on the quantization of a massless scalar field in a space-time representing the head on collision of two plane waves which focus into a Killing-Cauchy horizon, we compute the renormalized expectation value of the stress-energy tensor of the quantum field near that horizon in the physical state which corresponds to the Minkowski vacuum before the collision of the waves. It is found that for minimally coupled and conformally coupled scalar fields the respective stress-energy tensors are unbounded in the horizon. The specific form of the divergences suggests that when the semiclassical Einstein equations describing the backreaction of the quantum fields on the space-time geometry are taken into account, the horizon will acquire a curvature singularity. Thus the Killing-Cauchy horizon which is known to be unstable under ''generic'' classical perturbations is also unstable by vacuum polarization. The calculation is done following the point-splitting regularization technique. The dynamical colliding wave space-time has four quite distinct space-time regions, namely, one flat region, two single plane wave regions, and one interaction region. Exact mode solutions of the quantum field equation cannot be found exactly, but the blueshift suffered by the initial modes in the plane wave and interaction regions makes the use of the WKB expansion a suitable method of solution. To ensure the correct regularization of the stress-energy tensor, the initial flat modes propagated into the interaction region must be given to a rather high adiabatic order of approximation. (orig.)

Ferrofluid spiral formations and continuous-to-discrete phase transitions under simultaneously applied DC axial and AC in-plane rotating magnetic fields

International Nuclear Information System (INIS)

Rhodes, Scott; Perez, Juan; Elborai, Shihab; Lee, Se-Hee; Zahn, Markus

2005-01-01

New flows and instabilities are presented for a ferrofluid drop contained in glass Hele-Shaw cells with simultaneously applied in-plane clockwise rotating and DC axial uniform magnetic fields. When a ferrofluid drop is stressed by a uniform DC axial magnetic field, up to ∼250 G in 0.9-1.4 mm gap Hele-Shaw cells, the drop forms a labyrinth pattern. With subsequent application of an in-plane uniform rotating magnetic field, up to ∼100 G rms at frequency 20-40 Hz, smooth spirals form from viscous shear due to ferrofluid flow. If the rotating magnetic field is applied first, the drop is held together without a labyrinth. Gradual increase of the DC axial magnetic field, to a critical magnetic field value, results in an abrupt phase transformation from a large drop to many small discrete droplets. A preliminary minimum magnetization and surface energy analysis is presented to model the phase transformation

A Panoramic View of Star Formation in Milky Way: Recent Results from Galactic Plane FIR/Sub-mm Surveys

Science.gov (United States)

Elia, Davide

2017-11-01

The star formation process involves a continuous gas flow from galactic (kpc) down to stellar (AU) scales. While targeted observations of single star forming sources are needed to understand the steps of this process with increasing detail, large unbiased Galactic plane surveys permit to reconstruct the map of star forming sites across the Milky Way, considered as an unique star formation engine. On the one hand, such surveys provide the community with a huge number of candidate targets for future follow-up observations with state-of-the-art telescope facilities, on the other hand they can provide reliable estimates of global parameters, such as Galactic star formation efficiency and rate, through which it is possible to establish comparisons with other galaxies. In this talk I will review the main results of recent FIR/sub-mm continuum emission Galactic surveys, with special attention to the Hi-GAL Herschel project, having the advantage (but also the complication) of being a multi-wavelength survey covering the spectral range in which the cold interstellar dust is expected to emit. The subsequent VIALACTEA project represents an articulate effort to combine Hi-GAL with other continuum and line surveys to refine the census of star forming clumps in the Galactic plane, and to use it to describe the Milky Way as a whole. Interpretation limitations imposed by the loss of detail with increasing distance are also discussed.

Processing of plane strain compression test results for investigation of AISI-304 stainless steel constitutive behavior

International Nuclear Information System (INIS)

Aksenov, Sergey A.; Puzino, Yuriy A.; Bober, Stanislav A.; Kliber, Jiri

2015-01-01

The paper is oriented toward the determination of constitutive equation constants by the inverse analysis of plane strain compression test results. The interpretation of such results is complicated by the inhomogeneity of strain rate distribution in the specimen caused by rigid ends, the lateral spreading of a specimen friction and the variation of temperature during the test. The results of plane strain compression tests of AISI-304 stainless steel are presented and significant deviations of temperature are observed at higher strain rates. Finite element simulation was performed to estimate the inhomogeneity of strain rate within the specimen and evaluate the effect of friction on the test results. Constitutive equations of the material were obtained by inverse analysis minimizing the deviations between the measured load values and the ones predicted by numerical simulation. Keywords: PSCT, AISI-304, Gleeble, constitutive equations, hot forming, FEM, inverse analysis.

Free field theories of spin-mass trajectories and quantum electrodynamics in the null plane

Energy Technology Data Exchange (ETDEWEB)

Bart, G.R.; Fenster, S.

1976-06-01

The ten generators of the Poincare algebra for quantum electrodynamics and other gauge theories are given in the null plane. The explicit correspondence of their field-theoretic form to the Bacry-Chang group-theoretic form in the free case is pointed out. It is then noticed that the forms are independent of the spin and allow inclusion of charge quantum numbers at will, which indicates that they represent an advantageous free-particle starting point for a hadron theory with positive spin-mass trajectories (SMT) and with interaction. The internal oscillator content is extracted for both gauge theories and dual resonance models. Interactions are cubic and quartic in the fields. In the dual model they encompass the SMT, whereas no straightforward extension to SMT is possible for the manifestly covariant theories. The requirements of a field-theoretic SMT interaction are spelled out in an algebraic form which guarantees Poincare invariance; however no such interaction is yet known. The approach indicates how a realistic spectrum might be achieved without composite hadrons and incorporating full Poincare invariance.

Free field theories of spin-mass trajectories and quantum electrodynamics in the null plane

International Nuclear Information System (INIS)

Bart, G.R.; Fenster, S.

1976-06-01

The ten generators of the Poincare algebra for quantum electrodynamics and other gauge theories are given in the null plane. The explicit correspondence of their field-theoretic form to the Bacry-Chang group-theoretic form in the free case is pointed out. It is then noticed that the forms are independent of the spin and allow inclusion of charge quantum numbers at will, which indicates that they represent an advantageous free-particle starting point for a hadron theory with positive spin-mass trajectories (SMT) and with interaction. The internal oscillator content is extracted for both gauge theories and dual resonance models. Interactions are cubic and quartic in the fields. In the dual model they encompass the SMT, whereas no straightforward extension to SMT is possible for the manifestly covariant theories. The requirements of a field-theoretic SMT interaction are spelled out in an algebraic form which guarantees Poincare invariance; however no such interaction is yet known. The approach indicates how a realistic spectrum might be achieved without composite hadrons and incorporating full Poincare invariance

Dry patch formed boiling and burnout in potassium pool boiling

International Nuclear Information System (INIS)

Michiyoshi, I.; Takenaka, N.; Takahashi, O.

1986-01-01

Experimental results are presented on dry patch formed boiling and burnout in saturated potassium pool boiling on a horizontal plane heater for system pressures from 30 to 760 torr and liquid levels from 5 to 50 mm. The dry patch formation occurs in the intermittent boiling which is often encountered when liquid alkali metals are used under relatively low pressure conditions. Burnout is caused from both continuous nucleate and dry patch formed boiling. The burnout heat flux together with nucleate boiling heat transfer coefficients are empirically correlated with system pressures. A model is also proposed to predict the minimum heat flux to form the dry patch. (author)

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

A 1.3 giga pixels focal plane for GAIA

Science.gov (United States)

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.

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...

3D-Structured Stretchable Strain Sensors for Out-of-Plane Force Detection.

Science.gov (United States)

Liu, Zhiyuan; Qi, Dianpeng; Leow, Wan Ru; Yu, Jiancan; Xiloyannnis, Michele; Cappello, Leonardo; Liu, Yaqing; Zhu, Bowen; Jiang, Ying; Chen, Geng; Masia, Lorenzo; Liedberg, Bo; Chen, Xiaodong

2018-05-17

Stretchable strain sensors, as the soft mechanical interface, provide the key mechanical information of the systems for healthcare monitoring, rehabilitation assistance, soft exoskeletal devices, and soft robotics. Stretchable strain sensors based on 2D flat film have been widely developed to monitor the in-plane force applied within the plane where the sensor is placed. However, to comprehensively obtain the mechanical feedback, the capability to detect the out-of-plane force, caused by the interaction outside of the plane where the senor is located, is needed. Herein, a 3D-structured stretchable strain sensor is reported to monitor the out-of-plane force by employing 3D printing in conjunction with out-of-plane capillary force-assisted self-pinning of carbon nanotubes. The 3D-structured sensor possesses large stretchability, multistrain detection, and strain-direction recognition by one single sensor. It is demonstrated that out-of-plane forces induced by the air/fluid flow are reliably monitored and intricate flow details are clearly recorded. The development opens up for the exploration of next-generation 3D stretchable sensors for electronic skin and soft robotics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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)

In-Plane Vibrations of Circular Curved Beams with a Transverse Open Crack

OpenAIRE

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. ...

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.

Spatial judgments in the horizontal and vertical planes from different vantage points.

Science.gov (United States)

Prytz, Erik; Scerbo, Mark W

2012-01-01

Todorović (2008 Perception 37 106-125) reported that there are systematic errors in the perception of 3-D space when viewing 2-D linear perspective drawings depending on the observer's vantage point. Because these findings were restricted to the horizontal plane, the current study was designed to determine the nature of these errors in the vertical plane. Participants viewed an image containing multiple colonnades aligned on parallel converging lines receding to a vanishing point. They were asked to judge where, in the physical room, the next column should be placed. The results support Todorović in that systematic deviations in the spatial judgments depended on vantage point for both the horizontal and vertical planes. However, there are also marked differences between the two planes. While judgments in both planes failed to compensate adequately for the vantage-point shift, the vertical plane induced greater distortions of the stimulus image itself within each vantage point.

Decagonal quasicrystal plate with elliptic holes subjected to out-of-plane bending moments

Energy Technology Data Exchange (ETDEWEB)

Li, Lian He, E-mail: nmglilianhe@163.com [College of Mathematics Science, Inner Mongolia Normal University, Hohhot 010022 (China); College of Physical Science and Technology, Inner Mongolia University, Hohhot 010021 (China); Inner Mongolia Key Lab of Nanoscience and Nanotechnology, Hohhot 010021 (China); Liu, Guan Ting [College of Mathematics Science, Inner Mongolia Normal University, Hohhot 010022 (China)

2014-02-01

In the present paper, we consider only the ideal elastic behavior, neglecting the dissipation associated with the atomic rearrangements. Under these conditions, the decagonal quasicrystal plate bending problems have been discussed. The Stroh-like formalism for the bending theory of decagonal quasicrystal plate is developed. The analytical solutions for problems of decagonal quasicrystal plate with elliptic hole subjected to out-of-plane bending moments are obtained directly by using the forms. The resultant bending moments around the hole boundaries are also given explicitly. When the phonon–phason coupling is absent, the results reduce to the corresponding solutions for the isotropic elastic plates.

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.

Out-of-plane coercive field of Ni{sub 80}Fe{sub 20} antidot arrays

Energy Technology Data Exchange (ETDEWEB)

Chunhong, Gao [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China); Ke, Chen [Chongqing Electric Power College, Chongqing (China); Ling, Lue; Jianwei, Zhao [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China); Chen Peng, E-mail: pchen@swu.edu.c [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China)

2010-11-15

The out-of-plane magnetic anisotropy and out-of-plane magnetization reversal process of nanoscale Ni{sub 80}Fe{sub 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{sub 80}Fe{sub 20} antidot arrays shows that the maximum remanence is in-plane and the squareness of the out-of-plane hysteresis loop follow a |cos {theta}| dependence. The angular dependence of out-of-plane coercivity of Ni{sub 80}Fe{sub 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.

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)

Studies of low current back-discharge in point-plane geometry with dielectric layer

International Nuclear Information System (INIS)

Jaworek, A.; Rajch, E.; Czech, T.; Lackowski, M

2005-01-01

The paper presents results of spectroscopic investigations of back-discharge generated in the point-plane electrode geometry in air at atmospheric pressure, with the plane covered with fly ash layer. Four forms of the discharges were studied: onset streamers, glow, breakdown streamers and low-current back-arc discharge. Both polarities of the active discharge electrode, positive and negative, were tested. The back discharge is a type of DC electrical discharge, which take place when the passive plane electrode is covered with a dielectric layer. The layer can be made of solid material or a packed bed of dust or powder of low conductivity. The charge produced due to ionisation processes in the vicinity of the active point electrode is accumulated on the dielectric surface, and generates high electric field through this layer. When critical electric field through the layer is attained an electrical breakdown of the layer take place. The point of breakdown becomes a new source of ions of polarity opposite to those generated by the active electrode. The dielectric layer on the passive electrode causes that gaseous discharges such as breakdown streamers or arc start at lower voltages than they could in the case of normal corona discharge. The visual forms of the discharge were recorded and correlated with the current-voltage characteristics and optical emission spectra. Emission spectra of the discharge were measured in the light wavelength range of 200 to 600 nm to get information about excitation and ionisation processes. The light spectra were analysed by monochromator SPM-2 Karl-Zeiss-Jena with diffraction grating of 1302 grooves/mm and photomultiplier R375 (Hamamatsu) and signal preamplifier unit C7319 (Hamamatsu). The spectral analysis showed that the nitrogen molecular bands were dominant, but the emission of negative ions from the dielectric layer material were also detected. The most noticeable light emission in the range from 280 to 490 nm due to second

Investigation of the in-plane and out-of-plane electrical properties of metallic nanoparticles in dielectric matrix thin films elaborated by atomic layer deposition

Science.gov (United States)

Thomas, D.; Puyoo, E.; Le Berre, M.; Militaru, L.; Koneti, S.; Malchère, A.; Epicier, T.; Roiban, L.; Albertini, D.; Sabac, A.; Calmon, F.

2017-11-01

Pt nanoparticles in a Al2O3 dielectric matrix thin films are elaborated by means of atomic layer deposition. These nanostructured thin films are integrated in vertical and planar test structures in order to assess both their in-plane and out-of-plane electrical properties. A shadow edge evaporation process is used to develop planar devices with electrode separation distances in the range of 30 nm. Both vertical and planar test structures show a Poole-Frenkel conduction mechanism. Low trap energy levels (<0.1 eV) are identified for the two test structures which indicates that the Pt islands themselves are not acting as traps in the PF mechanism. Furthermore, a more than three order of magnitude current density difference is observed between the two geometries. This electrical anisotropy is attributed to a large electron mobility difference in the in-plane and out-of-plane directions which can be related to different trap distributions in both directions.

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

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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.

Control of in-plane texture of body centered cubic metal thin films

International Nuclear Information System (INIS)

Harper, J.M.; Rodbell, K.P.; Colgan, E.G.; Hammond, R.H.

1997-01-01

We show that dramatically different in-plane textures can be produced in body centered cubic (bcc) metal thin films deposited on amorphous substrates under different deposition conditions. The crystallographic orientation distribution of polycrystalline bcc metal thin films on amorphous substrates often has a strong left-angle 110 right-angle fiber texture, indicating that {110} planes are parallel to the substrate plane. When deposition takes place under bombardment by energetic ions or atoms at an off-normal angle of incidence, the left-angle 110 right-angle fiber texture develops an in-plane texture, indicating nonrandom azimuthal orientations of the crystallites. Three orientations in Nb films have been observed under different deposition geometries, in which the energetic particle flux coincides with channeling directions in the bcc crystal structure. In-plane orientations in Mo films have also been obtained in magnetron sputtering systems with various configurations. These are described, and an example is given in which the in-plane orientation of Mo films deposited in two different in-line magnetron sputtering systems differs by a 90 degree rotation. In these two cases, there is a strong left-angle 110 right-angle fiber texture, but the in-plane left-angle 100 right-angle direction is oriented parallel to the scan direction in one system, and perpendicular to the scan direction in the other system. The conditions which produce such different in-plane textures in two apparently similar sputtering systems are discussed. copyright 1997 American Institute of Physics

Three-Dimensional Interaction of a Large Number of Dense DEP Particles on a Plane Perpendicular to an AC Electrical Field

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Chuanchuan Xie

2017-01-01

Full Text Available The interaction of dielectrophoresis (DEP particles in an electric field has been observed in many experiments, known as the “particle chains phenomenon”. However, the study in 3D models (spherical particles is rarely reported due to its complexity and significant computational cost. In this paper, we employed the iterative dipole moment (IDM method to study the 3D interaction of a large number of dense DEP particles randomly distributed on a plane perpendicular to a uniform alternating current (AC electric field in a bounded or unbounded space. The numerical results indicated that the particles cannot move out of the initial plane. The similar particles (either all positive or all negative DEP particles always repelled each other, and did not form a chain. The dissimilar particles (a mixture of positive and negative DEP particles always attracted each other, and formed particle chains consisting of alternately arranged positive and negative DEP particles. The particle chain patterns can be randomly multitudinous depending on the initial particle distribution, the electric properties of particles/fluid, the particle sizes and the number of particles. It is also found that the particle chain patterns can be effectively manipulated via tuning the frequency of the AC field and an almost uniform distribution of particles in a bounded plane chip can be achieved when all of the particles are similar, which may have potential applications in the particle manipulation of microfluidics.

Epitaxial growth of Sb-doped nonpolar a-plane ZnO thin films on r-plane sapphire substrates by RF magnetron sputtering

Energy Technology Data Exchange (ETDEWEB)

Chen, Hou-Guang, E-mail: houguang@isu.edu.tw [Department of Materials Science and Engineering, I-Shou University, Kaohsiung 840, Taiwan (China); Hung, Sung-Po [Department of Materials Science and Engineering, I-Shou University, Kaohsiung 840, Taiwan (China)

2014-02-15

Highlights: ► Sb-doped nonpolar a-plane ZnO layers were epitaxially grown on sapphire substrates. ► Crystallinity and electrical properties were studied upon growth condition and doping concentration. ► The out-of-plane lattice spacing of ZnO films reduces monotonically with increasing Sb doping level. ► The p-type conductivity of ZnO:Sb film is closely correlated with annealing condition and Sb doping level. -- Abstract: In this study, the epitaxial growth of Sb-doped nonpolar a-plane (112{sup ¯}0) ZnO thin films on r-plane (11{sup ¯}02) sapphire substrates was performed by radio-frequency magnetron sputtering. The influence of the sputter deposition conditions and Sb doping concentration on the microstructural and electrical properties of Sb-doped ZnO epitaxial films was investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and the Hall-effect measurement. The measurement of the XRD phi-scan indicated that the epitaxial relationship between the ZnO:Sb layer and sapphire substrate was (112{sup ¯}0){sub ZnO}//(11{sup ¯}02){sub Al{sub 2O{sub 3}}} and [11{sup ¯}00]{sub ZnO}//[112{sup ¯}0]{sub Al{sub 2O{sub 3}}}. The out-of-plane a-axis lattice parameter of ZnO films was reduced monotonically with the increasing Sb doping level. The cross-sectional transmission electron microscopy (XTEM) observation confirmed the absence of any significant antimony oxide phase segregation across the thickness of the Sb-doped ZnO epitaxial film. However, the epitaxial quality of the films deteriorated as the level of Sb dopant increased. The electrical properties of ZnO:Sb film are closely correlated with post-annealing conditions and Sb doping concentrations.

Wood working: planing and moulding in the last frontier

Science.gov (United States)

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...

Improvement of image quality of holographic projection on tilted plane using iterative algorithm

Science.gov (United States)

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.

Endoscopic facelift of the frontal and temporal areas in multiple planes.

Science.gov (United States)

Hu, Xiaogen; Ma, Haihuan; Xue, Zhiqiang; Qi, Huijie; Chen, Bo

2017-02-01

The detachment planes used in endoscopic facelifts play an important role in determining the results of facial rejuvenation. In this study, we introduced the use of multiple detachment planes for endoscopic facelifts of the frontal and temporal areas, and examined its outcome. This study included 47 patients (38 female, 9 male) who requested frontal and temporal facelifts from January 2009 to January 2014. The technique of dissection in multiple planes was used for all 47 patients. In this technique, the frontal dissection was first carried out in the subgaleal plane, before being changed to the subperiosteal plane about 2 cm above the eyebrow line. Temporal dissection was carried out in both the subcutaneous and subgaleal planes. After detachment, frontal and temporal fixations were achieved using nonabsorbable sutures, and the incisions were closed. During follow-up (ranging from 6-24 months after surgery), the patients were shown their pre- and postoperative images, and asked to rate their satisfaction with the procedure. Complications encountered were documented. All 47 patients had complete recovery without any serious complications. The patient satisfaction rate was 93.6%. Minor complications included dimpling at the suture site, asymmetry, overcorrection, transitory paralysis, late oedema, haematoma, infection, scarring and hair loss. These complications resolved spontaneously and were negligible after complete recovery. Dissection in multiple planes is valuable in frontal and temporal endoscopic facelifts. It may be worthwhile to introduce the use of this technique in frontal and temporal facelifts, as it may lead to improved outcomes. Copyright: © Singapore Medical Association

Retrograde lag screw placement in anterior acetabular column with regard to the anterior pelvic plane and midsagittal plane -- virtual mapping of 260 three-dimensional hemipelvises for quantitative anatomic analysis.

Science.gov (United States)

Ochs, Bjoern Gunnar; Stuby, Fabian Maria; Ateschrang, Atesch; Stoeckle, Ulrich; Gonser, Christoph Emanuel

2014-10-01

Percutaneous screw placement can be used for minimally invasive treatment of none or minimally displaced fractures of the anterior column. The complex pelvic geometry can pose a major challenge even for experienced surgeons. The present study examined the preformed bone stock of the anterior column in 260 hemipelvises (130 male and 130 female). Screws were virtually implanted using iPlan(®) CMF (BrainLAB AG, Feldkirchen, Germany); the maximal implant length and the maximal implant diameter were assessed. The study showed, that 6.5mm can generally be used in men; in women however individual planning is essential in regard to the maximal implant diameter since we found that in 15.4% of women, screws with a diameter less than 6.5mm were necessary. The virtual analysis of the preformed bone stock corridor of the anterior column showed two constrictions of crucial clinical importance. These can be found after 18% and 55% (men) respectively 16% and 55% (women) measured from the entry point along the axis of the implant. The entry point of the retrograde anterior column screw in our collective was located lateral of tuberculum pubicum at the level of the superior-medial margin of foramen obturatum. In female patients, the entry point was located significantly more lateral of symphysis and closer to the cranial margin of ramus superior ossis pubis. The mean angle between the screw trajectory and the anterior pelvic plane in sagittal section was 31.6 ± 5.5°, the mean angle between the screw trajectory and the midsagittal plane in axial section was 55.9 ± 4.6° and the mean angle between the screw trajectory and the midsagittal plane in coronal section was 42.1 ± 3.9° with no significant deviation between both sexes. The individual angles formed by the screw trajectory and the anterior pelvic and midsagittal plane are independent from anthropometric parameters sex, age, body length and weight. Therefore, they can be used for orientation in lag screw placement keeping

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...

Three-dimensional microstructural effects on plane strain ductile crack growth

DEFF Research Database (Denmark)

Tvergaard, Viggo; Needleman, Alan

2006-01-01

Ductile crack growth under mode 1, plane strain, small scale yielding conditions is analyzed. Overall plane strain loading is prescribed, but a full 3D analysis is carried out to model three dimensional microstructural effects. An elastic-viscoplastic constitutive relation for a porous plastic...

Out-of-plane reflections - are they evidence for deep subducted lithosphere?

Science.gov (United States)

Schumacher, Lina; Thomas, Christine

2015-04-01

Subduction zones form dominant tectonic features on the Earth and have complex three-dimensional structures. Tomographic inversions for P- and S-wave seismic velocities in the Earth's mantle give impressive images of slabs descending into the deep Earth. However, direct observations of deep slabs are scarce but necessary to make statements concerning physical parameters, structural differences within the slab and its behavior with depth. The main objective of this study is to investigate the geometry, physical parameters and structural differences of subducted lithosphere by investigating seismic P-wave arrivals that reflect off the base of the slab using seismic array techniques. The great circle paths of the source-receiver combinations used do not intersect the slab and serve as reference. We focus on the North pacific region by using earthquakes from Japan, the Philippines and the Hindukush recorded at North American networks (e.g. USArray, Alaska and Canada). The data cover a period from 2000-2012 with a minimum magnitude of 5.6 Mw and depths below 100 km. We are looking for reflections from the slab region that would arrive at the stations with deviating backazimuths. Information on slowness, backazimuth and travel time of the observed out-of-plane arrivals is used to backtrace the wave to its scattering location and to map seismic heterogeneities associated with subduction zones. The reflection points give an idea for the 3D structures within the mantle. Assuming only single scattering in the backtracing algorithm, most out-of-plane signals have to travel as P*P and only a few as S*P phases, due to their timing. Taking into account the radiation pattern of each event in direction of the great circle path and towards the calculated reflection point, it is possible to compare the polarities of the out-of-plane signals with P and/or PP. Furthermore, we analyze the out-of-plane waveforms in the beam trace of the observed slowness and backazimuth by cross

Carbon nanotube plane fastener

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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.

Scattering on plane waves and the double copy

Science.gov (United States)

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.

On deformation of complex continuum immersed in a plane space

Science.gov (United States)

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.

A collapse pressure prediction model for horizontal shale gas wells with multiple weak planes

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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.

SAFE-PLANE, Stress Analysis of Planar Structure by Finite Elements Method

International Nuclear Information System (INIS)

Cornell, D.C.; Reich, Morris

1967-01-01

1 - Description of problem or function: SAFE-PLANE is applied to two- dimensional structures of arbitrary geometry under in-plane loads. Either plane stress or plane strain conditions may be imposed. Mechanical and thermal loads are permitted. 2 - Method of solution: The finite-element method is used to construct a mathematical model by assembling discrete elements. The total potential energy of the structure is determined and subsequently minimized by iteration on components of the displacement field until static equilibrium of the structure is attained. Strains and stresses are computed from the resulting displacements. 3 - Restrictions on the complexity of the problem: Multi-material structures with varying rigidities converge very slowly. Not valid for incompressible materials. Maximum number of nodal points = 675. Maximum number of elements = 1350

ANALYSIS OF A RIGID WALL IN AN ELASTIC WEIGHTY HALF-PLANE

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K. V. Dmitrieva

2016-01-01

Full Text Available The analysis of stress-strain state of a rigid wall in an elastic weighty half-plane with a broken outline is carried out. To this end, the auxiliary problem of displacements definition in an elastic weighty quarter-plane was solved. Ritz method derived a formula to determine the displacements of elastic flat wedge boundaries in view of its own weight. On the basis of the received expressions the algorithm of displacements definition of a crack in an elastic weighty half-plane with a broken outline is developed. Analytical calculation of a rigid vertical wall located in an elastic weighty half-plane under the influence of a horizontal load, carried out by two methods: by Zhemochkin's method and finite difference method. In the problem statement an elastic half-plane is considered a model of the soil medium, therefore, only compressive normal stresses can arise on the connection of the wall with the elastic base. This assumption implies occurrence of discontinuities soil medium, and leads for the wall to an emergence of two dividing points of boundary conditions. The determination of the boundaries contact of the wall with the elastic half-plane, are not known in advance, is performed by iteratively way at each step set the position of dividing points of boundary conditions and the system of canonical equations of a corresponding method is written.  If tensile stresses appear in wall-base contact and/or there is overlap of the crack edges occurs, then proceeds to the next iteration. Analysis of the results shows that the bending moment and shear forces in sections of the rigid wall in a broken weighty half-plane differ slightly from the same diagrams constructed for a rigid wall in an elastic weightless half-plane. The verification of the results of analytical calculation with the results received by using the LIRA 9.6 that implements the finite element method is obtained. The calculation results for the rigid wall in an elastic weighty half-plane

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...

Ground penetrating radar antenna measurements based on plane-wave expansions

DEFF Research Database (Denmark)

Lenler-Eriksen, Hans-Rudolph; Meincke, Peter

2005-01-01

The plane-wave transmitting spectrum of the system consisting of the ground penetrating radar (GPR) antenna and the air-soil interface is measured using a loop buried in the soil. The plane-wave spectrum is used to determine various parameters characterizing the radiation of the GPR antenna...

Plane-Wave Characterization of Antennas Close to a Planar Interface

DEFF Research Database (Denmark)

Meincke, Peter; Hansen, Thorkild

2004-01-01

The plane-wave scattering matrix is used to characterize antennas that are located just above a planar interface that separates two media. The plane-wave transmitting spectrum for the field radiated downwards into the lower medium is expressed directly in terms of the current distribution of the ...

Preliminary embryological study of the radiological concept of retroperitoneal interfascial planes: what are the interfascial planes?

Science.gov (United States)

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.

Tibiofibular syndesmosis in acute ankle fractures: additional value of an oblique MR image plane

International Nuclear Information System (INIS)

Hermans, John J.; Ginai, Abida Z.; Beumer, Annechien; Moonen, Adrianus F.C.M.; Hop, Wim C.J.

2012-01-01

To evaluate the additional value of a 45 oblique MRI scan plane for assessing the anterior and posterior distal tibiofibular syndesmotic ligaments in patients with an acute ankle fracture. Prospectively, data were collected for 44 consecutive patients with an acute ankle fracture who underwent a radiograph (AP, lateral, and mortise view) as well as an MRI in both the standard three orthogonal planes and in an additional 45 oblique plane. The fractures on the radiographs were classified according to Lauge-Hansen (LH). The anterior (ATIFL) and posterior (PTIFL) distal tibiofibular ligaments, as well as the presence of a bony avulsion in both the axial and oblique planes was evaluated on MRI. MRI findings regarding syndesmotic injury in the axial and oblique planes were compared to syndesmotic injury predicted by LH. Kappa and the agreement score were calculated to determine the interobserver agreement. The Wilcoxon signed rank test and McNemar's test were used to compare the two scan planes. The interobserver agreement (κ) and agreement score [AS (%)] regarding injury of the ATIFL and PTIFL and the presence of a fibular or tibial avulsion fracture were good to excellent in both the axial and oblique image planes (κ 0.61-0.92, AS 84-95%). For both ligaments the oblique image plane indicated significantly less injury than the axial plane (p < 0.001). There was no significant difference in detection of an avulsion fracture in the axial or oblique plane, neither anteriorly (p=0.50) nor posteriorly (p=1.00). With syndesmotic injury as predicted by LH as comparison, the specificity in the oblique MR plane increased for both anterior (to 86% from 7%) and posterior (to 86% from 48%) syndesmotic injury when compared to the axial plane. Our results show the additional value of an 45 oblique MR image plane for detection of injury of the anterior and posterior distal tibiofibular syndesmoses in acute ankle fractures. Findings of syndesmotic injury in the oblique MRI plane were

Tibiofibular syndesmosis in acute ankle fractures: additional value of an oblique MR image plane

Energy Technology Data Exchange (ETDEWEB)

Hermans, John J.; Ginai, Abida Z. [Erasmus University Medical Center, Department of Radiology, Rotterdam (Netherlands); Beumer, Annechien; Moonen, Adrianus F.C.M. [Amphia Hospital, Department of Orthopaedics, Breda (Netherlands); Hop, Wim C.J. [Erasmus University Medical Center, Department of Biostatistics, Rotterdam (Netherlands)

2012-02-15

To evaluate the additional value of a 45 oblique MRI scan plane for assessing the anterior and posterior distal tibiofibular syndesmotic ligaments in patients with an acute ankle fracture. Prospectively, data were collected for 44 consecutive patients with an acute ankle fracture who underwent a radiograph (AP, lateral, and mortise view) as well as an MRI in both the standard three orthogonal planes and in an additional 45 oblique plane. The fractures on the radiographs were classified according to Lauge-Hansen (LH). The anterior (ATIFL) and posterior (PTIFL) distal tibiofibular ligaments, as well as the presence of a bony avulsion in both the axial and oblique planes was evaluated on MRI. MRI findings regarding syndesmotic injury in the axial and oblique planes were compared to syndesmotic injury predicted by LH. Kappa and the agreement score were calculated to determine the interobserver agreement. The Wilcoxon signed rank test and McNemar's test were used to compare the two scan planes. The interobserver agreement ({kappa}) and agreement score [AS (%)] regarding injury of the ATIFL and PTIFL and the presence of a fibular or tibial avulsion fracture were good to excellent in both the axial and oblique image planes ({kappa} 0.61-0.92, AS 84-95%). For both ligaments the oblique image plane indicated significantly less injury than the axial plane (p < 0.001). There was no significant difference in detection of an avulsion fracture in the axial or oblique plane, neither anteriorly (p=0.50) nor posteriorly (p=1.00). With syndesmotic injury as predicted by LH as comparison, the specificity in the oblique MR plane increased for both anterior (to 86% from 7%) and posterior (to 86% from 48%) syndesmotic injury when compared to the axial plane. Our results show the additional value of an 45 oblique MR image plane for detection of injury of the anterior and posterior distal tibiofibular syndesmoses in acute ankle fractures. Findings of syndesmotic injury in the oblique

Evaluation of an improved mixing plane interface for OpenFOAM

International Nuclear Information System (INIS)

Beaudoin, M; Page, M; Magnan, R; Nilsson, H; Jasak, H

2014-01-01

A mixing plane interface provides a circumferentially averaging rotor-stator coupling interface, which is extremely useful in practical turbomachinery simulations. It allows fundamentally transient problems to be studied in steady-state, using simplified mesh components having periodic properties, and with the help of a multiple reference frames (MRF) approach. An improved version of the mixing plane interface for the community-driven version of OpenFOAM is presented. This new version of the mixing plane introduces a per- field, user-selectable mixing option for the flow fields at the interface, including the possibility to use a mass-flow averaging algorithm for the velocity field. We show that the quality of the mass-flow transfer can be improved by a proper selection of the mixing options at the interface. This paper focuses on the evaluation of the improved mixing plane interface for various steady-state simulations of incompressible flows, applied to a simple 2D validation test case, and to more complex 3D turbomachinery cases

Deriving the effective focal plane for the CBM-RICH detector

Energy Technology Data Exchange (ETDEWEB)

Kres, Ievgenii [Wuppertal University (Germany); Collaboration: CBM-Collaboration

2016-07-01

The Compressed Baryonic Matter (CBM) experiment at the future FAIR complex will investigate the phase diagram of strongly interacting matter at high baryon density and moderate temperatures in A+A collisions from 2-11 AGeV (SIS100). A central component of the proposed detector setup is a ring imaging Cherenkov detector (RICH) using CO2 as radiator gas, and a focussing optic with a large spherical mirror. In the present design, the optimal focal plane is approximated using four individual, flat detection surfaces. However, the exact shape and position of the ideal focal plane is subject to further optimization due to effects from tilting the focussing mirror and from momentum dependant deflection of the electron tracks in the magnetic stray field. In this talk, we present a new approach to derive the effective 3-dimensional shape of the focal plane based on a set of Monte Carlo simulations, comparing the ring sharpness at each point of a preliminary focal plane as function of z-position.

Communication: Two types of flat-planes conditions in density functional theory.

Science.gov (United States)

Yang, Xiaotian Derrick; Patel, Anand H G; Miranda-Quintana, Ramón Alain; Heidar-Zadeh, Farnaz; González-Espinoza, Cristina E; Ayers, Paul W

2016-07-21

Using results from atomic spectroscopy, we show that there are two types of flat-planes conditions. The first type of flat-planes condition occurs when the energy as a function of the number of electrons of each spin, Nα and Nβ, has a derivative discontinuity on a line segment where the number of electrons, Nα + Nβ, is an integer. The second type of flat-planes condition occurs when the energy has a derivative discontinuity on a line segment where the spin polarization, Nα - Nβ, is an integer, but does not have a discontinuity associated with an integer number of electrons. Type 2 flat planes are rare-we observed just 15 type 2 flat-planes conditions out of the 4884 cases we tested-but their mere existence has implications for the design of exchange-correlation energy density functionals. To facilitate the development of functionals that have the correct behavior with respect to both fractional number of electrons and fractional spin polarization, we present a dataset for the chromium atom and its ions that can be used to test new functionals.

A three-dimensional comparison of a morphometric and conventional cephalometric midsagittal planes for craniofacial asymmetry.

Science.gov (United States)

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.

In-plane deeply-etched optical MEMS notch filter with high-speed tunability

International Nuclear Information System (INIS)

Sabry, Yasser M; Eltagoury, Yomna M; Shebl, Ahmed; Khalil, Diaa; Soliman, Mostafa; Sadek, Mohamed

2015-01-01

Notch filters are used in spectroscopy, multi-photon microscopy, fluorescence instrumentation, optical sensors and other life science applications. One type of notch filter is based on a fiber-coupled Fabry–Pérot cavity, which is formed by a reflector (external mirror) facing a dielectric-coated end of an optical fiber. Tailoring this kind of optical filter for different applications is possible because the external mirror has fewer mechanical and optical constraints. In this paper we present optical modeling and implementation of a fiber-coupled Fabry–Pérot filter based on dielectric-coated optical fiber inserted into a micromachined fiber groove facing a metallized micromirror, which is driven by a high-speed MEMS actuator. The optical MEMS chip is fabricated using deep reactive ion etching (DRIE) technology on a silicon on insulator wafer, where the optical axis is parallel to the substrate (in-plane) and the optical/mechanical components are self-aligned by the photolithographic process. The DRIE etching depth is 150 μm, chosen to increase the micromirror optical throughput and improving the out-of-plane stiffness of the MEMS actuator. The MEMS actuator type is closing-gap, while its quality factor is almost doubled by slotting the fixed plate. A low-finesse Fabry–Pérot interferometer is formed by the metallized surface of the micromirror and a cleaved end of a standard single-mode fiber, for characterization of the MEMS actuator stroke and resonance frequency. The actuator achieves a travel distance of 800 nm at a resonance frequency of 89.9 kHz. The notch filter characteristics were measured using an optical spectrum analyzer, and the filter exhibits a free spectral range up to 100 nm and a notch rejection ratio up to 20 dB around a wavelength of 1300 nm. The presented device provides batch processing and low-cost production of the filter. (paper)

Epidemic Propagation of Control Plane Failures in GMPLS Controlled Optical Transport Networks

DEFF Research Database (Denmark)

Ruepp, Sarah Renée; Fagertun, Anna Manolova

2013-01-01

In this paper, we investigate the behaviour of a dataplane-decoupled GMPLS control plane, when it is affected by failures that spread in the network in an epidemic manner. In particular, we consider network nodes to be either fully functional, or having a failed control plane, or having both...... a failed control and data plane. Through large-scale network simulation, we evaluate the effect of epidemically spreading control plane failures in terms of blocked connections requests and the amount of stranded capacity due to a dysfunctional control plane. Furthermore, we investigate the effect...... of the epidemic and the epidemic spreading intensity. In particular, networks with long epidemic durations do not necessarily result in worst performance in terms of blocked requests and capacity. Also epidemic scenarios, resulting in worst impact on the network availability does not necessarily result in worst...

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...

Flow of Dense Granular Suspensions on an Inclined Plane

Science.gov (United States)

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.

Apparatus and methods for memory using in-plane polarization

Science.gov (United States)

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.

A new form for the nucleon-nucleon potential

International Nuclear Information System (INIS)

Agarwal, B.K.

1976-01-01

The form of the internucleon force is considered. It is assumed that the nucleon-nucleon potential depends, in general, both on the distance ν and the angle theta. It is also assumed that the potential V(ν,ω) admits an analytic continuation into the complex ω-plane so that when ω=costheta is real it denotes the direction in which the potential is being determined. The analysis leads to a new parametryzation of the nucleon-nucleon potential

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.)

Stoichiometric control for heteroepitaxial growth of smooth ɛ-Ga2O3 thin films on c-plane AlN templates by mist chemical vapor deposition

Science.gov (United States)

Tahara, Daisuke; Nishinaka, Hiroyuki; Morimoto, Shota; Yoshimoto, Masahiro

2017-07-01

Epitaxial ɛ-Ga2O3 thin films with smooth surfaces were successfully grown on c-plane AlN templates by mist chemical vapor deposition. Using X-ray diffraction 2θ-ω and φ scans, the out-of-plane and in-plane epitaxial relationship was determined to be (0001) ɛ-Ga2O3 [10\\bar{1}0] ∥ (0001)AlN[10\\bar{1}0]. The gallium/oxygen ratio was controlled by varying the gallium precursor concentration in the solution. While scanning electron microscopy showed the presence of large grains on the surfaces of the films formed for low concentrations of oxygen species, no large grains were observed under stoichiometric conditions. Cathodoluminescence measurements showed a deep-level emission ranging from 1.55-3.7 eV; however, no band-edge emission was observed.

Subcostal transversus abdominis plane block can improve analgesia after laparoscopic cholecystectomy

Directory of Open Access Journals (Sweden)

Vladimir Vrsajkov

Full Text Available Abstract Background and goal of study: After laparoscopic cholecystectomy, patients have moderate pain in the early postoperative period. Some studies shown beneficial effects of subcostal transversus abdominis plane block on reducing this pain. Our goal was to investigate influence of subcostal transversus abdominis plane block on postoperative pain scores and opioid consumption. Materials and methods: We have randomized 76 patients undergoing laparoscopic cholecystectomy to receive either subcostal transversus abdominis plane block (n = 38 or standard postoperative analgesia (n = 38. First group received bilateral ultrasound guided subcostal transversus abdominis plane block with 20 mL of 0.33% bupivacaine per side before operation and tramadol 1 mg.kg−1 IV for pain breakthrough (≥6. Second group received after operation tramadol 1 mg.kg−1/6 h as standard hospital analgesia protocol. Both groups received acetaminophen 1 g/8 h IV and metamizole 2.5 g/12 h. Pain at rest was recorded for each patient using NR scale (0–10 in period of 10 min, 30 min, 2 h, 4 h, 8 h, 12 h and 16 h after the surgery. Results and discussion: We obtained no difference between groups according age, weight, intraoperative fentanyl consumption and duration of surgery. Subcostal transversus abdominis plane block significantly reduced postoperative pain scores compared to standard analgesia in all periods after surgery. Tramadol consumption was significantly lower in the subcostal transversus abdominis plane (24.29 ± 47.54 g than in the standard analgesia group (270.2 ± 81.9 g (p = 0.000. Conclusion: Our results show that subcostal transversus abdominis plane block can provide superior postoperative analgesia and reduction in opioid requirements after laparoscopic cholecystectomy.

[Subcostal transversus abdominis plane block can improve analgesia after laparoscopic cholecystectomy].

Science.gov (United States)

Vrsajkov, Vladimir; Mančić, Nedjica; Mihajlović, Dunja; Milićević, Suzana Tonković; Uvelin, Arsen; Vrsajkov, Jelena Pantić

After laparoscopic cholecystectomy, patients have moderate pain in the early postoperative period. Some studies shown beneficial effects of subcostal transversus abdominis plane block on reducing this pain. Our goal was to investigate influence of subcostal transversus abdominis plane block on postoperative pain scores and opioid consumption. We have randomized 76 patients undergoing laparoscopic cholecystectomy to receive either subcostal transversus abdominis plane block (n=38) or standard postoperative analgesia (n=38). First group received bilateral ultrasound guided subcostal transversus abdominis plane block with 20mL of 0.33% bupivacaine per side before operation and tramadol 1mg.kg -1 IV for pain breakthrough (≥6). Second group received after operation tramadol 1mg.kg -1 /6h as standard hospital analgesia protocol. Both groups received acetaminophen 1g/8h IV and metamizole 2.5g/12h. Pain at rest was recorded for each patient using NR scale (0-10) in period of 10min, 30min, 2h, 4h, 8h, 12h and 16h after the surgery. We obtained no difference between groups according age, weight, intraoperative fentanyl consumption and duration of surgery. Subcostal transversus abdominis plane block significantly reduced postoperative pain scores compared to standard analgesia in all periods after surgery. Tramadol consumption was significantly lower in the subcostal transversus abdominis plane (24.29±47.54g) than in the standard analgesia group (270.2±81.9g) (p=0.000). Our results show that subcostal transversus abdominis plane block can provide superior postoperative analgesia and reduction in opioid requirements after laparoscopic cholecystectomy. Copyright © 2017 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

Quantum-Well Infrared Photodetector (QWIP) Focal Plane Assembly

Science.gov (United States)

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.

Metal-core pad-plane development for ACTAR TPC

Science.gov (United States)

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.

Processing vertical size disparities in distinct depth planes.

Science.gov (United States)

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.

Wafer plane inspection for advanced reticle defects

Science.gov (United States)

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.

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

One-step fabrication of microfluidic chips with in-plane, adhesive-free interconnections

International Nuclear Information System (INIS)

Sabourin, D; Dufva, M; Jensen, T; Kutter, J; Snakenborg, D

2010-01-01

A simple method for creating interconnections to a common microfluidic device material, poly(methyl methacrylate) (PMMA), is presented. A press-fit interconnection is created between oversized, deformable tubing and complementary, undersized semi-circular ports fabricated into PMMA bonding surfaces by direct micromilling. Upon UV-assisted bonding the tubing is trapped in the ports of the PMMA chip and forms an integrated, in-plane and adhesive-free interconnection. The interconnections support the average pressure of 6.1 bar and can be made with small dead volumes. A comparison is made to a similar interconnection approach which uses tubing to act as a gasket between a needle and port on the microfluidic chip. (technical note)

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...

The Uniform geometrical Theory of Diffraction for elastodynamics: Plane wave scattering from a half-plane.

Science.gov (United States)

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.

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.

Hi-GAL: The Herschel Infrared Galactic Plane Survey

OpenAIRE

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...

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...

Preliminary Design and Analysis of an In-plane PRSEUS Joint

Science.gov (United States)

Lovejoy, Andrew E.; Poplawski, Steven

2013-01-01

As part of the National Aeronautics and Space Administration's (NASA's) Environmentally Responsible Aviation (ERA) program, the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) has been designed, developed and tested. However, PRSEUS development efforts to date have only addressed joints required to transfer bending moments between PRSEUS panels. Development of in-plane joints for the PRSEUS concept is necessary to facilitate in-plane transfer of load from PRSEUS panels to an adjacent structure, such as from a wing panel into a fuselage. This paper presents preliminary design and analysis of an in-plane PRSEUS joint for connecting PRSEUS panels at the termination of the rod-stiffened stringers. Design requirements are provided, the PRSEUS blade joint concept is presented, and preliminary design changes and analyses are carried out to examine the feasibility of the proposed in-plane PRSEUS blade joint. The study conducted herein focuses mainly on the PRSEUS structure on one side of the joint. In particular, the design requirements for the rod shear stress and bolt bearing stress are examined. A PRSEUS blade joint design was developed that demonstrates the feasibility of this in-plane PRSEUS joint concept to terminate the rod-stiffened stringers. The presented design only demonstrates feasibility, therefore, some areas of refinement are presented that would lead to a more optimum and realistic design.

Occlusal plane rotation: aesthetic enhancement in mandibular micrognathia.

Science.gov (United States)

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.

Flux dynamics in ultrasensitive superconducting focal planes

Data.gov (United States)

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...

Strain Paths and Fractures in Rotational Symmetric Multi Stage Single Point Incremental Forming

DEFF Research Database (Denmark)

Skjødt, Martin; Silva, M.B.; Martins, P.A.F.

2008-01-01

A multi stage strategy, which allows forming of SPIF parts with vertical walls, is investigated with emphasis on strain paths and fracture strains. Whereas downwards movement of the tool pin results in deformation close to plane strain upwards moving tool results in biaxial strains. A good correl...

Reverse-mode PSLC multi-plane optical see-through display for AR applications.

Science.gov (United States)

Liu, Shuxin; Li, Yan; Zhou, Pengcheng; Chen, Quanming; Su, Yikai

2018-02-05

In this paper we propose an optical see-through multi-plane display with reverse-mode polymer-stabilized liquid crystal (PSLC). Our design solves the problem of accommodation-vergence conflict with correct focus cues. In the reverse mode PSLC system, power consumption could be reduced to ~1/(N-1) of that in a normal mode system if N planes are displayed. The PSLC films fabricated in our experiment exhibit a low saturation voltage ~20 V rms , a high transparent-state transmittance (92%), and a fast switching time within 2 ms and polarization insensitivity. A proof-of-concept two-plane color display prototype and a four-plane monocolor display prototype were implemented.

Formation of superlattice with aligned plane orientation of colloidal PbS quantum dots

Science.gov (United States)

Mukai, Kohki; Fujimoto, Satoshi; Suetsugu, Fumimasa

2018-04-01

We investigated a method of forming a perfect quantum dot (QD) superlattice, in which each QD has the same plane orientation, by depositing colloidal PbS QDs with clear facets in solution. QD facets were controlled by adjusting the synthesis temperature. X-ray evaluation showed that the crystal orientations of the film with QDs having clear facets were aligned. The slow deposition promoted this crystal alignment. The red shift of photoluminescence wavelength caused by the film formation was larger with QDs having facets than with spherical QDs, suggesting that the connection of the wave function between QDs was better so that the quantum size effect was further reduced.

Computing half-plane and strip discrepancy of planar point sets

NARCIS (Netherlands)

Berg, de M.

1996-01-01

We present efficient algorithms for two problems concerning the discrepancy of a set S of n points in the unit square in the plane. First, we describe an algorithm for maintaining the half-plane discrepancy of S under insertions and deletions of points. The algorithm runs in O(nlogn) worst-case time

The limit of small Rossby numbers for randomly forced quasi-geostrophic equation on $\\beta$-plane

OpenAIRE

Kuksin, Sergei; Maiocchi, Alberto

2014-01-01

We consider the 2d quasigeostrophic equation on the $\\beta$-plane for the stream function $\\psi$, with dissipation and a random force: $$ (*)\\qquad (-\\Delta +K)\\psi_t - \\rho J(\\psi, \\Delta\\psi) -\\beta\\psi_x= \\langle \\text{random force}\\rangle -\\kappa\\Delta^2\\psi +\\Delta\\psi, $$ where $\\psi=\\psi(t,x,y), \\ x\\in\\mathbb{R}/2\\pi L\\mathbb{Z}, \\ y\\in \\mathbb{R}/2\\pi \\mathbb{Z}$. For typical values of the horizontal period $L$ we prove that the law of the action-vector of a solution for $(*)$ (formed...

Numerical modelling of microscopic lubricant flow in sheet metal forming. Application to plane strip drawing

DEFF Research Database (Denmark)

Carretta, Y.; Boman, R.; Bech, Jakob Ilsted

2017-01-01

This paper presents a numerical investigation of microscopic lubricant flows from the cavities to the plateaus of the surface roughness of metal sheets during forming processes. This phenomenon, called micro-plasto-hydrodynamic (MPH) lubrication, was observed experimentally in various situations...

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 ...

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...

16 CFR Figure 3 to Part 1203 - Location of Reference Plane

Science.gov (United States)

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 ...

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.

40 CFR 429.120 - Applicability; description of the sawmills and planing mills subcategory.

Science.gov (United States)

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...

Magnetic field sensor for isotropically sensing an incident magnetic field in a sensor plane

Science.gov (United States)

Pant, Bharat B. (Inventor); Wan, Hong (Inventor)

2001-01-01

A magnetic field sensor that isotropically senses an incident magnetic field. This is preferably accomplished by providing a magnetic field sensor device that has one or more circular shaped magnetoresistive sensor elements for sensing the incident magnetic field. The magnetoresistive material used is preferably isotropic, and may be a CMR material or some form of a GMR material. Because the sensor elements are circular in shape, shape anisotropy is eliminated. Thus, the resulting magnetic field sensor device provides an output that is relatively independent of the direction of the incident magnetic field in the sensor plane.

Research on spatial-variant property of bistatic ISAR imaging plane of space target

International Nuclear Information System (INIS)

Guo Bao-Feng; Wang Jun-Ling; Gao Mei-Guo

2015-01-01

The imaging plane of inverse synthetic aperture radar (ISAR) is the projection plane of the target. When taking an image using the range-Doppler theory, the imaging plane may have a spatial-variant property, which causes the change of scatter’s projection position and results in migration through resolution cells. In this study, we focus on the spatial-variant property of the imaging plane of a three-axis-stabilized space target. The innovative contributions are as follows. 1) The target motion model in orbit is provided based on a two-body model. 2) The instantaneous imaging plane is determined by the method of vector analysis. 3) Three Euler angles are introduced to describe the spatial-variant property of the imaging plane, and the image quality is analyzed. The simulation results confirm the analysis of the spatial-variant property. The research in this study is significant for the selection of the imaging segment, and provides the evidence for the following data processing and compensation algorithm. (paper)

The effects of femoral external derotational osteotomy on frontal plane alignment.

Science.gov (United States)

Nelitz, M; Wehner, T; Steiner, M; Dürselen, L; Lippacher, S

2014-11-01

Femoral osteotomies are the preferred treatment in significant torsional deformity of the femur. The influence of torsional osteotomies on frontal plane alignment is poorly understood. Therefore, the aim of the present study was to evaluate the effects of external derotational osteotomies on proximal, mid-shaft and distal levels onto frontal plane alignment. The effect of rotation around the anatomical axis of the femur on frontal plane alignment was determined with a 3D computer model, created from CT data of a right human cadaver femur. Virtual torsional osteotomies of 10°, 20° and 30° were performed at proximal, mid-shaft and distal levels under five antecurvatum angles of the femur. The change of the frontal plane alignment was expressed by the mechanical lateral femoral angle. Proximal derotational osteotomies resulted in an increased mechanical lateral distal femoral angle (mLDFA) of 0.8°-2.6° for 10°, of 1.6°-5.1° for 20° and of 2.3-7.9° for 30° derotational osteotomy, indicating an increased varus angulation. Supracondylar derotational osteotomy resulted in a decreased mLDFA of -0.1° to -1.7° for 10°, of -0.2 to -3.7° for 20° and of -0.7 to -6.9° for 30° derotational osteotomy, indicating an increased valgus angulation. The effect increased with the amount of torsional correction and virtually increased antecurvatum angles. Mid-shaft torsional osteotomies had the smallest effect on frontal plane alignment. This three-dimensional computer model study demonstrates the relationship between femoral torsional osteotomies and frontal plane alignment. Proximal external derotational osteotomies tend to result in an increased varus angulation, whilst distal external derotational osteotomies tend to result in an increased valgus angulation. As a clinical consequence, torsional osteotomies have an increased risk of unintentional implications on frontal plane alignment.

Performance of an Achromatic Focal Plane Mask for Exoplanet Imaging Coronagraphy

Science.gov (United States)

Newman, Kevin; Belikov, Ruslan; Pluzhnik, Eugene; Balasubramanian, Kunjithapatham; Wilson, Dan

2014-01-01

Coronagraph technology combined with wavefront control is close to achieving the contrast and inner working angle requirements in the lab necessary to observe the faint signal of an Earth-like exoplanet in monochromatic light. An important remaining technological challenge is to achieve high contrast in broadband light. Coronagraph bandwidth is largely limited by chromaticity of the focal plane mask, which is responsible for blocking the stellar PSF. The size of a stellar PSF scales linearly with wavelength; ideally, the size of the focal plane mask would also scale with wavelength. A conventional hard-edge focal plane mask has a fixed size, normally sized for the longest wavelength in the observational band to avoid starlight leakage. The conventional mask is oversized for shorter wavelengths and blocks useful discovery space. Recently we presented a solution to the size chromaticity challenge with a focal plane mask designed to scale its effective size with wavelength. In this paper, we analyze performance of the achromatic size-scaling focal plane mask within a Phase Induced Amplitude Apodization (PIAA) coronagraph. We present results from wavefront control around the achromatic focal plane mask, and demonstrate the size-scaling effect of the mask with wavelength. The edge of the dark zone, and therefore the inner working angle of the coronagraph, scale with wavelength. The achromatic mask enables operation in a wider band of wavelengths compared with a conventional hard-edge occulter.

Alignment in the transverse plane, but not sagittal or coronal plane, affects the risk of recurrent patella dislocation.

Science.gov (United States)

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

Communication: Two types of flat-planes conditions in density functional theory

Energy Technology Data Exchange (ETDEWEB)

Yang, Xiaotian Derrick; Patel, Anand H. G.; González-Espinoza, Cristina E.; Ayers, Paul W. [Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario LBS 4M1 (Canada); Miranda-Quintana, Ramón Alain [Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario LBS 4M1 (Canada); Laboratory of Computational and Theoretical Chemistry, Faculty of Chemistry, University of Havana, Havana (Cuba); Heidar-Zadeh, Farnaz [Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario LBS 4M1 (Canada); Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3), 9000 Gent (Belgium); Center for Molecular Modeling, Ghent University, Technologiepark 903, 9052 Zwijnaarde (Belgium)

2016-07-21

Using results from atomic spectroscopy, we show that there are two types of flat-planes conditions. The first type of flat-planes condition occurs when the energy as a function of the number of electrons of each spin, N{sub α} and N{sub β}, has a derivative discontinuity on a line segment where the number of electrons, N{sub α} + N{sub β}, is an integer. The second type of flat-planes condition occurs when the energy has a derivative discontinuity on a line segment where the spin polarization, N{sub α} – N{sub β}, is an integer, but does not have a discontinuity associated with an integer number of electrons. Type 2 flat planes are rare—we observed just 15 type 2 flat-planes conditions out of the 4884 cases we tested—but their mere existence has implications for the design of exchange-correlation energy density functionals. To facilitate the development of functionals that have the correct behavior with respect to both fractional number of electrons and fractional spin polarization, we present a dataset for the chromium atom and its ions that can be used to test new functionals.

Three-dimensional volumetric display by inclined-plane scanning

Science.gov (United States)

Miyazaki, Daisuke; Eto, Takuma; Nishimura, Yasuhiro; Matsushita, Kenji

2003-05-01

A volumetric display system based on three-dimensional (3-D) scanning that uses an inclined two-dimensional (2-D) image is described. In the volumetric display system a 2-D display unit is placed obliquely in an imaging system into which a rotating mirror is inserted. When the mirror is rotated, the inclined 2-D image is moved laterally. A locus of the moving image can be observed by persistence of vision as a result of the high-speed rotation of the mirror. Inclined cross-sectional images of an object are displayed on the display unit in accordance with the position of the image plane to observe a 3-D image of the object by persistence of vision. Three-dimensional images formed by this display system satisfy all the criteria for stereoscopic vision. We constructed the volumetric display systems using a galvanometer mirror and a vector-scan display unit. In addition, we constructed a real-time 3-D measurement system based on a light section method. Measured 3-D images can be reconstructed in the 3-D display system in real time.

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.

Pull-out test of stud bolts embedded in concrete under an in-plane force

International Nuclear Information System (INIS)

Inada, Y.; Saito, H.; Torita, H.; Takiguchi, K.; Ibe, Y.; Taira, T.

1995-01-01

There are many steel plates with stud bolts embedded in the R C walls of a nuclear reactor building to support equipment and piping. Under a earthquake, the steel plates are submitted to an out-of-plane force due to the inertia force acting upon equipment and piping. Furthermore, the walls are submitted to an in-plane force, and cracks may occur. A large number of experimental studies have been carried out on the pull-out strength of stud bolts embedded in concrete. Few studies have been performed to understand the strength of stud bolts embedded in concrete under an in-plane force and, further, not any one on the strength for concrete under in-plane force simultaneously to stud bolts under out-of-plane force. This paper describes a test performed to understand the pull-out strength determined by this interaction of in-plane and out-of-plane forces. (author). 5 refs., 9 figs., 5 tabs