Craniofacial Reconstruction Using Rational Cubic Ball Curves
Majeed, Abdul; Mt Piah, Abd Rahni; Gobithaasan, R. U.; Yahya, Zainor Ridzuan
2015-01-01
This paper proposes the reconstruction of craniofacial fracture using rational cubic Ball curve. The idea of choosing Ball curve is based on its robustness of computing efficiency over Bezier curve. The main steps are conversion of Digital Imaging and Communications in Medicine (Dicom) images to binary images, boundary extraction and corner point detection, Ball curve fitting with genetic algorithm and final solution conversion to Dicom format. The last section illustrates a real case of craniofacial reconstruction using the proposed method which clearly indicates the applicability of this method. A Graphical User Interface (GUI) has also been developed for practical application. PMID:25880632
Kauffman bracket of plane curves
NASA Astrophysics Data System (ADS)
Chmutov, S.; Goryunov, V.
1996-12-01
We lower the Kauffman bracket for links in a solid torus (see [16]) to generic plane fronts. It turns out that the bracket can be entirely defined in terms of a front itself without using the Legendrian lifting. We show that all the coefficients of the lowered bracket are in fact Vassilev type invariants of Arnold's J +-theory [3, 4]. We calculate their weight systems. As a corollary we obtain that the first coefficient is essentially the quantum deformation of the Bennequin invariant introduced recently by M. Polyak [19].
Finding Rational Parametric Curves of Relative Degree One or Two
ERIC Educational Resources Information Center
Boyles, Dave
2010-01-01
A plane algebraic curve, the complete set of solutions to a polynomial equation: f(x, y) = 0, can in many cases be drawn using parametric equations: x = x(t), y = y(t). Using algebra, attempting to parametrize by means of rational functions of t, one discovers quickly that it is not the degree of f but the "relative degree," that describes how…
Finding Rational Parametric Curves of Relative Degree One or Two
ERIC Educational Resources Information Center
Boyles, Dave
2010-01-01
A plane algebraic curve, the complete set of solutions to a polynomial equation: f(x, y) = 0, can in many cases be drawn using parametric equations: x = x(t), y = y(t). Using algebra, attempting to parametrize by means of rational functions of t, one discovers quickly that it is not the degree of f but the "relative degree," that describes how…
Differentialless geometry of plane curves
NASA Astrophysics Data System (ADS)
Latecki, Longin J.; Rosenfeld, Azriel
1997-10-01
We introduce a class of planar arcs and curves, called tame arcs, which is general enough to describe the boundaries of planar real objects. A tame arc can have smooth parts as well as sharp corners; thus a polygonal arc is tame. On the other hand, this class of arcs is restrictive enough to rule out pathological arcs which have infinitely many inflections or which turn infinitely often: a tame arc can have only finitely many inflections, and its total absolute turn must be finite. In order to relate boundary properties of discrete objects obtained by segmenting digital images to the corresponding properties of their continuous originals, the theory of tame arcs is based on concepts that can be directly transferred from the continuous to the discrete domain. A tame arc is composed of a finite number of supported arcs. We define supported digital arcs and motivate their definition by the fact that hey can be obtained by digitizing continuous supported arcs. Every digital arc is tame, since it contains a finite number of points, and therefore it can be decomposed into a finite number of supported digital arcs.
Solid-state curved focal plane arrays
NASA Technical Reports Server (NTRS)
Nikzad, Shouleh (Inventor); Hoenk, Michael (Inventor); Jones, Todd (Inventor)
2010-01-01
The present invention relates to curved focal plane arrays. More specifically, the present invention relates to a system and method for making solid-state curved focal plane arrays from standard and high-purity devices that may be matched to a given optical system. There are two ways to make a curved focal plane arrays starting with the fully fabricated device. One way, is to thin the device and conform it to a curvature. A second way, is to back-illuminate a thick device without making a thinned membrane. The thick device is a special class of devices; for example devices fabricated with high purity silicon. One surface of the device (the non VLSI fabricated surface, also referred to as the back surface) can be polished to form a curved surface.
Microorganism billiards in closed plane curves
NASA Astrophysics Data System (ADS)
Krieger, Madison
Recent experiments and numerical simulations have demonstrated that many species of microorganisms reflect aspecularly from a solid surface -- due to steric and hydrodynamic interactions with the wall, their outgoing angle is fixed and independent of the angle of incidence. Motivated by these results, we discuss theory and computation of the ``aspecular billiard'', a modification of the classical billiard in which the outgoing angle is constant. We restrict our attention to closed plane curves, focusing on three canonical examples: the ellipse, the Bunimovich stadium, and the Sinai billiard. These systems can have a rich array of orbits, and the Lyapunov exponent is shown to be dependent on the billiard geometry and the outgoing angle. We apply these results to the design of tunable passive sorting mechanisms.
Source localization using rational approximation on plane sections
NASA Astrophysics Data System (ADS)
Clerc, M.; Leblond, J.; Marmorat, J.-P.; Papadopoulo, T.
2012-05-01
In functional neuroimaging, a crucial problem is to localize active sources within the brain non-invasively, from knowledge of electromagnetic measurements outside the head. Identification of point sources from boundary measurements is an ill-posed inverse problem. In the case of electroencephalography (EEG), measurements are only available at electrode positions, the number of sources is not known in advance and the medium within the head is inhomogeneous. This paper presents a new method for EEG source localization, based on rational approximation techniques in the complex plane. The method is used in the context of a nested sphere head model, in combination with a cortical mapping procedure. Results on simulated data prove the applicability of the method in the context of realistic measurement configurations.
Projecting diffusion along the normal bundle of a plane curve
Valero-Valdés, Carlos; Herrera-Guzmán, Rafael
2014-05-15
The purpose of this paper is to provide new formulas for the effective diffusion coefficient of a generalized Fick-Jacob's equation obtained by projecting the two-dimensional diffusion equation along the normal directions of an arbitrary curve on the plane.
Projecting diffusion along the normal bundle of a plane curve
NASA Astrophysics Data System (ADS)
Valero-Valdés, Carlos; Herrera-Guzmán, Rafael
2014-05-01
The purpose of this paper is to provide new formulas for the effective diffusion coefficient of a generalized Fick-Jacob's equation obtained by projecting the two-dimensional diffusion equation along the normal directions of an arbitrary curve on the plane.
Integrable mappings of the plane preserving biquadratic invariant curves
NASA Astrophysics Data System (ADS)
Iatrou, Apostolos; Roberts, John A. G.
2001-08-01
We provide a general framework to construct integrable mappings of the plane that preserve a one-parameter family B(x,y,K) of biquadratic invariant curves where parametrization by K is very general. These mappings are reversible by construction (i.e. they are the composition of two involutions) and can be shown to be measure preserving. They generalize integrable maps previously given by McMillan and Quispel, Roberts and Thompson. By considering a transformation of the case of the symmetric biquadratic to a canonical form, we provide a normal form for the symmetric integrable map acting on each invariant curve. We give a Lax pair for a large subclass of our symmetric integrable maps, including at least a 10-parameter subfamily of the 12-parameter symmetric Quispel-Roberts-Thompson maps.
Curved-Focal-Plane Arrays Using Deformed-Membrane Photodetectors
NASA Technical Reports Server (NTRS)
Nikzad, Shouleh; Jones, Todd
2004-01-01
A versatile and simple approach to the design and fabrication of curved-focal-plane arrays of silicon-based photodetectors is being developed. This approach is an alternative to the one described in "Curved Focal-Plane Arrays Using Back- Illuminated High-Purity Photodetectors" (NPO-30566), NASA Tech Briefs, Vol. 27, No. 10 (October 2003), page 10a. As in the cited prior article, the basic idea is to improve the performance of an imaging instrument and simplify the optics needed to obtain a given level of performance by making an image sensor (in this case, an array of photodetectors) conform to a curved focal surface, instead of designing the optics to project an image onto a flat focal surface. There is biological precedent for curved-focal-surface designs: retinas - the image sensors in eyes - conform to the naturally curved focal surfaces of eye lenses. The present approach is applicable to both front-side- and back-side-illuminated, membrane photodetector arrays and is being demonstrated on charge-coupled devices (CCDs). The very-large scale integrated (VLSI) circuitry of such a CCD or other array is fabricated on the front side of a silicon substrate, then the CCD substrate is attached temporarily to a second substrate for mechanical support, then material is removed from the back to obtain the CCD membrane, which typically has a thickness between 10 and 20 m. In the case of a CCD designed to operate in back-surface illumination, delta doping can be performed after thinning to enhance the sensitivity. This approach is independent of the design and method of fabrication of the front-side VLSI circuitry and does not involve any processing of a curved silicon substrate. In this approach, a third substrate would be prepared by polishing one of its surfaces to a required focal-surface curvature. A CCD membrane fabricated as described above would be pressed against, deformed into conformity with, and bonded to, the curved surface. The technique used to press and
A plane rational map with Chebyshev-like dynamics
NASA Astrophysics Data System (ADS)
Liu, Han
This paper concerns a specific rational map of two complex variables whose dynamics are closely related to those of the well known one variable Chebyshev map. The goal is to obtain a complete description of the dynamics of the map, something that is rarely possible for such examples and then go on to study dynamics of some nearby perturbations.
Surface design by blending rational Bézier curves and surfaces
NASA Astrophysics Data System (ADS)
Ismail, Solehah Jamilah; Ali, Jamaludin Md.
2014-07-01
Blending method can be used to design many interesting curves, surfaces and objects. Some types of blending methods are linear, quadratic and cubic blending. These methods have similar concept to Bézier because the blending method only touch the first and last curve or surface without touching the intermediate curves or surfaces. These methods produce a blended curve, surface or object by blending several selected curves or surfaces. Curve blending methods will generate some interesting blended curves, surfaces or objects. Surface blending methods can produce some blended surfaces or object. Rational Bézier curves will be used as a base curve. The positions of control points and the values of weights of the curves play an important role in generating the right shapes. The concept of blending functions with Cn continuity will be discussed. Blending function will be used and the blended curves or surfaces with Gn continuity will be generated.
Geometric Structure of 3D Spinal Curves: Plane Regions and Connecting Zones
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
Interfacial Refraction Through Curved and Plane-Layered Media
Kehoe, A.B.
2001-07-17
Two laser beam tracing codes, AXIAL and CYLINDER, have been written to determine a laser beam path through plane and cylindrical interfaces. For cylindrical interfaces, an equation set was derived which describes the path of the laser beam. For plane interfaces, it was not possible to derive a single equation set. Instead, it was necessary to divide the domain up into small elements or regions. The laser beam path was then determined by calculating the path of the laser beam through each region. AXIAL and CYLINDER can be used to determine where an LDA should be positioned so that velocity measurements can be made at a specified point.
Rational quadratic Bézier curve fitting by simulated annealing technique
NASA Astrophysics Data System (ADS)
Mohamed, Najihah; Abd Majid, Ahmad; Mt Piah, Abd Rahni
2013-04-01
A metaheuristic algorithm, which is an approximation method called simulated annealing is implemented in order to have the best rational quadratic Bézier curve from a given data points. This technique is used to minimize sum squared errors in order to improve the middle control point position and the value of weight. As a result, best fitted rational quadratic Bézier curve and its mathematical function that represents all the given data points is obtained. Numerical and graphical examples are also presented to demonstrate the effectiveness and robustness of the proposed method.
Dallaston, Michael C.
2016-01-01
Motivated by a problem from fluid mechanics, we consider a generalization of the standard curve shortening flow problem for a closed embedded plane curve such that the area enclosed by the curve is forced to decrease at a prescribed rate. Using formal asymptotic and numerical techniques, we derive possible extinction shapes as the curve contracts to a point, dependent on the rate of decreasing area; we find there is a wider class of extinction shapes than for standard curve shortening, for which initially simple closed curves are always asymptotically circular. We also provide numerical evidence that self-intersection is possible for non-convex initial conditions, distinguishing between pinch-off and coalescence of the curve interior. PMID:26997898
Dallaston, Michael C; McCue, Scott W
2016-01-01
Motivated by a problem from fluid mechanics, we consider a generalization of the standard curve shortening flow problem for a closed embedded plane curve such that the area enclosed by the curve is forced to decrease at a prescribed rate. Using formal asymptotic and numerical techniques, we derive possible extinction shapes as the curve contracts to a point, dependent on the rate of decreasing area; we find there is a wider class of extinction shapes than for standard curve shortening, for which initially simple closed curves are always asymptotically circular. We also provide numerical evidence that self-intersection is possible for non-convex initial conditions, distinguishing between pinch-off and coalescence of the curve interior.
NASA Technical Reports Server (NTRS)
Slater, David C.; Morgan, Jeffrey S.; Timothy, J. Gethyn
1989-01-01
The presently performance-evaluated format, in which a high-gain curved-channel microchannel plate (M2MCP) has a spherical concave input face and a plane output face, allows the input face of the MCP (1) to match such curved focal surfaces as that of a Rowland-circle spectrometer mounting, while (2) having a high-resolution plane readout array in proximity focus with the output face. This MCP has been evaluated in a discrete-anode multicathode microchannel array detector system. The saturated modal gain was found to be inversely proportional to the length/diameter ratio of the channels and directly proportional to the applied MCP voltage.
A study of a collision avoidance system mounted on a curved ground plane
NASA Technical Reports Server (NTRS)
Law, P. H.; Burnside, W. D.; Rojas, R. G.
1986-01-01
Research conducted on a traffic advisory and collision avoidance system (TCAS 2) mounted on a curved ground plane is described. It is found that a curved finite ground plane can be used as a good simulation model for the fuselage of an aircraft but may not be good enough to model a whole aircraft due to the shadowing of the vertical stabilizer, wings, etc. The surface curvature of this curved disc significantly affects the monopulse characteristics in the azimuth plane but not as much in the elevation plane. These variations of the monopulse characteristics verify the need of a lookup table for the 64 azimuth beam positions. The best location of a TCAS 2 array on a Boeing 737 is to move it as far from the vertical stabilizer as possible.
Michałowska-Kaczmarczyk, Anna Maria; Asuero, Agustin G; Martin, Julia; Alonso, Esteban; Jurado, Jose Marcos; Michałowski, Tadeusz
2014-12-01
Rational functions of the Padé type are used for the calibration curve (CCM), and standard addition (SAM) methods purposes. In this paper, the related functions were applied to results obtained from the analyses of (a) nickel with use of FAAS method, (b) potassium according to FAES method, and (c) salicylic acid according to HPLC-MS/MS method. A uniform, integral criterion of nonlinearity of the curves, obtained according to CCM and SAM, is suggested. This uniformity is based on normalization of the approximating functions within the frames of a unit area. Copyright © 2014 Elsevier B.V. All rights reserved.
Reparameterization invariant distance on the space of curves in the hyperbolic plane
NASA Astrophysics Data System (ADS)
Le Brigant, Alice; Arnaudon, Marc; Barbaresco, Frédéric
2015-01-01
This paper focuses on the study of time-varying paths in the two-dimensional hyperbolic space, and its aim is to define a reparameterization invariant distance on the space of such paths. We adapt the geodesical distance on the space of parameterized plane curves given by Bauer et al. in [1] to the space Imm([0,1],H ) of parameterized curves in the hyperbolic plane. We present a definition which enables to evaluate the difference between two curves, and show that it satisfies the three properties of a metric. Unlike the distance of Bauer et al., the distance obtained takes into account the positions of the curves, and not only their shapes and parameterizations, by including the distance between their origins.
Stretch bending - the plane within the sheet where strains reach the forming limit curve
NASA Astrophysics Data System (ADS)
Neuhauser, F. M.; Terrazas, O. R.; Manopulo, N.; Hora, P.; Van Tyne, C. J.
2016-11-01
Finite element analysis (FEA) was used to model the angular stretch bend test, where a strip of sheet metal is locked at both ends and a tool with a radius stretches and bends the center of the strip until failure. The FEA program used in the study was Abaqus. The FEA model was verified by experimental work using a dual phase steel (DP600) and with a simplified analytical analysis. The FEA model was used to simulate the experimental test for various frictional conditions and various radii of an upward moving tool. The primary objective of the study was to evaluate the concave-side rule, which states that during stretch bending the forming limit occurs when the strains on the concave surface plane of the bent sheet (i.e. bottom plane) reach the forming limit curve (FLC). The verification with experimental data indicates that the FEA model represents the process very well. Only conditions where failure occurred on or near the tooling are included in the results. The FEA simulations showed that the actual forming limit of the sheet occurs when the strains on the bottom plane of the sheet (i.e. concave side of the bend) reach the forming limit curve for high friction and small tool radii. For lower friction and for larger tool radii the actual forming limit occurs when strains on other planes in the sheet (i.e. mid planes or top surface plane) reach the forming limit curve. The implications of these results suggest that care must be taken in assessing forming operations when both stretch and bending occur. Although it is known that the FLC cannot predict the forming limit for small bend radii, the common assumption that the forming limit occurs when the strains for the middle thickness plane of the sheet reach the forming limit curve or that the concave side rule is often made. Understanding the limits of this assumption needs to be carefully and critically evaluated.
Plane stress yield function described by 3rd-degree spline curve and its application
NASA Astrophysics Data System (ADS)
Aamaishi, Toshiro; Tsutamori, Hideo; Iizuka, Eiji; Sato, Kentaro; Ogihara, Yuki; Matsui, Yohei
2016-08-01
In this study, a plane stress yield function which is described by 3rd-degree spline curve is proposed. This yield function can predict a material anisotropy with flexibility and consider evolution of anisotropy in terms of both r values and stresses. As an application, hole expanding simulation results are shown to discuss accuracy of the proposed yield function.
Youssef, A; Cavalera, M; Pacella, G; Salsi, G; Morganelli, G; Montaguti, E; Cataneo, I; Pilu, G; Rizzo, N
2016-09-19
Caudal distension of the female pelvic floor is common and results in perineal descent and a caudally curved levator hiatus (warping). Image reconstruction of the pelvic floor using currently available ultrasound techniques involves a linear approach (flat-plane reconstruction). We aimed to evaluate the feasibility, reproducibility and potential usefulness of a new three-dimensional (3D) technique capable of reconstructing a curved plane of the levator hiatus. Primiparous women were recruited to undergo a 3D/four-dimensional transperineal ultrasound examination 3-6 months after delivery. Levator ani muscle warping was evaluated on Valsalva maneuver by measuring the distance between the plane extending from the pubic rami to the anorectal angle and the plane of minimal hiatal dimensions on the coronal plane. Warping distance was used to reconstruct a curved plane of the levator hiatus using the curved OmniView volume contrast imaging (VCI) technique (C-OV). Intra- and interobserver reproducibility of the C-OV technique were assessed, as was intermethod agreement between the C-OV technique and the linear OmniView-VCI (L-OV) technique, for the measurement of levator hiatal area on Valsalva maneuver. Measurement of the levator hiatal area using C-OV was feasible in all 84 women recruited. The warping distance ranged from -3.5 to 9.7 mm, confirming that the 1-2-cm slice thickness traditionally used for linear reconstruction was adequate for proper assessment of levator hiatal area in our population. C-OV showed excellent intra- and interobserver reproducibility, as well as excellent agreement with the L-OV technique for measuring levator hiatal area. No systematic difference was demonstrated in any of the reproducibility studies performed. 3D reconstruction of the warped levator hiatal plane is feasible and highly reproducible. In our population, reconstruction of a curved plane to correct for levator hiatal warping did not offer any benefit over the traditionally
IMAGE-PLANE ANALYSIS OF n-POINT-MASS LENS CRITICAL CURVES AND CAUSTICS
Danek, Kamil; Heyrovský, David E-mail: heyrovsky@utf.mff.cuni.cz
2015-06-10
The interpretation of gravitational microlensing events caused by planetary systems or multiple stars is based on the n-point-mass lens model. The first planets detected by microlensing were well described by the two-point-mass model of a star with one planet. By the end of 2014, four events involving three-point-mass lenses had been announced. Two of the lenses were stars with two planetary companions each; two were binary stars with a planet orbiting one component. While the two-point-mass model is well understood, the same cannot be said for lenses with three or more components. Even the range of possible critical-curve topologies and caustic geometries of the three-point-mass lens remains unknown. In this paper we provide new tools for mapping the critical-curve topology and caustic cusp number in the parameter space of n-point-mass lenses. We perform our analysis in the image plane of the lens. We show that all contours of the Jacobian are critical curves of re-scaled versions of the lens configuration. Utilizing this property further, we introduce the cusp curve to identify cusp-image positions on all contours simultaneously. In order to track cusp-number changes in caustic metamorphoses, we define the morph curve, which pinpoints the positions of metamorphosis-point images along the cusp curve. We demonstrate the usage of both curves on simple two- and three-point-mass lens examples. For the three simplest caustic metamorphoses we illustrate the local structure of the image and source planes.
Designing of skull defect implants using C1 rational cubic Bezier and offset curves
NASA Astrophysics Data System (ADS)
Mohamed, Najihah; Majid, Ahmad Abd; Piah, Abd Rahni Mt; Rajion, Zainul Ahmad
2015-05-01
Some of the reasons to construct skull implant are due to head trauma after an accident or an injury or an infection or because of tumor invasion or when autogenous bone is not suitable for replacement after a decompressive craniectomy (DC). The main objective of our study is to develop a simple method to redesign missing parts of the skull. The procedure begins with segmentation, data approximation, and estimation process of the outer wall by a C1 continuous curve. Its offset curve is used to generate the inner wall. A metaheuristic algorithm, called harmony search (HS) is a derivative-free real parameter optimization algorithm inspired from the musical improvisation process of searching for a perfect state of harmony. In this study, data approximation by a rational cubic Bézier function uses HS to optimize position of middle points and value of the weights. All the phases contribute significantly in making our proposed technique automated. Graphical examples of several postoperative skulls are displayed to show the effectiveness of our proposed method.
Curved Focal-Plane Arrays Using Back-Illuminated High-Purity Photodetectors
NASA Technical Reports Server (NTRS)
Nikzad, Shouleh; Hoenk, Michael E.
2003-01-01
Curved-focal-plane arrays of back-illuminated silicon-based photodetectors are being developed. The basic idea is to improve the performance of an imaging instrument and simplify the optics needed to obtain a given level of performance by making an image sensor (e.g., a photographic film or an array of photodetectors) conform to a curved focal surface, instead of following the customary practice of designing the optics to project an image onto a flat focal surface. Eyes are natural examples of optical systems that have curved focal surfaces on which image sensors (retinas) are located. One prior approach to implementation of this concept involves the use of curved-input-surface microchannel plates as arrays of photodetectors. In comparison with microchannel plates, these curved-focal-plane arrays would weigh less, operate at much lower voltages, and consume less power. It should also be possible to fabricate the proposed devices at lower cost. It would be possible to fabricate an array of photodetectors and readout circuitry in the form of a very-large-scale integrated (VLSI) circuit on a curved focal surface, but it would be difficult and expensive to do so. In a simple and inexpensive alternate approach, a device (see figure) would have (1) a curved back surface, onto which light would be focused; and (2) a flat front surface, on which VLSI circuitry would be fabricated by techniques that are well established for flat surfaces. The device would be made from ultrapure silicon, in which it is possible to form high-resistivity, thick photodetectors that are fully depleted through their thicknesses. (As used here, "thick means having a thickness between a fraction of a millimeter and a few millimeters.) The back surface would be polished to the curvature of the focal surface of the intended application. To enable the collection of charge carriers excited by photons near the back surface or in the bulk of the device, it would be necessary to form a transparent or
NASA Technical Reports Server (NTRS)
Emery, J. D.
1985-01-01
Two topics in topology, the comparison of plane curves and faces on geometric models, are discussed. With regard to the first problem, a curve is defined to be a locus of points without any underlying parameterization. A metric on a class of plane curves is defined, a finite computation of this metric is given for the case of piecewise linear curves, and it is shown how to approximate curves that have bounded curvature by piecewise linear curves. In this way a bound on the distance between two curves can be computed. With regard to the second problem, the questions to be discussed are under what circumstances do geometrical faces make sense; how can they be explicity defined; and when are these geometrical faces homeomorphic to the realization of the abstract (topological) face.
Hemispherical curved monolithic cooled and uncooled infrared focal plane arrays for compact cameras
NASA Astrophysics Data System (ADS)
Tekaya, Kevin; Fendler, Manuel; Dumas, Delphine; Inal, Karim; Massoni, Elisabeth; Gaeremynck, Yann; Druart, Guillaume; Henry, David
2014-06-01
InfraRed (IR) sensor systems like night vision goggles, missile approach warning systems and telescopes have an increasing interest in decreasing their size and weight. At the same time optical aberrations are always more difficult to optimize with larger Focal Plane Arrays (FPAs) and larger field of view. Both challenges can now take advantage of a new optical parameter thanks to flexible microelectronics technologies: the FPA spherical curvature. This bio-inspired approach can correct optical aberrations and reduce the number of lenses in camera conception. Firstly, a new process to curve thin monolithic devices has been applied to uncooled microbolometers FPAs. A functional 256×320 25μm pitch (roughly 1cm2) uncooled FPA has been thinned and curved. Its electrical response showed no degradation after our process (variation of less than 2.3% on the response). Then a two lenses camera with a curved FPA is designed and characterized in comparison with a two lenses camera with a flat FPA. Their Modulation Transfer Functions (MTFs) show clearly an improvement in terms of beams dispersion. Secondly, a new process to fabricate monolithic cooled flip-chip MCT-IRCMOS FPAs was developed leading to the first spherical cooled IR FPA: with a radius of 550 mm. Other radii are achieved. A standard opto-electrical characterization at 80 K of the imager shows no additional short circuit and no mean response alteration compared to a standard IRCMOS shown in reference. Noise is also studied with a black body between 20 and 30°C.
Xu, Guan; Sun, Lina; Li, Xiaotao; Su, Jian; Hao, Zhaobing; Lu, Xue
2014-09-08
We demonstrate a global calibration method for the laser plane using a 3D calibration board to generate the two horizontal coordinates and a height gauge to generate the height coordinate of the point in the laser plane. A sigmoid-Gaussian function for the candidate centers is employed to normalize the eigenvalues of the Hessian matrix to prevent centers missing or muti-centers. Then camera calibration and laser plane calibration are accomplished at the same time. Finally the reconstructed 3D points are transformed to the horizontal plane by the forward process that involves one translation and two rotations. The parametric equation of the 3D curve is reconstructed by the inverse process that performs on the 2D fitting curve.
Computation of bound orbits in the plane of a galaxy with a flat rotation curve
NASA Astrophysics Data System (ADS)
Bacon, M. E.; Sharrar, Amber
2010-05-01
A standard topic in an advanced undergraduate classical mechanics course is the determination of the orbits in a gravitational field. In the present paper we report on the calculation of bound orbits in the gravitational field of a spiral galaxy. Calculations such as these could serve to focus attention on an area of cutting edge astrophysics and could serve as an instructive exercise for advanced undergraduates. In the computations given in this paper, use is made of real data on the flat rotation curve of NGC 3198 obtained by Begeman et al (van Albada et al 1985 Astrophys. J. 295 305-13 Begeman 1989 Astron. Astrophys. 223 47-60 Begeman 1987 PhD Thesis University of Groningen http://irs.ub.rug.nl/ppn/291578543), and a fitting of that data to a theoretical model outlined in a previous paper (Bacon and Sharrar 2010 Am. J. Phys. at press). The galaxy is modelled as a thin exponential disc of baryonic matter combined with a spherically symmetric dark matter halo. The bound orbits in the plane of the galaxy are investigated. The computations are carried out using an icon-driven systems-modelling program that avoids the need for extensive programming expertise. The range of orbits investigated includes bound circular orbits and bound closed and open orbits that precess. The bound closed and open orbits are bounded by circles generated by the loci of the apsides of the orbit.
NASA Astrophysics Data System (ADS)
Usuki, Tsuneo
2013-09-01
The moduli of conventional elastic structural materials are extended to one of the viscoelastic materials through a modification whereby the dynamic moduli converge to the static moduli of elasticity as the fractional order approaches zero. By plotting phase velocity curves and group velocity curves of plane waves and Rayleigh surface wave for a viscoelastic material (polyvinyl chloride foam), the influence of the fractional order of viscoelasticity is examined. The phase and group velocity curves in the high frequency range were derived for longitudinal, transverse, and Rayleigh waves inherent to the viscoelastic material. In addition, the equation for the phase velocity was mathematically derived on the complex plane, too, and graphically illustrated. A phenomenon was found that, at the moment when the fractional order of the time derivative reaches an integer value 1, the curve on the complex plane becomes completely different, exhibiting snap-through behavior. We examined the mechanism of the snap-through mathematically. Numerical calculation examples were solved, and good agreement was confirmed between the numerical calculation and the analytical expression mentioned above. From the results of the numerical example, regularities were derived for the absolute value of the complex phase and group velocities on the complex plane.
Atmaca, Halil; Inanmaz, Mustafa Erkan; Bal, Emre; Caliskan, Islam; Kose, Kamil Cagri
2014-10-01
Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional (3D) deformity of the spine involving deviations in the frontal plane, modifications of the sagittal profile, and rotations in the transverse plane. Although Lenke classification system is based on 2D radiographs and includes sagittal thoracic and coronal lumbar modifiers, Lenke et al. suggested inclusion of axial thoracic and lumbar modifiers in the analysis. To analyze axial plane of Lenke 1A curves to identify curve characteristics. Retrospective study. Seventy patients (49 women, 21 men) with Lenke Type 1A idiopathic scoliosis were analyzed. Coronal, sagittal, and axial parameters were measured from plain radiographs that were obtained at initial medical examination of the patients. Coronal and sagittal plane and whole spine segmental vertebra rotations from thoracic 1 to lumbar 5 were evaluated in 70 AIS patients with Lenke 1A curves by using Drerup method. Three different subgroups were identified according to magnitude and direction of lower end vertebra (LEV) rotation. In Group 1 (Lenke 1A1), the direction of LEV rotation was same with other vertebrae in the main curve and the magnitude of the LEV rotation was less than -0.5°. In Group 2 (Lenke 1A2), the rotation of LEV was between -0.5° and 0.5° and so was accepted as neutral. In Group 3 (Lenke 1A3), the rotation of LEV had opposite direction with vertebrae in the main curve and the magnitude of LEV rotation was more than 0.5°. The mean thoracic Cobb angle of patients with Lenke 1A idiopathic scoliosis was 51.1° (range 37°-80°), whereas the mean lumbar Cobb angle was 16.4° (range 0°-32°). The mean angle of trunk rotation of the patients was 5.7° (range 1°-16°). In terms of maximum thoracic vertebra rotation, the mean rotation angle of Lenke 1A idiopathic curves was -18.9° (range -(9.8°-44.7°)). The mean maximum lumbar vertebra rotation was 4.5° (range -7.2° to 15.1°). Addition of axial plane analysis to conventional
NASA Astrophysics Data System (ADS)
Vafaeesefat, Abbas
2009-10-01
This paper presents an algorithm for shape optimization of composite pressure vessels head. The shape factor which is defined as the ratio of internal volume to weight of the vessel is used as an objective function. Design constrains consist of the geometrical limitations, winding conditions, and Tsai-Wu failure criterion. The geometry of dome shape is defined by a B-spline rational curve. By altering the weights of control points, depth of dome, and winding angle, the dome shape is changed. The proposed algorithm uses genetic algorithm and finite element analysis to optimize the design parameters. The algorithm is applied on a CNG pressure vessel and the results show that the proposed algorithm can efficiently define the optimal dome shape. This algorithm is general and can be used for general shape optimization.
NASA Astrophysics Data System (ADS)
Chrismianto, Deddy; Zakki, Ahmad Fauzan; Arswendo, Berlian; Kim, Dong Joon
2015-12-01
Optimization analysis and computational fluid dynamics (CFDs) have been applied simultaneously, in which a parametric model plays an important role in finding the optimal solution. However, it is difficult to create a parametric model for a complex shape with irregular curves, such as a submarine hull form. In this study, the cubic Bezier curve and curve-plane intersection method are used to generate a solid model of a parametric submarine hull form taking three input parameters into account: nose radius, tail radius, and length-height hull ratio ( L/ H). Application program interface (API) scripting is also used to write code in the ANSYS design modeler. The results show that the submarine shape can be generated with some variation of the input parameters. An example is given that shows how the proposed method can be applied successfully to a hull resistance optimization case. The parametric design of the middle submarine type was chosen to be modified. First, the original submarine model was analyzed, in advance, using CFD. Then, using the response surface graph, some candidate optimal designs with a minimum hull resistance coefficient were obtained. Further, the optimization method in goal-driven optimization (GDO) was implemented to find the submarine hull form with the minimum hull resistance coefficient ( C t ). The minimum C t was obtained. The calculated difference in C t values between the initial submarine and the optimum submarine is around 0.26%, with the C t of the initial submarine and the optimum submarine being 0.001 508 26 and 0.001 504 29, respectively. The results show that the optimum submarine hull form shows a higher nose radius ( r n ) and higher L/ H than those of the initial submarine shape, while the radius of the tail ( r t ) is smaller than that of the initial shape.
NASA Astrophysics Data System (ADS)
Raftoyiannis, Ioannis G.; Michaltsos, George T.
2016-11-01
This paper deals with the dynamic behavior of curved-in-plane bridges where the effect of the bridge curvature radius, the moving load (vehicle) speed, the truck cant angle, the deck surface conditions and, mainly, the response accuracy depending on the vehicle model used are investigated. Besides the above parameters, the influence of several loading models is studied as well, especially the models of a concentrated load, a damped mass-load, a sequence of two concentrated loads and a real vehicle aswell as a damped vehicle,where its width is taken into account. A 3-DOF model is considered for the analysis of the bridge, while the theoretical formulation is based on a continuum approach, which has been widely used in the literature to analyze such bridges.
Vassilev, V. M.; Djondjorov, P. A.; Hadzhilazova, M. Ts.; Mladenov, I. M.
2011-11-29
The Gardner equation is well-known in the mathematical literature since the late sixties of 20th century. Initially, it appeared in the context of the construction of local conservation laws admitted by the KdV equation. Later on, the Gardner equation was generalized and found to be applicable in various branches of physics (solid-state and plasma physics, fluid dynamics and quantum field theory). In this paper, we examine the travelling wave solutions of the Gardner equation and derive the full set of solutions to the corresponding reduced equation in terms of Weierstrass and Jacobi elliptic functions. Then, we use the travelling wave solutions of the focusing mKdV equation and obtain in explicit analytic form exact solutions of a special type of plane curve flow, known as the mKdV flow.
NASA Technical Reports Server (NTRS)
Cooper, D. B.; Yalabik, N.
1975-01-01
Approximation of noisy data in the plane by straight lines or elliptic or single-branch hyperbolic curve segments arises in pattern recognition, data compaction, and other problems. The efficient search for and approximation of data by such curves were examined. Recursive least-squares linear curve-fitting was used, and ellipses and hyperbolas are parameterized as quadratic functions in x and y. The error minimized by the algorithm is interpreted, and central processing unit (CPU) times for estimating parameters for fitting straight lines and quadratic curves were determined and compared. CPU time for data search was also determined for the case of straight line fitting. Quadratic curve fitting is shown to require about six times as much CPU time as does straight line fitting, and curves relating CPU time and fitting error were determined for straight line fitting. Results are derived on early sequential determination of whether or not the underlying curve is a straight line.
NASA Astrophysics Data System (ADS)
Abenda, Simonetta
2017-09-01
We continue the program started in Abenda and Grinevich (2015) of associating rational degenerations of M-curves to points in GrTNN(k , n) using KP theory for real finite gap solutions. More precisely, we focus on the inverse problem of characterizing the soliton data which produce Krichever divisors compatible with the KP reality condition when Γ is a certain rational degeneration of a hyperelliptic M-curve. Such choice is motivated by the fact that Γ is related to the curves associated to points in GrTP(1 , n) and in GrTP(n - 1 , n) in Abenda and Grinevich (2015). We prove that the reality condition on the Krichever divisor on Γ singles out a special family of KP multi-line solitons (T-hyperelliptic solitons) in GrTP(k , n) , k ∈ [ n - 1 ] , naturally connected to the finite non-periodic Toda hierarchy. We discuss the relations between the algebraic-geometric description of KP T-hyperelliptic solitons and of the open Toda system. Finally, we also explain the effect of the space-time transformation which conjugates soliton data in GrTP(k , n) to soliton data in GrTP(n - k , n) on the Krichever divisor for such KP solitons.
Bézier curves on the shape sphere
NASA Astrophysics Data System (ADS)
Georgiev, Georgi H.
2012-11-01
There are two important models of the simplicial shape space of order (2,3). The first model introduced by D. Kendall is a two-dimensional sphere with radius 1/2. Therefore, this model is called the shape sphere. The second model introduced by F. Bookstein is a one-point extension of the Euclidean plane. Using a natural conformal mapping between these models we investigate curves on the shape sphere which correspond to Bézier curves in the Euclidean plane. We also describe two different types of rational spherical curves and their plane pre-images.
Gadyl'shin, R R
2000-06-30
In this article the two-dimensional Dirichlet boundary-value problem is considered for the Helmholtz operator with boundary conditions on an almost closed curve {gamma}{sub {epsilon}} where {epsilon}<<1 is the distance between the end-points of the curve. A complete asymptotic expression is constructed for a pole of the analytic continuation of the Green's function of this problem as the pole converges to a simple eigenfrequency of the limiting interior problem in the case when the corresponding eigenfunction of the limiting problem has a second-order zero at the centre of contraction of the gap. The influence of symmetry of the gap on the absolute value of the imaginary parts of the poles is investigated.
Curved-space trace, chiral, and Einstein anomalies from path integrals, using flat-space plane waves
NASA Astrophysics Data System (ADS)
Ceresole, A.; Pizzochero, P.; van Nieuwenhuizen, P.
1989-03-01
We show that the gravitational trace and chiral anomalies can be computed from the measure by using the same general flat-space methods as used for nongravitational anomalies. No heat-kernel methods, zeta-function regularization, point-splitting techniques, etc., are needed, although they may be used and then simplify the algebra. In particular, we claim that it is not necessary to insert factors of g1/4 which are often added on grounds of covariance, since one-loop anomalies are local objects, while the trace of the Jacobian of the measure is a purely mathematical object which can be evaluated whether or not one has even heard about general relativity. We also show that the trace operation is cyclic by performing two different computations of the Einstein anomaly: once with the regulator in front of the Jacobian and once in the back. In both cases we obtain total derivatives on a plane-wave basis.
NASA Astrophysics Data System (ADS)
Jörn, Heine; Roland, Damm; Christoph, Gerhard; Stephan, Wieneke; Wolfgang, Viöl
2014-06-01
In this work, surface activation of automotive polymers using atmospheric pressure plasmas was investigated. The aim was to increase the polar fraction of the surface energy of both plane and convex polymer devices with a radius in the range of 30 mm. For this purpose, a fittable low temperature atmospheric pressure plasma source based on capacitively coupled multi-pin electrodes was set up and applied. Each single electrode generates a treatment spot of approximately 2 cm2 with a tunable power density of up to 1.4 W/cm2. The surface energy was evaluated by contact angle measurements. After treatment at a low energy density of 1.01 J/cm2, the polar fraction of the surface energy of the investigated polymers was increased by a factor of 3.3 to 132, depending on the polymer materials. It was shown that by applying the presented fittable plasma source, this effect is independent of the surface radius of the polymer sample.
The computation of all plane/surface intersections for CAD/CAM applications
NASA Technical Reports Server (NTRS)
Hoitsma, D. H., Jr.; Roche, M.
1984-01-01
The problem of the computation and display of all intersections of a given plane with a rational bicubic surface patch for use on an interactive CAD/CAM system is examined. The general problem of calculating all intersections of a plane and a surface consisting of rational bicubic patches is reduced to the case of a single generic patch by applying a rejection algorithm which excludes all patches that do not intersect the plane. For each pertinent patch the algorithm presented computed the intersection curves by locating an initial point on each curve, and computes successive points on the curve using a tolerance step equation. A single cubic equation solver is used to compute the initial curve points lying on the boundary of a surface patch, and the method of resultants as applied to curve theory is used to determine critical points which, in turn, are used to locate initial points that lie on intersection curves which are in the interior of the patch. Examples are given to illustrate the ability of this algorithm to produce all intersection curves.
The computation of all plane/surface intersections for CAD/CAM applications
NASA Technical Reports Server (NTRS)
Hoitsma, D. H., Jr.; Roche, M.
1984-01-01
The problem of the computation and display of all intersections of a given plane with a rational bicubic surface patch for use on an interactive CAD/CAM system is examined. The general problem of calculating all intersections of a plane and a surface consisting of rational bicubic patches is reduced to the case of a single generic patch by applying a rejection algorithm which excludes all patches that do not intersect the plane. For each pertinent patch the algorithm presented computed the intersection curves by locating an initial point on each curve, and computes successive points on the curve using a tolerance step equation. A single cubic equation solver is used to compute the initial curve points lying on the boundary of a surface patch, and the method of resultants as applied to curve theory is used to determine critical points which, in turn, are used to locate initial points that lie on intersection curves which are in the interior of the patch. Examples are given to illustrate the ability of this algorithm to produce all intersection curves.
On noninvertible mappings of the plane: Eruptions.
Billings, Lora; Curry, James H.
1996-06-01
In this paper we are concerned with the dynamics of noninvertible transformations of the plane. Three examples are explored and possibly a new bifurcation, or "eruption," is described. A fundamental role is played by the interactions of fixed points and singular curves. Other critical elements in the phase space include periodic points and an invariant line. The dynamics along the invariant line, in two of the examples, reduces to the one-dimensional Newton's method which is conjugate to a degree two rational map. We also determine, computationally, the characteristic exponents for all of the systems. An unexpected coincidence is that the parameter range where the invariant line becomes neutrally stable, as measured by a zero Lyapunov exponent, coincides with the merging of a periodic point with a point on a singular curve. (c) 1996 American Institute of Physics.
NASA Technical Reports Server (NTRS)
Unz, H.; Roskam, J.
1979-01-01
The theory of acoustic plane wave normally incident on a clamped panel in a rectangular duct is developed. The coupling theory between the elastic vibrations of the panel (plate) and the acoustic wave propagation in infinite space and in the rectangular duct is considered. The partial differential equation which governs the vibration of the panel (plate) is modified by adding to its stiffness (spring) forces and damping forces, and the fundamental resonance frequency and the attenuation factor are discussed. The noise reduction expression based on the theory is found to agree well with the corresponding experimental data of a sample aluminum panel in the mass controlled region, the damping controlled region, and the stiffness controlled region. All the frequency positions of the upward and downward resonance spikes in the sample experimental data are identified theoretically as resulting from four cross interacting major resonance phenomena: the cavity resonance, the acoustic resonance, the plate resonance, and the wooden back panel resonance.
NASA Technical Reports Server (NTRS)
Kearns, James A.
1989-01-01
Phenomena associated with long range propagation of sound over irregular topography motivated this work, which was to analyze the diffraction effects which would occur near the tops of hills and ridges. The diffraction of a high frequency plane wave due to its grazing of a two-dimensional curved surface of finite impedance was also studied. Laboratory scale models were constructed and measurements were made of the field on, above, and behind either of two curved surfaces possessing distinctly different impedances; that is, one was soft while the other was hard. The experimental technique consisted of simultaneously measuring the pressure at a reference point and at a field point due to a transient pulse generated by an electric spark. The pressure waveforms were digitized and processed. The ratio of the discrete Fourier transforms of the two waveforms provided an estimate of the insertion loss between them. The results of the measurements were compared with the predictions of a theory which was derived by Pierce using the method of Matched Asymptotic Expansions (MAE). The predictions relied upon the experimental evaluation of the impedance of each surface at grazing angles of incidence. This evaluation was achieved by a fairly standard technique involving empirical models of various generic types of surfaces. An example was shown of the important role that the structural intricacies of a surface play in the determination of an appropriate model. The comparison between the measurements and predictions indicated that the theory gives an excellent description of the field anywhere near a curved surface. Further, with a simple modification, the theory was also shown to give nearly as good of a description of the field surrounding a curved surface even at distances far behind the surface yet near the line of sight.
ERIC Educational Resources Information Center
Macmillan, C. J. B.
1985-01-01
The recognition of teaching as a special relationship among individuals is currently being overlooked in much contemporary educational research and policymaking. The author examines the philosophy of rationality in teaching and relates it to the educational vision presented in George Orwell's novel, "Nineteen Eighty-Four." (CB)
ERIC Educational Resources Information Center
Macmillan, C. J. B.
1985-01-01
The recognition of teaching as a special relationship among individuals is currently being overlooked in much contemporary educational research and policymaking. The author examines the philosophy of rationality in teaching and relates it to the educational vision presented in George Orwell's novel, "Nineteen Eighty-Four." (CB)
ERIC Educational Resources Information Center
Lam, Chi-Ming
2014-01-01
Nowadays, there is still a widely held view that the Chinese and Western modes of thought are quite distinct from each other. In particular, the Chinese mode of thought derived from Confucianism is considered as comparatively less rational than the Western one. In this article, I first argue that although the analogical mode of argumentation,…
ERIC Educational Resources Information Center
Lam, Chi-Ming
2014-01-01
Nowadays, there is still a widely held view that the Chinese and Western modes of thought are quite distinct from each other. In particular, the Chinese mode of thought derived from Confucianism is considered as comparatively less rational than the Western one. In this article, I first argue that although the analogical mode of argumentation,…
1983-05-01
numbers; may include program from the Standard Distribution for element number(s), project number(s), task Unclassified Scientific and Technical number...Grant TA - Task Block 13. A.trac.t Include a brief (Maximum PE - Program WU- Work Unit 200 words) factual summary of the most Element Accession No...rational constraints for nondeductive argument and inference. Such a notion would also provide a framework for decision theory. The program of finding
Microorganism billiards in closed plane curves.
Krieger, Madison S
2016-12-01
Recent experiments have shown that many species of microorganisms leave a solid surface at a fixed angle determined by steric interactions and near-field hydrodynamics. This angle is completely independent of the incoming angle. For several collisions in a closed body this determines a unique type of billiard system, an aspecular billiard in which the outgoing angle is fixed for all collisions. We analyze such a system using numerical simulation of this billiard for varying tables and outgoing angles, and also utilize the theory of one-dimensional maps and wavefront dynamics. When applicable we cite results from and compare our system to similar billiard systems in the literature. We focus on examples from three broad classes: the ellipse, the Bunimovich billiards, and the Sinai billiards. The effect of a noisy outgoing angle is also discussed.
NASA Technical Reports Server (NTRS)
Schiess, James R.; Kerr, Patricia A.; Smith, Olivia C.
1988-01-01
Smooth curves drawn among plotted data easily. Rational-Spline Approximation with Automatic Tension Adjustment algorithm leads to flexible, smooth representation of experimental data. "Tension" denotes mathematical analog of mechanical tension in spline or other mechanical curve-fitting tool, and "spline" as denotes mathematical generalization of tool. Program differs from usual spline under tension, allows user to specify different values of tension between adjacent pairs of knots rather than constant tension over entire range of data. Subroutines use automatic adjustment scheme that varies tension parameter for each interval until maximum deviation of spline from line joining knots less than or equal to amount specified by user. Procedure frees user from drudgery of adjusting individual tension parameters while still giving control over local behavior of spline.
Rationalization: A Bibliography.
ERIC Educational Resources Information Center
Pedrini, D. T.; Pedrini, Bonnie C.
Rationalization was studied by Sigmund Freud and was specifically labeled by Ernest Jones. Rationalization ought to be differentiated from rational, rationality, logical analysis, etc. On the one hand, rationalization is considered a defense mechanism, on the other hand, rationality is not. Haan has done much work with self-report inventories and…
Birational maps that send biquadratic curves to biquadratic curves
NASA Astrophysics Data System (ADS)
Roberts, John A. G.; Jogia, Danesh
2015-02-01
Recently, many papers have begun to consider so-called non-Quispel-Roberts-Thompson (QRT) birational maps of the plane. Compared to the QRT family of maps which preserve each biquadratic curve in a fibration of the plane, non-QRT maps send a biquadratic curve to another biquadratic curve belonging to the same fibration or to a biquadratic curve from a different fibration of the plane. In this communication, we give the general form of a birational map derived from a difference equation that sends a biquadratic curve to another. The necessary and sufficient condition for such a map to exist is that the discriminants of the two biquadratic curves are the same (and hence so are the j-invariants). The result allows existing examples in the literature to be better understood and allows some statements to be made concerning their generality.
Wilkinson, Dominic
2017-01-01
Decisions about allocation of limited healthcare resources are frequently controversial. These decisions are usually based on careful analysis of medical, scientific and health economic evidence. Yet, decisions are also necessarily based on value judgements. There may be differing views among health professionals about how to allocate resources or how to evaluate existing evidence. In specific cases, professionals may have strong personal views (contrary to professional or societal norms) that treatment should or should not be provided. Could these disagreements rise to the level of a conscientious objection? If so, should conscientious objections to existing allocation decisions be accommodated? In the first part of this paper, I assess whether resource allocation could be a matter of conscience. I analyse conceptual and normative models of conscientious objection and argue that rationing could be a matter for conscience. I distinguish between negative and positive forms: conscientious non-treatment and conscientious treatment. In the second part of the paper, I identify distinctive challenges for conscientious objections to resource allocation. Such objections are almost always inappropriate. PMID:27733437
Monotone data visualization using rational trigonometric spline interpolation.
Ibraheem, Farheen; Hussain, Maria; Hussain, Malik Zawwar
2014-01-01
Rational cubic and bicubic trigonometric schemes are developed to conserve monotonicity of curve and surface data, respectively. The rational cubic function has four parameters in each subinterval, while the rational bicubic partially blended function has eight parameters in each rectangular patch. The monotonicity of curve and surface data is retained by developing constraints on some of these parameters in description of rational cubic and bicubic trigonometric functions. The remaining parameters are kept free to modify the shape of curve and surface if required. The developed algorithm is verified mathematically and demonstrated graphically.
Monotone Data Visualization Using Rational Trigonometric Spline Interpolation
Ibraheem, Farheen; Hussain, Maria
2014-01-01
Rational cubic and bicubic trigonometric schemes are developed to conserve monotonicity of curve and surface data, respectively. The rational cubic function has four parameters in each subinterval, while the rational bicubic partially blended function has eight parameters in each rectangular patch. The monotonicity of curve and surface data is retained by developing constraints on some of these parameters in description of rational cubic and bicubic trigonometric functions. The remaining parameters are kept free to modify the shape of curve and surface if required. The developed algorithm is verified mathematically and demonstrated graphically. PMID:24955413
ERIC Educational Resources Information Center
Lawes, Jonathan F.
2013-01-01
Graphing polar curves typically involves a combination of three traditional techniques, all of which can be time-consuming and tedious. However, an alternative method--graphing the polar function on a rectangular plane--simplifies graphing, increases student understanding of the polar coordinate system, and reinforces graphing techniques learned…
Fourie-Mukai partners of singular genus one curves
NASA Astrophysics Data System (ADS)
López Martín, Ana Cristina
2014-09-01
The objective of the paper is to prove that, as it happens for smooth elliptic curves, any Fourie-Mukai partner of a projective reduced Gorenstein curve of genus one and trivial dualizing sheaf, is isomorphic to itself. either to a Kodaira curve (always with locally planar singularities), that is, a smooth elliptic curve; a rational curve with one node (following Kodaira's notation, that is a curve of type I1); a rational curve with one cusp (a curve of type I2); a cycle of N rational smooth curves (a curve of type IN) with N≥2; two rational smooth curves forming a tacnode curve (a curve of type II); or three concurrent rational smooth curves in the plane (a curve of type IV); or to a curve consisting of N≥4 rational smooth curves meeting at a point x where the tangents to the branches are linearly dependent, but any (N-1) of them are independent. Note that, by results of Kodaira and Miranda, the curves in (1) are exactly all the possible reduced fibers appearing in a smooth elliptic surface or in a smooth elliptic threefold. This explains why they are called Kodaira curves.The theorem was just known for smooth elliptic curves. In this case, it was proved by Hille and Van den Bergh in [2]. For the integral singular curves in the above list, that is, for X a rational curve with one node or a cusp, Burban and Kreußler study in [3] the derived category Dcb(X) and its group Aut(Dcb(X) of autoequivalences, but they do not tackle the question of Fourie-Mukai partners. Thus our contribution is to pass from the classical case of a smooth elliptic curve to the singular case generalizing the result to all singular curves of Catanese's list.In 1998, Bridgeland computes all Fourie-Mukai partners of a smooth elliptic surface. He proves in [4] that the partners of relatively minimal smooth elliptic surfaces are certain relative compactified Jacobians. Some recent works [5,6] are concerned about higher dimensional elliptic fibrations. But, for the moment there is not a
NASA Technical Reports Server (NTRS)
Schiess, J. R.
1994-01-01
Scientific data often contains random errors that make plotting and curve-fitting difficult. The Rational-Spline Approximation with Automatic Tension Adjustment algorithm lead to a flexible, smooth representation of experimental data. The user sets the conditions for each consecutive pair of knots:(knots are user-defined divisions in the data set) to apply no tension; to apply fixed tension; or to determine tension with a tension adjustment algorithm. The user also selects the number of knots, the knot abscissas, and the allowed maximum deviations from line segments. The selection of these quantities depends on the actual data and on the requirements of a particular application. This program differs from the usual spline under tension in that it allows the user to specify different tension values between each adjacent pair of knots rather than a constant tension over the entire data range. The subroutines use an automatic adjustment scheme that varies the tension parameter for each interval until the maximum deviation of the spline from the line joining the knots is less than or equal to a user-specified amount. This procedure frees the user from the drudgery of adjusting individual tension parameters while still giving control over the local behavior of the spline The Rational Spline program was written completely in FORTRAN for implementation on a CYBER 850 operating under NOS. It has a central memory requirement of approximately 1500 words. The program was released in 1988.
NASA Technical Reports Server (NTRS)
Schiess, J. R.
1994-01-01
Scientific data often contains random errors that make plotting and curve-fitting difficult. The Rational-Spline Approximation with Automatic Tension Adjustment algorithm lead to a flexible, smooth representation of experimental data. The user sets the conditions for each consecutive pair of knots:(knots are user-defined divisions in the data set) to apply no tension; to apply fixed tension; or to determine tension with a tension adjustment algorithm. The user also selects the number of knots, the knot abscissas, and the allowed maximum deviations from line segments. The selection of these quantities depends on the actual data and on the requirements of a particular application. This program differs from the usual spline under tension in that it allows the user to specify different tension values between each adjacent pair of knots rather than a constant tension over the entire data range. The subroutines use an automatic adjustment scheme that varies the tension parameter for each interval until the maximum deviation of the spline from the line joining the knots is less than or equal to a user-specified amount. This procedure frees the user from the drudgery of adjusting individual tension parameters while still giving control over the local behavior of the spline The Rational Spline program was written completely in FORTRAN for implementation on a CYBER 850 operating under NOS. It has a central memory requirement of approximately 1500 words. The program was released in 1988.
Duality concept in curve and surface modelling
NASA Astrophysics Data System (ADS)
Kmetova, Maria; Kmet, Tibor
2012-09-01
The paper deals with projective construction of envelope conic section, line conic and its corresponding point conic and generally, with dual Bézier curve and its corresponding point curve. Also, the role of dual Bézier curves in surface modelling is studied. Duality concept is useful in both; special plane curve modelling and developable surface modelling.
Precise measurement of planeness.
Schulz, G; Schwider, J
1967-06-01
Interference methods are reviewed-particularly those developed at the German Academy of Sciences in Berlin-with which the deviations of an optically flat surface from the ideal plane can be measured with a high degree of exactness. One aid to achieve this is the relative methods which measure the differences in planeness between two surfaces. These are then used in the absolute methods which determine the absolute planeness of a surface. This absolute determination can be effected in connection with a liquid surface, or (as done by the authors) only by suitable evaluation of relative measurements between unknown plates in various positional combinations. Experimentally, one uses two- or multiple-beam interference fringes of equal thickness(1) or of equal inclination. The fringes are observed visually, scanned, or photographed, and in part several wavelengths or curves of equal density (Aquidensiten) are employed. The survey also brings the following new methods: a relative method, where, with the aid of fringes of superposition, the fringe separation is subdivided equidistantly thus achieving an increase of measuring precision, and an absolute method which determines the deviations of a surface from ideal planeness along arbitrary central sections, without a liquid surface, from four relative interference photographs.
Automated reasoning about cubic curves.
Padmanabhan, R.; McCune, W.; Mathematics and Computer Science; Univ. of Manitoba
1995-01-01
It is well known that the n-ary morphisms defined on projective algebraic curves satisfy some strong local-to-global equational rules of derivation not satisfied in general by universal algebras. For example, every rationally defined group law on a cubic curve must be commutative. Here we extract from the geometry of curves a first order property (gL) satisfied by all morphisms defined on these curves such that the equational consequences known for projective curves can be derived automatically from a set of six rules (stated within the first-order logic with equality). First, the rule (gL) is implemented in the theorem-proving program Otter. Then we use Otter to automatically prove some incidence theorems on projective curves without any further reference to the underlying geometry or topology of the curves.
NASA Technical Reports Server (NTRS)
Munk, Max M
1923-01-01
This report deals with the calculation of the equilibrium, statistical stability, and damping of the tail plane. The author has simplified the present theory of longitudinal stability for the particular purpose of obtaining one definite coefficient characteristics of the effect of the tail plane. This coefficient is obtained by substituting certain aerodynamic characteristics and some dimensions of the airplane in a comparatively simple mathematical expression. Care has been taken to confine all aerodynamical information necessary for the calculation of the coefficient to the well-known curves representing the qualities of the wing section. This is done by making use of the present results of modern aerodynamics. All formulas and relations necessary for the calculation are contained in the paper. They give in some cases only an approximation of the real values. An example of calculation is added in order to illustrate the application of the method. The coefficient indicates not only whether the effect of the tail plane is great enough, but also whether it is not too great. It appears that the designer has to avoid a certain critical length of the fuselage, which inevitably gives rise to periodical oscillations of the airplane. The discussion also shows the way and in what direction to carry out experimental work.
NASA Astrophysics Data System (ADS)
Kassotakis, Pavlos; Nieszporski, Maciej
2017-05-01
We present a natural extension of the notion of nondegenerate rational maps (quadrirational maps) to arbitrary dimensions. We refer to these maps as 2 n -rational maps. In this note we construct a rich family of 2 n -rational maps. These maps by construction are involutions and highly symmetric in the sense that the maps and their companion maps have the same functional form.
Convexity preserving C2 rational quadratic trigonometric spline
NASA Astrophysics Data System (ADS)
Dube, Mridula; Tiwari, Preeti
2012-09-01
A C2 rational quadratic trigonometric spline interpolation has been studied using two kind of rational quadratic trigonometric splines. It is shown that under some natural conditions the solution of the problem exits and is unique. The necessary and sufficient condition that constrain the interpolation curves to be convex in the interpolating interval or subinterval are derived.
NASA Astrophysics Data System (ADS)
Frønsdal, Christian; Kontsevich, Maxim
2007-02-01
Deformation quantization on varieties with singularities offers perspectives that are not found on manifolds. The Harrison component of Hochschild cohomology, vanishing on smooth manifolds, reflects information about singularities. The Harrison 2-cochains are symmetric and are interpreted in terms of abelian *-products. This paper begins a study of abelian quantization on plane curves over mathbb{C}, being algebraic varieties of the form {mathbb{C}}^2/R, where R is a polynomial in two variables; that is, abelian deformations of the coordinate algebra mathbb{C}[x,y]/(R). To understand the connection between the singularities of a variety and cohomology we determine the algebraic Hochschild (co)homology and its Barr Gerstenhaber Schack decomposition. Homology is the same for all plane curves mathbb{C}[x,y]/R, but the cohomology depends on the local algebra of the singularity of R at the origin. The Appendix, by Maxim Kontsevich, explains in modern mathematical language a way to calculate Hochschild and Harrison cohomology groups for algebras of functions on singular planar curves etc. based on Koszul resolutions.
Abnormality, rationality, and sanity.
Hertwig, Ralph; Volz, Kirsten G
2013-11-01
A growing body of studies suggests that neurological and mental abnormalities foster conformity to norms of rationality that are widely endorsed in economics and psychology, whereas normality stands in the way of rationality thus defined. Here, we outline the main findings of these studies, discuss their implications for experimental design, and consider how 'sane' some benchmarks of rationality really are. Copyright © 2013 Elsevier Ltd. All rights reserved.
Causal inheritence in plane wave quotients
Hubeny, Veronika E.; Rangamani, Mukund; Ross, Simon F.
2003-11-24
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.
Standby Gasoline Rationing Plan
1980-06-01
The final rules adopted by the President for a Standby Gasoline Rationing Plan are presented. The plan provides that eligibility for ration allotments will be determined primarily on the basis of motor vehicle registrations, taking into account historical differences in the use of gasoline among states. The regulations also provide authority for supplemental allotments to firms so that their allotment will equal a specified percentage of gasoline use during a base period. Priority classifications, i.e., agriculture, defense, etc., are established to assure adequate gasoline supplies for designated essential services. Ration rights must be provided by end-users to their suppliers for each gallon sold. DOE will regulate the distribution of gasoline at the wholesale level according to the transfer by suppliers of redeemed ration rights and the gasoline allocation regulations. Ration rights are transferable. A ration banking system is created to facilitate transfers of ration rights. Each state will be provided with a reserve of ration rights to provide for hardship needs and to alleviate inequities. (DC)
Enculturated Chimpanzees Imitate Rationally
ERIC Educational Resources Information Center
Buttelmann, David; Carpenter, Malinda; Call, Josep; Tomasello, Michael
2007-01-01
Human infants imitate others' actions "rationally": they copy a demonstrator's action when that action is freely chosen, but less when it is forced by some constraint (Gergely, Bekkering & Kiraly, 2002). We investigated whether enculturated chimpanzees (Pan troglodytes) also imitate rationally. Using Gergely and colleagues' (2002) basic procedure,…
ERIC Educational Resources Information Center
Rousseau, Ronald
1994-01-01
Discussion of informetric distributions shows that generalized Leimkuhler functions give proper fits to a large variety of Bradford curves, including those exhibiting a Groos droop or a rising tail. The Kolmogorov-Smirnov test is used to test goodness of fit, and least-square fits are compared with Egghe's method. (Contains 53 references.) (LRW)
Respect for rational autonomy.
Walker, Rebecca L
2009-12-01
The standard notion of autonomy in medical ethics does not require that autonomous choices not be irrational. The paper gives three examples of seemingly irrational patient choices and discusses how a rational autonomy analysis differs from the standard view. It then considers whether a switch to the rational autonomy view would lead to overriding more patient decisions but concludes that this should not be the case. Rather, a determination of whether individual patient decisions are autonomous is much less relevant than usually considered in determining whether health care providers must abide by these decisions. Furthermore, respect for rational autonomy entails strong positive requirements of respect for the autonomy of the person as a rational decision maker. The rationality view of autonomy is conceptually stronger than the standard view, allows for a more nuanced understanding of the practical moral calculus involved in respecting patient autonomy, and promotes positive respect for patient autonomy.
Rational Solutions for the Fokas System
NASA Astrophysics Data System (ADS)
Rao, Ji-Guang; Wang, Li-Hong; Zhang, Yu; He, Jing-Song
2015-12-01
Fokas system is the simplest (2+1)-dimensional extension of the nonlinear Schrödinger equation (Eq. (2), Inverse Problems 10 (1994) L19-L22). By using the bilinear transformation method, general rational solutions for the Fokas system are given explicitly in terms of two order-N determinants τn (n = 0, 1) whose elements m(n)i,j (n = 0, 1; 1 ≤ i, j ≤ N) are involved with order-ni and order-nj derivatives. When N = 1, three kinds of rational solution, i.e., fundamental lump and fundamental rogue wave (RW) with n1 = 1, and higher-order rational solution with n1 ≥ 2, are illustrated by explicit formulas from τn (n = 0, 1) and pictures. The fundamental RW is a line RW possessing a line profile on (x, y)-plane, which arises from a constant background with at t ≪ 0 and then disappears into the constant background gradually at t ≫ 0. The fundamental lump is a traveling wave, which can preserve its profile during the propagation on (x, y)-plane. When N ≥ 2 and n1 = n2 = · · · = nN = 1, several specific multi-rational solutions are given graphically. Supported by the National Natural Science Foundation of China under Grant No. 11271210, the K.C. Wong Magna Fund in Ningbo University
Surfaces with Rational Chord Length Parameterization
NASA Astrophysics Data System (ADS)
Bastl, Bohumír; Jüttler, Bert; Lávička, Miroslav; Šír, Zbyněk
We consider a rational triangular Bézier surface of degree n and study conditions under which it is rationally parameterized by chord lengths (RCL surface) with respect to the reference circle. The distinguishing property of these surfaces is that the ratios of the three distances of a point to the three vertices of an arbitrary triangle inscribed to the reference circle and the ratios of the distances of the parameter point to the three vertices of the corresponding domain triangle are identical. This RCL property, which extends an observation from [10,13] about rational curves parameterized by chord lengths, was firstly observed in the surface case for patches on spheres in [2]. In the present paper, we analyze the entire family of RCL surfaces, provide their general parameterization and thoroughly investigate their properties.
[Concepts of rational taxonomy].
Pavlinov, I Ia
2011-01-01
The problems are discussed related to development of concepts of rational taxonomy and rational classifications (taxonomic systems) in biology. Rational taxonomy is based on the assumption that the key characteristic of rationality is deductive inference of certain partial judgments about reality under study from other judgments taken as more general and a priory true. Respectively, two forms of rationality are discriminated--ontological and epistemological ones. The former implies inference of classifications properties from general (essential) properties of the reality being investigated. The latter implies inference of the partial rules of judgments about classifications from more general (formal) rules. The following principal concepts of ontologically rational biological taxonomy are considered: "crystallographic" approach, inference of the orderliness of organismal diversity from general laws of Nature, inference of the above orderliness from the orderliness of ontogenetic development programs, based on the concept of natural kind and Cassirer's series theory, based on the systemic concept, based on the idea of periodic systems. Various concepts of ontologically rational taxonomy can be generalized by an idea of the causal taxonomy, according to which any biologically sound classification is founded on a contentwise model of biological diversity that includes explicit indication of general causes responsible for that diversity. It is asserted that each category of general causation and respective background model may serve as a basis for a particular ontologically rational taxonomy as a distinctive research program. Concepts of epistemologically rational taxonomy and classifications (taxonomic systems) can be interpreted in terms of application of certain epistemological criteria of substantiation of scientific status of taxonomy in general and of taxonomic systems in particular. These concepts include: consideration of taxonomy consistency from the
Monotonicity preserving splines using rational cubic Timmer interpolation
NASA Astrophysics Data System (ADS)
Zakaria, Wan Zafira Ezza Wan; Alimin, Nur Safiyah; Ali, Jamaludin Md
2017-08-01
In scientific application and Computer Aided Design (CAD), users usually need to generate a spline passing through a given set of data, which preserves certain shape properties of the data such as positivity, monotonicity or convexity. The required curve has to be a smooth shape-preserving interpolant. In this paper a rational cubic spline in Timmer representation is developed to generate interpolant that preserves monotonicity with visually pleasing curve. To control the shape of the interpolant three parameters are introduced. The shape parameters in the description of the rational cubic interpolant are subjected to monotonicity constrained. The necessary and sufficient conditions of the rational cubic interpolant are derived and visually the proposed rational cubic Timmer interpolant gives very pleasing results.
[Rational use of antibiotics].
Walger, P
2016-06-01
International and national campaigns draw attention worldwide to the rational use of the available antibiotics. This has been stimulated by the high prevalence rates of drug-resistant pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE), a threatening spread of development of resistance in Gram-negative rod-shaped bacteria and the selection of Clostridium difficile with a simultaneous clear reduction in the development of new antibiotics. The implementation of antibiotic stewardship programs aims to maintain their effectiveness by a rational use of the available antibiotics. The essential target of therapy with antibiotics is successful treatment of individual patients with bacterial infections. The optimal clinical treatment results can only be achieved when the toxicity, selection of pathogens and development of resistance are minimized. This article presents the principles of a rational antibiotic therapy.
NASA Astrophysics Data System (ADS)
Bas, E.; Kahraman, C.
2009-02-01
In this paper, we study the fuzzification of Weingartner's pure capital rationing model and its analysis. We develop a primal-dual pair based on t-norm/t-conorm relation for the constraints and objective function for a fully fuzzified pure capital rationing problem except project selection variables. We define the [alpha]-interval under which the weak duality is proved. We perform sensitivity analysis for a change in a budget level or in a cash flow level of a non-basic as well as a basic variable. We analyze the problem based on duality and complementary slackness results. We illustrate the proposed model by computational analysis, and interpret the results.
Spacefilling Curves and Routing Problems in the Plane,
1983-02-11
requires only O(N) meory , and May be impleMented to execute in O(N log N) operations at Most, or O(N) operations on the average. If the points lie in...produces a tour whose length, L, satisfies L 4 NP(I/N) = N - We also consider ihow long the heuristic tour may be In relation to the optimal tour. Theorem...is lengthy and will be given in Section 8. We note that the dominant term In the exact bound for L/L* (Eq. (6.5)) increases slowly in N but rapidly in
ERIC Educational Resources Information Center
Shaughnessy, Michael F.
This paper reviews the main research in the area of human reasoning and rational thinking to determine if man is either an "innately inefficient thinking machine" or if man's irrationality is "rooted in basic human nature," as Ellis (1976) suggests. The paper focuses on the work of two English theorists, Wason and…
Diagnosis, Dogmatism, and Rationality.
ERIC Educational Resources Information Center
Rabinowitz, Jonathan; Efron, Noah J.
1997-01-01
Presents findings suggesting that misdiagnoses frequently stem from flaws in human information processing, particularly in collecting and using information. Claims that improved diagnostic tools will not remedy the problem. Drawing on the work of Karl Popper and Robin Collingwood, proposes operational principles to ensure a rational diagnostic…
Rationality and social behavior.
Tullberg, Jan
2003-10-21
This article penetrates the relationship between social behavior and rationality. A critical analysis is made of efforts to classify some behaviors as altruistic, as they simultaneously meet criteria of rationality by not truly being self-destructive. Newcomb's paradox is one attempt to create a hybrid behavior that is both irrational and still meets some criterion of rationality. Such dubious rationality is often seen as a source of altruistic behavior. Group selection is a controversial topic. Sober and Wilson (Unto Others--The Evolution and Psychology of Unselfish Behavior, Harvard University Press, Cambridge, MA, 1998) suggest that a very wide concept of group selection might be used to explain altruism. This concept also includes kin selection and reciprocity, which blurs its focus. The latter mechanisms hardly need further arguments to prove their existence. This article suggests that it is group selection in a strict sense that should be investigated to limit semantic neologism and confusion. In evaluation, the effort to muster a mechanism for altruism out of group selection has not been successful. However, this is not the end to group selection, but rather a good reason to investigate more promising possibilities. There is little reason to burden group selection with the instability of altruism caused by altruistic members of a group having lower fitness than egoistic members. Group selection is much more likely to develop in combination with group egoism. A common project is supported by incitement against free riding, where conformist members joined in solidarity achieve a higher fitness than members pursuing more individualistic options. Group egoism is in no conflict with rationality, and the effects of group selection will be supported rather than threatened by individual selection. Empirical evidence indicates a high level of traits such as conformism and out-group antagonism in line with group egoism. These traits are also likely candidates for
A rational trigonometric spline to visualize positive data
NASA Astrophysics Data System (ADS)
Bashir, Uzma; Ali, Jamaludin Md.
2014-07-01
In this paper, we construct a cubic trigonometric Bézier curve with two shape parameters on the basis of cubic trigonometric Bernstein-like blending functions. The proposed curve has all geometric properties of the ordinary cubic Bézier curve. Later, based on these trigonometric blending functions a C1 rational trigonometric spline with four shape parameters to preserve positivity of positive data is generated. Simple data dependent constraints are developed for these shape parameters to get a graphically smooth and visually pleasant curve.
Analysis of velocity planning interpolation algorithm based on NURBS curve
NASA Astrophysics Data System (ADS)
Zhang, Wanjun; Gao, Shanping; Cheng, Xiyan; Zhang, Feng
2017-04-01
To reduce interpolation time and Max interpolation error in NURBS (Non-Uniform Rational B-Spline) inter-polation caused by planning Velocity. This paper proposed a velocity planning interpolation algorithm based on NURBS curve. Firstly, the second-order Taylor expansion is applied on the numerator in NURBS curve representation with parameter curve. Then, velocity planning interpolation algorithm can meet with NURBS curve interpolation. Finally, simulation results show that the proposed NURBS curve interpolator meet the high-speed and high-accuracy interpolation requirements of CNC systems. The interpolation of NURBS curve should be finished.
Hydrodynamic Properties of Planing Surfaces and Flying Boats
NASA Technical Reports Server (NTRS)
Sokolov, N. A.
1950-01-01
The study of the hydrodynamic properties of planing bottom of flying boats and seaplane floats is at the present time based exclusively on the curves of towing tests conducted in tanks. In order to provide a rational basis for the test procedure in tanks and practical design data, a theoretical study must be made of the flow at the step and relations derived that show not only qualitatively but quantitatively the inter-relations of the various factors involved. The general solution of the problem of the development of hydrodynamic forces during the motion of the seaplane float or flying boat is very difficult for it is necessary to give a three-dimensional solution, which does not always permit reducing the analysis to the form of workable computation formulas. On the other had, the problem is complicated by the fact that the object of the analysis is concerned with two fluid mediums, namely, air and water, which have a surface of density discontinuity between them. The theoretical and experimental investigations on the hydrodynamics of a ship cannot be completely carried over to the design of floats and flying-boat hulls, because of the difference in the shape of the contour lines of the bodies, and, because of the entirely different flow conditions from the hydrodynamic viewpoint.
Ornstein, R.L.
1994-05-01
Protein engineering is first a means of elucidating structure-function relations in an enzyme, and second, a means of changing a protein to make it serve a different, but generally related, purpose. In principle, one may change the functional characteristics of an enzyme by altering its substrate specificity, kinetics, optimum range of activity, and chemical mechanism. Obviously one cannot make all possible combinations of amino acid changes for even the smallest enzyme, so the essential question is which changes to make. The intent of rational protein/enzyme redesign is to alter a protein/enzyme in a timely and premeditated fashion. This article provides an outline of the process of rational enzyme redesign.
ERIC Educational Resources Information Center
Yates, Robert C.
This volume, a reprinting of a classic first published in 1952, presents detailed discussions of 26 curves or families of curves, and 17 analytic systems of curves. For each curve the author provides a historical note, a sketch or sketches, a description of the curve, a discussion of pertinent facts, and a bibliography. Depending upon the curve,…
1981-11-01
Press. Debreu , Gerard , [19591, The Theory of Value, John Wiley & Sons, New York. "Continuity Properties of Paretian Utility," L1964], International...infinite cardinality, as found in the traditional treatment of Paretian utility as set forth by Debreu [7] II. Rational Choice Functions Typically, one...setting for the problem of consumer choice in economic theory ( Debreu , [1959], Ch.IV). This capability is obtained by means of the concept of a recursive
1985-03-01
8217.--..- .--. ..... .. ......-..- . .-- .. : .. ., . . . - .. .. ....-. . . . Theorem 2 will not hold under minimal deal rationality. Imagine that a perverse opponent chooses his offer group as follows: 1. If you include in your...agents’ behavior (citing the similarity with [25]): (A3). If a game has a single Pareto equilibrium, the players will choose the strategy which...prominent solution. [A Taxonomy of 2 x 2 Games] In short, game theory has been willing to take for granted certain types of behavior without
Exploring rationality in schizophrenia
Mortensen, Erik Lykke; Owen, Gareth; Nordgaard, Julie; Jansson, Lennart; Sæbye, Ditte; Flensborg-Madsen, Trine; Parnas, Josef
2015-01-01
Background Empirical studies of rationality (syllogisms) in patients with schizophrenia have obtained different results. One study found that patients reason more logically if the syllogism is presented through an unusual content. Aims To explore syllogism-based rationality in schizophrenia. Method Thirty-eight first-admitted patients with schizophrenia and 38 healthy controls solved 29 syllogisms that varied in presentation content (ordinary v. unusual) and validity (valid v. invalid). Statistical tests were made of unadjusted and adjusted group differences in models adjusting for intelligence and neuropsychological test performance. Results Controls outperformed patients on all syllogism types, but the difference between the two groups was only significant for valid syllogisms presented with unusual content. However, when adjusting for intelligence and neuropsychological test performance, all group differences became non-significant. Conclusions When taking intelligence and neuropsychological performance into account, patients with schizophrenia and controls perform similarly on syllogism tests of rationality. Declaration of interest None. Copyright and usage © The Royal College of Psychiatrists 2015. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence. PMID:27703730
Rationality in medicine: an explication.
Gert, B; Clouser, K D
1986-05-01
Various meanings of "rational" implicitly and explicitly suggested in this issue's articles are abstracted and stated. Two accounts of rationality are shown to be able to explain most uses of "rational": the "cool moment" account and a more objective account. The former is examined and modified, but still found inadequate. The objective account of rational is developed, taking "irrational" as the basic concept. "Irrational" is given content in terms of a list, and "rational" is subsequently defined as "not irrational". Reasons and motives are defined and distinguished. The advantages of the objective account are explored and some challenges to it are answered.
Experiments with Planing Surfaces
NASA Technical Reports Server (NTRS)
Sottorf, W
1934-01-01
A previous report discusses the experimental program of a systematic exploration of all questions connected with the planing problem as well as the first fundamental results of the investigation of a flat planing surface. The present report is limited to the conversion of the model test data to full scale.
Computation of turbulent boundary layers on curved surfaces, 1 June 1975 - 31 January 1976
NASA Technical Reports Server (NTRS)
Wilcox, D. C.; Chambers, T. L.
1976-01-01
An accurate method was developed for predicting effects of streamline curvature and coordinate system rotation on turbulent boundary layers. A new two-equation model of turbulence was developed which serves as the basis of the study. In developing the new model, physical reasoning is combined with singular perturbation methods to develop a rational, physically-based set of equations which are, on the one hand, as accurate as mixing-length theory for equilibrium boundary layers and, on the other hand, suitable for computing effects of curvature and rotation. The equations are solved numerically for several boundary layer flows over plane and curved surfaces. For incompressible boundary layers, results of the computations are generally within 10% of corresponding experimental data. Somewhat larger discrepancies are noted for compressible applications.
Manvi, Supriya; Miglani, Shaveta; Rajeswari, C L; Srivatsa, G; Arora, Sarvesh
2012-01-01
Proper occlusal plane is an essential consideration when multiple long span posterior restorations are designed. The determination of the occlusal plane can have a profound effect on the short and long term success of a restorative case. Purpose of Study. (1) To determine the appropriate occlusal curve for individual patients. (2) To compare the deviation of the clinical occlusal curve with the ideal ones. Materials and Methods. A total of 20 subjects were examined and study models were made of their maxillary and mandibular dentition. Inter-occlusal records were made and the casts were articulated in semiadjustable articulator. An ideal occlusal plane was created. The distance of the farthest cusp tip from the Broadrick curve was measured along the long axis of the tooth for each individual. Paired t-tests were used to compare the findings between subjects and controls. Results. A statistically significant difference P < 0.05 was found in the deviation from the Broadrick curve between patients who have lost posterior teeth and the control group who had a full dentition with no missing teeth. Conclusion. Proper utilization of the broadrick flag on a semi-adjustable articulator will allow for a correct determination of the occlusal plane.
Rational solutions to the KPI equation and multi rogue waves
NASA Astrophysics Data System (ADS)
Gaillard, Pierre
2016-04-01
We construct here rational solutions to the Kadomtsev-Petviashvili equation (KPI) as a quotient of two polynomials in x, y and t depending on several real parameters. This method provides an infinite hierarchy of rational solutions written in terms of polynomials of degrees 2 N(N + 1) in x, y and t depending on 2 N - 2 real parameters for each positive integer N. We give explicit expressions of the solutions in the simplest cases N = 1 and N = 2 and we study the patterns of their modulus in the (x , y) plane for different values of time t and parameters.
Mandal, Soma; Moudgil, Mee'nal; Mandal, Sanat K
2009-12-25
In this article, current knowledge of drug design is reviewed and an approach of rational drug design is presented. The process of drug development is challenging, expensive, and time consuming, although this process has been accelerated due to the development of computational tools and methodologies. The current target based drug design approach is incomplete because most of the drugs developed by structure guided approaches have been shown to have serious toxic side effects. Otherwise these drugs would have been an ideal choice for the treatment of diseases. Hence, rational drug design would require a multidisciplinary approach. In this regard, incorporation of gene expression technology and bioinformatics tools would be indispensable in the structure based drug design. Global gene expression data and analysis of such data using bioinformatics tools will have numerous benefits such as efficiency, cost effectiveness, time saving, and will provide strategies for combination therapy in addition to overcoming toxic side effects. As a result of incorporation of gene expression data, partial benefit of the structure based drug design is slowly emerging and rapidly changing the approach of the drug development process. To achieve the full benefit of developing a successful drug, multidisciplinary approaches (approaches such as computational chemistry and gene expression analysis, as discussed in this article) would be necessary. In the future, there is adequate room for the development of more sophisticated methodologies.
Fourier plane imaging microscopy
Dominguez, Daniel Peralta, Luis Grave de; Alharbi, Nouf; Alhusain, Mdhaoui; Bernussi, Ayrton A.
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.
Crack growth measured on flat and curved surfaces at cryogenic temperatures
NASA Technical Reports Server (NTRS)
Orange, T. W.; Sullivan, T. L.
1967-01-01
Multiple element continuity gage measures plane stress crack growth plus surface crack growth under plane strain conditions. The gage measures flat and curved surfaces and operates at cryogenic temperatures.
Comparison of Two Algebraic Methods for Curve/curve Intersection
NASA Technical Reports Server (NTRS)
Demontaudouin, Y.; Tiller, W.
1985-01-01
Most geometric modeling systems use either polynomial or rational functions to represent geometry. In such systems most computational problems can be formulated as systems of polynomials in one or more variables. Classical elimination theory can be used to solve such systems. Here Cayley's method of elimination is summarized and it is shown how it can best be used to solve the curve/curve intersection problem. Cayley's method was found to be a more straightforward approach. Furthermore, it is computationally simpler, since the elements of the Cayley matrix are one variable instead of two variable polynomials. Researchers implemented and tested both methods and found Cayley's to be more efficient. Six pairs of curves, representing mixtures of lines, circles, and cubic arcs were used. Several examples had multiple intersection points. For all six cases Cayley's required less CPU time than the other method. The average time ratio of method 1 to method 2 was 3.13:1, the least difference was 2.33:1, and the most dramatic was 6.25:1. Both of the above methods can be extended to solve the surface/surface intersection problem.
Bound Rationality and Organizational Learning.
1989-09-23
8217 . 90 0 8 0.. O 4 BOUNDED RATIONALITY AND ORGANIZATIONAL LEARNING Technical Report AlP - 107 Herbert A. Simon Department of Psychology Carnegie Mellon...ACCESSION No N/A N/A N/A N/A 1 1 TITLE (include Security Classificarnon) Bounded rationality and organizational learning 12 PERSONAL AUTHOR(S) HretA io 13a...organizations organizational psychology organizational learning bounded rationality cognitive psychology ABSTRACT (Continue on reverse if necessary
Fixed Sagittal Plane Imbalance
Savage, Jason W.; Patel, Alpesh A.
2014-01-01
Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis < 5 cm, pelvic tilt < 20 degrees, and lumbar lordosis equal to pelvic incidence ± 9 degrees. Conclusion Sagittal plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction. PMID:25396111
Fixed sagittal plane imbalance.
Savage, Jason W; Patel, Alpesh A
2014-12-01
Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis < 5 cm, pelvic tilt < 20 degrees, and lumbar lordosis equal to pelvic incidence ± 9 degrees. Conclusion Sagittal plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction.
Optical conductivity of curved graphene.
Chaves, A J; Frederico, T; Oliveira, O; de Paula, W; Santos, M C
2014-05-07
We compute the optical conductivity for an out-of-plane deformation in graphene using an approach based on solutions of the Dirac equation in curved space. Different examples of periodic deformations along one direction translates into an enhancement of the optical conductivity peaks in the region of the far- and mid-infrared frequencies for periodicities ∼100 nm. The width and position of the peaks can be changed by dialling the parameters of the deformation profiles. The enhancement of the optical conductivity is due to intraband transitions and the translational invariance breaking in the geometrically deformed background. Furthermore, we derive an analytical solution of the Dirac equation in a curved space for a general deformation along one spatial direction. For this class of geometries, it is shown that curvature induces an extra phase in the electron wave function, which can also be explored to produce interference devices of the Aharonov-Bohm type.
Critical care rationing: international comparisons.
Evans, Timothy W; Nava, Stefano; Mata, Guillermo Vazquez; Guidet, Bertrand; Estenssoro, Elisa; Fowler, Robert; Scheunemann, Leslie P; White, Douglas; Manthous, Constantine A
2011-12-01
Every country has finite resources that are expended to provide citizens with social "goods," including education, protection, infrastructure, and health care. Rationing-of any resource-refers to distribution of an allotted amount and may involve withholding some goods that would benefit some citizens. Health-care rationing is controversial because good health complements so many human endeavors. We explored (perceptions regarding) critical care rationing in seven industrialized countries. Academic physicians from England, Spain, Italy, France, Argentina, Canada, and the United States wrote essays that addressed specific questions including: (1) What historical, cultural, and medical institutional features inform my country's approach to rationing of health care? (2) What is known about formal rationing, especially in critical care, in my country? (3) How does rationing occur in my ICU? Responses suggest that critical care is rationed, by varying mechanisms, in all seven countries. We speculate that while no single "best" method of rationing is likely to be acceptable or optimal for all countries, professional societies could serve international health by developing evidence-based guidelines for just and effective rationing of critical care.
Rosoff, Philip M
2017-02-01
A principal component of physician decision making is judging what interventions are clinically appropriate. Due to the inexorable and steady increase of health care costs in the US, physicians are constantly being urged to exercise judicious financial stewardship with due regard for the financial implications of what they prescribe. When applied on a case-by-case basis, this otherwise reasonable approach can lead to either inadvertent or overt and arbitrary restriction of interventions for some patients rather than others on the basis of clinically irrelevant characteristics such as ethnicity, gender, age, or skin color. In the absence of systemwide reform in which the resources saved from one patient or group of patients are reallocated for the benefit of others, prudence is urged in the application of "bedside rationing."
Angle measures, general rotations, and roulettes in normed planes
NASA Astrophysics Data System (ADS)
Balestro, Vitor; Horváth, Ákos G.; Martini, Horst
2016-11-01
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.
High speed multi focal plane optical system
NASA Technical Reports Server (NTRS)
Minott, P. O. (Inventor)
1983-01-01
An apparatus for eliminating beamsplitter generated optical aberrations in a pupil concentric optical system providing a plurality of spatially separated images on different focal planes or surfaces is presented. The system employs a buried surface beamsplitter having spherically curved entrance and exit faces which are concentric to a system aperture stop with the entrance face being located in the path of a converging light beam directed there from an image forming objective element which is also concentric to the aperture stop.
Rational Approximations to Rational Models: Alternative Algorithms for Category Learning
ERIC Educational Resources Information Center
Sanborn, Adam N.; Griffiths, Thomas L.; Navarro, Daniel J.
2010-01-01
Rational models of cognition typically consider the abstract computational problems posed by the environment, assuming that people are capable of optimally solving those problems. This differs from more traditional formal models of cognition, which focus on the psychological processes responsible for behavior. A basic challenge for rational models…
Rational Approximations to Rational Models: Alternative Algorithms for Category Learning
ERIC Educational Resources Information Center
Sanborn, Adam N.; Griffiths, Thomas L.; Navarro, Daniel J.
2010-01-01
Rational models of cognition typically consider the abstract computational problems posed by the environment, assuming that people are capable of optimally solving those problems. This differs from more traditional formal models of cognition, which focus on the psychological processes responsible for behavior. A basic challenge for rational models…
Curved Finite Elements and Curve Approximation
NASA Technical Reports Server (NTRS)
Baart, M. L.
1985-01-01
The approximation of parameterized curves by segments of parabolas that pass through the endpoints of each curve segment arises naturally in all quadratic isoparametric transformations. While not as popular as cubics in curve design problems, the use of parabolas allows the introduction of a geometric measure of the discrepancy between given and approximating curves. The free parameters of the parabola may be used to optimize the fit, and constraints that prevent overspill and curve degeneracy are introduced. This leads to a constrained optimization problem in two varibles that can be solved quickly and reliably by a simple method that takes advantage of the special structure of the problem. For applications in the field of computer-aided design, the given curves are often cubic polynomials, and the coefficient may be calculated in closed form in terms of polynomial coefficients by using a symbolic machine language so that families of curves can be approximated with no further integration. For general curves, numerical quadrature may be used, as in the implementation where the Romberg quadrature is applied. The coefficient functions C sub 1 (gamma) and C sub 2 (gamma) are expanded as polynomials in gamma, so that for given A(s) and B(s) the integrations need only be done once. The method was used to find optimal constrained parabolic approximation to a wide variety of given curves.
Evaluation of the Rational Environment
1988-07-01
three evaluations of the Delta release of the Rational Environments. John Devitofran- ceschi took care of the Rational machine at the SEI. Frost...Feiler, P. H., Smeaton , R. The Project Management Experiment: Evaluation of Ada Environments. Technical Report CMU/SEI-88-TR-7, Software Engineering
Sibling Curves and Complex Roots 2: Looking Ahead
ERIC Educational Resources Information Center
Harding, Ansie; Engelbrecht, Johann
2007-01-01
This paper, the second of a two part article, expands on an idea that appeared in literature in the 1950s to show that by restricting the domain to those complex numbers that map onto real numbers, representations of functions other than the ones in the real plane are obtained. In other words, the well-known curves in the real plane only depict…
Optimal strategies for adaptive curve lighting.
Sivak, Michael; Schoettle, Brandon; Flannagan, Michael J; Minoda, Takako
2005-01-01
Conventional low beams headlamps do not provide sufficient illumination for nighttime visibility on curves. This analytical study evaluated the advantages and disadvantages of several curve-lighting strategies that involve moving one or both low beams by various amounts. Two curve radii were examined for both curve directions, using representative tungsten-halogen and high-intensity discharge low-beam patterns. The dependent variable was the maximum distance of 3-lux illumination (combined from both lamps) at a plane 0.25 m above the roadway for seven lateral positions. For short-radius, left and right curves, moving both lamps in parallel should substantially increase the visibility of objects in one's lane of travel, in several additional lanes of travel to the left and right, and off the road. Because of the lateral trade-offs of advantages and disadvantages for large-radius curves, additional research is needed to better understand the desirable approach for these types of curves. Moving both lamps in parallel into the curve is recommended for small-radius curves.
The concept of rational suicide.
Mayo, D J
1986-05-01
Suicide has been condemned in our culture in one way or another since Augustine offered theological arguments against it in the sixth century. More recently, theological condemnation has given way to the view that suicidal behavior must always be symptomatic of emotional disturbance and mental illness. However, suicide has not always been viewed so negatively. In other times and cultures, it has been held that circumstances might befall a person in which suicide would be a perfectly rational course of action, in the same sense that any other course of action could be rational: that it could be sensible, i.e., defensible by good reasons, or that it could be in keeping with the agent's fundamental interests. Indiscriminate use of modern life-sustaining technologies has renewed interest in the possibility of rational suicide. Today proponents of rational suicide tend to equate the rationality of suicide with the competence of the decision to commit suicide.
Lampton, Michael L.; Kim, A.; Akerlof, C.W.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E.; Bebek, C.; Bergstrom, L.; Berkovitz, J.; Bernstein, G.; Bester, M.; Bonissent, A.; Bower, C.; Carithers Jr., W.C.; Commins, E.D.; Day, C.; Deustua, S.E.; DiGennaro,R.; Ealet, A.; Ellis, R.S.; Eriksson, M.; Fruchter, A.; Genat, J.-F.; Goldhaber, G.; Goobar, A.; Groom, D.; Harris, S.E.; Harvey, P.R.; Heetderks, H.D.; Holland, S.E.; Huterer, D.; Karcher, A.; Kolbe, W.; Krieger, B.; Lafever, R.; Lamoureux, J.; Levi, M.E.; Levin, D.S.; Linder,E.V.; Loken, S.C.; Malina, R.; Massey, R.; McKay, T.; McKee, S.P.; Miquel, R.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Nugent, P.; Oluseyi, H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Pratt, R.; Prieto, E.; Refregier, A.; Rhodes, J.; Robinson, K.; Roe, N.; Sholl, M.; Schubnell, M.; Smadja, G.; Smoot, G.; Spadafora, A.; Tarle, G.; Tomasch,A.; von der Lippe, H.; Vincent, R.; Walder, J.-P.; Wang, G.
2002-07-29
The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square-degree field sensitive in the visible and near-infrared wavelength regime. We describe the requirements for the instrument suite and the evolution of the focal plane design to the present concept in which all the instrumentation--visible and near-infrared imagers, spectrograph, and star guiders--share one common focal plane.
Axial Plane Optical Microscopy
Li, Tongcang; Ota, Sadao; Kim, Jeongmin; Wong, Zi Jing; Wang, Yuan; Yin, Xiaobo; Zhang, Xiang
2014-01-01
We present axial plane optical microscopy (APOM) that can, in contrast to conventional microscopy, directly image a sample's cross-section parallel to the optical axis of an objective lens without scanning. APOM combined with conventional microscopy simultaneously provides two orthogonal images of a 3D sample. More importantly, APOM uses only a single lens near the sample to achieve selective-plane illumination microscopy, as we demonstrated by three-dimensional (3D) imaging of fluorescent pollens and brain slices. This technique allows fast, high-contrast, and convenient 3D imaging of structures that are hundreds of microns beneath the surfaces of large biological tissues. PMID:25434770
A Simple Experiment Demonstrating the Relationship between Response Curves and Absorption Spectra.
ERIC Educational Resources Information Center
Li, Chia-yu
1984-01-01
Describes an experiment for recording two individual spectrophotometer response curves. The two curves are directly related to the power of transmitted beams that pass through a solvent and solution. An absorption spectrum of the solution can be constructed from the calculated rations of the curves as a function of wavelength. (JN)
A Simple Experiment Demonstrating the Relationship between Response Curves and Absorption Spectra.
ERIC Educational Resources Information Center
Li, Chia-yu
1984-01-01
Describes an experiment for recording two individual spectrophotometer response curves. The two curves are directly related to the power of transmitted beams that pass through a solvent and solution. An absorption spectrum of the solution can be constructed from the calculated rations of the curves as a function of wavelength. (JN)
Single-shot curved slice imaging.
Jochimsen, Thies H; Norris, David G
2002-03-01
The feasibility of imaging a curved slice with a single-shot technique so that the reconstructed image shows an un-warping of the slice is examined. This could be of practical importance when the anatomical structures of interest can be more efficiently covered with curved slices than with a series of flat planes. One possible example of such a structure is the cortex of the human brain. Functional imaging would especially benefit from this technique because several planar images can be replaced by a few curved slice images. A method is introduced that is based on multidimensional pulses to excite the desired curved slice profile. A GRASE imaging sequence is then applied that is tailored to the k-space representation of the curved slice. This makes it possible to capture the in-plane information of the slice with a single-shot technique. The method presented is limited to slices that are straight along one axis and can be approximated by a polygon. Reconstruction is performed using a simple numeric Fourier integration along the curved slice. This leads to an image that shows the desired un-warped representation of the slice. Experimental results obtained with this method from healthy volunteers are presented and demonstrate the feasibility of the proposed technique.
ERIC Educational Resources Information Center
Greenman, Geri
2001-01-01
Describes an assignment that was used in an advanced drawing class in which the students created self-portraits, breaking up their images using planes and angles to suggest their bone structure. Explains that the students also had to include three realistic portions in their drawings. (CMK)
Rationalizing Hybrid Earthquake Probabilities
NASA Astrophysics Data System (ADS)
Gomberg, J.; Reasenberg, P.; Beeler, N.; Cocco, M.; Belardinelli, M.
2003-12-01
An approach to including stress transfer and frictional effects in estimates of the probability of failure of a single fault affected by a nearby earthquake has been suggested in Stein et al. (1997). This `hybrid' approach combines conditional probabilities, which depend on the time elapsed since the last earthquake on the affected fault, with Poissonian probabilities that account for friction and depend only on the time since the perturbing earthquake. The latter are based on the seismicity rate change model developed by Dieterich (1994) to explain the temporal behavior of aftershock sequences in terms of rate-state frictional processes. The model assumes an infinite population of nucleation sites that are near failure at the time of the perturbing earthquake. In the hybrid approach, assuming the Dieterich model can lead to significant transient increases in failure probability. We explore some of the implications of applying the Dieterich model to a single fault and its impact on the hybrid probabilities. We present two interpretations that we believe can rationalize the use of the hybrid approach. In the first, a statistical distribution representing uncertainties in elapsed and/or mean recurrence time on the fault serves as a proxy for Dieterich's population of nucleation sites. In the second, we imagine a population of nucleation patches distributed over the fault with a distribution of maturities. In both cases we find that the probability depends on the time since the last earthquake. In particular, the size of the transient probability increase may only be significant for faults already close to failure. Neglecting the maturity of a fault may lead to overestimated rate and probability increases.
Brothers, Kyle B
2011-04-01
Provider claims to conscientious objection have generated a great deal of heated debate in recent years. However, the conflicts that arise when providers make claims to the "conscience" are only a subset of the more fundamental challenges that arise in health care practice when patients and providers come into conflict. In this piece, the author provides an account of patient-provider conflict from within the moral tradition of St. Thomas Aquinas. He argues that the practice of health care providers should be understood as a form of practical reasoning and that this practical reasoning must necessarily incorporate both "moral" and "professional" commitments. In order to understand how the practical reasoning of provider should account for the needs and commitments of the patient and vice versa, he explores the account of dependence provided by Alasdair MacIntyre in his book Dependent Rational Animals. MacIntyre argues that St. Thomas' account of practical reasoning should be extended and adapted to account for the embodied vulnerability of all humans. In light of this insight, providers must view patients not only as the subjects of their moral reflection but also as fellow humans upon whom the provider depends for feedback on the effectiveness and relevance of her practical reasoning. The author argues that this account precludes responsive providers from adopting either moral or professional conclusions on the appropriateness of interventions outside the individual circumstances that arise in particular situations. The adoption of this orientation toward patients will neither eradicate provider-patient conflict nor compel providers to perform interventions to which they object. But this account does require that providers attend meaningfully to the suffering of patients and seek feedback on whether their intervention has effectively addressed that suffering.
Laboratory Evaluation of Australian Ration Packs,
in ascorbic acid and thiamin. Ascorbic acid was found to have unsatisfactory storage properties in fortified ration chocolate. Keywords: Field rations, Survival rations, Nutritive value, Food analysis , Food deterioration. (Australia).
From principal curves to granular principal curves.
Zhang, Hongyun; Pedrycz, Witold; Miao, Duoqian; Wei, Zhihua
2014-06-01
Principal curves arising as an essential construct in dimensionality reduction and data analysis have recently attracted much attention from theoretical as well as practical perspective. In many real-world situations, however, the efficiency of existing principal curves algorithms is often arguable, in particular when dealing with massive data owing to the associated high computational complexity. A certain drawback of these constructs stems from the fact that in several applications principal curves cannot fully capture some essential problem-oriented facets of the data dealing with width, aspect ratio, width change, etc. Information granulation is a powerful tool supporting processing and interpreting massive data. In this paper, invoking the underlying ideas of information granulation, we propose a granular principal curves approach, regarded as an extension of principal curves algorithms, to improve efficiency and achieve a sound accuracy-efficiency tradeoff. First, large amounts of numerical data are granulated into C intervals-information granules developed with the use of fuzzy C-means clustering and the two criteria of information granulation, which significantly reduce the amount of data to be processed at the later phase of the overall design. Granular principal curves are then constructed by determining the upper and the lower bounds of the interval data. Finally, we develop an objective function using the criteria of information confidence and specificity to evaluate the granular output formed by the principal curves. We also optimize the granular principal curves by adjusting the level of information granularity (the number of clusters), which is realized with the aid of the particle swarm optimization. A number of numeric studies completed for synthetic and real-world datasets provide a useful quantifiable insight into the effectiveness of the proposed algorithm.
ERIC Educational Resources Information Center
Levinson, Paul
1981-01-01
Looks at McLuhan's method of exploration. Considers why he dismisses logic and traditional rationality, how he supports his stance, and why his contribution to communications media theory is not diminished by his attempt to avoid logical accountability. (PD)
The rationing agenda in the NHS. Rationing Agenda Group.
New, B
1996-06-22
The Rationing Agenda Group has been founded to deepen the British debate on rationing health care. It believes that rationing in health care is inevitable and that the public must be involved in the debate about issues relating to rationing. The group comprises people from all parts of health care, none of whom represent either their group or their institutions. RAG has begun by producing this document, which attempts to set an agenda of all the issues that need to be considered when debating the rationing of health care. We hope for responses to the document. The next stage will be to incorporate the responses into the agenda. Then RAG will divide the agenda into manageable chunks and commission expert, detailed commentaries. From this material a final paper will be published and used to prompt public debate. This stage should be reached early in 1997. While these papers are being prepared RAG is developing ways to involve the public in the debate and evaluate the whole process. We present as neutrally as possible all the issues related to rationing and priority setting in the NHS. We focus on the NHS for two reasons. Firstly, for those of us resident in the United Kingdom the NHS is the health care system with which we are most familiar and most concerned. Secondly, focusing on one system alone allows more coherent analysis than would be possible if issues in other systems were included as well. Our concern is with the delivery of health care, not its finance, though we discuss the possible effects of changing the financing system of the NHS. Finally, though our position is neutral, we hold two substantive views--namely, that rationing is unavoidable and that there should be more explicit debate about the principles and issues concerned. We consider the issues under four headings: preliminaries, ethics, democracy, and empirical questions. Preliminaries deal with the semantics of rationing, whether rationing is necessary, and with the range of services to which
The rationing agenda in the NHS. Rationing Agenda Group.
New, B.
1996-01-01
The Rationing Agenda Group has been founded to deepen the British debate on rationing health care. It believes that rationing in health care is inevitable and that the public must be involved in the debate about issues relating to rationing. The group comprises people from all parts of health care, none of whom represent either their group or their institutions. RAG has begun by producing this document, which attempts to set an agenda of all the issues that need to be considered when debating the rationing of health care. We hope for responses to the document. The next stage will be to incorporate the responses into the agenda. Then RAG will divide the agenda into manageable chunks and commission expert, detailed commentaries. From this material a final paper will be published and used to prompt public debate. This stage should be reached early in 1997. While these papers are being prepared RAG is developing ways to involve the public in the debate and evaluate the whole process. We present as neutrally as possible all the issues related to rationing and priority setting in the NHS. We focus on the NHS for two reasons. Firstly, for those of us resident in the United Kingdom the NHS is the health care system with which we are most familiar and most concerned. Secondly, focusing on one system alone allows more coherent analysis than would be possible if issues in other systems were included as well. Our concern is with the delivery of health care, not its finance, though we discuss the possible effects of changing the financing system of the NHS. Finally, though our position is neutral, we hold two substantive views--namely, that rationing is unavoidable and that there should be more explicit debate about the principles and issues concerned. We consider the issues under four headings: preliminaries, ethics, democracy, and empirical questions. Preliminaries deal with the semantics of rationing, whether rationing is necessary, and with the range of services to which
Data reduction using cubic rational B-splines
NASA Technical Reports Server (NTRS)
Chou, Jin J.; Piegl, Les A.
1992-01-01
A geometric method is proposed for fitting rational cubic B-spline curves to data that represent smooth curves including intersection or silhouette lines. The algorithm is based on the convex hull and the variation diminishing properties of Bezier/B-spline curves. The algorithm has the following structure: it tries to fit one Bezier segment to the entire data set and if it is impossible it subdivides the data set and reconsiders the subset. After accepting the subset the algorithm tries to find the longest run of points within a tolerance and then approximates this set with a Bezier cubic segment. The algorithm uses this procedure repeatedly to the rest of the data points until all points are fitted. It is concluded that the algorithm delivers fitting curves which approximate the data with high accuracy even in cases with large tolerances.
Data reduction using cubic rational B-splines
NASA Technical Reports Server (NTRS)
Chou, Jin J.; Piegl, Les A.
1992-01-01
A geometric method is proposed for fitting rational cubic B-spline curves to data that represent smooth curves including intersection or silhouette lines. The algorithm is based on the convex hull and the variation diminishing properties of Bezier/B-spline curves. The algorithm has the following structure: it tries to fit one Bezier segment to the entire data set and if it is impossible it subdivides the data set and reconsiders the subset. After accepting the subset the algorithm tries to find the longest run of points within a tolerance and then approximates this set with a Bezier cubic segment. The algorithm uses this procedure repeatedly to the rest of the data points until all points are fitted. It is concluded that the algorithm delivers fitting curves which approximate the data with high accuracy even in cases with large tolerances.
Space plane navigation simulation
NASA Astrophysics Data System (ADS)
Matsushima, Koichi; Murata, Masaaki; Shingu, Hirokimi; Shimizu, Tetsuo; Mikami, Tatsuo; Hashida, Yoshikazu
A simulation program for a future Japanese space-plane (SP) considered for development is presented along with the results of the analysis of a candidate navigation configuration, focused on the terminal area energy management phase and the approach/landing phase of SP. The guidance laws and aerodynamic parameters which are applied to the program for the analysis are modeled using the laws and parameters of the U.S. Space Suttle, assuming typical values for the accuracy of sensors.
1989-03-01
Th usr a toente aninteer a thca sms b esta 1 Fp-ocsing 2. Enter P1 values, lwgt, ldig - > 9 Table I give us proper values. Table 1. PARAMETER TABLE...necessary and identify by block number) In this thesis a control systems analysis package is developed using parameter plane methods. It is an interactive...designer is able to choose values of the parameters which provide a good compromise between cost and dynamic behavior. 20 Distribution Availability of
Mustard meal in dairy rations.
Moss, B R
1975-11-01
Consumption of 0% mustard meal and 15% soybean meal, 7.5% mustard meal and 7.5% soybean meal, or 15% mustard meal and 0% soybean meal rations did not differ in palatability studies with 10 group-fed lactating cows when the mustard meal was treated with 3% caustic soda. Order of preference was for 0, 7.5, and 15% mustard meal rations when mustard meal was untreated. Twelve lactating cows were in each of two lactation trials to compare the three rations of untreated mustard meal. Milk, milk fat, and solids-not-fat, and milk protein did not differ for either trial. Protein-bound iodine of plasma for all cows were within the normal range. Three cows were placed on each of the three rations and received a minimum of 9 kg per day for 6 mo preparturition to determine goitrogenic effects. All cows gave birth to normal, vigorous calves. Limited organoleptic evaluations of milk indicated that untreated mustard meal may impart a detrimental flavor to milk, but a taste panel could not differentiate between milk from cows on the three rations of treated mustard meal. Twenty-one male and 43 female Holstein claves received either 0, 10, or 20% mustard meal starter rations from birth to 3 mo of age. Growth, feed consumption, or plasma protein-bound iodine did not differ.
A method of plane geometry primitive presentation
NASA Astrophysics Data System (ADS)
Jiao, Anbo; Luo, Haibo; Chang, Zheng; Hui, Bin
2014-11-01
Point feature and line feature are basic elements in object feature sets, and they play an important role in object matching and recognition. On one hand, point feature is sensitive to noise; on the other hand, there are usually a huge number of point features in an image, which makes it complex for matching. Line feature includes straight line segment and curve. One difficulty in straight line segment matching is the uncertainty of endpoint location, the other is straight line segment fracture problem or short straight line segments joined to form long straight line segment. While for the curve, in addition to the above problems, there is another difficulty in how to quantitatively describe the shape difference between curves. Due to the problems of point feature and line feature, the robustness and accuracy of target description will be affected; in this case, a method of plane geometry primitive presentation is proposed to describe the significant structure of an object. Firstly, two types of primitives are constructed, they are intersecting line primitive and blob primitive. Secondly, a line segment detector (LSD) is applied to detect line segment, and then intersecting line primitive is extracted. Finally, robustness and accuracy of the plane geometry primitive presentation method is studied. This method has a good ability to obtain structural information of the object, even if there is rotation or scale change of the object in the image. Experimental results verify the robustness and accuracy of this method.
Boyer, H.E.
1986-01-01
This book contains more than 500 fatigue curves for industrial ferrous and nonferrous alloys. It also includes a thorough explanation of fatigue testing and interpretation of test results. Each curve is presented independently and includes an explanation of its particular importance. The curves are titled by standard industrial designations (AISI, CDA, AA, etc.) of the metals, and a complete reference is given to the original source to facilitate further research. The collection includes standard S-N curves, curves showing effect of surface hardening on fatigue strength, crack growth-rate curves, curves comparing the fatigue strengths of various alloys, effect of variables (i,e, temperature, humidity, frequency, aging, environment, etc.) and much, much more. This one volume consolidates the fatigue data in a single source.
Computing Riemann matrices of algebraic curves
NASA Astrophysics Data System (ADS)
Deconinck, Bernard; van Hoeij, Mark
2001-05-01
A black-box program for the explicit calculation of Riemann matrices of arbitrary compact connected Riemann surfaces is presented. All such Riemann surfaces are represented as plane algebraic curves. These algebraic curves are allowed to have arbitrary singularities. The method of calculation of the Riemann matrix is essentially its definition: we numerically integrate the holomorphic differentials of the Riemann surface over the cycles of a canonical basis of the homology of the Riemann surface. Both the holomorphic differentials and the canonical basis of the homology of the Riemann surface are obtained exactly through symbolic calculations. This program is included in Maple 6, as part of the algcurves package.
Bacterial streamers in curved microchannels
NASA Astrophysics Data System (ADS)
Rusconi, Roberto; Lecuyer, Sigolene; Guglielmini, Laura; Stone, Howard
2009-11-01
Biofilms, generally identified as microbial communities embedded in a self-produced matrix of extracellular polymeric substances, are involved in a wide variety of health-related problems ranging from implant-associated infections to disease transmissions and dental plaque. The usual picture of these bacterial films is that they grow and develop on surfaces. However, suspended biofilm structures, or streamers, have been found in natural environments (e.g., rivers, acid mines, hydrothermal hot springs) and are always suggested to stem from a turbulent flow. We report the formation of bacterial streamers in curved microfluidic channels. By using confocal laser microscopy we are able to directly image and characterize the spatial and temporal evolution of these filamentous structures. Such streamers, which always connect the inner corners of opposite sides of the channel, are always located in the middle plane. Numerical simulations of the flow provide evidences for an underlying hydrodynamic mechanism behind the formation of the streamers.
Lower extremity kinematics of athletics curve sprinting.
Alt, Tobias; Heinrich, Kai; Funken, Johannes; Potthast, Wolfgang
2015-01-01
Curve running requires the generation of centripetal force altering the movement pattern in comparison to the straight path run. The question arises which kinematic modulations emerge while bend sprinting at high velocities. It has been suggested that during curve sprints the legs fulfil different functions. A three-dimensional motion analysis (16 high-speed cameras) was conducted to compare the segmental kinematics of the lower extremity during the stance phases of linear and curve sprints (radius: 36.5 m) of six sprinters of national competitive level. Peak joint angles substantially differed in the frontal and transversal plane whereas sagittal plane kinematics remained unchanged. During the prolonged left stance phase (left: 107.5 ms, right: 95.7 ms, straight: 104.4 ms) the maximum values of ankle eversion (left: 12.7°, right: 2.6°, straight: 6.6°), hip adduction (left: 13.8°, right: 5.5°, straight: 8.8°) and hip external rotation (left: 21.6°, right: 12.9°, straight: 16.7°) were significantly higher. The inside leg seemed to stabilise the movement in the frontal plane (eversion-adduction strategy) whereas the outside leg provided and controlled the motion in the horizontal plane (rotation strategy). These results extend the principal understanding of the effects of curve sprinting on lower extremity kinematics. This helps to increase the understanding of nonlinear human bipedal locomotion, which in turn might lead to improvements in athletic performance and injury prevention.
"The Bell Curve": Ringing in the Contract with America.
ERIC Educational Resources Information Center
Farrell, Walter C., Jr.; And Others
1995-01-01
Herrnstein and Murray's "The Bell Curve" claims that IQ is hereditary and that African Americans consistently score 15 points lower than other racial groups. Coolly received by academics, the book is being warmly embraced by Republican politicians endorsing fiscal austerity and social mean-spiritedness. The book rationalizes a…
Curve and surface construction using Hermite subdivision schemes
NASA Astrophysics Data System (ADS)
Costantini, Paolo; Manni, Carla
2010-02-01
In this paper we present a very efficient Hermite subdivision scheme, based on rational functions, and outline its potential applications, with special emphasis on the construction of cubic-like B-splines -- well suited for the design of constrained curves and surfaces.
Partially Blended Constrained Rational Cubic Trigonometric Fractal Interpolation Surfaces
NASA Astrophysics Data System (ADS)
Chand, A. K. B.; Tyada, K. R.
2016-08-01
Fractal interpolation is an advance technique for visualization of scientific shaped data. In this paper, we present a new family of partially blended rational cubic trigonometric fractal interpolation surfaces (RCTFISs) with a combination of blending functions and univariate rational trigonometric fractal interpolation functions (FIFs) along the grid lines of the interpolation domain. The developed FIFs use rational trigonometric functions pi,j(θ) qi,j(θ), where pi,j(θ) and qi,j(θ) are cubic trigonometric polynomials with four shape parameters. The convergence analysis of partially blended RCTFIS with the original surface data generating function is discussed. We derive sufficient data-dependent conditions on the scaling factors and shape parameters such that the fractal grid line functions lie above the grid lines of a plane Π, and consequently the proposed partially blended RCTFIS lies above the plane Π. Positivity preserving partially blended RCTFIS is a special case of the constrained partially blended RCTFIS. Numerical examples are provided to support the proposed theoretical results.
Analysis of Basal Plane Bending and Basal Plane Dislocations in 4H-SiC Single Crystals
NASA Astrophysics Data System (ADS)
Ohtani, Noboru; Katsuno, Masakazu; Fujimoto, Tatsuo; Nakabayashi, Masashi; Tsuge, Hiroshi; Yashiro, Hirokatsu; Aigo, Takashi; Hirano, Hosei; Hoshino, Taizo; Ohashi, Wataru
2009-06-01
4H-SiC single crystals were grown by the physical vapor transport (PVT) growth method under different thermoelastic stress conditions, and the degree of basal plane bending in the crystals was characterized by the peak shift measurement of X-ray rocking curves. The results indicate that the degree of basal plane bending largely depends on the magnitude of the thermoelastic stresses imposed on the crystals during PVT growth. Quantitative analysis of basal plane bending revealed that the density of basal plane dislocations (BPDs) estimated from basal plane bending is much smaller than that obtained from defect-selective etching. It was also found that the BPD density is correlated with the threading screw dislocation (TSD) density in PVT-grown SiC crystals. These aspects of BPDs were discussed in terms of the BPD multiplication process triggered by the intersection of BPDs with a forest of TSDs extending along the c-axis.
Turbulence measurements in curved wall jets
NASA Astrophysics Data System (ADS)
Rodman, L. C.; Wood, N. J.; Roberts, L.
1987-01-01
Accurate turbulence measurements taken in wall jet flows are difficult to obtain, due to high intensity turbulence and problems in achieving two-dimensionality. The problem is compounded when streamwise curvature of the flow is introduced, since the jet entrainment and turbulence levels are greatly increased over the equivalent planar values. In this experiment, two-dimensional plane and curved wall jet flows are simulated by having a jet blow axially over a cylinder. In the plane case the cylinder has constant transverse radius, and in the curved cases the cylinder has a varying transverse radius. Although the wall jet in these cases is axisymmetric, adequate 'two-dimensional' flow can be obtained as long as the ratio of the jet width to the cylinder radius is small. The annular wall jet has several advantages over wall jets issuing from finite rectangular slots. Since the slot has no ends, three-dimensional effects caused by the finite length of the slot and side wall interference are eliminated. Also, the transverse curvature of the wall allows close optical access to the surface using a Laser Doppler Velocimetry (LDV) system. Hot wire measurements and some LDV measurements are presented for plane and curved wall jet flows. An integral analysis is used to assess the effects of transverse curvature on the turbulent shear stress. The analysis and the data show that the effects of transverse curvature on both the mean flow and the shear stress are small enough for two-dimensional flow to be approximately satisfactorily.
NASA Technical Reports Server (NTRS)
Zahm, A F
1924-01-01
This report gives the description and the use of a specially designed aerodynamic plane table. For the accurate and expeditious geometrical measurement of models in an aerodynamic laboratory, and for miscellaneous truing operations, there is frequent need for a specially equipped plan table. For example, one may have to measure truly to 0.001 inch the offsets of an airfoil at many parts of its surface. Or the offsets of a strut, airship hull, or other carefully formed figure may require exact calipering. Again, a complete airplane model may have to be adjusted for correct incidence at all parts of its surfaces or verified in those parts for conformance to specifications. Such work, if but occasional, may be done on a planing or milling machine; but if frequent, justifies the provision of a special table. For this reason it was found desirable in 1918 to make the table described in this report and to equip it with such gauges and measures as the work should require.
Hackel, L.A.; Hermann, M.R.; Dane, C.B.; Tiszauer, D.H.
1995-12-12
A solid state laser is frequency tripled to 0.3 {micro}m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only about 1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power. 1 fig.
Hackel, Lloyd A.; Hermann, Mark R.; Dane, C. Brent; Tiszauer, Detlev H.
1995-01-01
A solid state laser is frequency tripled to 0.3 .mu.m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only .about.1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power.
Curved infrared detectors: application to spectrometry and astronomy
NASA Astrophysics Data System (ADS)
Dumas, D.; Fendler, M.; Berger, F.; Marion, F.; Arnaud, A.; Vialle, C.; Goudon, V.; Primot, J.; Le Coarer, E.; Ribot, H.
2010-07-01
The traditional design of optical systems is severely complicated by the curved shape of the image surface which has to be recorded on a planar retina. This constraint decreases the image quality; optical elements are then added to avoid aberrations and lead to increase the dimensions of the system. However, miniaturization could be achieved, without decreasing resolution and sensibility, by recording the image surface on a curved retina. The optical advantages of curved sensors have been demonstrated; the simplification leads to scale down the entire system. Moreover, the hemispherical shape increases the field of view (FOV). In this paper the advantages of curved focal plane will be detailed through two applications: spectrometry and large FOV telescopes. In astronomy, large FOV and miniaturization with good resolution can only be achieved by curving the focal plane; the difficulty is to curve in a hemispherical shape large detectors. The advantages are highlighted by the European Extremely Large Telescope (E-ELT) project. Despite this high interest in curved detectors, only few articles are dedicated to this hemispherical shape technology. Some solutions exist, which mainly consist in structuring the die in sub-devices. We propose a solution to curve an IR sensor with a fill factor equal to 100%. To do so, we developed a dedicated bonding process which allows curving silicon using its mechanical properties. A curved uncooled infrared detector has been performed without mechanical and electrical damage.
NASA Technical Reports Server (NTRS)
Jackson, Wade C.; Portanova, Marc A.
1995-01-01
This paper summarizes three areas of research which were performed to characterize out-of-plane properties of composite materials. In the first investigation, a series of tests was run to characterize the through-the-thickness tensile strength for a variety of composites that included 2D braids, 2D and 3D weaves, and prepreg tapes. A new test method based on a curved beam was evaluated. Failures were significantly different between the 2D materials and the 3D weaves. The 2D materials delaminated between layers due to out-of-plane tensile stresses while the 3D weaves failed due to the formation of radial cracks between the surface plies caused by high circumferential stresses along the inner radius. The strength of the 2D textile composites did not increase relative to the tapes. Final failure in the 3D weaves was caused by a circumferential crack similar to the 2D materials and occurred at a lower bending moment than in other materials. The early failures in the 3D weaves were caused by radial crack formation rather than a low through-the-thickness strength. The second investigation focused on the development of a standard impact test method to measure impact damage resistance. The only impact tests that currently exist are compression after impact (CAI) tests which incorporate elements of both damage resistance and damage tolerance. A new impact test method is under development which uses a quasi-static indentation (QSI) test to directly measure damage resistance. Damage resistance is quantified in terms of the contact force to produce a unit of damage where a metric for damage may be area in C-scan, depth of residual dent , penetration, damage growth, etc. A final draft of an impact standard that uses a QSI test method will be presented to the ASTM Impact Task Group on impact. In the third investigation, the impact damage resistance behavior of a variety of textile materials was studied using the QSI test method. In this study, the force where large damage
Jackson, W.C.; Portanova, M.A.
1995-10-01
This paper summarizes three areas of research which were performed to characterize out-of-plane properties of composite materials. In the first investigation, a series of tests was run to characterize the through-the-thickness tensile strength for a variety of composites that included 2D braids, 2D and 3D weaves, and prepreg tapes. A new test method based on a curved beam was evaluated. Failures were significantly different between the 2D materials and the 3D weaves. The 2D materials delaminated between layers due to out-of-plane tensile stresses while the 3D weaves failed due to the formation of radial cracks between the surface plies caused by high circumferential stresses along the inner radius. The strength of the 2D textile composites did not increase relative to the tapes. Final failure in the 3D weaves was caused by a circumferential crack similar to the 2D materials and occurred at a lower bending moment than in other materials. The early failures in the 3D weaves were caused by radial crack formation rather than a low through-the-thickness strength. The second investigation focused on the development of a standard impact test method to measure impact damage resistance. The only impact tests that currently exist are compression after impact (CAI) tests which incorporate elements of both damage resistance and damage tolerance. A new impact test method is under development which uses a quasi-static indentation (QSI) test to directly measure damage resistance. Damage resistance is quantified in terms of the contact force to produce a unit of damage where a metric for damage may be area in C-scan, depth of residual dent, penetration, damage growth, etc. A final draft of an impact standard that uses a QSI test method will be presented to the ASTM Impact Task Group on impact. In the third investigation, the impact damage resistance behavior of a variety of textile materials was studied using the QSI test method.
Shaped curve by blending two circular arcs
NASA Astrophysics Data System (ADS)
Zakaria, Wan Zafira Ezza Wan; Ali, Jamaludin Md
2014-07-01
Segments of two given circular arcs can be blended to produce a segment of a new curve. The new curve that been produced which also known as blending curve is form in a C-shape. That's mean the two circular arcs are blend at the same endpoints. Bezier Curve refer to [1] is the main application in this construction of blending curve. As the two circular arcs are create using the Rational Bezier Curve for the shape refer to [2]. First degree of Bezier Curve is use in blending function along with functionH(t). Blending can provide a smooth transition from one curve to another and can give various degrees of smoothness at the endpoints of the blend, where the smoothness is measured analogously to parametric continuity, Cn and geometric continuity, Gn. The accuracy of the approximation to a best blending curve obtained by different blending formulas is compared via analysis. Two types of blending formula introduced, which are Blend A and B. Blend A which involve only parametric continuity, C0, C1 and C2 Blend A. Next, new blending formula known as Blend B which actually a correction to the C0 Blend A. So, some correction term are added to the blending function in C0 Blend A for obtaining parametric continuity, C1 and C2 Blend B. Then, geometric continuity use for Blend B by increasing the smoothness of blending curve that result in parametric continuity. Some free parameter are added to the original blending function of C1 and C2 Blend B and secure to be G1 and G2 Blend B. Finally, the curvature which measures how quickly a tangent line turns on a curve is applied. So, appropriate result of blending curve can be obtained through the observation of the shape which lies within the convex hull of their control points and its curvature value at the start and end points equal to the curvature of the two circular arcs that are being blended.
Rationalizing the Promotion of Non-Rational Behaviors in Organizations.
ERIC Educational Resources Information Center
Smith, Peter A. C.; Sharma, Meenakshi
2002-01-01
Organizations must balance rational/technical efficiency and emotions. Action learning has been proven to be effective for developing emotional openness in the workplace. Facilitators of action learning should draw upon the disciplines of counseling, Gestalt, psychodynamics, and Eastern philosophies. (Contains 23 references.) (SK)
Mental health as rational autonomy.
Edwards, R B
1981-08-01
Rather than eliminate the terms "mental health and illness" because of the grave moral consequences of psychiatric labeling, conservative definitions are proposed and defended. Mental health is rational autonomy, and mental illness is the sustained loss of such. Key terms are explained, advantages are explored, and alternative concepts are criticized. The value and descriptive components of all such definitions are consciously acknowledged. Where rational autonomy is intact, mental hospitals and psychotherapists should not think of themselves as treating an illness. Instead, they are functioning as applied axiologists, moral educators, spiritual mentors, etc. They deal with what Szasz has called "personal, social, and ethical problems in living." But mental illness is real.
Spectral Methods Using Rational Basis Functions on an Infinite Interval
NASA Astrophysics Data System (ADS)
Boyd, John P.
1987-03-01
By using the map y = L cot( t) where L is a constant, differential equations on the interval yɛ [- ∞, ∞] can be transformed into tɛ [0, π] and solved by an ordinary Fourier series. In this article, earlier work by Grosch and Orszag ( J. Comput. Phys.25, 273 (1977)), Cain, Ferziger, and Reynolds ( J. Comput. Phys.56, 272 (1984)), and Boyd ( J. Comput. Phys.25, 43 (1982); 57, 454 (1985); SIAM J. Numer. Anal. (1987)) is extended in several ways. First, the series of orthogonal rational functions converge on the exterior of bipolar coordinate surfaces in the complex y-plane. Second, Galerkin's method will convert differential equations with polynomial or rational coefficients into banded matrix problems. Third, with orthogonal rational functions it is possible to obtain exponential convergence even for u( y) that asymptote to a constant although this behavior would wreck alternatives such as Hermite or sinc expansions. Fourth, boundary conditions are usually "natural" rather than "essential" in the sense that the singularities of the differential equation will force the numerical solution to have the correct behavior at infinity even if no constraints are imposed on the basis functions. Fifth, mapping a finite interval to an infinite one and then applying the rational Chebyshev functions gives an exponentially convergent method for functions with bounded endpoint singularities. These concepts are illustrated by five numerical examples.
Approximating rational triangular Bézier surfaces by polynomial triangular Bézier surfaces
NASA Astrophysics Data System (ADS)
Xu, Hui-Xia; Wang, Guo-Jin
2009-06-01
An attractive method for approximating rational triangular Bézier surfaces by polynomial triangular Bézier surfaces is introduced. The main result is that the arbitrary given order derived vectors of a polynomial triangular surface converge uniformly to those of the approximated rational triangular Bézier surface as the elevated degree tends to infinity. The polynomial triangular surface is constructed as follows. Firstly, we elevate the degree of the approximated rational triangular Bézier surface, then a polynomial triangular Bézier surface is produced, which has the same order and new control points of the degree-elevated rational surface. The approximation method has theoretical significance and application value: it solves two shortcomings-fussy expression and uninsured convergence of the approximation-of Hybrid algorithms for rational polynomial curves and surfaces approximation.
Plane-strain tension tests on aluminum alloy sheet
Taha, F.; Hosford, W.; Graf, A.
1995-04-01
A simple way of making plane-strain tension tests on sheet specimens has been developed. This method was used to test sheets of aluminum alloy 2008 T4 and the results were analyzed in terms of a high exponent yield criterion and isotropic hardening. Experimentally measured forces agreed with those calculated from strain measurements using uniaxial tension test curves.
Proposal of a new plane shape of an opera house-optimized by genetic algorithms
NASA Astrophysics Data System (ADS)
Hotehama, Takuya; Ando, Yoichi; Tani, Akinori; Kawamura, Hiroshi
2004-05-01
The horseshoe-shaped theater has been the main shape from historical circumstances. However, from acoustical points of view, the rationality of the peculiar plane shape is not yet verified more than historical refinement. In this study, in order to make the theater shape more acoustically excellent, optimization for temporal and spatial factors in the theory of the subjective preference was made using genetic algorithms (GAs) by operating the positions of side walls. Results reconfirm that the plane shape of the optimized theater is a leaf shape, which has been verified to be acoustically rational in a concert hall. And, further possible shapes are also offered.
ERIC Educational Resources Information Center
Martínez, Sol Sáez; de la Rosa, Félix Martínez; Rojas, Sergio
2017-01-01
In Advanced Calculus, our students wonder if it is possible to graphically represent a tornado by means of a three-dimensional curve. In this paper, we show it is possible by providing the parametric equations of such tornado-shaped curves.
ERIC Educational Resources Information Center
Martínez, Sol Sáez; de la Rosa, Félix Martínez; Rojas, Sergio
2017-01-01
In Advanced Calculus, our students wonder if it is possible to graphically represent a tornado by means of a three-dimensional curve. In this paper, we show it is possible by providing the parametric equations of such tornado-shaped curves.
ERIC Educational Resources Information Center
Nordmark, Arne; Essen, Hanno
2007-01-01
The equilibrium of a flexible inextensible string, or chain, in the centrifugal force field of a rotating reference frame is investigated. It is assumed that the end points are fixed on the rotation axis. The shape of the curve, the skipping rope curve or "troposkien", is given by the Jacobi elliptic function sn. (Contains 3 figures.)
Simulating Supernova Light Curves
Even, Wesley Paul; Dolence, Joshua C.
2016-05-05
This report discusses supernova light simulations. A brief review of supernovae, basics of supernova light curves, simulation tools used at LANL, and supernova results are included. Further, it happens that many of the same methods used to generate simulated supernova light curves can also be used to model the emission from fireballs generated by explosions in the earth’s atmosphere.
Searcy, James Kincheon
1959-01-01
The flow-duration curve is a cumulative frequency curve that shows the percent of time specified discharges were equaled or exceeded during a given period. It combines in one curve the flow characteristics of a stream throughout the range of discharge, without regard to the sequence of occurrence. If the period upon which the curve is based represents the long-term flow of a stream, the curve may be used to predict the distribution of future flows for water- power, water-supply, and pollution studies. This report shows that differences in geology affect the low-flow ends of flow-duration curves of streams in adjacent basins. Thus, duration curves are useful in appraising the geologic characteristics of drainage basins. A method for adjusting flow-duration curves of short periods to represent long-term conditions is presented. The adjustment is made by correlating the records of a short-term station with those of a long-term station.
ERIC Educational Resources Information Center
Nordmark, Arne; Essen, Hanno
2007-01-01
The equilibrium of a flexible inextensible string, or chain, in the centrifugal force field of a rotating reference frame is investigated. It is assumed that the end points are fixed on the rotation axis. The shape of the curve, the skipping rope curve or "troposkien", is given by the Jacobi elliptic function sn. (Contains 3 figures.)
Anodic Polarization Curves Revisited
ERIC Educational Resources Information Center
Liu, Yue; Drew, Michael G. B.; Liu, Ying; Liu, Lin
2013-01-01
An experiment published in this "Journal" has been revisited and it is found that the curve pattern of the anodic polarization curve for iron repeats itself successively when the potential scan is repeated. It is surprising that this observation has not been reported previously in the literature because it immediately brings into…
Focal plane polarimeter design
McClelland, J.B.
1983-10-12
Measurement of polarization transfer or so-called triple-scattering parameters have been made recently for proton-nucleon scattering at TRIUMF, SIN, and LAMPF using carbon polarimeters and have been essential in determining the proton-nucleon amplitudes up to 800 MeV. An extension to the case is described where the scattered proton polarization is analyzed after passage through some type of spectrometer. Most of the experience with this type of focal plane polarimeter (FPP) has been gained in the field of proton-nucleus scattering at intermediate energies but is certainly not confined to such specific cases. The salient features of an FPP are emphasized by describing a minimal system which includes all the necessary components then go on to a more complete system. 10 references. (WHK)
NASA Technical Reports Server (NTRS)
1999-01-01
Excerpt from the NASA Connect show 'Plane Weather' This clip explains what high and low pressure weather systems are, and how these affect weather patterns. Weather affects our daily lives. The elements of weather: rain, wind, fog, ice and snow affect the operation and flight of an airplane. In this program, NASA and FAA researchers will introduce students to math, science, and weather; demonstrate how these elements influence flight; and show how NASA and FAA research is used to limit the effects of these elements on flight. Students will examine: the tools, techniques, and technologies used by engineers and scientists to detect these and other climatological factors affecting aircraft in flight. The lesson and classroom experiment will involve students in the scientific process and emphasizing problem solving, measurement, and reasoning skills.
CURVES: curve evolution for vessel segmentation.
Lorigo, L M; Faugeras, O D; Grimson, W E; Keriven, R; Kikinis, R; Nabavi, A; Westin, C F
2001-09-01
The vasculature is of utmost importance in neurosurgery. Direct visualization of images acquired with current imaging modalities, however, cannot provide a spatial representation of small vessels. These vessels, and their branches which show considerable variations, are most important in planning and performing neurosurgical procedures. In planning they provide information on where the lesion draws its blood supply and where it drains. During surgery the vessels serve as landmarks and guidelines to the lesion. The more minute the information is, the more precise the navigation and localization of computer guided procedures. Beyond neurosurgery and neurological study, vascular information is also crucial in cardiovascular surgery, diagnosis, and research. This paper addresses the problem of automatic segmentation of complicated curvilinear structures in three-dimensional imagery, with the primary application of segmenting vasculature in magnetic resonance angiography (MRA) images. The method presented is based on recent curve and surface evolution work in the computer vision community which models the object boundary as a manifold that evolves iteratively to minimize an energy criterion. This energy criterion is based both on intensity values in the image and on local smoothness properties of the object boundary, which is the vessel wall in this application. In particular, the method handles curves evolving in 3D, in contrast with previous work that has dealt with curves in 2D and surfaces in 3D. Results are presented on cerebral and aortic MRA data as well as lung computed tomography (CT) data.
Development of the curve of Spee.
Marshall, Steven D; Caspersen, Matthew; Hardinger, Rachel R; Franciscus, Robert G; Aquilino, Steven A; Southard, Thomas E
2008-09-01
Ferdinand Graf von Spee is credited with characterizing human occlusal curvature viewed in the sagittal plane. This naturally occurring phenomenon has clinical importance in orthodontics and restorative dentistry, yet we have little understanding of when, how, or why it develops. The purpose of this study was to expand our understanding by examining the development of the curve of Spee longitudinally in a sample of untreated subjects with normal occlusion from the deciduous dentition to adulthood. Records of 16 male and 17 female subjects from the Iowa Facial Growth Study were selected and examined. The depth of the curve of Spee was measured on their study models at 7 time points from ages 4 (deciduous dentition) to 26 (adult dentition) years. The Wilcoxon signed rank test was used to compare changes in the curve of Spee depth between time points. For each subject, the relative eruption of the mandibular teeth was measured from corresponding cephalometric radiographs, and its contribution to the developing curve of Spee was ascertained. In the deciduous dentition, the curve of Spee is minimal. At mean ages of 4.05 and 5.27 years, the average curve of Spee depths are 0.24 and 0.25 mm, respectively. With change to the transitional dentition, corresponding to the eruption of the mandibular permanent first molars and central incisors (mean age, 6.91 years), the curve of Spee depth increases significantly (P < 0.0001) to a mean maximum depth of 1.32 mm. The curve of Spee then remains essentially unchanged until eruption of the second molars (mean age, 12.38 years), when the depth increases (P < 0.0001) to a mean maximum depth of 2.17 mm. In the adolescent dentition (mean age, 16.21 years), the depth decreases slightly (P = 0.0009) to a mean maximum depth of 1.98 mm, and, in the adult dentition (mean age 26.98 years), the curve remains unchanged (P = 0.66), with a mean maximum depth of 2.02 mm. No significant differences in curve of Spee development were found between
Rational Suicide among the Elderly.
ERIC Educational Resources Information Center
Humphry, Derek
1992-01-01
Contends that old age, in and of itself, should never need to be a cause for self-destruction. Further argues that suicide and assisted suicide carried out in the face of terminal illness causing unbearable suffering should be ethically and legally acceptable. Outlines a perspective on rational suicide among the elderly. (Author/NB)
Rational Exponentials and Continued Fractions
ERIC Educational Resources Information Center
Denny, J. K.
2012-01-01
Using continued fraction expansions, we can approximate constants, such as pi and e, using an appropriate integer n raised to the power x[superscript 1/x], x a suitable rational. We review continued fractions and give an algorithm for producing these approximations.
Rational Suicide among the Elderly.
ERIC Educational Resources Information Center
Humphry, Derek
1992-01-01
Contends that old age, in and of itself, should never need to be a cause for self-destruction. Further argues that suicide and assisted suicide carried out in the face of terminal illness causing unbearable suffering should be ethically and legally acceptable. Outlines a perspective on rational suicide among the elderly. (Author/NB)
Rational suicide: uncertain moral ground.
Rich, Karen L; Butts, Janie B
2004-05-01
The ambiguities involving end-of-life issues, such as physician-assisted suicide and voluntary stopping of eating and drinking, have caused a blurring of the definition of rational suicide and have prompted rich dialogue with moral deliberations that seem to be on disparate paths among bioethicists and other health care professionals. With the evolution of advanced medical technology extending life expectancy in older, disabled, and terminally ill people, rational suicide has become a critical issue of debate. The purpose of this article is to address the ethical positions supporting and opposing rational suicide and to consider whether coherence can be achieved through an ethic of care. Attitudes towards suicide have been controversial, varying from acceptance to non-acceptance depending on social, political and religious influences. Nursing attitudes are no different from general societal attitudes and, consequently, nurses are treading on uncertain moral ground. Nurses who have not reflected on the moral issues involved with rational suicide may be unprepared psychologically and professionally when working with patients who may be contemplating such actions.
Rational Normalization of Concentration Measures.
ERIC Educational Resources Information Center
Bonckaert, P.; Egghe, L.
1991-01-01
Discusses normalization features of good concentration measures and extends the range of values of concentration measures that are population-size-independent. Rational normalization is described, and mathematical formulas for the coefficient of variation, Pratt's measure, the Gini index, Theil's measure, and Atkinson's indices are explained. (14…
Rational Exponentials and Continued Fractions
ERIC Educational Resources Information Center
Denny, J. K.
2012-01-01
Using continued fraction expansions, we can approximate constants, such as pi and e, using an appropriate integer n raised to the power x[superscript 1/x], x a suitable rational. We review continued fractions and give an algorithm for producing these approximations.
NASA Astrophysics Data System (ADS)
Dias, Marcelo A.; Santangelo, Christian D.
2011-03-01
Despite an almost two thousand year history, origami, the art of folding paper, remains a challenge both artistically and scientifically. Traditionally, origami is practiced by folding along straight creases. A whole new set of shapes can be explored, however, if, instead of straight creases, one folds along arbitrary curves. We present a mechanical model for curved fold origami in which the energy of a plastically-deformed crease is balanced by the bending energy of developable regions on either side of the crease. Though geometry requires that a sheet buckle when folded along a closed curve, its shape depends on the elasticity of the sheet. NSF DMR-0846582.
NASA Technical Reports Server (NTRS)
Oliver, D. S.; Aldrich, R. E.; Krol, F. T.
1972-01-01
An electrically addressed liquid crystal Fourier plane filter capable of real time optical image processing is described. The filter consists of two parts: a wedge filter having forty 9 deg segments and a ring filter having twenty concentric rings in a one inch diameter active area. Transmission of the filter in the off (transparent) state exceeds fifty percent. By using polarizing optics, contrast as high as 10,000:1 can be achieved at voltages compatible with FET switching technology. A phenomenological model for the dynamic scattering is presented for this special case. The filter is designed to be operated from a computer and is addressed by a seven bit binary word which includes an on or off command and selects any one of the twenty rings or twenty wedge pairs. The overall system uses addressable latches so that once an element is in a specified state, it will remain there until a change of state command is received. The drive for the liquid crystal filter is ? 30 V peak at 30 Hz to 70 Hz. These parameters give a rise time for the scattering of 20 msec and a decay time of 80 to 100 msec.
ERIC Educational Resources Information Center
Muscat, Jean-Paul
1992-01-01
Uses LOGO to enhance the applicability of curve stitching in the mathematics curriculum. Presents the formulas and computer programs for the construction of parabolas, concentric circles, and epicycloids. Diagrams of constructed figures are provided. (MDH)
Crystallography on Curved Surfaces
NASA Astrophysics Data System (ADS)
Vitelli, Vincenzo; Lucks, Julius; Nelson, David
2007-03-01
We present a theoretical and numerical study of the static and dynamical properties that distinguish two dimensional curved crystals from their flat space counterparts. Experimental realizations include block copolymer mono-layers on lithographically patterned substrates and self-assembled colloidal particles on a curved interface. At the heart of our approach lies a simple observation: the packing of interacting spheres constrained to lie on a curved surface is necessarily frustrated even in the absence of defects. As a result, whenever lattice imperfections or topological defects are introduced in the curved crystal they couple to the pre-stress of geometric frustration giving rise to elastic potentials. These geometric potentials are non-local functions of the Gaussian curvature and depend on the position of the defects. They play an important role in stress relaxation dynamics, elastic instabilities and melting.
1984-11-01
the Mahalanobis distance defined in terms of t. In particular when 9 is diagonal the procedure amounts to finding the line that minimizes the weighted...the m~a~l of apj dimensional’ data set. They mhinima, the distance from the poinsa, and provide a mom-linear summary of the data. The carves awe moe...project there. The zmain theorems proms thaprincipal curves mre critical values of the expected squared distance between the points and the curve
Generators for the elliptic curve y2 = x3-nx
NASA Astrophysics Data System (ADS)
Fujita, Yasutsugu; Terai, Nobuhiro
2010-07-01
Let E:y2 = x3-nx be an elliptic curve over the rationals with a positive integer n. Mordell's theorem asserts that the group of rational points on E is finitely generated. Our interest is in the generators for its free part. Duquesne (2007) showed that if n = (2k2-2k+1)(18k2+30k+17) is square-free, then certain two points of infinite order can always be in a system of generators. We generalize this result and show that the same is true for "infinitely many" infinite families n = n(k,l) with two variables.
Highly curved microchannel plates
NASA Technical Reports Server (NTRS)
Siegmund, O. H. W.; Cully, S.; Warren, J.; Gaines, G. A.; Priedhorsky, W.; Bloch, J.
1990-01-01
Several spherically curved microchannel plate (MCP) stack configurations were studied as part of an ongoing astrophysical detector development program, and as part of the development of the ALEXIS satellite payload. MCP pairs with surface radii of curvature as small as 7 cm, and diameters up to 46 mm have been evaluated. The experiments show that the gain (greater than 1.5 x 10 exp 7) and background characteristics (about 0.5 events/sq cm per sec) of highly curved MCP stacks are in general equivalent to the performance achieved with flat MCP stacks of similar configuration. However, gain variations across the curved MCP's due to variations in the channel length to diameter ratio are observed. The overall pulse height distribution of a highly curved surface MCP stack (greater than 50 percent FWHM) is thus broader than its flat counterpart (less than 30 percent). Preconditioning of curved MCP stacks gives comparable results to flat MCP stacks, but it also decreases the overall gain variations. Flat fields of curved MCP stacks have the same general characteristics as flat MCP stacks.
Highly curved microchannel plates
NASA Technical Reports Server (NTRS)
Siegmund, O. H. W.; Cully, S.; Warren, J.; Gaines, G. A.; Priedhorsky, W.; Bloch, J.
1990-01-01
Several spherically curved microchannel plate (MCP) stack configurations were studied as part of an ongoing astrophysical detector development program, and as part of the development of the ALEXIS satellite payload. MCP pairs with surface radii of curvature as small as 7 cm, and diameters up to 46 mm have been evaluated. The experiments show that the gain (greater than 1.5 x 10 exp 7) and background characteristics (about 0.5 events/sq cm per sec) of highly curved MCP stacks are in general equivalent to the performance achieved with flat MCP stacks of similar configuration. However, gain variations across the curved MCP's due to variations in the channel length to diameter ratio are observed. The overall pulse height distribution of a highly curved surface MCP stack (greater than 50 percent FWHM) is thus broader than its flat counterpart (less than 30 percent). Preconditioning of curved MCP stacks gives comparable results to flat MCP stacks, but it also decreases the overall gain variations. Flat fields of curved MCP stacks have the same general characteristics as flat MCP stacks.
Rational approximations for tomographic reconstructions
NASA Astrophysics Data System (ADS)
Reynolds, Matthew; Beylkin, Gregory; Monzón, Lucas
2013-06-01
We use optimal rational approximations of projection data collected in x-ray tomography to improve image resolution. Under the assumption that the object of interest is described by functions with jump discontinuities, for each projection we construct its rational approximation with a small (near optimal) number of terms for a given accuracy threshold. This allows us to augment the measured data, i.e., double the number of available samples in each projection or, equivalently, extend (double) the domain of their Fourier transform. We also develop a new, fast, polar coordinate Fourier domain algorithm which uses our nonlinear approximation of projection data in a natural way. Using augmented projections of the Shepp-Logan phantom, we provide a comparison between the new algorithm and the standard filtered back-projection algorithm. We demonstrate that the reconstructed image has improved resolution without additional artifacts near sharp transitions in the image.
Psychology and the Rationality of Emotion*
Clore, Gerald L.
2014-01-01
Questions addressed by recent psychological research on emotion include questions about how thought shapes emotion and how emotion, in turn, shapes thought. Research on emotion and cognition paints a somewhat different picture than that seen in traditional discussions of passion and reason. This article reviews several aspects of this research, concentrating specifically on three views of rationality: Rationality as Process, Rationality as Product, and Rationality as Outcome. PMID:25125770
2008-12-01
regulated. After use, the product of the heating reaction is zinc oxide, an inert chemical used in many different products such as sunscreen , creams...low cost, easy-to-use chemical heater called the Flameless Ration Heater (FRH). The FRH consists of a magnesium/iron mixture sealed in a waterproof...Prescribed by ANSI Std Z39-18 2 1. HEATER DESIGN There is a narrow operating temperature range for chemical heaters for this specific
A Semantical Approach to Equilibria and Rationality
NASA Astrophysics Data System (ADS)
Pavlovic, Dusko
Game theoretic equilibria are mathematical expressions of rationality. Rational agents are used to model not only humans and their software representatives, but also organisms, populations, species and genes, interacting with each other and with the environment. Rational behaviors are achieved not only through conscious reasoning, but also through spontaneous stabilization at equilibrium points.
Rational Thinking in School-Based Practice
ERIC Educational Resources Information Center
Clark, Mary Kristen; Flynn, Perry
2011-01-01
Purpose: We reflect on Alan Kamhi's (2011) prologue on balancing certainty and uncertainty as it pertains to school-based practice. Method: In schools, rational thinking depends on effective team processes, much like professional learning communities. We consider the conditions that are required for rational thinking and how rational team dialogue…
Rationality and the Logic of Good Reasons.
ERIC Educational Resources Information Center
Fisher, Walter R.
This paper contends that the rationality of the logic of good reasons is constituted in its use. To support this claim, the paper presents an analysis of the relationship between being reasonable and being rational. It then considers how following the logic of good reasons leads to rationality in the behavior of individuals and groups; the latter…
2006-04-19
This view of the ringed planet shows its tilt relative to the plane of its orbit around the Sun. The planet tilts nearly 27 degrees relative to the ecliptic plane giving rise to seasons in which the rings shadow each hemisphere in its respective winter
NASA Astrophysics Data System (ADS)
Vassiliou, Peter J.
2009-10-01
Cartan's method of moving frames is briefly recalled in the context of immersed curves in the homogeneous space of a Lie group G. The contact geometry of curves in low dimensional equi-affine geometry is then made explicit. This delivers the complete set of invariant data which solves the G-equivalence problem via a straightforward procedure, and which is, in some sense a supplement to the equivariant method of Fels and Olver. Next, the contact geometry of curves in general Riemannian manifolds (M,g) is described. For the special case in which the isometries of (M,g) act transitively, it is shown that the contact geometry provides an explicit algorithmic construction of the differential invariants for curves in M. The inputs required for the construction consist only of the metric g and a parametrisation of structure group SO(n); the group action is not required and no integration is involved. To illustrate the algorithm we explicitly construct complete sets of differential invariants for curves in the Poincaré half-space H3 and in a family of constant curvature 3-metrics. It is conjectured that similar results are possible in other Cartan geometries.
Epitaxial growth, electrical and optical properties of a-plane InN on r-plane sapphire
Ajagunna, A. O.; Iliopoulos, E.; Tsiakatouras, G.; Tsagaraki, K.; Androulidaki, M.; Georgakilas, A.
2010-01-15
The heteroepitaxy of a-plane (1120) InN films on r-plane (1102) sapphire substrates, by nitrogen radio frequency plasma-assisted molecular beam epitaxy, has been investigated and compared to that of c-plane (0001) InN. The epitaxial growth of a-plane InN proceeded through the nucleation, growth, and coalescence of three-dimensional islands, resulting in surface roughness that increased monotonically with epilayer thickness. The full width at half maximum of (1120) x-ray diffraction rocking curves decreased significantly with increasing InN thickness, characteristic of structural improvement, and it reached the value of 24 arcmin for a 1 {mu}m thick film. Hall-effect measurements exhibited a similar dependence of electron concentration and mobility on thickness for both the a- and c-plane InN films. The analysis of the Hall-effect measurements, by considering the contribution of two conducting layers, indicates a similar accumulation of low mobility electrons with N{sub s}>10{sup 14} cm{sup -2} at the films' surface/interfacial region for both the a- and c-plane InN films. From optical transmittance measurements, the absorption edge of 0.768 eV was determined for the 1 {mu}m a-plane film, consistent with the expected Burstein-Moss effect. Photoluminescence spectra exhibited a lower energy peak at 0.631 eV, suggesting defect-related transitions.
The Milky Way rotation curve revisited
NASA Astrophysics Data System (ADS)
Russeil, D.; Zavagno, A.; Mège, P.; Poulin, Y.; Molinari, S.; Cambresy, L.
2017-05-01
The Herschel survey of the Galactic Plane (Hi-GAL) is a continuum Galactic plane survey in five wavebands at 70, 160, 250, 350 and 500 μm. From such images, about 150 000 sources have been extracted for which the distance determination is a challenge. In this context the velocity of these sources has been determined thanks to a large number of molecular data cubes. But to convert the velocity to kinematic distance, one needs to adopt a rotation curve for our Galaxy. For three different samples of tracers, we test different analytical forms. We find that the power-law expression, θ(R)/θ0 = 1.022 (R/R0)0.0803 with R0, θ0 = 8.34 kpc, 240 km s-1 is a good and easily manipulated expression for the distance determination process.
Leslie, Mark; Holloway, Charles A
2006-01-01
When a company launches a new product into a new market, the temptation is to immediately ramp up sales force capacity to gain customers as quickly as possible. But hiring a full sales force too early just causes the firm to burn through cash and fail to meet revenue expectations. Before it can sell an innovative product efficiently, the entire organization needs to learn how customers will acquire and use it, a process the authors call the sales learning curve. The concept of a learning curve is well understood in manufacturing. Employees transfer knowledge and experience back and forth between the production line and purchasing, manufacturing, engineering, planning, and operations. The sales learning curve unfolds similarly through the give-and-take between the company--marketing, sales, product support, and product development--and its customers. As customers adopt the product, the firm modifies both the offering and the processes associated with making and selling it. Progress along the manufacturing curve is measured by tracking cost per unit: The more a firm learns about the manufacturing process, the more efficient it becomes, and the lower the unit cost goes. Progress along the sales learning curve is measured in an analogous way: The more a company learns about the sales process, the more efficient it becomes at selling, and the higher the sales yield. As the sales yield increases, the sales learning process unfolds in three distinct phases--initiation, transition, and execution. Each phase requires a different size--and kind--of sales force and represents a different stage in a company's production, marketing, and sales strategies. Adjusting those strategies as the firm progresses along the sales learning curve allows managers to plan resource allocation more accurately, set appropriate expectations, avoid disastrous cash shortfalls, and reduce both the time and money required to turn a profit.
Escudero, Carlos
2009-08-15
Stochastic growth phenomena on curved interfaces are studied by means of stochastic partial differential equations. These are derived as counterparts of linear planar equations on a curved geometry after a reparametrization invariance principle has been applied. We examine differences and similarities with the classical planar equations. Some characteristic features are the loss of correlation through time and a particular behavior of the average fluctuations. Dependence on the metric is also explored. The diffusive model that propagates correlations ballistically in the planar situation is particularly interesting, as this propagation becomes nonuniversal in the new regime.
Arch length considerations due to the curve of Spee: a mathematical model.
Germane, N; Staggers, J A; Rubenstein, L; Revere, J T
1992-09-01
Arch length analysis should consider discrepancies not only within the sagittal plane but also within the vertical and transverse planes. The vertical deviation of the occlusal plane from a flat plane is known as the curve of Spee. The purpose of this study was to produce a mathematical model of the mandibular arch form in three planes of space and to determine the effect that the curve of Spee has on arch circumference. Two mandibular arch forms, the catenary and the Bonwill-Hawley, were examined. The curve of Spee was modeled as a cylinder perpendicular to the midsagittal plane centered on the arch anteroposteriorly. A mathematical distance formula was used to calculate arch circumferences from the central fossa of the first molars for 10 arches with curves of Spee ranging from 0 to 10 mm. This procedure was repeated for arch circumferences extending from the central fossa of the second molars. Plots for the difference in arch circumferences verses depth of the curve of Spee showed that the relationship between these two variables is not linear and is less than one to one. This model showed that clinical practice of allowing 1 mm of arch circumference for leveling each millimeter of curve of Spee overestimates the amount of arch circumference needed to flatten the curve of Spee.
Curve of Spee - from orthodontic perspective
Dhiman, Sushma
2015-01-01
The presence of a curve of Spee (COS) of variable depth is common finding in the occlusal arrangement and is sixth key of occlusion The understanding of COS in the field of orthodontics is very important as orthodontists deal with it in virtually every patient they treat. An excessive COS is a common form of malocclusion that may be addressed in many ways, including posterior extrusion, anterior intrusion, and incisor proclination. The specific approach to leveling of COS should be selected based on each patient's needs. Soft tissue, crown–gingival relations, occlusal plane, and skeletofacial concerns are among the special considerations for treatment planning for leveling of COS. PMID:26752075
Rational choice theory and suicide.
Lester, D
1988-12-01
The implications of viewing the decision to kill oneself as a rational choice, based on an analysis of the costs and benefits, were explored. Suicide is but one symptom for an individual in distress to choose, and if suicide is prevented, other symptoms may appear in its place. Similarly, a critical question to be asked in suicide prevention is whether restriction of the availability of one method for suicide (such as detoxifying domestic gas or car exhaust) will result in suicidal individuals switching to a different method for suicide or to a different symptom of distress.
A rational approach to dementia.
Ropper, A H
1979-01-01
Dementia is a common problem facing all medical practitioners and it frequently results in hospitalization and death. This review provides a framework for dealing with dementia in clinical practice that is based on both traditional concepts and recent advances in the understanding of the problem. Distinguishing at the bedside between dementia and other disorders of intellect is emphasized. The main causes of dementia and their clinical characteristics are reviewed and a rational approach to definitive diagnosis is developed. Simple, effective symptomatic forms of therapy are described. PMID:159118
The extended polar writhe: a tool for open curves mechanics
NASA Astrophysics Data System (ADS)
Prior, Christopher B.; Neukirch, Sébastien
2016-05-01
A measure of the writhing of a curve is introduced and is used to extend the Călugăreanu decomposition for closed curves, as well as the polar decomposition for curves bound between planes. The new writhe measure is also shown to be able to assess changes in linking due to belt-trick and knotting type deformations, and further its utility is illustrated on examples taken from elastic rod parameter-continuation studies. Finally C++ and mathematica codes are made available and shown to be faster than existing algorithms for the numerical computation of the writhe.
ERIC Educational Resources Information Center
Horton, Dawn M.
2001-01-01
This article reviews the history of the bell curve and its application to gifted education and suggests rejection of this paradigm in favor of a focus on criteria rather than norms and a better understanding of the distribution and structure of intelligence. (Contains references.) (DB)
ERIC Educational Resources Information Center
Bausell, R. Barker
1995-01-01
This editorial provides an informal review of "The Bell Curve" (Herrnstein and Murray, 1994). The book, packaged as scientific writing, is an attack on affirmative action and on government attempts to foster egalitarianism. It is a political treatise that assumes that racial differences in intelligence are valid and genetic. (SLD)
Textbook Factor Demand Curves.
ERIC Educational Resources Information Center
Davis, Joe C.
1994-01-01
Maintains that teachers and textbook graphics follow the same basic pattern in illustrating changes in demand curves when product prices increase. Asserts that the use of computer graphics will enable teachers to be more precise in their graphic presentation of price elasticity. (CFR)
ERIC Educational Resources Information Center
Harper, Suzanne R.; Driskell, Shannon
2005-01-01
Graphic tips for using the Geometer's Sketchpad (GSP) are described. The methods to import an image into GSP, define a coordinate system, plot points and curve fit the function using a graphical calculator are demonstrated where the graphic features of GSP allow teachers to expand the use of the technology application beyond the classroom.
ERIC Educational Resources Information Center
Harper, Suzanne R.; Driskell, Shannon
2005-01-01
Graphic tips for using the Geometer's Sketchpad (GSP) are described. The methods to import an image into GSP, define a coordinate system, plot points and curve fit the function using a graphical calculator are demonstrated where the graphic features of GSP allow teachers to expand the use of the technology application beyond the classroom.
Textbook Factor Demand Curves.
ERIC Educational Resources Information Center
Davis, Joe C.
1994-01-01
Maintains that teachers and textbook graphics follow the same basic pattern in illustrating changes in demand curves when product prices increase. Asserts that the use of computer graphics will enable teachers to be more precise in their graphic presentation of price elasticity. (CFR)
ERIC Educational Resources Information Center
Hunter, Walter M.
This document contains detailed directions for constructing a device that mechanically produces the three-dimensional shape resulting from the rotation of any algebraic line or curve around either axis on the coordinate plant. The device was developed in response to student difficulty in visualizing, and thus grasping the mathematical principles…
Straightening Out Learning Curves
ERIC Educational Resources Information Center
Corlett, E. N.; Morecombe, V. J.
1970-01-01
The basic mathematical theory behind learning curves is explained, together with implications for clerical and industrial training, evaluation of skill development, and prediction of future performance. Brief studies of textile worker and typist training are presented to illustrate such concepts as the reduction fraction (a consistent decrease in…
ERIC Educational Resources Information Center
Paulton, Richard J. L.
1991-01-01
A procedure that allows students to view an entire bacterial growth curve during a two- to three-hour student laboratory period is described. Observations of the lag phase, logarithmic phase, maximum stationary phase, and phase of decline are possible. A nonpathogenic, marine bacterium is used in the investigation. (KR)
Curved butterfly bileaflet prosthetic cardiac valve
McQueen, David M.; Peskin, Charles S.
1991-06-25
An annular valve body having a central passageway for the flow of blood therethrough with two curved leaflets each of which is pivotally supported on an accentric positioned axis in the central passageway for moving between a closed position and an open position. The leaflets are curved in a plane normal to the eccentric axis and positioned with the convex side of the leaflets facing each other when the leaflets are in the open position. Various parameters such as the curvature of the leaflets, the location of the eccentric axis, and the maximum opening angle of the leaflets are optimized according to the following performance criteria: maximize the minimum peak velocity through the valve, maximize the net stroke volume, and minimize the mean forward pressure difference, thereby reducing thrombosis and improving the hemodynamic performance.
Traffic noise and the hyperbolic plane
Gibbons, G.W. Warnick, C.M.
2010-04-15
We consider the problem of sound propagation in a wind. We note that the rays, as in the absence of a wind, are given by Fermat's principle and show how to map them to the trajectories of a charged particle moving in a magnetic field on a curved space. For the specific case of sound propagating in a stratified atmosphere with a small wind speed, we show that the corresponding particle moves in a constant magnetic field on the hyperbolic plane. In this way, we give a simple 'straightedge and compass' method to estimate the intensity of sound upwind and downwind. We construct Mach envelopes for moving sources. Finally, we relate the problem to that of finding null geodesics in a squashed anti-de Sitter spacetime and discuss the SO(3,1)xR symmetry of the problem from this point of view.
Design of large aperture focal plane shutter
NASA Astrophysics Data System (ADS)
Hu, Jia-wen; Ma, Wen-li; Huang, Jin-long
2012-09-01
To satisfy the requirement of large telescope, a large aperture focal plane shutter with aperture size of φ200mm was researched and designed to realize, which could be started and stopped in a relative short time with precise position, and also the blades could open and close at the same time at any orientation. Timing-belts and stepper motors were adopted as the drive mechanism. Velocity and position of the stepper motors were controlled by the PWM pulse generated by DSP. Exponential curve is applied to control the velocity of the stepper motors to make the shutter start and stop in a short time. The closing/open time of shutter is 0.2s, which meets the performance requirements of large telescope properly.
Sibling Curves 3: Imaginary Siblings and Tracing Complex Roots
ERIC Educational Resources Information Center
Harding, Ansie; Engelbrecht, Johann
2009-01-01
Visualizing complex roots of a quadratic equation has been a quest since the inception of the Argand plane in the 1800s. Many algebraic and numerical methods exist for calculating complex roots of an equation, but few visual methods exist. Following on from papers by Harding and Engelbrecht (A. Harding and J. Engelbrecht, "Sibling curves and…
Sibling Curves 3: Imaginary Siblings and Tracing Complex Roots
ERIC Educational Resources Information Center
Harding, Ansie; Engelbrecht, Johann
2009-01-01
Visualizing complex roots of a quadratic equation has been a quest since the inception of the Argand plane in the 1800s. Many algebraic and numerical methods exist for calculating complex roots of an equation, but few visual methods exist. Following on from papers by Harding and Engelbrecht (A. Harding and J. Engelbrecht, "Sibling curves and…
Use of the Zoom in the Analysis of a Curve.
ERIC Educational Resources Information Center
Montaner, F. Rubio
1987-01-01
How the computer can aid the teacher in discussing plane curves is shown. Use of the zoom enables the teacher to illustrate aspects of graphs that would be difficult and time-consuming to show in other ways. Many illustrative graphs are included, and four programs are listed. (MNS)
Rational error in internal medicine.
Federspil, Giovanni; Vettor, Roberto
2008-03-01
Epistemologists have selected two basic categories: that of errors committed in scientific research, when a researcher devises or accepts an unfounded hypothesis, and that of mistakes committed in the application of scientific knowledge whereby doctors rely on knowledge held to be true at the time in order to understand an individual patient's signs and symptoms. The paper will deal exclusively with the latter, that is to say the mistakes which physicians make while carrying out their day-to-day medical duties. The paper will deal with the mistakes committed in medicine trying also to offer a classification. It will take into account also examples of mistakes in Bayesian reasoning and mistakes of reasoning committed by clinicians regard inductive reasoning. Moreover, many other mistakes are due to fallacies of deductive logic, logic which they use on a day-to-day basis while examining patients in order to envisage the consequences of the various diagnostic or physiopathologic hypotheses. The existence of a different type of mistakes that are part of the psychology of thought will be also pointed out. We conclude that internists often make mistakes because, unknowingly, they fail to reason correctly. These mistakes can occur in two ways: either because he does not observe the laws of formal logic, or because his practical rationality does not match theoretical rationality and so his reasoning becomes influenced by the circumstances in which he finds himself.
Rational Prescription for a Dermatologist
Prakash, Bhanu; Nadig, Prathiba; Nayak, Amitha
2016-01-01
The ultimate goal in dermatological therapy is to use the safest and least number of drugs in order to obtain the best possible effect in the shortest period and at reasonable cost. Rational drug use (RDU) is conventionally defined as the use of an appropriate, efficacious, safe and cost-effective drug given for the right indications in the right dose and formulation, at right time intervals. WHO estimates that more than half of all medicines are prescribed, dispensed or sold inappropriately, and that half of all patients fail to take them correctly as prescribed by the doctor. The process of Rational prescription for a Dermatologist (RPD) involves a series of steps such as defining the patient's illness, specifying the treatment objectives, using the principle of P-treatment, starting the treatment, providing appropriate information and monitoring the treatment. Reasons for irrational prescription could be physician related, patient related, industry related, regulations related. Practicing medicine irrationally can lead to disastrous events like increased morbidity and mortality, drain of resources, drug resistance etc. Principles to enhance the RDU in our practice and minimize errors of prescription are discussed in detail in this article. PMID:26955092
Rational approximations to fluid properties
Kincaid, J.M.
1990-05-01
The purpose of this report is to summarize some results that were presented at the Spring AIChE meeting in Orlando, Florida (20 March 1990). We report on recent attempts to develop a systematic method, based on the technique of rational approximation, for creating mathematical models of real-fluid equations of state and related properties. Equation-of-state models for real fluids are usually created by selecting a function {tilde p} (T,{rho}) that contains a set of parameters {l brace}{gamma}{sub i}{r brace}; the {l brace}{gamma}{sub i}{r brace} is chosen such that {tilde p}(T,{rho}) provides a good fit to the experimental data. (Here p is the pressure, T the temperature and {rho} is the density). In most cases a nonlinear least-squares numerical method is used to determine {l brace}{gamma}{sub i}{r brace}. There are several drawbacks to this method: one has essentially to guess what {tilde p}(T,{rho}) should be; the critical region is seldom fit very well and nonlinear numerical methods are time consuming and sometimes not very stable. The rational approximation approach we describe may eliminate all of these drawbacks. In particular it lets the data choose the function {tilde p}(T,{rho}) and its numerical implementation involves only linear algorithms. 27 refs., 5 figs.
A new twist on the geometry of gravitational plane waves
NASA Astrophysics Data System (ADS)
Shore, Graham M.
2017-09-01
The geometry of twisted null geodesic congruences in gravitational plane wave spacetimes is explored, with special focus on homogeneous plane waves. The rôle of twist in the relation of the Rosen coordinates adapted to a null congruence with the fundamental Brinkmann coordinates is explained and a generalised form of the Rosen metric describing a gravitational plane wave is derived. The Killing vectors and isometry algebra of homogeneous plane waves (HPWs) are described in both Brinkmann and twisted Rosen form and used to demonstrate the coset space structure of HPWs. The van Vleck-Morette determinant for twisted congruences is evaluated in both Brinkmann and Rosen descriptions. The twisted null congruences of the Ozsváth-Schücking, `anti-Mach' plane wave are investigated in detail. These developments provide the necessary geometric toolkit for future investigations of the rôle of twist in loop effects in quantum field theory in curved spacetime, where gravitational plane waves arise generically as Penrose limits; in string theory, where they are important as string backgrounds; and potentially in the detection of gravitational waves in astronomy.
Pleats in crystals on curved surfaces.
Irvine, William T M; Vitelli, Vincenzo; Chaikin, Paul M
2010-12-16
Hexagons can easily tile a flat surface, but not a curved one. Introducing heptagons and pentagons (defects with topological charge) makes it easier to tile curved surfaces; for example, soccer balls based on the geodesic domes of Buckminster Fuller have exactly 12 pentagons (positive charges). Interacting particles that invariably form hexagonal crystals on a plane exhibit fascinating scarred defect patterns on a sphere. Here we show that, for more general curved surfaces, curvature may be relaxed by pleats: uncharged lines of dislocations (topological dipoles) that vanish on the surface and play the same role as fabric pleats. We experimentally investigate crystal order on surfaces with spatially varying positive and negative curvature. On cylindrical capillary bridges, stretched to produce negative curvature, we observe a sequence of transitions-consistent with our energetic calculations-from no defects to isolated dislocations, which subsequently proliferate and organize into pleats; finally, scars and isolated heptagons (previously unseen) appear. This fine control of crystal order with curvature will enable explorations of general theories of defects in curved spaces. From a practical viewpoint, it may be possible to engineer structures with curvature (such as waisted nanotubes and vaulted architecture) and to develop novel methods for soft lithography and directed self-assembly.
Seismological Constraints on Fault Plane Curvature
NASA Astrophysics Data System (ADS)
Reynolds, K.
2015-12-01
The down-dip geometry of seismically active normal faults is not well known. Many examples of normal faults with down-dip curvature exist, such as listric faults revealed in cross-section or in seismic reflection data, or the exposed domes of core complexes. However, it is not understood: (1) whether curved faults fail in earthquakes, and (2) if those faults have generated earthquakes, is the curvature a primary feature of the rupture or due to later modification of the plane? Even if an event is surface-rupturing, because of the limited depth-extent over which observations can be made, it is difficult to reliably constrain the change in dip with depth (if any) and therefore the fault curvature. Despite the uncertainty in seismogenic normal fault geometries, published slip inversions most commonly use planar fault models. We investigate the seismological constraints on normal fault geometry using a forward-modelling approach and present a seismological technique for determining down-dip geometry. We demonstrate that complexity in the shape of teleseismic body waveforms may be used to investigate the presence of down-dip fault plane curvature. We have applied this method to a catalogue of continental and oceanic normal faulting events. Synthetic models demonstrate that the shapes of SH waveforms at along-strike stations are particularly sensitive to fault plane geometry. It is therefore important to consider the azimuthal station coverage before modelling an event. We find that none of the data require significant down-dip curvature, although the modelling results for some events remain ambiguous. In some cases we can constrain that the down-dip fault geometry is within 20° of planar.
Plane reconstruction ultrasound tomography device
Hassler, D.
1984-10-23
An ultrasound tomography device for scanning an object under examination from a plurality of directions. Coronal slice images of the plane areas near or at the female breast wall are obtained. Ultrasound lobes from ultrasound transducers are electronically directed or mechanically positioned to obliquely strike the coronal slice located at or near the breast wall. A full image of the coronal slice plane is reconstructed through section by section combination of the images obtained from the several ultrasound lobes.
Interactive visualizations of blowups of the plane.
Schenzel, Peter; Stussak, Christian
2013-06-01
Blowups are an important technique in algebraic geometry that permit the smoothing of singular algebraic varieties. It is a challenge to visualize this process even in the case of blowups of points X in the affine plane AA(IR)(2). First results were obtained by Brodmann with the aid of the so-called toroidal blowup, a compact embedding of the blowup into affine 3-space. In fact, Brodmann provides a rational parametrization of the toroidal blowup, but its visualization fails in the neighborhood of X because the parametrization tends to indefinite terms of the form 0/0. Our approach is based on implicitization of the parametric form. By methods from commutative algebra we are able to reduce the implicitization to the computation of a single, fairly simple resultant. This provides an algebraic equation of the implicit surface of the toroidal blowup including the so-called exceptional fiber associated with X. Surprisingly, the degree of the equation grows only linearly with the degree of the parametrization. By applying additional clipping techniques to the implicit surface we are able to visualize the toroidal blowup as well as its deformations by several parameters interactively in real time using GPU-based ray casting techniques. The methods of the paper provide insights in the structure of blowups of points, even if the points are interactively moved or tend to degenerations.
Modeling magnetization curves in magnetic thin films with striped patterns.
Martínez, M Di Pietro; Milano, J; Eddrief, M; Marangolo, M; Bustingorry, S
2016-04-06
In this work, we study magnetic thin films presenting magnetic stripe patterns. A fingerprint of such domains is a linear behavior of the in-plane magnetization curves below a given saturation field. We present free energy models for the in-plane magnetization curves which permit us to extract key geometrical information about the stripe patterns, such as the maximum canted angle of the magnetization and the domain wall width. As an example, we discuss in this work magnetization curves for Fe(1-x)Ga(x) magnetic films which present a stripe pattern with a period of 160 nm and we found a typical maximum canted angle of 85° and a domain wall width around 30 nm.
Modeling magnetization curves in magnetic thin films with striped patterns
NASA Astrophysics Data System (ADS)
Di Pietro Martínez, M.; Milano, J.; Eddrief, M.; Marangolo, M.; Bustingorry, S.
2016-04-01
In this work, we study magnetic thin films presenting magnetic stripe patterns. A fingerprint of such domains is a linear behavior of the in-plane magnetization curves below a given saturation field. We present free energy models for the in-plane magnetization curves which permit us to extract key geometrical information about the stripe patterns, such as the maximum canted angle of the magnetization and the domain wall width. As an example, we discuss in this work magnetization curves for Fe1-x Ga x magnetic films which present a stripe pattern with a period of 160 nm and we found a typical maximum canted angle of {{85}{^\\circ}} and a domain wall width around 30 nm.
Determining the pivotal plane of fluid lipid membranes in simulations
NASA Astrophysics Data System (ADS)
Wang, Xin; Deserno, Markus
2015-10-01
Each leaflet of a curved lipid membrane contains a surface at which the area strain vanishes, the so-called pivotal plane. Its distance z0 from the bilayer's midplane arises in numerous contexts, for instance the connection between monolayer and bilayer moduli, stress-profile moments, or area-difference elasticity theories. Here, we propose two precise methods for determining the location of the pivotal plane in computer simulations, both of which rely on monitoring the lipid imbalance across a curved bilayer. The first method considers the ratio of lipid number between the two leaflets of cylindrical or spherical vesicles; it hence requires lipid flip-flop for equilibration. The second method looks at the leaflet difference across local sections cut out from a buckled membrane; this observable equilibrates even in the absence of flip-flop. We apply our methods to two different coarse-grained lipid models, the generic three-bead solvent-free Cooke model and a ten-bead representation of dimyristoylphosphocholine with the explicit solvent MARTINI model. The Cooke model is amenable to both methods and gives results that agree at the percent level. Using it, we also show that the pivotal plane moves outward as lipid curvature becomes more positive. The MARTINI model can only be analyzed with the buckling method; the obtained value z0 = 0.850(11) nm lies about 0.4 nm inwards of the glycerol backbone and is hence unexpectedly small. We attribute this to limitations of the coarse-grained description, suggesting that the location of the pivotal plane might be a good indicator for how well lipid models capture the microscopic origins of curvature elasticity. Finally, we also show that the pivotal plane position itself moves as the membrane is bent. The leading correction is linear in curvature, dependent on the Poisson ratio, and can matter when analyzing experimental results obtained from highly curved inverse hexagonal phases.
Boyer, H.E.
1986-01-01
This Atlas was developed to serve engineers who are looking for fatigue data on a particular metal or alloy. Having these curves compiled in a single book will also facilitate the computerization of the involved data. It is pointed out that plans are under way to make the data in this book available in ASCII files for analysis by computer programs. S-N curves which typify effects of major variables are considered along with low-carbon steels, medium-carbon steels, alloy steels, HSLA steels, high-strength alloy steels, heat-resisting steels, stainless steels, maraging steels, cast irons, and heat-resisting alloys. Attention is also given to aluminum alloys, copper alloys, magnesium alloys, molybdenum, tin alloys, titanium and titanium alloys, zirconium, steel castings, closed-die forgings, powder metallurgy parts, composites, effects of surface treatments, and test results for component parts.
NASA Astrophysics Data System (ADS)
Brandenburg, J. P.
2013-08-01
Fault-propagation folds form an important trapping element in both onshore and offshore fold-thrust belts, and as such benefit from reliable interpretation. Building an accurate geologic interpretation of such structures requires palinspastic restorations, which are made more challenging by the interplay between folding and faulting. Trishear (Erslev, 1991; Allmendinger, 1998) is a useful tool to unravel this relationship kinematically, but is limited by a restriction to planar fault geometries, or at least planar fault segments. Here, new methods are presented for trishear along continuously curved reverse faults defining a flat-ramp transition. In these methods, rotation of the hanging wall above a curved fault is coupled to translation along a horizontal detachment. Including hanging wall rotation allows for investigation of structures with progressive backlimb rotation. Application of the new algorithms are shown for two fault-propagation fold structures: the Turner Valley Anticline in Southwestern Alberta, and the Alpha Structure in the Niger Delta.
NASA Astrophysics Data System (ADS)
Vo, Martin
2017-08-01
Light Curves Classifier uses data mining and machine learning to obtain and classify desired objects. This task can be accomplished by attributes of light curves or any time series, including shapes, histograms, or variograms, or by other available information about the inspected objects, such as color indices, temperatures, and abundances. After specifying features which describe the objects to be searched, the software trains on a given training sample, and can then be used for unsupervised clustering for visualizing the natural separation of the sample. The package can be also used for automatic tuning parameters of used methods (for example, number of hidden neurons or binning ratio). Trained classifiers can be used for filtering outputs from astronomical databases or data stored locally. The Light Curve Classifier can also be used for simple downloading of light curves and all available information of queried stars. It natively can connect to OgleII, OgleIII, ASAS, CoRoT, Kepler, Catalina and MACHO, and new connectors or descriptors can be implemented. In addition to direct usage of the package and command line UI, the program can be used through a web interface. Users can create jobs for ”training” methods on given objects, querying databases and filtering outputs by trained filters. Preimplemented descriptors, classifier and connectors can be picked by simple clicks and their parameters can be tuned by giving ranges of these values. All combinations are then calculated and the best one is used for creating the filter. Natural separation of the data can be visualized by unsupervised clustering.
Schulz, Douglas A.
2007-10-08
A biometric system suitable for validating user identity using only mouse movements and no specialized equipment is presented. Mouse curves (mouse movements with little or no pause between them) are individually classied and used to develop classication histograms, which are representative of an individual's typical mouse use. These classication histograms can then be compared to validate identity. This classication approach is suitable for providing continuous identity validation during an entire user session.
Kepler Mission's focal plane characterization models implementation
NASA Astrophysics Data System (ADS)
Allen, Christopher; Klaus, Todd; Jenkins, Jon
2010-07-01
The Kepler Mission photometer is an unusually complex array of CCDs. A large number of time-varying instrumental and systematic effects must be modeled and removed from the Kepler pixel data to produce light curves of sufficiently high quality for the mission to be successful in its planet-finding objective. After the launch of the spacecraft, many of these effects are difficult to remeasure frequently, and various interpolations over a small number of sample measurements must be used to determine the correct value of a given effect at different points in time. A library of software modules, called Focal Plane Characterization (FC) Models, is the element of the Kepler Science Data Pipeline (hereafter "pipeline") that handles this. FC, or products generated by FC, are used by nearly every element of the SOC processing chain. FC includes Java components: database persistence classes, operations classes, model classes, and data importers; and MATLAB code: model classes, interpolation methods, and wrapper functions. These classes, their interactions, and the database tables they represent, are discussed. This paper describes how these data and the FC software work together to provide the pipeline with the correct values to remove non-photometric effects caused by the photometer and its electronics from the Kepler light curves. The interpolation mathematics is reviewed, as well as the special case of the sky-to-pixel/pixel-to-sky coordinate transformation code, which incorporates a compound model that is unique in the SOC software.
Laboratory Evaluation of Australian Ration Packs.
1982-09-01
thiamin, ascorbic acid and energy of rations are included. Daily available nutrients are estimated and evaluated with respect of daily requirement...of rations are included. Daily available nutrients are estimated and evaluated with respect to daily requirements. Some rations were found to be...at the AFFSE were also examined for microbiological quality. TABLE 1 Energy per Gram of Nutrient NUTRIENT kJ/g Protein 17 Fat 37 Carbohydrate 16
A Study of the Gamma-Ray Burst Fundamental Plane
NASA Astrophysics Data System (ADS)
Dainotti, Maria; Hernandez, Xavier; Postnikov, Sergey; Nagataki, Shigehiro; O'Brien, P. T.; Willingale, Richard; Striegel, Stephanie
2017-08-01
Long gamma-ray bursts (GRBs) with a plateau phase in their X-ray afterglows obeys a three-dimensional (3D) relation (Dainotti et al. 2016), between the rest-frame time at the end of the plateau, Ta, its corresponding X-ray luminosity, La, and the peak luminosity in the prompt emission, Lpeak, an extension of the two-dimensional Dainotti relation. This 3D relation identifies a GRB fundamental plane whose existence we here confirm. We extend the original analysis with X-ray data untill July 2016 gathering 183 Swift GRBs with afterglow plateaus and known redshifts. We compare several GRB categories, such as shorts with extended emission, SEE, X-ray Flashes, GRBs associated with SNe, 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. The relation planes for each of these categories are not statistically different from the gold fundamental plane, with the exception of the SEE, which are hence identified as a physically distinct class of objects. 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. Additionally, we tested this 3D relations by using GRBs observed at high energy, namely the peak luminosity values derived by the Fermi-Gamma Ray Burst Monitor (GBM). The 3D relation is also confirmed for GRBs observed by the GBM, thus showing its independence from the energy range. Furthermore, 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.
High speed curved position sensitive detector
Hendricks, Robert W.; Wilson, Jack W.
1989-01-01
A high speed curved position sensitive porportional counter detector for use in x-ray diffraction, the detection of 5-20 keV photons and the like. The detector employs a planar anode assembly of a plurality of parallel metallic wires. This anode assembly is supported between two cathode planes, with at least one of these cathode planes having a serpentine resistive path in the form of a meander having legs generally perpendicular to the anode wires. This meander is produced by special microelectronic fabrication techniques whereby the meander "wire" fans outwardly at the cathode ends to produce the curved aspect of the detector, and the legs of the meander are small in cross-section and very closely spaced whereby a spatial resolution of about 50 .mu.m can be achieved. All of the other performance characteristics are about as good or better than conventional position sensitive proportional counter type detectors. Count rates of up to 40,000 counts per second with 0.5 .mu.s shaping time constants are achieved.
Dual Rationality and Deliberative Agents
NASA Astrophysics Data System (ADS)
Debenham, John; Sierra, Carles
Human agents deliberate using models based on reason for only a minute proportion of the decisions that they make. In stark contrast, the deliberation of artificial agents is heavily dominated by formal models based on reason such as game theory, decision theory and logic—despite that fact that formal reasoning will not necessarily lead to superior real-world decisions. Further the Nobel Laureate Friedrich Hayek warns us of the ‘fatal conceit’ in controlling deliberative systems using models based on reason as the particular model chosen will then shape the system’s future and either impede, or eventually destroy, the subtle evolutionary processes that are an integral part of human systems and institutions, and are crucial to their evolution and long-term survival. We describe an architecture for artificial agents that is founded on Hayek’s two rationalities and supports the two forms of deliberation used by mankind.
Decision making: rational or hedonic?
Cabanac, Michel; Bonniot-Cabanac, Marie-Claude
2007-01-01
Three experiments studied the hedonicity of decision making. Participants rated their pleasure/displeasure while reading item-sentences describing political and social problems followed by different decisions (Questionnaire 1). Questionnaire 2 was multiple-choice, grouping the items from Questionnaire 1. In Experiment 1, participants answered Questionnaire 2 rapidly or slowly. Both groups selected what they had rated as pleasant, but the 'leisurely' group maximized pleasure less. In Experiment 2, participants selected the most rational responses. The selected behaviors were pleasant but less than spontaneous behaviors. In Experiment 3, Questionnaire 2 was presented once with items grouped by theme, and once with items shuffled. Participants maximized the pleasure of their decisions, but the items selected on Questionnaires 2 were different when presented in different order. All groups maximized pleasure equally in their decisions. These results support that decisions are made predominantly in the hedonic dimension of consciousness. PMID:17848195
Scottish psychoanalysis: a rational religion.
Miller, Gavin
2008-01-01
The ambition to rationally preserve a Christian religious inheritance distinctively informs Scottish psychoanalytic ideas. Scottish psychoanalysis presents the human personality as born into communion with others. The aim of therapy is to restore, preserve, and promote genuinely interpersonal relations. The Scottish psychoanalysis apparent in the work of W. R. D. Fairbairn, Ian Suttie, Hugh Crichton-Miller, and in the philosophy of John Macmurray, is exported to New Zealand, where it is promoted by the New Zealand Association of Psychotherapists. Scottish psychoanalytic ideas also remain effective in post-war Britain: the idea of communion appears in dialogue with other theories in the work of Harry Guntrip, John Macquarrie, R. D. Laing, and Aaron Esterson.
Navigating solid medical images by pencils of sectioning planes
NASA Astrophysics Data System (ADS)
Bookstein, Fred L.; Athey, Brian D.; Green, William D. K.; Wetzel, Arthur W.
2000-10-01
Beyond their involvement in ordinary surface rendering, the boundaries of organs in medical images have differential properties that make them quite useful for quantitative understanding. In particular, their geometry affords a framework for navigating the original solid, representing its R3 contents quite flexibility as multiple pseudovolumes R2 x T, where T is ar eal-valued parameter standing for screen time. A navigation is a smoothly parameterized series of image sections characterized by normal direction, centerpoint, scale and orientation. Such filmstrips represent a radical generalization of conventional medical image dynamics. The lances encountered in these navigations can be represented by constructs from classic differential geometry. Sequences of plane sections can be formalized as continuous pencils of planes, sets of cardinality (infinity) 1 that are sometimes explicitly characterized by a real-value parameter and sometimes defined implicitly as the intersection (curve of common elements) of a pair of bundles of (infinity) 2 planes. An example of the first type of navigation is the pencil of planes through the tangent line at one point of a curve; of the second type, the cone of planes through a point tangent to a surface. The further enhancements of centering, orienting, and rescaling in the medical context are intended to leave landmark points or boundary intersections invariant on the screen. Edgewarp, a publicly available software package, allows free play with pencils of planes like these as they section one single enormous medical data resource, the Visible Human data sets from the National Library of Medicine. This paper argues the relative merits of such visualizations over conventional surface-rendered flybys for understanding and communication of associated anatomical knowledge.
From rational bubbles to crashes
NASA Astrophysics Data System (ADS)
Sornette, D.; Malevergne, Y.
2001-10-01
We study and generalize in various ways the model of rational expectation (RE) bubbles introduced by Blanchard and Watson in the economic literature. Bubbles are argued to be the equivalent of Goldstone modes of the fundamental rational pricing equation, associated with the symmetry-breaking introduced by non-vanishing dividends. Generalizing bubbles in terms of multiplicative stochastic maps, we summarize the result of Lux and Sornette that the no-arbitrage condition imposes that the tail of the return distribution is hyperbolic with an exponent μ<1. We then outline the main results of Malevergne and Sornette, who extend the RE bubble model to arbitrary dimensions d: a number d of market time series are made linearly interdependent via d× d stochastic coupling coefficients. We derive the no-arbitrage condition in this context and, with the renewal theory for products of random matrices applied to stochastic recurrence equations, we extend the theorem of Lux and Sornette to demonstrate that the tails of the unconditional distributions associated with such d-dimensional bubble processes follow power laws, with the same asymptotic tail exponent μ<1 for all assets. The distribution of price differences and of returns is dominated by the same power-law over an extended range of large returns. Although power-law tails are a pervasive feature of empirical data, the numerical value μ<1 is in disagreement with the usual empirical estimates μ≈3. We then discuss two extensions (the crash hazard rate model and the non-stationary growth rate model) of the RE bubble model that provide two ways of reconciliation with the stylized facts of financial data.
ERIC Educational Resources Information Center
Kalberg, Stephen
1980-01-01
Explores rationality in Max Weber's works and identifies four types of rationality which play major roles in his writing--practical, theoretical, substantive, and formal. Implications for society and education are discussed. (DB)
ERIC Educational Resources Information Center
Kalberg, Stephen
1980-01-01
Explores rationality in Max Weber's works and identifies four types of rationality which play major roles in his writing--practical, theoretical, substantive, and formal. Implications for society and education are discussed. (DB)
Curved PVDF airborne transducer.
Wang, H; Toda, M
1999-01-01
In the application of airborne ultrasonic ranging measurement, a partially cylindrical (curved) PVDF transducer can effectively couple ultrasound into the air and generate strong sound pressure. Because of its geometrical features, the ultrasound beam angles of a curved PVDF transducer can be unsymmetrical (i.e., broad horizontally and narrow vertically). This feature is desired in some applications. In this work, a curved PVDF air transducer is investigated both theoretically and experimentally. Two resonances were observed in this transducer. They are length extensional mode and flexural bending mode. Surface vibration profiles of these two modes were measured by a laser vibrometer. It was found from the experiment that the surface vibration was not uniform along the curvature direction for both vibration modes. Theoretical calculations based on a model developed in this work confirmed the experimental results. Two displacement peaks were found in the piezoelectric active direction of PVDF film for the length extensional mode; three peaks were found for the flexural bending mode. The observed peak positions were in good agreement with the calculation results. Transient surface displacement measurements revealed that vibration peaks were in phase for the length extensional mode and out of phase for the flexural bending mode. Therefore, the length extensional mode can generate a stronger ultrasound wave than the flexural bending mode. The resonance frequencies and vibration amplitudes of the two modes strongly depend on the structure parameters as well as the material properties. For the transducer design, the theoretical model developed in this work can be used to optimize the ultrasound performance.
Magnetism in curved geometries
Streubel, Robert; Fischer, Peter; Kronast, Florian; ...
2016-08-17
Extending planar two-dimensional structures into the three-dimensional space has become a general trend in multiple disciplines, including electronics, photonics, plasmonics and magnetics. This approach provides means to modify conventional or to launch novel functionalities by tailoring the geometry of an object, e.g. its local curvature. In a generic electronic system, curvature results in the appearance of scalar and vector geometric potentials inducing anisotropic and chiral effects. In the specific case of magnetism, even in the simplest case of a curved anisotropic Heisenberg magnet, the curvilinear geometry manifests two exchange-driven interactions, namely effective anisotropy and antisymmetric exchange, i.e. Dzyaloshinskii–Moriya-like interaction. Asmore » a consequence, a family of novel curvature-driven effects emerges, which includes magnetochiral effects and topologically induced magnetization patterning, resulting in theoretically predicted unlimited domain wall velocities, chirality symmetry breaking and Cherenkov-like effects for magnons. The broad range of altered physical properties makes these curved architectures appealing in view of fundamental research on e.g. skyrmionic systems, magnonic crystals or exotic spin configurations. In addition to these rich physics, the application potential of three-dimensionally shaped objects is currently being explored as magnetic field sensorics for magnetofluidic applications, spin-wave filters, advanced magneto-encephalography devices for diagnosis of epilepsy or for energy-efficient racetrack memory devices. Finally, these recent developments ranging from theoretical predictions over fabrication of three-dimensionally curved magnetic thin films, hollow cylinders or wires, to their characterization using integral means as well as the development of advanced tomography approaches are in the focus of this review.« less
Magnetism in curved geometries
Streubel, Robert; Fischer, Peter; Kronast, Florian; Kravchuk, Volodymyr P.; Sheka, Denis D.; Gaididei, Yuri; Schmidt, Oliver G.; Makarov, Denys
2016-08-17
Extending planar two-dimensional structures into the three-dimensional space has become a general trend in multiple disciplines, including electronics, photonics, plasmonics and magnetics. This approach provides means to modify conventional or to launch novel functionalities by tailoring the geometry of an object, e.g. its local curvature. In a generic electronic system, curvature results in the appearance of scalar and vector geometric potentials inducing anisotropic and chiral effects. In the specific case of magnetism, even in the simplest case of a curved anisotropic Heisenberg magnet, the curvilinear geometry manifests two exchange-driven interactions, namely effective anisotropy and antisymmetric exchange, i.e. Dzyaloshinskii–Moriya-like interaction. As a consequence, a family of novel curvature-driven effects emerges, which includes magnetochiral effects and topologically induced magnetization patterning, resulting in theoretically predicted unlimited domain wall velocities, chirality symmetry breaking and Cherenkov-like effects for magnons. The broad range of altered physical properties makes these curved architectures appealing in view of fundamental research on e.g. skyrmionic systems, magnonic crystals or exotic spin configurations. In addition to these rich physics, the application potential of three-dimensionally shaped objects is currently being explored as magnetic field sensorics for magnetofluidic applications, spin-wave filters, advanced magneto-encephalography devices for diagnosis of epilepsy or for energy-efficient racetrack memory devices. Finally, these recent developments ranging from theoretical predictions over fabrication of three-dimensionally curved magnetic thin films, hollow cylinders or wires, to their characterization using integral means as well as the development of advanced tomography approaches are in the focus of this review.
Magnetism in curved geometries
NASA Astrophysics Data System (ADS)
Streubel, Robert; Fischer, Peter; Kronast, Florian; Kravchuk, Volodymyr P.; Sheka, Denis D.; Gaididei, Yuri; Schmidt, Oliver G.; Makarov, Denys
2016-09-01
Extending planar two-dimensional structures into the three-dimensional space has become a general trend in multiple disciplines, including electronics, photonics, plasmonics and magnetics. This approach provides means to modify conventional or to launch novel functionalities by tailoring the geometry of an object, e.g. its local curvature. In a generic electronic system, curvature results in the appearance of scalar and vector geometric potentials inducing anisotropic and chiral effects. In the specific case of magnetism, even in the simplest case of a curved anisotropic Heisenberg magnet, the curvilinear geometry manifests two exchange-driven interactions, namely effective anisotropy and antisymmetric exchange, i.e. Dzyaloshinskii-Moriya-like interaction. As a consequence, a family of novel curvature-driven effects emerges, which includes magnetochiral effects and topologically induced magnetization patterning, resulting in theoretically predicted unlimited domain wall velocities, chirality symmetry breaking and Cherenkov-like effects for magnons. The broad range of altered physical properties makes these curved architectures appealing in view of fundamental research on e.g. skyrmionic systems, magnonic crystals or exotic spin configurations. In addition to these rich physics, the application potential of three-dimensionally shaped objects is currently being explored as magnetic field sensorics for magnetofluidic applications, spin-wave filters, advanced magneto-encephalography devices for diagnosis of epilepsy or for energy-efficient racetrack memory devices. These recent developments ranging from theoretical predictions over fabrication of three-dimensionally curved magnetic thin films, hollow cylinders or wires, to their characterization using integral means as well as the development of advanced tomography approaches are in the focus of this review.
NASA Astrophysics Data System (ADS)
Kalnajs, Agris J.
One can obtain a fairly good understanding of the relation between axially symmetric mass distributions and the rotation curves they produce without resorting to calculations. However it does require a break with tradition. The first step consists of replacing quantities such as surface density, volume density, and circular velocity with the mass in a ring, mass in a spherical shell, and the square of the circular velocity, or more precisely with 2 pi G r mu(r), 4 pi G r^2 rho(r), and Vc^2 (r). These three quantities all have the same dimensions, and are related to each other by scale-free linear operators. The second step consists of introducing ln(r) as the coordinate. On the log scale the scale-free operators becomes the more familiar convolution operations. Convolutions are easily handled by Fourier techniques and a surface density can be converted into a rotation curve or volume density in a small fraction of a second. A simple plot of 2 pi G r mu(r) as a function of ln(r) reveals the relative contributions of different radii to Vc^2(r). Such a plot also constitutes a sanity test for the fitting of various laws to photometric data. There are numerous examples in the literature of excellent fits to the tails that lack data or are poor fits around the maximum of 2 pi G r mu(r). I will discuss some exact relations between the above three quantities as well as some empirical observations such as the near equality of the maxima of 2 pi G r mu(r) and Vc^2 (r) curves for flat mass distributions.
The Laplace Planes of Uranus and Pluto
NASA Technical Reports Server (NTRS)
Dobrovolskis, Anthony R.
1993-01-01
Satellite orbits close to an oblate planet precess about its equatorial plane, while distant satellites precess around the plane of the planet's heliocentric orbit. In between, satellites in nearly circular orbits precess about a warped intermediate surface called the Laplace 'plane.' Herein we derive general formulas for locating the Laplace plane. Because Uranus and Pluto have high obliquities, their Laplace planes are severely warped. We present maps of these Laplace planes, of interest in telescopic searches for new satellites. The Laplace plane of the Solar System as a whole is similarly distorted, but comets in the inner Oort cloud precess too slowly to sense the Laplace plane.
Complementary Curves of Descent
2012-11-16
provision of law , no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid...curves of descent 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT...NUMBER 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) US Naval Academy,Physics Department,Annapolis,MD,21402-1363 8. PERFORMING ORGANIZATION
NASA Astrophysics Data System (ADS)
Forgács, Péter; Lukács, Árpád; Romańczukiewicz, Tomasz
2013-12-01
It is shown that in a large class of systems, plane waves act as tractor beams: i.e., an incident plane wave can exert a pulling force on the scatterer. The underlying physical mechanism for the pulling force is due to the sufficiently strong scattering of the incoming wave into another mode carrying more momentum, in which case excess momentum is created behind the scatterer. This tractor beam or negative radiation pressure (NRP) effect, is found to be generic in systems with multiple scattering channels. In a birefringent medium, electromagnetic plane waves incident on a thin plate exert NRP of the same order of magnitude as optical radiation pressure, while in artificial dielectrics (metamaterials), the magnitude of NRP can even be macroscopic. In two dimensions, we study various scattering situations on vortices, and NRP is shown to occur by the scattering of heavy baryons into light leptons off cosmic strings, and by neutron scattering off vortices in the XY model.
Marsh, S.P.
1988-03-08
An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 4 figs.
Marsh, Stanley P.
1988-01-01
An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive.
Marsh, S.P.
1987-03-12
An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 3 figs., 3 tabs.
The Rationality of Alcoholics Anonymous and the Spirituality of Rational Emotive Behavior Therapy.
ERIC Educational Resources Information Center
Velten, Emmett
1996-01-01
Argues that Alcoholics Anonymous (AA) and Rational Emotive Behavior Therapy (REBT) share important rational objectives and numerous cognitive-behavioral methods. Both emphasize a philosophical shift as a principal ingredient for change. Provides definitions of rationality and spirituality and explains how REBT and smart recovery are spiritual…
The Rationality of Alcoholics Anonymous and the Spirituality of Rational Emotive Behavior Therapy.
ERIC Educational Resources Information Center
Velten, Emmett
1996-01-01
Argues that Alcoholics Anonymous (AA) and Rational Emotive Behavior Therapy (REBT) share important rational objectives and numerous cognitive-behavioral methods. Both emphasize a philosophical shift as a principal ingredient for change. Provides definitions of rationality and spirituality and explains how REBT and smart recovery are spiritual…
Space-Plane Spreadsheet Program
NASA Technical Reports Server (NTRS)
Mackall, Dale
1993-01-01
Basic Hypersonic Data and Equations (HYPERDATA) spreadsheet computer program provides data gained from three analyses of performance of space plane. Equations used to perform analyses derived from Newton's second law of physics, derivation included. First analysis is parametric study of some basic factors affecting ability of space plane to reach orbit. Second includes calculation of thickness of spherical fuel tank. Third produces ratio between volume of fuel and total mass for each of various aircraft. HYPERDATA intended for use on Macintosh(R) series computers running Microsoft Excel 3.0.
Space-Plane Spreadsheet Program
NASA Technical Reports Server (NTRS)
Mackall, Dale
1993-01-01
Basic Hypersonic Data and Equations (HYPERDATA) spreadsheet computer program provides data gained from three analyses of performance of space plane. Equations used to perform analyses derived from Newton's second law of physics, derivation included. First analysis is parametric study of some basic factors affecting ability of space plane to reach orbit. Second includes calculation of thickness of spherical fuel tank. Third produces ratio between volume of fuel and total mass for each of various aircraft. HYPERDATA intended for use on Macintosh(R) series computers running Microsoft Excel 3.0.
When Is a Bernstein-bezier Curve the Graph of a Function?
NASA Technical Reports Server (NTRS)
Mclaughlin, H. W.
1985-01-01
The question of determining when a Bernstein-Bezier cubic curve in the plane can be represented as the graph of function in some fixed orthogonal coordinate system is considered. The notion of a curve being monotone in a given direction is introduced to aid in the analysis.
GaAlAs gain-guided semiconductor lasers with a curved facet
Yamashita, S.; Nakatsuka, S.; Tanaka, T.; Ono, Y.; Chinone, N.; Kajimura, T.
1987-11-23
GaAlAs gain-guided semiconductor lasers having a curved facet are fabricated by employing reactive ion beam etching. The use of the curved facet permits stabilization of transverse mode in the direction parallel to the junction plane, reduction of astigmatism, and multilongitudinal mode oscillation.
Regular Polygons with Rational Area or Perimeter.
ERIC Educational Resources Information Center
Killgrove, R. B.; Koster, D. W.
1991-01-01
Discussed are two approaches to determining which regular polygons, either inscribed within or circumscribed about the unit circle, exhibit rational area or rational perimeter. One approach involves applications of abstract theory from a typical modern algebra course, whereas the other approach employs material from a traditional…
The Emotional and Moral Basis of Rationality
ERIC Educational Resources Information Center
Boostrom, Robert
2013-01-01
This chapter explores the basis of rationality, arguing that critical thinking tends to be taught in schools as a set of skills because of the failure to recognize that choosing to think critically depends on the prior development of stable sentiments or moral habits that nourish a rational self. Primary among these stable sentiments are the…
Developing Critical Rationality as a Pedagogical Aim
ERIC Educational Resources Information Center
Winch, Christopher
2004-01-01
The development of a conception of critical pedagogy is itself an aspect of the development of critical rationality within late modern societies, closely connected with the role of education in developing critical rationality. The role of critique pervades all aspects of life: for people as citizens, workers and self-determining private…
Are Grade Expectations Rational? A Classroom Experiment
ERIC Educational Resources Information Center
Hossain, Belayet; Tsigaris, Panagiotis
2015-01-01
This study examines students' expectations about their final grade. An attempt is made to determine whether students form expectations rationally. Expectations in economics, rational or otherwise, carry valuable information and have important implications in terms of both teaching effectiveness and the role of grades as an incentive structure for…
Neurophysiology and Rationality in Political Thinking.
ERIC Educational Resources Information Center
Peterson, Steven A.
Research both in cognitive psychology and psychobiology suggests that political behavior is often less rational than individuals believe it to be. Information processing, memory, and decision making are interlinked processes. Studies in cognitive psychology reveal that even though decision making requires rationality, individuals often adopt…
The Problem of Rational Moral Enlistment
ERIC Educational Resources Information Center
Tillson, John
2017-01-01
How can one bring children to recognize the requirements of morality without resorting only to non-rational means of persuasion (i.e. what rational ground can be offered to children for their moral enlistment)? Michael Hand has recently defended a foundationalist approach to answering this question and John White has responded by (a) criticizing…
The Role of Rationality in Transformative Education
ERIC Educational Resources Information Center
Arends, Jessica
2014-01-01
As scholars, we are responsible for examining the academic and pedagogical traditions from which our current approaches have developed. This includes the historical establishment of and reliance upon rationality which postmodernist scholarship argues unconsciously guides our educational motives and processes. Rationality is especially relevant to…
Rationality and Belief in Learning Mathematics
ERIC Educational Resources Information Center
Brown, Tony
2016-01-01
This paper argues that rationality and belief are mutually formative dimensions of school mathematics, where each term is more politically embedded than often depicted in the field of mathematics education research. School mathematics then presents not so much rational mathematical thought distorted by irrational beliefs but rather a particular…
Rationality and Belief in Learning Mathematics
ERIC Educational Resources Information Center
Brown, Tony
2016-01-01
This paper argues that rationality and belief are mutually formative dimensions of school mathematics, where each term is more politically embedded than often depicted in the field of mathematics education research. School mathematics then presents not so much rational mathematical thought distorted by irrational beliefs but rather a particular…
The Emotional and Moral Basis of Rationality
ERIC Educational Resources Information Center
Boostrom, Robert
2013-01-01
This chapter explores the basis of rationality, arguing that critical thinking tends to be taught in schools as a set of skills because of the failure to recognize that choosing to think critically depends on the prior development of stable sentiments or moral habits that nourish a rational self. Primary among these stable sentiments are the…
Fiber sources for complete calf starter rations.
Murdock, F R; Wallenius, R W
1980-11-01
Complete calf starter rations containing either 1) alfalfa hay, 2) cottonseed hulls, or 3) alfalfa-beet pulp as sources of fiber were fed to Holstein heifer calves at two locations on a limited milk program from 3 days to 12 wk of age. Rations were isonitrogenous and similar in content of crude fiber and acid detergent fiber. Although growth and development were normal on all rations, calves fed the cottonseed hull ration consumed more starter and gained more body weight than calves fed the other sources of fiber. The similarity of feed efficiencies, rumen pH, and molar ratios of volatile fatty acids between rations indicated no appreciable differences in rumen development or function. The growth response of calves fed the cottonseed hull ration appeared to be a result of better ration acceptability for which no reason was evident. Calves raised at Puyallup gained more body weight than calves at Pullman, and these gains were made more efficiently. These location effects may be related to seasonal differences and greater demands for production of body heat. Although the incidence of scours was less for calves fed alfalfa hay starter, the incidence and severity of bloat were higher for that ration.
Transforming Curves into Curves with the Same Shape.
ERIC Educational Resources Information Center
Levine, Michael V.
Curves are considered to have the same shape when they are related by a similarity transformation of a certain kind. This paper extends earlier work on parallel curves to curves with the same shape. Some examples are given more or less explicitly. A generalization is used to show that the theory is ordinal and to show how the theory may be applied…
Rational thinking in school-based practice.
Clark, Mary Kristen; Flynn, Perry
2011-01-01
We reflect on Alan Kamhi's (2011) prologue on balancing certainty and uncertainty as it pertains to school-based practice. In schools, rational thinking depends on effective team processes, much like professional learning communities. We consider the conditions that are required for rational thinking and how rational team dialogue confronts uncertainties. We provide suggestions for how this dialogue can be used throughout the individualized education program (IEP) process to lead to more positive experiences for all team members as well as improved student outcomes. Rational thinking in school-based practice may be manifest by closer adherence to the tenets [corrected] of the Individuals With Disabilities Education Improvement Act of 2004 (IDEIA), ultimately resulting in increased rational thought and improved student outcomes.
Ethics of rationing of nursing care.
Rooddehghan, Zahra; Yekta, Zohreh Parsa; Nasrabadi, Alireza N
2016-09-21
Rationing of various needed services, for example, nursing care, is inevitable due to unlimited needs and limited resources. Rationing of nursing care is considered an ethical issue since it requires judgment about potential conflicts between personal and professional values. The present research sought to explore aspects of rationing nursing care in Iran. This study applied qualitative content analysis, a method to explore people's perceptions of everyday life phenomena and interpret the subjective content of text data. Data collection was performed through in-depth, unstructured, face-to-face interviews with open-ended questions. The study population included Iranian nurses of all nursing positions, from clinical nurses to nurse managers. Purposive sampling was employed to select 15 female and 3 male nurses (11 clinical nurses, 3 supervisors, 1 matron, 1 nurse, and 2 members of the Nursing Council) working in hospitals of three cities in Iran. The study protocol was approved by Tehran University of Medical Sciences (91D1302870). Written informed consent was also obtained from all participants. According to the participants, rationing of nursing care consisted of two categories, that is, causes of rationing and consequences of rationing. The first category comprised three subcategories, namely, patient needs and demands, routinism, and VIP patients. The three subcategories forming the second category were missed nursing care, patient dissatisfaction, and nurses' feeling of guilt. Levels at which healthcare practices are rationed and clarity of the rationing are important structural considerations in the development of an equal, appropriate, and ethical healthcare system. Moreover, the procedure of rationing is critical as it not only influences people's lives but also reflects the values that dominate in the society. Therefore, in order to minimize the negative consequences of rationing of nursing care, further studies on the ethical dimensions of this phenomenon
Determination of the human spine curve based on laser triangulation.
Poredoš, Primož; Čelan, Dušan; Možina, Janez; Jezeršek, Matija
2015-02-05
The main objective of the present method was to automatically obtain a spatial curve of the thoracic and lumbar spine based on a 3D shape measurement of a human torso with developed scoliosis. Manual determination of the spine curve, which was based on palpation of the thoracic and lumbar spinous processes, was found to be an appropriate way to validate the method. Therefore a new, noninvasive, optical 3D method for human torso evaluation in medical practice is introduced. Twenty-four patients with confirmed clinical diagnosis of scoliosis were scanned using a specially developed 3D laser profilometer. The measuring principle of the system is based on laser triangulation with one-laser-plane illumination. The measurement took approximately 10 seconds at 700 mm of the longitudinal translation along the back. The single point measurement accuracy was 0.1 mm. Computer analysis of the measured surface returned two 3D curves. The first curve was determined by manual marking (manual curve), and the second was determined by detecting surface curvature extremes (automatic curve). The manual and automatic curve comparison was given as the root mean square deviation (RMSD) for each patient. The intra-operator study involved assessing 20 successive measurements of the same person, and the inter-operator study involved assessing measurements from 8 operators. The results obtained for the 24 patients showed that the typical RMSD between the manual and automatic curve was 5.0 mm in the frontal plane and 1.0 mm in the sagittal plane, which is a good result compared with palpatory accuracy (9.8 mm). The intra-operator repeatability of the presented method in the frontal and sagittal planes was 0.45 mm and 0.06 mm, respectively. The inter-operator repeatability assessment shows that that the presented method is invariant to the operator of the computer program with the presented method. The main novelty of the presented paper is the development of a new, non-contact method
The Characteristic Curves of Water
NASA Astrophysics Data System (ADS)
Neumaier, Arnold; Deiters, Ulrich K.
2016-09-01
In 1960, E. H. Brown defined a set of characteristic curves (also known as ideal curves) of pure fluids, along which some thermodynamic properties match those of an ideal gas. These curves are used for testing the extrapolation behaviour of equations of state. This work is revisited, and an elegant representation of the first-order characteristic curves as level curves of a master function is proposed. It is shown that Brown's postulate—that these curves are unique and dome-shaped in a double-logarithmic p, T representation—may fail for fluids exhibiting a density anomaly. A careful study of the Amagat curve (Joule inversion curve) generated from the IAPWS-95 reference equation of state for water reveals the existence of an additional branch.
Russell, Jill; Greenhalgh, Trisha
2014-09-01
The English National Health Service Constitution states that patients have the right to expect all decisions about access to medicines and treatments to be made 'rationally'. Rationality in health care can be framed as instrumental, institutional or practical. In this article, we present a case example from an ethnographic study of the work of 'Individual Funding Request' panels to explore how rationality is enacted and accounted for in deliberations about the rationing of health care in the National Health Service. Our rhetorical analysis highlights how an embodied, practical rationality emerges as a significant aspect of rationality in practice, but at the same time has a problematic status in formal accounts of decision-making. We suggest that being both 'human' and 'rational' is a 'delicate balance' and creates a dilemma for Individual Funding Request panels. Aristotle's notion of phronesis provides a useful lens for theorising our observation of panel deliberations, and we argue for greater attention to the value of narrative ethics in helping us understand the challenges faced by resource allocators. © The Author(s) 2013.
Affine Contractions on the Plane
ERIC Educational Resources Information Center
Celik, D.; Ozdemir, Y.; Ureyen, M.
2007-01-01
Contractions play a considerable role in the theory of fractals. However, it is not easy to find contractions which are not similitudes. In this study, it is shown by counter examples that an affine transformation of the plane carrying a given triangle onto another triangle may not be a contraction even if it contracts edges, heights or medians.…
Affine Contractions on the Plane
ERIC Educational Resources Information Center
Celik, D.; Ozdemir, Y.; Ureyen, M.
2007-01-01
Contractions play a considerable role in the theory of fractals. However, it is not easy to find contractions which are not similitudes. In this study, it is shown by counter examples that an affine transformation of the plane carrying a given triangle onto another triangle may not be a contraction even if it contracts edges, heights or medians.…
Backbones in the parameter plane of the Hénon map
NASA Astrophysics Data System (ADS)
Falcolini, Corrado; Tedeschini-Lalli, Laura
2016-01-01
Parameter plane (b, a) of the real Hénon map has been investigated for curves of bifurcation, curves of homoclinic heteroclinic onsets, and also searching for borders of areas variously characterized. Such curves are, in general, complicated and show singularities. Pieces of two monotone curves, spanning the (b, a) parameter plane of the real Hénon map, can be detected in four quite different studies appeared along the years 1982-2008. We study the extent of their similarity to read and interpret them into the same curves. To us, these two curves are the accumulation loci of bifurcation curves of two principal families of periodic sinks of type "period-adding machine." We call them "backbones," because they are monotone; moreover, they are the borders of some important regions in the (b, a)-plane. Hamouly and Mira in 1982 [C. R. Acad. Sc. Paris1 293, 525-528 (1982)] studied the structure of bifurcation of periodic orbits and their mutual position and intersection. Gonchenko et al. [SIAM J. Appl. Dyn. Syst. 4, 407-436 (2005)] display the continuation (in parameter plane) of the first heteroclinic connection and of the first homoclinic connection between the two fixed points of the map. Alligood and Sauer [Commun. Math. Phys. 120, 105-119 (1988)] studied parameter regions characterized by the same rotation number of the "accessible" periodic saddle. Finally, Lorenz [Physica D 237, 1689-1704 (2008)] in 2008 draws areas in the parameter plane statistically characterized by a finite attractor. In this paper, we show how these criteria interact. We therefore conjecture that the wealth of curves of homoclinic onsets could be in general hierarchized by the structure of accessible saddles.
Backbones in the parameter plane of the Hénon map.
Falcolini, Corrado; Tedeschini-Lalli, Laura
2016-01-01
Parameter plane (b, a) of the real Hénon map has been investigated for curves of bifurcation, curves of homoclinic heteroclinic onsets, and also searching for borders of areas variously characterized. Such curves are, in general, complicated and show singularities. Pieces of two monotone curves, spanning the (b, a) parameter plane of the real Hénon map, can be detected in four quite different studies appeared along the years 1982-2008. We study the extent of their similarity to read and interpret them into the same curves. To us, these two curves are the accumulation loci of bifurcation curves of two principal families of periodic sinks of type "period-adding machine." We call them "backbones," because they are monotone; moreover, they are the borders of some important regions in the (b, a)-plane. Hamouly and Mira in 1982 [C. R. Acad. Sc. Paris1 293, 525-528 (1982)] studied the structure of bifurcation of periodic orbits and their mutual position and intersection. Gonchenko et al. [SIAM J. Appl. Dyn. Syst. 4, 407-436 (2005)] display the continuation (in parameter plane) of the first heteroclinic connection and of the first homoclinic connection between the two fixed points of the map. Alligood and Sauer [Commun. Math. Phys. 120, 105-119 (1988)] studied parameter regions characterized by the same rotation number of the "accessible" periodic saddle. Finally, Lorenz [Physica D 237, 1689-1704 (2008)] in 2008 draws areas in the parameter plane statistically characterized by a finite attractor. In this paper, we show how these criteria interact. We therefore conjecture that the wealth of curves of homoclinic onsets could be in general hierarchized by the structure of accessible saddles.
[RATIONAL ASPECTS OF BACTERIOPHAGES USE].
Vakarina, A A; Kataeva, L V; Karpukhina, N F
2015-01-01
Analysis of existing aspects of bacteriophage use and study features of their lytic activity by using various techniques. Effect of monophages and associated bacteriophages (staphylococci, piopolyvalent and piocombined, intestiphage, pneumonia klebsiella and polyvalent klebsiella produced by "Microgen") was studied with 380 strains of Staphylococcus aureus and 279 cultures of Klebsiella pneumoniae in liquid and solid nutrient media. From patients with intestinal disorder, sensitivity was analyzed to 184 strains of Salmonella genus bacteria 18 serological variants to salmonella bacteriophages, 137 strains of Escherichia coli (lactose-negative, hemolytic), as well as some members of OKA groups (21 serovars) to coli-proteic and piopolyvalent bacteriophages. Lytic ability of the piobacteriophage against Klebsiella and Proteus genus bacteria was determined. Staphylococcus aureus was sensitive to staphylococcus bacteriophage in 71.6% of cases and to piobacteriophage--in 86.15% of cases. A 100% lytic ability of salmonella bacteriophage against Salmonella spp. was established. Sensitivity of E. coli of various serogroups to coli-proteic and piobacteriophage was 66 - 100%. Klebsiella, Proteus genus bacteria were sensitive to piobacteriophage in only 35% and 43.15% of cases, respectively. A more rational use of bacteriophages is necessary: development of a technique, evaluation of sensitivity of bacteria to bacteriophage, introduction of corrections into their production (expansion of bacteriophage spectra, determination and indication of their concentration in accompanying documents).
Multipulse phase resetting curves
NASA Astrophysics Data System (ADS)
Krishnan, Giri P.; Bazhenov, Maxim; Pikovsky, Arkady
2013-10-01
In this paper, we introduce and study systematically, in terms of phase response curves, the effect of dual-pulse excitation on the dynamics of an autonomous oscillator. Specifically, we test the deviations from linear summation of phase advances resulting from two small perturbations. We analytically derive a correction term, which generally appears for oscillators whose intrinsic dimensionality is >1. The nonlinear correction term is found to be proportional to the square of the perturbation. We demonstrate this effect in the Stuart-Landau model and in various higher dimensional neuronal models. This deviation from the superposition principle needs to be taken into account in studies of networks of pulse-coupled oscillators. Further, this deviation could be used in the verification of oscillator models via a dual-pulse excitation.
Quantum relative Lorenz curves
NASA Astrophysics Data System (ADS)
Buscemi, Francesco; Gour, Gilad
2017-01-01
The theory of majorization and its variants, including thermomajorization, have been found to play a central role in the formulation of many physical resource theories, ranging from entanglement theory to quantum thermodynamics. Here we formulate the framework of quantum relative Lorenz curves, and show how it is able to unify majorization, thermomajorization, and their noncommutative analogs. In doing so, we define the family of Hilbert α divergences and show how it relates with other divergences used in quantum information theory. We then apply these tools to the problem of deciding the existence of a suitable transformation from an initial pair of quantum states to a final one, focusing in particular on applications to the resource theory of athermality, a precursor of quantum thermodynamics.
Titration Curves: Fact and Fiction.
ERIC Educational Resources Information Center
Chamberlain, John
1997-01-01
Discusses ways in which datalogging equipment can enable titration curves to be measured accurately and how computing power can be used to predict the shape of curves. Highlights include sources of error, use of spreadsheets to generate titration curves, titration of a weak acid with a strong alkali, dibasic acids, weak acid and weak base, and…
ERIC Educational Resources Information Center
Khonsari, Michael M.; Horn, Douglas
1990-01-01
An algorithm is described for generating smooth curves of first-order continuity. The algorithm is composed of several cubic Bezier curves joined together at the user defined control points. Introduced is a tension control parameter which can be set thus providing additional flexibility in the design of free-form curves. (KR)
Titration Curves: Fact and Fiction.
ERIC Educational Resources Information Center
Chamberlain, John
1997-01-01
Discusses ways in which datalogging equipment can enable titration curves to be measured accurately and how computing power can be used to predict the shape of curves. Highlights include sources of error, use of spreadsheets to generate titration curves, titration of a weak acid with a strong alkali, dibasic acids, weak acid and weak base, and…
Stationary equilibrium singularity distributions in the plane
NASA Astrophysics Data System (ADS)
Newton, P. K.; Ostrovskyi, V.
2012-02-01
We characterize all stationary equilibrium point singularity distributions in the plane of logarithmic type, allowing for real, imaginary or complex singularity strengths. The dynamical system follows from the assumption that each of the N singularities moves according to the flow field generated by all the others at that point. For strength vector \\vec{\\Gamma} \\in {\\Bbb R}^N , the dynamical system is the classical point vortex system obtained from a singular discrete representation of the vorticity field from ideal, incompressible fluid flow. When \\vec{\\Gamma} \\in \\Im , it corresponds to a system of sources and sinks, whereas when \\vec{\\Gamma} \\in {\\Bbb C}^N the system consists of spiral sources and sinks discussed in Kochin et al (1964 Theoretical Hydromechanics 1 (London: Interscience)). We formulate the equilibrium problem as one in linear algebra, A \\vec{\\Gamma} = 0 , A \\in {\\Bbb C}^{N \\times N} , \\vec{\\Gamma} \\in {\\Bbb C}^N , where A is a N × N complex skew-symmetric configuration matrix which encodes the geometry of the system of interacting singularities. For an equilibrium to exist, A must have a kernel and \\vec{\\Gamma} must be an element of the nullspace of A. We prove that when N is odd, A always has a kernel, hence there is a choice of \\vec{\\Gamma} for which the system is a stationary equilibrium. When N is even, there may or may not be a non-trivial nullspace of A, depending on the relative position of the points in the plane. We provide examples of evenly and randomly distributed points on curves such as circles, figure eights, flower-petal configurations and spirals. We then show how to classify the stationary equilibria in terms of the singular spectrum of A.
Senior doctors' opinions of rational suicide.
Ginn, Stephen; Price, Annabel; Rayner, Lauren; Owen, Gareth S; Hayes, Richard D; Hotopf, Matthew; Lee, William
2011-12-01
The attitudes of medical professionals towards physician assisted dying have been widely discussed. Less explored is the level of agreement among physicians on the possibility of 'rational suicide'-a considered suicide act made by a sound mind and a precondition of assisted dying legislation. To assess attitudes towards rational suicide in a representative sample of senior doctors in England and Wales. A postal survey was conducted of 1000 consultants and general practitioners randomly selected from a commercially available database. The main outcome of interest was level of agreement with a statement about rational suicide. The corrected participation rate was 50%; 363 questionnaires were analysed. Overall 72% of doctors agreed with the possibility of rational suicide, 17% disagreed, and 11% were neutral. Doctors who identified themselves as being more religious were more likely to disagree. Some doctors who disagreed with legalisation of physician assisted suicide nevertheless agreed with the concept of rational suicide. Most senior doctors in England and Wales feel that rational suicide is possible. There was no association with specialty. Strong religious belief was associated with disagreement, although levels of agreement were still high in people reporting the strongest religious belief. Most doctors who were opposed to physician assisted suicide believed that rational suicide was possible, suggesting that some medical opposition is best explained by other factors such as concerns of assessment and protection of vulnerable patients.
A family of zero-velocity curves in the restricted three-body problem
NASA Astrophysics Data System (ADS)
Roman, R.; Szücs-Csillik, I.
2014-08-01
The equilibrium points and the curves of zero-velocity (Roche varieties) are analyzed in the frame of the regularized circular restricted three-body problem. The coordinate transformation is done with Levi-Civita generalized method, using polynomial functions of n degree. In the parametric plane, five families of equilibrium points are identified: , . These families of points correspond to the five equilibrium points in the physical plane L 1, L 2,…, L 5. The zero-velocity curves from the physical plane are transformed in Roche varieties in the parametric plane. The properties of these varieties are analyzed and the Roche varieties for n∈{1,2,…,6} are plotted. The equation of the asymptotic variety is obtained and its shape is analyzed. The slope of the Roche variety in point is obtained. For n=1 the slope obtained by Plavec and Kratochvil (1964) in the physical plane was found.
Rationing in the intensive care unit.
Truog, Robert D; Brock, Dan W; Cook, Deborah J; Danis, Marion; Luce, John M; Rubenfeld, Gordon D; Levy, Mitchell M
2006-04-01
Critical care services represent a large and growing proportion of health care expenditures. Limiting the magnitude of these costs while maintaining a just allocation of these services will require rationing. We define rationing as "the allocation of healthcare resources in the face of limited availability, which necessarily means that beneficial interventions are withheld from some individuals." Although some have maintained that rationing of health care is unethical, we argue that rationing is not only unavoidable but essential to ensuring the ethical distribution of medical goods and services. Intensivists have little to guide them in the rationing of critical care services. We have developed a taxonomy of the rationing choices faced by intensivists as a framework for ethical analysis. This taxonomy divides rationing decisions into three categories. First are those rationing decisions that may be justified by external constraints (such as not prescribing a potentially beneficial medication because it is not available on the hospital formulary). Second are those that may be justified by reference to clinical guidelines (as, for example, not prescribing a potentially beneficial medication because a valid guideline recommends treatment with a less expensive alternative). Third are those that are justified by individual clinical judgment (such as choosing which of two patients should be admitted into the last ICU bed, in the absence of any evidence-based guidance). Judgments made on the basis of clinical judgment deserve particular scrutiny, since they may mask unethical prejudices or bias. Although this taxonomy does not by itself determine which decisions are ethical, it does clarify the type of evidence that is appropriate to supporting the decision that is made. Additional work is needed to elucidate how both empirical evidence and ethical analysis can further inform the rationing decisions that arise in the taxonomy described here.
Section Curve Reconstruction and Mean-Camber Curve Extraction of a Point-Sampled Blade Surface
Li, Wen-long; Xie, He; Li, Qi-dong; Zhou, Li-ping; Yin, Zhou-ping
2014-01-01
The blade is one of the most critical parts of an aviation engine, and a small change in the blade geometry may significantly affect the dynamics performance of the aviation engine. Rapid advancements in 3D scanning techniques have enabled the inspection of the blade shape using a dense and accurate point cloud. This paper proposes a new method to achieving two common tasks in blade inspection: section curve reconstruction and mean-camber curve extraction with the representation of a point cloud. The mathematical morphology is expanded and applied to restrain the effect of the measuring defects and generate an ordered sequence of 2D measured points in the section plane. Then, the energy and distance are minimized to iteratively smoothen the measured points, approximate the section curve and extract the mean-camber curve. In addition, a turbine blade is machined and scanned to observe the curvature variation, energy variation and approximation error, which demonstrates the availability of the proposed method. The proposed method is simple to implement and can be applied in aviation casting-blade finish inspection, large forging-blade allowance inspection and visual-guided robot grinding localization. PMID:25551467
Section curve reconstruction and mean-camber curve extraction of a point-sampled blade surface.
Li, Wen-long; Xie, He; Li, Qi-dong; Zhou, Li-ping; Yin, Zhou-ping
2014-01-01
The blade is one of the most critical parts of an aviation engine, and a small change in the blade geometry may significantly affect the dynamics performance of the aviation engine. Rapid advancements in 3D scanning techniques have enabled the inspection of the blade shape using a dense and accurate point cloud. This paper proposes a new method to achieving two common tasks in blade inspection: section curve reconstruction and mean-camber curve extraction with the representation of a point cloud. The mathematical morphology is expanded and applied to restrain the effect of the measuring defects and generate an ordered sequence of 2D measured points in the section plane. Then, the energy and distance are minimized to iteratively smoothen the measured points, approximate the section curve and extract the mean-camber curve. In addition, a turbine blade is machined and scanned to observe the curvature variation, energy variation and approximation error, which demonstrates the availability of the proposed method. The proposed method is simple to implement and can be applied in aviation casting-blade finish inspection, large forging-blade allowance inspection and visual-guided robot grinding localization.
A heuristic for the distribution of point counts for random curves over a finite field
Achter, Jeffrey D.; Erman, Daniel; Kedlaya, Kiran S.; Wood, Melanie Matchett; Zureick-Brown, David
2015-01-01
How many rational points are there on a random algebraic curve of large genus g over a given finite field ? We propose a heuristic for this question motivated by a (now proven) conjecture of Mumford on the cohomology of moduli spaces of curves; this heuristic suggests a Poisson distribution with mean q+1+1/(q−1). We prove a weaker version of this statement in which g and q tend to infinity, with q much larger than g. PMID:25802415
Proposal for quantum rational secret sharing
NASA Astrophysics Data System (ADS)
Maitra, Arpita; De, Sourya Joyee; Paul, Goutam; Pal, Asim K.
2015-08-01
A rational secret sharing scheme is a game in which each party responsible for reconstructing a secret tries to maximize his or her utility by obtaining the secret alone. Quantum secret sharing schemes, derived either from quantum teleportation or from quantum error correcting code, do not succeed when we assume rational participants. This is because all existing quantum secret sharing schemes consider that the secret is reconstructed by a party chosen by the dealer. In this paper, for the first time, we propose a quantum secret sharing scheme which is resistant to rational parties. The proposed scheme is fair (everyone gets the secret), is correct, and achieves strict Nash equilibrium.
Magnetized plasma structures in laser-irradiated curved targets
NASA Astrophysics Data System (ADS)
Korneev, Philipp
2017-01-01
This work presents an extensive theoretical study of magnetic field generation effect in hollow targets with curved internal surface, known as “snail” or “escargot” targets [1]. They were recently proposed as a robust setup for generating intense spontaneous quasi-stationary magnetic fields frozen in laser-produced plasmas. The results of such studies are indispensable for planing experimental investigations and for possible applications of the curved targets, including, but not limited to, laboratory astrophysics, fast ignition, and particle acceleration.
NASA Astrophysics Data System (ADS)
Johnson, L. E.; Kim, J.; Cifelli, R.; Chandra, C. V.
2016-12-01
Potential water retention, S, is one of parameters commonly used in hydrologic modeling for soil moisture accounting. Physically, S indicates total amount of water which can be stored in soil and is expressed in units of depth. S can be represented as a change of soil moisture content and in this context is commonly used to estimate direct runoff, especially in the Soil Conservation Service (SCS) curve number (CN) method. Generally, the lumped and the distributed hydrologic models can easily use the SCS-CN method to estimate direct runoff. Changes in potential water retention have been used in previous SCS-CN studies; however, these studies have focused on long-term hydrologic simulations where S is allowed to vary at the daily time scale. While useful for hydrologic events that span multiple days, the resolution is too coarse for short-term applications such as flash flood events where S may not recover its full potential. In this study, a new method for estimating a time-variable potential water retention at hourly time-scales is presented. The methodology is applied for the Napa River basin, California. The streamflow gage at St Helena, located in the upper reaches of the basin, is used as the control gage site to evaluate the model performance as it is has minimal influences by reservoirs and diversions. Rainfall events from 2011 to 2012 are used for estimating the event-based SCS CN to transfer to S. As a result, we have derived the potential water retention curve and it is classified into three sections depending on the relative change in S. The first is a negative slope section arising from the difference in the rate of moving water through the soil column, the second is a zero change section representing the initial recovery the potential water retention, and the third is a positive change section representing the full recovery of the potential water retention. Also, we found that the soil water moving has traffic jam within 24 hours after finished first
Eight plane IPND mechanical testing.
Zhao, A.; Guarino, V.; Wood, K.; Nephew, T.; Ayres, D.; Lee, A.; High Energy Physics; FNAL
2008-03-18
A mechanical test of an 8 plane IPND mechanical prototype, which was constructed using extrusions from the testing/tryout of the 16 cell prototype extrusion die in Argonne National Laboratory, was conducted. There were 4 vertical and 4 horizontal planes in this 8 plane IPND prototype. Each vertical plane had four 16 cell extrusions, while each horizontal plane had six 16 cell extrusions. Each plane was glued together using the formulation of Devcon adhesive, Devcon 60. The vertical extrusions used in the vertical planes shares the same dimensions as the horizontal extrusions in the horizontal planes with the average web thickness of 2.1 mm and the average wall thickness of 3.1 mm. This mechanical prototype was constructed with end-seals on the both ends of the vertical extrusions. The gaps were filled with epoxy between extrusions and end-seals. The overall dimension of IPND is 154.8 by 103.1 by 21.7 inches with the weight of approximately 1200 kg, as shown in a figure. Two similar mechanical tests of 3 layer and 11 layer prototypes have been done in order to evaluate the strength of the adhesive joint between extrusions in the NOvA detector. The test showed that the IPND prototype was able to sustain under the loading of weight of itself and scintillator. Two FEA models were built to verify the measurement data from the test. The prediction from FEA slice model seems correlated reasonably well to the test result, even under a 'rough' estimated condition for the wall thickness (from an untuned die) and an unknown property of 'garage type' extrusion. A full size of FEA 3-D model also agrees very well with the test data from strain gage readings. It is worthy to point out that the stress distribution of the structure is predominantly determined by the internal pressure, while the buckling stability relies more on the loading weight from the extrusions themselves and scintillate. Results of conducted internal pressure tests, including 3- cell, 11-cell and the IPND
NASA Astrophysics Data System (ADS)
Gu, Yan; Zhao, Yonghui; Wu, Panpan; Yang, Bo; Yang, Nating; Zhu, Yan
2016-05-01
The control of the curved structure of bimetallic nanocrystals is a challenge, due to the rate differential for atom deposition and surface diffusion of alien atomic species on specific crystallographic planes of seeds. Herein, we report how to tune the degree of concavity of bimetallic PtxCoy concave nanoparticles using carboxylic acids as surfactants with an oleylamine system, leading to the specific crystallographic planes being exposed. The terminal carboxylic acids with a bridge ring or a benzene ring serving as structure regulators could direct the formation of curved faces with exposed high-index facets, and long-chain saturated fatty acids favored the production of curved faces with exposed low-index facets, while long-chain olefin acids alone benefited the formation of a flat surface with exposed low-index planes. Furthermore, these PtxCoy particles with curved faces displayed superior catalytic behaviour to cinnamaldehyde hydrogenation when compared with PtxCoy with flat faces. PtxCoy nanoparticles with curved faces exhibited over 6-fold increase in catalytic activity compared to PtxNiy nanoparticles with curved faces, and near 40-fold activity increase was observed in comparison with PtxFey nanoparticles with curved faces.The control of the curved structure of bimetallic nanocrystals is a challenge, due to the rate differential for atom deposition and surface diffusion of alien atomic species on specific crystallographic planes of seeds. Herein, we report how to tune the degree of concavity of bimetallic PtxCoy concave nanoparticles using carboxylic acids as surfactants with an oleylamine system, leading to the specific crystallographic planes being exposed. The terminal carboxylic acids with a bridge ring or a benzene ring serving as structure regulators could direct the formation of curved faces with exposed high-index facets, and long-chain saturated fatty acids favored the production of curved faces with exposed low-index facets, while long
NASA Astrophysics Data System (ADS)
Conn Henry, Richard; Kilston, S.; Shostak, S.
2008-05-01
The strong advantages of SETI searches in the ecliptic plane have been pointed out by Kilston, Shostak, and Henry (2008). In our poster we show one possible history of civilizations in the galaxy, from birth, through galactic colonization, up to death - and even beyond. Should this scenario be correct, the pattern suggests that the best hope for success in SETI is exploration of the possibility that there are a few extremely ancient but non-colonizing civilizations; civilizations that, aeons ago, detected the existence of Earth (oxygen, and hence life) and of its Moon (stabilizing Earth's rotation) via observations of transits of the Sun (hence, ecliptic, which is stable over millions of years [Laskar et al. 2004]), and have been beaming voluminous information in our direction ever since, in their faint hope (now realized) that a technological "receiving” species would appear. To maintain such a targeted broadcast would be extremely cheap for an advanced civilization. A search of a swath centered on our ecliptic plane should easily find such civilizations, if they exist. We hope to carry out such a search, using the Allen Telescope Array. http://henry.pha.jhu.edu/poster.SETI.pdf References: Kilston, Steven; Shostak, Seth; & Henry, Richard Conn; "Who's Looking at You, Kid?: SETI Advantages near the Ecliptic Plane," AbSciCon 2008, April 14-17, Santa Clara, CA.; Laskar, J., et al., A&A 428, 261, 2004 This work was supported by Maryland Space Grant Consortium.
Symmetry in finite phase plane
NASA Astrophysics Data System (ADS)
Zak, J.
2010-03-01
The known symmetries in one-dimensional systems are inversion and translations. These symmetries persist in finite phase plane, but a novel symmetry arises in view of the discrete nature of the coordinate xi and the momentum pi : xi and pi can undergo permutations. Thus, if xi assumes M discrete values, i = 0, 1,2,..., M - 1, a permutation will change the order of the set x0,x1,..., xM-1 into a new ordered set. Such a symmetry element does not exist for a continuous x-coordinate in an infinite phase plane. Thus, in a finite phase plane, translations can be replaced by permutations. This is also true for the inversion operator. The new permutation symmetry has been used for the construction of conjugate representations and for the splitting of the M-dimensional vector space into independent subspaces. This splitting is exhaustive in the sense that if M = iMi with Mi being prime numbers, the M-dimensional space splits into M1,M2,...Mn-dimensional independent subspaces. It is shown that following this splitting one can design new potentials with appropriate constants of motion. A related problem is the Weyl-Heisenberg group in the M-dimensional space which turns into a direct product of its subgroups in the Mi-dimensional subspaces. As an example we consider the case of M = 8.
Orbital Space Plane (OSP) Program
NASA Technical Reports Server (NTRS)
McKenzie, Patrick M.
2003-01-01
Lockheed Martin has been an active participant in NASA's Space Launch Initiative (SLI) programs over the past several years. SLI, part of NASA's Integrated Space Transportation Plan (ISTP), was restructured in November of 2002 to focus the overall theme of safer, more afford-able space transportation along two paths - the Orbital Space Plane Program and the Next Generation Launch Technology programs. The Orbital Space Plane Program has the goal of providing rescue capability from the International Space Station by 2008 and transfer capability for crew (and limited cargo) by 2012. The Next Generation Launch Technology program is combining research and development efforts from the 2nd Generation Reusable Launch Vehicle (2GRLV) program with cutting-edge, advanced space transportation programs (previously designated 3rd Generation) into one program aimed at enabling safe, reliable, cost-effective reusable launch systems by the middle of the next decade. Lockheed Martin is one of three prime contractors working to bring Orbital Space Plane system concepts to a system definition level of maturity by December of 2003. This paper and presentation will update the international community on the progress of the' OSP program, from an industry perspective, and provide insights into Lockheed Martin's role in enabling the vision of a safer, more affordable means of taking people to and from space.
Shape Control in Multivariate Barycentric Rational Interpolation
NASA Astrophysics Data System (ADS)
Nguyen, Hoa Thang; Cuyt, Annie; Celis, Oliver Salazar
2010-09-01
The most stable formula for a rational interpolant for use on a finite interval is the barycentric form [1, 2]. A simple choice of the barycentric weights ensures the absence of (unwanted) poles on the real line [3]. In [4] we indicate that a more refined choice of the weights in barycentric rational interpolation can guarantee comonotonicity and coconvexity of the rational interpolant in addition to a polefree region of interest. In this presentation we generalize the above to the multivariate case. We use a product-like form of univariate barycentric rational interpolants and indicate how the location of the poles and the shape of the function can be controlled. This functionality is of importance in the construction of mathematical models that need to express a certain trend, such as in probability distributions, economics, population dynamics, tumor growth models etc.
Skyrmions, rational maps, and scaling identities
Charalampidis, E. G.; Ioannidou, T. A.; Manton, N. S.
2011-03-15
Starting from approximate Skyrmion solutions obtained using the rational map ansatz, improved approximate Skyrmions are constructed using scaling arguments. Although the energy improvement is small, the change of shape clarifies whether the true Skyrmions are more oblate or prolate.
A Study of the Gamma-Ray Burst Fundamental Plane
NASA Astrophysics Data System (ADS)
Gilbertson, Christian; Dainotti, Maria; Postnikov, Sergey; Nagataki, Shigehiro; Willingale, Richard
2017-01-01
A class of long gamma-ray bursts (GRBs) with a plateau phase in their X-ray afterglows obeys a three-dimensional (3D) relation (Dainotti et al. 2016), between the rest-frame time at the end of the plateau, Ta, its corresponding X-ray luminosity, La, and the peak luminosity in the prompt emission, Lpeak. We extended the original analysis with X-ray data from July 2014 to July 2016 achieving a total sample of 183 Swift GRBs with afterglow plateaus and known redshifts. We added the most recent GRBs to the previous ‘gold sample’ (now including 45 GRBs) and obtained a relation plane with intrinsic scatter compatible within one σ with the previous result. We compared several GRB categories, such as short with extended emission, X-ray Flashes, GRBs associated with SNe, long-duration GRBs, and the gold sample, composed only by GRBs with light curves with good data coverage and relatively flat plateaus and evaluated their relation planes. We found that they are not statistically different from the fundamental plane derived from the gold sample and that the fundamental plane still has the smallest scatter. We compared the jet opening angles tabulated in literature with the angles derived using the Eiso-Egamma relation of the method in Pescalli et al. (2015) and calculated the relation plane for a sample of long GRBs accounting for the different jet opening angles. We observed that this correction does not significantly reduce the scatter. In an extended analysis, we found that the fundamental plane is independent from several prompt and afterglow parameters.
The fundamental plane of clusters of galaxies
NASA Astrophysics Data System (ADS)
D'Onofrio, M.; Bettoni, D.; Bindoni, D.; Cava, A.; Fasano, G.; Marziani, P.; Moles, M.; Moretti, A.; Poggianti, B. M.; Varela, J.
2013-04-01
We have analyzed the growth curves and the surface brightness light profiles of the clusters of the WINGS sample (Fasano et al. 2006) in the B and V bands, measuring the effective radii, the effective surface brightnesses and the total luminosities of our clusters. The similarly of the radial surface brightness profiles of early-type galaxies (ETGs) and clusters indicate that within r200 almost all clusters are virialized structures. The total luminosities L_B of clusters are found to correlate with the X-ray luminosity L_X, following approximately the same relation measured for galaxies by Eskridge et al. (1995). By coupling the photometric data with the central velocity dispersions, derived from the radial velocities of the galaxies measured by Cava et al. (2009), we were able to fit the fundamental plane (FP) of clusters of galaxies. We find that it has approximately the same slope of the FPs of early-type galaxies (ETGs) and globular clusters (GCs), but differs from them in the zero-point. This behavior can be easily explained in terms of a different contribution of dark matter (DM).
The Long Life Ration Packet (LLRP)
1991-02-18
four men for one day or one man for four days. Parachute Emergency Ration (Parachute Emergency Vest Pocket Type ). Obsolete. An individual survival food...Military Nutrition Research Title of Special Report (The Long Life Ration Packet) 12. PERSONAL AUTHOR(S) Sushma Palmer 13a. TYPE OF REPORT 113b. TIME...Health University of Michigan Edward Horton, M.D. Professor and Chairman, Medicine Un. of Vermont, Coll. of Medicine Richard Jansen, Ph.D. Professor and
[Nutrition of horses: ration calculation and assessment].
Hallebeek, J M; van 't Klooster, A T; Beynen, A C
1999-07-01
In various situations it is desirable to evaluate the diet of horses. Such situations occur when nutrition is considered as the cause of disease or symptoms or and when a diet or diet change raises concern about whether the animal is receiving sufficient nutrients. Ration evaluation consists of translating feed ingredients into nutrients supplied and comparing this with nutrient requirements. The basics of ration evaluation are illustrated by means of four examples of horse diets.
Rational emotive behavior therapy: disputing irrational philosophies.
Sacks, Susan Bendersky
2004-05-01
This article provides an overview of the concepts and techniques of rational emotive behavior therapy to distinguish it from cognitive-behavioral therapy. Rational emotive behavior therapy proposes that psychological disturbance is largely created and maintained through irrational philosophies consisting of internal absolutistic demands. This therapy strives to produce sustained and profound cognitive, emotive, and behavioral change through active, vigorous disputation of underlying irrational philosophies.
Can physicians be rational about diagnostic tests?
Young, M J; Poses, R M
1984-03-01
Concerns about diagnostic test utilization have led to interest in the role of tests in clinical decision-making, and researchers have developed guidelines for interpreting the results of diagnostic tests using Bayesian probability revision and decision analysis. Although it acknowledges the importance of these quantitative models in medical education, this article identifies major obstacles that limit their application, demonstrating that " rational " decision-making may not be rational or optimal in clinical practice.
In-plane magnetization behaviors in the Shastry-Sutherland system TbB{sub 4}: Monte Carlo simulation
Feng, J. J.; Li, W. C.; Qin, M. H. E-mail: liujm@nju.edu.cn; Xie, Y. L.; Yan, Z. B.; Liu, J.-M. E-mail: liujm@nju.edu.cn; Jia, X. T.
2015-05-07
The in-plane magnetization behaviors in TbB{sub 4} are theoretically studied using the frustrated classical XY model, including the exchange and biquadratic interactions, and the anisotropy energy. The magnetization curves at various temperatures are simulated, and the magnetic orders are uncovered by the tracking of the spin configurations. In addition, the effects of the in-plane anisotropy and biquadratic interaction on the magnetization curves are investigated in detail. The simulated results suggest that the magnetic anisotropy within the (001) plane owes to the complex interplay between these couplings, and the anisotropy term plays an important role.
Intergroup Conflict and Rational Decision Making
Martínez-Tur, Vicente; Peñarroja, Vicente; Serrano, Miguel A.; Hidalgo, Vanesa; Moliner, Carolina; Salvador, Alicia; Alacreu-Crespo, Adrián; Gracia, Esther; Molina, Agustín
2014-01-01
The literature has been relatively silent about post-conflict processes. However, understanding the way humans deal with post-conflict situations is a challenge in our societies. With this in mind, we focus the present study on the rationality of cooperative decision making after an intergroup conflict, i.e., the extent to which groups take advantage of post-conflict situations to obtain benefits from collaborating with the other group involved in the conflict. Based on dual-process theories of thinking and affect heuristic, we propose that intergroup conflict hinders the rationality of cooperative decision making. We also hypothesize that this rationality improves when groups are involved in an in-group deliberative discussion. Results of a laboratory experiment support the idea that intergroup conflict –associated with indicators of the activation of negative feelings (negative affect state and heart rate)– has a negative effect on the aforementioned rationality over time and on both group and individual decision making. Although intergroup conflict leads to sub-optimal decision making, rationality improves when groups and individuals subjected to intergroup conflict make decisions after an in-group deliberative discussion. Additionally, the increased rationality of the group decision making after the deliberative discussion is transferred to subsequent individual decision making. PMID:25461384
Point-to-plane and plane-to-plane electrostatic charge injection atomization for insulating liquids
NASA Astrophysics Data System (ADS)
Malkawi, Ghazi
An electrostatic charge injection atomizer was fabricated and used to introduce and study the electrostatic charge injection atomization methods for highly viscous vegetable oils and high conductivity low viscosity aviation fuel, JP8. The total, spray and leakage currents and spray breakup characteristics for these liquids were investigated and compared with Diesel fuel data. Jet breakup and spray atomization mechanism showed differences for vegetable oils and lower viscosity hydrocarbon fuels. For vegetable oils, a bending/spinning instability phenomenon was observed similar to the phenomenon found in liquid jets of high viscosity polymer solutions. The spray tip lengths and cone angles were presented qualitatively and quantitatively and correlated with the appropriate empirical formulas. The different stages of the breakup mechanisms for such oils, as a function of specific charges and flow rates, were discussed. In order to make this method of atomization more suitable for practical use in high flow rate applications, a blunt face electrode (plane-to-plane) was used as the charge emitter in place of a single pointed electrode (point-to-plane). This allowed the use of a multi-orifice emitter that maintained a specific charge with the flow rate increase which could not be achieved with the needle electrode. The effect of the nozzle geometry, liquid physical properties and applied bulk flow on the spray charge, total charge, maximum critical spray specific charge and electrical efficiency compared with the needle point-to-plane atomizer results was presented. Our investigation revealed that the electrical efficiency of the atomizer is dominated by the charge forced convection rate rather than charge transport by ion motilities and liquid motion by the electric field. As a result of the electric coulomb forces between the electrified jets, the multi-orifice atomizer provided a unique means of dispersing the fuel in a hollow cone with wide angles making the new
Theory of rigid-plane phonon modes in layered crystals
NASA Astrophysics Data System (ADS)
Michel, K. H.; Verberck, B.
2012-03-01
The lattice dynamics of low-frequency rigid-plane modes in metallic (graphene multilayers, GML) and in insulating (hexagonal boron-nitride multilayers, BNML) layered crystals is investigated. The frequencies of shearing and compression (stretching) modes depend on the layer number N and are presented in the form of fan diagrams. The results for GML and BNML are very similar. In both cases, only the interactions (van der Waals and Coulomb) between nearest-neighbor planes are effective, while the interactions between more distant planes are screened. A comparison with recent Raman scattering results on low-frequency shear modes in GML [Tan , Nat. Mater., in press, doi:10.1038/nmat3245, (2012)] is made. Relations with the low-lying rigid-plane phonon dispersions in the bulk materials are established. Master curves, which connect the fan diagram frequencies for any given N, are derived. Static and dynamic thermal correlation functions for rigid-layer shear and compression modes are calculated. The results might be of use for the interpretation of friction force experiments on multilayer crystals.
Langevin Equation on Fractal Curves
NASA Astrophysics Data System (ADS)
Satin, Seema; Gangal, A. D.
2016-07-01
We analyze random motion of a particle on a fractal curve, using Langevin approach. This involves defining a new velocity in terms of mass of the fractal curve, as defined in recent work. The geometry of the fractal curve, plays an important role in this analysis. A Langevin equation with a particular model of noise is proposed and solved using techniques of the Fα-Calculus.
Surface path lines in plane stokes flow driven by capillarity
Hopper, R.W.
1993-05-03
Consider the free creeping viscous plane flow in a region, bounded by a simple smooth closed curve and driven solely by surface tension. The shape evolution may in principle, and often in practice, be described by a time-dependent mapping z = {Omega}({zeta},t) of the unit circle, conformal on {vert_bar}{zeta}{vert_bar} {le} 1. It is shown that the path lines of fluid elements at the surface are determined by a first-order ordinary differential equation involving {Omega}({zeta},t), together with an initial condition. Typically, this must be integrated numerically. Velocities are not needed. The analogous theory for maps from the half-plane Im {zeta} {ge} 0 is presented. Surface path lines of a collapsing elliptic hole, in two reference frames, are calculated.
Integral Means Spectrum of Whole-Plane SLE
NASA Astrophysics Data System (ADS)
Beliaev, Dmitry; Duplantier, Bertrand; Zinsmeister, Michel
2017-07-01
We complete the mathematical analysis of the fine structure of harmonic measure on SLE curves that was initiated in Beliaev and Smirnov (Commun Math Phys 290(2):577-595, 2009), as described by the averaged integral means spectrum. For the unbounded version of whole-plane SLE as studied in Duplantier et al. (Ann Henri Poincaré 16(6):1311-1395, 2014. arXiv:1211.2451) and Loutsenko and Yermolayeva (J Stat Mech P04007, 2013), a phase transition has been shown to occur for high enough moments from the bulk spectrum towards a novel spectrum related to the point at infinity. For the bounded version of whole-plane SLE of Beliaev and Smirnov, a similar transition phenomenon, now associated with the SLE origin, is proved to exist for low enough moments, but we show that it is superseded by the earlier occurrence of the transition to the SLE tip spectrum.
Ration digestibility and mineral balance in lactating cows fed rations containing dried whey.
Schingoethe, D J; Rook, J A
1976-05-01
Including dried whey in rations of nonruminants usually increases digestibilities and mineral retention, presumably because of the lactose in the whey. A trial with total collection had five lactating cows per treatment to determine the effects of 5% dried whey product in the concentrate on digestibility of the ration and on absorption and retention of calcium, magnesium, and phosphorus. Rations included corn silage ad libitum, 3 kg alfalfa hay, and either control or dried whey product in concentrate ration at 1 kg/3 kg milk produced. Rations were balanced for content of nitrogen, calcium, magnesium, and phosphorus. Digestibilities of dry matter, nitrogen, and energy were not increased with dried whey product in the ration. Apparent absorption of calcium, magnesium, and phosphorus was not affected significantly by inclusion of whey in the ration. Productive (milk plus retained) calcium and magnesium were not increased when dried whey product was in the ration although productive phosphorus was slightly higher with the dried whey product. Adding small amounts of dried whey to a ruminant's ration will not increase mineral absorption and retention probably because tthe lactose in dried whey is fermented in the rumen and unavailabe for aiding absorption from the small intestine.
Reflection of curved shock waves
NASA Astrophysics Data System (ADS)
Mölder, S.
2017-09-01
Shock curvatures are related to pressure gradients, streamline curvatures and vorticity in flows with planar and axial symmetry. Explicit expressions, in an influence coefficient format, are used to relate post-shock pressure gradient, streamline curvature and vorticity to pre-shock gradients and shock curvature in steady flow. Using higher order, von Neumann-type, compatibility conditions, curved shock theory is applied to calculate the flow near singly and doubly curved shocks on curved surfaces, in regular shock reflection and in Mach reflection. Theoretical curved shock shapes are in good agreement with computational fluid dynamics calculations and experiment.
Reflection of curved shock waves
NASA Astrophysics Data System (ADS)
Mölder, S.
2017-03-01
Shock curvatures are related to pressure gradients, streamline curvatures and vorticity in flows with planar and axial symmetry. Explicit expressions, in an influence coefficient format, are used to relate post-shock pressure gradient, streamline curvature and vorticity to pre-shock gradients and shock curvature in steady flow. Using higher order, von Neumann-type, compatibility conditions, curved shock theory is applied to calculate the flow near singly and doubly curved shocks on curved surfaces, in regular shock reflection and in Mach reflection. Theoretical curved shock shapes are in good agreement with computational fluid dynamics calculations and experiment.
Shape Preserving Interpolation by Curves
2001-07-01
curves Given data 1i E R2 , i = 0,..., N, we consider a curve r : [a, b] -- R2 satisfying r(ti) = Ii , i = 0,..., N, (3.1) for values a = to < tj...tN = b. For a closed curve the situation is extended periodically so that Ii +N =10, ti+N =ti, i E Z, r(t+b-a) =r(t), tc R. 3.1 Desirable properties...para- meterisation). When all vi = 0, r will reduce to the usual C2 cubic spline interpolant. As vi --+ oc, the curve is ’pulled tight’ at Ii and as
SNAP Satellite Focal Plane Development
Bebek, C.; Akerlof, C.; Aldering, G.; Amanullah, R.; Astier, P.; Baltay, C.; Barrelet, E.; Basa, S.; Bercovitz, J.; Bergstrom, L.; Berstein, G.P.; Bester, M.; Bohlin, R.; Bonissent, A.; Bower, C.; Campbell, M.; Carithers, W.; Commins, E.; Day, C.; Deustua, S.; DiGennaro, R.; Ealet, A.; Ellis, R.; Emmett, W.; Eriksson, M.; Fouchez,D.; Fruchter, A.; Genat, J-F.; Goldhaber, G.; Goobar, A.; Groom, D.; Heetderks, H.; Holland, S.; Huterer, D.; Johnson, W.; Kadel, R.; Karcher,A.; Kim, A.; Kolbe, W.; Lafever, R.; Lamoureaux, J.; Lampton, M.; Lefevre, O.; Levi, M.; Levin, D.; Linder, E.; Loken, S.; Malina, R.; Mazure, A.; McKay, T.; McKee, S.; Miquel, R.; Morgan, N.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Roe, N.; Nugent, P.; Oluseyi, H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Prieto, E.; Rabinowitz,D.; Refregier, A.; Rhodes, J.; Schubnell, M.; Sholl, M.; Smadja, G.; Smith, R.; Smoot, G.; Snyder, J.; Spadafora, A.; Szymkowiak, A.; Tarle,G.; Taylor, K.; Tilquin, A.; Tomasch, A.; Vincent, D.; von der Lippe, H.; Walder, J-P.; Wang, G.
2003-07-07
The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square degree field in the visible and near-infrared wavelength regime. The requirements for the instrument suite and the present configuration of the focal plane concept are presented. A two year R&D phase, largely supported by the Department of Energy, is just beginning. We describe the development activities that are taking place to advance our preparedness for mission proposal in the areas of detectors and electronics.
NASA Astrophysics Data System (ADS)
Soler, José M.; Williams, Arthur R.
1990-11-01
Results are presented that demonstrate the effectiveness of a calculational method of electronic-structure theory. The method combines the power (tractable basis-set size) and flexibility (transition and first-row elements) of the augmented-plane-wave method with the computational efficiency of the Car-Parrinello method of molecular dynamics and total-energy minimization. Equilibrium geometry and vibrational frequencies in agreement with experiment are presented for Si, to demonstrate agreement with existing methods and for Cu, N2, and H2O to demonstrate the broader applicability of the approach.
Orbital Space Plane Cost Credibility
NASA Technical Reports Server (NTRS)
Creech, Steve
2003-01-01
NASA's largest new start development program is the Orbital Space Plane (OSP) Program. The program is currently in the formulation stage. One of the critical issues to be resolved, prior to initiating full-scale development, is establishing cost credibility of NASA s budget estimates for development, production, and operations of the OSP. This paper will discuss the processes, tools, and methodologies that NASA, along with its industry partners, are implementing to assure cost credibility for the OSP program. Results of benchmarking of current tools and the development of new cost estimating capabilities and approaches will be discussed.
Advances in String Theory in Curved Backgrounds
NASA Astrophysics Data System (ADS)
Sanchez, N. G.
A synthetic report of the advances in the study of classical and quantum string dynamics in curved backgrounds is provided, namely : the new feature of Multistring solutions; the mass spectrum of Strings in Curved backgrounds; The effect of a Cosmological Constant and of Spacial Curvature on Classical and Quantum Strings; Classical splitting of Fundamental Strings; The General String Evolution in constant Curvature Spacetimes; The Conformal Invariance Effects; Strings on plane fronted and gravitational shock waves, string falling on spacetime singularities and its spectrum. New Developments in String Gravity and String Cosmology are reported: String driven cosmology and its Predictions; The primordial gravitational wave background; Non-singular string cosmologies from Exact Conformal Field Theories; Quantum Field Theory, String Temperature and the String Phase of de Sitter space-time Hawking Radiation in String Theory and the String Phase of Black Holes; New Dual Relation between Quantum Field Theory regime and String regime and the "QFT/String Tango" New Coherent String States and Minimal Uncertainty Principle in string theory.
Reflection of sound from finite-size plane and curved surfaces
NASA Astrophysics Data System (ADS)
Rindel, Jens H.
2005-09-01
The author's research on reflectors over nearly 25 years is summarized. The influence of curvature was analyzed by a geometrical model in order to quantify the attenuation by a simple expression. Reflection from a finite-size plate was studied using the Kirchhoff-Fresnel approximation, and the design frequency for a single reflector was derived. Above the design frequency the attenuation due to the finite size can be neglected and the reflection is efficient in the specular direction. The method was extended to the case of a reflector array, and it was demonstrated that the performance of a reflector array can improve if the size of the panels is decreased. The same design frequency applies to a single reflector and a reflector array, but with different meaning; in the latter case the design frequency is the upper limit for useful reflections. This design rule was first used in the refurbishment of the concert hall of the Danish Radio in Copenhagen 1989, and later in many other halls. In order to describe the scattering due to edge diffraction, the directional characteristic of reflections from a finite-size plate has been studied and a simple approximation valid for octave bands has been derived.
Computation of Bound Orbits in the Plane of a Galaxy with a Flat Rotation Curve
ERIC Educational Resources Information Center
Bacon, M. E.; Sharrar, Amber
2010-01-01
A standard topic in an advanced undergraduate classical mechanics course is the determination of the orbits in a gravitational field. In the present paper we report on the calculation of bound orbits in the gravitational field of a spiral galaxy. Calculations such as these could serve to focus attention on an area of cutting edge astrophysics and…
Military Applications of Curved Focal Plane Arrays Developed by the HARDI Program
2011-01-01
considered one of the main founders of geometrical optics, modern photography, and cinematography . Among his inventions are the Petzval portrait lens... special frequencies, (b) the variation of intensity as a function of special frequency, (c) the image variation of intensity as a result of an...parameters for the HARDI systems to be designed for various applications. To do this, we needed a toolcomputer codeto study the effects of various
Computation of Bound Orbits in the Plane of a Galaxy with a Flat Rotation Curve
ERIC Educational Resources Information Center
Bacon, M. E.; Sharrar, Amber
2010-01-01
A standard topic in an advanced undergraduate classical mechanics course is the determination of the orbits in a gravitational field. In the present paper we report on the calculation of bound orbits in the gravitational field of a spiral galaxy. Calculations such as these could serve to focus attention on an area of cutting edge astrophysics and…
Walicka-Cupryś, Katarzyna; Drzał-Grabiec, Justyna; Mrozkowiak, Mirosław
2013-10-31
BACKGROUND. The photogrammetric method and inclinometer-based measurements are commonly employed to assess the anteroposterior curvatures of the spine. These methods are used both in clinical trials and for screening purposes. The aim of the study was to compare the parameters used to characterise the anteroposterior spinal curvatures as measured by photogrammetry and inclinometry. MATERIAL AND METHODS. The study enrolled 341 subjects: 169 girls and 172 boys, aged 4 to 9 years, from kindergartens and primary schools in Rzeszów. The anteroposterior spinal curvatures were examined by photogrammetry and with a mechanical inclinometer. RESULTS. There were significant differences in the α angle between the inclinometric and photogrammetric assessment in the Student t test (p=0.017) and the Fisher Snedecor test (p=0.0001), with similar differences in the β angle (Student's t p=0.0001, Fisher Snedecor p=0.007). For the γ angle, significant differences were revealed with Student's t test (p=0.0001), but not with the Fisher Snedecor test (p = 0.22). CONCLUSIONS. 1. Measurements of inclination of particular segments of the spine obtained with the photogrammetric method and the inclinometric method in the same study group revealed statistically significant differences. 2. The results of measurements obtained by photogrammetry and inclinometry are not comparable. 3. Further research on agreement between measurements of the anteroposterior spinal curvatures obtained using the available measurement equipment is recommended.
Stability of Alfven oscillations in a plane plasma slab
Patudin, V.M.; Sagalakov, A.M.
1983-05-01
The stability of the natural Alfven oscillations of a plane slab of a collisional, slightly nonequilibrium plasma in a uniform magnetic field is studied. An effective numerical method, a special version of the differential sweepout method, is proposed. A calculation procedure has been developed. The small-oscillation spectrum is analyzed for parabolic plasma density profiles, and neutral curves are plotted. The growth rates and critical parameters are determined. At a high plasma conductivity, both strongly and weakly localized perturbations near the axis can go unstable. For a density profile with an inflection point, weakly damped oscillations are observed near the inflection point. These oscillations can also be excited by an ion beam.
The Bolocam Galactic Plane Survey
NASA Technical Reports Server (NTRS)
Glenn, Jason; Aguirre, James; Bally, John; Battersby, Cara; Bradley, Eric Todd; Cyganowski, Claudia; Dowell, Darren; Drosback, Meredith; Dunham, Miranda K.; Evans, Neal J., II;
2009-01-01
The Bolocam Galactic Plane Survey (BGPS) is a 1.1 millimeter continuum survey of the northern Galactic Plane made with Bolocam and the Caltech Submillimeter Observatory. The coverage totals 170 square degrees, comprised of a contiguous range from -10.5 deg is less than or equal to 90.5 deg, 0.5 deg is less than or equal to b is less than or equal to 0.5 deg, with extended coverage in b in selected regions, and four targeted regions in the outer Galaxy, including: IC1396, toward the Perseus arm at l is approximately 111 deg, W3/4/5, and Gem OB1. Depths of the maps range from 30 to 60 mJy beam (sup 1). Approximately 8,400 sources were detected and the maps and source catalog have been made publicly available. Millimeter-wave thermal dust emission reveals dense regions within molecular clouds, thus the BGPS serves as a database for studies of the dense interstellar medium and star formation within the Milky Way.
The Bolocam Galactic Plane Survey
NASA Technical Reports Server (NTRS)
Glenn, Jason; Aguirre, James; Bally, John; Battersby, Cara; Bradley, Eric Todd; Cyganowski, Claudia; Dowell, Darren; Drosback, Meredith; Dunham, Miranda K.; Evans, Neal J., II; Ginsburg, Adam; Harvey, Paul; Rosolowsky, Erik; Schlingman, Wayne; Shirley, Yancy L.; Stringfellow, Guy S.; Walawender, Josh; Williams, Jonathan
2009-01-01
The Bolocam Galactic Plane Survey (BGPS) is a 1.1 millimeter continuum survey of the northern Galactic Plane made with Bolocam and the Caltech Submillimeter Observatory. The coverage totals 170 square degrees, comprised of a contiguous range from -10.5 deg is less than or equal to 90.5 deg, 0.5 deg is less than or equal to b is less than or equal to 0.5 deg, with extended coverage in b in selected regions, and four targeted regions in the outer Galaxy, including: IC1396, toward the Perseus arm at l is approximately 111 deg, W3/4/5, and Gem OB1. Depths of the maps range from 30 to 60 mJy beam (sup 1). Approximately 8,400 sources were detected and the maps and source catalog have been made publicly available. Millimeter-wave thermal dust emission reveals dense regions within molecular clouds, thus the BGPS serves as a database for studies of the dense interstellar medium and star formation within the Milky Way.
Image plane sweep volume illumination.
Sundén, Erik; Ynnerman, Anders; Ropinski, Timo
2011-12-01
In recent years, many volumetric illumination models have been proposed, which have the potential to simulate advanced lighting effects and thus support improved image comprehension. Although volume ray-casting is widely accepted as the volume rendering technique which achieves the highest image quality, so far no volumetric illumination algorithm has been designed to be directly incorporated into the ray-casting process. In this paper we propose image plane sweep volume illumination (IPSVI), which allows the integration of advanced illumination effects into a GPU-based volume ray-caster by exploiting the plane sweep paradigm. Thus, we are able to reduce the problem complexity and achieve interactive frame rates, while supporting scattering as well as shadowing. Since all illumination computations are performed directly within a single rendering pass, IPSVI does not require any preprocessing nor does it need to store intermediate results within an illumination volume. It therefore has a significantly lower memory footprint than other techniques. This makes IPSVI directly applicable to large data sets. Furthermore, the integration into a GPU-based ray-caster allows for high image quality as well as improved rendering performance by exploiting early ray termination. This paper discusses the theory behind IPSVI, describes its implementation, demonstrates its visual results and provides performance measurements.
The dyadic diffraction coefficient for a curved edge
NASA Technical Reports Server (NTRS)
Kouyoumjian, R. G.; Pathak, P. H.
1974-01-01
A compact dyadic diffraction coefficient for electromagnetic waves obliquely incident on a curved edge formed by perfectly conducting curved or plane surfaces is obtained. This diffraction coefficent remains valid in the transition regions adjacent to shadow and reflection boundaries, where the diffraction coefficients of Keller's original theory fail. The method is on Keller's method of the canonical problem, which in this case is the perfectly conducting wedge illuminated by plane, cylindrical, conical, and spherical waves. When the proper ray fixed coordinate system is introduced, the dyadic diffraction coefficient for the wedge is found to be the sum of only two dyads, and it is shown that this is also true for the dyadic diffraction coefficients of higher order edges. One dyad contains the acoustic soft diffraction coefficient; the other dyad contains the acoustic hard diffraction coefficient. The expressions for the acoustic wedge diffraction coefficients contain Fresnel integrals, which ensure that the total field is continuous at shadow and reflection boundaries. The diffraction coefficients have the same form for the different types of edge illumination; only the arguments of the Fresnel integrals are different. Since diffraction is a local phenomenon, and locally the curved edge structure is wedge shaped, this result is readily extended to the curved edge.
Dorsal apex curve of the proximal ulna.
Adikrishna, Arnold; Kim, Je Yeon; Kekatpure, Aashay L; Lee, Hyun Joo; Kim, Minjae; Jeon, In Ho
2016-01-01
To analyze the apexes and angulations along the curvature in the posterior border of the proximal ulna-termed the "dorsal apex curve" (DAC)-using the computer-aided design software. Eight pairs of normal cadaveric ulnae were analyzed. The ulnar Cartesian coordinate system was standardized using a user-defined coordinate systems feature. DAC was defined by the best-fit curvature of serial apexes in the posterior border in axial cross-sections along the ulna, whereas the best-fit curvature was obtained using polynomials interpolation method. DAC apexes in three different planes were determined by calculating the second derivative value of curve function, and subsequently, DAC angulations were calculated. Statistical analysis was performed using analysis of variance with repeated measures with significance level set as 0.001. The average ulnar length was 246±15 mm (224-274 mm). The average ratios of dorsal apex, varus apex, and edge point were 23±3% (17-27%), 33±4% (27-43%), and 10±1% (8-13%), respectively, relative to the ulnar length. The average amount of varus, dorsal, hook, and torsion angulation were 167±4° (157-172°), 176±1° (175-178°), 90±0°, and 31±10° (15-49°), respectively. We found no significant differences between left and right ulnae or between male and female ulnae. Dorsal apexes and angulations are important landmarks for surgeons when applying plates and attempting total elbow replacement surgery. This curve provides valuable information to medical manufacturers for modeling both plates and ulna components of artificial elbow joints.
Learning curves in health care.
Waldman, J Deane; Yourstone, Steven A; Smith, Howard L
2003-01-01
This article explores the uses of learning curve theory in medicine. Though effective application of learning curve theory in health care can result in higher quality and lower cost, it is seldom methodically applied in clinical practice. Fundamental changes are necessary in the corporate culture of medicine in order to capitalize maximally on the benefits of learning.
Singularities from colliding plane gravitational waves
NASA Astrophysics Data System (ADS)
Tipler, Frank J.
1980-12-01
A simple geometrical argument is given which shows that a collision between two plane gravitational waves must result in singularities. The argument suggests that these singularities are a peculiar feature of plane waves, because singularities are also a consequence of a collision between self-gravitating plane waves of other fields with arbitrarily small energy density.
Using Rational-Emotive Therapy to Prevent Classroom Problems.
ERIC Educational Resources Information Center
Webber, Jo; Coleman, Maggie
1988-01-01
Teachers are encouraged to utilize rational-emotive therapy to prevent and deal with classroom behavior problems. Rational-emotive therapy is defined, the ABC model of rational thinking briefly explained, types of irrational thinking identified, and suggestions for becoming a rational thinker are offered. Classroom examples are given. (DB)
Using Rational-Emotive Therapy to Prevent Classroom Problems.
ERIC Educational Resources Information Center
Webber, Jo; Coleman, Maggie
1988-01-01
Teachers are encouraged to utilize rational-emotive therapy to prevent and deal with classroom behavior problems. Rational-emotive therapy is defined, the ABC model of rational thinking briefly explained, types of irrational thinking identified, and suggestions for becoming a rational thinker are offered. Classroom examples are given. (DB)
Rational drug design applied to myeloperoxidase inhibition.
Van Antwerpen, P; Zouaoui Boudjeltia, K
2015-06-01
Rational drug design is a general approach using protein-structure technique in which the discovery of a ligand can be driven either by chance, screening, or rational theory. Myeloperoxidase (MPO) was rapidly identified as a therapeutical target because of its involvement in chronic inflammatory syndromes. In this context, the research of MPO inhibitors was intensified and development of new chemical entities was rationally driven by the research of ligands that enter into the MPO catalytic pocket. Actually, as soon as crystallography data of MPO have become available and its structure was virtually designed, the rational drug design has been applied to this peroxidase. Pharmaceutical industries and academic laboratories apply rational drug design on MPO by either optimizing known inhibitors or searching new molecules by high-throughput virtual screening. By these ways, they were able to find efficient MPO inhibitors and understand their interactions with the enzyme. During this quest of MPO inhibition, it appears that Glu268 is a crucial residue in order to optimize ligand-target interaction. This amino acid should be carefully considered by medicinal chemist when they design inhibitors interfering with MPO activity.
Dilemmas in rationing health care services: the case for implicit rationing.
Mechanic, D.
1995-01-01
With tension between the demand for health services and the cost of providing them, rationing is increasingly evident in all medical systems. Until recently, rationing was primarily through the ability to pay or achieved implicitly by doctors working within fixed budgets. Such forms of rationing are commonly alleged to be inequitable and inefficient and explicit rationing is advocated as more appropriate. Utilisation management in the United States and quasi-markets separating purchasing from provision in the United Kingdom are seen as ways of using resources more efficiently and are increasingly explicit. There is also advocacy to ration explicitly at the point of service. Mechanic reviews the implications of these developments and explains why explicit approaches are likely to focus conflict and dissatisfaction and be politically unstable. Explicit rationing is unlikely to be as equitable as its proponents argue and is likely to make dissatisfaction and perceived deprivation more salient. Despite its limitations, implicit rationing at the point of service is more sensitive to the complexity of medical decisions and the needs and personal and cultural preferences of patients. All systems use a mix of rationing devices, but the clinical allocation of services should substantially depend on the discretion of professionals informed by practice guidelines, outcomes research, and other informational aids. Images p1657-a p1659-a PMID:7795458
Changing Conspiracy Beliefs through Rationality and Ridiculing.
Orosz, Gábor; Krekó, Péter; Paskuj, Benedek; Tóth-Király, István; Bőthe, Beáta; Roland-Lévy, Christine
2016-01-01
Conspiracy theory (CT) beliefs can be harmful. How is it possible to reduce them effectively? Three reduction strategies were tested in an online experiment using general and well-known CT beliefs on a comprehensive randomly assigned Hungarian sample (N = 813): exposing rational counter CT arguments, ridiculing those who hold CT beliefs, and empathizing with the targets of CT beliefs. Several relevant individual differences were measured. Rational and ridiculing arguments were effective in reducing CT, whereas empathizing with the targets of CTs had no effect. Individual differences played no role in CT reduction, but the perceived intelligence and competence of the individual who conveyed the CT belief-reduction information contributed to the success of the CT belief reduction. Rational arguments targeting the link between the object of belief and its characteristics appear to be an effective tool in fighting conspiracy theory beliefs.
Structured eigenvalue problems for rational gauss quadrature
NASA Astrophysics Data System (ADS)
Fasino, Dario; Gemignani, Luca
2007-08-01
The connection between Gauss quadrature rules and the algebraic eigenvalue problem for a Jacobi matrix was first exploited in the now classical paper by Golub and Welsch (Math. Comput. 23(106), 221?230, 1969). From then on many computational problems arising in the construction of (polynomial) Gauss quadrature formulas have been reduced to solving direct and inverse eigenvalue problems for symmetric tridiagonals. Over the last few years (rational) generalizations of the classical Gauss quadrature formulas have been studied, i.e., formulas integrating exactly in spaces of rational functions. This paper wants to illustrate that stable and efficient procedures based on structured numerical linear algebra techniques can also be devised for the solution of the eigenvalue problems arising in the field of rational Gauss quadrature.
Changing Conspiracy Beliefs through Rationality and Ridiculing
Orosz, Gábor; Krekó, Péter; Paskuj, Benedek; Tóth-Király, István; Bőthe, Beáta; Roland-Lévy, Christine
2016-01-01
Conspiracy theory (CT) beliefs can be harmful. How is it possible to reduce them effectively? Three reduction strategies were tested in an online experiment using general and well-known CT beliefs on a comprehensive randomly assigned Hungarian sample (N = 813): exposing rational counter CT arguments, ridiculing those who hold CT beliefs, and empathizing with the targets of CT beliefs. Several relevant individual differences were measured. Rational and ridiculing arguments were effective in reducing CT, whereas empathizing with the targets of CTs had no effect. Individual differences played no role in CT reduction, but the perceived intelligence and competence of the individual who conveyed the CT belief-reduction information contributed to the success of the CT belief reduction. Rational arguments targeting the link between the object of belief and its characteristics appear to be an effective tool in fighting conspiracy theory beliefs. PMID:27790164
Autonomy, rationality and the wish to die.
Clarke, D M
1999-01-01
Although suicide has traditionally carried a negative sanction in Western societies, this is now being challenged, and while there remains substantial public concern surrounding youth and elder suicide, there is a paradoxical push to relax the prohibition under certain circumstances. Central to the arguments behind this are the principles of respect for autonomy and the importance of rationality. It is argued here that the concepts of rationality and autonomy, while valuable, are not strong enough to substantiate a categorical "right to suicide" and that the concepts of "understandability" and "respect" are more useful and able to provide the foundation for responding to a person expressing a wish to die. Roman suicide, sometimes held as an example of "rational suicide", illustrates the effects of culture, tradition and values on the attitudes to, and the practice of, suicide. PMID:10635498
Broken chiral symmetry on a null plane
Beane, Silas R.
2013-10-15
On a null-plane (light-front), all effects of spontaneous chiral symmetry breaking are contained in the three Hamiltonians (dynamical Poincaré generators), while the vacuum state is a chiral invariant. This property is used to give a general proof of Goldstone’s theorem on a null-plane. Focusing on null-plane QCD with N degenerate flavors of light quarks, the chiral-symmetry breaking Hamiltonians are obtained, and the role of vacuum condensates is clarified. In particular, the null-plane Gell-Mann–Oakes–Renner formula is derived, and a general prescription is given for mapping all chiral-symmetry breaking QCD condensates to chiral-symmetry conserving null-plane QCD condensates. The utility of the null-plane description lies in the operator algebra that mixes the null-plane Hamiltonians and the chiral symmetry charges. It is demonstrated that in a certain non-trivial limit, the null-plane operator algebra reduces to the symmetry group SU(2N) of the constituent quark model. -- Highlights: •A proof (the first) of Goldstone’s theorem on a null-plane is given. •The puzzle of chiral-symmetry breaking condensates on a null-plane is solved. •The emergence of spin-flavor symmetries in null-plane QCD is demonstrated.
Gu, Yan; Zhao, Yonghui; Wu, Panpan; Yang, Bo; Yang, Nating; Zhu, Yan
2016-06-07
The control of the curved structure of bimetallic nanocrystals is a challenge, due to the rate differential for atom deposition and surface diffusion of alien atomic species on specific crystallographic planes of seeds. Herein, we report how to tune the degree of concavity of bimetallic PtxCoy concave nanoparticles using carboxylic acids as surfactants with an oleylamine system, leading to the specific crystallographic planes being exposed. The terminal carboxylic acids with a bridge ring or a benzene ring serving as structure regulators could direct the formation of curved faces with exposed high-index facets, and long-chain saturated fatty acids favored the production of curved faces with exposed low-index facets, while long-chain olefin acids alone benefited the formation of a flat surface with exposed low-index planes. Furthermore, these PtxCoy particles with curved faces displayed superior catalytic behaviour to cinnamaldehyde hydrogenation when compared with PtxCoy with flat faces. PtxCoy nanoparticles with curved faces exhibited over 6-fold increase in catalytic activity compared to PtxNiy nanoparticles with curved faces, and near 40-fold activity increase was observed in comparison with PtxFey nanoparticles with curved faces.
Smov Baseline Focal Plane Check
NASA Astrophysics Data System (ADS)
Gilmozzi, Roberto
1994-01-01
This test will be executed during the period after the servicing mission and before the extension of the COSTAR assembly. Its purpose is to verify that the FOS, HRS, and FOC focal planes have not been altered by the activities performed by Story and the Astronauts during the servicing mission. A large unknown deviation in aperture position would severly impact subsequent COSTAR alignment activities. If this test reveals a deviation, we may be able to compensate for any offsets prior to the complex and delicate COSTAR alignment calibrations. This enhanced version of the Heptathlon is designed to verify course alignments and measure relative aperture positions to within a few arcsecs. SPECIAL REQUIREMENTS: ***This test uses pre-servicing parameters for HRS, FOS, and FOC and the Cycle 4 parameters for WFPC2.*** ***This test requires special alignment and special guide stars.** ***This test requires special commanding for telemetry setups.**
Thermodynamics of black plane solution
NASA Astrophysics Data System (ADS)
Rodrigues, Manuel E.; Jardim, Deborah F.; Houndjo, Stéphane J. M.; Myrzakulov, Ratbay
2013-11-01
We obtain a new phantom black plane solution in D of the Einstein-Maxwell theory coupled with a cosmological constant. We analyse their basic properties, as well as its causal structure, and obtain the extensive and intensive thermodynamic variables, as well as the specific heat and the first law. Through the specific heat and the so-called geometric methods, we analyse in detail their thermodynamic properties, the extreme and phase transition limits, as well as the local and global stabilities of the system. The normal case is shown with an extreme limit and the phantom one with a phase transition only for null mass, which is physically inaccessible. The systems present local and global stabilities for certain values of the entropy density with respect to the electric charge, for the canonical and grand canonical ensembles.
NASA Astrophysics Data System (ADS)
McCormick, Andrew; Young, Bruce A.; Mahadevan, L.
2012-02-01
We develop a new computational model of elastic rods, taking into account shear and full rotational dynamics, as well as friction, adhesion, and collision. This model is used to study the movement of snakes in different environments. By applying different muscular activation patterns to the snake, we observe many different patterns of motion, from planar undulation to sudden strikes. Many of the most interesting behaviors involve the snake rising out of the horizontal plane in the vertical direction. Such behaviors include a sand snake sidewinding over the hot desert sand and a cobra rearing up into a defensive striking position. Experimental videos of live snakes are analyzed and compared with computational results. We identify and explain a new form of movement previously unobserved: ``collateral locomotion.''
Functional Aesthetic Occlusal Plane (FAOP)
Câmara, Carlos Alexandre; Martins, Renato Parsekian
2016-01-01
ABSTRACT Introduction: A reasonable exposure of incisors and gingival tissues is generally considered more attractive than excess or lack of exposure. A reasonable gingival exposure is considered to be around 0 to 2 mm when smiling and 2-4 mm exposure of the maxillary incisor edge when the lips are at rest. Objective: The aim of this paper is to present the Functional Aesthetic Occlusal Plane (FAOP), which aims to help in the diagnosis of the relationships established among molars, incisors and the upper lip. Conclusion: FAOP can complement an existing and established orthodontic treatment plan, facilitating the visualization of functional and aesthetic demands by giving a greater focus on the position of incisors in the relationship established among the incisors, molars and the upper lip stomion. PMID:27653271
[The role of economics in fair rationing].
Prenzler, A
2012-10-01
For several years academic disciplines have discussed the potential conflict between scarcity of funding and fair health care. This review article shows the necessity of involving economic scientists in this discussion as well as their contribution to rationalisation, prioritisation and rationing of health care services. Thereby, it becomes clear that rationing and justice are not a contradiction per se. The interdisciplinary discussion in Germany needs less disciplinary egotism and more willingness to seek solutions and compromises. In this context the procedures followed in other countries can serve as examples.
Rationality: a social-epistemology perspective
Vanpoucke, Danny E. P.; Douven, Igor
2014-01-01
Both in philosophy and in psychology, human rationality has traditionally been studied from an “individualistic” perspective. Recently, social epistemologists have drawn attention to the fact that epistemic interactions among agents also give rise to important questions concerning rationality. In previous work, we have used a formal model to assess the risk that a particular type of social-epistemic interactions lead agents with initially consistent belief states into inconsistent belief states. Here, we continue this work by investigating the dynamics to which these interactions may give rise in the population as a whole. PMID:24994987
The Rational Hybrid Monte Carlo algorithm
NASA Astrophysics Data System (ADS)
Clark, Michael
2006-12-01
The past few years have seen considerable progress in algorithmic development for the generation of gauge fields including the effects of dynamical fermions. The Rational Hybrid Monte Carlo (RHMC) algorithm, where Hybrid Monte Carlo is performed using a rational approximation in place the usual inverse quark matrix kernel is one of these developments. This algorithm has been found to be extremely beneficial in many areas of lattice QCD (chiral fermions, finite temperature, Wilson fermions etc.). We review the algorithm and some of these benefits, and we compare against other recent algorithm developements. We conclude with an update of the Berlin wall plot comparing costs of all popular fermion formulations.
The prevalence of tori amongst constant mean curvature planes in R3
NASA Astrophysics Data System (ADS)
Carberry, Emma; Schmidt, Martin Ulrich
2016-08-01
Constant mean curvature (CMC) tori in Euclidean 3-space are described by an algebraic curve, called the spectral curve, together with a line bundle on this curve and a point on S1, called the Sym point. For a given spectral curve the possible choices of line bundle and Sym point are easily described. The space of spectral curves of tori is totally disconnected. Hence to characterise the "moduli space" of CMC tori one should, for each genus g, determine the closure Pg bar of spectral curves of CMC tori within the spectral curves of CMC planes having spectral genus g. We identify a real subvariety Rg and a subset Sg ⊆Rg such that Rmaxg ⊆Pg bar ⊆Sg, where Rmaxg denotes the points of Rg having maximal dimension. The lowest spectral genus for which tori exist is g = 2 and in this case R2 = Rmax2 =P2 bar =S2. For g > 2, we conjecture that Rg ⊋ Rmaxg =Sg. We give a number of alternative characterisations of Rmaxg and in particular introduce a new integer invariant of a CMC plane of finite type, called its winding number.
Polish spaces of causal curves
NASA Astrophysics Data System (ADS)
Miller, Tomasz
2017-06-01
We propose and study a new approach to the topologization of spaces of (possibly not all) future-directed causal curves in a stably causal spacetime. It relies on parametrizing the curves ;in accordance; with a chosen time function. Thus obtained topological spaces of causal curves are separable and completely metrizable, i.e. Polish. The latter property renders them particularly useful in the optimal transport theory. To illustrate this fact, we explore the notion of a causal time-evolution of measures in globally hyperbolic spacetimes and discuss its physical interpretation.
Accelerating Around an Unbanked Curve
2006-02-01
FEB 2006 2. REPORT TYPE 3. DATES COVERED 00-00-2006 to 00-00-2006 4. TITLE AND SUBTITLE Accelerating Around an Unbanked Curve 5a. CONTRACT...December 2004 issue of TPT presented a problem concerning how a car should acceler-ate around an unbanked curve of constant radius r starting from rest...Accelerating Around an Unbanked Curve Carl E. Mungan, U.S. Naval Academy, Annapolis, MD 100 THE PHYSICS TEACHER ◆ Vol. 44, February 2006 The shapes
Curved conveyor section guide assembly
Truszczinski, H.
1981-02-03
A guide assembly for a curved conveyor section of a scraperchain conveyor guides the scraper assembly from a first straight conveyor portion round the curved conveyor section to a second straight conveyor portion. This guiding is accomplished by a pair of independently rotatable pulley wheels. A further pair of independently rotatable pulley wheels are provided to guide the drive chain of a plough round the curved conveyor section. This enables the plough to be driven to and fro along the first straight conveyor portion by a drive station attached to the second straight conveyor portion adjacent to the guide assembly.
Predictiveness curves in virtual screening.
Empereur-Mot, Charly; Guillemain, Hélène; Latouche, Aurélien; Zagury, Jean-François; Viallon, Vivian; Montes, Matthieu
2015-01-01
In the present work, we aim to transfer to the field of virtual screening the predictiveness curve, a metric that has been advocated in clinical epidemiology. The literature describes the use of predictiveness curves to evaluate the performances of biological markers to formulate diagnoses, prognoses and assess disease risks, assess the fit of risk models, and estimate the clinical utility of a model when applied to a population. Similarly, we use logistic regression models to calculate activity probabilities related to the scores that the compounds obtained in virtual screening experiments. The predictiveness curve can provide an intuitive and graphical tool to compare the predictive power of virtual screening methods. Similarly to ROC curves, predictiveness curves are functions of the distribution of the scores and provide a common scale for the evaluation of virtual screening methods. Contrarily to ROC curves, the dispersion of the scores is well described by predictiveness curves. This property allows the quantification of the predictive performance of virtual screening methods on a fraction of a given molecular dataset and makes the predictiveness curve an efficient tool to address the early recognition problem. To this last end, we introduce the use of the total gain and partial total gain to quantify recognition and early recognition of active compounds attributed to the variations of the scores obtained with virtual screening methods. Additionally to its usefulness in the evaluation of virtual screening methods, predictiveness curves can be used to define optimal score thresholds for the selection of compounds to be tested experimentally in a drug discovery program. We illustrate the use of predictiveness curves as a complement to ROC on the results of a virtual screening of the Directory of Useful Decoys datasets using three different methods (Surflex-dock, ICM, Autodock Vina). The predictiveness curves cover different aspects of the predictive power of
Sagittal plane correction in idiopathic scoliosis.
de Jonge, Tamás; Dubousset, Jean F; Illés, Tamás
2002-04-01
Patients with idiopathic scoliosis who had undergone posterior fusion by means of posterior multisegmented hook instrumentation were studied retrospectively. To present the changes in projected thoracic hypokyphosis and the behavior of lumbar lordosis within and below the fusion. Scoliosis is a three-dimensional deformity of the spine. The idiopathic cases usually exhibit a flattening of the sagittal curves, which had further deteriorated when the Harrington technique was used. The consequences included the flat back, angular increase of the lumbar lordosis below the fusion, and low back pain. Previous studies showed no or only moderate correction of thoracic hypokyphosis when using Cotrel-Dubousset instrumentation or its modifications were used. Harrington rod systems resulted in decreased lumbar lordosis in the fusion area and increased lordosis below the fusion. No background data were found concerning the effects of multisegmented hook instrumentation on the lumbar spine within and below the fusion. For this study, 306 patients with idiopathic scoliosis who had undergone posterior spinal fusion with multisegmented hook systems using the derotation maneuver were analyzed after a mean follow-up period of 5 years and 4 months. The coronal plane curvature, the sagittal plane projection of the thoracic kyphosis, and the lumbar lordosis within and below the fusion were evaluated. The average coronal plane correction was 67.1%. Analysis of the sagittal contours demonstrated that the preoperative thoracic hypokyphosis (less than 20 degrees between T4 and T12) increased by an average of 12 degrees, and that 55.1% of hypokyphotic backs were corrected to the normal range (20 degrees to 40 degrees ). In patients with frank lordosis (kyphosis less than 10 degrees ), the degree of correction was higher (average, 16 degrees ), but complete correction was achieved in only 38.5% of the cases. In patients with mild lordosis (kyphosis between 10 degrees and 20 degrees ), the
2-tier in-plane motion correction and out-of-plane motion filtering for contrast-enhanced ultrasound
Ta, Casey N.; Eghtedari, Mohammad; Mattrey, Robert F.; Kono, Yuko; Kummel, Andrew C.
2014-01-01
Objectives Contrast-enhanced ultrasound (CEUS) cines of focal liver lesions (FLL) can be quantitatively analyzed to measure tumor perfusion on a pixel-by-pixel basis for diagnostic indication. However, CEUS cines acquired freehand and during free breathing cause non-uniform in-plane and out-of-plane motion from frame to frame. These motions create fluctuations in the time-intensity curves (TIC), reducing accuracy of quantitative measurements. Out-of-plane motion cannot be corrected by image registration in 2D CEUS and degrades the quality of in-plane motion correction (IPMC). A 2-tier IPMC strategy and adaptive out-of-plane motion filter (OPMF) are proposed to provide a stable correction of non-uniform motion to reduce the impact of motion on quantitative analyses. Materials and Methods 22 cines of FLLs were imaged with dual B-mode and contrast specific imaging to acquire a 3-minute TIC. B-mode images were analyzed for motion, and the motion correction was applied to both B-mode and contrast images. For IPMC, the main reference frame was automatically selected for each cine, and subreference frames were selected in each respiratory cycle and sequentially registered toward the main reference frame. All other frames were sequentially registered toward the local subreference frame. Four OPMFs were developed and tested: subsample Normalized Correlation (NC), subsample Sum of Absolute Differences (SAD), mean frame NC, and histogram. The frames that were most dissimilar to the OPMF reference frame using one of the four above criteria in each respiratory cycle were adaptively removed by thresholding against the low-pass filter of the similarity curve. OPMF was quantitatively evaluated by an out-of-plane motion metric (OPMM) that measured normalized variance in the high-pass filtered time-intensity curve within the tumor region-of-interest with low OPMM being the goal. IPMC and OPMF results were qualitatively evaluated by two blinded observers who ranked the motion in the
An automatic recognition and parameter extraction method for structural planes in borehole image
NASA Astrophysics Data System (ADS)
Wang, Chuanying; Zou, Xianjian; Han, Zengqiang; Wang, Yiteng; Wang, Jinchao
2016-12-01
As a breakthrough in borehole imaging technology, digital panoramic borehole camera technology has been widely employed. The high-resolution panoramic borehole images can accurately reproduce the geometric features of structural planes. However, the detection of these features is usually done manually, which is both time-consuming and introduces human errors. To solve this problem, this paper presents a method for the automatic recognition and parameter extraction of borehole geometric features of camera images. In this method, the image's gray and gradient level, and also their projection on the depth axis are used to identify the locations of structural planes. Afterwards, iterative matching is employed by using a template of sinusoidal function to search for structural planes in the identified image blocks. Finally, optimal sine curves are selected as the feature curves of structural planes, and their related parameters are converted into structural plane parameters required for engineering, such as their positions, dip directions, dip angles and fracture widths. The method can automatically identify all of structural planes throughout the whole borehole camera image in a continuous and rapid manner, and obtain the corresponding structural parameters. It has proven highly reliable, accurate and efficient.
Geometric plane shapes for computer-generated holographic engraving codes
NASA Astrophysics Data System (ADS)
Augier, Ángel G.; Rabal, Héctor; Sánchez, Raúl B.
2017-04-01
We report a new theoretical and experimental study on hologravures, as holographic computer-generated laser-engravings. A geometric theory of images based on the general principles of light ray behaviour is shown. The models used are also applicable for similar engravings obtained by any non-laser method, and the solutions allow for the analysis of particular situations, not only in the case of light reflection mode, but also in transmission mode geometry. This approach is a novel perspective allowing the three-dimensional (3D) design of engraved images for specific ends. We prove theoretically that plane curves of very general geometric shapes can be used to encode image information onto a two-dimensional (2D) engraving, showing notable influence on the behaviour of reconstructed images that appears as an exciting investigation topic, extending its applications. Several cases of code using particular curvilinear shapes are experimentally studied. The computer-generated objects are coded by using the chosen curve type, and engraved by a laser on a plane surface of suitable material. All images are recovered optically by adequate illumination. The pseudoscopic or orthoscopic character of these images is considered, and an appropriate interpretation is presented.
A Study of the Gamma-Ray Burst Fundamental Plane
NASA Astrophysics Data System (ADS)
Dainotti, Maria; Gilbertson, Christian; Postnikov, Sergey; Nagataki, Shigehiro; Willingale, Richard
2017-01-01
A class of long gamma-ray bursts (GRBs) with a plateau phase in their X-ray afterglows obeys a three dimensional (3D) relation (Dainotti et al. 2016), 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, $L_{peak}$, which is an extension of the two dimensional Dainotti relation. This 3D relation identifies a GRB fundamental plane whose existence we confirmed. We extended the original analysis with X-ray data from July 2014 to July 2016 achieving a total sample of 183 {\\it Swift} GRBs with afterglow plateaus and known redshifts. We added the most recent GRBs to the previous `gold sample' (now including 45 GRBs) and obtained an intrinsic scatter compatible within one $\\sigma$ with the previous result. We compared several GRB categories, such as short with extended emission, X-ray Flashes, GRBs associated with SNe, 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 only by GRBs with light curves with good data coverage and relatively flat plateaus. We evaluated the relation planes for each of the mentioned categories and showed that they are not statistically different from the plane derived from the gold sample and that the fundamental plane derived from the gold sample has an intrinsic scatter smaller than any plane derived from the other sample categories. We compared the jet opening angles tabulated in literature with the angles derived using the $E_{iso}-E_{gamma}$ relation of the method in Pescalli et al. (2015) and calculated the relation plane for a sample of long GRBs accounting for the different jet opening angles. We observed that this correction does not significantly reduce the scatter. In an extended analysis, we found that the fundamental plane is independent from several prompt and afterglow parameters, such as the jet opening angle, $\\theta
Nonlinear mechanics of rigidifying curves
NASA Astrophysics Data System (ADS)
Al Mosleh, Salem; Santangelo, Christian
2017-07-01
Thin shells are characterized by a high cost of stretching compared to bending. As a result isometries of the midsurface of a shell play a crucial role in their mechanics. In turn, curves on the midsurface with zero normal curvature play a critical role in determining the number and behavior of isometries. In this paper, we show how the presence of these curves results in a decrease in the number of linear isometries. Paradoxically, shells are also known to continuously fold more easily across these rigidifying curves than other curves on the surface. We show how including nonlinearities in the strain can explain these phenomena and demonstrate folding isometries with explicit solutions to the nonlinear isometry equations. In addition to explicit solutions, exact geometric arguments are given to validate and guide our analysis in a coordinate-free way.
Tilted planes in 3D image analysis
NASA Astrophysics Data System (ADS)
Pargas, Roy P.; Staples, Nancy J.; Malloy, Brian F.; Cantrell, Ken; Chhatriwala, Murtuza
1998-03-01
Reliable 3D wholebody scanners which output digitized 3D images of a complete human body are now commercially available. This paper describes a software package, called 3DM, being developed by researchers at Clemson University and which manipulates and extracts measurements from such images. The focus of this paper is on tilted planes, a 3DM tool which allows a user to define a plane through a scanned image, tilt it in any direction, and effectively define three disjoint regions on the image: the points on the plane and the points on either side of the plane. With tilted planes, the user can accurately take measurements required in applications such as apparel manufacturing. The user can manually segment the body rather precisely. Tilted planes assist the user in analyzing the form of the body and classifying the body in terms of body shape. Finally, titled planes allow the user to eliminate extraneous and unwanted points often generated by a 3D scanner. This paper describes the user interface for tilted planes, the equations defining the plane as the user moves it through the scanned image, an overview of the algorithms, and the interaction of the tilted plane feature with other tools in 3DM.
Flow over riblet curved surfaces
NASA Astrophysics Data System (ADS)
Loureiro, J. B. R.; Silva Freire, A. P.
2011-12-01
The present work studies the mechanics of turbulent drag reduction over curved surfaces by riblets. The effects of surface modification on flow separation over steep and smooth curved surfaces are investigated. Four types of two-dimensional surfaces are studied based on the morphometric parameters that describe the body of a blue whale. Local measurements of mean velocity and turbulence profiles are obtained through laser Doppler anemometry (LDA) and particle image velocimetry (PIV).
Growth and energy budget of juvenile lenok Brachymystax lenok in relation to ration level
NASA Astrophysics Data System (ADS)
Liu, Yang; Li, Zhongjie; Zhang, Tanglin; Yuan, Jing; Mou, Zhenbo; Liu, Jiashou
2015-03-01
We evaluated the effect of ration level (RL) on the growth and energy budget of lenok Brachymystax lenok. Juvenile lenok (initial mean body weight 3.06±0.13 g) were fed for 21 d at five different ration levels: starvation, 2%, 3%, 4% bwd (body weight per day, based on initial mean values), and apparent satiation. Feed consumption, apparent digestibility, and growth were directly measured. Specific growth rates in terms of wet weight, dry weight, protein, and energy increased logarithmically with an increase in ration levels. The relationship between specific growth rate in terms of wet weight (SGRw, %/d) and RL (%) was characterized by a decelerating curve: SGRw=-1.417+3.166ln(RL+1). The apparent digestibility coefficients of energy exhibited a decreasing pattern with increasing ration level, and there was a significant difference among different RLs. Body composition was significantly affected by ration size. The relationship between feed efficiency rate in terms of energy (FERe) and RL was: FERe=-14.167+23.793RL-3.367(RL)2, and the maximum FERe was observed at a 3.53% ration. The maintenance requirement for energy of juvenile lenok was 105.39 kJ BW (kg)-0.80/d, the utilization efficiency of DE for growth was 0.496. The energy budget equation at satiation was: 100IE=29.03FE+5.78(ZE+UE)+39.56 HE+25.63 RE, where IE is feed energy, FE is fecal energy, ZE+UE is excretory energy, HE is heat production, and RE is recovered energy. Our results suggest that the most suitable feeding rate for juvenile lenok aquaculture for wet weight growth is 2.89% bwd, whereas for energy growth, the suggested rate is 3.53% bwd at this growth stage.
Line constrained between two curves
NASA Astrophysics Data System (ADS)
Ahmad, Afida; Ali, Jamaludin Md.
2013-04-01
In this paper, the method of finding the line constrained between two quadratic Bezier curves and also finding the line constrained between a quadratic Bezier curve and a circle is presented. The application of the line constrained can be used in the construction of railway tracks between any obstacle or rolling a ball to the other side of a wall in a way that it just touches the wall. The method used is by using equal root properties of a quadratic equation in order to find one point where the line touches the curve. The work examples involved different curve orientations and different circle positions. Mathematica software is used to compute the solutions for the line constrained and present the solutions graphically. By using the method proposed, the number of intersection points obtained is used to determine the number of lines constrained between two curves and between a curve and a circle. The conclusion on whether all lines are acceptable to be considered as the line constrained are depending on the application of the line.
A cephalometric study to determine the center of anteroposterior curve of occlusion in the cranium.
Kumar, Thota Kiran; Thomas, Vivek; Nilawar, Sanjay; Balamurugan, R; Marwaha, Baldeep Singh; Vinod, V
2013-09-01
Proper management of the occlusal plane is an essential consideration when multiple long span posterior restorations are designed. When restorations are added to an existing tooth arrangement characterized by rotated, tipped or extruded teeth, excursive interferences may be incorporated. The curve of Spee which exists in natural dentition, allows harmony to exist between the anterior teeth and the condylar guidance. Broadrick fag or occlusal plane analyzer is used to assist in the reproduction of tooth morphology that is commensurate with the curve of Spee when posterior restorations are designed; its use prevents the introduction of protrusive interferences. The current study determines the relationship of the center of anteroposterior curve of occlusion in the cranium and its relationship to other cephalometric landmarks and also evaluates the relationship of anteroposterior curve of occlusion to the condyle.
Aronsson, D D; Stokes, I A; Ronchetti, P J; Labelle, H B
1994-05-01
Fourteen patients with cerebral palsy (CP), 12 with Friedreich's ataxia (FA) and 26 with adolescent idiopathic scoliosis (AIS) were studied to determine whether the shape of the scoliosis curve differs between these categories. The slope of the regression relationship between vertebral rotation and lateral deviation was greater for the CP group compared with the FA and AIS groups. The authors conclude that the scoliosis curve pattern of children with Friedreich's ataxia and adolescent idiopathic scoliosis is similar. In contrast, the scoliosis curve of children with CP was distinctly different, with more rotation of the apical vertebrae into the convexity of the scoliosis curve (transverse plane deformity) in relation to the amount of lateral deviation of the apical vertebrae from the spinal axis (coronal plane deformity).
The Assessment of Rational Thinking: IQ ? RQ
ERIC Educational Resources Information Center
Stanovich, Keith E.; West, Richard F.
2014-01-01
In this article the authors argue that distinguishing between rationality and intelligence helps explain how people can be, at the same time, intelligent and irrational (Stanovich, 2009). As such, researchers need to study separately the individual differences in cognitive skills that underlie intelligence and the individual differences in…
Medicine, ethics and religion: rational or irrational?
Orr, R D; Genesen, L B
1998-01-01
Savulescu maintains that our paper, which encourages clinicians to honour requests for "inappropriate treatment" is prejudicial to his atheistic beliefs, and therefore wrong. In this paper we clarify and expand on our ideas, and respond to his assertion that medicine, ethics and atheism are objective, rational and true, while religion is irrational and false. PMID:9873978
Opinion Expression as a Rational Behavior.
ERIC Educational Resources Information Center
Kim, Sei-Hill
This study looks at individuals' opinion expressions as a rational behavior based on a conscious calculus of expected benefits and costs (economic analysis). The influences of "issue benefit,""opinion congruence," and "issue knowledge," as sources of benefits and costs on opinion expression were hypothesized and tested. The study also examined the…
Rational Rhymes for Addressing Common Childhood Issues
ERIC Educational Resources Information Center
Warren, Jeffrey M.
2011-01-01
Music-based interventions are valuable tools counselors can use when working with children. Specific types of music-based interventions, such as songs or rhymes, can be especially pertinent in addressing the thoughts, feelings, and behaviors of children. Rational-emotive behavior therapy (REBT) provides a therapeutic framework that encourages…
Imitation in Infancy: Rational or Motor Resonance?
ERIC Educational Resources Information Center
Paulus, Markus; Hunnius, Sabine; Vissers, Marlies; Bekkering, Harold
2011-01-01
The present study investigates the contribution of 2 mechanisms to imitation in infancy. The principle of rational action suggests that infants normatively evaluate the efficiency of observed actions. In contrast, it has been proposed that motor resonance (i.e., the mapping of others' actions onto one's own motor repertoire) plays a central role…
The Rational-Emotive Approach: A Critique
ERIC Educational Resources Information Center
Morris, G. Barry
1976-01-01
The critique of Rational-Emotive Therapy aims criticism at Ellis' concept of irrationality, analysis of human behavior and therapeutic techniques. Ellis suggests that his critic's claims lack the support of experimental evidence. He further suggests that an "existential" bias pervades which differs from his own brand of…
Expressive Thought and Non-Rational Inquiry.
ERIC Educational Resources Information Center
Newton, Richard F.
A significant problem with inquiry teaching is that too much emphasis is placed on inquiry as a logical, scientific, and rational way of knowing. Feelings and mood are rarely dealt with except in rather off-handed remarks about intuitive leaps and creative encounters. Few consider what a model of inquiry based on mood and feeling might look like.…
Solving Rational Expectations Models Using Excel
ERIC Educational Resources Information Center
Strulik, Holger
2004-01-01
Simple problems of discrete-time optimal control can be solved using a standard spreadsheet software. The employed-solution method of backward iteration is intuitively understandable, does not require any programming skills, and is easy to implement so that it is suitable for classroom exercises with rational-expectations models. The author…
Macroeconomics after Two Decades of Rational Expectations.
ERIC Educational Resources Information Center
McCallum, Bennett T.
1994-01-01
Discusses real business cycle analysis, growth theory, and other economic concepts in the context of the rational expectations revolution in macroeconomics. Focuses on post-1982 research. Concludes that the rejuvenation of growth analysis is an encouraging development because it could lead to changes in welfare policy. (CFR)
Macroeconomics after Two Decades of Rational Expectations.
ERIC Educational Resources Information Center
McCallum, Bennett T.
1994-01-01
Discusses real business cycle analysis, growth theory, and other economic concepts in the context of the rational expectations revolution in macroeconomics. Focuses on post-1982 research. Concludes that the rejuvenation of growth analysis is an encouraging development because it could lead to changes in welfare policy. (CFR)
Rational Rhymes for Addressing Common Childhood Issues
ERIC Educational Resources Information Center
Warren, Jeffrey M.
2011-01-01
Music-based interventions are valuable tools counselors can use when working with children. Specific types of music-based interventions, such as songs or rhymes, can be especially pertinent in addressing the thoughts, feelings, and behaviors of children. Rational-emotive behavior therapy (REBT) provides a therapeutic framework that encourages…
Rational Emotive Behavior Therapy: Humanism in Action.
ERIC Educational Resources Information Center
Hill, Larry K.
1996-01-01
Claims that humanism, in both concept and philosophy, is encased in a literature that is predominantly abstract, making humanism difficult to translate into tangible day-to-day action. Argues that rational emotive behavior therapy (REBT), however, provides a detailed method for translating humanist concepts into humanist behavior. (RJM)
Disability and Rational Emotive Behavior Therapy (REBT).
ERIC Educational Resources Information Center
Gandy, Gerald L.
This article provides information on how Rational Emotive Behavior Therapy (REBT) can be adapted for use in rehabilitation counseling. It states that although clients with an average range of intelligence have responded well to REBT, clients with borderline intellectual functioning are not suitable candidates for cognitive disputing but can be…
Rational Emotive Behavior Therapy with Troubled Students.
ERIC Educational Resources Information Center
Zionts, Paul; Zionts, Laura
1997-01-01
Based on the early work of Albert Ellis, seeks to identify and challenge irrational beliefs that underlie behavior problems. Outlines concepts and methods of Rational Emotive Behavior Theory and describes the application both in counseling and as a mental health curriculum for troubled children and youth. Offers classroom techniques. (RJM)
Some Contemporary Rational Emotive Behavior Therapy Songs.
ERIC Educational Resources Information Center
Watts, Richard E.
1996-01-01
Presents several new rational emotive behavior therapy (REBT) songs. Claims that the songs may be used in both academic and therapeutic settings as a humorous way to address cognitive distortions or irrational beliefs. Reports that students and clients have responded favorably to these songs. (RJM)
Critical Thinking and Rational Emotive Behavior Therapy.
ERIC Educational Resources Information Center
Hatcher, Donald; Brown, Tony; Gariglietti, Kelli P.
2001-01-01
Notes limitations of Rational Emotive Behavior Therapy (REBT). Suggests that should these weaknesses be addressed, teachers of critical thinking would do well to incorporate REBT into their critical thinking courses. Relates that A. Ellis has suggested that the future of REBT is in integrating it into the educational curriculum as a way of…
Imitation in Infancy: Rational or Motor Resonance?
ERIC Educational Resources Information Center
Paulus, Markus; Hunnius, Sabine; Vissers, Marlies; Bekkering, Harold
2011-01-01
The present study investigates the contribution of 2 mechanisms to imitation in infancy. The principle of rational action suggests that infants normatively evaluate the efficiency of observed actions. In contrast, it has been proposed that motor resonance (i.e., the mapping of others' actions onto one's own motor repertoire) plays a central role…
Resource Allocation: Ration, Fashion, or Innovashun?
ERIC Educational Resources Information Center
Lourens, Roy
1986-01-01
Resource allocation is a key factor in promoting or retarding innovation. In a restrictive economic climate, it is easy to use resource allocation for decremental rationing and to stifle innovative thinking. The technique can also be used to ensure that the institution's human resources are encouraged to identify opportunities for innovation. (MSE)
Rational and Mechanistic Perspectives on Reinforcement Learning
ERIC Educational Resources Information Center
Chater, Nick
2009-01-01
This special issue describes important recent developments in applying reinforcement learning models to capture neural and cognitive function. But reinforcement learning, as a theoretical framework, can apply at two very different levels of description: "mechanistic" and "rational." Reinforcement learning is often viewed in mechanistic terms--as…
Does Rational Persuasion Influence Potential Consultees?
ERIC Educational Resources Information Center
Truscott, Stephen D.; Richardson, Robert D.; Cohen, Celina; Frank, Alicia; Palmeri, Deanna
2003-01-01
Success in collaborative school-based consultation depends on whether teachers implement interventions suggested by consultants. Rational Persuasion (RP) has been identified as one potentially effective way to influence consultee perceptions about proposed interventions. Investigates whether presenting RP importance and objections for behavioral…
Solving Rational Expectations Models Using Excel
ERIC Educational Resources Information Center
Strulik, Holger
2004-01-01
Simple problems of discrete-time optimal control can be solved using a standard spreadsheet software. The employed-solution method of backward iteration is intuitively understandable, does not require any programming skills, and is easy to implement so that it is suitable for classroom exercises with rational-expectations models. The author…
Resisting Consumerist Rationalities in Higher Vocational Education
ERIC Educational Resources Information Center
Puaca, Goran; Theandersson, Christer; Carlén, Margareta
2017-01-01
Swedish higher education policy is currently moving toward consumption ideals that focus on promoting the efficiency and economic viability of student choices. This paper scrutinizes students' practical considerations when making decisions regarding their education and future occupations and the choice rationalities and motives that these reflect.…
Reflections on Rational-Emotive Therapy.
ERIC Educational Resources Information Center
Ellis, Albert
1993-01-01
Reflects rational-emotive therapy (RET) in 1955 and discusses some of its recent constructivist and humanist theories and practice. Distinguishes between general RET, called synonymous with general cognitive-behavioral therapy, from preferential RET, called unique kind of cognitive therapy that partially overlaps with general cognitive-behavioral…
[Popper's critical rationalism and the biomedical sciences].
Havlícek, J
1993-11-08
Popper's rationalism makes an important contribution of the 20th century philosophy to the methodology of natural sciences. Through its criterion of falsification, it enabled the scientists to take a critical but constructive view on hypotheses, conjectures and theories. This attitude found its application also in medicine.
The Assessment of Rational Thinking: IQ ? RQ
ERIC Educational Resources Information Center
Stanovich, Keith E.; West, Richard F.
2014-01-01
In this article the authors argue that distinguishing between rationality and intelligence helps explain how people can be, at the same time, intelligent and irrational (Stanovich, 2009). As such, researchers need to study separately the individual differences in cognitive skills that underlie intelligence and the individual differences in…
Medicine, ethics and religion: rational or irrational?
Orr, R D; Genesen, L B
1998-12-01
Savulescu maintains that our paper, which encourages clinicians to honour requests for "inappropriate treatment" is prejudicial to his atheistic beliefs, and therefore wrong. In this paper we clarify and expand on our ideas, and respond to his assertion that medicine, ethics and atheism are objective, rational and true, while religion is irrational and false.
Suicide: rationality and responsibility for life.
Ho, Angela Onkay
2014-03-01
Death by suicide is widely held as an undesirable outcome. Most Western countries place emphasis on patient autonomy, a concept of controversy in relation to suicide. This paper explores the tensions between patients' rights and many societies' overarching desire to prevent suicide, while clarifying the relations between mental disorders, mental capacity, and rational suicide. A literature search was conducted using search terms of suicide and ethics in the PubMed and LexisNexis Academic databases. Article titles and abstracts were reviewed and deemed relevant if the paper addressed topics of rational suicide, patient autonomy or rights, or responsibility for life. Further articles were found from reference lists and by suggestion from preliminary reviewers of this paper. Suicidal behaviour in a person cannot be reliably predicted, yet various associations and organizations have developed standards of care for managing patients exhibiting suicidal behaviour. The responsibility for preventing suicide tends to be placed on the treating clinician. In cases where a person is capable of making treatment decisions--uninfluenced by any mental disorder--there is growing interest in the concept of rational suicide. There is much debate about whether suicide can ever be rational. Designating suicide as an undesirable event that should never occur raises the debate of who is responsible for one's life and runs the risk of erroneously attributing blame for suicide. While upholding patient rights of autonomy in psychiatric care is laudable, cases of suicidality warrant a delicate consideration of clinical judgment, duty of care, and legal obligations.
Reflections on Rational-Emotive Therapy.
ERIC Educational Resources Information Center
Ellis, Albert
1993-01-01
Reflects rational-emotive therapy (RET) in 1955 and discusses some of its recent constructivist and humanist theories and practice. Distinguishes between general RET, called synonymous with general cognitive-behavioral therapy, from preferential RET, called unique kind of cognitive therapy that partially overlaps with general cognitive-behavioral…
Rational Emotive Behavior Therapy with Troubled Students.
ERIC Educational Resources Information Center
Zionts, Paul; Zionts, Laura
1997-01-01
Based on the early work of Albert Ellis, seeks to identify and challenge irrational beliefs that underlie behavior problems. Outlines concepts and methods of Rational Emotive Behavior Theory and describes the application both in counseling and as a mental health curriculum for troubled children and youth. Offers classroom techniques. (RJM)
The Rational-Emotive Approach: A Critique
ERIC Educational Resources Information Center
Morris, G. Barry
1976-01-01
The critique of Rational-Emotive Therapy aims criticism at Ellis' concept of irrationality, analysis of human behavior and therapeutic techniques. Ellis suggests that his critic's claims lack the support of experimental evidence. He further suggests that an "existential" bias pervades which differs from his own brand of…
Evaluation of Australian Ration Packs. Revision of Combat Ration One Man,
1986-04-01
FOOD SCIENCE ESTABLISHMENT AFFSE REPORT 1/86 FIELD EVALUATION OF AUSTRALIAN RATION PACKS REVISION OF COMBAT RATION ONE MAN (U) C. H. FORBES-EWAN and D...individual items or in a packed form" (DOD, 1984). For group feeding, the first choice in both combat and non-combat situations is fresh food . This is...more brews?" (014): "In general. is there enough food in each ration pack ?" (0.27). Analysis of these questions was by Chi-square test. Additionally
Mapping optically variable quasars towards the Galactic plane
NASA Astrophysics Data System (ADS)
Fernandez-Trincado, J. G.; Verdugo, T.; Reylé, C.; Robin, A. C.; de Diego, J. A.; Motta, V.; Vega, L.; Downes, J. J.; Mateu, C.; Vivas, A. K.; Briceño, C.; Abad, C.; Vieira, K.; Hernández, J.; Nuñez, A.; Gatuzz, E.
2015-12-01
We present preliminary results of the CIDA Equatorial Variability Survey (CEVS), looking for quasar (hereafter QSO) candidates near the Galactic plane. The CEVS contains photometric data from extended and adjacent regions of the Milky Way disk (˜ 500 sq. deg.). In this work 2.5 square degrees with moderately high temporal sampling in the CEVS were analyzed. The selection of QSO candidates was based on the study of intrinsic optical photometric variability of 14,719 light curves. We studied samples defined by cuts in the variability index (V_{index}>66.5), periodicity index (Q > 2), and the distribution of these sources in the plane (A_T,γ), using a slight modification of the first-order of the structure function for the temporal sampling of the survey. Finally, 288 sources were selected as QSO candidates. The results shown in this work are a first attempt to develop a robust method to detect QSO towards the Galactic plane in the era of massive surveys such as VISTA and Gaia.
The UKIDSS Galactic Plane Survey
NASA Astrophysics Data System (ADS)
Lucas, P. W.; Hoare, M. G.; Longmore, A.; Schröder, A. C.; Davis, C. J.; Adamson, A.; Bandyopadhyay, R. M.; de Grijs, R.; Smith, M.; Gosling, A.; Mitchison, S.; Gáspár, A.; Coe, M.; Tamura, M.; Parker, Q.; Irwin, M.; Hambly, N.; Bryant, J.; Collins, R. S.; Cross, N.; Evans, D. W.; Gonzalez-Solares, E.; Hodgkin, S.; Lewis, J.; Read, M.; Riello, M.; Sutorius, E. T. W.; Lawrence, A.; Drew, J. E.; Dye, S.; Thompson, M. A.
2008-11-01
The UKIDSS Galactic Plane Survey (GPS) is one of the five near-infrared Public Legacy Surveys that are being undertaken by the UKIDSS consortium, using the Wide Field Camera on the United Kingdom Infrared Telescope. It is surveying 1868 deg2 of the northern and equatorial Galactic plane at Galactic latitudes -5° < b < 5° in the J, H and K filters and a ~200-deg2 area of the Taurus-Auriga-Perseus molecular cloud complex in these three filters and the 2.12 μm (1-0) H2 filter. It will provide data on ~2 × 109 sources. Here we describe the properties of the data set and provide a user's guide for its exploitation. We also present brief Demonstration Science results from DR2 and from the Science Verification programme. These results illustrate how GPS data will frequently be combined with data taken in other wavebands to produce scientific results. The Demonstration Science comprises six studies. (1) A GPS-Spitzer-GLIMPSE cross-match for the star formation region G28.983-0.603 to identify YSOs. This increases the number of YSOs identified by a factor of 10 compared to GLIMPSE alone. (2) A wide-field study of the M17 nebula, in which an extinction map of the field is presented and the effect of source confusion on luminosity functions in different subregions is noted. (3) H2 emission in the ρ Ophiuchi dark cloud. All the molecular jets are traced back to a single active clump containing only a few protostars, which suggests that the duration of strong jet activity and associated rapid accretion in low-mass protostars is brief. (4) X-ray sources in the nuclear bulge. The GPS data distinguishes local main-sequence counterparts with soft X-ray spectra from nuclear bulge giant counterparts with hard X-ray spectra. (5) External galaxies in the zone of avoidance. The galaxies are clearly distinguished from stars in fields at longitudes l > 90°. (6) IPHAS-GPS optical-infrared spectrophotometric typing. The (i' - J) versus (J - H) diagram is used to distinguish A-F type
Sagittal plane deformity: an overview of interpretation and management
Roussouly, Pierre
2010-01-01
The impact of sagittal plane alignment on the treatment of spinal disorders is of critical importance. A failure to recognise malalignment in this plane can have significant consequences for the patient not only in terms of pain and deformity, but also social interaction due to deficient forward gaze. A good understanding of the principles of sagittal balance is vital to achieve optimum outcomes when treating spinal disorders. Even when addressing problems in the coronal plane, an awareness of sagittal balance is necessary to avoid future complications. The normal spine has lordotic curves in the cephalad and caudal regions with a kyphotic curve in between. Overall, there is a positive correlation between thoracic kyphosis and lumbar lordosis. There are variations on the degree of normal curvature but nevertheless this shape allows equal distribution of forces across the spinal column. It is the disruption of this equilibrium by pathological processes or, as in most cases, ageing that results in deformity. This leads to adaptive changes in the pelvis and lower limbs. The effects of limb alignment on spinal posture are well documented. We now also know that changes in pelvic posture also affect spinal alignment. Sagittal malalignment presents as an exaggeration or deficiency of normal lordosis or kyphosis. Most cases seen in clinical practise are due to kyphotic deformity secondary to inflammatory, degenerative or post-traumatic disorders. They may also be secondary to infection or tumours. There is usually pain and functional disability along with concerns about self-image and social interaction due to inability to maintain a horizontal gaze. The resultant pelvic and lower limb posture is an attempt to restore normal alignment. Addressing this complex problem requires detailed expertise and awareness of the potential pitfalls surrounding its treatment. PMID:20567858
Sagittal plane deformity: an overview of interpretation and management.
Roussouly, Pierre; Nnadi, Colin
2010-11-01
The impact of sagittal plane alignment on the treatment of spinal disorders is of critical importance. A failure to recognise malalignment in this plane can have significant consequences for the patient not only in terms of pain and deformity, but also social interaction due to deficient forward gaze. A good understanding of the principles of sagittal balance is vital to achieve optimum outcomes when treating spinal disorders. Even when addressing problems in the coronal plane, an awareness of sagittal balance is necessary to avoid future complications. The normal spine has lordotic curves in the cephalad and caudal regions with a kyphotic curve in between. Overall, there is a positive correlation between thoracic kyphosis and lumbar lordosis. There are variations on the degree of normal curvature but nevertheless this shape allows equal distribution of forces across the spinal column. It is the disruption of this equilibrium by pathological processes or, as in most cases, ageing that results in deformity. This leads to adaptive changes in the pelvis and lower limbs. The effects of limb alignment on spinal posture are well documented. We now also know that changes in pelvic posture also affect spinal alignment. Sagittal malalignment presents as an exaggeration or deficiency of normal lordosis or kyphosis. Most cases seen in clinical practise are due to kyphotic deformity secondary to inflammatory, degenerative or post-traumatic disorders. They may also be secondary to infection or tumours. There is usually pain and functional disability along with concerns about self-image and social interaction due to inability to maintain a horizontal gaze. The resultant pelvic and lower limb posture is an attempt to restore normal alignment. Addressing this complex problem requires detailed expertise and awareness of the potential pitfalls surrounding its treatment.
Curve Boxplot: Generalization of Boxplot for Ensembles of Curves.
Mirzargar, Mahsa; Whitaker, Ross T; Kirby, Robert M
2014-12-01
In simulation science, computational scientists often study the behavior of their simulations by repeated solutions with variations in parameters and/or boundary values or initial conditions. Through such simulation ensembles, one can try to understand or quantify the variability or uncertainty in a solution as a function of the various inputs or model assumptions. In response to a growing interest in simulation ensembles, the visualization community has developed a suite of methods for allowing users to observe and understand the properties of these ensembles in an efficient and effective manner. An important aspect of visualizing simulations is the analysis of derived features, often represented as points, surfaces, or curves. In this paper, we present a novel, nonparametric method for summarizing ensembles of 2D and 3D curves. We propose an extension of a method from descriptive statistics, data depth, to curves. We also demonstrate a set of rendering and visualization strategies for showing rank statistics of an ensemble of curves, which is a generalization of traditional whisker plots or boxplots to multidimensional curves. Results are presented for applications in neuroimaging, hurricane forecasting and fluid dynamics.
Mathematical definition of the curve of Spee in permanent healthy dentitions in man.
Ferrario, V F; Sforza, C; Miani, A; Colombo, A; Tartaglia, G
1992-09-01
The intrinsic morphology of the mandibular curve of Spee (i.e. independent from reference planes) was studied in 50 men and 45 women with sound dentitions. Left and right curves were reconstructed by a second-order quadratic interpolation of buccal cusp tips. Gender differences were found in both sides, while side differences were found only in the male sample. Male and female curves had similar concavities, but the position of the interpolating second-order quadratic curve relative to the dental arch was significantly different. The right and left male sides showed different concavities, the right-hand side being flatter than the left. Male curves appeared larger than female ones, and the left-hand side was significantly larger than the right regardless of gender. The reported second-order quadratic curves could be used as reference for prosthetic and orthodontic reconstructions.
Galactic plane gamma-radiation
NASA Technical Reports Server (NTRS)
Hartman, R. C.; Kniffen, D. A.; Thompson, D. J.; Fichtel, C. E.; Ogelman, H. B.; Tumer, T.; Ozel, M. E.
1979-01-01
Analysis of the SAS 2 data together with the COS B results shows that the distribution of galactic gamma-radiation has several similarities to that of other large-scale tracers of galactic structure. The radiation is primarily confined to a thin disc which exhibits offsets from b = 0 degrees similar to warping at radio frequencies. The principal distinction of the gamma-radiation is a stronger contrast in intensity between the region from 310 to 45 degrees in longitude and the regions away from the center that can be attributed to a variation in cosmic-ray density as a function of position in Galaxy. The diffuse galactic gamma-ray energy spectrum shows no significant variation in direction, and the spectrum seen along the plane is the same as that for the galactic component of the gamma-radiation at high altitudes. The uniformity of the galactic gamma-ray spectrum, the smooth decrease in intensity as a function of altitude, and the absence of any galactic gamma-ray sources at high altitudes indicate a diffuse origin for bulk of the galactic gamma-radiation rather than a collection of localized sources.
On plane submerged laminar jets
NASA Astrophysics Data System (ADS)
Coenen, Wilfried; Sanchez, Antonio L.
2016-11-01
We address the laminar flow generated when a developed stream of liquid of kinematic viscosity ν flowing along channel of width 2 h discharges into an open space bounded by two symmetric plane walls departing from the channel rim with an angle α 1 . Attention is focused on values of the jet volume flux 2 Q such that the associated Reynolds number Re = Qh / ν is of order unity. The formulation requires specification of the boundary conditions far from the channel exit. If the flow is driven by the volume flux, then the far-field solution corresponds to Jeffery-Hamel self-similar flow. However, as noted by Fraenkel (1962), such solutions exist only for α <129o in a limited range of Reynolds numbers 0 <=Re <=Rec (α) (e.g. Rec = 1 . 43 for α = π / 2). It is reasoned that an alternative solution, driven by a fraction of the momentum flux of the feed stream, may also exist for all values of Re and α, including a near-centerline Bickley jet, a surrounding Taylor potential flow driven by the jet entrainment, and a Falkner-Skan near-wall boundary layer. Numerical integrations of the Navier-Stokes equations are used to ascertain the existence of these different solutions.
Radioactivity in the galactic plane
NASA Technical Reports Server (NTRS)
Walraven, G. D.; Haymes, R. C.
1976-01-01
The paper reports the detection of a large concentration of interstellar radioactivity during balloon-altitude measurements of gamma-ray energy spectra in the band between 0.02 and 12.27 MeV from galactic and extragalactic sources. Enhanced counting rates were observed in three directions towards the plane of the Galaxy; a power-law energy spectrum is computed for one of these directions (designated B 10). A large statistical deviation from the power law in a 1.0-FWHM interval centered near 1.16 MeV is discussed, and the existence of a nuclear gamma-ray line at 1.15 MeV in B 10 is postulated. It is suggested that Ca-44, which emits gamma radiation at 1.156 MeV following the decay of radioactive Sc-44, is a likely candidate for this line, noting that Sc-44 arises from Ti-44 according to explosive models of supernova nucleosynthesis. The 1.16-MeV line flux inferred from the present data is shown to equal the predicted flux for a supernova at a distance of approximately 3 kpc and an age not exceeding about 100 years.
Duel-Plane Optical Disdrometer
NASA Astrophysics Data System (ADS)
Winsky, B. E.; Eichinger, W. E.
2011-12-01
Acquiring better drop-size distributions of rainfall will improve our understanding of the spatial and temporal variability of rainfall. In order to fully capture the spatial and temporal variability of rainfall, a robust, calibration free, low-cost instrument that provides an accurate drop-size distribution is required. Therefore, The University of Iowa Lidar Group has developed and built a new duel-plane optical disdrometer that meets these criteria. Two sheets of laser light, vertically spaced by 1 cm are produced by two 670nm laser beams passing through a collecting lens and culminating lens, respectively. The two sheets of laser light then pass through a convex lens located 20 cm from the lasers that focuses the light on a photo detector. A computer reads in and stores the voltages at 10 kHz. The velocity, diameter, shape and drop-size distribution of raindrops are extracted from the voltage measurements. Rainfall data collected in Iowa City, IA tested our disdrometer's robustness and accuracy of providing drop-size distributions. Our distrometer is advantageous because it is simple, low-cost, and requires no calibration.
Optimal vibration control of curved beams using distributed parameter models
NASA Astrophysics Data System (ADS)
Liu, Fushou; Jin, Dongping; Wen, Hao
2016-12-01
The design of linear quadratic optimal controller using spectral factorization method is studied for vibration suppression of curved beam structures modeled as distributed parameter models. The equations of motion for active control of the in-plane vibration of a curved beam are developed firstly considering its shear deformation and rotary inertia, and then the state space model of the curved beam is established directly using the partial differential equations of motion. The functional gains for the distributed parameter model of curved beam are calculated by extending the spectral factorization method. Moreover, the response of the closed-loop control system is derived explicitly in frequency domain. Finally, the suppression of the vibration at the free end of a cantilevered curved beam by point control moment is studied through numerical case studies, in which the benefit of the presented method is shown by comparison with a constant gain velocity feedback control law, and the performance of the presented method on avoidance of control spillover is demonstrated.
Characterizing time series via complexity-entropy curves
NASA Astrophysics Data System (ADS)
Ribeiro, Haroldo V.; Jauregui, Max; Zunino, Luciano; Lenzi, Ervin K.
2017-06-01
The search for patterns in time series is a very common task when dealing with complex systems. This is usually accomplished by employing a complexity measure such as entropies and fractal dimensions. However, such measures usually only capture a single aspect of the system dynamics. Here, we propose a family of complexity measures for time series based on a generalization of the complexity-entropy causality plane. By replacing the Shannon entropy by a monoparametric entropy (Tsallis q entropy) and after considering the proper generalization of the statistical complexity (q complexity), we build up a parametric curve (the q -complexity-entropy curve) that is used for characterizing and classifying time series. Based on simple exact results and numerical simulations of stochastic processes, we show that these curves can distinguish among different long-range, short-range, and oscillating correlated behaviors. Also, we verify that simulated chaotic and stochastic time series can be distinguished based on whether these curves are open or closed. We further test this technique in experimental scenarios related to chaotic laser intensity, stock price, sunspot, and geomagnetic dynamics, confirming its usefulness. Finally, we prove that these curves enhance the automatic classification of time series with long-range correlations and interbeat intervals of healthy subjects and patients with heart disease.
Characterizing time series via complexity-entropy curves.
Ribeiro, Haroldo V; Jauregui, Max; Zunino, Luciano; Lenzi, Ervin K
2017-06-01
The search for patterns in time series is a very common task when dealing with complex systems. This is usually accomplished by employing a complexity measure such as entropies and fractal dimensions. However, such measures usually only capture a single aspect of the system dynamics. Here, we propose a family of complexity measures for time series based on a generalization of the complexity-entropy causality plane. By replacing the Shannon entropy by a monoparametric entropy (Tsallis q entropy) and after considering the proper generalization of the statistical complexity (q complexity), we build up a parametric curve (the q-complexity-entropy curve) that is used for characterizing and classifying time series. Based on simple exact results and numerical simulations of stochastic processes, we show that these curves can distinguish among different long-range, short-range, and oscillating correlated behaviors. Also, we verify that simulated chaotic and stochastic time series can be distinguished based on whether these curves are open or closed. We further test this technique in experimental scenarios related to chaotic laser intensity, stock price, sunspot, and geomagnetic dynamics, confirming its usefulness. Finally, we prove that these curves enhance the automatic classification of time series with long-range correlations and interbeat intervals of healthy subjects and patients with heart disease.
The challenge of highly curved monolithic imaging detectors
NASA Astrophysics Data System (ADS)
Iwert, Olaf; Delabre, Bernard
2010-07-01
In a recent optical design study of CODEX - a visible spectrograph planned for the European Extremely Large Telescope (E-ELT) - it was determined that a significant simplification of the optical design - accompanied by an improvement of the image quality - could be achieved through the application of large format (90mm square) concave spherically curved detectors with a low radius of curvature (500 to 250mm). Current assemblies of image sensors and optics rely on the optics to project a corrected image onto a flat detector. While scientific large-size CCDs (49mm square) have been produced unintentionally with a spherical radius of convex curvature of around 5m, in the past most efforts have concentrated onto flattening the light-sensitive detector silicon area as best as possible for both scientific state-of-the-art systems, as well as commercial low-cost consumer products. In some cases curved focal planes are mosaicked out of individual flat detectors, but a standard method to derive individual spherically curved large size detectors has not been demonstrated. This paper summarizes important developments in the area of curved detectors in the past and their different technical approaches mostly linked to specific thinning processes. ESO's specifications for an ongoing feasibility study are presented. First results of the latter are described with a link to theoretical and practical examinations of currently available technology to implement curved CCD and CMOS detectors for scientific applications.
Theory and experiments on Peano and Hilbert curve RFID tags
NASA Astrophysics Data System (ADS)
McVay, John; Hoorfar, Ahmad; Engheta, Nader
2006-05-01
Recently, there has been considerable interest in the area of Radio Frequency Identification (RFID) and Radio Frequency Tagging (RFTAG). This emerging area of interest can be applied for inventory control (commercial) as well as friend/foe identification (military) to name but a few. The current technology can be broken down into two main groups, namely passive and active RFID tags. Utilization of Space-Filling Curve (SFC) geometries, such as the Peano and Hilbert curves, has been recently investigated for use in completely passive RFID applications [1, 2]. In this work, we give an overview of our work on the space-filling curves and the potential for utilizing the electrically small, resonant characteristics of these curves for use in RFID technologies with an emphasis on the challenging issues involved when attempting to tag conductive objects. In particular, we investigate the possible use of these tags in conjunction with high impedance ground-planes made of Hilbert or Peano curve inclusions [3, 4] to develop electrically small RFID tags that may also radiate efficiently, within close proximity of large conductive objects [5].
Computation and inversion of ion spectra for neutron depth profiling of curved surfaces
NASA Astrophysics Data System (ADS)
Shultis, J. Kenneth
2004-07-01
Neutron depth profiling (NDP) is a nondestructive technique for determining the concentration of special isotopes within several microns of a sample's surface. Previous NDP analyses, however, have been restricted to samples with plane surfaces. Here samples with curved surfaces are considered. In particular, a method for estimating the energy spectrum of ions emitted from curved surfaces is presented. Also, a robust method for inverting the NDP ion energy spectra is presented that yields accurate concentration profiles for both under- and overdetermined NDP spectra.
The Ethics and Reality of Rationing in Medicine
Scheunemann, Leslie P.
2011-01-01
Rationing is the allocation of scarce resources, which in health care necessarily entails withholding potentially beneficial treatments from some individuals. Rationing is unavoidable because need is limitless and resources are not. How rationing occurs is important because it not only affects individual lives but also expresses society’s most important values. This article discusses the following topics: (1) the inevitability of rationing of social goods, including medical care; (2) types of rationing; (3) ethical principles and procedures for fair allocation; and (4) whether rationing ICU care to those near the end of life would result in substantial cost savings. PMID:22147821
Three-dimensional broadband ground-plane cloak made of metamaterials.
Ma, Hui Feng; Cui, Tie Jun
2010-06-01
Since invisibility cloaks were first suggested by transformation optics theory, there has been much work on the theoretical analysis and design of various types and a few experimental verifications at microwave and optical frequencies within two-dimensional limits. Here, we realize the first practical implementation of a fully 3D broadband and low-loss ground-plane cloak at microwave frequencies. The cloak, realized by drilling inhomogeneous holes in multi-layered dielectric plates, can conceal a 3D object located under a curved conducting plane from all viewing angles by imitating the reflection of a flat conducting plane. We also designed and realized, using non-resonant metamaterials, a high-gain lens antenna that can produce narrow-beam plane waves in the near-field region in a broad frequency band. The antenna constitutes the transmitter of the measurement system and is essential for the measurement of cloaking behaviour.
Three-dimensional broadband ground-plane cloak made of metamaterials
Ma, Hui Feng; Cui, Tie Jun
2010-01-01
Since invisibility cloaks were first suggested by transformation optics theory, there has been much work on the theoretical analysis and design of various types and a few experimental verifications at microwave and optical frequencies within two-dimensional limits. Here, we realize the first practical implementation of a fully 3D broadband and low-loss ground-plane cloak at microwave frequencies. The cloak, realized by drilling inhomogeneous holes in multi-layered dielectric plates, can conceal a 3D object located under a curved conducting plane from all viewing angles by imitating the reflection of a flat conducting plane. We also designed and realized, using non-resonant metamaterials, a high-gain lens antenna that can produce narrow-beam plane waves in the near-field region in a broad frequency band. The antenna constitutes the transmitter of the measurement system and is essential for the measurement of cloaking behaviour. PMID:20975696
Towards Dualband Megapixel QWIP Focal Plane Arrays
2006-01-01
Journal Article PREPRINT 3. DATES COVERED (From - To) 2006 4. TITLE AND SUBTITLE Towards dualband megapixel QWIP focal plane arrays (PREPRINT) 5a...pixel quantum well infrared photodetector ( QWIP ) focal planes have been demonstrated with excellent imaging performance. The MWIR QWIP detector array...registered simultaneously readable dualband QWIP focal plane arrays. In this paper, we will discuss the performance in terms of quantum efficiency
RF/Optical Demonstration: Focal Plane Assembly
NASA Astrophysics Data System (ADS)
Hoppe, D. J.; Chung, S.; Kovalik, J.; Gama, E.; Fernandez, M. M.
2016-11-01
In this article, we describe the second-generation focal plane optical assembly employed in the RF/optical demonstration at DSS-13. This assembly receives reflected light from the two mirror segments mounted on the RF primary. The focal plane assembly contains a fast steering mirror (FSM) to stabilize the focal plane spot, a pupil camera to aid in aligning the two segments, and several additional cameras for receiving the optical signal prior to as well as after the FSM loop.
Cochlear microphonic broad tuning curves
NASA Astrophysics Data System (ADS)
Ayat, Mohammad; Teal, Paul D.; Searchfield, Grant D.; Razali, Najwani
2015-12-01
It is known that the cochlear microphonic voltage exhibits much broader tuning than does the basilar membrane motion. The most commonly used explanation for this is that when an electrode is inserted at a particular point inside the scala media, the microphonic potentials of neighbouring hair cells have different phases, leading to cancelation at the electrodes location. In situ recording of functioning outer hair cells (OHCs) for investigating this hypothesis is exceptionally difficult. Therefore, to investigate the discrepancy between the tuning curves of the basilar membrane and those of the cochlear microphonic, and the effect of phase cancellation of adjacent hair cells on the broadness of the cochlear microphonic tuning curves, we use an electromechanical model of the cochlea to devise an experiment. We explore the effect of adjacent hair cells (i.e., longitudinal phase cancellation) on the broadness of the cochlear microphonic tuning curves in different locations. The results of the experiment indicate that active longitudinal coupling (i.e., coupling with active adjacent outer hair cells) only slightly changes the broadness of the CM tuning curves. The results also demonstrate that there is a π phase difference between the potentials produced by the hair bundle and the soma near the place associated with the characteristic frequency based on place-frequency maps (i.e., the best place). We suggest that the transversal phase cancellation (caused by the phase difference between the hair bundle and the soma) plays a far more important role than longitudinal phase cancellation in the broadness of the cochlear microphonic tuning curves. Moreover, by increasing the modelled longitudinal resistance resulting the cochlear microphonic curves exhibiting sharper tuning. The results of the simulations suggest that the passive network of the organ of Corti determines the phase difference between the hair bundle and soma, and hence determines the sharpness of the
Real-time defect detection on highly reflective curved surfaces
NASA Astrophysics Data System (ADS)
Rosati, G.; Boschetti, G.; Biondi, A.; Rossi, A.
2009-03-01
This paper presents an automated defect detection system for coated plastic components for the automotive industry. This research activity came up as an evolution of a previous study which employed a non-flat mirror to illuminate and inspect high reflective curved surfaces. According to this method, the rays emitted from a light source are conveyed on the surface under investigation by means of a suitably curved mirror. After the reflection on the surface, the light rays are collected by a CCD camera, in which the coating defects appear as shadows of various shapes and dimensions. In this paper we present an evolution of the above-mentioned method, introducing a simplified mirror set-up in order to reduce the costs and the complexity of the defect detection system. In fact, a set of plane mirrors is employed instead of the curved one. Moreover, the inspection of multiple bend radius parts is investigated. A prototype of the machine vision system has been developed in order to test this simplified method. This device is made up of a light projector, a set of plane mirrors for light rays reflection, a conveyor belt for handling components, a CCD camera and a desktop PC which performs image acquisition and processing. Like in the previous system, the defects are identified as shadows inside a high brightness image. At the end of the paper, first experimental results are presented.
Rational Choice and Developmental Influences on Recidivism Among Adolescent Felony Offenders
Fagan, Jeffrey; Piquero, Alex R.
2009-01-01
Recent case law and social science both have claimed that the developmental limitations of adolescents affect their capacity for control and decision making with respect to crime, diminishing their culpability and reducing their exposure to punishment. Social science has focused on two concurrent adolescent developmental influences: the internalization of legal rules and norms that regulate social and antisocial behaviors, and the development of rationality to frame behavioral choices and decisions. The interaction of these two developmental processes, and the identification of one domain of socialization and development as the primary source of motivation or restraint in adolescence, is the focus of this article. Accordingly, we combine rational choice and legal socialization frameworks into an integrated, developmental model of criminality. We test this framework in a large sample of adolescent felony offenders who have been interviewed at six-month intervals for two years. Using hierarchical and growth curve models, we show that both legal socialization and rational choice factors influence patterns of criminal offending over time. When punishment risks and costs are salient, crime rates are lower over time. We show that procedural justice is a significant antecedent of legal socialization, but not of rational choice. We also show that both mental health and developmental maturity moderate the effects of perceived crime risks and costs on criminal offending. PMID:20148123
Digital scanner infrared focal plane technology
NASA Astrophysics Data System (ADS)
Ortiz, M. A.; Malone, N. R.; Harris, M.; Shin, J.; Byers, S.; Price, D.; Vampola, J.
2011-09-01
Advancements in finer geometry and technology advancements in circuit design now allow placement of digital architecture on cryogenic focal planes while using less power than heritage analog designs. These advances in technology reduce the size, weight, and power of modern focal planes. In addition, the interface to the focal plane is significantly simplified and is more immune to Electromagnetic Interference (EMI). The cost of the customer's instrument after integration with the digital scanning Focal Plane Array (FPA) has been significantly reduced by placing digital architecture such as Analog to digital convertors and Low Voltage Differential Signaling (LVDS) Inputs and Outputs (I/O) on the Read Out Integrated Circuit (ROIC).
Nanostructured carbon films with oriented graphitic planes
Teo, E. H. T.; Kalish, R.; Kulik, J.; Kauffmann, Y.; Lifshitz, Y.
2011-03-21
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.
L_p Extensions of Gonchar's Inequality for Rational Functions
NASA Astrophysics Data System (ADS)
Levin, A. L.; Saff, E. B.
1993-02-01
Given a condenser (E,\\, F) in the complex plane, let C(E,\\, F) denote its capacity and let \\mu^*=\\mu_E^*-\\mu_F^* be the (signed) equilibrium distribution for (E,\\, F). Given a finite positive measure \\mu on E\\cup F, let G(\\mu_E')=\\exp\\big(\\int\\log(d\\mu/d\\mu_E^*)\\,d\\mu_E^*\\big) and G(\\mu_F')=\\exp\\big(\\int\\log(d\\mu/d\\mu_F^*)\\,d\\mu_F^*\\big). We show that for 0 and for any rational function r_n of order n \\displaystyle \\Vert r_n\\Vert _{L_p(d\\mu,\\,E)}\\Vert 1/r_n\\Vert _{L_q(d\\mu,\\,F)}\\geq e^{-n/C(E,\\,F)}G^{1/p}(\\mu_E')G^{1/q}(\\mu_F'),(*)which extends a classical result due to A. A. Gonchar. For a symmetric condenser we also obtain a sharp lower bound for \\Vert r_n-\\lambda\\Vert _{L_p(d\\mu,\\,E\\cup F)}, where \\lambda=\\lambda(z) is equal to 0 on E and 1 on F. The question of exactness of (*) and the relation to certain n-widths are also discussed.Bibliography: 16 titles.
Relative Locality in Curved Spacetime
NASA Astrophysics Data System (ADS)
Kowalski-Glikman, Jerzy; Rosati, Giacomo
2013-07-01
In this paper we construct the action describing dynamics of the particle moving in curved spacetime, with a nontrivial momentum space geometry. Curved momentum space is the core feature of theories where relative locality effects are present. So far aspects of nonlinearities in momentum space have been studied only for flat or constantly expanding (de Sitter) spacetimes, relying on their maximally symmetric nature. The extension of curved momentum space frameworks to arbitrary spacetime geometries could be relevant for the opportunities to test Planck-scale curvature/deformation of particles momentum space. As a first example of this construction we describe the particle with κ-Poincaré momentum space on a circular orbit in Schwarzschild spacetime, where the contributes of momentum space curvature turn out to be negligible. The analysis of this problem relies crucially on the solution of the soccer ball problem.
Phase nucleation in curved space
NASA Astrophysics Data System (ADS)
Gómez, Leopoldo; García, Nicolás; Vitelli, Vincenzo; Lorenzana, José; Daniel, Vega
Nucleation and growth is the dominant relaxation mechanism driving first-order phase transitions. In two-dimensional flat systems, nucleation has been applied to a wide range of problems in physics, chemistry and biology. Here we study nucleation and growth of two-dimensional phases lying on curved surfaces and show that curvature modifies both critical sizes of nuclei and paths towards the equilibrium phase. In curved space, nucleation and growth becomes inherently inhomogeneous and critical nuclei form faster on regions of positive Gaussian curvature. Substrates of varying shape display complex energy landscapes with several geometry-induced local minima, where initially propagating nuclei become stabilized and trapped by the underlying curvature (Gómez, L. R. et al. Phase nucleation in curved space. Nat. Commun. 6:6856 doi: 10.1038/ncomms7856 (2015).).
Supply curves of conserved energy
NASA Astrophysics Data System (ADS)
Meier, A. K.
1982-05-01
Supply curves of conserved energy provide an accounting framework that expresses the potential for energy conservation. The economic worthiness of a conservation measure is expressed in terms of the cost of conserved energy, and a measure is considered economical when the cost of conserved energy is less than the price of the energy it replaces. A supply curve of conserved energy is independent of energy prices; however, the economical reserves of conserved energy will depend on energy prices. Double-counting of energy savings and error propagation are common problems when estimating conservation potentials, but supply curves minimize these difficulties and make their consequences predictable. The sensitivity of the cost of conserved energy is examined, as are variations in the optimal investment strategy in response to changes in inputs. Guidelines are presented for predicting the consequences of such changes.
Flow instability in a curved duct of rectangular cross section
NASA Astrophysics Data System (ADS)
Belaidi, A.; Johnson, M. W.; Humphrey, J. A. C.
1992-12-01
An experimental investigation has been carried out in a curved duct of rectangular cross section in order to study the development of flow instability in such geometries. Hot wire anemometry was used to obtain detailed measurements of velocity on the symmetry plane of the duct for different curvature ratios. As the duct Dean number is increased, a centrifugal instability develops and the Dean vortices are seen to oscillate along the inner wall. To understand the contribution of these vortices to the laminar-turbulent transition, time histories and spectra of the flow were taken on the symmetry plane of the duct for different Reynolds numbers. These data reveal a time-periodic motion along the inner wall where the secondary flows originating from the side wall boundary layers collide. The bend angle where this instability develops depends on the Reynolds number while the frequency of the instability depends on the curvature ratio of the bend.
Curve Fit Technique for a Smooth Curve Using Gaussian Sections.
1983-08-01
curve-fitting. Furthermore, the algorithm that does the fitting is simple enough to be used on a programmable calculator . 8 -I.F , A X i 4. Y-14 .4. - -* F.J OR;r IF 17 r*~~ , ac ~J ’a vt. . S ~ :.. *~All, a-4k .16’.- a1 1, t
Competency to Proceed to Trial Evaluations and Rational Understanding.
Ragatz, Laurie; Vitacco, Michael J; Tross, Rozanna
2015-12-01
In Dusky v. United States, the United States Supreme Court established "rational understanding" as a necessary component of a defendant's competency to stand trial. Yet, rational understanding has engendered misunderstanding, stemming from inconsistent court rulings and lack of systematic attention given to definitions of rationality. The purpose of this article is to assist with the conceptualization of rational understanding as it relates to competency to proceed to trial. This will be accomplished through a review of legal decisions and scholarly papers that provide various definitions of rationality. We discuss the suitability of standardized instruments of competency and how they may assist in providing a valid metric for evaluating rational abilities. We also provide discussion of how case law, in conjunction with psycholegal research, can be used to gain nuanced insight into operationalizations of rational understanding. By gaining a thorough understanding of rationality in competency to proceed to trial evaluations, clinicians may improve on the quality and foundation of their evaluations.
The Continuing Quest for Rationality in Curriculum Practice.
ERIC Educational Resources Information Center
Gay, Geneva
1979-01-01
Suggests that understanding different conceptual models of curriculum making will increase the effectiveness and rationality of the development process. Presents four commonly used models of curriculum development: empiricism, rationalism, pragmatism, and humanism. (Author/JM)
Effects of Nano- and Microscale SiO2 Masks on the Growth of a-Plane GaN Layers on r-Plane Sapphire
NASA Astrophysics Data System (ADS)
Son, Ji-Su; Miao, Cao; Honda, Yoshio; Yamaguchi, Masahito; Amano, Hiroshi; Seo, Yong Gon; Hwang, Sung-Min; Baik, Kwang Hyeon
2013-08-01
We report on the combined effects of a-plane GaN layers on a nanoscale patterned insulator on an r-plane sapphire substrate and epitaxial lateral overgrowth (ELOG) techniques. The fully coalescent a-plane GaN layer using nano- and microscale SiO2 masks showed the formation of nano- and microscale voids on the masks, respectively. Atomic force microscopy (AFM) measurements revealed a surface roughness of 0.63 nm and a submicron pit density of ˜7.8 ×107 cm-2. Photoluminescence (PL) intensity was enhanced by a factor of 9.0 in comparison with that of a planar sample. Omega full-width at half-maximum (FWHM) values of the (11bar 20) X-ray rocking curve along the c- and m-axes were 553 and 788 arcsec, respectively. A plan-view cathodoluminescence (CL) mapping image showed high luminescence intensity on the SiO2 masks.
Active particles on curved surfaces
NASA Astrophysics Data System (ADS)
Fily, Yaouen; Baskaran, Aparna; Hagan, Michael
Active systems have proved to be very sensitive to the geometry of their environment. This is often achieved by spending significant time at the boundary, probing its shape by gliding along it. I will discuss coarse graining the microscopic dynamics of self-propelled particles on a general curved surface to predict the way the density profile on the surface depends on its geometry. Beyond confined active particles, this formalism is a natural starting point to study objects that cannot leave the boundary at all, such as cells crawling on a curved substrate, animals running on uneven ground, or active colloids trapped at an interface.
Harmonic Measure of Critical Curves
Bettelheim, E.; Rushkin, I.; Gruzberg, I.A.; Wiegmann, P.
2005-10-21
Fractal geometry of critical curves appearing in 2D critical systems is characterized by their harmonic measure. For systems described by conformal field theories with central charge c{<=}1, scaling exponents of the harmonic measure have been computed by Duplantier [Phys. Rev. Lett. 84, 1363 (2000)] by relating the problem to boundary two-dimensional gravity. We present a simple argument connecting the harmonic measure of critical curves to operators obtained by fusion of primary fields and compute characteristics of the fractal geometry by means of regular methods of conformal field theory. The method is not limited to theories with c{<=}1.
Shock detachment from curved wedges
NASA Astrophysics Data System (ADS)
Mölder, S.
2017-03-01
Curved shock theory is used to show that the flow behind attached shocks on doubly curved wedges can have either positive or negative post-shock pressure gradients depending on the freestream Mach number, the wedge angle and the two wedge curvatures. Given enough wedge length, the flow near the leading edge can choke to force the shock to detach from the wedge. This local choking can preempt both the maximum deflection and the sonic criteria for shock detachment. Analytical predictions for detachment by local choking are supported by CFD results.
Shock detachment from curved wedges
NASA Astrophysics Data System (ADS)
Mölder, S.
2017-09-01
Curved shock theory is used to show that the flow behind attached shocks on doubly curved wedges can have either positive or negative post-shock pressure gradients depending on the freestream Mach number, the wedge angle and the two wedge curvatures. Given enough wedge length, the flow near the leading edge can choke to force the shock to detach from the wedge. This local choking can preempt both the maximum deflection and the sonic criteria for shock detachment. Analytical predictions for detachment by local choking are supported by CFD results.
Imitation in infancy: rational or motor resonance?
Paulus, Markus; Hunnius, Sabine; Vissers, Marlies; Bekkering, Harold
2011-01-01
The present study investigates the contribution of 2 mechanisms to imitation in infancy. The principle of rational action suggests that infants normatively evaluate the efficiency of observed actions. In contrast, it has been proposed that motor resonance (i.e., the mapping of others' actions onto one's own motor repertoire) plays a central role in imitation. This study tested 14-month-old infants (n = 95) in 5 conditions and manipulated the extent to which the observed actions could be matched onto the infants' own motor repertoire as well as whether the observed behavior appeared to be efficient. The results suggest that motor resonance plays a more central role in imitation in infancy than does a rational evaluation of the observed action.
Moral Credentialing and the Rationalization of Misconduct
Brown, Ryan P.; Tamborski, Michael; Wang, Xiaoqian; Barnes, Collin D.; Mumford, Michael D.; Connelly, Shane; Devenport, Lynn D.
2010-01-01
Recent studies lead to the paradoxical conclusion that the act of affirming one’s egalitarian or pro-social values and virtues might subsequently facilitate prejudiced or self-serving behavior, an effect previously referred to as “moral credentialing.” The present study extends this paradox to the domain of academic misconduct and investigates the hypothesis that such an effect might be limited by the extent to which misbehavior is rationalizable. Using a paradigm designed to investigate deliberative and rationalized forms of cheating (von Hippel, Lakin, & Shakarchi, 2005), we found that when participants had credentialed themselves (versus a non-close acquaintance) via a set of hypothetical moral dilemmas, they were more likely to cheat on a subsequent math task, but only if cheating was highly rationalizable. When cheating was difficult to rationalize, moral credentialing had almost no impact on cheating. PMID:21503267
Vaccines: From Empirical Development to Rational Design
Rueckert, Christine; Guzmán, Carlos A.
2012-01-01
Infectious diseases are responsible for an overwhelming number of deaths worldwide and their clinical management is often hampered by the emergence of multi-drug-resistant strains. Therefore, prevention through vaccination currently represents the best course of action to combat them. However, immune escape and evasion by pathogens often render vaccine development difficult. Furthermore, most currently available vaccines were empirically designed. In this review, we discuss why rational design of vaccines is not only desirable but also necessary. We introduce recent developments towards specifically tailored antigens, adjuvants, and delivery systems, and discuss the methodological gaps and lack of knowledge still hampering true rational vaccine design. Finally, we address the potential and limitations of different strategies and technologies for advancing vaccine development. PMID:23144616
Rationally designed multitarget anti-HIV agents.
Zhan, P; Liu, X
2013-01-01
Multitarget-directed ligands (MTDLs), an emerging and appealing drug discovery strategy, utilizing a single chemical entity to inhibit multitargets, was confirmed to be effective in reducing the likelihood of drug resistance, diminishing problems of dosing complexity, drug-drug interactions and toxicities, as well as improving patient compliance. The exploration of MTDL strategy should be valuable in anti-HIV drug discovery. In this article, current knowledge and strategies for the rational design of the multitarget and selective anti-HIV agents are described and a number of illustrative examples are given. Moreover, the challenges, limitations and outlook of such novel drug design strategies are also presented, with a goal to highlight the representative paradigms in the rational design of MTDLs, and to help medicinal chemists discover the next generation of multitarget anti-HIV agents.
The origin of bounded rationality and intelligence.
Lo, Andrew W
2013-09-01
Rational economic behavior in which individuals maximize their own self-interest is only one of many possible types of behavior that arise from natural selection. Given an initial population of individuals, each assigned a purely arbitrary behavior with respect to a binary choice problem, and assuming that offspring behave identically to their parents, only those behaviors linked to reproductive success will survive, and less successful behaviors will disappear exponentially fast. This framework yields a single evolutionary explanation for the origin of several behaviors that have been observed in organisms ranging from bacteria to humans, including risk-sensitive foraging, risk aversion, loss aversion, probability matching, randomization, and diversification. The key to understanding which types of behavior are more likely to survive is how behavior affects reproductive success in a given population's environment. From this perspective, intelligence is naturally defined as behavior that increases the likelihood of reproductive success, and bounds on rationality are determined by physiological and environmental constraints.
Rationally Irrational: The Case of Sexual Burglary.
Pedneault, Amelie; Beauregard, Eric; Harris, Danielle A; Knight, Raymond A
2015-08-01
The present study investigated rationality in sexually motivated burglaries. Specifically, we analyzed the situational cues identified by sexual burglars in their target selection. The research project investigated 224 individual incidents of residential burglary with apparent sexual motivations. Situational characteristics of the incidents were recorded and analyzed using forward sequential regressions. Results indicated that most sexually motivated burglaries occurred in occupied residences with deficient physical guardianship, when the victim was alone. Violence, theft, penetration, and fetishism were found to be committed in circumstances that increased the benefits and lowered the risks. Results showed that sexual burglary is rational in nature-sexual burglars chose residences that were easy to break into. We found little support for the premise that such opportunities arose while carrying out regular burglaries. Instead, the data indicated that sexual burglars acted opportunistically on situational cues that are markedly dissimilar to those of regular burglars.
Probability judgments of agency: rational or irrational?
Schmidt, Thomas; Heumüller, Vera C
2010-03-01
We studied how people attribute action outcomes to their own actions under conditions of uncertainty. Participants chose between left and right keypresses to produce an action effect (a corresponding left or right light), while a computer player made a simultaneous keypress decision. In each trial, a random generator determined which of the players controlled the action effect at varying probabilities, and participants then judged which player had produced it. Participants' effect control ranged from 20% to 80%, varied blockwise, and they could use trial-by-trial feedback to optimize the accuracy of their agency judgments. Participants tended to attribute action effects to themselves (agency bias), probably reflecting a rational guessing strategy of always naming the more likely player. However, participants systematically neglected information favoring the computer player as the agent, even under conditions where this bias could only harm judgment accuracy. We conclude that agency biases have both rational and irrational components.
Rational orbits around charged black holes
Misra, Vedant; Levin, Janna
2010-10-15
We show that all eccentric timelike orbits in Reissner-Nordstroem spacetime can be classified using a taxonomy that draws upon an isomorphism between periodic orbits and the set of rational numbers. By virtue of the fact that the rationals are dense, the taxonomy can be used to approximate aperiodic orbits with periodic orbits. This may help reduce computational overhead for calculations in gravitational wave astronomy. Our dynamical systems approach enables us to study orbits for both charged and uncharged particles in spite of the fact that charged particle orbits around a charged black hole do not admit a simple one-dimensional effective potential description. Finally, we show that comparing periodic orbits in the Reissner-Nordstroem and Schwarzschild geometries enables us to distinguish charged and uncharged spacetimes by looking only at the orbital dynamics.
Slipping and Rolling on an Inclined Plane
ERIC Educational Resources Information Center
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…
Solar Impulse's Solar-Powered Plane
Moniz, Ernest; Piccard, Bertrand; Reicher, Dan
2016-07-12
Solar Impulse lands in Washington, DC at Washington Dulles International Airport as part of its journey across the United States. Secretary Ernest Moniz speaks about how advancements like those at the Department of Energy are leading the way for innovations like the solar-powered plane. Footage of the solar-powered plane courtesy of Solar Impulse.
CUTTING PLANE METHODS WITHOUT NESTED CONSTRAINT SETS
General conditions are given for the convergence of a class of cutting -plane algorithms without requiring that the constraint sets for the... cutting -planes include that of Kelley and a generalization of that used by Zoutendisk and Veinott. For algorithms with nested constraint sets, these
Slipping and Rolling on an Inclined Plane
ERIC Educational Resources Information Center
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…
Solar Impulse's Solar-Powered Plane
Moniz, Ernest; Piccard, Bertrand; Reicher, Dan
2013-07-08
Solar Impulse lands in Washington, DC at Washington Dulles International Airport as part of its journey across the United States. Secretary Ernest Moniz speaks about how advancements like those at the Department of Energy are leading the way for innovations like the solar-powered plane. Footage of the solar-powered plane courtesy of Solar Impulse.
Food Allergies and Australian Combat Ration Packs
2010-05-01
an adverse outcome following the consumption of a ration pack. The removal of four readily substituted items— Chocolate and Vanilla Confectionery...Bernhisel-Broadbent, Strause and Sampson 1992). More recently it has been discovered that the dark muscle of fish (also called red muscle, used for...concentration of the allergenic compound parvalbumin (Kobayashi et al. 2006). Tuna has more dark muscle than other fish. Another finding from the same study was
Dual submanifolds in rational homology spheres
NASA Astrophysics Data System (ADS)
Fang, FuQuan
2017-09-01
Let $\\Sigma$ be a simply connected rational homology sphere. A pair of disjoint closed submanifolds $M_+, M_-$ in $\\Sigma$ are called dual to each other if the complement $\\Sigma - M_+$ strongly homotopy retracts onto $M_-$ or vice-versa. In this paper we will give a complete answer of which integral triples $(n; m_+, m_-)$ can appear, where $n=dim \\Sigma -1$, $m_+={codim}M_+ -1$ and $m_-={codim}M_- -1$.
Fluid Therapy: Options and Rational Selection.
Byers, Christopher G
2017-03-01
Administration of appropriate types and volumes of parenteral fluids is of paramount importance when treating sick and debilitated patients, especially those fighting critical illness. Fluid selection and accurate calculations must be performed logically and accurately to maximize positive outcomes. Knowledge of fluid types, as well as the complex relationship of the body's fluid compartments, helps clinicians develop rational fluid therapy plans for their patients. Copyright © 2016 Elsevier Inc. All rights reserved.
Laboratory Evaluation of Australian Ration Packs.
1981-02-01
programme. A sample of each ration component was analysed for Moisture, Fat, Ash, Protein, Thiamin ( Vitamin B1 ), Ascorbic Acid ( Vitamin C) and Salt...Soxhlet Method As described in 7.045 AOAC ( 1 0 ) except 40 - 600 C boiling petroleum solvent was the extraction reagent. The dried material from the...crystallizing dish. The method gave a standard deviation of 0.198% or 1.98% RSD for 13 paired deter- minations. 3.a. Ascorbic Acid ( Vitamin C
Laboratory Evaluation of Australian Ration Packs
1988-10-01
components have not been fortified with the vitamins thiamin. riboflavin, niacin or ascorbic acid. Approved for Public Release © Commonwealth of...and Corden (1977), Table 1. The Individual Meal Combat Ration (IMCR) was alo examined for thiamin ( vitamin BI), riboflavin (B2), sodium, phosphorus...described in Official Methods of Analysis of the Association of Official Analytical Chemists ( AOAC , 1980). Fat was determined in sweetened condensed milk
Laboratory Evaluation of Australian Ration Packs
1993-08-01
Methods 13 3. RESULTS AND DISCUSSION 14 3.1 Initial Concentrations of Vitamins for Stability Studies 14 3.1.1 EFR Trial 20 3.1.2 Encapsulated Ascorbic Acid...protein, ascorbic acid ( vitamin C), thiamine ( vitamin BI), riboflavin ( vitamin B2), niacin ( vitamin B3), and salt if a specification existed. All...Thomson, 1984; James, Lichon, Tattersall, Thomson and Hancock, 1986) have noted many cases where fortified ration components do not meet the vitamin
[What did bachelard mean by "applied rationalism" ?].
Tiles, Mary
2013-01-01
Bachelard was concerned with the processes whereby scientific knowledge is acquired, including the activity of knowing subjects. He did not equate reasoning with logic but rather argued that reasoning resulted from the use of mathematics in organizing both thought and experimental practices, which is why he conceived science as applied mathematics. This had material and technical implications, for Bachelard was concerned with the element of reason inherent in technical materialism as well as the concrete reality inherent in applied rationalism.
Integrable mappings via rational elliptic surfaces
NASA Astrophysics Data System (ADS)
Tsuda, Teruhisa
2004-02-01
We present a geometric description of the QRT map (which is an integrable mapping introduced by Quispel, Roberts and Thompson) in terms of the addition formula of a rational elliptic surface. By this formulation, we classify all the cases when the QRT map is periodic; and show that its period is 2, 3, 4, 5 or 6. A generalization of the QRT map which acts birationally on a pencil of K3 surfaces, or Calabi-Yau manifolds, is also presented.
China rationalizes its renewable energy policy
Su, Jack H.; Hui, Simone S.; Tsen, Kevin H.
2010-04-15
China's over-reliance on thermal power generation, especially coal-fired power stations, is well-documented. While nuclear power continues as an option to coal, China's strides in renewable energy are unprecedented. Recent amendments to the Renewable Energy Law, first promulgated in 2006, attempt to rationalize the regulatory regime governing wind, solar, hydropower and biomass projects in China, currently fraught with inadequate interconnection and tariff shock issues. (author)
Suicide: Rationality and Responsibility for Life
Ho, Angela Onkay
2014-01-01
Objectives: Death by suicide is widely held as an undesirable outcome. Most Western countries place emphasis on patient autonomy, a concept of controversy in relation to suicide. This paper explores the tensions between patients’ rights and many societies’ overarching desire to prevent suicide, while clarifying the relations between mental disorders, mental capacity, and rational suicide. Methods: A literature search was conducted using search terms of suicide and ethics in the PubMed and LexisNexis Academic databases. Article titles and abstracts were reviewed and deemed relevant if the paper addressed topics of rational suicide, patient autonomy or rights, or responsibility for life. Further articles were found from reference lists and by suggestion from preliminary reviewers of this paper. Results: Suicidal behaviour in a person cannot be reliably predicted, yet various associations and organizations have developed standards of care for managing patients exhibiting suicidal behaviour. The responsibility for preventing suicide tends to be placed on the treating clinician. In cases where a person is capable of making treatment decisions—uninfluenced by any mental disorder—there is growing interest in the concept of rational suicide. Conclusions: There is much debate about whether suicide can ever be rational. Designating suicide as an undesirable event that should never occur raises the debate of who is responsible for one’s life and runs the risk of erroneously attributing blame for suicide. While upholding patient rights of autonomy in psychiatric care is laudable, cases of suicidality warrant a delicate consideration of clinical judgment, duty of care, and legal obligations. PMID:24881162
NEXT Performance Curve Analysis and Validation
NASA Technical Reports Server (NTRS)
Saripalli, Pratik; Cardiff, Eric; Englander, Jacob
2016-01-01
Performance curves of the NEXT thruster are highly important in determining the thruster's ability in performing towards mission-specific goals. New performance curves are proposed and examined here. The Evolutionary Mission Trajectory Generator (EMTG) is used to verify variations in mission solutions based on both available thruster curves and the new curves generated. Furthermore, variations in BOL and EOL curves are also examined. Mission design results shown here validate the use of EMTG and the new performance curves.
Diurnal Curve of the Ocular Perfusion Pressure
Moreira, TCA; Bezerra, BSP; Vianello, MP; Corradi, J; Dorairaj, SK; Prata, TS
2016-01-01
ABSTRACT Purpose: To describe the diurnal variation of the ocular perfusion pressure (OPP) in normal, suspects and glaucoma patients. Materials and methods: Seventy-nine subjects were enrolled in a prospective study. The diurnal curve of intraocular pressure (IOP) was performed and blood pressure measurements were obtained. Each participant was grouped into one of the following based upon the clinical evaluation of the optic disk, IOP and standard achromatic perimetry (SAP): 18 eyes were classified as normal (normal SAP, normal optic disk evaluation and IOP < 21 mm Hg in two different measurements), 30 eyes as glaucoma suspect (GS) (normal SAP and mean deviation (MD), C/D ration > 0.5 or asymmetry > 0.2 and/or ocular hypertension), 31 eyes as early glaucoma (MD < -6 dB, glaucomatous optic neuropathy and SAP and MDs on SAP. Standard achromatic perimetry was performed with the Octopus 3.1.1 Dynamic 24-2 program. Intraocular pressure and blood pressure measurements were taken at 6 am, 9 am, 12, 3 and 6 pm. The patients stayed in the seated position for 5 minutes prior to blood pressure measurements. Results: The mean IOP values in all groups did not follow any regular pattern. The peak IOP was found to be greater in suspect [18.70 ± 3.31 (mm Hg ± SD)] and glaucoma (18.77 ± 4.30 mm Hg) patients as compared to normal subjects (16.11 ± 2.27 mm Hg). In studying the diurnal variation of the OPP, we found lower values at 3 pm in normals (34.21 ± 2.07 mm Hg), at 9 am in suspects (54.35 ± 3.32 mm Hg) and at 12 pm in glaucoma patients (34.84 ± 1.44 mm Hg). Conclusion: Each group has a specific OPP variation during the day with the most homogeneous group being the suspect one. It is important to keep studying the IOP and OPP variation for increased comprehension of the pathophysiology of glaucomatous optic neuropathy. How to cite this article: Kanadani FN, Moreira TCA, Bezerra BSP, Vianello MP, Corradi J, Dorairaj SK, Prata TS. Diurnal Curve of the Ocular Perfusion
Regret and the rationality of choices
Bourgeois-Gironde, Sacha
2010-01-01
Regret helps to optimize decision behaviour. It can be defined as a rational emotion. Several recent neurobiological studies have confirmed the interface between emotion and cognition at which regret is located and documented its role in decision behaviour. These data give credibility to the incorporation of regret in decision theory that had been proposed by economists in the 1980s. However, finer distinctions are required in order to get a better grasp of how regret and behaviour influence each other. Regret can be defined as a predictive error signal but this signal does not necessarily transpose into a decision-weight influencing behaviour. Clinical studies on several types of patients show that the processing of an error signal and its influence on subsequent behaviour can be dissociated. We propose a general understanding of how regret and decision-making are connected in terms of regret being modulated by rational antecedents of choice. Regret and the modification of behaviour on its basis will depend on the criteria of rationality involved in decision-making. We indicate current and prospective lines of research in order to refine our views on how regret contributes to optimal decision-making. PMID:20026463
Rational design of nanomaterials for water treatment
NASA Astrophysics Data System (ADS)
Li, Renyuan; Zhang, Lianbin; Wang, Peng
2015-10-01
The ever-increasing human demand for safe and clean water is gradually pushing conventional water treatment technologies to their limits. It is now a popular perception that the solutions to the existing and future water challenges will hinge upon further developments in nanomaterial sciences. The concept of rational design emphasizes on `design-for-purpose' and it necessitates a scientifically clear problem definition to initiate the nanomaterial design. The field of rational design of nanomaterials for water treatment has experienced a significant growth in the past decade and is poised to make its contribution in creating advanced next-generation water treatment technologies in the years to come. Within the water treatment context, this review offers a comprehensive and in-depth overview of the latest progress in rational design, synthesis and applications of nanomaterials in adsorption, chemical oxidation and reduction reactions, membrane-based separation, oil-water separation, and synergistic multifunctional all-in-one nanomaterials/nanodevices. Special attention is paid to the chemical concepts related to nanomaterial design throughout the review.
Rational design of nanomaterials for water treatment.
Li, Renyuan; Zhang, Lianbin; Wang, Peng
2015-11-07
The ever-increasing human demand for safe and clean water is gradually pushing conventional water treatment technologies to their limits. It is now a popular perception that the solutions to the existing and future water challenges will hinge upon further developments in nanomaterial sciences. The concept of rational design emphasizes on 'design-for-purpose' and it necessitates a scientifically clear problem definition to initiate the nanomaterial design. The field of rational design of nanomaterials for water treatment has experienced a significant growth in the past decade and is poised to make its contribution in creating advanced next-generation water treatment technologies in the years to come. Within the water treatment context, this review offers a comprehensive and in-depth overview of the latest progress in rational design, synthesis and applications of nanomaterials in adsorption, chemical oxidation and reduction reactions, membrane-based separation, oil-water separation, and synergistic multifunctional all-in-one nanomaterials/nanodevices. Special attention is paid to the chemical concepts related to nanomaterial design throughout the review.
Estimating Tsunami Runup with Fault Plane Parameters
NASA Astrophysics Data System (ADS)
Sepulveda, I.; Liu, P. L. F.
2016-12-01
The forecasting of tsunami runup has often been done by solving numerical models. The execution times, however, make them unsuitable for the purpose of warning. We offer an alternative method that provides analytical relationship between the runup height, the fault plane parameters and the characteristic of coastal bathymetry. The method uses the model of Okada (1985) to estimate the coseismic deformation and the corresponding sea surface displacement (η(x,0)). Once the tsunami waves are generated, Carrier & Greenspan (1958) solution (C&G) is adopted to yield analytical expressions for the shoreline elevation and velocity. Two types of problems are investigated. In the first, the bathymetry is modeled as a constant slope that is connected to a constant depth region, where a seismic event occurs. This is a boundary value problem (BVP). In the second, the bathymetry is further simplified as a constant slope, on which a seismic event occurs. This is an initial value problem (IVP). Both problems are depicted in Figure 1. We derive runup solutions in terms of the fault parameters. The earthquake is associated with vertical coseismic seafloor displacements by using Okada's elastic model. In addition to the simplifications considered in Okada's model, we further assume (1) a strike parallel to the shoreline, (2) a very long rupture area and (3) a fast earthquake so surface elevation mimics the seafloor displacements. Then the tsunami origin is modeled in terms of the fault depth (d), fault width (W), fault slip (s) and dip angle (δ). We describe the solution for the BVP. Madsen & Schaeffer (2010) utilized C&G to derive solutions for the shoreline elevation of sinusoidal waves imposed in the offshore boundary. A linear superposition of this solution represents any arbitrary incident wave. Furthermore, we can prescribe the boundary condition at the toe of sloping beach by adopting the linear shallow wave equations in the constant depth area. By means of a dimensional
Li, J; Chinachoti, P; Wang, D; Hallberg, L M; Sun, X S
2008-11-01
Beef roast with vegetables is an example of a meal, ready-to-eat (MRE) ration entrée. It is a mixture of meat, potato, mushroom, and carrot with a gravy sauce. The thermal properties of each component were characterized in terms of freezing point, latent heat, freezable and unfreezable water contents, and enthalpy during freezing using differential scanning calorimetry. Freezing and thawing curves and the effect of freezing and thawing cycles on thermal properties were also evaluated. The freezing points of beef, potato, mushroom, and sauce were all in the range of -5.1 to -5.6 degrees C, but moisture content, water activity, latent heat, freezable and unfreezable water contents, and enthalpy varied among these components. Freezing temperature greatly affected the unfrozen water fraction. The unfreezable water content (unfrozen water fraction at -50 degrees C) of ration components was in the range of 8.2% to 9.7%. The freezing and thawing curves of vegetables with sauce differed from those of beef but took similar time to freeze or thaw. Freezing and thawing cycles did not greatly affect the thermal properties of each component. Freezing point and latent heat were reduced by decreasing moisture content and water activity of each component. Water activity was proportionally linear to freezing point at a(w) > 0.88, and moisture content was proportionally linear to freezable water content in all ration components. Water was not available for freezing when moisture content was reduced to 28.8% or less. This study indicates that moisture content and water activity are critical factors affecting thermal behavior of ration components during freezing.
Refraction at a curved dielectric interface - Geometrical optics solution
NASA Technical Reports Server (NTRS)
Lee, S.-W.; Sheshadri, M. S.; Mittra, R.; Jamnejad, V.
1982-01-01
The transmission of a spherical or plane wave through an arbitrarily curved dielectric interface is solved by the geometrical optics theory. The transmitted field is proportional to the product of the conventional Fresnel's transmission coefficient and a divergence factor (DF), which describes the cross-sectional variation (convergence or divergence) of a ray pencil as the latter propagates in the transmitted region. The factor DF depends on the incident wavefront, the curvatures of the interface, and the relative indices of the two media. Explicit matrix formulas for calculating DF are given, and its physical significance is illustrated via examples.
Refraction at a curved dielectric interface - Geometrical optics solution
NASA Technical Reports Server (NTRS)
Lee, S.-W.; Sheshadri, M. S.; Mittra, R.; Jamnejad, V.
1982-01-01
The transmission of a spherical or plane wave through an arbitrarily curved dielectric interface is solved by the geometrical optics theory. The transmitted field is proportional to the product of the conventional Fresnel's transmission coefficient and a divergence factor (DF), which describes the cross-sectional variation (convergence or divergence) of a ray pencil as the latter propagates in the transmitted region. The factor DF depends on the incident wavefront, the curvatures of the interface, and the relative indices of the two media. Explicit matrix formulas for calculating DF are given, and its physical significance is illustrated via examples.
Solar concentration by curved-base Fresnel lenses
NASA Technical Reports Server (NTRS)
Cosby, R. M.
1977-01-01
The solar concentration performance of idealized curved base line focusing Fresnel lenses is analyzed. A simple optical model was introduced to study the effects of base curvature and lens f-number. Thin lens ray tracing and the laws of reflection and refraction are used to develop expression for lens transmittance and image plane intensity profiles. The intensity distribution over the solar spectrum, lens dispersion effects, and absorption by the lens material are included in the analysis. Model capabilities include assessment of lens performance in the presence of small transverse tracking errors and the sensitivity of solar image characteristics to focusing.
Should informed consent be based on rational beliefs?
Savulescu, J; Momeyer, R W
1997-01-01
Our aim is to expand the regulative ideal governing consent. We argue that consent should not only be informed but also based on rational beliefs. We argue that holding true beliefs promotes autonomy. Information is important insofar as it helps a person to hold the relevant true beliefs. But in order to hold the relevant true beliefs, competent people must also think rationally. Insofar as information is important, rational deliberation is important. Just as physicians should aim to provide relevant information regarding the medical procedures prior to patients consenting to have those procedures, they should also assist patients to think more rationally. We distinguish between rational choice/action and rational belief. While autonomous choice need not necessarily be rational, it should be based on rational belief. The implication for the doctrine of informed consent and the practice of medicine is that, if physicians are to respect patient autonomy and help patients to choose and act more rationally, not only must they provide information, but they should care more about the theoretical rationality of their patients. They should not abandon their patients to irrationality. They should help their patients to deliberate more effectively and to care more about thinking rationally. We illustrate these arguments in the context of Jehovah's Witnesses refusing life-saving blood transfusions. Insofar as Jehovah's Witnesses should be informed of the consequences of their actions, they should also deliberate rationally about these consequences. PMID:9358347
Rational Emotive Behavior Therapy Successes and Failures: Eight Personal Perspectives.
ERIC Educational Resources Information Center
Weinrach, Stephen G.; Ellis, Albert; MacLaren, Catharine; DiGiuseppe, Raymond; Vernon, Ann; Wolfe, Janet; Malkinson, Ruth; Backx, Wouter
2001-01-01
Eight experts in Rational Emotive Behavior Therapy (REBT) provide personal examples of their own successes and failures in applying REBT to themselves. The experts actively talked to themselves both rationally and irrationally. Rational self-talk was more prevalent in the examples of how REBT was successfully used by the experts. (GCP)
Cognitive Rationality and Its Logic-Mathematical Language
ERIC Educational Resources Information Center
Masalova, Svetlana
2012-01-01
The article deals with the cognitive (flexible) rationality, combining rational and irrational moments of the scientific search of the cognizing subject. Linguo-cognitive model of the concept as the flexible regulative rationality reveals the activity of the cognitive processes and the mentality of the epistemological-ontic subject, its leading…
Rationalization and the Role of the School Counselor.
ERIC Educational Resources Information Center
Clark, Arthur J.
1995-01-01
Examines rationalization in counselors' interactions with students, parents, and teachers--provides examples of each kind of interaction. Describes the dynamics of rationalization in the schools and outlines interventions that may be used with students, parents, and teachers. Also explores counselors' use of rationalization and gives examples of…
Rational Analyses of Information Foraging on the Web
ERIC Educational Resources Information Center
Pirolli, Peter
2005-01-01
This article describes rational analyses and cognitive models of Web users developed within information foraging theory. This is done by following the rational analysis methodology of (a) characterizing the problems posed by the environment, (b) developing rational analyses of behavioral solutions to those problems, and (c) developing cognitive…
Rational Analyses of Information Foraging on the Web
ERIC Educational Resources Information Center
Pirolli, Peter
2005-01-01
This article describes rational analyses and cognitive models of Web users developed within information foraging theory. This is done by following the rational analysis methodology of (a) characterizing the problems posed by the environment, (b) developing rational analyses of behavioral solutions to those problems, and (c) developing cognitive…
Study the Z-Plane Strip Capacitance
Parikh, H.; Swain, S.; /SLAC
2005-12-15
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 ({phi} coordinate) and a single ''Z-plane'' which provides the Z coordinate of the hit. The large area Z-planes (up to 12m{sup 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.
NASA Astrophysics Data System (ADS)
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.
Principal Curves on Riemannian Manifolds.
Hauberg, Soren
2016-09-01
Euclidean statistics are often generalized to Riemannian manifolds by replacing straight-line interpolations with geodesic ones. While these Riemannian models are familiar-looking, they are restricted by the inflexibility of geodesics, and they rely on constructions which are optimal only in Euclidean domains. We consider extensions of Principal Component Analysis (PCA) to Riemannian manifolds. Classic Riemannian approaches seek a geodesic curve passing through the mean that optimizes a criteria of interest. The requirements that the solution both is geodesic and must pass through the mean tend to imply that the methods only work well when the manifold is mostly flat within the support of the generating distribution. We argue that instead of generalizing linear Euclidean models, it is more fruitful to generalize non-linear Euclidean models. Specifically, we extend the classic Principal Curves from Hastie & Stuetzle to data residing on a complete Riemannian manifold. We show that for elliptical distributions in the tangent of spaces of constant curvature, the standard principal geodesic is a principal curve. The proposed model is simple to compute and avoids many of the pitfalls of traditional geodesic approaches. We empirically demonstrate the effectiveness of the Riemannian principal curves on several manifolds and datasets.
Archaeomagnetic SV curve for Belgium
NASA Astrophysics Data System (ADS)
Ech-chakrouni, Souad; Hus, Jozef
2017-04-01
Archaeomagnetic secular variation curves have been established for different countries in Europe, especially when different archeological sites are more or less uniformly distributed in time are available. The disadvantage in that case is that data had to be relocated to a single reference site. The proximity of the reference locality Paris to Belgium makes that we used the French archaeomagnetic SV curve for the last three millennia up to the present for archaeomagnetic dating undated baked structures. In total, 85 baked structures have been examined, unearthed in 24 archaeological sites of the territory of Belgium. The ChRM of each sample was obtained by principal component analysis for at least three demagnetisation steps (Kirschvink 1980). Except for some outliers, the ChRM directions are very coherent with a high confidence factor (α95< 5°) and high concentration factor. The average field directions recorded in the fired materials in most sites satisfy the international criteria used in archaeomagnetism. At present, only six baked structures were dated radiometrically and may be considered as reference data for a limited area about 30500 km2 in Western Europe. The ultimate aim is to construct an archaeomagnetic SV curve for Belgium with Uccle as reference locality, where the first measurement of the geomagnetic field was done in 1895. This curve would include all the available reference data in a radius of about 500 km around Uccle. Keywords: secular variation, archaeomagnetic dating, Belgium.
Interpolation and Polynomial Curve Fitting
ERIC Educational Resources Information Center
Yang, Yajun; Gordon, Sheldon P.
2014-01-01
Two points determine a line. Three noncollinear points determine a quadratic function. Four points that do not lie on a lower-degree polynomial curve determine a cubic function. In general, n + 1 points uniquely determine a polynomial of degree n, presuming that they do not fall onto a polynomial of lower degree. The process of finding such a…
Variability among polysulphone calibration curves
NASA Astrophysics Data System (ADS)
Casale, G. R.; Borra, M.; Colosimo, A.; Colucci, M.; Militello, A.; Siani, A. M.; Sisto, R.
2006-09-01
Within an epidemiological study regarding the correlation between skin pathologies and personal ultraviolet (UV) exposure due to solar radiation, 14 field campaigns using polysulphone (PS) dosemeters were carried out at three different Italian sites (urban, semi-rural and rural) in every season of the year. A polysulphone calibration curve for each field experiment was obtained by measuring the ambient UV dose under almost clear sky conditions and the corresponding change in the PS film absorbance, prior and post exposure. Ambient UV doses were measured by well-calibrated broad-band radiometers and by electronic dosemeters. The dose-response relation was represented by the typical best fit to a third-degree polynomial and it was parameterized by a coefficient multiplying a cubic polynomial function. It was observed that the fit curves differed from each other in the coefficient only. It was assessed that the multiplying coefficient was affected by the solar UV spectrum at the Earth's surface whilst the polynomial factor depended on the photoinduced reaction of the polysulphone film. The mismatch between the polysulphone spectral curve and the CIE erythemal action spectrum was responsible for the variability among polysulphone calibration curves. The variability of the coefficient was related to the total ozone amount and the solar zenith angle. A mathematical explanation of such a parameterization was also discussed.
Supply Curves of Conserved Energy
Meier, Alan Kevin
1982-05-01
Supply curves of conserved energy provide an accounting framework that expresses the potential for energy conservation. The economic worthiness of a conservation measure is expressed in terms of the cost of conserved energy, and a measure is considered economical when the cost of conserved energy is less than the price of the energy it replaces. A supply curve of conserved energy is independent of energy prices; however, the economical reserves of conserved energy will depend on energy prices. Double-counting of energy savings and error propagation are common problems when estimating conservation potentials, but supply curves minimize these difficulties and make their consequences predictable. The sensitivity of the cost of conserved energy is examined, as are variations in the optimal investment strategy in response to changes in inputs. Guidelines are presented for predicting the consequences of such changes. The conservation supply curve concept can be applied to peak power, water, pollution, and other markets where consumers demand a service rather than a particular good.
Interpolation and Polynomial Curve Fitting
ERIC Educational Resources Information Center
Yang, Yajun; Gordon, Sheldon P.
2014-01-01
Two points determine a line. Three noncollinear points determine a quadratic function. Four points that do not lie on a lower-degree polynomial curve determine a cubic function. In general, n + 1 points uniquely determine a polynomial of degree n, presuming that they do not fall onto a polynomial of lower degree. The process of finding such a…
Breakpoint chlorination curves of greywater.
March, J G; Gual, M
2007-08-01
A study on chlorination of raw greywater with hypochlorite is reported in this paper. Samples were chlorinated in a variety of conditions, and residual chlorine (Cl2) was measured spectrophotometrically. For each sample, the chlorination curve (chlorine residuals versus chlorine dose) was obtained. Curves showed the typical hump-and-dip profile attributable to the formation and destruction of chloramines. It was observed that, after reactions with strong reductants and chloramines-forming compounds, the remaining organic matter exerted a certain demand of chlorine. The evolution of chlorination curves with addition of ammonia and dodecylbencene sulfonate sodium salt and with dilution of the greywater sample were studied. In addition, chlorination curves at several contact times have been obtained, resulting in slower chlorine decay in the hump zone than in the dip zone. In addition, the decay of coliforms in chlorinated samples was also investigated. It was found that, for a chlorination dosage corresponding to the maximum of the hump zone (average 8.9 mg Cl2/ L), samples were negative in coliforms after 10 to 30 minutes of contact time. After-growth was not observed within 3 days after chlorination. Implications in chlorination treatments of raw greywater can be derived from these results.
Modeling and Visualization Process of the Curve of Pen Point by GeoGebra
ERIC Educational Resources Information Center
Aktümen, Muharem; Horzum, Tugba; Ceylan, Tuba
2013-01-01
This study describes the mathematical construction of a real-life model by means of parametric equations, as well as the two- and three-dimensional visualization of the model using the software GeoGebra. The model was initially considered as "determining the parametric equation of the curve formed on a plane by the point of a pen, positioned…
A half plane and a strip with an arbitrarily located crack
NASA Technical Reports Server (NTRS)
Erdogan, F.; Arin, K.
1973-01-01
A technique is presented for dealing with the problem of an elastic domain containing an arbitrarily oriented internal crack. The problem is formulated as a system of integral equations for a fictitious layer of body forces imbedded in the plane along a closed smooth curve encircling the original domain. The problems of a half plane with a crack in the neighborhood of its free boundary and of an infinite strip containing a symmetrically located internal crack with an arbitrary orientation are considered as examples. In each case the stress intensity factors are computed and are given as functions of the crack angle.
Plane-parallel waves as duals of the flat background II: T-duality with spectators
NASA Astrophysics Data System (ADS)
Petrásek, Filip; Hlavatý, Ladislav; Petr, Ivo
2017-08-01
We give the classification of T-duals of the flat background in four dimensions with respect to one-, two-, and three-dimensional subgroups of the Poincaré group using non-Abelian T-duality with spectators. As duals we find backgrounds for sigma models in the form of plane-parallel waves or diagonalizable curved metrics often with torsion. Among others, we find exactly solvable time-dependent isotropic pp-wave, singular pp-waves, or generalized plane wave (K-model).
Guo, Mingxing; Gu, Hao; Song, Yuelin; Peng, Long; Liu, Haiyu; Zhang, Li; Lin, Zhaozhou; Wang, Yun; Gao, Xiaoyan; Qiao, Yanjiang
2014-07-01
Fever is a prominent feature of diseases and is an ongoing process that is always accompanied by metabolic changes in the body system. Despite the success of temperature regulation theory, the underlying biological process remains unclear. To truly understand the nature of the febrile response, it is crucial to confirm the biomarkers during the entire biological process. In the current study, a 73-h metabolic footprint analysis of the urine from yeast-induced pyrexia rats was performed using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Potential biomarkers were selected using orthogonal partial least squares-discriminate analysis (OPLS-DA), the rational biomarkers were verified by Pearson correlation analysis, and the predictive power was evaluated using receiver operator characteristic (ROC) curves. A metabolic network constructed using traditional Chinese medicine (TCM) grammar systems was used to validate the rationality of the verified biomarkers. Finally, five biomarkers, including indoleacrylic acid, 3-methyluridine, tryptophan, nicotinuric acid and PI (37:3), were confirmed as rational biomarkers because their correlation coefficients were all greater than 0.87 and because all of the correlation coefficients between any pair of these biomarkers were higher than 0.75. The areas under the ROC curves were all greater than 0.84, and their combined predictive power was considered reliable because the greatest area under the ROC curve was 0.968. A metabolic network also demonstrated the rationality of these five biomarkers. Therefore, these five metabolites can be adopted as rational biomarkers to reflect the process of the febrile response in inflammation-induced pyrexia. Copyright © 2014 Elsevier B.V. All rights reserved.
Nayar, Sanjna; Dinakarsamy, V.; Santhosh, S.
2015-01-01
Occlusal plane is an essential consideration when multiple long-span posterior restorations are designed. When restorations are added to an existing tooth arrangement characterized by rotated, tipped, or extruded teeth, excursive interferences may be incorporated, resulting in detrimental squeal. The curve of Spee, which exists in the ideal natural dentition, allows harmony to exist between the anterior tooth and condylar guidance. This curve exists in the sagittal plane and is the best viewed from a lateral aspect. It permits total posterior disclusion on mandibular protrusion, given proper anterior tooth guidance. It is unclear that whether the curve of Spee is a description of the occlusal surface of each arch separately or in maximal intercuspation. The purpose of this study was to examine the differences in the depth of curve of Spee between the class I, class II, class III and to investigate the relationship of depth of curve of Spee with over jet, over-bite. PMID:26015764
Transverse plane motion at the ankle joint.
Nester, Christopher J; Findlow, Andrew F; Bowker, Peter; Bowden, Peter D
2003-02-01
The ankle is often considered to have little or no capacity to move in the transverse plane. This is clear in the persistent concept that it is the role of the subtalar joint to accommodate the transverse plane motion of the leg while the foot remains in a fixed transverse plane position on the floor. We present data from noninvasive in vivo study of the ankle subtalar complex during standing internal and external rotation of the leg and study of the ankle subtalar complex during walking. These data reinforce the results of cadaver study and invasive in vivo study of the ankle/subtalar complex. We suggest that the ankle is capable of considerable movement in the transverse plane (generally greater than 15 degrees) and that its role in the mechanism that allows the foot to remain in a fixed transverse plane position on the floor while the leg rotates in the transverse plane, is not simply the transfer of the transverse plane moment to the subtalar joint, but is accommodation of some of the necessary movement.
Rational-spline approximation with automatic tension adjustment
NASA Technical Reports Server (NTRS)
Schiess, J. R.; Kerr, P. A.
1984-01-01
An algorithm for weighted least-squares approximation with rational splines is presented. A rational spline is a cubic function containing a distinct tension parameter for each interval defined by two consecutive knots. For zero tension, the rational spline is identical to a cubic spline; for very large tension, the rational spline is a linear function. The approximation algorithm incorporates an algorithm which automatically adjusts the tension on each interval to fulfill a user-specified criterion. Finally, an example is presented comparing results of the rational spline with those of the cubic spline.
What Information Theory Says about Bounded Rational Best Response
NASA Technical Reports Server (NTRS)
Wolpert, David H.
2005-01-01
Probability Collectives (PC) provides the information-theoretic extension of conventional full-rationality game theory to bounded rational games. Here an explicit solution to the equations giving the bounded rationality equilibrium of a game is presented. Then PC is used to investigate games in which the players use bounded rational best-response strategies. Next it is shown that in the continuum-time limit, bounded rational best response games result in a variant of the replicator dynamics of evolutionary game theory. It is then shown that for team (shared-payoff) games, this variant of replicator dynamics is identical to Newton-Raphson iterative optimization of the shared utility function.