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Sample records for rational plane curves

  1. Craniofacial Reconstruction Using Rational Cubic Ball Curves

    PubMed Central

    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

  2. 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…

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Projecting diffusion along the normal bundle of a plane curve

    SciTech Connect

    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.

  8. 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.

  9. 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

  10. A curve shortening flow rule for closed embedded plane curves with a prescribed rate of change in enclosed area

    PubMed Central

    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

  11. A curve shortening flow rule for closed embedded plane curves with a prescribed rate of change in enclosed area.

    PubMed

    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.

  12. Performance characteristics of a curved-channel microchannel plate with a curved input face and a plane output face

    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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. IMAGE-PLANE ANALYSIS OF n-POINT-MASS LENS CRITICAL CURVES AND CAUSTICS

    SciTech Connect

    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.

  18. 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.

  19. 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

  20. The Definition and Computation of a Metric on Plane Curves. The Meaning of a Face on a Geometric Model

    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.

  1. 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.

  2. 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.

  3. Dome Shape Optimization of Composite Pressure Vessels Based on Rational B-Spline Curve and Genetic Algorithm

    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.

  4. Development of cubic Bezier curve and curve-plane intersection method for parametric submarine hull form design to optimize hull resistance using CFD

    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.

  5. The Influence of the Load Model and other Parameters on the Dynamic Behavior of Curved-in-Plane Bridges

    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.

  6. On the cost of approximating and recognizing a noise perturbed straight line or a quadratic curve segment in the plane. [central processing units

    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.

  7. On the Dirichlet problem for the Helmholtz equation on the plane with boundary conditions on an almost closed curve

    SciTech Connect

    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.

  8. 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.

  9. Surface Activation of Plane and Curved Automotive Polymer Surfaces by Using a Fittable Multi-Pin DBD Plasma Source

    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.

  10. 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.

  11. Acoustic plane waves normally incident on a clamped panel in a rectangular duct. [to explain noise reduction curves for reducing interior noise in aircraft

    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.

  12. An investigation of the diffraction of an acoustic plane wave by a curved surface of finite impedance. Ph.D. Thesis Final Technical Report, 1 Feb. 1985 - 1 Sep. 1989

    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.

  13. Confucian Rationalism

    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,…

  14. Rational Teaching.

    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)

  15. Microorganism billiards in closed plane curves.

    PubMed

    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.

  16. Rational Belief.

    DTIC Science & Technology

    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

  17. Rational-Spline Subroutines

    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.

  18. 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…

  19. 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.

  20. Graphing Polar Curves

    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…

  1. Monotone data visualization using rational trigonometric spline interpolation.

    PubMed

    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.

  2. RATIONAL SPLINE SUBROUTINES

    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.

  3. Precise measurement of planeness.

    PubMed

    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.

  4. Automated reasoning about cubic curves.

    SciTech Connect

    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.

  5. 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.

  6. Causal inheritence in plane wave quotients

    SciTech Connect

    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.

  7. Quantization on Curves

    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.

  8. Bradford Curves.

    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)

  9. Standby Gasoline Rationing Plan

    SciTech Connect

    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)

  10. Alternative Disaster Feeding Ration

    DTIC Science & Technology

    2012-06-08

    or relations with each ration type: MREs are not vegetarian ; HDRs are religiously sensitive; and high calorie bars appear minimalistic implying lack...each ration type: MREs are not vegetarian ; HDRs are religiously sensitive; and high calorie bars appear minimalistic implying lack of compassion

  11. 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,…

  12. 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

  13. [Concepts of rational taxonomy].

    PubMed

    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

  14. Fuzzy capital rationing model

    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.

  15. Rationality and social behavior.

    PubMed

    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

  16. 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.

  17. Rational enzyme redesign

    SciTech Connect

    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.

  18. 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.

  19. Occlusal plane determination using custom made broadrick occlusal plane analyser: a case control study.

    PubMed

    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.

  20. Fourier plane imaging microscopy

    SciTech Connect

    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.

  1. 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.

  2. Rational drug design.

    PubMed

    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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Bound Rationality and Organizational Learning.

    DTIC Science & Technology

    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 𔄃 ABSTRACT (Continue on reverse if necessary

  8. Who Should Ration?

    PubMed

    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."

  9. Critical care rationing: international comparisons.

    PubMed

    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.

  10. 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…

  11. 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…

  12. 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)

  13. Evaluation of the Rational Environment

    DTIC Science & Technology

    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

  14. Axial Plane Optical Microscopy

    PubMed Central

    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

  15. SNAP focal plane

    SciTech Connect

    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.

  16. Single-shot curved slice imaging.

    PubMed

    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.

  17. Plane Jane(s).

    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)

  18. 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.

  19. Dependent rational providers.

    PubMed

    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.

  20. 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.

  1. Parameter Plane Design Method

    DTIC Science & Technology

    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

  2. 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.

  3. McLuhan and Rationality.

    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)

  4. 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.

  5. Lower extremity kinematics of athletics curve sprinting.

    PubMed

    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.

  6. "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…

  7. 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.

  8. 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.

  9. The Aerodynamic Plane Table

    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.

  10. Fourier plane image amplifier

    DOEpatents

    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.

  11. Fourier plane image amplifier

    DOEpatents

    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.

  12. 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.

  13. 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.

  14. Out-of-plane properties

    SciTech Connect

    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.

  15. Out-of-plane properties

    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

  16. Traction curves for the decohesion of covalent crystals

    NASA Astrophysics Data System (ADS)

    Enrique, Raúl A.; Van der Ven, Anton

    2017-01-01

    We study, by first principles, the energy versus separation curves for the cleavage of a family of covalent crystals with the diamond and zincblende structure. We find that there is universality in the curves for different materials which is chemistry independent but specific to the geometry of the particular cleavage plane. Since these curves do not strictly follow the universal binding energy relationship (UBER), we present a derivation of an extension to this relationship that includes non-linear force terms. This extended form of UBER allows for a flexible and practical mathematical description of decohesion curves that can be applied to the quantification of cohesive zone models.

  17. 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)

  18. The Skipping Rope Curve

    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.)

  19. 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…

  20. Flow-duration curves

    USGS Publications Warehouse

    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.

  1. Simulating Supernova Light Curves

    SciTech Connect

    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.

  2. 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.

  3. NASA Connect: 'Plane Weather'

    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 they form. 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.

  4. NASA Connect: 'Plane Weather'

    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.

  5. CURVES: curve evolution for vessel segmentation.

    PubMed

    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.

  6. 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.

  7. 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)

  8. 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.

  9. Mechanics of Curved Folds

    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.

  10. 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.

  11. 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.

  12. 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.

  13. Air-Activated Ration Heaters

    DTIC Science & Technology

    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

  14. Psychology and the Rationality of Emotion*

    PubMed Central

    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

  15. 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…

  16. 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.

  17. Epitaxial growth, electrical and optical properties of a-plane InN on r-plane sapphire

    SciTech Connect

    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.

  18. The sales learning curve.

    PubMed

    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.

  19. Dynamics of curved interfaces

    SciTech Connect

    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.

  20. 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.

  1. Curve of Spee - from orthodontic perspective

    PubMed Central

    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

  2. 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.

  3. Curved butterfly bileaflet prosthetic cardiac valve

    DOEpatents

    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.

  4. 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…

  5. 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)

  6. 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)

  7. Curve Fit Challenge

    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.

  8. The Bacterial Growth Curve.

    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)

  9. Sagittal focusing of synchrotron x radiation with curved crystals

    SciTech Connect

    Sparks, C.J. Jr.; Ice, G.E.; Wong, J.; Batterman, B.W.

    1981-01-01

    We describe the sagittal focusing of x rays with singly bent crystals that accept the meridian plane divergence from a similar but flat crystal to form a pair in a nondispersive two-crystal Bragg monochromator. Curved crystals can intercept from 5 to 20 times the sagittal divergence of curved mirrors at x-ray energies above 10 keV. Anticlastic (transverse) bending of the crystal is made negligible in the meridian plane with reinforcing ribs cut parallel to the plane of scattering. Results show that at energies of 10, 20, and 30 keV the bent crystal performs efficiently and images the source size at the Cornell High Energy Synchrotron Source.

  10. Pleats in crystals on curved surfaces.

    PubMed

    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.

  11. 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.

  12. National Aerospace Plane (NASP) program

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Artists concept of the X-30 aerospace plane flying through Earth's atmosphere on its way to low-Earth orbit. the experimental concept is part of the National Aero-Space Plane Program. The X-30 is planned to demonstrate the technology for airbreathing space launch and hypersonic cruise vehicles. Photograph and caption published in Winds of Change, 75th Anniversary NASA publication (page 117), by James Schultz.

  13. Rational Prescription for a Dermatologist

    PubMed Central

    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

  14. 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.

  15. Modeling magnetization curves in magnetic thin films with striped patterns.

    PubMed

    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.

  16. 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.

  17. Trishear for curved faults

    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.

  18. Atlas of fatigue curves

    SciTech Connect

    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.

  19. Mouse Curve Biometrics

    SciTech Connect

    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.

  20. 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.

  1. High speed curved position sensitive detector

    DOEpatents

    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.

  2. Laboratory Evaluation of Australian Ration Packs.

    DTIC Science & Technology

    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

  3. 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.

  4. Scottish psychoanalysis: a rational religion.

    PubMed

    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.

  5. 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.

  6. 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.

  7. Rotation Curves of Galaxies

    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.

  8. Curved PVDF airborne transducer.

    PubMed

    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.

  9. 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.

  10. Magnetism in curved geometries

    SciTech Connect

    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.

  11. Magnetism in curved geometries

    DOE PAGES

    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

  12. Explosive plane-wave lens

    DOEpatents

    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.

  13. Explosive plane-wave lens

    DOEpatents

    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.

  14. Explosive plane-wave lens

    DOEpatents

    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.

  15. Complementary Curves of Descent

    DTIC Science & Technology

    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

  16. Curved cap corrugated sheet

    NASA Technical Reports Server (NTRS)

    Davis, R. C.; Bales, T. T.; Royster, D. M.; Jackson, L. R. (Inventor)

    1984-01-01

    The report describes a structure for a strong, lightweight corrugated sheet. The sheet is planar or curved and includes a plurality of corrugation segments, each segment being comprised of a generally U-shaped corrugation with a part-cylindrical crown and cap strip, and straight side walls and with secondary corrugations oriented at right angles to said side walls. The cap strip is bonded to the crown and the longitudinal edge of said cap strip extends beyond edge at the intersection between said crown and said side walls. The high strength relative to weight of the structure makes it desirable for use in aircraft or spacecraft.

  17. Max Weber's Types of Rationality: Cornerstones for the Analysis of Rationalization Processes in History.

    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)

  18. 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.

  19. 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.

  20. 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…

  1. 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…

  2. 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.

  3. 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.

  4. 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…

  5. Fiber sources for complete calf starter rations.

    PubMed

    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.

  6. 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…

  7. 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…

  8. 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…

  9. 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.…

  10. Multiple CubicBezier Curves.

    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)

  11. 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…

  12. 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.

  13. 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.

  14. 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.

  15. Section curve reconstruction and mean-camber curve extraction of a point-sampled blade surface.

    PubMed

    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.

  16. Section Curve Reconstruction and Mean-Camber Curve Extraction of a Point-Sampled Blade Surface

    PubMed Central

    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

  17. A heuristic for the distribution of point counts for random curves over a finite field

    PubMed Central

    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

  18. Bimetallic PtxCoy nanoparticles with curved faces for highly efficient hydrogenation of cinnamaldehyde

    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

  19. Eight plane IPND mechanical testing.

    SciTech Connect

    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

  20. 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.

  1. SETI in the Ecliptic Plane

    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.

  2. 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.

  3. 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.

  4. Skyrmions, rational maps, and scaling identities

    SciTech Connect

    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.

  5. 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

  6. Surface path lines in plane stokes flow driven by capillarity

    SciTech Connect

    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.

  7. Rational emotive behavior therapy: disputing irrational philosophies.

    PubMed

    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.

  8. 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.

  9. Intergroup Conflict and Rational Decision Making

    PubMed Central

    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

  10. 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.

  11. Shape Preserving Interpolation by Curves

    DTIC Science & Technology

    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

  12. 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.

  13. Augmented-plane-wave forces

    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.

  14. SNAP Satellite Focal Plane Development

    SciTech Connect

    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.

  15. 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.

  16. Comparison of parameters of spinal curves in the sagittal plane measured by photogrammetry and inclinometry.

    PubMed

    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.

  17. 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…

  18. Military Applications of Curved Focal Plane Arrays Developed by the HARDI Program

    DTIC Science & Technology

    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 toolcomputer codeto study the effects of various

  19. 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.

  20. 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.

  1. Image plane sweep volume illumination.

    PubMed

    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.

  2. Learning curves in health care.

    PubMed

    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.

  3. 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.

  4. 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)

  5. Rational drug design applied to myeloperoxidase inhibition.

    PubMed

    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.

  6. Dilemmas in rationing health care services: the case for implicit rationing.

    PubMed Central

    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

  7. 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.

  8. Functional Aesthetic Occlusal Plane (FAOP)

    PubMed Central

    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

  9. 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.

  10. 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.**

  11. Snakes Out of the Plane

    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.''

  12. Broken chiral symmetry on a null plane

    SciTech Connect

    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.

  13. Changing Conspiracy Beliefs through Rationality and Ridiculing

    PubMed Central

    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

  14. Autonomy, rationality and the wish to die.

    PubMed Central

    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

  15. Changing Conspiracy Beliefs through Rationality and Ridiculing.

    PubMed

    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.

  16. Accelerating Around an Unbanked Curve

    DTIC Science & Technology

    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

  17. Curved conveyor section guide assembly

    SciTech Connect

    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.

  18. 2-tier in-plane motion correction and out-of-plane motion filtering for contrast-enhanced ultrasound

    PubMed Central

    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

  19. 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.

  20. 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.

  1. 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.

  2. Rationality: a social-epistemology perspective

    PubMed Central

    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

  3. [The role of economics in fair rationing].

    PubMed

    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.

  4. 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

  5. A cephalometric study to determine the center of anteroposterior curve of occlusion in the cranium.

    PubMed

    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.

  6. Comparison of curve shape between children with cerebral palsy, Friedreich's ataxia, and adolescent idiopathic scoliosis.

    PubMed

    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).

  7. 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).

  8. 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.

  9. 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.

  10. Sagittal plane deformity: an overview of interpretation and management.

    PubMed

    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.

  11. Sagittal plane deformity: an overview of interpretation and management

    PubMed Central

    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

  12. 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

  13. Mathematical definition of the curve of Spee in permanent healthy dentitions in man.

    PubMed

    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.

  14. 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.

  15. 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.

  16. 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.

  17. 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…

  18. 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…

  19. 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…

  20. 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)

  1. 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…

  2. 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…

  3. 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…

  4. Medicine, ethics and religion: rational or irrational?

    PubMed Central

    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

  5. 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)

  6. 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…

  7. 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)

  8. 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…

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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).

  17. Nanostructured carbon films with oriented graphitic planes

    SciTech Connect

    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.

  18. Rational Choice and Developmental Influences on Recidivism Among Adolescent Felony Offenders

    PubMed Central

    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

  19. 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.

  20. 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.

  1. 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).).

  2. 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.

  3. 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.

  4. Curve Fit Technique for a Smooth Curve Using Gaussian Sections.

    DTIC Science & Technology

    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

  5. Harmonic Measure of Critical Curves

    SciTech Connect

    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.

  6. 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.

  7. 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.

  8. 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.

  9. 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…

  10. Solar Impulse's Solar-Powered Plane

    ScienceCinema

    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.

  11. Solar Impulse's Solar-Powered Plane

    SciTech Connect

    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.

  12. 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.

  13. 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.

  14. Competency to Proceed to Trial Evaluations and Rational Understanding.

    PubMed

    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.

  15. 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)

  16. Diurnal Curve of the Ocular Perfusion Pressure

    PubMed Central

    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

  17. The origin of bounded rationality and intelligence.

    PubMed

    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.

  18. Rational orbits around charged black holes

    SciTech Connect

    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.

  19. Rationally Irrational: The Case of Sexual Burglary.

    PubMed

    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.

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

    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.

  1. Study the Z-Plane Strip Capacitance

    SciTech Connect

    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.

  2. Innovative Ration Preservation via Supercritical Carbon Dioxide

    DTIC Science & Technology

    2012-07-01

    regarded as safe (GRAS) treatment and a novel alternative to traditional thermal processing, which can cause product quality degradation. The CO2 is...reactions continuously occur in food, causing constant changes. Food enzymes and microbes are associated with loss of product quality such as browning...components can also cause product quality degradation. There is a critical need in combat rations for a generally regarded as safe (GRAS), non

  3. The Long Life Ration Packet (LLRP)

    DTIC Science & Technology

    1991-02-18

    50 202 Coffee, cream and sugar 13 52 Total 353 1540 MENU 2 Beef Stew 140 692 Granola bar 43 209 Chocolate covered cookie 43 226 Caramels 35 149 Cocoa ...jelly chocolate icing Fruit cocktail Coffee Coffee Sugar cookies Cocoa Tea Coffee Orange beverage Tea Fruit punch beverage 10 Gross weight/ration 3.639...Chicken Stew Pork with Escalloped Corn Flake Bar, Orange Enriched Sweet Chocolate Potatoes Flavored Bar with Almonds Fruitcake Bar Cocoa Beverage

  4. 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.

  5. China rationalizes its renewable energy policy

    SciTech Connect

    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)

  6. 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…

  7. Thermal properties of ration components as affected by moisture content and water activity during freezing.

    PubMed

    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.

  8. Supply Curves of Conserved Energy

    SciTech Connect

    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.

  9. 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…

  10. 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.

  11. Breakpoint chlorination curves of greywater.

    PubMed

    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.

  12. 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.

  13. Regret and the rationality of choices

    PubMed Central

    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

  14. Evaluation depth of the curve of Spee in class I, class II, and class III malocclusion: A cross sectional study

    PubMed Central

    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

  15. 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…

  16. 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…

  17. Should informed consent be based on rational beliefs?

    PubMed Central

    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

  18. 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…

  19. Capacitance of edge plane of pyrolytic graphite in acetonitrile solutions

    SciTech Connect

    Minick, S.K.; Ishida, Takanobu.

    1991-05-01

    The capacitance of the edge plane of pyrolytic graphite electrodes, in acetonitrile solutions, is measured by recording the current response to an applied triangular voltage sweep; TVS, and then fitting the current response with an appropriate function, (via a set of adjustable parameters). The pretreatment of the electrodes, the supporting electrolyte concentration used, and the frequency of the input TVS, were all found to affect the measured capacitance. In these experiments, a background current was also seen and the shape of the current output for the TVS; the charging/discharging curve, is shown to correlate with the magnitude of this background current. In addition, the size of the background current was found to have some dependence on the type of electrode pretreatment procedure used. 60 refs., 49 figs., 3 tabs.

  20. Lower incisor inclination regarding different reference planes.

    PubMed

    Zataráin, Brenda; Avila, Josué; Moyaho, Angeles; Carrasco, Rosendo; Velasco, Carmen

    2016-09-01

    The purpose of this study was to assess the degree of lower incisor inclination with respect to different reference planes. It was an observational, analytical, longitudinal, prospective study conducted on 100 lateral cephalograms which were corrected according to the photograph in natural head position in order to draw the true vertical plane (TVP). The incisor mandibular plane angle (IMPA) was compensated to eliminate the variation of the mandibular plane growth type with the formula "FMApx.- 25 (FMA) + IMPApx. = compensated IMPA (IMPACOM)". As the data followed normal distribution determined by the KolmogorovSmirnov test, parametric tests were used for the statistical analysis, Ttest, ANOVA and Pearson coefficient correlation test. Statistical analysis was performed using a statistical significance of p <0.05. There is correlation between TVP and NB line (NB) (0.8614), Frankfort mandibular incisor angle (FMIA) (0.8894), IMPA (0.6351), Apo line (Apo) (0.609), IMPACOM (0.8895) and McHorris angle (MH) (0.7769). ANOVA showed statistically significant differences between the means for the 7 variables with 95% confidence level, P=0.0001. The multiple range test showed no significant difference among means: APoNB (0.88), IMPAMH (0.36), IMPANB (0.65), FMIAIMPACOM (0.01), FMIATVP (0.18), TVPIMPACOM (0.17). There was correlation among all reference planes. There were statistically significant differences among the means of the planes measured, except for IMPACOM, FMIA and TVP. The IMPA differed significantly from the IMPACOM. The compensated IMPA and the FMIA did not differ significantly from the TVP. The true horizontal plane was mismatched with Frankfort plane in 84% of the sample with a range of 19°. The true vertical plane is adequate for measuring lower incisor inclination.

  1. Mosaic focal plane for star sensors

    NASA Astrophysics Data System (ADS)

    Chang, N. C.

    1981-02-01

    The basic principles of star sensors are reviewed with reference to the advantages of replacing photodiodes, image dissectors, and vidicons with mosaic charge transfer device (CTD) focal planes. The desirable characteristics of CTD focal planes include: high uniformity, high transfer effect, low dark current, low hot and cold spots, low dead space, low angular misalignment, high coplanarity, and high thermal stability. An implementation of a mosaic CTD array star sensor which achieves high angular position accuracy and frequency attitude update is presented. Two focal plane packaging concepts, the planar and vertical board packagings, are examined.

  2. 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.

  3. 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.

  4. The linear stability of plane stagnation-point flow against general disturbances

    NASA Astrophysics Data System (ADS)

    Brattkus, K.; Davis, S. H.

    1991-02-01

    The linear-stability theory of plane stagnation-point flow against an infinite flat plate is re-examined. Disturbances are generalized from those of Goertler type to include other types of variations along the plate. It is shown that Hiemenz flow is linearly stable and that the Goertler-type modes are those that decay slowest. This work then rationalizes the use of such self-similar disturbances on Hiemenz flow and shows how questions of disturbance structure can be approached on other self-similar flows.

  5. The linear stability of plane stagnation-point flow against general disturbances

    NASA Technical Reports Server (NTRS)

    Brattkus, K.; Davis, S. H.

    1991-01-01

    The linear-stability theory of plane stagnation-point flow against an infinite flat plate is re-examined. Disturbances are generalized from those of Goertler type to include other types of variations along the plate. It is shown that Hiemenz flow is linearly stable and that the Goertler-type modes are those that decay slowest. This work then rationalizes the use of such self-similar disturbances on Hiemenz flow and shows how questions of disturbance structure can be approached on other self-similar flows.

  6. Profile Detection in Medical and Astronomical Images by Means of the Hough Transform of Special Classes of Curves

    NASA Astrophysics Data System (ADS)

    Massone, A. M.; Perasso, A.; Campi, C.; Beltrametti, M. C.

    2015-02-01

    We develop a formal procedure for the automated recognition of rational and elliptic curves in medical and astronomical images. The procedure is based on the extension of the Hough transform concept to the definition of Hough transform of special classes of algebraic curves. We first introduce a catalogue of curves that satisfy the conditions to be automatically extracted from an image and the recognition algorithm, then we illustrate the power of this method to identify skeleton profiles in clinical X-ray tomography maps and front ends of solar eruptions in astronomical images provided by the NASA solar dynamics observatory satellite.

  7. K2 Mission Light Curves

    NASA Astrophysics Data System (ADS)

    Smith, Jeffrey C.; morris, robert; Bryson, Steve; Jenkins, Jon Michael; Caldwell, Douglas

    2015-08-01

    The K2 mission is now generating light curves for its ecliptic-field campaigns. Producing good photometry for K2 is more challenging than for Kepler’s prime mission because periodic thruster firings are used to compensate for the loss of two reaction wheels. These firings, referred to as "roll tweaks", result in spacecraft rotation along the barrel axis and high corresponding image motion. The resulting motion-dominated systematic errors are dramatically different than the focus-dominated systematic errors experienced during the prime mission. They also make it challenging to properly identify and remove flux from background objects present in the optimal apertures. We summarize these challenges and describe the resulting modifications to the Kepler pipeline for the processing of K2 data. The quality of the K2 mission light curves is characterized.

  8. Infinite swapping in curved spaces

    NASA Astrophysics Data System (ADS)

    Curotto, E.; Mella, Massimo

    2014-01-01

    We develop an extension of the infinite swapping and partial infinite swapping techniques [N. Plattner, J. D. Doll, P. Dupuis, H. Wang, Y. Liu, and J. E. Gubernatis, J. Chem. Phys. 135, 134111 (2011)] to curved spaces. Furthermore, we test the performance of infinite swapping and partial infinite swapping in a series of flat spaces characterized by the same potential energy surface model. We develop a second order variational algorithm for general curved spaces without the extended Lagrangian formalism to include holonomic constraints. We test the new methods by carrying out NVT classical ensemble simulations on a set of multidimensional toroids mapped by stereographic projections and characterized by a potential energy surface built from a linear combination of decoupled double wells shaped purposely to create rare events over a range of temperatures.

  9. Infinite swapping in curved spaces.

    PubMed

    Curotto, E; Mella, Massimo

    2014-01-07

    We develop an extension of the infinite swapping and partial infinite swapping techniques [N. Plattner, J. D. Doll, P. Dupuis, H. Wang, Y. Liu, and J. E. Gubernatis, J. Chem. Phys. 135, 134111 (2011)] to curved spaces. Furthermore, we test the performance of infinite swapping and partial infinite swapping in a series of flat spaces characterized by the same potential energy surface model. We develop a second order variational algorithm for general curved spaces without the extended Lagrangian formalism to include holonomic constraints. We test the new methods by carrying out NVT classical ensemble simulations on a set of multidimensional toroids mapped by stereographic projections and characterized by a potential energy surface built from a linear combination of decoupled double wells shaped purposely to create rare events over a range of temperatures.

  10. Analysis of Exoplanet Light Curves

    NASA Astrophysics Data System (ADS)

    Erdem, A.; Budding, E.; Rhodes, M. D.; Püsküllü, Ç.; Soydugan, F.; Soydugan, E.; Tüysüz, M.; Demircan, O.

    2015-07-01

    We have applied the close binary system analysis package WINFITTER to a variety of exoplanet transiting light curves taken both from the NASA Exoplanet Archive and our own ground-based observations. WINFitter has parameter options for a realistic physical model, including gravity brightening and structural parameters derived from Kopal's applications of the relevant Radau equation, and it includes appropriate tests for determinacy and adequacy of its best fitting parameter sets. We discuss a number of issues related to empirical checking of models for stellar limb darkening, surface maculation, Doppler beaming, microvariability, and transit time variation (TTV) effects. The Radau coefficients used in the light curve modeling, in principle, allow structural models of the component stars to be tested.

  11. Analysis of growing crack tip deformation using both in-plane deformation and caustics obtained from out-of-plane displacement

    SciTech Connect

    Luo, P.F.; Wang, J.S.; Chao, Y.J.; Sutton, M.A.

    1996-12-31

    The stereo vision is used to study the fracture behavior in the compact tension (CT) specimen made from 304L stainless steel. During crack tip blunting, initiation, and growth in the CT specimen, both in-plane and out-of-plane displacement fields near the crack tip are measured by the stereo vision. Based on the plane stress assumption and the deformation theory of plasticity, the J integral is evaluated along several rectangular paths surrounding the crack tip by using the measured in-plane displacement field. Prior to crack growth, the J integral is path independent. For crack extension up to {Delta}a {approx} 3 mm, the near field J integral values are 6% to 10% lower than far field J integral values. For the crack extension of {Delta}a {approx} 4 mm, the J integral lost path independence. The far field J integral values are in good agreement with results obtained from Merkle-Corten`s formula. Both J-{Delta}a and CTOA-{Delta}a are obtained by computing the J integral value and crack tip opening angle (CTOA) at each {Delta}a. Results indicate that CTOA reached a nearly constant value at a crack extension of {Delta}a = 3 mm with a leveled resistance curve thereafter. Also, the J integral value is determined by the maximum transverse diameter of the shadow spots, which are generated by using the out-of-plane displacement field. Results indicate that for crack extension up to 0.25 mm, the J integral values evaluated by using the out-of- plane displacement are close to those obtained by using in-plane displacements and Merkle-Corten`s formula.

  12. Accelerating Around an Unbanked Curve

    NASA Astrophysics Data System (ADS)

    Mungan, Carl E.

    2006-02-01

    The December 2004 issue of TPT presented a problem concerning how a car should accelerate around an unbanked curve of constant radius r starting from rest if it is to avoid skidding. Interestingly enough, two solutions were proffered by readers.2 The purpose of this note is to compare and contrast the two approaches. Further experimental investigation of various turning strategies using a remote-controlled car and overhead video analysis could make for an interesting student project.

  13. A two-axis in-plane motion measurement system based on optical beam deflection

    SciTech Connect

    Sriramshankar, R.; Mrinalini, R. Sri Muthu; Jayanth, G. R.

    2013-10-15

    Measurement of in-plane motion with high resolution and large bandwidth enables model-identification and real-time control of motion-stages. This paper presents an optical beam deflection based system for measurement of in-plane motion of both macro- and micro-scale motion stages. A curved reflector is integrated with the motion stage to achieve sensitivity to in-plane translational motion along two axes. Under optimal settings, the measurement system is shown to theoretically achieve sub-angstrom measurement resolution over a bandwidth in excess of 1 kHz and negligible cross-sensitivity to linear motion. Subsequently, the proposed technique is experimentally demonstrated by measuring the in-plane motion of a piezo flexure stage and a scanning probe microcantilever. For the former case, reflective spherical balls of different radii are employed to measure the in-plane motion and the measured sensitivities are shown to agree with theoretical values, on average, to within 8.3%. For the latter case, a prototype polydimethylsiloxane micro-reflector is integrated with the microcantilever. The measured in-plane motion of the microcantilever probe is used to identify nonlinearities and the transient dynamics of the piezo-stage upon which the probe is mounted. These are subsequently compensated by means of feedback control.

  14. Failure Criteria for FRP Laminates in Plane Stress

    NASA Technical Reports Server (NTRS)

    Davila, Carlos G.; Camanho, Pedro P.

    2003-01-01

    A new set of six failure criteria for fiber reinforced polymer laminates is described. Derived from Dvorak's fracture mechanics analyses of cracked plies and from Puck's action plane concept, the physically-based criteria, denoted LaRC03, predict matrix and fiber failure accurately without requiring curve-fitting parameters. For matrix failure under transverse compression, the fracture plane is calculated by maximizing the Mohr-Coulomb effective stresses. A criterion for fiber kinking is obtained by calculating the fiber misalignment under load, and applying the matrix failure criterion in the coordinate frame of the misalignment. Fracture mechanics models of matrix cracks are used to develop a criterion for matrix in tension and to calculate the associated in-situ strengths. The LaRC03 criteria are applied to a few examples to predict failure load envelopes and to predict the failure mode for each region of the envelope. The analysis results are compared to the predictions using other available failure criteria and with experimental results. Predictions obtained with LaRC03 correlate well with the experimental results.

  15. Geometric and analytic problems on bicomplex plane

    NASA Astrophysics Data System (ADS)

    Dimiev, Stancho; Stoev, Peter; Stoilova, Stanislava

    2015-11-01

    Let us recall that the bicomplex plane is a complex ring of complex dimension 2. It consists of couples of the kind (z, w) = z + jw, where z and w are complex numbers and j is a symbol with the property j2 = -1. We note that the bicomplex plane admits singular points. The set of these singular points coincides with the cross-choped set of complex bisectrices (z, ±z), z is a complex. The main problem in the function theory on the bicomplex plane is to describe the interconnection between the same theory of the cross-choped subset and whole bicomplex plane. The first theory is of one complex variable and the second one is of two complex variables. Another problems are related with the comformal mappings and the movement of a partials of this subset on the whole one. Presented paper is a start studies in this direction.

  16. Attitude analysis in Flatland: The plane truth

    NASA Technical Reports Server (NTRS)

    Shuster, Malcolm D.

    1993-01-01

    Many results in attitude analysis are still meaningful when the attitude is restricted to rotations about a single axis. Such a picture corresponds to attitude analysis in the Euclidean plane. The present report formalizes the representation of attitude in the plane and applies it to some well-known problems. In particular, we study the connection of the 'additive' and 'multiplicative' formulations of the differential corrector for the quaternion in its two-dimensional setting.

  17. Local convexity-preserving C2 rational cubic spline for convex data.

    PubMed

    Abbas, Muhammad; Abd Majid, Ahmad; Ali, Jamaludin Md

    2014-01-01

    We present the smooth and visually pleasant display of 2D data when it is convex, which is contribution towards the improvements over existing methods. This improvement can be used to get the more accurate results. An attempt has been made in order to develop the local convexity-preserving interpolant for convex data using C(2) rational cubic spline. It involves three families of shape parameters in its representation. Data dependent sufficient constraints are imposed on single shape parameter to conserve the inherited shape feature of data. Remaining two of these shape parameters are used for the modification of convex curve to get a visually pleasing curve according to industrial demand. The scheme is tested through several numerical examples, showing that the scheme is local, computationally economical, and visually pleasing.

  18. Computational Methods Applied to Rational Drug Design.

    PubMed

    Ramírez, David

    2016-01-01

    Due to the synergic relationship between medical chemistry, bioinformatics and molecular simulation, the development of new accurate computational tools for small molecules drug design has been rising over the last years. The main result is the increased number of publications where computational techniques such as molecular docking, de novo design as well as virtual screening have been used to estimate the binding mode, site and energy of novel small molecules. In this work I review some tools, which enable the study of biological systems at the atomistic level, providing relevant information and thereby, enhancing the process of rational drug design.

  19. Laboratory Evaluation of Australian Ration Packs

    DTIC Science & Technology

    1993-08-01

    Procurement of CRIM 11 2.2.2 Controlled Storage Conditions 11 2.2.3 Ration Chocolate 12 2.2.4 Data Collection and Interpretation 12 2.3 Analytical...Fortified Chocolate Trial 21 3.1.3 Ascorbyl Palmitate Fortified Chocolate Trial 21 3.1.4 IMCR Main Meal Trial 21 3.1.5 CRIOM Soup Powder Trial 21... chocolate and coffee for the storage stability of ascorbic acid and hiamine. "* EFR fruit candy for the storage stability of ascorbic acid. "* Combat

  20. Rational design and synthesis of Janus composites.

    PubMed

    Liang, Fuxin; Zhang, Chengliang; Yang, Zhenzhong

    2014-10-29

    Janus composites with two different components divided on the same object have gained growing interest in many fields, such as solid emulsion stabilizers, sensors, optical probes and self-propellers. Over the past twenty years, various synthesis methods have been developed including Pickering emulsion interfacial modification, block copolymer self-assembly, microfluidics, electro co-jetting, and swelling emulsion polymerization. Anisotropic shape and asymmetric spatial distribution of compositions and functionalities determine their unique performances. Rational design and large scale synthesis of functional Janus materials are crucial for the systematical characterization of performance and exploitation of practical applications.

  1. Computational Methods Applied to Rational Drug Design

    PubMed Central

    Ramírez, David

    2016-01-01

    Due to the synergic relationship between medical chemistry, bioinformatics and molecular simulation, the development of new accurate computational tools for small molecules drug design has been rising over the last years. The main result is the increased number of publications where computational techniques such as molecular docking, de novo design as well as virtual screening have been used to estimate the binding mode, site and energy of novel small molecules. In this work I review some tools, which enable the study of biological systems at the atomistic level, providing relevant information and thereby, enhancing the process of rational drug design. PMID:27708723

  2. Rational defect introduction in silicon nanowires.

    PubMed

    Shin, Naechul; Chi, Miaofang; Howe, Jane Y; Filler, Michael A

    2013-05-08

    The controlled introduction of planar defects, particularly twin boundaries and stacking faults, in group IV nanowires remains challenging despite the prevalence of these structural features in other nanowire systems (e.g., II-VI and III-V). Here we demonstrate how user-programmable changes to precursor pressure and growth temperature can rationally generate both transverse twin boundaries and angled stacking faults during the growth of <111> oriented Si nanowires. We leverage this new capability to demonstrate prototype defect superstructures. These findings yield important insight into the mechanism of defect generation in semiconductor nanowires and suggest new routes to engineer the properties of this ubiquitous semiconductor.

  3. Reverse engineering of complex biological body parts by squared distance enabled non-uniform rational B-spline technique and layered manufacturing.

    PubMed

    Pandithevan, Ponnusamy

    2015-02-01

    In tissue engineering, the successful modeling of scaffold for the replacement of damaged body parts depends mainly on external geometry and internal architecture in order to avoid the adverse effects such as pain and lack of ability to transfer the load to the surrounding bone. Due to flexibility in controlling the parameters, layered manufacturing processes are widely used for the fabrication of bone tissue engineering scaffold with the given computer-aided design model. This article presents a squared distance minimization approach for weight optimization of non-uniform rational B-spline curve and surface to modify the geometry that exactly fits into the defect region automatically and thus to fabricate the scaffold specific to subject and site. The study showed that though the errors associated in the B-spline curve and surface were minimized by squared distance method than point distance method and tangent distance method, the errors could be minimized further in the rational B-spline curve and surface as the optimal weight could change the shape that desired for the defect site. In order to measure the efficacy of the present approach, the results were compared with point distance method and tangent distance method in optimizing the non-rational and rational B-spline curve and surface fitting for the defect site. The optimized geometry then allowed to construct the scaffold in fused deposition modeling system as an example. The result revealed that the squared distance-based weight optimization of the rational curve and surface in making the defect specific geometry best fits into the defect region than the other methods used.

  4. Spatial Reasoning Training Through Light Curves Of Model Asteroids

    NASA Astrophysics Data System (ADS)

    Ziffer, Julie; Nakroshis, Paul A.; Rudnick, Benjamin T.; Brautigam, Maxwell J.; Nelson, Tyler W.

    2015-11-01

    Recent research has demonstrated that spatial reasoning skills, long known to be crucial to math and science success, are teachable. Even short stints of training can improve spatial reasoning skills among students who lack them (Sorby et al., 2006). Teaching spatial reasoning is particularly valuable to women and minorities who, through societal pressure, often doubt their spatial reasoning skill (Hill et al., 2010). We have designed a hands on asteroid rotation lab that provides practice in spatial reasoning tasks while building the student’s understanding of photometry. For our tool, we mount a model asteroid, with any shape of our choosing, on a slowly rotating motor shaft, whose speed is controlled by the experimenter. To mimic an asteroid light curve, we place the model asteroid in a dark box, shine a movable light source upon our asteroid, and record the light reflected onto a moveable camera. Students may then observe changes in the light curve that result from varying a) the speed of rotation, b) the model asteroid’s orientation with respect to the motor axis, c) the model asteroid’s shape or albedo, and d) the phase angle. After practicing with our tool, students are asked to pair new objects to their corresponding light curves. To correctly pair objects to their light curves, students must imagine how light scattering off of a three dimensional rotating object is imaged on a ccd sensor plane, and then reduced to a series of points on a light curve plot. Through the use of our model asteroid, the student develops confidence in spatial reasoning skills.

  5. Rational Decision-Making in Inhibitory Control

    PubMed Central

    Shenoy, Pradeep; Yu, Angela J.

    2011-01-01

    An important aspect of cognitive flexibility is inhibitory control, the ability to dynamically modify or cancel planned actions in response to changes in the sensory environment or task demands. We formulate a probabilistic, rational decision-making framework for inhibitory control in the stop signal paradigm. Our model posits that subjects maintain a Bayes-optimal, continually updated representation of sensory inputs, and repeatedly assess the relative value of stopping and going on a fine temporal scale, in order to make an optimal decision on when and whether to go on each trial. We further posit that they implement this continual evaluation with respect to a global objective function capturing the various reward and penalties associated with different behavioral outcomes, such as speed and accuracy, or the relative costs of stop errors and go errors. We demonstrate that our rational decision-making model naturally gives rise to basic behavioral characteristics consistently observed for this paradigm, as well as more subtle effects due to contextual factors such as reward contingencies or motivational factors. Furthermore, we show that the classical race model can be seen as a computationally simpler, perhaps neurally plausible, approximation to optimal decision-making. This conceptual link allows us to predict how the parameters of the race model, such as the stopping latency, should change with task parameters and individual experiences/ability. PMID:21647306

  6. Ritual and rational action in hospitals.

    PubMed

    Chapman, G E

    1983-01-01

    Menzies argues that nursing hierarchies and ritual practices protect nurses from the anxieties provoked by encountering human suffering. This proposition is examined with particular reference to ritual practices in nursing. It is argued that Menzies studied nurses in isolation from the societal and subcultural norms and values which direct hospital activity. Her psychodynamic model is contrasted with a sociological model of human conduct and action. The characteristics of ritual and rational action, and the difference between non-rational and irrational rituals, is explored. The findings of three 5-month periods of participant observation are presented as illustrative case material to support the authors view, that ritual procedures are not only defence mechanisms against anxiety, but social acts which generate and convey meaning. Ritual practices described in this analysis include rituals surrounding birth, death, status and power. It is concluded that if nurses wish to change or alter ritual nursing practices in hospital it is necessary to understand their social as well as their psychological meaning.

  7. Liberal rationalism and medical decision-making.

    PubMed

    Savulescu, Julian

    1997-04-01

    I contrast Robert Veatch's recent liberal vision of medical decision-making with a more rationalist liberal model. According to Veatch, physicians are biased in their determination of what is in their patient's overall interests in favour of their medical interests. Because of the extent of this bias, we should abandon the practice of physicians offering what they guess to be the best treatment option. Patients should buddy up with physicians who share the same values -- 'deep value pairing'. The goal of choice is maximal promotion of patient values. I argue that if subjectivism about value and valuing is true, this move is plausible. However, if objectivism about value is true -- that there really are states which are good for people regardless of whether they desire to be in them -- then we should accept a more rationalist liberal alternative. According to this alternative, what is required to decide which course is best is rational dialogue between physicians and patients, both about the patient's circumstances and her values, and not the seeking out of people, physicians or others, who share the same values. Rational discussion requires that physicians be reasonable and empathic. I describe one possible account of a reasonable physician.

  8. Of Models and Machines: Implementing Bounded Rationality.

    PubMed

    Dick, Stephanie

    2015-09-01

    This essay explores the early history of Herbert Simon's principle of bounded rationality in the context of his Artificial Intelligence research in the mid 1950s. It focuses in particular on how Simon and his colleagues at the RAND Corporation translated a model of human reasoning into a computer program, the Logic Theory Machine. They were motivated by a belief that computers and minds were the same kind of thing--namely, information-processing systems. The Logic Theory Machine program was a model of how people solved problems in elementary mathematical logic. However, in making this model actually run on their 1950s computer, the JOHNNIAC, Simon and his colleagues had to navigate many obstacles and material constraints quite foreign to the human experience of logic. They crafted new tools and engaged in new practices that accommodated the affordances of their machine, rather than reflecting the character of human cognition and its bounds. The essay argues that tracking this implementation effort shows that "internal" cognitive practices and "external" tools and materials are not so easily separated as they are in Simon's principle of bounded rationality--the latter often shaping the dynamics of the former.

  9. Rational recovery: alternative to AA for addiction?

    PubMed

    Galanter, M; Egelko, S; Edwards, H

    1993-01-01

    Rational Recovery (RR) is a new self-help movement for substance abusers, with a cognitive orientation. It has been suggested as an alternative to Alcoholics Anonymous. This study was designed to examine the nature of RR and its impact on those who join. A national sample of 433 substance-abusing people attending 63 established RR groups was evaluated, using codable self-report questionnaires completed at RR meetings. Members were mostly men with college experience who had previously attended AA. Among recruits who attended their first RR meeting in the last month, 38% were abstinent in the last month. Among members who had joined 3 or more months before, 73% were abstinent in the last month; they had attended an average of 4.1 RR meetings in that month, and carried out exercises at home based on Rational Emotive Therapy. Among those who joined 6 or more months before, 58% reported at least 6 months of abstinence. Among members with a history of heavy cocaine use, the portion reporting abstinence in the last month was not significantly different from those who had never used cocaine. The minority of members who were engaged for 3 months were still drinking, though, and did so on an average of 9.9 days in the last month. RR succeeded in engaging substance abusers and promoting abstinence among many of them while presenting a cognitive orientation that is different from the spiritual one of AA. Its utility in substance abuse treatment warrants further assessment.

  10. Scattering in three dimensions from rational maps

    NASA Astrophysics Data System (ADS)

    Cachazo, Freddy; He, Song; Yuan, Ellis Ye

    2013-10-01

    The complete tree-level S-matrix of four dimensional super Yang-Mills and supergravity has compact forms as integrals over the moduli space of certain rational maps. In this note we derive formulas for amplitudes in three dimensions by using the fact that when amplitudes are dressed with proper wave functions dimensional reduction becomes straightforward. This procedure leads to formulas in terms of rational maps for three dimensional maximally supersymmetric Yang-Mills and gravity theories. The integrand of the new formulas contains three basic structures: Parke-Taylor-like factors, Vandermonde determinants and resultants. Integrating out some of the Grassmann directions produces formulas for theories with less than maximal supersymmetry, which exposes yet a fourth kind of structure. Combining all four basic structures we start a search for consistent S-matrices in three dimensions. Very nicely, the most natural ones are those corresponding to ABJM and BLG theories. We also make a connection between the power of a resultant in the integrand, representations of the Poincaré group, infrared behavior and conformality of a theory. Extensions to other theories in three dimensions and to arbitrary dimensions are also discussed.

  11. Compression of contour data through exploiting curve-to-curve dependence

    NASA Technical Reports Server (NTRS)

    Yalabik, N.; Cooper, D. B.

    1975-01-01

    An approach to exploiting curve-to-curve dependencies in order to achieve high data compression is presented. One of the approaches to date of along curve compression through use of cubic spline approximation is taken and extended by investigating the additional compressibility achievable through curve-to-curve structure exploitation. One of the models under investigation is reported on.

  12. m-plane GaN layers grown by rf-plasma assisted molecular beam epitaxy with varying Ga/N flux ratios on m-plane 4H-SiC substrates

    SciTech Connect

    Armitage, R.; Horita, M.; Suda, J.; Kimoto, T.

    2007-02-01

    A series of m-plane GaN layers with the Ga beam-equivalent pressure (BEP) as the only varied parameter was grown by rf-plasma assisted molecular beam epitaxy on m-plane 4H-SiC substrates using AlN buffer layers. The smoothest growth surfaces and most complete film coalescence were found for the highest Ga BEP corresponding to the Ga droplet accumulation regime. However, better structural quality as assessed by x-ray rocking curves was observed for growth at a lower Ga BEP value below the droplet limit. The variation of rocking curve widths for planes inclined with respect to the epilayer c axis followed a different trend with Ga BEP than those of reflections parallel to the c axis. The GaN layers were found to exhibit a large residual compressive strain along the a axis.

  13. NLINEAR - NONLINEAR CURVE FITTING PROGRAM

    NASA Technical Reports Server (NTRS)

    Everhart, J. L.

    1994-01-01

    A common method for fitting data is a least-squares fit. In the least-squares method, a user-specified fitting function is utilized in such a way as to minimize the sum of the squares of distances between the data points and the fitting curve. The Nonlinear Curve Fitting Program, NLINEAR, is an interactive curve fitting routine based on a description of the quadratic expansion of the chi-squared statistic. NLINEAR utilizes a nonlinear optimization algorithm that calculates the best statistically weighted values of the parameters of the fitting function and the chi-square that is to be minimized. The inputs to the program are the mathematical form of the fitting function and the initial values of the parameters to be estimated. This approach provides the user with statistical information such as goodness of fit and estimated values of parameters that produce the highest degree of correlation between the experimental data and the mathematical model. In the mathematical formulation of the algorithm, the Taylor expansion of chi-square is first introduced, and justification for retaining only the first term are presented. From the expansion, a set of n simultaneous linear equations are derived, which are solved by matrix algebra. To achieve convergence, the algorithm requires meaningful initial estimates for the parameters of the fitting function. NLINEAR is written in Fortran 77 for execution on a CDC Cyber 750 under NOS 2.3. It has a central memory requirement of 5K 60 bit words. Optionally, graphical output of the fitting function can be plotted. Tektronix PLOT-10 routines are required for graphics. NLINEAR was developed in 1987.

  14. Double plane wave reverse time migration with plane wave Green's function

    NASA Astrophysics Data System (ADS)

    Zhao, Z.; Sen, M. K.; Stoffa, P. L.

    2015-12-01

    Reverse time migration (RTM) is effective in obtaining complex subsurface structures from seismic data. By solving the two-way wave equation, RTM can use entire wavefield for imaging. Although powerful computer are becoming available, the conventional pre-stack shot gather RTM is still computationally expensive. Solving forward and backward wavefield propagation for each source location and shot gather is extremely time consuming, especially for large seismic datasets. We present an efficient, accurate and flexible plane wave RTM in the frequency domain where we utilize a compressed plane wave dataset, known as the double plane wave (DPW) dataset. Provided with densely sampled seismic dataset, shot gathers can be decomposed into source and receiver plane wave components with minimal artifacts. The DPW RTM is derived under the Born approximation and utilizes frequency domain plane wave Green's function for imaging. Time dips in the shot profiles can help to estimate the range of plane wave components present in shot gathers. Therefore, a limited number of plane wave Green's functions are needed for imaging. Plane wave Green's functions can be used for imaging both source and receiver plane waves. Source and receiver reciprocity can be used for imaging plane wave components at no cost and save half of the computation time. As a result, the computational burden for migration is substantially reduced. Plane wave components can be migrated independently to recover specific targets with given dips, and ray parameter common image gathers (CIGs) can be generated after migration directly. The ray parameter CIGs can be used to justify the correctness of velocity models. Subsurface anisotropy effects can also be included in our imaging condition, provided with plane wave Green's functions in the anisotropic media.

  15. Biomechanical differences between incline and plane hopping.

    PubMed

    Kannas, Theodoros M; Kellis, Eleftherios; Amiridis, Ioannis G

    2011-12-01

    Kannas, TM, Kellis, E, and Amiridis, IG. Biomechanical differences between incline and plane hopping. J Strength Cond Res 25(12): 3334-3341, 2011-The need for the generation of higher joint power output during performance of dynamic activities led us to investigate the force-length relationship of the plantar flexors during consecutive stretch-shortening cycles of hopping. The hypothesis of this study was that hopping (consecutive jumps with the knee as straight as possible) on an inclined (15°) surface might lead to a better jumping performance compared with hopping on a plane surface (0°). Twelve active men performed 3 sets of 10 consecutive hops on both an incline and plane surface. Ground reaction forces; ankle and knee joint kinematics; electromyographic (EMG) activity from the medial gastrocnemius (MG), soleus (Sol) and tibialis anterior (TA); and architectural data from the MG were recorded. The results showed that participants jumped significantly higher (p < 0.05) when hopping on an inclined surface (30.32 ± 8.18 cm) compared with hopping on a plane surface (27.52 ± 4.97 cm). No differences in temporal characteristics between the 2 types of jumps were observed. Incline hopping induced significantly greater ankle dorsiflexion and knee extension at takeoff compared with plane hopping (p < 0.05). The fascicle length of the MG was greater at initial contact with the ground during incline hopping (p < 0.05). Moreover, the EMG activities of Sol and TA during the propulsion phase were significantly higher during incline compared with that during plane hopping (p < 0.05). It does not seem unreasonable to suggest that, if the aim of hopping plyometrics is to improve plantar flexor explosivity, incline hopping might be a more effective exercise than hopping on a plane surface.

  16. Sound propagation over curved barriers

    NASA Technical Reports Server (NTRS)

    Pierce, Allan D.; Main, Geoffrey L.; Kearns, James A.; Hsieh, H.-A.

    1986-01-01

    Wide barriers with curved tops are studied with emphasis placed on circumstances whereby the local radius of curvature R of the barrier is continuous along the surface and is large compared to a wavelength. Results analogous to those given by Hayek et al. (1978) are reviewed and extended to cases where the radius of curvature and the surface impedance may vary with position. Circumstances not easily interpreted within the framework of the model proposed by Keller (1956) and Hayek et al. are also considered.

  17. Sound propagation over curved barriers

    NASA Astrophysics Data System (ADS)

    Pierce, Allan D.; Main, Geoffrey L.; Kearns, James A.; Hsieh, H.-A.

    Wide barriers with curved tops are studied with emphasis placed on circumstances whereby the local radius of curvature R of the barrier is continuous along the surface and is large compared to a wavelength. Results analogous to those given by Hayek et al. (1978) are reviewed and extended to cases where the radius of curvature and the surface impedance may vary with position. Circumstances not easily interpreted within the framework of the model proposed by Keller (1956) and Hayek et al. are also considered.

  18. Dirac's aether in curved spacetime.

    PubMed

    Oliveira; Teixeira

    2000-06-01

    Proca's equations for two types of fields in a Dirac's aether with electric conductivity sigma are solved exactly. The Proca electromagnetic fields are assumed with cylindrical symmetry. The background is a static, curved spacetime whose spatial section is homogeneous and has the topology of either the three-sphere S 3 or the projective three-space P 3. Simple relations between the range of Proca field lambda, the Universe radius R, the limit of photon rest mass mgamma and the conductivity sigma are written down.

  19. Curved microchannels and bacterial streamers

    NASA Astrophysics Data System (ADS)

    Rusconi, Roberto; Lecuyer, Sigolene; Guglielmini, Laura; Stone, Howard

    2010-03-01

    Bacterial biofilms are commonly identified as microbial communities attached to a surface and encased in a self-secreted extracellular matrix. Due to their increased resistance to antimicrobial agents, biofilms have an enormous impact on health and medicine (e.g., wound healing, implant-associated infections, disease transmission). On the other hand, they constitute a major component of the stream ecosystem by increasing transport of nutrients and retention of suspended particles. In this talk, we present an experimental study of bacterial biofilm development in a microfluidic device. In particular, we show the formation of filamentous structures, or streamers, in curved channels and how these suspended biofilms are linked to the underlying hydrodynamics.

  20. Extension of the angular spectrum method to calculate pressure from a spherically curved acoustic source.

    PubMed

    Vyas, Urvi; Christensen, Douglas A

    2011-11-01

    The angular spectrum method is an accurate and computationally efficient method for modeling acoustic wave propagation. The use of the typical 2D fast Fourier transform algorithm makes this a fast technique but it requires that the source pressure (or velocity) be specified on a plane. Here the angular spectrum method is extended to calculate pressure from a spherical transducer-as used extensively in applications such as magnetic resonance-guided focused ultrasound surgery-to a plane. The approach, called the Ring-Bessel technique, decomposes the curved source into circular rings of increasing radii, each ring a different distance from the intermediate plane, and calculates the angular spectrum of each ring using a Fourier series. Each angular spectrum is then propagated to the intermediate plane where all the propagated angular spectra are summed to obtain the pressure on the plane; subsequent plane-to-plane propagation can be achieved using the traditional angular spectrum method. Since the Ring-Bessel calculations are carried out in the frequency domain, it reduces calculation times by a factor of approximately 24 compared to the Rayleigh-Sommerfeld method and about 82 compared to the Field II technique, while maintaining accuracies of better than 96% as judged by those methods for cases of both solid and phased-array transducers.

  1. INTERIOR OF SECOND FLOOR BRIDGE BETWEEN PLANING MILL AND CAR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR OF SECOND FLOOR BRIDGE BETWEEN PLANING MILL AND CAR MACHINE SHOP, LOOKING SOUTH TOWARD PLANING MILL. - Southern Pacific, Sacramento Shops, Planing Mill, 111 I Street, Sacramento, Sacramento County, CA

  2. GLAMER - II. Multiple-plane gravitational lensing

    NASA Astrophysics Data System (ADS)

    Petkova, Margarita; Metcalf, R. Benton; Giocoli, Carlo

    2014-12-01

    We present an extension to multiple planes of the gravitational lensing code GLAMER. The method entails projecting the mass in the observed light-cone on to a discrete number of lens planes and inverse ray-shooting from the image to the source plane. The mass on each plane can be represented as haloes, simulation particles, a projected mass map extracted form a numerical simulation or any combination of these. The image finding is done in a source-oriented fashion, where only regions of interest are iteratively refined on an initially coarse image plane grid. The calculations are performed in parallel on shared memory machines. The code is able to handle different types of analytic haloes (NFW, NSIE, power law, etc.), haloes extracted from numerical simulations and clusters constructed from semi-analytic models (MOKA). Likewise, there are several different options for modelling the source(s) which can be distributed throughout the light-cone. The distribution of matter in the light-cone can be either taken from a pre-existing N-body numerical simulations, from halo catalogues, or are generated from an analytic mass function. We present several tests of the code and demonstrate some of its applications such as generating mock images of galaxy and galaxy cluster lenses.

  3. Focal Plane Metrology for the LSST Camera

    SciTech Connect

    A Rasmussen, Andrew P.; Hale, Layton; Kim, Peter; Lee, Eric; Perl, Martin; Schindler, Rafe; Takacs, Peter; Thurston, Timothy; /SLAC

    2007-01-10

    Meeting the science goals for the Large Synoptic Survey Telescope (LSST) translates into a demanding set of imaging performance requirements for the optical system over a wide (3.5{sup o}) field of view. In turn, meeting those imaging requirements necessitates maintaining precise control of the focal plane surface (10 {micro}m P-V) over the entire field of view (640 mm diameter) at the operating temperature (T {approx} -100 C) and over the operational elevation angle range. We briefly describe the hierarchical design approach for the LSST Camera focal plane and the baseline design for assembling the flat focal plane at room temperature. Preliminary results of gravity load and thermal distortion calculations are provided, and early metrological verification of candidate materials under cold thermal conditions are presented. A detailed, generalized method for stitching together sparse metrology data originating from differential, non-contact metrological data acquisition spanning multiple (non-continuous) sensor surfaces making up the focal plane, is described and demonstrated. Finally, we describe some in situ alignment verification alternatives, some of which may be integrated into the camera's focal plane.

  4. Miniature curved artificial compound eyes

    PubMed Central

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L’Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A.; Franceschini, Nicolas

    2013-01-01

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories. PMID:23690574

  5. Improved capacitive melting curve measurements

    NASA Astrophysics Data System (ADS)

    Sebedash, Alexander; Tuoriniemi, Juha; Pentti, Elias; Salmela, Anssi

    2009-02-01

    Sensitivity of the capacitive method for determining the melting pressure of helium can be enhanced by loading the empty side of the capacitor with helium at a pressure nearly equal to that desired to be measured and by using a relatively thin and flexible membrane in between. This way one can achieve a nanobar resolution at the level of 30 bar, which is two orders of magnitude better than that of the best gauges with vacuum reference. This extends the applicability of melting curve thermometry to lower temperatures and would allow detecting tiny anomalies in the melting pressure, which must be associated with any phenomena contributing to the entropy of the liquid or solid phases. We demonstrated this principle in measurements of the crystallization pressure of isotopic helium mixtures at millikelvin temperatures by using partly solid pure 4He as the reference substance providing the best possible universal reference pressure. The achieved sensitivity was good enough for melting curve thermometry on mixtures down to 100 μK. Similar system can be used on pure isotopes by virtue of a blocked capillary giving a stable reference condition with liquid slightly below the melting pressure in the reference volume. This was tested with pure 4He at temperatures 0.08-0.3 K. To avoid spurious heating effects, one must carefully choose and arrange any dielectric materials close to the active capacitor. We observed some 100 pW loading at moderate excitation voltages.

  6. Wrinkling Crystallography on Curved Surfaces

    NASA Astrophysics Data System (ADS)

    Reis, Pedro; Brojan, Miha; Terwagne, Denis; Lagrange, Romain

    2014-03-01

    We present results on an experimental analysis of the morphology of wrinkling patterns on curved surfaces. Our experimental hemispherical samples are fabricated using rapid prototyping and consist of a thin-stiff shell adhered to a soft-thick substrate, both made out of silicone-based rubbers. Pressurizing an inner spherical air cavity enables compression of the samples, thereby morphing the outer thin shell from its initially smooth configuration into a wrinkled state. A variety of patterns with different morphologies can be observed depending on the combination of the sample's geometric and material properties. We focus our attention on the specific pattern mode of hexagonal-like dimples, which we characterize by analyzing their surface profile using a digital 3D scanner. Through digital image processing, we skeletonize these patterns by identifying both the location of the ridges and determining the positions of the dimples. We give emphasis to the effect of curvature on the morphology and topology of these wrinkled patterns and focus on the tiling of the wrinkling units and their statistics of defects. Our results are contrasted with other crystalline planar and curved systems.

  7. Miniature curved artificial compound eyes.

    PubMed

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L'Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A; Franceschini, Nicolas

    2013-06-04

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories.

  8. Method of non-destructively inspecting a curved wall portion

    DOEpatents

    Fong, James T.

    1996-01-01

    A method of non-destructively inspecting a curved wall portion of a large and thick walled vessel for a defect by computed tomography is provided. A collimated source of radiation is placed adjacent one side of the wall portion and an array of detectors for the radiation is placed on the other side adjacent the source. The radiation from the source passing through the wall portion is then detected with the detectors over a limited angle, dependent upon the curvature of the wall of the vessel, to obtain a dataset. The source and array are then coordinately moved relative to the wall portion in steps and a further dataset is obtained at each step. The plurality of datasets obtained over the limited angle is then processed to produce a tomogram of the wall portion to determine the presence of a defect therein. In a preferred embodiment, the curved wall portion has a center of curvature so that the source and the array are positioned at each step along a respective arc curved about the center. If desired, the detector array and source can be reoriented relative to a new wall portion and an inspection of the new wall portion can be easily obtained. Further, the source and detector array can be indexed in a direction perpendicular to a plane including the limited angle in a plurality of steps so that by repeating the detecting and moving steps at each index step, a three dimensional image can be created of the wall portion.

  9. Skyrmion vibration modes within the rational map ansatz

    SciTech Connect

    Lin, W. T.; Piette, B.

    2008-06-15

    We study the vibration modes of the Skyrme model within the rational map ansatz. We show that the vibrations of the radial profiles and the rational maps are decoupled and we consider explicitly the cases B=1, B=2, and B=4. We then compare our results with the vibration modes obtained numerically by Barnes et al. and show that qualitatively the rational map reproduces the vibration modes obtained numerically but that the vibration frequencies of these modes do not match very well.

  10. Point Shifts in Rational Interpolation with Optimized Denominator

    DTIC Science & Technology

    2001-07-01

    estimate hr - f’Ik. and hr - f"Il. Schneider and Werner [14] have noticed that every rational interpolant R E lZNN, written in its barycentric form R...UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP013753 TITLE: Point Shifts in Rational Interpolation with Optimized...report: ADP013708 thru ADP013761 UNCLASSIFIED Point shifts in rational interpolation with optimized denominator Jean-Paul Berrut D~partement de

  11. The MSX Galactic Plane Survey Submillimeter Results

    NASA Astrophysics Data System (ADS)

    Price, S.; Carey, S.; Egan, M. P.

    The MidCourse Space eXperiment (MSX) surveyed the Galactic plane within 5° latitude in four mid-infrared spectral bands. A set of full resolution (20'') 1.5^circ×1.5^circ images on 6'' pixel centers has been created in each spectral band by co-adding all the survey data. A lower (1.2') resolution atlas of 10^circ×10^circ images provide large-scale panoramas of the plane. A new class of objects has been identified in the images, infrared dark clouds, which are silhouetted against the mid-infrared background emission from the interstellar medium in the Galactic plane. The IRAS ISSA plates indicate that these clouds are dark out to 100 μm. Submillimeter emission traces the form of the dark cloud and reveals cores indicative of class 0 protostars.

  12. Out of plane analysis for composite structures

    NASA Technical Reports Server (NTRS)

    Paul, P. C.; Saff, C. R.; Sanger, Kenneth B.; Mahler, M. A.; Kan, Han Pin; Kautz, Edward F.

    1990-01-01

    Simple two dimensional analysis techniques were developed to aid in the design of strong joints for integrally stiffened/bonded composite structures subjected to out of plane loads. It was found that most out of plane failures were due to induced stresses arising from rapid changes in load path direction or geometry, induced stresses due to changes in geometry caused by buckling, or direct stresses produced by fuel pressure or bearing loads. While the analysis techniques were developed to address a great variety of out of plane loading conditions, they were primarily derived to address the conditions described above. The methods were developed and verified using existing element test data. The methods were demonstrated using the data from a test failure of a high strain wingbox that was designed, built, and tested under a previous program. Subsequently, a set of design guidelines were assembled to assist in the design of safe, strong integral composite structures using the analysis techniques developed.

  13. Update on rational targeted therapy in AML

    PubMed Central

    Shafer, Danielle; Grant, Steven

    2016-01-01

    Acute myeloid leukemia (AML) remains a challenge to both patients and clinicians. Despite improvements in our understanding of the disease, treatment has changed minimally and outcomes remain poor for the majority of patients. Within the last decade, there have been an increasing number of potential targets and pathways identified for development in AML. The classes of agents described in this review include but are not limited to epigenetic modifiers such as IDH inhibitors, BET inhibitors, and HDAC inhibitors as well as cell cycle and signaling inhibitors such as Aurora kinase inhibitors and CDK inhibitors. While the developments are encouraging, it is unlikely that targeting a single pathway will result in long-term disease control. Accordingly, we will also highlight potential rational partners for the novel agents described herein. PMID:26972558

  14. Rational elicitation of cold-sensitive phenotypes

    PubMed Central

    Baliga, Chetana; Majhi, Sandipan; Mondal, Kajari; Bhattacharjee, Antara; Varadarajan, Raghavan

    2016-01-01

    Cold-sensitive phenotypes have helped us understand macromolecular assembly and biological phenomena, yet few attempts have been made to understand the basis of cold sensitivity or to elicit it by design. We report a method for rational design of cold-sensitive phenotypes. The method involves generation of partial loss-of-function mutants, at either buried or functional sites, coupled with selective overexpression strategies. The only essential input is amino acid sequence, although available structural information can be used as well. The method has been used to elicit cold-sensitive mutants of a variety of proteins, both monomeric and dimeric, and in multiple organisms, namely Escherichia coli, Saccharomyces cerevisiae, and Drosophila melanogaster. This simple, yet effective technique of inducing cold sensitivity eliminates the need for complex mutations and provides a plausible molecular mechanism for eliciting cold-sensitive phenotypes. PMID:27091994

  15. Rationalization of some genetic anticodonic assignments

    NASA Technical Reports Server (NTRS)

    Lacey, J. C., Jr.; Hall, L. M.; Mullins, D. W., Jr.

    1985-01-01

    The hydrophobicity of most amino acids correlates well with that of their anticodon nucleotides, with Trp, Tyr, Ile, and Ser being the exceptions to this rule. Using previous data on hydrophobicity and binding constants, and new data on rates of esterification of polyadenylic acid with several N-acetylaminoacyl imidazolides, several of the anticodon assignments are rationalized. Chemical reasons are shown supporting the idea of the inclusion of the Ile in the catalog of biological amino acids late in the evolution, through a mutation of the existing tRNA and its aminoacyl-tRNA-synthetase. It was found that an addition of hexane increases the incorporation of hydrophobic Ac-Phe into poly-A, in support of the Fox (1965) and Oparin (1965) emphasis on the biogenetic importance of phase-separated systems.

  16. Rational design of class I MHC ligands

    NASA Astrophysics Data System (ADS)

    Rognan, D.; Scapozza, L.; Folkers, G.; Daser, Angelika

    1995-04-01

    From the knowledge of the three-dimensional structure of a class I MHC protein, several non natural peptides were designed in order to either optimize the interactions of one secondary anchor amino acid with its HLA binding pocket or to substitute the non interacting part with spacer residues. All peptides were synthesized and tested for binding to the class I MHC protein in an in vitro reconstitution assay. As predicted, the non natural peptides present an enhanced binding to the HLA-B27 molecule with respect to their natural parent peptides. This study constitutes the first step towards the rational design of non peptidic MHC ligands that should be very promising tools for the selective immunotherapy of autoimmune diseases.

  17. Update on rational targeted therapy in AML.

    PubMed

    Shafer, Danielle; Grant, Steven

    2016-07-01

    Acute myeloid leukemia (AML) remains a challenge to both patients and clinicians. Despite improvements in our understanding of the disease, treatment has changed minimally and outcomes remain poor for the majority of patients. Within the last decade, there have been an increasing number of potential targets and pathways identified for development in AML. The classes of agents described in this review include but are not limited to epigenetic modifiers such as IDH inhibitors, BET inhibitors, and HDAC inhibitors as well as cell cycle and signaling inhibitors such as Aurora kinase inhibitors and CDK inhibitors. While the developments are encouraging, it is unlikely that targeting a single pathway will result in long-term disease control. Accordingly, we will also highlight potential rational partners for the novel agents described herein.

  18. Rational Design of Biobetters with Enhanced Stability.

    PubMed

    Courtois, Fabienne; Schneider, Curtiss P; Agrawal, Neeraj J; Trout, Bernhardt L

    2015-08-01

    Biotherapeutics are the fastest growing class of pharmaceutical with a rapidly evolving market facing the rise of biosimilar and biobetter products. In contrast to a biosimilar, which is derived from the same gene sequence as the innovator product, a biobetter has enhanced properties, such as enhanced efficacy or reduced immunogenicity. Little work has been carried out so far to increase the intrinsic stability of biotherapeutics via sequence changes, even though, aggregation, the primary degradation pathway of proteins, leads to issues ranging from manufacturing failure to immunological response and to loss of therapeutic activity. Using our spatial aggregation propensity tool as a first step to a rational design approach to identify aggregation-prone regions, biobetters of rituximab have been produced with enhanced stability by introducing site-specific mutations. Significant stabilization against aggregation was achieved for rituximab with no decrease in its binding affinity to the antigen.

  19. An appraisal of rational-emotive therapy.

    PubMed

    Haaga, D A; Davison, G C

    1993-04-01

    Albert Ellis's rational-emotive therapy (RET) is scrutinized on several conceptual and empirical grounds, including its reliance on constructive assessment and its ethical stance. Its professional impact thus far exceeds its scientific status. Opinion varies on how even to define irrational beliefs; 1 consequence is problems in assessing them. Meta-analytic reviews provide support for the general utility of RET, but more qualitative reviews question both the internal and external validity of much of the published research. Lacking are process studies that can shed light on the mechanisms of therapeutic change, a situation likely due to the complexity of RET and to a lack of consensus as well about its very definition. Perhaps more progress can be achieved by forsaking studies of RET as a package and shifting instead to examination of specific therapeutic tactics in particular circumstances.

  20. Achromatic phase shifting focal plane masks

    NASA Astrophysics Data System (ADS)

    Newman, Kevin

    The search for life on other worlds is an exciting scientific endeavor that could change the way we perceive our place in the universe. Thousands of extrasolar planets have been discovered using indirect detection techniques. One of the most promising methods for discovering new exoplanets and searching for life is direct imaging with a coronagraph. Exoplanet coronagraphy of Earth-like planets is a challenging task, but we have developed many of the tools necessary to make it feasible. The Phase-Induced Amplitude Apodization (PIAA) Coronagraph is one of the highest-performing architectures for direct exoplanet imaging. With a complex phase-shifting focal plane mask, the PIAA Complex Mask Coronagraph (PIAACMC) can approach the theoretical performance limit for any direct detection technique. The architecture design is flexible enough to be applied to any arbitrary aperture shape, including segmented and obscured apertures. This is an important feature for compatibility with next-generation ground and space-based telescopes. PIAA and PIAACMC focal plane masks have been demonstrated in monochromatic light. An important next step for high-performance coronagraphy is the development of broadband phase-shifting focal plane masks. In this dissertation, we present an algorithm for designing the PIAA and PIAACMC focal plane masks to operate in broadband. We also demonstrate manufacturing of the focal plane masks, and show laboratory results. We use simulations to show the potential performance of the coronagraph system, and the use of wavefront control to correct for mask manufacturing errors. Given the laboratory results and simulations, we show new areas of exoplanet science that can potentially be explored using coronagraph technology. The main conclusion of this dissertation is that we now have the tools required to design and manufacture PIAA and PIAACMC achromatic focal plane masks. These tools can be applied to current and future telescope systems to enable new

  1. Flipping and scooping of curved 2D rigid fibers in simple shear: The Jeffery equations

    NASA Astrophysics Data System (ADS)

    Crowdy, Darren

    2016-05-01

    The dynamical system governing the motion of a curved rigid two-dimensional circular-arc fiber in simple shear is derived in analytical form. This is achieved by finding the solution for the associated low-Reynolds-number flow around such a fiber using the methods of complex analysis. Solutions of the dynamical system display the "flipping" and "scooping" recently observed in computational studies of three-dimensional fibers using linked rigid rod and bead-shell models [J. Wang et al., "Flipping, scooping, and spinning: Drift of rigid curved nonchiral fibers in simple shear flows," Phys. Fluids 24, 123304 (2012)]. To complete the Jeffery-type equations for a curved fiber in a linear flow field we also derive its evolution equations in an extensional flow. It is expected that the equations derived here also govern the motion of slender, curved, three-dimensional rigid fibers when they evolve purely in the plane of shear or strain.

  2. Nondestructive method and apparatus for imaging grains in curved surfaces of polycrystalline articles

    DOEpatents

    Carpenter, Donald A.

    1995-01-01

    A nondestructive method, and associated apparatus, are provided for determining the grain flow of the grains in a convex curved, textured polycrystalline surface. The convex, curved surface of a polycrystalline article is aligned in a horizontal x-ray diffractometer and a monochromatic, converging x-ray beam is directed onto the curved surface of the polycrystalline article so that the converging x-ray beam is diffracted by crystallographic planes of the grains in the polycrystalline article. The diffracted x-ray beam is caused to pass through a set of horizontal, parallel slits to limit the height of the beam and thereafter. The linear intensity of the diffracted x-ray is measured, using a linear position sensitive proportional counter, as a function of position in a direction orthogonal to the counter so as to generate two dimensional data. An image of the grains in the curved surface of the polycrystalline article is provided based on the two-dimensional data.

  3. Correspondence in damage phenomena and R-curve behavior in ceramics and geomaterials using moire interferometry

    NASA Astrophysics Data System (ADS)

    Perry, Kenneth E.; Epstein, Jonathan S.; May, G. B.; Shull, J. L.

    1991-12-01

    At certain grain sizes, alumina R curves have been shown to increase with crack growth. This phenomenon is in contrast to R curves for metals, which exhibit a steady-state plateau effect with increasing crack growth. Recent results show R curves for calcium silicate geomaterials also increase. The specimen geometry employed for both alumina and geomaterials is a generalized plane stress double cantilever beam (DCB). The specimens are under direct pin loading with fixed displacement. This note will discuss the common mechanisms of increasing R curve behavior of these quasi brittle materials. Finally, a hypothesis on the discrepancy between the fracture toughness of single crack rock samples and in large seismic events is presented.

  4. Cyborg pantocrator: international relations theory from decisionism to rational choice.

    PubMed

    Guilhot, Nicolas

    2011-01-01

    International relations theory took shape in the 1950s in reaction to the behavioral social science movement, emphasizing the limits of rationality in a context of high uncertainty, weak rules, and the possibility of lethal conflict. Yet the same discipline rapidly developed "rational choice" models applied to foreign policy decision making or nuclear strategy. This paper argues that this transformation took place almost seamlessly around the concept of "decision." Initially associated with an antirationalist or "decisionist" approach to politics, the sovereign decision became the epitome of political rationality when it was redescribed as "rational choice," thus easing the cultural acceptance of political realism in the postwar years.

  5. Structural anisotropic properties of a-plane GaN epilayers grown on r-plane sapphire by molecular beam epitaxy

    SciTech Connect

    Lotsari, A.; Kehagias, Th.; Katsikini, M.; Arvanitidis, J.; Ves, S.; Komninou, Ph.; Dimitrakopulos, G. P.; Tsiakatouras, G.; Tsagaraki, K.; Georgakilas, A.; Christofilos, D.

    2014-06-07

    Heteroepitaxial non-polar III-Nitride layers may exhibit extensive anisotropy in the surface morphology and the epilayer microstructure along distinct in-plane directions. The structural anisotropy, evidenced by the “M”-shape dependence of the (112{sup ¯}0) x-ray rocking curve widths on the beam azimuth angle, was studied by combining transmission electron microscopy observations, Raman spectroscopy, high resolution x-ray diffraction, and atomic force microscopy in a-plane GaN epilayers grown on r-plane sapphire substrates by plasma-assisted molecular beam epitaxy (PAMBE). The structural anisotropic behavior was attributed quantitatively to the high dislocation densities, particularly the Frank-Shockley partial dislocations that delimit the I{sub 1} intrinsic basal stacking faults, and to the concomitant plastic strain relaxation. On the other hand, isotropic samples exhibited lower dislocation densities and a biaxial residual stress state. For PAMBE growth, the anisotropy was correlated to N-rich (or Ga-poor) conditions on the surface during growth, that result in formation of asymmetric a-plane GaN grains elongated along the c-axis. Such conditions enhance the anisotropy of gallium diffusion on the surface and reduce the GaN nucleation rate.

  6. Slant plane CSAR processing using Householder transform.

    PubMed

    Burki, Jehanzeb; Barnes, Christopher F

    2008-10-01

    Fourier analysis-based focusing of synthetic aperture radar (SAR) data collected during circular flight path is a recent advancement in SAR signal processing. This paper uses the Householder transform to obtain a ground plane circular SAR (CSAR) signal phase history from the slant plane CSAR phase history by inverting the linear shift-varying system model, thereby circumventing the need for explicitly computing a pseudo-inverse. The Householder transform has recently been shown to have improved error bounds and stability as an underdetermined and ill-conditioned system solver, and the Householder transform is computationally efficient.

  7. [Normolipemic plane xanthomas and mycosis fungoides].

    PubMed

    García-Arpa, Mónica; Rodríguez-Vázquez, María; Vera, Elena; Romero, Guillermo; González-García, Jesús; Cortina, Pilar

    2005-06-01

    Diffuse normolipemic plane xanthomas are characterized by the presence of yellowish plaques on the eyelids, neck, upper trunk, buttocks and flexures. Histology shows foamy histiocytes in the dermis. Approximately half of all cases are associated with hematological disorders. On rare occasions, they have been described in the context of cutaneous T-cell lymphomas. We present the case of a female patient with tumor-stage mycosis fungoides who developed normolipemic plane xanthomas coinciding with the appearance of new lymphoma lesions. We review English-language literature regarding the rare association of xanthomas and cutaneous T-cell lymphomas.

  8. Toward loop quantization of plane gravitational waves

    NASA Astrophysics Data System (ADS)

    Hinterleitner, Franz; Major, Seth

    2012-03-01

    The polarized Gowdy model in terms of Ashtekar-Barbero variables is reduced with an additional constraint derived from the Killing equations for plane gravitational waves with parallel rays. The new constraint is formulated in a diffeomorphism invariant manner and, when it is included in the model, the resulting constraint algebra is first class, in contrast to the prior work done in special coordinates. Using an earlier work by Banerjee and Date, the constraints are expressed in terms of classical quantities that have an operator equivalent in loop quantum gravity, making these plane gravitational wave spacetimes accessible to loop quantization techniques.

  9. Orbital plane change maneuver with aerocruise

    NASA Astrophysics Data System (ADS)

    Naidu, D. S.

    1991-01-01

    The synergistic plane change problem connected with orbital transfer employing aeroassist technology, is addressed. The mission involves transfer from high earth orbit to low earth orbit with plane change being performed within the atmosphere. The complete mission consists of a deorbit phase, atmospheric phase, and finally reorbit phase. The atmospheric maneuver is composed of an entry mode, a cruise mode, and finally an exit mode. During the cruise mode, constant altitude and velocity are maintained by means of bank angle control with constant thrust or thrust control with constant bank angle. Comparisons between these two control strategies bring out some interesting features.

  10. The Aggregate Demand Curve: A Reply.

    ERIC Educational Resources Information Center

    Hansen, Richard B.; And Others

    1987-01-01

    Responds to claims about the instructional value of the downward-sloping aggregate demand curve in teaching principles of macroeconomics. Examines the effects of interest-rates and the role of money on demand curves. Concludes by arguing against the use of downward-sloping aggregate demand curves in textbooks. (RKM)

  11. Cubic spline functions for curve fitting

    NASA Technical Reports Server (NTRS)

    Young, J. D.

    1972-01-01

    FORTRAN cubic spline routine mathematically fits curve through given ordered set of points so that fitted curve nearly approximates curve generated by passing infinite thin spline through set of points. Generalized formulation includes trigonometric, hyperbolic, and damped cubic spline fits of third order.

  12. Note: A novel integrated microforce measurement system for plane-plane contact research

    NASA Astrophysics Data System (ADS)

    Dong, W.; Rostoucher, D.; Gauthier, M.

    2010-11-01

    The evaluation of plane-plane contact force has become a big issue in micro-/nano research, for example in microassembly. However with the lack of effective experimental equipments, the research on plane-plane contact has been limited to theoretical formulations or virtual simulation. In this paper, a microforce sensor and precision parallel robot integrated system is proposed for the microforce measurement of plane-plane contact. In the proposed system, the two objects are fixed on the parallel robot end-platform and the microforce sensor probe tip, respectively, and the high precision robot system is employed to provide six degree-of-freedom motions between both objects. So it is convenient for the microforce measurement between the planar objects with different orientations. As a significant application, the proposed system is utilized for measurements of pull-off force between planar objects, in which the validation of the system is demonstrated in practice. The proposed microforce measurement system is generic, which can be extended to a variety of microforce measurements in plane-plane contact.

  13. Hemispherical infrared focal plane arrays: a new design parameter for the instruments

    NASA Astrophysics Data System (ADS)

    Fendler, M.; Dumas, D.; Chemla, F.; Cohen, M.; Laporte, P.; Tekaya, K.; Le Coarer, E.; Primot, J.; Ribot, H.

    2012-07-01

    In ground based astronomy, mainly all designs of sky survey telescopes are limited by the requirement that the detecting surface is flat whereas the focal surface is curved. Two kinds of solution have been investigated up to now. The first one consists in adding optical systems to flatten the image surface; however this solution complicates the design and increases the system size. Somehow, this solution increases, in the same time, the weight and price of the instrument. The second solution consists in curving artificially the focal surface by using a mosaic of several detectors, which are positioned in a spherical shape. However, this attempt is dedicated to low curvature and is limited by the technical difficulty to control the detectors alignment and tilt between each others. Today we would like to propose an ideal solution which is to curve the focal plane array in a spherical shape, thanks to our monolithic process developed at CEA-LETI based on thinned silicon substrates which allows a 100% optical fill factor. Two infrared uncooled cameras have been performed, using 320 x 256 pixels and 25 μm pitch micro-bolometer arrays curved at a bending radius of 80 mm. These two micro-cameras illustrate the optical system simplification and miniaturization involved by curved focal plane arrays. Moreover, the advantages of curved detectors on the optical performances (Point Spreading Function), as well as on volume and cost savings have been highlighted by the simulation of the opto-mechanical architecture of the spectrometer OptiMOS-EVE for the European Extremely Large Telescope (E-ELT).

  14. Curved film cooling admission tube

    NASA Technical Reports Server (NTRS)

    Graham, R. W.; Papell, S. S. (Inventor)

    1980-01-01

    Effective film cooling to protect a wall surface from a hot fluid which impinges on or flows along the surface is provided. A film of cooling fluid having increased area is provided by changing the direction of a stream of cooling fluid through an angle of from 135 deg. to 165 deg. before injecting it through the wall into the hot flowing gas. The 1, cooling fluid is injected from an orifice through a wall into a hot flowing gas at an angle to form a cooling fluid film. Cooling fluid is supplied to the orifice from a cooling fluid source via a turbulence control passageway having a curved portion between two straight portions. The angle through which the direction of the cooling fluid is turned results in less mixing of the cooling fluid with the hot gas, thereby substantially increasing the length of the film in a downstream direction.

  15. Laser-induced magnetization curve

    NASA Astrophysics Data System (ADS)

    Takayoshi, Shintaro; Sato, Masahiro; Oka, Takashi

    2014-12-01

    We propose an all optical ultrafast method to highly magnetize general quantum magnets using a circularly polarized terahertz laser. The key idea is to utilize a circularly polarized laser and its chirping. Through this method, one can obtain magnetization curves of a broad class of quantum magnets as a function of time even without any static magnetic field. We numerically demonstrate the laser-induced magnetization process in realistic quantum spin models and find a condition for the realization. The onset of magnetization can be described by a many-body version of Landau-Zener mechanism. In a particular model, we show that a plateau state with topological properties can be realized dynamically.

  16. Caloric curve of star clusters.

    PubMed

    Casetti, Lapo; Nardini, Cesare

    2012-06-01

    Self-gravitating systems, such as globular clusters or elliptical galaxies, are the prototypes of many-body systems with long-range interactions, and should be the natural arena in which to test theoretical predictions on the statistical behavior of long-range-interacting systems. Systems of classical self-gravitating particles can be studied with the standard tools of equilibrium statistical mechanics, provided the potential is regularized at small length scales and the system is confined in a box. The confinement condition looks rather unphysical in general, so that it is natural to ask whether what we learn with these studies is relevant to real self-gravitating systems. In order to provide an answer to this question, we consider a basic, simple, yet effective model of globular clusters: the King model. This model describes a self-consistently confined system, without the need of any external box, but the stationary state is a nonthermal one. In particular, we consider the King model with a short-distance cutoff on the interactions, and we discuss how such a cutoff affects the caloric curve, i.e., the relation between temperature and energy. We find that the cutoff stabilizes a low-energy phase, which is absent in the King model without cutoff; the caloric curve of the model with cutoff turns out to be very similar to that of previously studied confined and regularized models, but for the absence of a high-energy gaslike phase. We briefly discuss the possible phenomenological as well as theoretical implications of these results.

  17. Caloric curve of star clusters

    NASA Astrophysics Data System (ADS)

    Casetti, Lapo; Nardini, Cesare

    2012-06-01

    Self-gravitating systems, such as globular clusters or elliptical galaxies, are the prototypes of many-body systems with long-range interactions, and should be the natural arena in which to test theoretical predictions on the statistical behavior of long-range-interacting systems. Systems of classical self-gravitating particles can be studied with the standard tools of equilibrium statistical mechanics, provided the potential is regularized at small length scales and the system is confined in a box. The confinement condition looks rather unphysical in general, so that it is natural to ask whether what we learn with these studies is relevant to real self-gravitating systems. In order to provide an answer to this question, we consider a basic, simple, yet effective model of globular clusters: the King model. This model describes a self-consistently confined system, without the need of any external box, but the stationary state is a nonthermal one. In particular, we consider the King model with a short-distance cutoff on the interactions, and we discuss how such a cutoff affects the caloric curve, i.e., the relation between temperature and energy. We find that the cutoff stabilizes a low-energy phase, which is absent in the King model without cutoff; the caloric curve of the model with cutoff turns out to be very similar to that of previously studied confined and regularized models, but for the absence of a high-energy gaslike phase. We briefly discuss the possible phenomenological as well as theoretical implications of these results.

  18. AKLSQF - LEAST SQUARES CURVE FITTING

    NASA Technical Reports Server (NTRS)

    Kantak, A. V.

    1994-01-01

    The Least Squares Curve Fitting program, AKLSQF, computes the polynomial which will least square fit uniformly spaced data easily and efficiently. The program allows the user to specify the tolerable least squares error in the fitting or allows the user to specify the polynomial degree. In both cases AKLSQF returns the polynomial and the actual least squares fit error incurred in the operation. The data may be supplied to the routine either by direct keyboard entry or via a file. AKLSQF produces the least squares polynomial in two steps. First, the data points are least squares fitted using the orthogonal factorial polynomials. The result is then reduced to a regular polynomial using Sterling numbers of the first kind. If an error tolerance is specified, the program starts with a polynomial of degree 1 and computes the least squares fit error. The degree of the polynomial used for fitting is then increased successively until the error criterion specified by the user is met. At every step the polynomial as well as the least squares fitting error is printed to the screen. In general, the program can produce a curve fitting up to a 100 degree polynomial. All computations in the program are carried out under Double Precision format for real numbers and under long integer format for integers to provide the maximum accuracy possible. AKLSQF was written for an IBM PC X/AT or compatible using Microsoft's Quick Basic compiler. It has been implemented under DOS 3.2.1 using 23K of RAM. AKLSQF was developed in 1989.

  19. In plane oscillation of a bifilar pendulum

    NASA Astrophysics Data System (ADS)

    Hinrichsen, Peter F.

    2016-11-01

    The line tensions, the horizontal and vertical accelerations as well as the period of large angle oscillations parallel to the plane of a bifilar suspension are presented and have been experimentally investigated using strain gauges and a smart phone. This system has a number of advantages over the simple pendulum for studying large angle oscillations, and for measuring the acceleration due to gravity.

  20. MTI Focal Plane Assembly Design and Performance

    SciTech Connect

    Ballard, M.; Rienstra, J.L.

    1999-06-17

    The focal plane assembly for the Multispectral Thermal Imager (MTI) consists of sensor chip assemblies, optical filters, and a vacuum enclosure. Sensor chip assemblies, composed of linear detector arrays and readout integrated circuits, provide spatial resolution in the cross-track direction for the pushbroom imager. Optical filters define 15 spectral bands in a range from 0.45 {micro}m to 10.7 {micro}m. All the detector arrays are mounted on a single focal plane and are designed to operate at 75 K. Three pairs of sensor chip assemblies (SCAs) are required to provide cross-track coverage in all 15 spectral bands. Each pair of SCAs includes detector arrays made from silicon, iridium antimonide, and mercury cadmium telluride. Read out integrated circuits multiplex the signals from the detectors to 18 separate video channels. Optical filter assemblies defining the spectral bands are mounted over the linear detector arrays. Each filter assembly consists of several filter strips bonded together side-by-side. The MTI focal plane assembly has been integrated with the rest of the payload and has undergone detailed testing and calibration. This paper includes representative test data for the various spectral bands and the overall performance of the focal plane assembly.

  1. Plane Smoothers for Multiblock Grids: Computational Aspects

    NASA Technical Reports Server (NTRS)

    Llorente, Ignacio M.; Diskin, Boris; Melson, N. Duane

    1999-01-01

    Standard multigrid methods are not well suited for problems with anisotropic discrete operators, which can occur, for example, on grids that are stretched in order to resolve a boundary layer. One of the most efficient approaches to yield robust methods is the combination of standard coarsening with alternating-direction plane relaxation in the three dimensions. However, this approach may be difficult to implement in codes with multiblock structured grids because there may be no natural definition of global lines or planes. This inherent obstacle limits the range of an implicit smoother to only the portion of the computational domain in the current block. This report studies in detail, both numerically and analytically, the behavior of blockwise plane smoothers in order to provide guidance to engineers who use block-structured grids. The results obtained so far show alternating-direction plane smoothers to be very robust, even on multiblock grids. In common computational fluid dynamics multiblock simulations, where the number of subdomains crossed by the line of a strong anisotropy is low (up to four), textbook multigrid convergence rates can be obtained with a small overlap of cells between neighboring blocks.

  2. Deep-Plane Lipoabdominoplasty in East Asians

    PubMed Central

    Jang, Jun-Young; Hong, Yoon Gi; Sim, Hyung Bo; Sun, Sang Hoon

    2016-01-01

    Background The objective of this study was to develop a new surgical technique by combining traditional abdominoplasty with liposuction. This combination of operations permits simpler and more accurate management of various abdominal deformities. In lipoabdominoplasty, the combination of techniques is of paramount concern. Herein, we introduce a new combination of liposuction and abdominoplasty using deep-plane flap sliding to maximize the benefits of both techniques. Methods Deep-plane lipoabdominoplasty was performed in 143 patients between January 2007 and May 2014. We applied extensive liposuction on the entire abdomen followed by a sliding flap through the deep plane after repairing the diastasis recti. The abdominal wound closure was completed with repair of Scarpa's fascia. Results The average amount of liposuction aspirate was 1,400 mL (700–3,100 mL), and the size of the average excised skin ellipse was 21.78×12.81 cm (from 15×10 to 25×15 cm). There were no major complications such as deep-vein thrombosis or pulmonary embolism. We encountered 22 cases of minor complications: one wound infection, one case of skin necrosis, two cases of undercorrection, nine hypertrophic scars, and nine seromas. These complications were solved by conservative management or simple revision. Conclusions The use of deep-plane lipoabdominoplasty can correct abdominal deformities more effectively and with fewer complications than traditional abdominoplasty. PMID:27462568

  3. Microscale out-of-plane anemometer

    NASA Technical Reports Server (NTRS)

    Liu, Chang (Inventor); Chen, Jack (Inventor)

    2005-01-01

    A microscale out-of-plane thermal sensor. A resistive heater is suspended over a substrate by supports raised with respect to the substrate to provide a clearance underneath the resistive heater for fluid flow. A preferred fabrication process for the thermal sensor uses surface micromachining and a three-dimensional assembly to raise the supports and lift the resistive heater over the substrate.

  4. End Site Control Plane Subsystem (ESCPS)

    SciTech Connect

    Swany, Douglas Martin

    2014-08-12

    This project researched extending the control plane for dynamic networks into end sites like campuses and laboratories. Key aspects of consideration were signaling over local area network technologies, application integration and monitoring. We studied design considerations for such environments and developed and demonstrated a useful proof of concept implementation and documented implementation strategies for heterogeneous networks.

  5. Optical interconnections to focal plane arrays

    SciTech Connect

    Rienstra, J.L.; Hinckley, M.K.

    2000-11-01

    The authors have successfully demonstrated an optical data interconnection from the output of a focal plane array to the downstream data acquisition electronics. The demonstrated approach included a continuous wave laser beam directed at a multiple quantum well reflectance modulator connected to the focal plane array analog output. The output waveform from the optical interconnect was observed on an oscilloscope to be a replica of the input signal. They fed the output of the optical data link to the same data acquisition system used to characterize focal plane array performance. Measurements of the signal to noise ratio at the input and output of the optical interconnection showed that the signal to noise ratio was reduced by a factor of 10 or more. Analysis of the noise and link gain showed that the primary contributors to the additional noise were laser intensity noise and photodetector receiver noise. Subsequent efforts should be able to reduce these noise sources considerably and should result in substantially improved signal to noise performance. They also observed significant photocurrent generation in the reflectance modulator that imposes a current load on the focal plane array output amplifier. This current loading is an issue with the demonstrated approach because it tends to negate the power saving feature of the reflectance modulator interconnection concept.

  6. Dual band QWIP focal plane array

    NASA Technical Reports Server (NTRS)

    Gunapala, Sarath D. (Inventor); Choi, Kwong Kit (Inventor); Bandara, Sumith V. (Inventor)

    2005-01-01

    A quantum well infrared photodetector (QWIP) that provides two-color image sensing. Two different quantum wells are configured to absorb two different wavelengths. The QWIPs are arrayed in a focal plane array (FPA). The two-color QWIPs are selected for readout by selective electrical contact with the two different QWIPs or by the use of two different wavelength sensitive gratings.

  7. Simple Harmonic Motion in Harmonic Plane Waves.

    ERIC Educational Resources Information Center

    Benumof, Reuben

    1980-01-01

    Discusses the distribution of kinetic and potential energy in transverse and longitudinal waves and examines the transmission of power and momentum. This discussion is intended to aid in understanding the simple harmonic motion of a particle involved in the propagation of a harmonic mechanical plane wave. (HM)

  8. Flipping and scooping of curved 2D rigid fibers in simple shear: the Jeffery equations

    NASA Astrophysics Data System (ADS)

    Crowdy, Darren

    2015-11-01

    The dynamical system (or ``Jeffery equations'') governing the orbits of a curved rigid two-dimensional fiber in simple shear is derived in analytical form. The study is motivated by the need to understand the dynamics of isolated non-axisymmetric rod-like particles in simple flows for use in suspension modeling. Solutions of the dynamical system are shown to display the ``flipping'' and ``scooping'' recently observed in computational studies of three-dimensional fibers using linked rigid rod and bead-shell models. Indeed the equations we derive are expected to be the same ones governing curved 3D slender fibers executing motions in the plane of shear.

  9. Uniform B-Spline Curve Interpolation with Prescribed Tangent and Curvature Vectors.

    PubMed

    Okaniwa, Shoichi; Nasri, Ahmad; Lin, Hongwei; Abbas, Abdulwahed; Kineri, Yuki; Maekawa, Takashi

    2012-09-01

    This paper presents a geometric algorithm for the generation of uniform cubic B-spline curves interpolating a sequence of data points under tangent and curvature vectors constraints. To satisfy these constraints, knot insertion is used to generate additional control points which are progressively repositioned using corresponding geometric rules. Compared to existing schemes, our approach is capable of handling plane as well as space curves, has local control, and avoids the solution of the typical linear system. The effectiveness of the proposed algorithm is illustrated through several comparative examples. Applications of the method in NC machining and shape design are also outlined.

  10. Fault Plane Orientations of Intermediate-Depth Earthquakes in South America

    NASA Astrophysics Data System (ADS)

    Warren, L. M.

    2013-12-01

    Extending from Colombia in the north to Chile and Argentina in the south, the South American subduction zone exhibits considerable variation: the subduction angle alternates between flat and steep; the subducting plate has complex structures such as ridges, plateaus, and fracture zones; and late Cenozoic volcanism in the overlying plate has gaps. I investigate the effect of these differences in incoming plate structure and subduction geometry on intermediate-depth earthquakes and use the results to test hypotheses for why intermediate-depth earthquakes occur. For all large (Mw ≥5.7) intermediate-depth earthquakes (60-360 km depth) in South America since 1990, I analyze rupture directivity to try to distinguish which of the two possible fault planes of the focal mechanism slipped in the earthquake. Of the 163 earthquakes that met the selection criteria, half were recorded with a sufficient distribution of stations to determine if there was directivity to the rupture and fault planes were identified for 31 events. Fault plane orientations are spatially coherent. In regions with "normal" subduction angles, such as the Central Volcanic Zone (southern Peru to central Chile), results are consistent with previous studies in Central America and the western Pacific subduction zones: most earthquakes rupture along subhorizontal faults and rupture azimuths are randomly distributed. In the Peruvian Flat Slab, identified fault planes dip eastward. After taking into account the angle of subduction, these faults are perpendicular to the faults that rupture in regions with normal subduction angles. Within sharply curved slab segments, such as the rebending of the plate at the eastern edge of the Peruvian flat slab, both orientations of faults slip. The observed flip in dominant fault plane orientation on either side of sharply curved slab segments suggests that bending and unbending stresses have an important role in controlling fault orientations. Pre-existing weak zones may

  11. Determining the Ice-binding Planes of Antifreeze Proteins by Fluorescence-based Ice Plane Affinity

    PubMed Central

    Basu, Koli; Garnham, Christopher P.; Nishimiya, Yoshiyuki; Tsuda, Sakae; Braslavsky, Ido; Davies, Peter

    2014-01-01

    Antifreeze proteins (AFPs) are expressed in a variety of cold-hardy organisms to prevent or slow internal ice growth. AFPs bind to specific planes of ice through their ice-binding surfaces. Fluorescence-based ice plane affinity (FIPA) analysis is a modified technique used to determine the ice planes to which the AFPs bind. FIPA is based on the original ice-etching method for determining AFP-bound ice-planes. It produces clearer images in a shortened experimental time. In FIPA analysis, AFPs are fluorescently labeled with a chimeric tag or a covalent dye then slowly incorporated into a macroscopic single ice crystal, which has been preformed into a hemisphere and oriented to determine the a- and c-axes. The AFP-bound ice hemisphere is imaged under UV light to visualize AFP-bound planes using filters to block out nonspecific light. Fluorescent labeling of the AFPs allows real-time monitoring of AFP adsorption into ice. The labels have been found not to influence the planes to which AFPs bind. FIPA analysis also introduces the option to bind more than one differently tagged AFP on the same single ice crystal to help differentiate their binding planes. These applications of FIPA are helping to advance our understanding of how AFPs bind to ice to halt its growth and why many AFP-producing organisms express multiple AFP isoforms. PMID:24457629

  12. Studying Quality beyond Technical Rationality: Political and Symbolic Perspectives

    ERIC Educational Resources Information Center

    Blanco Ramírez, Gerardo

    2013-01-01

    The underlying paradigms that influence research on quality have remained alarmingly under-researched; this article analyses the constraints that a technical-rational approach for the study of quality in higher education imposes. Technical rationality has been the dominant paradigm that shapes research on quality in higher education.…

  13. Early Developmental Trajectories toward Concepts of Rational Numbers

    ERIC Educational Resources Information Center

    Kainulainen, Mikko; McMullen, Jake; Lehtinen, Erno

    2017-01-01

    Difficulties with rational numbers have been explained by a natural number bias, where concepts of natural numbers are inappropriately applied to rational numbers. Overcoming this difficulty may require a radical restructuring of previous knowledge. In order to capture this development, we examined third- to fifth-grade students' understanding of…

  14. Imagination and the Pursuit of a Rational Rhetoric.

    ERIC Educational Resources Information Center

    Foster, David E.

    The works of certain rhetorical thinkers contain strategies directed at achieving assent or cooperation. Such writings demonstrate means by which readers' rational responses can be deliberately challenged and disrupted. While people often cite Aristotle's maxim "Man is a rational animal," critics have asserted that the statement…

  15. Passionate Rationalism: The Role of Emotion in Decision Making

    ERIC Educational Resources Information Center

    Lakomski, Gabriele; Evers, Colin W.

    2010-01-01

    Purpose: The purpose of this paper is to argue that emotion has a central role to play in rational decision making based on recent research in the neuroanatomy of emotion. As a result, traditional rational decision-making theories, including Herbert Simon's modified model of satisficing that sharply demarcates emotions and values from rationality…

  16. Number Sense in the Transition from Natural to Rational Numbers

    ERIC Educational Resources Information Center

    Van Hoof, Jo; Verschaffel, Lieven; Van Dooren, Wim

    2017-01-01

    Background: Rational numbers are of critical importance both in mathematics and in other fields of science. However, they form a stumbling block for learners. One widely known source of the difficulty learners have with rational numbers is the natural number bias, that is the tendency to (inappropriately) apply natural number properties in…

  17. Rational-emotive therapy and depression: a clinical case study.

    PubMed

    Horton, A M; Johnson, C H

    1980-12-01

    Rational-emotive group and bibliotherapy were used to treat a depressed patient in a clinical setting. Psychological test data document a dramatic improvement. It is suggested that rational-emotive therapy may prove efficacious for the treatment of some depressed patients in clinical settings.

  18. Rational Emotive Behavior Therapy: Origins, Constructs, and Applications.

    ERIC Educational Resources Information Center

    Watson, Joshua C.

    In 1956, Dr. Albert Ellis presented his seminal work on Rational Therapy, subsequently renamed Rational Emotive Behavior Therapy (REBT) in 1993. This paper explores the origins, theoretical foundations, applications, and implications of REBT and provides a look at the empirical research available in support of the approach's efficacy. REBT is…

  19. Three gradients and the perception of flat and curved surfaces.

    PubMed

    Cutting, J E; Millard, R T

    1984-06-01

    Researchers of visual perception have long been interested in the perceived slant of a surface and in the gradients that purportedly specify it. Slant is the angle between the line of sight and the tangent to the planar surface at any point, also called the surface normal. Gradients are the sources of information that grade, or change, with visual angle as one looks from one's feet upward to the horizon. The present article explores three gradients--perspective, compression, and density--and the phenomenal impression of flat and curved surfaces. The perspective gradient is measured at right angles to the axis of tilt at any point in the optic array; that is, when looking down a hallway at the tiles of a floor receding in the distance, perspective is measured by the x-axis width of each tile projected on the image plane orthogonal to the line of sight. The compression gradient is the ratio of y/x axis measures on the projected plane. The density gradient is measured by the number of tiles per unit solid visual angle. For flat surfaces and many others, perspective and compression gradients decrease with distance, and the density gradient increases. We discuss the manner in which these gradients change for various types of surfaces. Each gradient is founded on a different assumption about textures on the surfaces around us. In Experiment 1, viewers assessed the three-dimensional character of projections of flat and curved surfaces receding in the distance. They made pairwise judgments of preference and of dissimilarity among eight stimuli in each of four sets. The presence of each gradient was manipulated orthogonally such that each stimulus had zero, one, two, or three gradients appropriate for either a flat surface or a curved surface. Judgments were made were made for surfaces with both regularly shaped and irregularly shaped textures scattered on them. All viewer assessment were then scaled in one dimension. Multiple correlation and regression on the scale values

  20. Validation of a personalized curved muscle model of the lumbar spine during complex dynamic exertions.

    PubMed

    Hwang, Jaejin; Knapik, Gregory G; Dufour, Jonathan S; Best, Thomas M; Khan, Safdar N; Mendel, Ehud; Marras, William S

    2017-01-09

    Previous curved muscle models have typically examined their robustness only under simple, single-plane static exertions. In addition, the empirical validation of curved muscle models through an entire lumbar spine has not been fully realized. The objective of this study was to empirically validate a personalized biologically-assisted curved muscle model during complex dynamic exertions. Twelve subjects performed a variety of complex lifting tasks as a function of load weight, load origin, and load height. Both a personalized curved muscle model as well as a straight-line muscle model were used to evaluate the model's fidelity and prediction of three-dimensional spine tissue loads under different lifting conditions. The curved muscle model showed better model performance and different spinal loading patterns through an entire lumbar spine compared to the straight-line muscle model. The curved muscle model generally showed good fidelity regardless of lifting condition. The majority of the 600 lifting tasks resulted in a coefficient of determination (R(2)) greater than 0.8 with an average of 0.83, and the average absolute error less than 15% between measured and predicted dynamic spinal moments. As expected, increased load and asymmetry were generally found to significantly increase spinal loads, demonstrating the ability of the model to differentiate between experimental conditions. A curved muscle model would be useful to estimate precise spine tissue loads under realistic circumstances. This precise assessment tool could aid in understanding biomechanical causal pathways for low back pain.

  1. Evaluation of curving characteristics of flexible liquid crystal displays fabricated using polycarbonate substrates

    NASA Astrophysics Data System (ADS)

    Sato, Akihito; Ishinabe, Takahiro; Fujikake, Hideo

    2016-01-01

    The improvement of the contrast ratio of flexible liquid crystal displays (LCDs) fabricated using plastic substrates in a curved state is an important problem to achieve high-quality flexible LCDs. In this study, we evaluated the distributions of in-plane phase retardation and slow axis direction of polycarbonate substrates and the effects of curvature on the electro-optical properties of flexible LCDs. As a result, we clarified that the polycarbonate substrates have high uniformity in the in-plane phase retardation and slow axis direction, and that the change in the phase retardation of the polycarbonate substrate caused by the curvature deformation has a small effect on the electro-optical characteristics of flexible LCDs. We successfully achieved a high contrast ratio of 1042:1 by fabricating the device using polycarbonate substrates. This result indicates that it is possible to realize high-quality images in flexible LCDs fabricated using polycarbonate substrates even in the curved state.

  2. Integrated focal-plane array /IFPA/ approach to large-area infrared focal plane architecture

    NASA Astrophysics Data System (ADS)

    Warren, R. E.

    1980-01-01

    A modular approach to IFPA design is presented which makes it possible to obtain a high-density infrared focal plane amendable to parallel manufacturing techniques as well as to serial plane integration and test. The percent fill factor of the design is dependent on the dimension of the individual detectors; each submodule is manufactured from identical components. The technologies including cables, interconnects, multilayer interconnect structures, and subassembly test requirements, which have direct application to scanning as well as staring integrated focal plane arrays, are discussed.

  3. Mate choice in fruit flies is rational and adaptive

    PubMed Central

    Arbuthnott, Devin; Fedina, Tatyana Y.; Pletcher, Scott D.; Promislow, Daniel E. L.

    2017-01-01

    According to rational choice theory, beneficial preferences should lead individuals to sort available options into linear, transitive hierarchies, although the extent to which non-human animals behave rationally is unclear. Here we demonstrate that mate choice in the fruit fly Drosophila melanogaster results in the linear sorting of a set of diverse isogenic female lines, unambiguously demonstrating the hallmark of rational behaviour, transitivity. These rational choices are associated with direct benefits, enabling males to maximize offspring production. Furthermore, we demonstrate that female behaviours and cues act redundantly in mate detection and assessment, as rational mate choice largely persists when visual or chemical sensory modalities are impaired, but not when both are impaired. Transitivity in mate choice demonstrates that the quality of potential mates varies significantly among genotypes, and that males and females behave in such a way as to facilitate adaptive mate choice. PMID:28094789

  4. On the denominator values and barycentric weights of rational interpolants

    NASA Astrophysics Data System (ADS)

    Polezzi, M.; Sri Ranga, A.

    2007-03-01

    We improve upon the method of Zhu and Zhu [A method for directly finding the denominator values of rational interpolants, J. Comput. Appl. Math. 148 (2002) 341-348] for finding the denominator values of rational interpolants, reducing considerably the number of arithmetical operations required for their computation. In a second stage, we determine the points (if existent) which can be discarded from the rational interpolation problem. Furthermore, when the interpolant has a linear denominator, we obtain a formula for the barycentric weights which is simpler than the one found by Berrut and Mittelmann [Matrices for the direct determination of the barycentric weights of rational interpolation, J. Comput. Appl. Math. 78 (1997) 355-370]. Subsequently, we give a necessary and sufficient condition for the rational interpolant to have a pole.

  5. Learning curve of speech recognition.

    PubMed

    Kauppinen, Tomi A; Kaipio, Johanna; Koivikko, Mika P

    2013-12-01

    Speech recognition (SR) speeds patient care processes by reducing report turnaround times. However, concerns have emerged about prolonged training and an added secretarial burden for radiologists. We assessed how much proofing radiologists who have years of experience with SR and radiologists new to SR must perform, and estimated how quickly the new users become as skilled as the experienced users. We studied SR log entries for 0.25 million reports from 154 radiologists and after careful exclusions, defined a group of 11 experienced radiologists and 71 radiologists new to SR (24,833 and 122,093 reports, respectively). Data were analyzed for sound file and report lengths, character-based error rates, and words unknown to the SR's dictionary. Experienced radiologists corrected 6 characters for each report and for new users, 11. Some users presented a very unfavorable learning curve, with error rates not declining as expected. New users' reports were longer, and data for the experienced users indicates that their reports, initially equally lengthy, shortened over a period of several years. For most radiologists, only minor corrections of dictated reports were necessary. While new users adopted SR quickly, with a subset outperforming experienced users from the start, identification of users struggling with SR will help facilitate troubleshooting and support.

  6. Is the tautochrone curve unique?

    NASA Astrophysics Data System (ADS)

    Terra, Pedro; de Melo e Souza, Reinaldo; Farina, C.

    2016-12-01

    We show that there are an infinite number of tautochrone curves in addition to the cycloid solution first obtained by Christiaan Huygens in 1658. We begin by reviewing the inverse problem of finding the possible potential energy functions that lead to periodic motions of a particle whose period is a given function of its mechanical energy. There are infinitely many such solutions, called "sheared" potentials. As an interesting example, we show that a Pöschl-Teller potential and the one-dimensional Morse potentials are sheared relative to one another for negative energies, clarifying why they share the same oscillation periods for their bounded solutions. We then consider periodic motions of a particle sliding without friction over a track around its minimum under the influence of a constant gravitational field. After a brief historical survey of the tautochrone problem we show that, given the oscillation period, there is an infinity of tracks that lead to the same period. As a bonus, we show that there are infinitely many tautochrones.

  7. Simulations of Closed Timelike Curves

    NASA Astrophysics Data System (ADS)

    Brun, Todd A.; Wilde, Mark M.

    2017-03-01

    Proposed models of closed timelike curves (CTCs) have been shown to enable powerful information-processing protocols. We examine the simulation of models of CTCs both by other models of CTCs and by physical systems without access to CTCs. We prove that the recently proposed transition probability CTCs (T-CTCs) are physically equivalent to postselection CTCs (P-CTCs), in the sense that one model can simulate the other with reasonable overhead. As a consequence, their information-processing capabilities are equivalent. We also describe a method for quantum computers to simulate Deutschian CTCs (but with a reasonable overhead only in some cases). In cases for which the overhead is reasonable, it might be possible to perform the simulation in a table-top experiment. This approach has the benefit of resolving some ambiguities associated with the equivalent circuit model of Ralph et al. Furthermore, we provide an explicit form for the state of the CTC system such that it is a maximum-entropy state, as prescribed by Deutsch.

  8. Novel isochronous N-body problems featuring N arbitrary rational coupling constants

    NASA Astrophysics Data System (ADS)

    Calogero, F.

    2016-07-01

    A novel class of N-body problems is identified, with N an arbitrary positive integer (N ≥ 2). These models are characterized by Newtonian ("accelerations equal forces") equations of motion describing N equal point-particles moving in the complex z-plane. These highly nonlinear equations feature N arbitrary coupling constants, yet they can be solved by algebraic operations and if all the N coupling constants are real and rational the corresponding N-body problem is isochronous: its generic solutions are all completely periodic with an overall period T independent of the initial data (but many solutions feature subperiods T/p with p integer). It is moreover shown that these models are Hamiltonian.

  9. Learning rational temporal eye movement strategies.

    PubMed

    Hoppe, David; Rothkopf, Constantin A

    2016-07-19

    During active behavior humans redirect their gaze several times every second within the visual environment. Where we look within static images is highly efficient, as quantified by computational models of human gaze shifts in visual search and face recognition tasks. However, when we shift gaze is mostly unknown despite its fundamental importance for survival in a dynamic world. It has been suggested that during naturalistic visuomotor behavior gaze deployment is coordinated with task-relevant events, often predictive of future events, and studies in sportsmen suggest that timing of eye movements is learned. Here we establish that humans efficiently learn to adjust the timing of eye movements in response to environmental regularities when monitoring locations in the visual scene to detect probabilistically occurring events. To detect the events humans adopt strategies that can be understood through a computational model that includes perceptual and acting uncertainties, a minimal processing time, and, crucially, the intrinsic costs of gaze behavior. Thus, subjects traded off event detection rate with behavioral costs of carrying out eye movements. Remarkably, based on this rational bounded actor model the time course of learning the gaze strategies is fully explained by an optimal Bayesian learner with humans' characteristic uncertainty in time estimation, the well-known scalar law of biological timing. Taken together, these findings establish that the human visual system is highly efficient in learning temporal regularities in the environment and that it can use these regularities to control the timing of eye movements to detect behaviorally relevant events.

  10. Chemogenomic approaches to rational drug design

    PubMed Central

    Rognan, D

    2007-01-01

    Paradigms in drug design and discovery are changing at a significant pace. Concomitant to the sequencing of over 180 several genomes, the high-throughput miniaturization of chemical synthesis and biological evaluation of a multiple compounds on gene/protein expression and function opens the way to global drug-discovery approaches, no more focused on a single target but on an entire family of related proteins or on a full metabolic pathway. Chemogenomics is this emerging research field aimed at systematically studying the biological effect of a wide array of small molecular-weight ligands on a wide array of macromolecular targets. Since the quantity of existing data (compounds, targets and assays) and of produced information (gene/protein expression levels and binding constants) are too large for manual manipulation, information technologies play a crucial role in planning, analysing and predicting chemogenomic data. The present review will focus on predictive in silico chemogenomic approaches to foster rational drug design and derive information from the simultaneous biological evaluation of multiple compounds on multiple targets. State-of-the-art methods for navigating in either ligand or target space will be presented and concrete drug design applications will be mentioned. PMID:17533416

  11. Biodiversity, conservation biology, and rational choice.

    PubMed

    Frank, David

    2014-03-01

    This paper critically discusses two areas of Sahotra Sarkar's recent work in environmental philosophy: biodiversity and conservation biology and roles for decision theory in incorporating values explicitly in the environmental policy process. I argue that Sarkar's emphasis on the practices of conservation biologists, and especially the role of social and cultural values in the choice of biodiversity constituents, restricts his conception of biodiversity to particular practical conservation contexts. I argue that life scientists have many reasons to measure many types of diversity, and that biodiversity metrics could be value-free. I argue that Sarkar's emphasis on the limitations of normative decision theory is in tension with his statement that decision theory can "put science and ethics together." I also challenge his claim that multi-criteria decision tools lacking axiomatic foundations in preference and utility theory are "without a rational basis," by presenting a case of a simple "outranking" multi-criteria decision rule that can violate a basic normative requirement of preferences (transitivity) and ask whether there may nevertheless be contexts in which such a procedure might assist decision makers.

  12. Boundedness of Weighted Singular Integral Operators on a Carleson Curve in Grand Lebesgue Spaces

    NASA Astrophysics Data System (ADS)

    Kokilashvili, Vakhtang; Samko, Stefan

    2010-09-01

    We obtain the necessary and sufficient conditions for the boundedness of the weighted singular integral operator with power weights in grand Lebesgue spaces. Because of applications to singular integral equations, the underlying set where the functions are defined is a Carleson curve in the complex plane. Note that weighted boundedness of an operator in grand Lebesgue space is known to be not the same as the boundedness in weighted grand Lebesgue space.

  13. Finite transformers for construction of fractal curves

    SciTech Connect

    Lisovik, L.P.

    1995-01-01

    In this paper we continue the study of infinite R{sup n}-transformers that can be used to define real functions and three-dimensional curves. An R{sup n}-transformer A generates an output n-tuple A(x) = (Y{sub 1},...,Y{sub n}), consisting of output binary representations. We have previously shown that finite R{sup n}-transformers with n = 1, 2 can be used to define a continuous, nowhere differentiable function and a Peano curve. Curves of this kind are objects of fractal geometry. Here we show that some other fractal curves, which are analogs of the Koch curve and the Sierpinski napkin, can be defined by finite R{sup 2}-transformers. R{sup n}-transformers (and also finite R{sup n}-transformers) thus provide a convenient tool for definition of fractal curves.

  14. The crack problem for a nonhomogeneous plane

    NASA Technical Reports Server (NTRS)

    Delale, F.; Erdogan, F.

    1982-01-01

    The plane elasticity problem for a nonhomogeneous medium containing a crack is considered. It is assumed that the Poisson's ratio of the medium is constant and the Young's modulus E varies exponentially with the coordinate parallel to the crack. First the half plane problem is formulated and the solution is given for arbitrary tractions along the boundary. Then the integral equation for the crack problem is derived. It is shown that the integral equation having the derivative of the crack surface displacement as the density function has a simple Cauchy type kernel. Hence, its solution and the stresses around the crack tips have the conventional square root singularity. The solution is given for various loading conditions. The results show that the effect of the Poisson's ratio and consequently that of the thickness constraint on the stress intensity factors are rather negligible.

  15. Split-field pupil plane determination apparatus

    DOEpatents

    Salmon, Joseph T.

    1996-01-01

    A split-field pupil plane determination apparatus (10) having a wedge assembly (16) with a first glass wedge (18) and a second glass wedge (20) positioned to divide a laser beam (12) into a first laser beam half (22) and a second laser beam half (24) which diverge away from the wedge assembly (16). A wire mask (26) is positioned immediately after the wedge assembly (16) in the path of the laser beam halves (22, 24) such that a shadow thereof is cast as a first shadow half (30) and a second shadow half (32) at the input to a relay telescope (14). The relay telescope (14) causes the laser beam halves (22, 24) to converge such that the first shadow half (30) of the wire mask (26) is aligned with the second shadow half (32) at any subsequent pupil plane (34).

  16. Image-plane processing of visual information

    NASA Technical Reports Server (NTRS)

    Huck, F. O.; Fales, C. L.; Park, S. K.; Samms, R. W.

    1984-01-01

    Shannon's theory of information is used to optimize the optical design of sensor-array imaging systems which use neighborhood image-plane signal processing for enhancing edges and compressing dynamic range during image formation. The resultant edge-enhancement, or band-pass-filter, response is found to be very similar to that of human vision. Comparisons of traits in human vision with results from information theory suggest that: (1) Image-plane processing, like preprocessing in human vision, can improve visual information acquisition for pattern recognition when resolving power, sensitivity, and dynamic range are constrained. Improvements include reduced sensitivity to changes in lighter levels, reduced signal dynamic range, reduced data transmission and processing, and reduced aliasing and photosensor noise degradation. (2) Information content can be an appropriate figure of merit for optimizing the optical design of imaging systems when visual information is acquired for pattern recognition. The design trade-offs involve spatial response, sensitivity, and sampling interval.

  17. Structure analysis for plane geometry figures

    NASA Astrophysics Data System (ADS)

    Feng, Tianxiao; Lu, Xiaoqing; Liu, Lu; Li, Keqiang; Tang, Zhi

    2013-12-01

    As there are increasing numbers of digital documents for education purpose, we realize that there is not a retrieval application for mathematic plane geometry images. In this paper, we propose a method for retrieving plane geometry figures (PGFs), which often appear in geometry books and digital documents. First, detecting algorithms are applied to detect common basic geometry shapes from a PGF image. Based on all basic shapes, we analyze the structural relationships between two basic shapes and combine some of them to a compound shape to build the PGF descriptor. Afterwards, we apply matching function to retrieve candidate PGF images with ranking. The great contribution of the paper is that we propose a structure analysis method to better describe the spatial relationships in such image composed of many overlapped shapes. Experimental results demonstrate that our analysis method and shape descriptor can obtain good retrieval results with relatively high effectiveness and efficiency.

  18. The iPTF Galactic Plane Survey

    NASA Astrophysics Data System (ADS)

    Bellm, Eric Christopher; Prince, Thomas A.; Miller, Adam; Kulkarni, Shrinivas R.; Kupfer, Thomas; Laher, Russ; Masci, Frank J.; Oded Ofek, Eran; Shupe, David L.; Surace, Jason A.; Intermediate Palomar Transient Factory Collaboration

    2016-01-01

    Beginning in 2013, the Intermediate Palomar Transient Factory has conducted a survey of the Northern Galactic Plane. The major science goals of the survey include mapping variable stars throughout the Galaxy; discovering outbursting sources such as Cataclysmic Variables, FU Ori outbursts, and M-dwarf flares; and identifying rare types of compact binaries. Through 2015 the survey has obtained an average of 60 epochs in R-band in the spatial region 0 < l < 150 degrees, |b| < 20 degrees, with greatest coverage in the |b| < 5 degree region.I will describe the performance of the survey and present initial results, with a focus on variability-based identification of X-ray sources. The Zwicky Transient Facility, to begin in 2017, will include an extensive public variability survey of the Galactic Plane.

  19. Deployment of a Curved Truss

    NASA Technical Reports Server (NTRS)

    Giersch, Louis R.; Knarr, Kevin

    2010-01-01

    Structures capable of deployment into complex, three-dimensional trusses have well known space technology applications such as the support of spacecraft payloads, communications antennas, radar reflectors, and solar concentrators. Such deployable trusses could also be useful in terrestrial applications such as the rapid establishment of structures in military and emergency service situations, in particular with regard to the deployment of enclosures for habitat or storage. To minimize the time required to deploy such an enclosure, a single arch-shaped truss is preferable to multiple straight trusses arranged vertically and horizontally. To further minimize the time required to deploy such an enclosure, a synchronous deployment with a single degree of freedom is also preferable. One method of synchronizing deployment of a truss is the use of a series of gears; this makes the deployment sequence predictable and testable, allows the truss to have a minimal stowage volume, and the deployed structure exhibits the excellent stiffness-to-mass and strength-to-mass ratios characteristic of a truss. A concept for using gears with varying ratios to deploy a truss into a curved shape has been developed and appears to be compatible with both space technology applications as well as potential use in terrestrial applications such as enclosure deployment. As is the case with other deployable trusses, this truss is formed using rigid elements (e.g., composite tubes) along the edges, one set of diagonal elements composed of either cables or folding/hinged rigid members, and the other set of diagonal elements formed by a continuous cable that is tightened by a motor or hand crank in order to deploy the truss. Gears of varying ratios are used to constrain the deployment to a single degree of freedom, making the deployment synchronous, predictable, and repeatable. The relative sizes of the gears and the relative dimensions of the diagonal elements determine the deployed geometry (e

  20. A rational biomimetic approach to structure defect generation in colloidal nanocrystals.

    PubMed

    Ruan, Lingyan; Ramezani-Dakhel, Hadi; Lee, Chain; Li, Yongjia; Duan, Xiangfeng; Heinz, Hendrik; Huang, Yu

    2014-07-22

    Controlling the morphology of nanocrystals (NCs) is of paramount importance for both fundamental studies and practical applications. The morphology of NCs is determined by the seed structure and the following facet growth. While means for directing facet formation in NC growth have been extensively studied, rational strategies for the production of NCs bearing structure defects in seeds have been much less explored. Here, we report mechanistic investigations of high density twin formation induced by specific peptides in platinum (Pt) NC growth, on the basis of which we derive principles that can serve as guidelines for the rational design of molecular surfactants to introduce high yield twinning in noble metal NC syntheses. Two synergistic factors are identified in producing twinned Pt NCs with the peptide: (1) the altered reduction kinetics and crystal growth pathway as a result of the complex formation between the histidine residue on the peptide and Pt ions, and (2) the preferential stabilization of {111} planes upon the formation of twinned seeds. We further apply the discovered principles to the design of small organic molecules bearing similar binding motifs as ligands/surfactants to create single and multiple twinned Pd and Rh NCs. Our studies demonstrate the rich information derived from biomimetic synthesis and the broad applicability of biomimetic principles to NC synthesis for diverse property tailoring.

  1. Cutting Plane Algorithms for Maximum Problems

    DTIC Science & Technology

    1991-12-01

    Bazaraa and Shetty (1979). For variational inequalities, references on the cutting plane approach are considerably less. Zuhovickii et al. (1969) (see...and can be expressed as a convex combination of a finite number of extreme points [see, e.g., Bazaraa et al., (1990)], For VI problems, both U and X are...unique solution (see, page 234 of Bazaraa and Shetty, 1979)., 32 Figure 4: A ’Strong’ Solution to a Variational Inequality Problem The rate of

  2. Linear instability of supersonic plane wakes

    NASA Technical Reports Server (NTRS)

    Papageorgiou, D. T.

    1989-01-01

    In this paper we present a theoretical and numerical study of the growth of linear disturbances in the high-Reynolds-number and laminar compressible wake behind a flat plate which is aligned with a uniform stream. No ad hoc assumptions are made as to the nature of the undisturbed flow (in contrast to previous investigations) but instead the theory is developed rationally by use of proper wake-profiles which satisfy the steady equations of motion. The initial growth of near wake perturbation is governed by the compressible Rayleigh equation which is studied analytically for long- and short-waves. These solutions emphasize the asymptotic structures involved and provide a rational basis for a nonlinear development. The evolution of arbitrary wavelength perturbations is addressed numerically and spatial stability solutions are presented that account for the relative importance of the different physical mechanisms present, such as three-dimensionality, increasing Mach numbers enough (subsonic) Mach numbers, there exists a region of absolute instability very close to the trailing-edge with the majority of the wake being convectively unstable. At higher Mach numbers (but still not large-hypersonic) the absolute instability region seems to disappear and the maximum available growth-rates decrease considerably. Three-dimensional perturbations provide the highest spatial growth-rates.

  3. Using the population-shift mechanism to rationally introduce "Hill-type" cooperativity into a normally non-cooperative receptor.

    PubMed

    Simon, Anna J; Vallée-Bélisle, Alexis; Ricci, Francesco; Watkins, Herschel M; Plaxco, Kevin W

    2014-09-01

    Allosteric cooperativity, which nature uses to improve the sensitivity with which biomolecular receptors respond to small changes in ligand concentration, could likewise be of use in improving the responsiveness of artificial biosystems. Thus motivated, we demonstrate here the rational design of cooperative molecular beacons, a widely employed DNA sensor, using a generalizable population-shift approach in which we engineer receptors that equilibrate between a low-affinity state and a high-affinity state exposing two binding sites. Doing so we achieve cooperativity within error of ideal behavior, greatly steepening the beacon's binding curve relative to that of the parent receptor. The ability to rationally engineer cooperativity should prove useful in applications such as biosensors, synthetic biology and "smart" biomaterials, in which improved responsiveness is of value.

  4. Analytical modeling of PWAS in-plane and out-of-plane electromechanical impedance spectroscopy (EMIS)

    NASA Astrophysics Data System (ADS)

    Kamas, Tuncay; Lin, Bin; Giurgiutiu, Victor

    2013-04-01

    This paper discusses theoretical analysis of electro-mechanical impedance spectroscopy (EMIS) of piezoelectric wafer active sensor (PWAS). Both free and constrained PWAS EMIS models are developed for in-plane (lengthwise) and outof plane (thickness wise) mode. The paper starts with the general piezoelectric constitutive equations that express the linear relation between stress, strain, electric field and electric displacement. This is followed by the PWAS EMIS models with two assumptions: 1) constant electric displacement in thickness direction (D3) for out-of-plane mode; 2) constant electric field in thickness direction (E3) for in-plane mode. The effects of these assumptions on the free PWAS in-plane and out-of-plane EMIS models are studied and compared. The effects of internal damping of PWAS are considered in the analytical EMIS models. The analytical EMIS models are verified by Coupled Field Finite Element Method (CF-FEM) simulations and by experimental measurements. The extent of the agreement between the analytical and experimental EMIS results is discussed. The paper ends with summary, conclusions, and suggestions for future work.

  5. In-plane and out-of-plane motions of the human tympanic membrane

    PubMed Central

    Khaleghi, Morteza; Cheng, Jeffrey Tao; Furlong, Cosme; Rosowski, John J.

    2016-01-01

    Computer-controlled digital holographic techniques are developed and used to measure shape and four-dimensional nano-scale displacements of the surface of the tympanic membrane (TM) in cadaveric human ears in response to tonal sounds. The combination of these measurements (shape and sound-induced motions) allows the calculation of the out-of-plane (perpendicular to the surface) and in-plane (tangential) motion components at over 1 000 000 points on the TM surface with a high-degree of accuracy and sensitivity. A general conclusion is that the in-plane motion components are 10–20 dB smaller than the out-of-plane motions. These conditions are most often compromised with higher-frequency sound stimuli where the overall displacements are smaller, or the spatial density of holographic fringes is higher, both of which increase the uncertainty of the measurements. The results are consistent with the TM acting as a Kirchhoff–Love's thin shell dominated by out-of-plane motion with little in-plane motion, at least with stimulus frequencies up to 8 kHz. PMID:26827009

  6. On the Road Map of Vogel's Plane

    NASA Astrophysics Data System (ADS)

    Mkrtchyan, Ruben L.

    2016-01-01

    We define "population" of Vogel's plane as points for which universal character of adjoint representation is regular in the finite plane of its argument. It is shown that they are given exactly by all solutions of seven Diophantine equations of third order on three variables. We find all their solutions: classical series of simple Lie algebras (including an "odd symplectic" one), {D_{2,1,λ}} superalgebra, the line of sl(2) algebras, and a number of isolated solutions, including exceptional simple Lie algebras. One of these Diophantine equations, namely {knm=4k+4n+2m+12,} contains all simple Lie algebras, except so{(2N+1).} Among isolated solutions are, besides exceptional simple Lie algebras, so called {e_{71/2}} algebra and also two other similar unidentified objects with positive dimensions. In addition, there are 47 isolated solutions in "unphysical semiplane" with negative dimensions. Isolated solutions mainly belong to the few lines in Vogel plane, including some rows of Freudenthal magic square. Universal dimension formulae have an integer values on all these solutions at least for first three symmetric powers of adjoint representation.

  7. Simulation Exploration through Immersive Parallel Planes: Preprint

    SciTech Connect

    Brunhart-Lupo, Nicholas; Bush, Brian W.; Gruchalla, Kenny; Smith, Steve

    2016-03-01

    We present a visualization-driven simulation system that tightly couples systems dynamics simulations with an immersive virtual environment to allow analysts to rapidly develop and test hypotheses in a high-dimensional parameter space. To accomplish this, we generalize the two-dimensional parallel-coordinates statistical graphic as an immersive 'parallel-planes' visualization for multivariate time series emitted by simulations running in parallel with the visualization. In contrast to traditional parallel coordinate's mapping the multivariate dimensions onto coordinate axes represented by a series of parallel lines, we map pairs of the multivariate dimensions onto a series of parallel rectangles. As in the case of parallel coordinates, each individual observation in the dataset is mapped to a polyline whose vertices coincide with its coordinate values. Regions of the rectangles can be 'brushed' to highlight and select observations of interest: a 'slider' control allows the user to filter the observations by their time coordinate. In an immersive virtual environment, users interact with the parallel planes using a joystick that can select regions on the planes, manipulate selection, and filter time. The brushing and selection actions are used to both explore existing data as well as to launch additional simulations corresponding to the visually selected portions of the input parameter space. As soon as the new simulations complete, their resulting observations are displayed in the virtual environment. This tight feedback loop between simulation and immersive analytics accelerates users' realization of insights about the simulation and its output.

  8. Focal plane scanner with reciprocating spatial window

    NASA Technical Reports Server (NTRS)

    Mao, Chengye (Inventor)

    2000-01-01

    A focal plane scanner having a front objective lens, a spatial window for selectively passing a portion of the image therethrough, and a CCD array for receiving the passed portion of the image. All embodiments have a common feature whereby the spatial window and CCD array are mounted for simultaneous relative reciprocating movement with respect to the front objective lens, and the spatial window is mounted within the focal plane of the front objective. In a first embodiment, the spatial window is a slit and the CCD array is one-dimensional, and successive rows of the image in the focal plane of the front objective lens are passed to the CCD array by an image relay lens interposed between the slit and the CCD array. In a second embodiment, the spatial window is a slit, the CCD array is two-dimensional, and a prism-grating-prism optical spectrometer is interposed between the slit and the CCD array so as to cause the scanned row to be split into a plurality of spectral separations onto the CCD array. In a third embodiment, the CCD array is two-dimensional and the spatial window is a rectangular linear variable filter (LVF) window, so as to cause the scanned rows impinging on the LVF to be bandpass filtered into spectral components onto the CCD array through an image relay lens interposed between the LVF and the CCD array.

  9. Restoring Aperture Profile At Sample Plane

    SciTech Connect

    Jackson, J L; Hackel, R P; Lungershausen, A W

    2003-08-03

    Off-line conditioning of full-size optics for the National Ignition Facility required a beam delivery system to allow conditioning lasers to rapidly raster scan samples while achieving several technical goals. The main purpose of the optical system designed was to reconstruct at the sample plane the flat beam profile found at the laser aperture with significant reductions in beam wander to improve scan times. Another design goal was the ability to vary the beam size at the sample to scan at different fluences while utilizing all of the laser power and minimizing processing time. An optical solution was developed using commercial off-the-shelf lenses. The system incorporates a six meter relay telescope and two sets of focusing optics. The spacing of the focusing optics is changed to allow the fluence on the sample to vary from 2 to 14 Joules per square centimeter in discrete steps. More importantly, these optics use the special properties of image relaying to image the aperture plane onto the sample to form a pupil relay with a beam profile corresponding almost exactly to the flat profile found at the aperture. A flat beam profile speeds scanning by providing a uniform intensity across a larger area on the sample. The relayed pupil plane is more stable with regards to jitter and beam wander. Image relaying also reduces other perturbations from diffraction, scatter, and focus conditions. Image relaying, laser conditioning, and the optical system designed to accomplish the stated goals are discussed.

  10. The fundamental plane correlations for globular clusters

    NASA Technical Reports Server (NTRS)

    Djorgovski, S.

    1995-01-01

    In the parameter space whose axes include a radius (core, or half-light), a surface brightness (central, or average within the half-light radius), and the central projected velocity dispersion, globular clusters lie on a two-dimensional surface (a plane, if the logarithmic quantities are used). This is analogous to the 'fundamental plane' of elliptical galaxies. The implied bivariate correlations are the best now known for globular clusters. The derived scaling laws for the core properties imply that cluster cores are fully virialized, homologous systems, with a constant (M/L) ratio. The corresponding scaling laws on the half-light scale are differrent, but are nearly identical to those derived from the 'fundamental plane' of ellipticals. This may be due to the range of cluster concentrations, which are correlated with other parameters. A similar explanation for elliptical galaxies may be viable. These correlations provide new empirical constraints for models of globular cluster formation and evolution, and may also be usable as rough distance-indicator relations for globular clusters.

  11. Blackfolds, plane waves and minimal surfaces

    NASA Astrophysics Data System (ADS)

    Armas, Jay; Blau, Matthias

    2015-07-01

    Minimal surfaces in Euclidean space provide examples of possible non-compact horizon geometries and topologies in asymptotically flat space-time. On the other hand, the existence of limiting surfaces in the space-time provides a simple mechanism for making these configurations compact. Limiting surfaces appear naturally in a given space-time by making minimal surfaces rotate but they are also inherent to plane wave or de Sitter space-times in which case minimal surfaces can be static and compact. We use the blackfold approach in order to scan for possible black hole horizon geometries and topologies in asymptotically flat, plane wave and de Sitter space-times. In the process we uncover several new configurations, such as black helicoids and catenoids, some of which have an asymptotically flat counterpart. In particular, we find that the ultraspinning regime of singly-spinning Myers-Perry black holes, described in terms of the simplest minimal surface (the plane), can be obtained as a limit of a black helicoid, suggesting that these two families of black holes are connected. We also show that minimal surfaces embedded in spheres rather than Euclidean space can be used to construct static compact horizons in asymptotically de Sitter space-times.

  12. Control of gradual plane change during aerocruise

    NASA Astrophysics Data System (ADS)

    Cochran, J. E., Jr.; Lee, S.; No, T. S.

    Motivated by the continuing interest in orbital maneuvering using aerodynamic forces and the oft overlooked close relationship between performance and stability analyses, we consider the stability and control of small plane change maneuvers during aerocruise. We use a model which consists of linear equations for perturbed motion with respect to a great circle trajectory about a non-rotating earth in terms of variables which allow uncoupling of the longitudinal and lateral dynamics, and partial uncoupling of lateral dynamics. Characteristics of the perturbed motion of a hypersonic flight vehicle with respect to a great circle trajectory are reviewed, including previous results which show that a change in the orientation of the great circle plane results from a general perturbation in initial conditions. This change is analogous to the heading change and lateral displacement which occur when a conventional aircraft's motion is disturbed. A linear quadratic controller for small plane change maneuvers is obtained, and an inverse method for generating controls for a steady-state aerocruise turn is described. An example is presented which shows that the majority of the optimal maneuver is approximated very well by the steady-state turn.

  13. Antenna arrays for producing plane whistler waves

    NASA Astrophysics Data System (ADS)

    Stenzel, Reiner; Urrutia, J. Manuel

    2014-10-01

    Linear whistler modes with ω ~= 0 . 3ωce <<ωpe are excited in a large laboratory plasma with magnetic loop antennas. A single antenna always produces a spatially bounded wave packet whose propagation cannot be directly compared to plane wave theories. By superimposing the fields from spatially separated antennas, the wavenumber along the antenna array can be nearly eliminated. 2D arrays nearly produce plane waves. The angle θ of wave propagation has been varied by a phase shift along the array. The refractive index surface n (θ) has been measured. The parallel phase and group velocities for Gendrin modes has been demonstrated. The interference between two oblique plane whistlers creates a whistler ``waveguide'' mode, i.e. standing waves for k ⊥B0 and propagation for k | |B0 . It also describes the reflection of oblique whistlers from a sharp discontinuity in the refractive index or conductivity. Radial reflections are also a dominant factor in small plasma columns of helicon devices. These results are of interest to space and laboratory plasmas. Work supported by NSF/DOE.

  14. Hamiltonian maps in the complex plane

    SciTech Connect

    Greene, J.M.; Percival, I.C.

    1981-01-01

    Following Arnol'd's proof of the KAM theorem, an analogy with the vertical pendulum, and some general arguments concerning maps in the complex plane, detailed calculations are presented and illustrated graphically for the standard map at the golden mean frequency. The functional dependence of the coordinate q on the canonical angle variable theta is analytically continued into the complex theta-plane, where natural boundaries are found at constant absolute values of Im theta. The boundaries represent the appearance of chaotic motion in the complex plane. Two independent numerical methods based on Fourier analysis in the angle variable were used, one based on a variation-annihilation method and the other on a double expansion. The results were further checked by direct solution of the complex equations of motion. The numerically simpler, but intrinsically complex, semipendulum and semistandard map are also studied. We conjecture that natural boundaries appear in the analogous analytic continuation of the invariant tori or KAM surfaces of general nonintegrable systems.

  15. Cleavage plane determination in amphibian eggs.

    PubMed

    Sawai, T; Yomota, A

    1990-01-01

    In the present study using eggs of Cynops pyrrhogaster and Xenopus laevis, we examined (1) structural changes in the cytoplasm before the appearance of the cleavage furrow using a cytochemical method, (2) the time of cleavage plane determination depending on the mitotic apparatus (MA), by changing the shape of the eggs, and (3) the time of arrival of the "cleavage stimulus" at the cortex, by injecting colchicine solution or removing cytoplasm. Results were as follows: (1) In amphibian eggs the diastema was formed after development of the MA, appearing between the two asters after the MA had begun to degenerate. (2) The cleavage plane was preliminarily determined by the MA in the meta- to anaphase of karyokinesis. At this time, however, the egg cortex had not yet received the "cleavage stimulus" indispensable for furrow formation. (3) The egg cortex was really prepared to establish the furrow just after the edge of the diastema arrived at the cortex, when the MA had already degenerated. These results imply that the cleavage plane of the amphibian eggs is determined in two steps: the first, depending on the MA, is the determination of the direction of the growth of the diastema, and the second is the arrival of the "cleavage stimulus" at the cortex in association with the diastema.

  16. Rational Emotive Behavior Therapy (REBT), Irrational and Rational Beliefs, and the Mental Health of Athletes

    PubMed Central

    Turner, Martin J.

    2016-01-01

    In this article Rational Emotive Behavior Therapy (REBT) is proposed as a potentially important framework for the understanding and promotion of mental health in athletes. Cognitive-behavioral approaches predominate in the provision of sport psychology, and often form the backbone of psychological skills training for performance enhancement and maintenance. But far from being solely performance-focused, the cognitive-behavioral approach to sport psychology can restore, promote, and maintain mental health. This review article presents REBT (Ellis, 1957), the original cognitive behavioral therapy, as a valuable approach to addressing mental health issues in sport. REBT holds that it is not events that directly cause emotions and behaviors. Rather, it is one’s beliefs about the events that lead to emotional and behavioral reactivity. Further, REBT distinguishes between rational and irrational beliefs, and suggests that in response to failure, maltreatment, and misfortune, people can react with either healthy or unhealthy emotional and behavioral responses. The extant research indicates that irrational beliefs lead to unhealthy negative emotions, a range of pathological conditions, and a host of maladaptive behaviors that undermine mental health. Therefore, REBT proposes a process for the reduction of irrational beliefs and the promotion of rational beliefs. The use of REBT in sport is seldom reported in literature, but research is growing. This review article proposes three important areas of investigation that will aid the understanding of irrational beliefs and the application of REBT within sport. These areas are: (1) the influence of irrational beliefs and REBT on the mental health of athletes, (2) the influence of irrational beliefs and REBT on athletic performance, (3) the origins and development of irrational beliefs in athletes. Each area is discussed in turn, offering a critical and progressive review of the literature as well as highlighting research

  17. Rational Emotive Behavior Therapy (REBT), Irrational and Rational Beliefs, and the Mental Health of Athletes.

    PubMed

    Turner, Martin J

    2016-01-01

    In this article Rational Emotive Behavior Therapy (REBT) is proposed as a potentially important framework for the understanding and promotion of mental health in athletes. Cognitive-behavioral approaches predominate in the provision of sport psychology, and often form the backbone of psychological skills training for performance enhancement and maintenance. But far from being solely performance-focused, the cognitive-behavioral approach to sport psychology can restore, promote, and maintain mental health. This review article presents REBT (Ellis, 1957), the original cognitive behavioral therapy, as a valuable approach to addressing mental health issues in sport. REBT holds that it is not events that directly cause emotions and behaviors. Rather, it is one's beliefs about the events that lead to emotional and behavioral reactivity. Further, REBT distinguishes between rational and irrational beliefs, and suggests that in response to failure, maltreatment, and misfortune, people can react with either healthy or unhealthy emotional and behavioral responses. The extant research indicates that irrational beliefs lead to unhealthy negative emotions, a range of pathological conditions, and a host of maladaptive behaviors that undermine mental health. Therefore, REBT proposes a process for the reduction of irrational beliefs and the promotion of rational beliefs. The use of REBT in sport is seldom reported in literature, but research is growing. This review article proposes three important areas of investigation that will aid the understanding of irrational beliefs and the application of REBT within sport. These areas are: (1) the influence of irrational beliefs and REBT on the mental health of athletes, (2) the influence of irrational beliefs and REBT on athletic performance, (3) the origins and development of irrational beliefs in athletes. Each area is discussed in turn, offering a critical and progressive review of the literature as well as highlighting research

  18. Dissociative Recombination without a Curve Crossing

    NASA Technical Reports Server (NTRS)

    Guberman, Steven L.

    1994-01-01

    Ab initio calculations show that a curve crossing is not always needed for a high dissociative- recombination cross section. For HeH(+), in which no neutral states cross the ion potential curve, dissociative recombination is driven by the nuclear kinetic-energy operator on adiabatic potential curves. The kinetic-energy derivative operator allows for capture into repulsive curves that are outside of the classical turning points for the nuclear motion. The dominant dissociative route is the C (2)Sigma(+) state leading to H(n = 2) atoms. An analogous mechanism is proposed for the dissociative recombination of H3(+).

  19. A kill curve for Phanerozoic marine species

    NASA Technical Reports Server (NTRS)

    Raup, D. M.

    1991-01-01

    A kill curve for Phanerozoic species is developed from an analysis of the stratigraphic ranges of 17,621 genera, as compiled by Sepkoski. The kill curve shows that a typical species' risk of extinction varies greatly, with most time intervals being characterized by very low risk. The mean extinction rate of 0.25/m.y. is thus a mixture of long periods of negligible extinction and occasional pulses of much higher rate. Because the kill curve is merely a description of the fossil record, it does not speak directly to the causes of extinction. The kill curve may be useful, however, to li inverted question markmit choices of extinction mechanisms.

  20. A theoretical and experimental investigation of the effects of yaw on pressures, forces, and moments during seaplane landings and planing

    NASA Technical Reports Server (NTRS)

    Smiley, Robert F

    1952-01-01

    A theory for the side force, rolling moment, yawing moment, and pressure distribution during yawed landings and planing of seaplanes was developed. For the special case of the straight-sided wedge without chine immersion, the results of the theoretical analysis are presented in the form of generalized curves covering all step landing conditions. Experimental impact and planing data are presented for a prismatic wedge having an angle of dead rise of 22.5 degrees and are shown to be in reasonable agreement with the theoretical predictions.

  1. The plain truth about forming a plane wave of neutrons

    NASA Astrophysics Data System (ADS)

    Wagh, Apoorva G.; Abbas, Sohrab; Treimer, Wolfgang

    2011-04-01

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

  2. Monte Carlo calculations of correction factors for plane-parallel ionization chambers in clinical electron dosimetry

    SciTech Connect

    Araki, Fujio

    2008-09-15

    Recent standard dosimetry protocols recommend that plane-parallel ionization chambers be used in the measurements of depth-dose distributions or the calibration of low-energy electron beams with beam quality R{sub 50}<4 g/cm{sup 2}. In electron dosimetry protocols with the plane-parallel chambers, the wall correction factor, P{sub wall}, in water is assumed to be unity and the replacement correction factor, P{sub repl}, is taken to be unity for well-guarded plane-parallel chambers, at all measurement depths. This study calculated P{sub wall} and P{sub repl} for NACP-02, Markus, and Roos plane-parallel chambers in clinical electron dosimetry using the EGSnrc Monte Carlo code system. The P{sub wall} values for the plane-parallel chambers increased rapidly as a function of depth in water, especially at lower energy. The value around R{sub 50} for NACP-02 was about 10% greater than unity at 4 MeV. The effect was smaller for higher electron energies. Similarly, P{sub repl} values with depth increased drastically at the region with the steep dose gradient for lower energy. For Markus P{sub repl} departed more than 10% from unity close to R{sub 50} due to the narrow guard ring width. P{sub repl} for NACP-02 and Roos was close to unity in the plateau region of depth-dose curves that includes a reference depth, d{sub ref}. It was also found that the ratio of the dose to water and the dose to the sensitive volume in the air cavity for the plane-parallel chambers, D{sub w}/[D{sub air}]{sub pp}, at d{sub ref} differs significantly from that assumed by electron dosimetry protocols.

  3. Sunitinib: from rational design to clinical efficacy.

    PubMed

    Chow, Laura Q M; Eckhardt, S Gail

    2007-03-01

    Sunitinib (SU011248) is an oral small molecular tyrosine kinase inhibitor that exhibits potent antiangiogenic and antitumor activity. Tyrosine kinase inhibitors such as SU6668 and SU5416 (semaxanib) demonstrated poor pharmacologic properties and limited efficacy; therefore, sunitinib was rationally designed and chosen for its high bioavailability and its nanomolar-range potency against the antiangiogenic receptor tyrosine kinases (RTKs)--vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR). Sunitinib inhibits other tyrosine kinases including, KIT, FLT3, colony-stimulating factor 1 (CSF-1), and RET, which are involved in a number of malignancies including small-cell lung cancer, GI stromal tumors (GISTs), breast cancer, acute myelogenous leukemia, multiple endocrine neoplasia types 2A and 2B, and familial medullary thyroid carcinoma. Sunitinib demonstrated robust antitumor activity in preclinical studies resulting not only in tumor growth inhibition, but tumor regression in models of colon cancer, non-small-cell lung cancer, melanoma, renal carcinoma, and squamous cell carcinoma, which were associated with inhibition of VEGFR and PDGFR phosphorylation. Clinical activity was demonstrated in neuroendocrine, colon, and breast cancers in phase II studies, whereas definitive efficacy has been demonstrated in advanced renal cell carcinoma and in imatinib-refractory GISTs, leading to US Food and Drug Administration approval of sunitinib for treatment of these two diseases. Studies investigating sunitinib alone in various tumor types and in combination with chemotherapy are ongoing. The clinical benchmarking of this small-molecule inhibitor of members of the split-kinase domain family of RTKs will lead to additional insights regarding the biology, potential biomarkers, and clinical utility of agents that target multiple signaling pathways in tumor, stromal, and endothelial compartments.

  4. Biomimetic transport and rational drug delivery.

    PubMed

    Ranney, D F

    2000-01-15

    Medicine and pharmaceutics are encountering critical needs and opportunities for transvascular drug delivery that improves site targeting and tissue permeation by mimicking natural tissue addressing and transport mechanisms. This is driven by the accelerated development of genomic agents requiring targeted controlled release. Although rationally designed for in vitro activity, such agents are not highly effective in vivo, due to opsonization and degradation by plasma constituents, and failure to transport across the local vascular endothelium and tissue matrix. A growing knowledge of the addresses of the body can be applied to engineer "Bio-Logically" staged delivery systems with sequential bioaddressins complementary to the discontinuous compartments encountered--termed discontinuum pharmaceutics. Effective tissue targeting is accomplished by leukocytes, bacteria, and viruses. We are increasingly able to mimic their bioaddressins by genomic means. Approaches described in this commentary include: (a) endothelial-directed adhesion mediated by oligosaccharides and carbohydrates (e.g. dermatan sulfate as a mimic of sulfated CD44) and peptidomimetics interacting with adhesins, selectins, integrins, hyaluronans, and locally induced growth factors (e.g. vascular endothelial growth factor, VEGF) and coagulation factors (e.g. factor VIII antigen); (b) improved tissue permeation conferred by hydrophilically "cloaked" carrier systems; (c) "uncloaking" by matrix dilution or selective triggering near the target cells; and (d) target binding-internalization by terminally exposed hydrophobic moieties, cationic polymers, and receptor-binding lectins, peptides, or carbohydrates. This commentary also describes intermediate technology solutions (e.g. "hybrid drugs"), and highlights the high-resolution, dynamic magnetic resonance imaging and radiopharmaceutical imaging technologies plus the groups and organizations capable of accelerating these important initiatives.

  5. A psychoanalytic model for human freedom and rationality.

    PubMed

    Macklin, R

    1976-07-01

    The nature and scope of freedom and rationality in man are explored in light of the problems posed by a deterministic framework for understanding and explaining human though, feeling, and behavior. It is argued that the sort of explanation afforded by a psychodynamic theory is fully compatible with attributing freedom and rationality to persons. In particular, psychoanalytic theory is able to account for the existence of causal laws governing all aspects of human behavior, while providing a schema by which we can distinguish rational from irrational behavior, and free acts from those that are unfree.

  6. Numerical analysis of curved frequency selective surface by finite-difference time-domain

    NASA Astrophysics Data System (ADS)

    Chen, Xin-yi; Wang, Jian-bo; Chen, Gui-bo; Sun, Guan-cheng; Lu, Jun

    2011-08-01

    Frequency selective surface is a monolayer or multilayer 2D periodic structure which is composed of multiple resonance units scattering by a two-dimensional periodic array on dielectric layer. FSS can't absorb radio frequency energy, but can filter the frequency which is therefore applied in microwave technique or stealth technology. The relative research on curved FSS is relatively scarce since the curved FSS structure can be obtained only when FSS is attached on the materials surfaces of curved structures in engineering application. However, curved FSS is widely applied in practical engineering; therefore, the research on curved FSS structure has important significance. In this paper, a curved FSS structure model of Y-pore unit is established and numerical simulated by means of FDTD. The influence of curvature on FSS transmission characteristics is studied according to the analysis on the changing of radar cross section (RCS). The results show: the center frequency point of the plane band pass FSS structure drifts after the curve surface deformation of the structure; the center frequency point of the curved band pass FSS structure drifts with the changing of the curvature radius, i. e. with the decreasing of curvature radius, the frequency point drifts towards high points and the transmittance decreases. The design of FSS radome demands of accurate and stable center resonance frequency; therefore, the actual situation of curved surface should be considered in practical engineering application when band pass FSS is made into frequency selection filtering radome. The curvature radius should be long enough to avoid center frequency drifting and transmittance deceasing.

  7. Fractional Fourier transforms, symmetrical lens systems, and their cardinal planes.

    PubMed

    Moreno, Ignacio; Sánchez-López, María M; Ferreira, Carlos; Mateos, Felipe

    2007-07-01

    We study the relation between optical lens systems that perform a fractional Fourier transform (FRFT) with the geometrical cardinal planes. We demonstrate that lens systems symmetrical with respect to the central plane provide an exact FRFT link between the input and output planes. Moreover, we show that the fractional order of the transform has real values between 0 and 2 when light propagation is produced between principal planes and antiprincipal planes, respectively. Finally, we use this new point of view to design an optical lens system that provides FRFTs with variable fractional order in the range (0,2) without moving the input and output planes.

  8. X-ray characterization of curved crystals for hard x-ray astronomy

    NASA Astrophysics Data System (ADS)

    Buffagni, Elisa; Bonnini, Elisa; Ferrari, Claudio; Virgilli, Enrico; Frontera, Filippo

    2015-05-01

    Among the methods to focus photons the diffraction in crystals results as one of the most effective for high energy photons. An assembling of properly oriented crystals can form a lens able to focus x-rays at high energy via Laue diffraction in transmission geometry; this is a Laue lens. The x-ray diffraction theory provides that the maximum diffraction efficiency is achieved in ideal mosaic crystals, but real mosaic crystals show diffraction efficiencies several times lower than the ideal case due to technological problems. An alternative and convenient approach is the use of curved crystals. We have recently optimized an efficient method based on the surface damage of crystals to produce self-standing uniformly curved Si, GaAs and Ge tiles of thickness up to 2-3 mm and curvature radii R down to a few meters. We show that, for curved diffracting planes, such crystals have a diffraction efficiency nearly forty times higher than the diffraction efficiency of perfect similar flat crystals, thus very close to that of ideal mosaic crystals. Moreover, in an alternative configuration where the diffracting planes are perpendicular to the curved ones, a focusing effect occurs and will be shown. These results were obtained for several energies between 17 and 120 keV with lab sources or at high energy facilities such as LARIX at Ferrara (Italy), ESRF at Grenoble (France), and ANKA at Karlsruhe (Germany).

  9. Forces in the complex octonion curved space

    NASA Astrophysics Data System (ADS)

    Weng, Zi-Hua

    2016-04-01

    The paper aims to extend major equations in the electromagnetic and gravitational theories from the flat space into the complex octonion curved space. Maxwell applied simultaneously the quaternion analysis and vector terminology to describe the electromagnetic theory. It inspires subsequent scholars to study the electromagnetic and gravitational theories with the complex quaternions/octonions. Furthermore Einstein was the first to depict the gravitational theory by means of tensor analysis and curved four-space-time. Nowadays some scholars investigate the electromagnetic and gravitational properties making use of the complex quaternion/octonion curved space. From the orthogonality of two complex quaternions, it is possible to define the covariant derivative of the complex quaternion curved space, describing the gravitational properties in the complex quaternion curved space. Further it is possible to define the covariant derivative of the complex octonion curved space by means of the orthogonality of two complex octonions, depicting simultaneously the electromagnetic and gravitational properties in the complex octonion curved space. The result reveals that the connection coefficient and curvature of the complex octonion curved space will exert an influence on the field strength and field source of the electromagnetic and gravitational fields, impacting the linear momentum, angular momentum, torque, energy, and force and so forth.

  10. Electrical-Discharge Machining Of Curved Passages

    NASA Technical Reports Server (NTRS)

    Guirguis, Kamal S.

    1993-01-01

    Electrical-discharge machining (EDM) used to cut deep hole with bends. EDM process done with articulating segmented electrode. Originally straight, electrode curved as it penetrates part, forming long, smoothly curving hole. After hole cut, honed with slurry to remove thin layer of recast metal created by EDM. Breakage of tools, hand deburring, and drilling debris eliminated.

  11. Mixture Modeling of Individual Learning Curves

    ERIC Educational Resources Information Center

    Streeter, Matthew

    2015-01-01

    We show that student learning can be accurately modeled using a mixture of learning curves, each of which specifies error probability as a function of time. This approach generalizes Knowledge Tracing [7], which can be viewed as a mixture model in which the learning curves are step functions. We show that this generality yields order-of-magnitude…

  12. Cost Curves and How They Relate.

    ERIC Educational Resources Information Center

    Mixon, J. Wilson; Tohemy, Soumaya M.

    2002-01-01

    Describes a Web site that contains Microsoft Excel workbooks that draft consistent short-run and long-run cost curves and the text describing them. Details a common error in representing the curves. Reports that the Web site also presents revenues and profits for a price taker and a price maker. (JEH)

  13. Forgetting Curves: Implications for Connectionist Models

    ERIC Educational Resources Information Center

    Sikstrom, Sverker

    2002-01-01

    Forgetting in long-term memory, as measured in a recall or a recognition test, is faster for items encoded more recently than for items encoded earlier. Data on forgetting curves fit a power function well. In contrast, many connectionist models predict either exponential decay or completely flat forgetting curves. This paper suggests a…

  14. Parallel Curves: Getting There and Getting Back

    ERIC Educational Resources Information Center

    Agnew, A. F.; Mathews, J. H.

    2006-01-01

    This note takes up the issue of parallel curves while illustrating the utility of "Mathematica" in computations. This work complements results presented earlier. The presented treatment, considering the more general case of parametric curves, provides an analysis of the appearance of cusp singularities, and emphasizes the utility of symbolic…

  15. Measuring Model Rocket Engine Thrust Curves

    ERIC Educational Resources Information Center

    Penn, Kim; Slaton, William V.

    2010-01-01

    This paper describes a method and setup to quickly and easily measure a model rocket engine's thrust curve using a computer data logger and force probe. Horst describes using Vernier's LabPro and force probe to measure the rocket engine's thrust curve; however, the method of attaching the rocket to the force probe is not discussed. We show how a…

  16. Flow measurements in a model of the mildly curved femoral artery of man

    NASA Technical Reports Server (NTRS)

    Back, L. H.; Kwack, E. Y.; Crawford, D. W.

    1990-01-01

    The effects of curvature on the flow rate near the wall in the vicinity of the mildly curved femoral artery of man, and on the pressure distributions along the curved segment, were investigated using glass and tygon flow models constructed to conform to the shape of the femoral angiogram of a human subject. The test fluid was 33 percent aqueous sucrose. Steady flow observations, made using a dye flow visualization system, revealed a flow pattern like that observed in coiled pipes. A double helical type flow was found to develop, with converging streamlines in the wall vicinity from the upper and lower plane of curvature merging asymptotically along the inner curvature in a stable manner. Pressure measurements for steady flow revealed progressively larger pressure drops with distance along the entrance region of the curved segment, relative to that for a straight lumen.

  17. An efficient method to compute microlensed light curves for point sources

    NASA Technical Reports Server (NTRS)

    Witt, Hans J.

    1993-01-01

    We present a method to compute microlensed light curves for point sources. This method has the general advantage that all microimages contributing to the light curve are found. While a source moves along a straight line, all micro images are located either on the primary image track or on the secondary image tracks (loops). The primary image track extends from - infinity to + infinity and is made of many sequents which are continuously connected. All the secondary image tracks (loops) begin and end on the lensing point masses. The method can be applied to any microlensing situation with point masses in the deflector plane, even for the overcritical case and surface densities close to the critical. Furthermore, we present general rules to evaluate the light curve for a straight track arbitrary placed in the caustic network of a sample of many point masses.

  18. Fick-Jacobs equation for channels over three-dimensional curves

    NASA Astrophysics Data System (ADS)

    Valero Valdes, Carlos; Herrera Guzman, Rafael

    2014-11-01

    The purpose of this paper is to provide a new formula for the effective diffusion coefficient of a generalized Fick-Jacobs equation for narrow three-dimensional channels. The generalized Fick-Jacobs equation is obtained by projecting the three-dimensional diffusion equation along the normal directions of a curve in three-dimensional space that roughly resembles the narrow channel. The projection (or dimensional reduction) is achieved by integrating the diffusion equation along the cross sections of the channel contained in the planes orthogonal to the curve. We show that the resulting formula for the associated effective diffusion coefficient can be expressed in terms of the geometric moments of the channel's cross sections and the curve's curvature. We show the effect that a rotating cross section with offset has on the effective diffusion coefficient.

  19. Remote sensing used for power curves

    NASA Astrophysics Data System (ADS)

    Wagner, R.; Jørgensen, H. E.; Paulsen, U. S.; Larsen, T. J.; Antoniou, I.; Thesbjerg, L.

    2008-05-01

    : Power curve measurement for large wind turbines requires taking into account more parameters than only the wind speed at hub height. Based on results from aerodynamic simulations, an equivalent wind speed taking the wind shear into account was defined and found to reduce the power standard deviation in the power curve significantly. Two LiDARs and a SoDAR are used to measure the wind profile in front of a wind turbine. These profiles are used to calculate the equivalent wind speed. The comparison of the power curves obtained with the three instruments to the traditional power curve, obtained using a cup anemometer measurement, confirms the results obtained from the simulations. Using LiDAR profiles reduces the error in power curve measurement, when these are used as relative instrument together with a cup anemometer. Results from the SoDAR do not show such promising results, probably because of noisy measurements resulting in distorted profiles.

  20. Curved and conformal high-pressure vessel

    SciTech Connect

    Croteau, Paul F.; Kuczek, Andrzej E.; Zhao, Wenping

    2016-10-25

    A high-pressure vessel is provided. The high-pressure vessel may comprise a first chamber defined at least partially by a first wall, and a second chamber defined at least partially by the first wall. The first chamber and the second chamber may form a curved contour of the high-pressure vessel. A modular tank assembly is also provided, and may comprise a first mid tube having a convex geometry. The first mid tube may be defined by a first inner wall, a curved wall extending from the first inner wall, and a second inner wall extending from the curved wall. The first inner wall may be disposed at an angle relative to the second inner wall. The first mid tube may further be defined by a short curved wall opposite the curved wall and extending from the second inner wall to the first inner wall.

  1. Rational solitons of wave resonant-interaction models

    NASA Astrophysics Data System (ADS)

    Degasperis, Antonio; Lombardo, Sara

    2013-11-01

    Integrable models of resonant interaction of two or more waves in 1+1 dimensions are known to be of applicative interest in several areas. Here we consider a system of three coupled wave equations which includes as special cases the vector nonlinear Schrödinger equations and the equations describing the resonant interaction of three waves. The Darboux-Dressing construction of soliton solutions is applied under the condition that the solutions have rational, or mixed rational-exponential, dependence on coordinates. Our algebraic construction relies on the use of nilpotent matrices and their Jordan form. We systematically search for all bounded rational (mixed rational-exponential) solutions and find a broad family of such solutions of the three wave resonant interaction equations.

  2. Finding Bounded Rational Equilibria. Part 1; Iterative Focusing

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.

    2004-01-01

    A long-running difficulty with conventional game theory has been how to modify it to accommodate the bounded rationality characterizing all real-world players. A recurring issue in statistical physics is how best to approximate joint probability distributions with decoupled (and therefore far more tractable) distributions. It has recently been shown that the same information theoretic mathematical structure, known as Probability Collectives (PC) underlies both issues. This relationship between statistical physics and game theory allows techniques and insights from the one field to be applied to the other. In particular, PC provides a formal model-independent definition of the degree of rationality of a player and of bounded rationality equilibria. This pair of papers extends previous work on PC by introducing new computational approaches to effectively find bounded rationality equilibria of common-interest (team) games.

  3. Cubic Polynomials with Rational Roots and Critical Points

    ERIC Educational Resources Information Center

    Gupta, Shiv K.; Szymanski, Waclaw

    2010-01-01

    If you want your students to graph a cubic polynomial, it is best to give them one with rational roots and critical points. In this paper, we describe completely all such cubics and explain how to generate them.

  4. Stress analysis in curved composites due to thermal loading

    NASA Astrophysics Data System (ADS)

    Polk, Jared Cornelius

    of such a problem. It was ascertained and proven that the general, non-modified (original) version of classical lamination theory cannot be used for an analytical solution for a simply curved beam or any other structure that would require rotations of laminates out their planes in space. Finite element analysis was used to ascertain stress variations in a simply curved beam. It was verified that these solutions reduce to the flat beam solutions as the radius of curvature of the beams tends to infinity. MATLAB was used to conduct the classical lamination theory numerical analysis. A MATLAB program was written to conduct the finite element analysis for the flat and curved beams, isotropic and composite. It does not require incompatibility techniques used in mechanics of isotropic materials for indeterminate structures that are equivalent to fixed-beam problems. Finally, it has the ability to enable the user to define and create unique elements not accessible in commercial software, and modify finite element procedures to take advantage of new paradigms.

  5. Wafer plane inspection with soft resist thresholding

    NASA Astrophysics Data System (ADS)

    Hess, Carl; Shi, Rui-fang; Wihl, Mark; Xiong, Yalin; Pang, Song

    2008-10-01

    Wafer Plane Inspection (WPI) is an inspection mode on the KLA-Tencor TeraScaTM platform that uses the high signalto- noise ratio images from the high numerical aperture microscope, and then models the entire lithographic process to enable defect detection on the wafer plane[1]. This technology meets the needs of some advanced mask manufacturers to identify the lithographically-significant defects while ignoring the other non-lithographically-significant defects. WPI accomplishes this goal by performing defect detection based on a modeled image of how the mask features would actually print in the photoresist. There are several advantages to this approach: (1) the high fidelity of the images provide a sensitivity advantage over competing approaches; (2) the ability to perform defect detection on the wafer plane allows one to only see those defects that have a printing impact on the wafer; (3) the use of modeling on the lithographic portion of the flow enables unprecedented flexibility to support arbitrary illumination profiles, process-window inspection in unit time, and combination modes to find both printing and non-printing defects. WPI is proving to be a valuable addition to the KLA-Tencor detection algorithm suite. The modeling portion of WPI uses a single resist threshold as the final step in the processing. This has been shown to be adequate on several advanced customer layers, but is not ideal for all layers. Actual resist chemistry has complicated processes including acid and base-diffusion and quench that are not consistently well-modeled with a single resist threshold. We have considered the use of an advanced resist model for WPI, but rejected it because the burdensome requirements for the calibration of the model were not practical for reticle inspection. This paper describes an alternative approach that allows for a "soft" resist threshold to be applied that provides a more robust solution for the most challenging processes. This approach is just

  6. Symmetrically converging plane thermonuclear burn waves

    NASA Astrophysics Data System (ADS)

    Charakhch'yan, A. A.; Khishchenko, K. V.

    2013-10-01

    Five variants of a one-dimensional problem on synchronous bilateral action of two identical drivers on opposite surfaces of a plane layer of DT fuel with the normal or five times greater initial density, where the solution includes two thermonuclear burn waves propagating to meet one another at the symmetry plane, are simulated. A laser pulse with total absorption of energy at the critical density (in two variants) and a proton bunch that provides for a nearly isochoric heating (in three variants) are considered as drivers. A wide-range equation of state for the fuel, electron and ion heat conduction, self-radiation of plasma and plasma heating by α-particles are taken into account. In spite of different ways of ignition, various models of α-particle heat, whether the burn wave remains slow or transforms into the detonation wave, and regardless of way of such a transformation, the final value of the burn-up factor depends essentially on the only parameter Hρ0, where H is the half-thickness of the layer and ρ0 is the initial fuel density. This factor is about 0.35 at Hρ0 ≈ 1 g cm-2 and about 0.7 at Hρ0 ≈ 5 g cm-2. The expansion stage of the flow (after reflecting the burn or detonation wave from the symmetry plane) gives the main contribution in forming the final values of the burn-up factor and the gain at Hρ0 ≈ 1 g cm-2 and increases them approximately two times at Hρ0 ≈ 5 g cm-2. In the case of the proton driver, the final value of the gain is about 200 at Hρ0 ≈ 1 g cm-2 and about 2000 at Hρ0 ≈ 5 g cm-2. In the case of the laser driver, the above values are four times less in conformity with the difference between the driver energies.

  7. Characterization of DECam focal plane detectors

    SciTech Connect

    Diehl, H.Thomas; Angstadt, Robert; Campa, Julia; Cease, Herman; Derylo, Greg; Emes, John H.; Estrada, Juan; Kibik, Donna; Flaugher, Brenna L.; Holland, Steve E.; Jonas, Michelle; /Fermilab /Madrid, CIEMAT /LBL, Berkeley /Argonne /Pennsylvania U.

    2008-06-01

    DECam is a 520 Mpix, 3 square-deg FOV imager being built for the Blanco 4m Telescope at CTIO. This facility instrument will be used for the 'Dark Energy Survey' of the southern galactic cap. DECam has chosen 250 ?m thick CCDs, developed at LBNL, with good QE in the near IR for the focal plane. In this work we present the characterization of these detectors done by the DES team, and compare it to the DECam technical requirements. The results demonstrate that the detectors satisfy the needs for instrument.

  8. Experiments with unilateral bite planes in rabbits.

    PubMed

    Sergl, H G; Farmland, M

    1975-04-01

    1. Insertion of bite planes on the right mandibular lateral teeth of eight young rabbits caused load changes in the masticatory system. Eight other animals served as controls. 2. The induced changes were equilibrated during the nine-week experimental period by adapation processes. At the end of the period all teeth were in occlusion and the glenoid fossa-condylar process distance was equal on both sides. 3. The adaptation was the result of several mechanisms working together. We found changes in the alveolar region and at distant growth structures. Cranial scolioses were observed. 4. Masticatory functional loading is a factor which regulates growth in the region of the facial skeleton.

  9. Coincidence lattices in the hyperbolic plane.

    PubMed

    Rodríguez-Andrade, M A; Aragón-González, G; Aragón, J L; Gómez-Rodríguez, A

    2011-01-01

    The problem of coincidences of lattices in the space R(p,q), with p + q = 2, is analyzed using Clifford algebra. We show that, as in R(n), any coincidence isometry can be decomposed as a product of at most two reflections by vectors of the lattice. Bases and coincidence indices are constructed explicitly for several interesting lattices. Our procedure is metric-independent and, in particular, the hyperbolic plane is obtained when p = q = 1. Additionally, we provide a proof of the Cartan-Dieudonné theorem for R(p,q), with p + q = 2, that includes an algorithm to decompose an orthogonal transformation into a product of reflections.

  10. Dynamic Shear Band Development in Plane Strain,

    DTIC Science & Technology

    1987-11-01

    dicular to the initial propagation direction slows (town and further straining occurs inl a hand. The ul1timlate course of events is essentially...pr scribed velocita oal ysiave e n/sec. lie order of ilacint fiie V1 = -3 I/seecorrspon i toean avera elcirt of -300/etersos(i setal *" increase inl ...Spitzig, WV.A., 1980, *Initiation of Localized Shear Bands inl Plane Siraiii..1. .1lcch. Phys. Solids. \\Vol. 28, pp. 113-128. Asaro. R.J., 1983

  11. Black Plane Solutions and Localized Gravitational Energy

    PubMed Central

    Roberts, Jennifer

    2015-01-01

    We explore the issue of gravitational energy localization for static plane-symmetric solutions of the Einstein-Maxwell equations in 3+1 dimensions with asymptotic anti-de Sitter behavior. We apply three different energy-momentum complexes, the Einstein, Landau-Lifshitz, and Møller prescriptions, to the metric representing this category of solutions and determine the energy distribution for each. We find that the three prescriptions offer identical energy distributions, suggesting their utility for this type of model. PMID:27347499

  12. The Simbol-X Focal Plane

    NASA Astrophysics Data System (ADS)

    Laurent, P.

    2009-05-01

    The Simbol-X focal plane is designed to detect photons focused by the mirror in the 0.5 to 100 keV energy band. Composed of two detectors, it will measure the position, energy, and arrival time of each incoming X-ray. On top of it will be a collimator to shield all photons not coming from the mirror field of view. The whole system is surrounded by an active and passive shielding in order to ensure the required very low background.

  13. Femoral bowing plane adaptation to femoral anteversion

    PubMed Central

    Akman, Alp; Demirkan, Fahir; Sabir, Nuran; Oto, Murat; Yorukoglu, Cagdas; Kiter, Esat

    2017-01-01

    Background: Femoral bowing plane (FBP) is the unattended subject in the literature. More over the femoral shaft with its bowing is neglected in established anteversion determination methods. There is limited information about the relationship between FBP and anteversion. Thus we focused on this subject and hypothesized that there could be an adaptation of FBP to anteversion. Materials and Methods: FBP is determined on three-dimensional solid models derived from the left femoral computerized tomography data of 47 patients which were taken before for another reason and comparatively evaluated with anteversion. There were 20 women and 27 men. The mean age of patients was 56 years (range 21–84 years). Results: The anteversion values were found as the angle between a distal condylar axis (DCA) and femoral neck anteversion axis (FNAA) along an imaginary longitudinal femoral axis (LFA) in the true cranio-caudal view. The FBP was determined as a plane that passes through the centre-points of three pre-determinated sections on the femoral shaft. The angles between DCA, FNAA and FBP were comparatively evaluated. The independent samples t-test was used for statistical analysis. At the end, it was found that FBP lies nearly perpendicular to the anteversion axis for the mean of our sample which is around 89° in females and 93° in males (range 78–102°). On the other hand, FBP does not lie close to the sagittal femoral plane (SFP); instead, there is an average 12.5° external rotation relative to the SFP. FBP is correlated well with anteversion in terms of FBP inclination from SFP and femoral torsion (i.e., angle between FBP and femoral neck anteversion axis (P < 0.001; r = 0.680 and r = −0.682, respectively). Combined correlation is perfect (R2 = 1) as the FBP, SFP, and posterior femoral plane forms a triangle in the cranio-caudal view. Conclusions: We found that FBP adapts to anteversion. As FBP lies close to perpendicularity for the mean, femoral component positioning

  14. Plane Strain Deformation in Generalized Thermoelastic Diffusion

    NASA Astrophysics Data System (ADS)

    Sharma, Nidhi; Kumar, Rajneesh; Ram, Paras

    2008-08-01

    The present investigation is concerned with plane strain deformation in homogeneous isotropic generalized thermoelastic diffusion subjected to a normal force, thermal source, and chemical potential source. Laplace and Fourier transform techniques are employed to solve the problem. The integral transform have been inverted by using a numerical technique to obtain the displacements, stresses, temperature distribution, and chemical potential distribution. The numerical results of these quantities are illustrated graphically to depict the response of various sources in the theories of thermoelastic diffusion and thermoelasticity for a particular model. Some particular cases have been deduced from the present investigation.

  15. Plane wave reflection at flow intakes

    NASA Astrophysics Data System (ADS)

    Davies, P. O. A. L.

    1987-06-01

    A treatment is presented for prediction of the acoustic field associated with an open duct termination whose inflow is at a mean Mach number, and requires a quantitative description of both the acoustic and flow conditions in the vicinity of the open end. This problem is presently simplified by restricting the acoustic field within the duct to plane wave motion, with component wave amplitudes p(+) and p(-), where p(+) is incident at the termination. A 'vena contracta' develops in the pipe just downstream of the intake, leading to a significant mean pressure loss.

  16. Optimizing snake locomotion on an inclined plane.

    PubMed

    Wang, Xiaolin; Osborne, Matthew T; Alben, Silas

    2014-01-01

    We develop a model to study the locomotion of snakes on inclined planes. We determine numerically which snake motions are optimal for two retrograde traveling-wave body shapes, triangular and sinusoidal waves, across a wide range of frictional parameters and incline angles. In the regime of large transverse friction coefficients, we find power-law scalings for the optimal wave amplitudes and corresponding costs of locomotion. We give an asymptotic analysis to show that the optimal snake motions are traveling waves with amplitudes given by the same scaling laws found in the numerics.

  17. Braiding patterns on an inclined plane.

    PubMed

    Mertens, Keith; Putkaradze, Vakhtang; Vorobieff, Peter

    2004-07-08

    A jet of fluid flowing down a partially wetting, inclined plane usually meanders but--by maintaining a constant flow rate--meandering can be suppressed, leading to the emergence of a beautiful braided structure. Here we show that this flow pattern can be explained by the interplay between surface tension, which tends to narrow the jet, and fluid inertia, which drives the jet to widen. These observations dispel misconceptions about the relationship between braiding and meandering that have persisted for over 20 years.

  18. X-ray plane-wave diffraction effects in a crystal with third-order nonlinearity

    NASA Astrophysics Data System (ADS)

    Balyan, M. K.

    2016-12-01

    The two-wave dynamical diffraction in the Laue geometry has been theoretically considered for a plane X-ray wave in a crystal with a third-order nonlinear response to the external field. An analytical solution to the problem stated is found for certain diffraction conditions. A nonlinear pendulum effect is analyzed. The nonlinear extinction length is found to depend on the incident-wave intensity. A pendulum effect of a new type is revealed: the intensities of the transmitted and diffracted waves periodically depend on the incidentwave intensity at a fixed crystal thickness. The rocking curves and Borrmann nonlinear effect are numerically calculated.

  19. The motion of charged particles in strong plane waves including radiation reaction

    NASA Astrophysics Data System (ADS)

    Leinemann, R.; Herold, H.; Ruder, H.; Kegel, W. H.

    The Lorentz-Dirac equation in the Landau approximation is used to study the motion of charged particles in strong plane vacuum waves. It is shown that integration for circularly polarized waves can be used to determine analytically the curves of the particle trajectories. The solution is used to investigate the particle trajectories and energy evolution for various strong waves. The initial conditions for the motion are chosen so that the particles start from a radiation-free path and the growing effect of the radiation reaction on the particle trajectory is highlighted.

  20. Symbolism and rationality in the politics of psychoactive substances.

    PubMed

    Room, Robin

    2005-01-01

    Psychoactive substances take on many symbolic meanings, and thus the politics of psychoactive substances has featured symbolic elements, or value-based rationality, alongside and often dominating instrumental rationality. Drawing particularly on the work of Joseph Gusfield and Nordic scholars, the chapter considers the symbolic dimension in the politics of substance use, even in Nordic countries celebrated for their societal commitment to knowledge-based policymaking, and its effects on the interplay of science and policy.

  1. Variation of sensitometric curves of radiographic films in high energy photon beams.

    PubMed

    Danciu, C; Proimos, B S; Rosenwald, J C; Mijnheer, B J

    2001-06-01

    Film dosimetry is an important tool for the verification of irradiation techniques. The shape of the sensitometric curve depends on the type of film as well as on the irradiation and processing conditions. Existing data concerning the influence of irradiation geometry on the sensitometric curve are conflicting. In particular the variation of optical density, OD, with field size and depth in a phantom shows large differences in magnitude between various authors. This variation, as well as the effect of beam energy and film plane orientation on OD, was therefore investigated for two types of film, Kodak X-Omat V and Agfa Structurix D2. Films were positioned in a solid phantom, either perpendicular or (almost) parallel to the beam axis, and irradiated to different dose levels using various photon beams (Co-60, 6 MV, 15 MV, 18 MV, 45 MV). It was found that the sensitometric curves of the Kodak film derived at different depths are almost identical for the four x-ray beams. For the Kodak film the differences in OD with depth are less than 2%, except for the Co-60 beam, where the difference is about 4% at 10 cm depth for a 15 cm x 15 cm field. The slope of the sensitometric curve of the Agfa film is somewhat more dependent on photon beam energy, depth and field size. The sensitometric curves of both types of film are almost independent of the film plane orientation, except for shallow depths. For Co-60 and for the same dose, the Kodak and Agfa films gave at dose maximum an OD lower by 4% and 6%, respectively, for the parallel compared to the perpendicular geometry. Good dosimetric results can be obtained if films from the same batch are irradiated with small to moderate field sizes (up to about 15 cm x 15 cm), at moderate depths (up to about 15 cm), using a single calibration curve, e.g., for a 10 cm x 10 cm field.

  2. Grizzly bear (Ursus arctos horribilis) locomotion: forelimb joint mechanics across speed in the sagittal and frontal planes.

    PubMed

    Shine, Catherine L; Robbins, Charles T; Nelson, O Lynne; McGowan, Craig P

    2017-04-01

    The majority of terrestrial locomotion studies have focused on parasagittal motion and paid less attention to forces or movement in the frontal plane. Our previous research has shown that grizzly bears produce higher medial ground reaction forces (lateral pushing from the animal) than would be expected for an upright mammal, suggesting frontal plane movement may be an important aspect of their locomotion. To examine this, we conducted an inverse dynamics analysis in the sagittal and frontal planes, using ground reaction forces and position data from three high-speed cameras of four adult female grizzly bears. Over the speed range collected, the bears used walks, running walks and canters. The scapulohumeral joint, wrist and the limb overall absorb energy (average total net work of the forelimb joints, -0.97 W kg(-1)). The scapulohumeral joint, elbow and total net work of the forelimb joints have negative relationships with speed, resulting in more energy absorbed by the forelimb at higher speeds (running walks and canters). The net joint moment and power curves maintain similar patterns across speed as in previously studied species, suggesting grizzly bears maintain similar joint dynamics to other mammalian quadrupeds. There is no significant relationship with net work and speed at any joint in the frontal plane. The total net work of the forelimb joints in the frontal plane was not significantly different from zero, suggesting that, despite the high medial ground reaction forces, the forelimb acts as a strut in that plane.

  3. Strain induced modification in phonon dispersion curves of monolayer boron pnictides

    SciTech Connect

    Jha, Prafulla K. E-mail: prafullaj@yahoo.com; Soni, Himadri R.

    2014-01-14

    In the frame work of density functional theory, the biaxial strain induced phonon dispersion curves of monolayer boron pnictides (BX, X = N, P, As, and Sb) have been investigated. The electron-ion interactions have been modelled using ultrasoft pseudopotentials while exchange-correlation energies have been approximated by the method of local density approximation in the parameterization of Perdew-Zunger. The longitudinal and transverse acoustic phonon modes of boron pnictide sheets show linear dependency on wave vector k{sup →} while out of plane mode varies as k{sup 2}. The in-plane longitudinal and out of plane transverse optical modes in boron nitride displaying significant dispersion similar to graphene. We have analyzed the biaxial strain dependent behaviour of out of plane acoustic phonon mode which is linked to ripple for four BX sheets using a model equation with shell elasticity theory. The strain induces the hardening of this mode with tendency to become more linear with increase in strain percentage. The strain induced hardening of out of plane acoustic phonon mode indicates the absence of rippling in these compounds. Our band structure calculations for both unstrained and strained 2D h-BX are consistent with previous calculations.

  4. Tank Tests of a Model of a Flying-boat Hull Having a Longitudinally Concave Planing Bottom

    NASA Technical Reports Server (NTRS)

    Parkinson, J B

    1935-01-01

    The NACA model 11-B, which has a longitudinally concave planing bottom forward of the step, was tested over a wide range of loading. The results of the tests are presented as curves of resistance and trimming moment plotted against speed for various trim angles and as curves of resistance coefficient at best trim angle, and trimming-moment coefficient. The characteristics of the form at the optimum trim are compared with those of NACA model 11-C which has the same form with the exception of a planing bottom longitudinally straight near the step. Photographs of the models being towed in the tank are included for a comparison of the spray patterns. At the best angles of trim in each case model 11-B has lower resistance at high speeds, a higher maximum positive trimming moment near the hump speed, and a more favorable spray pattern than of model 11-C.

  5. The effect of averaging adjacent planes for artifact reduction in matrix inversion tomosynthesis

    SciTech Connect

    Godfrey, Devon J.; Page McAdams, H.; Dobbins, James T. III

    2013-02-15

    Purpose: Matrix inversion tomosynthesis (MITS) uses linear systems theory and knowledge of the imaging geometry to remove tomographic blur that is present in conventional backprojection tomosynthesis reconstructions, leaving in-plane detail rendered clearly. The use of partial-pixel interpolation during the backprojection process introduces imprecision in the MITS modeling of tomographic blur, and creates low-contrast artifacts in some MITS planes. This paper examines the use of MITS slabs, created by averaging several adjacent MITS planes, as a method for suppressing partial-pixel artifacts. Methods: Human chest tomosynthesis projection data, acquired as part of an IRB-approved pilot study, were used to generate MITS planes, three-plane MITS slabs (MITSa3), five-plane MITS slabs (MITSa5), and seven-plane MITS slabs (MITSa7). These were qualitatively examined for partial-pixel artifacts and the visibility of normal and abnormal anatomy. Additionally, small (5 mm) subtle pulmonary nodules were simulated and digitally superimposed upon human chest tomosynthesis projection images, and their visibility was qualitatively assessed in the different reconstruction techniques. Simulated images of a thin wire were used to generate modulation transfer function (MTF) and slice-sensitivity profile curves for the different MITS and MITS slab techniques, and these were examined for indications of partial-pixel artifacts and frequency response uniformity. Finally, mean-subtracted, exposure-normalized noise power spectra (ENNPS) estimates were computed and compared for MITS and MITS slab reconstructions, generated from 10 sets of tomosynthesis projection data of an acrylic slab. The simulated in-plane MTF response of each technique was also combined with the square root of the ENNPS estimate to yield stochastic signal-to-noise ratio (SNR) information about the different reconstruction techniques. Results: For scan angles of 20 Degree-Sign and 5 mm plane separation, seven MITS

  6. PLANING MILL, FIRST FLOOR INTERIOR, LOOKING SOUTH. THE LARGE DEVICE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PLANING MILL, FIRST FLOOR INTERIOR, LOOKING SOUTH. THE LARGE DEVICE IS A WHEEL BORING MACHINE USED DURING THE TIME THIS AREA WAS A WHEEL SHOP. - Southern Pacific, Sacramento Shops, Planing Mill, 111 I Street, Sacramento, Sacramento County, CA

  7. 55. LOOKING EAST FROM HEAD OF PLANE 2 EAST. POWER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    55. LOOKING EAST FROM HEAD OF PLANE 2 EAST. POWER HOUSE AND FLUME VISIBLE TO RIGHT, TAILRACE RUNNING THROUGH CENTER OF PHOTOGRAPH. CRADLE TO INCLINED PLANE 3 EAST IS VISIBLE IN BACKGROUND TO LEFT. - Morris Canal, Phillipsburg, Warren County, NJ

  8. 5. VIEW WEST, PERSPECTIVE UP INCLINED PLANE FROM TOP OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW WEST, PERSPECTIVE UP INCLINED PLANE FROM TOP OF ABUTMENT, FILL CONFIGURATION - Laurel Hill Quarry, Incline Plane, Both sides of State Route 56, 2.4 miles East of State Route 711, Seward, Westmoreland County, PA

  9. 2. VIEW SOUTH, PERSPECTIVE OF ABUTMENT AND INCLINED PLANE ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW SOUTH, PERSPECTIVE OF ABUTMENT AND INCLINED PLANE ON WEST SIDE OF PA ROUTE 56 - Laurel Hill Quarry, Incline Plane, Both sides of State Route 56, 2.4 miles East of State Route 711, Seward, Westmoreland County, PA

  10. 3. VIEW NORTHWEST, PERSPECTIVE OF ABUTMENT AND INCLINED PLANE ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. VIEW NORTHWEST, PERSPECTIVE OF ABUTMENT AND INCLINED PLANE ON WEST SIDE OF PA ROUTE 56 - Laurel Hill Quarry, Incline Plane, Both sides of State Route 56, 2.4 miles East of State Route 711, Seward, Westmoreland County, PA

  11. 6. VIEW WEST, PERSPECTIVE UP INCLINED PLANE FROM MIDSLOPE VICINITY, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. VIEW WEST, PERSPECTIVE UP INCLINED PLANE FROM MID-SLOPE VICINITY, CUT CONFIGURATION - Laurel Hill Quarry, Incline Plane, Both sides of State Route 56, 2.4 miles East of State Route 711, Seward, Westmoreland County, PA

  12. The relationship between rational drug design and drug side effects.

    PubMed

    Wang, Juan; Li, Zhi-xin; Qiu, Cheng-xiang; Wang, Dong; Cui, Qing-hua

    2012-05-01

    Previous analysis of systems pharmacology has revealed a tendency of rational drug design in the pharmaceutical industry. The targets of new drugs tend to be close with the corresponding disease genes in the biological networks. However, it remains unclear whether the rational drug design introduces disadvantages, i.e. side effects. Therefore, it is important to dissect the relationship between rational drug design and drug side effects. Based on a recently released drug side effect database, SIDER, here we analyzed the relationship between drug side effects and the rational drug design. We revealed that the incidence drug side effect is significantly associated with the network distance of drug targets and diseases genes. Drugs with the distances of three or four have the smallest incidence of side effects, whereas drugs with the distances of more than four or smaller than three show significantly greater incidence of side effects. Furthermore, protein drugs and small molecule drugs show significant differences. Drugs hitting membrane targets and drugs hitting cytoplasm targets also show differences. Failure drugs because of severe side effects show smaller network distances than approved drugs. These results suggest that researchers should be prudent on rationalizing the drug design. Too small distances between drug targets and diseases genes may not always be advantageous for rational design for drug discovery.

  13. Generalization of the subsonic kernel function in the s-plane, with applications to flutter analysis

    NASA Technical Reports Server (NTRS)

    Cunningham, H. J.; Desmarais, R. N.

    1984-01-01

    A generalized subsonic unsteady aerodynamic kernel function, valid for both growing and decaying oscillatory motions, is developed and applied in a modified flutter analysis computer program to solve the boundaries of constant damping ratio as well as the flutter boundary. Rates of change of damping ratios with respect to dynamic pressure near flutter are substantially lower from the generalized-kernel-function calculations than from the conventional velocity-damping (V-g) calculation. A rational function approximation for aerodynamic forces used in control theory for s-plane analysis gave rather good agreement with kernel-function results, except for strongly damped motion at combinations of high (subsonic) Mach number and reduced frequency.

  14. Microstructural evolution during tension-compression in-plane deformation of a pure aluminum sheet

    NASA Astrophysics Data System (ADS)

    Härtel, M.; Bohne, B.; F-X Wagner, M.

    2017-03-01

    Classically, the Bauschinger effect refers to a reduction of yield strength after a load path change. In this contribution, we present results of an experimental and microstructural investigation on Bauschinger effects in an AA1050 sheet metal (with 1 mm thickness) subjected to in-plane uniaxial loading. We performed tension-compression tests with different values of maximum tensile strains in a novel tool that was specifically designed to avoid buckling under compressive loading. Our experimental results show that the sheet material exhibits distinct Bauschinger effects. At different stages of deformation, we interrupted the tests and prepared samples for transmission electron microscopy. Our microstructural observations allow rationalizing the occurrence and magnitude of the observed Bauschinger effects.

  15. In-plane and out-of-plane defectivity in thin films of lamellar block copolymers

    DOE PAGES

    Mahadevapuram, Nikhila; Mitra, Indranil; Bozhchenko, Alona; ...

    2015-10-29

    We investigate the ordering of poly(styrene-b-methyl methacrylate) (PS-PMMA) lamellar copolymers (periodicity L0 = 46 nm) confined between a free surface and brushed poly(styrene-r-methyl methacrylate) silicon substrate. The processing temperature was selected to eliminate wetting layers at the top and bottom interfaces, producing approximately neutral boundaries that stabilize perpendicular domain orientations. The PS-PMMA film thickness (t = 0.5L0–2.5L0) and brush grafting density (Σ = 0.2–0.6 nm–2) were systematically varied to examine their impacts on in-plane and out-of-plane ordering. Samples were characterized with a combination of high-resolution microscopy, X-ray reflectivity, and grazing-incidence small-angle X-ray scattering. In-plane order at the top of themore » film (quantified through calculation of orientational correlation lengths) improved with tn, where the exponent n increased from 0.75 to 1 as Σ decreased from 0.6 to 0.2 nm–2. Out-of-plane defects such as tilted domains were detected in all films, and the distribution of domain tilt angles was nearly independent of t and Σ. These studies demonstrate that defectivity in perpendicular lamellar phases is three-dimensional, comprised of in-plane topological defects and out-of-plane domain tilt, with little or no correlation between these two types of disorder. As a result, strong interactions between the block copolymer and underlying substrate may trap both kinds of thermally generated defects.« less

  16. In-plane and out-of-plane defectivity in thin films of lamellar block copolymers

    SciTech Connect

    Mahadevapuram, Nikhila; Mitra, Indranil; Bozhchenko, Alona; Strzalka, Joseph; Stein, Gila E.

    2015-10-29

    We investigate the ordering of poly(styrene-b-methyl methacrylate) (PS-PMMA) lamellar copolymers (periodicity L0 = 46 nm) confined between a free surface and brushed poly(styrene-r-methyl methacrylate) silicon substrate. The processing temperature was selected to eliminate wetting layers at the top and bottom interfaces, producing approximately neutral boundaries that stabilize perpendicular domain orientations. The PS-PMMA film thickness (t = 0.5L0–2.5L0) and brush grafting density (Σ = 0.2–0.6 nm–2) were systematically varied to examine their impacts on in-plane and out-of-plane ordering. Samples were characterized with a combination of high-resolution microscopy, X-ray reflectivity, and grazing-incidence small-angle X-ray scattering. In-plane order at the top of the film (quantified through calculation of orientational correlation lengths) improved with tn, where the exponent n increased from 0.75 to 1 as Σ decreased from 0.6 to 0.2 nm–2. Out-of-plane defects such as tilted domains were detected in all films, and the distribution of domain tilt angles was nearly independent of t and Σ. These studies demonstrate that defectivity in perpendicular lamellar phases is three-dimensional, comprised of in-plane topological defects and out-of-plane domain tilt, with little or no correlation between these two types of disorder. As a result, strong interactions between the block copolymer and underlying substrate may trap both kinds of thermally generated defects.

  17. Phase retrieval in the focal plane

    NASA Astrophysics Data System (ADS)

    Gaessler, W.; Peter, D.; Storz, C.

    Phase retrieval in the focal plane is a very appealing technique, which would simplify the optomechanics of an Adaptive Optics (AO) system a lot and could gain sensitivity under certain conditions. For conventional AO systems the limiting magnitude of the system does not depend on the diameter of the telescope, since any wave front sensor splits the light into sub-apertures, which are in number related to the telescope diameter. Having this in mind the phase retrieval technique looks promising as it breaks this paradigm in the diffraction limited case and thus yields some gain in limiting magnitude with larger telescope diameter. Until now this path was not followed deeply in astronomical AO systems, as the solution of the inversion is non unique and demands much higher calculation power as in conventional AO. This might change with state of the art computers. We give a short overview of some existing techniques and algorithms of focal plane AO and report results of other groups, which tested them in laboratory and on sky. To solve the drawback of the large computational demands and to increase the sensitivity we propose a bootstrapping process with dynamical binning.

  18. Dense granular flows down an inclined plane

    NASA Astrophysics Data System (ADS)

    Ecke, Robert; Borzsonyi, Tamas

    2006-03-01

    Granular flow on a rough inclined plane is an important model system in which to study the basic rules of the dynamics of granular materials. Despite intensive study, many features of such flows are still incompletely understood. For uniformly flowing layers at relatively shallow inclination, we consider experimentally the the basic flow rheology of the granular media and propose new scalings to collapse our data for glass beads and rough sand as a function of inclination angle and particle diameter. At steep inclinations above some angle θs (θs/θr 1.3-1.5, where θr stands for the angle of repose) for flowing grains, numerics and theory predict that the surface roughness is inadequate to dissipate energy gained in the gravitational field, and the flow should continue to accelerate. We report on our experimental results on the properties of granular flows on a steeply inclined plane and define the domains of steady flows. We also discuss the instabilities of such flows leading to spatial patterns.

  19. Trajectory optimization for the National aerospace plane

    NASA Technical Reports Server (NTRS)

    Lu, Ping

    1993-01-01

    While continuing the application of the inverse dynamics approach in obtaining the optimal numerical solutions, the research during the past six months has been focused on the formulation and derivation of closed-form solutions for constrained hypersonic flight trajectories. Since it was found in the research of the first year that a dominant portion of the optimal ascent trajectory of the aerospace plane is constrained by dynamic pressure and heating constraints, the application of the analytical solutions significantly enhances the efficiency in trajectory optimization, provides a better insight to understanding of the trajectory and conceivably has great potential in guidance of the vehicle. Work of this period has been reported in four technical papers. Two of the papers were presented in the AIAA Guidance, Navigation, and Control Conference (Hilton Head, SC, August, 1992) and Fourth International Aerospace Planes Conference (Orlando, FL, December, 1992). The other two papers have been accepted for publication by Journal of Guidance, Control, and Dynamics, and will appear in 1993. This report briefly summarizes the work done in the past six months and work currently underway.

  20. Burnett description for plane Poiseuille flow.

    PubMed

    Uribe, F J; Garcia, A L

    1999-10-01

    Two recent works have shown that at small Knudsen number (K) the pressure and temperature profiles in plane Poiseuille flow exhibit a different qualitative behavior from the profiles obtained by the Navier-Stokes equations. Tij and Santos [J. Stat. Phys. 76, 1399 (1994)] used the Bhatnagar-Gross-Kook model to show that the temperature profile is bimodal and the pressure profile is nonconstant. Malek-Mansour, Baras, and Garcia [Physica A 240, 255 (1997)] qualitatively confirmed these predictions in computer experiments using the direct simulation Monte Carlo method (DSMC). In this paper we compare the DSMC measurements of hydrodynamic variables and non-equilibrium fluxes with numerical solutions of the Burnett equations. Given that they are in better agreement with molecular-dynamics simulations [E. Salomons and M. Mareschal, Phys. Rev. Lett. 69, 269 (1992)] of strong shock waves than Navier-Stokes [F. J. Uribe, R. M. Velasco, and L. S. García-Colín, Phys. Rev. Lett. 81, 2044 (1998)], and that they are second order in Knudsen number suggests that the Burnett equations may provide a better description for large K. We find that for plane Poiseuille flow the Burnett equations do not predict the bimodal temperature profile but do recover many of the other anomalous features (e.g., nonconstant pressure and nonzero parallel heat flux).