Directory of Open Access Journals (Sweden)
Heusel, Hanns
1963-03-01
Full Text Available The last war destroyed a large number of civil works, among which were the Berlin bridges. As the number of these was considerable, it was decided to improve on the original designs and methods of construction, taking advantage of new materials and prestressing techniques. Of the 84 reconstructed bridges, 24 of them have been made in prestressed concrete. This emphasizes what considerable importance was attached to this constructional method at a time when this technology had not yet reached its present day mature development. The rebuilt bridges have spans varying between 25 and 100 ms. Their foundations differ considerably in each particular case. Some consist of pile structures, others are of sheet piling, and others again are caissons. At present the most important prestressed bridge in Berlin is the Disching bridge, which runs over the Havel, and carries the road to Spandau. Its single span is 94 ms long, and the ratio of rise to span is 1/63.1.La última guerra mundial destruyó una serie de obras públicas, entre las cuales se hallaban muchos puentes de Berlín. Como el número de puentes destruidos es considerable, se pensó en mejorar las obras originales y los métodos de construcción, para lo cual se contaban con nuevos materiales y la técnica del pretensado, actualmente en estado de madurez. De las 84 obras que se han reconstruido, 24 son de hormigón pretensado. Esto pone de relieve la importancia que se le dio a este sistema en aquellos momentos en que la técnica de este tipo de construcciones no había alcanzado todavía el actual desarrollo. Los puentes reconstruidos tienen luces que varían de 25 a 100 metros. Los cimientos de estas obras son muy distintos y variados: unos están formados por tablestacas, otros se apoyan sobre pilotes y, finalmente, otros, constituidos por cajones. El puente pretensado más importante actualmente en Berlín es el de Disching, que salva el río Havel y cuyo objeto es el de dar paso a la
Academia de Bellas Artes, en Berlín
Directory of Open Access Journals (Sweden)
Duttmann, Werner
1962-12-01
Full Text Available La Academia de Bellas Artes de Berlín, fundada en 1696, ha ejercido en el transcurso de los siglos una gran influencia sobre la vida artística de la antigua capital alemana. Disuelta en el año 1933, fue creada de nuevo después de la guerra —hacia 1950— en la zona oriental, no pudiendo igualmente renacer en Berlín Oeste hasta 1954. Recientemente se ha construido el nuevo edificio, sede actual de la Academia. Su realización se ha llevado a cabo gracias a la gran ayuda prestada por Henry H. Reichhold, de Nueva York, un alemán nacionalizado norteamericano, que ha contribuido en gran parte al desarrollo cultural de su ciudad natal, Berlín.
Blowout bifurcation of chaotic saddles
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Tomasz Kapitaniak
1999-01-01
Full Text Available Chaotic saddles are nonattracting dynamical invariant sets that can lead to a variety of physical phenomena. We describe the blowout bifurcation of chaotic saddles located in the symmetric invariant manifold of coupled systems and discuss dynamical phenomena associated with this bifurcation.
Saddle scars Existence and applications
Mendes, R V
1998-01-01
A quantum scar is a wave function which displays an high intensity in the region of a classical unstable periodic orbit. Saddle scars are states related to the unstable harmonic motions along the stable manifold of a saddle point of the potential. Using a semiclassical method it is shown that, independently of the overall structure of the potential, the local dynamics of the saddle point is sufficient to insure the general existence of this type of scars and their factorized structure is obtained. Potentially useful situations are identified, where these states appear (directly or in disguise) and might be used for quantum control purposes.
Validación colombiana del cuestionario de Berlín
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Irina Goretty Polanía-Dussan
2013-09-01
Full Text Available Resumen Antecedentes. El síndrome de apnea hipopnea obstructiva del sueño es un cuadro clínico con múltiples comorbilidades y complicaciones. Habitualmente no se diagnostica, por lo cual se debe contar con herramientas que permitan identificar a los pacientes con alto riesgo; entre ellas se encuentra el cuestionario de Berlín. Objetivo. Validar el cuestionario de Berlín en Colombia. Materiales y métodos. Se tomaron individuos que acudieron a centros de sueño en Bogotá y estudiantes universitarios. Seis fases: traducción y retrotraducción del cuestionario de Berlín original, validación de apariencia (expertos, n=14, consistencia interna (n=212, validez de criterio y discriminante (n=212 con polisomnografía paralela, reproducibilidad (n=74. Resultados. El cuestionario de Berlín validado localmente tiene una sensibilidad del 87%, especificidad del 70%, valor predictivo positivo del 98%, valor predictivo negativo del 21%, LR+ 2,9, LR- de 18 y un área bajo la curva de 0,7856. La consistencia interna obtuvo un coeficiente alfa de Cronbach de 0,7257. La reproducibilidad encontró un kappa de 0,8150 (Prob>Z=0,0000. Conclusiones. El cuestionario de Berlín está adaptado a las condiciones de vida urbana de la población adulta colombiana, es sensible, específico y tiene una alta reproducibilidad y consistencia interna, de tal manera que es confiable, válido y se correlaciona con la polisomnografía, en forma clínica y estadísticamente significativa.
La arquitectura de la Groβstadt : Berlín, 1900-1945
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Mónica Vázquez Astorga
2011-01-01
Full Text Available El presente artículo recoge las conclusiones más importantes obtenidas durante mi estancia de investigación realizada en Berlín en el verano de 2009, que tuvo por objeto el estudio y análisis de la actividad arquitectónica desarrollada en Berlín antes y después de la Segunda Guerra Mundial y, en concreto, entre 1900 y 1945. Se valora también el contexto existente en esta ciudad tras las destrucciones ocasionadas por el segundo conflicto mundial, aludiendo a las diversas propuestas ideadas para su reconstrucción. Asimismo, se ha buscado establecer paralelismos con el panorama arquitectónico europeo.The following article includes the most important conclusions drawn from my research stay in Berlin during the summer of 2009. The main aim of my research was to study and analyse the architectural development carried out in Berlin between 1900 and 1945, before and after the II World War, taking also into account the prevailing context of the city due to the damages caused by this War, the numerous reconstruction projects put forward in that moment, together with an attempt to establish parallelisms with the European architectural prospect of that historical moment.
The Antitriangular Factorization of Saddle Point Matrices
Pestana, J.
2014-01-01
Mastronardi and Van Dooren [SIAM J. Matrix Anal. Appl., 34 (2013), pp. 173-196] recently introduced the block antitriangular ("Batman") decomposition for symmetric indefinite matrices. Here we show the simplification of this factorization for saddle point matrices and demonstrate how it represents the common nullspace method. We show that rank-1 updates to the saddle point matrix can be easily incorporated into the factorization and give bounds on the eigenvalues of matrices important in saddle point theory. We show the relation of this factorization to constraint preconditioning and how it transforms but preserves the structure of block diagonal and block triangular preconditioners. © 2014 Society for Industrial and Applied Mathematics.
Deconstructing zero: resurgence, supersymmetry and complex saddles
Dunne, Gerald V.; Ünsal, Mithat
2016-12-01
We explain how a vanishing, or truncated, perturbative expansion, such as often arises in semi-classically tractable supersymmetric theories, can nevertheless be related to fluctuations about non-perturbative sectors via resurgence. We also demonstrate that, in the same class of theories, the vanishing of the ground state energy (unbroken supersymmetry) can be attributed to the cancellation between a real saddle and a complex saddle (with hidden topological angle π), and positivity of the ground state energy (broken supersymmetry) can be interpreted as the dominance of complex saddles. In either case, despite the fact that the ground state energy is zero to all orders in perturbation theory, all orders of fluctuations around non-perturbative saddles are encoded in the perturbative E ( N, g). We illustrate these ideas with examples from supersymmetric quantum mechanics and quantum field theory.
Deconstructing zero: resurgence, supersymmetry and complex saddles
Dunne, Gerald V
2016-01-01
We explain how a vanishing, or truncated, perturbative expansion, such as often arises in semi-classically tractable supersymmetric theories, can nevertheless be related to fluctuations about non-perturbative sectors via resurgence. We also demonstrate that, in the same class of theories, the vanishing of the ground state energy (unbroken supersymmetry) can be attributed to the cancellation between a real saddle and a complex saddle (with hidden topological angle pi), and positivity of the ground state energy (broken supersymmetry) can be interpreted as the dominance of complex saddles. In either case, despite the fact that the ground state energy is zero to all orders in perturbation theory, all orders of fluctuations around non-perturbative saddles are encoded in the perturbative E(N, g). We illustrate these ideas with examples from supersymmetric quantum mechanics and quantum field theory.
Featured Partner: Saddle Creek Logistics Services
This EPA fact sheet spotlights Saddle Creek Logistics as a SmartWay partner committed to sustainability in reducing greenhouse gas emissions and air pollution caused by freight transportation, partly by growing its compressed natural gas (CNG) vehicles for
27 CFR 9.203 - Saddle Rock-Malibu.
2010-04-01
... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Saddle Rock-Malibu. 9.203... Saddle Rock-Malibu. (a) Name. The name of the viticultural area described in this section is “Saddle Rock-Malibu”. For purposes of part 4 of this chapter, “Saddle Rock-Malibu” is a term of...
Memoria de la Shoah: el caso de Berlín
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María Rabe, Ana
2011-12-01
Full Text Available In the framework of memory, this paper investigates the interaction between remembrance and oblivion at a philosophical level, as well as on a historical concrete level in relation to the German memory of the Shoah. In the first part, an analysis of this problem is carried out in dialogue with selected philosophers, sociologists, and historians. In the second part, this question is dealt with in the context of the great public debates which occurred in Germany in the nineties, particularly the debate, in 1993, on the remodelling and re-signification of the «New Guard-House» in Berlin, the polemics provoked by Martin Walser’s discourse in 1998 in Frankfurt, and the debate, from 1989 to 1999, on the plan to build a monument in Berlin for the victims of the Shoah. The paper concludes with a discussion of the force of the Berlin monument in present time.
El trabajo investiga tanto en general a nivel filosófico, como en concreto en el caso de la memoria alemana de la Shoah la interacción entre recuerdo y olvido en el marco del trabajo de la memoria. En la primera parte se lleva a cabo un análisis de este problema en diálogo con filósofos, sociólogos e historiadores escogidos. En la segunda parte se trata esta cuestión en el contexto de los grandes debates públicos que hubo en Alemania en los años 90, particularmente el debate de 1993 sobre la remodelación y resignificación de la «Nueva Guardia» en Berlín, la polémica suscitada por el discurso de Martin Walser en 1998 en Francfort, y el debate entre 1989 y 1999 sobre el plan de construir en Berlín un monumento a las víctimas de la Shoah. El texto termina con una discusión del vigor del monumento berlinés en la actualidad.
Hanford Reach - Strategic Control of Phragmites Within Saddle Mountain Lakes
US Fish and Wildlife Service, Department of the Interior — The Saddle Lakes Fire of 2015 burned 14,200 acres of habitat on Saddle Mountain National Wildlife Refuge, part of the Hanford Reach National Monument. Within the...
36 CFR 34.10 - Saddle and pack animals.
2010-07-01
... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Saddle and pack animals. 34... INTERIOR EL PORTAL ADMINISTRATIVE SITE REGULATIONS § 34.10 Saddle and pack animals. The use of saddle and pack animals is prohibited without a permit from the Superintendent....
Formation of Saddle-Shaped Composite Sheets
Verdinsh, G.; Rocens, K.; Serdyuk, D.
2000-11-01
Based on the deformation model of an unbalanced multilayer composite, changes in bending curvatures of sheet-type composites with nonsymmetric structure relative to the midplane of the sheet, depending on the moisture of layers, are predicted. The bending curvatures of saddle-shaped sheets of wood-based composites are calculated with regard to the physical and mechanical properties, geometrical dimensions, orientation, and distribution of layers. The analytical results are compared with the bending curvatures found experimentally for a four-layered unbalanced composite made of birch veneer. The applied calculation model enables us to determine the values of bending curvatures of saddle-shaped wood composite sheets, which can be used in elaborating the technological recommendations.
Saddle point localization of molecular wavefunctions
Mellau, Georg Ch.; Kyuberis, Alexandra A.; Polyansky, Oleg L.; Zobov, Nikolai; Field, Robert W.
2016-09-01
The quantum mechanical description of isomerization is based on bound eigenstates of the molecular potential energy surface. For the near-minimum regions there is a textbook-based relationship between the potential and eigenenergies. Here we show how the saddle point region that connects the two minima is encoded in the eigenstates of the model quartic potential and in the energy levels of the [H, C, N] potential energy surface. We model the spacing of the eigenenergies with the energy dependent classical oscillation frequency decreasing to zero at the saddle point. The eigenstates with the smallest spacing are localized at the saddle point. The analysis of the HCN ↔ HNC isomerization states shows that the eigenstates with small energy spacing relative to the effective (v1, v3, ℓ) bending potentials are highly localized in the bending coordinate at the transition state. These spectroscopically detectable states represent a chemical marker of the transition state in the eigenenergy spectrum. The method developed here provides a basis for modeling characteristic patterns in the eigenenergy spectrum of bound states.
[Reorientation osteotomy of the trapezial saddle].
Kapandji, Adalbert I; Heim, Urs F A
2002-03-01
At its early stage, the thumb TM osteo-arthritis is occasionally painful during some activities and there are mainly radiological signs, only visible on specific views and with maximum amplitudes. They are the first metacarpal base imperfect reintegration in the trapezium saddle in ante-position and an increased slope angle of 140 degrees. So, the "slippery saddle" of the trapezium induces a metacarpal base subluxation. The goal of the proposed technique is to correct the orientation of the trapezial saddle. The slope angle must return to its normal value of about 125 degrees, thanks to an opening wedge osteotomy into the trapezium, completed with a bony wedge insertion. Proposed for the first time in 1983, and used only once by Dr. Heim, this technique was "rediscovered" recently and used on five patients in ten years. It is easy to do, the only complication being two post-operative radial nerve sensitive branch neuromas. In six cases on seven, the pain disappeared, even if the osteo-arthritis was evolving for the two former cases. The functional recovery was total and the patients were satisfied in most of the cases. In spite of this short series, this technique is worth being used for the early stage of thumb osteo-arthritis, eventually combined with others techniques like tenotomy of the Abductor pollicis longus accessories or different types of ligamentoplasties. It is, in any case, more logical than the first metacarpal osteotomy.
GEODESIC RECONSTRUCTION, SADDLE ZONES & HIERARCHICAL SEGMENTATION
Directory of Open Access Journals (Sweden)
Serge Beucher
2011-05-01
Full Text Available The morphological reconstruction based on geodesic operators, is a powerful tool in mathematical morphology. The general definition of this reconstruction supposes the use of a marker function f which is not necessarily related to the function g to be built. However, this paper deals with operations where the marker function is defined from given characteristic regions of the initial function f, as it is the case, for instance, for the extrema (maxima or minima but also for the saddle zones. Firstly, we show that the intuitive definition of a saddle zone is not easy to handle, especially when digitised images are involved. However, some of these saddle zones (regional ones also called overflow zones can be defined, this definition providing a simple algorithm to extract them. The second part of the paper is devoted to the use of these overflow zones as markers in image reconstruction. This reconstruction provides a new function which exhibits a new hierarchy of extrema. This hierarchy is equivalent to the hierarchy produced by the so-called waterfall algorithm. We explain why the waterfall algorithm can be achieved by performing a watershed transform of the function reconstructed by its initial watershed lines. Finally, some examples of use of this hierarchical segmentation are described.
Saddle point localization of molecular wavefunctions.
Mellau, Georg Ch; Kyuberis, Alexandra A; Polyansky, Oleg L; Zobov, Nikolai; Field, Robert W
2016-09-15
The quantum mechanical description of isomerization is based on bound eigenstates of the molecular potential energy surface. For the near-minimum regions there is a textbook-based relationship between the potential and eigenenergies. Here we show how the saddle point region that connects the two minima is encoded in the eigenstates of the model quartic potential and in the energy levels of the [H, C, N] potential energy surface. We model the spacing of the eigenenergies with the energy dependent classical oscillation frequency decreasing to zero at the saddle point. The eigenstates with the smallest spacing are localized at the saddle point. The analysis of the HCN ↔ HNC isomerization states shows that the eigenstates with small energy spacing relative to the effective (v1, v3, ℓ) bending potentials are highly localized in the bending coordinate at the transition state. These spectroscopically detectable states represent a chemical marker of the transition state in the eigenenergy spectrum. The method developed here provides a basis for modeling characteristic patterns in the eigenenergy spectrum of bound states.
Rotating saddle trap as Foucault's pendulum
Kirillov, Oleg N.; Levi, Mark
2016-01-01
One of the many surprising results found in the mechanics of rotating systems is the stabilization of a particle in a rapidly rotating planar saddle potential. Besides the counterintuitive stabilization, an unexpected precessional motion is observed. In this note, we show that this precession is due to a Coriolis-like force caused by the rotation of the potential. To our knowledge, this is the first example where such a force arises in an inertial reference frame. We also propose a simple mechanical demonstration of this effect.
Taxonomy Icon Data: saddled bichir [Taxonomy Icon
Lifescience Database Archive (English)
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Convergence and Cycling in Walker-type Saddle Search Algorithms
Levitt, Antoine
2016-01-01
Algorithms for computing local minima of smooth objective functions enjoy a mature theory as well as robust and efficient implementations. By comparison, the theory and practice of saddle search is destitute. In this paper we present results for idealized versions of the dimer and gentlest ascent (GAD) saddle search algorithms that show-case the limitations of what is theoretically achievable within the current class of saddle search algorithms: (1) we present an improved estimate on the region of attraction of saddles; and (2) we construct quasi-periodic solutions which indicate that it is impossible to obtain globally convergent variants of dimer and GAD type algorithms.
Complex Saddles in Two-dimensional Gauge Theory
Buividovich, P V; Valgushev, S N
2015-01-01
We study numerically the saddle point structure of two-dimensional (2D) lattice gauge theory, represented by the Gross-Witten-Wadia unitary matrix model. The saddle points are in general complex-valued, even though the original integration variables and action are real. We confirm the trans-series/instanton gas structure in the weak-coupling phase, and identify a new complex-saddle interpretation of non-perturbative effects in the strong-coupling phase. In both phases, eigenvalue tunneling refers to eigenvalues moving off the real interval, into the complex plane, and the weak-to-strong coupling phase transition is driven by saddle condensation.
Relevance of saddle-splay elasticity in complex nematic geometries.
Kos, Žiga; Ravnik, Miha
2016-01-28
We demonstrate the relevance of saddle-splay elasticity in nematic liquid crystalline fluids in the context of complex surface anchoring conditions and the complex geometrical confinement. Specifically, nematic cells with patterns of surface anchoring and colloidal knots are shown as examples where saddle-splay free energy contribution can have a notable role which originates from nonhomogeneous surface anchoring and the varying surface curvature. Patterned nematic cells are shown to exhibit various (meta)stable configurations of nematic field, with relative (meta)stability depending on the saddle-splay. We show that for high enough values of saddle-splay elastic constant K24 a previously unstable conformation can be stabilised, more generally indicating that the saddle-splay can reverse or change the (meta)stability of various nematic structures affecting their phase diagrams. Furthermore, we investigate saddle-splay elasticity in the geometry of highly curved boundaries - the colloidal particle knots in nematic - where the local curvature of the particles induces complex spatial variations of the saddle-splay contributions. Finally, a nematic order parameter tensor based saddle-splay invariant is shown, which allows for the direct calculation of saddle-splay free energy from the Q-tensor, a possibility very relevant for multiple mesoscopic modelling approaches, such as Landau-de Gennes free energy modelling.
Las fronteras en el muro de Berlín: frente, fronda y solitón
Directory of Open Access Journals (Sweden)
David Casado Neira
2008-09-01
Full Text Available El Muro de Berlín ha constituido durante casi tres décadas una de las imágenes más poderosas de la frontera. El muro de hormigón que dividió familias, vecinos, edificios, un país y la geopolítica internacional era además de un símbolo una frontera. Pero como frontera materializa más que una línea de división rígida. Buscando los rastros del Muro descubrimos cómo incluso una frontera de tal materialidad fue a la vez frente (ofensivo/defensivo, fronda (espacio de intercambio y habitabilidad y muro de contención al solitón que genera su desaparición.
Saddle Points in the Auxiliary Field Method
Aono, Hiroki
2009-01-01
Investigations are made on the saddle point calculations (SPC) under the auxiliary field method in path integrations. Two different ways of SPC are considered, Method(I) and Method(II), to be checked in an integral representation of the Gamma function, \\Gamma (N), as a bosonic example and in a four-fermi type of Grassmann integral where one "fermion mass" \\omega_0 differs from the other N-degenerate species. The recipe of Method(I) seems rather complicated than that of (II) superficially, but the case turns out to be opposite in the actual situation. A general formalism allows us to calculate for \\Gamma (N) up to O(1/N^{14}). It is found that both happen to coincide in the bosonic case but in the fermionic case Method(II) shows a huge deviation in the weak coupling region where \\omega_0 \\ll 1.
Acceleration of saddle-point searches with machine learning.
Peterson, Andrew A
2016-08-21
In atomistic simulations, the location of the saddle point on the potential-energy surface (PES) gives important information on transitions between local minima, for example, via transition-state theory. However, the search for saddle points often involves hundreds or thousands of ab initio force calls, which are typically all done at full accuracy. This results in the vast majority of the computational effort being spent calculating the electronic structure of states not important to the researcher, and very little time performing the calculation of the saddle point state itself. In this work, we describe how machine learning (ML) can reduce the number of intermediate ab initio calculations needed to locate saddle points. Since machine-learning models can learn from, and thus mimic, atomistic simulations, the saddle-point search can be conducted rapidly in the machine-learning representation. The saddle-point prediction can then be verified by an ab initio calculation; if it is incorrect, this strategically has identified regions of the PES where the machine-learning representation has insufficient training data. When these training data are used to improve the machine-learning model, the estimates greatly improve. This approach can be systematized, and in two simple example problems we demonstrate a dramatic reduction in the number of ab initio force calls. We expect that this approach and future refinements will greatly accelerate searches for saddle points, as well as other searches on the potential energy surface, as machine-learning methods see greater adoption by the atomistics community.
Saddle point of attachment in jet-crossflow interaction
Zhang, Chenxing; Shi, Junxiang; Ke, Zhaoqing; Chen, Chung-Lung
2017-03-01
Numerical simulation and theoretical analysis were performed to investigate the upstream topology of a jet-crossflow interaction. The numerical results were validated with mathematical theory as well as a juncture flow structure. The upstream critical point satisfies the condition of occurrence for a saddle point of attachment in the horseshoe vortex system. In addition to the classical topology led by a saddle point of separation, a new topology led by a saddle point of attachment was found for the first time in a jet-crossflow interaction. The degeneration of the critical point from separation to attachment is determined by the velocity ratio of the jet over the crossflow, and the boundary layer thickness of the flat plate. When the boundary layer thickness at the upstream edge of the jet is close to one diameter of the jet, the flow topology is led by a saddle point of attachment. Variation of the velocity ratio does not change the topology but the location of the saddle point. When the boundary layer thickness is less than 0.255 of the jet flow diameter, large velocity ratio can generate a saddle point of attachment without spiral horseshoe vortex; continuously decreasing the velocity ratio will change the flow topology to saddle point of the separation. The degeneration of the critical point from attachment to separation was observed.
Acceleration of saddle-point searches with machine learning
Peterson, Andrew A.
2016-08-01
In atomistic simulations, the location of the saddle point on the potential-energy surface (PES) gives important information on transitions between local minima, for example, via transition-state theory. However, the search for saddle points often involves hundreds or thousands of ab initio force calls, which are typically all done at full accuracy. This results in the vast majority of the computational effort being spent calculating the electronic structure of states not important to the researcher, and very little time performing the calculation of the saddle point state itself. In this work, we describe how machine learning (ML) can reduce the number of intermediate ab initio calculations needed to locate saddle points. Since machine-learning models can learn from, and thus mimic, atomistic simulations, the saddle-point search can be conducted rapidly in the machine-learning representation. The saddle-point prediction can then be verified by an ab initio calculation; if it is incorrect, this strategically has identified regions of the PES where the machine-learning representation has insufficient training data. When these training data are used to improve the machine-learning model, the estimates greatly improve. This approach can be systematized, and in two simple example problems we demonstrate a dramatic reduction in the number of ab initio force calls. We expect that this approach and future refinements will greatly accelerate searches for saddle points, as well as other searches on the potential energy surface, as machine-learning methods see greater adoption by the atomistics community.
Universal behavior in the parametric evolution of chaotic saddles.
Lai, Y C; Zyczkowski, K; Grebogi, C
1999-05-01
Chaotic saddles are nonattracting dynamical invariant sets that physically lead to transient chaos. As a system parameter changes, chaotic saddles can evolve via an infinite number of homoclinic or heteroclinic tangencies of their stable and unstable manifolds. Based on previous numerical evidence and a rigorous analysis of a class of representative models, we show that dynamical invariants such as the topological entropy and the fractal dimension of chaotic saddles obey a universal behavior: they exhibit a devil-staircase characteristic as a function of the system parameter.
Universal behavior in the parametric evolution of chaotic saddles
Energy Technology Data Exchange (ETDEWEB)
Lai, Y. [Department of Physics and Astronomy and Department of Mathematics, University of Kansas, Lawrence, Kansas 66045 (United States); Zyczkowski, K.; Grebogi, C. [Institute for Plasma Research, University of Maryland, College Park, Maryland 20742 (United States); Zyczkowski, K. [Instytut Fizyki im. Smoluchowskiego, Uniwersytet Hagiellonski, ulica Reymonta 4, 30-059 Krakow (Poland); Grebogi, C. [Department of Mathematics and Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742 (United States)
1999-05-01
Chaotic saddles are nonattracting dynamical invariant sets that physically lead to transient chaos. As a system parameter changes, chaotic saddles can evolve via an infinite number of homoclinic or heteroclinic tangencies of their stable and unstable manifolds. Based on previous numerical evidence and a rigorous analysis of a class of representative models, we show that dynamical invariants such as the topological entropy and the fractal dimension of chaotic saddles obey a universal behavior: they exhibit a devil-staircase characteristic as a function of the system parameter. {copyright} {ital 1999} {ital The American Physical Society}
Complex saddles in the Gross-Witten-Wadia matrix model
Álvarez, Gabriel; Medina, Elena
2016-01-01
We give an exhaustive characterization of the complex saddle point configurations of the Gross-Witten-Wadia matrix model in the large-N limit. In particular, we characterize the cases in which the saddles accumulate in one, two, or three arcs, in terms of the values of the coupling constant and of the fraction of the total unit density that is supported in one of the arcs, and derive an explicit condition for gap closing associated to nonvacuum saddles. By applying the idea of large-N instanton we also give direct analytic derivations of the weak-coupling and strong-coupling instanton actions.
Saddle antenna radio frequency ion sources
Energy Technology Data Exchange (ETDEWEB)
Dudnikov, V., E-mail: vadim@muonsinc.com; Johnson, R. [Muons, Inc., Batavia, Illinois 60510 (United States); Murray, S.; Pennisi, T.; Santana, M.; Piller, C.; Stockli, M.; Welton, R. [ORNL, Oak Ridge, Tennessee 37831 (United States); Breitschopf, J. [TLU, Seguin, Texas 78155 (United States); Dudnikova, G. [UMD, College Park, Maryland 32611 (United States); Institute of Computational Technologies SBRAS, Novosibirsk (Russian Federation)
2016-02-15
Existing RF ion sources for accelerators have specific efficiencies for H{sup +} and H{sup −} ion generation ∼3–5 mA/cm{sup 2} kW, where about 50 kW of RF power is typically needed for 50 mA beam current production. The Saddle Antenna (SA) surface plasma source (SPS) described here was developed to improve H{sup −} ion production efficiency, reliability, and availability. In SA RF ion source, the efficiency of positive ion generation in the plasma has been improved to 200 mA/cm{sup 2} kW. After cesiation, the current of negative ions to the collector was increased from 1 mA to 10 mA with RF power ∼1.5 kW in the plasma (6 mm diameter emission aperture) and up to 30 mA with ∼4 kW RF. Continuous wave (CW) operation of the SA SPS has been tested on the test stand. The general design of the CW SA SPS is based on the pulsed version. Some modifications were made to improve the cooling and cesiation stability. CW operation with negative ion extraction was tested with RF power up to ∼1.2 kW in the plasma with production up to Ic = 7 mA. A stable long time generation of H{sup −} beam without degradation was demonstrated in RF discharge with AlN discharge chamber.
The Trail Inventory of Saddle Mountain NWR [Cycle 3
US Fish and Wildlife Service, Department of the Interior — The purpose of this report is to create a baseline inventory of all non-motorized trails on Saddle Mountain National Wildlife Refuge. Trails in this inventory are...
Time delays across saddles as a test of modified gravity
Magueijo, Joao
2012-01-01
Modified gravity theories can produce strong signals in the vicinity of the saddles of the total gravitational potential. In a sub-class of these models this translates into diverging time-delays for echoes crossing the saddles. Such models arise from the possibility that gravity might be infrared divergent or confined, and if suitably designed they are very difficult to rule out. We show that Lunar Laser Ranging during an eclipse could probe the time-delay effect within meters of the saddle, thereby proving or excluding these models. Very Large Baseline Interferometry, instead, could target delays across the Jupiter-Sun saddle. Such experiments would shed light on the infrared behaviour of gravity and examine the puzzling possibility that there might be well-hidden regions of strong gravity and even singularities inside the solar system.
Institute of Scientific and Technical Information of China (English)
De Ming ZHU; Ying SUN
2007-01-01
In this paper,we study the dynamical behavior for a 4-dimensional reversible system near its heteroclinic loop connecting a saddle-focus and a saddle.The existence of in nitely many reversible 1-homoclinic orbits to the saddle and 2-homoclinic orbits to the saddle-focus is shown.And it is also proved that,corresponding to each 1-homoclinic (resp.2-homoclinic)orbit Γ,there is a spiral segment such that the associated orbits starting from the segment are all reversible 1-periodic (resp.2-periodic)and accumulate onto Γ.Moreover,each 2-homoclinic orbit may be also accumulated by a sequence of reversible 4-homoclinic orbits.
Natural Preconditioning and Iterative Methods for Saddle Point Systems
Pestana, Jennifer
2015-01-01
© 2015 Society for Industrial and Applied Mathematics. The solution of quadratic or locally quadratic extremum problems subject to linear(ized) constraints gives rise to linear systems in saddle point form. This is true whether in the continuous or the discrete setting, so saddle point systems arising from the discretization of partial differential equation problems, such as those describing electromagnetic problems or incompressible flow, lead to equations with this structure, as do, for example, interior point methods and the sequential quadratic programming approach to nonlinear optimization. This survey concerns iterative solution methods for these problems and, in particular, shows how the problem formulation leads to natural preconditioners which guarantee a fast rate of convergence of the relevant iterative methods. These preconditioners are related to the original extremum problem and their effectiveness - in terms of rapidity of convergence - is established here via a proof of general bounds on the eigenvalues of the preconditioned saddle point matrix on which iteration convergence depends.
Chaotic saddles in nonlinear modulational interactions in a plasma
Energy Technology Data Exchange (ETDEWEB)
Miranda, Rodrigo A. [Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), Sao Jose dos Campos, SP 12228-900 (Brazil); National Institute for Space Research (INPE) and World Institute for Space Environment Research (WISER), P.O. Box 515, Sao Jose dos Campos, SP 12227-010 (Brazil); University of Brasilia (UnB), Gama Campus, and Plasma Physics Laboratory, Institute of Physics, Brasilia, DF 70910-900 (Brazil); Rempel, Erico L. [Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), Sao Jose dos Campos, SP 12228-900 (Brazil); National Institute for Space Research (INPE) and World Institute for Space Environment Research (WISER), P.O. Box 515, Sao Jose dos Campos, SP 12227-010 (Brazil); Chian, Abraham C.-L. [Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), Sao Jose dos Campos, SP 12228-900 (Brazil); National Institute for Space Research (INPE) and World Institute for Space Environment Research (WISER), P.O. Box 515, Sao Jose dos Campos, SP 12227-010 (Brazil); Observatoire de Paris, LESIA, CNRS, 92195 Meudon (France)
2012-11-15
A nonlinear model of modulational processes in the subsonic regime involving a linearly unstable wave and two linearly damped waves with different damping rates in a plasma is studied numerically. We compute the maximum Lyapunov exponent as a function of the damping rates in a two-parameter space, and identify shrimp-shaped self-similar structures in the parameter space. By varying the damping rate of the low-frequency wave, we construct bifurcation diagrams and focus on a saddle-node bifurcation and an interior crisis associated with a periodic window. We detect chaotic saddles and their stable and unstable manifolds, and demonstrate how the connection between two chaotic saddles via coupling unstable periodic orbits can result in a crisis-induced intermittency. The relevance of this work for the understanding of modulational processes observed in plasmas and fluids is discussed.
Chaotic saddles in nonlinear modulational interactions in a plasma
Miranda, Rodrigo A; Chian, Abraham C -L
2012-01-01
A nonlinear model of modulational processes in the subsonic regime involving a linearly unstable wave and two linearly damped waves with different damping rates in a plasma is studied numerically. We compute the maximum Lyapunov exponent as a function of the damping rates in a two-parameter space, and identify shrimp-shaped self-similar structures in the parameter space. By varying the damping rate of the low-frequency wave, we construct bifurcation diagrams and focus on a saddle-node bifurcation and an interior crisis associated with a periodic window. We detect chaotic saddles and their stable and unstable manifolds, and demonstrate how the connection between two chaotic saddles via coupling unstable periodic orbits can result in a crisis-induced intermittency. The relevance of this work for the understanding of modulational processes observed in plasmas and fluids is discussed.
Sampling saddle points on a free energy surface.
Samanta, Amit; Chen, Ming; Yu, Tang-Qing; Tuckerman, Mark; E, Weinan
2014-04-28
Many problems in biology, chemistry, and materials science require knowledge of saddle points on free energy surfaces. These saddle points act as transition states and are the bottlenecks for transitions of the system between different metastable states. For simple systems in which the free energy depends on a few variables, the free energy surface can be precomputed, and saddle points can then be found using existing techniques. For complex systems, where the free energy depends on many degrees of freedom, this is not feasible. In this paper, we develop an algorithm for finding the saddle points on a high-dimensional free energy surface "on-the-fly" without requiring a priori knowledge the free energy function itself. This is done by using the general strategy of the heterogeneous multi-scale method by applying a macro-scale solver, here the gentlest ascent dynamics algorithm, with the needed force and Hessian values computed on-the-fly using a micro-scale model such as molecular dynamics. The algorithm is capable of dealing with problems involving many coarse-grained variables. The utility of the algorithm is illustrated by studying the saddle points associated with (a) the isomerization transition of the alanine dipeptide using two coarse-grained variables, specifically the Ramachandran dihedral angles, and (b) the beta-hairpin structure of the alanine decamer using 20 coarse-grained variables, specifically the full set of Ramachandran angle pairs associated with each residue. For the alanine decamer, we obtain a detailed network showing the connectivity of the minima obtained and the saddle-point structures that connect them, which provides a way to visualize the gross features of the high-dimensional surface.
Directory of Open Access Journals (Sweden)
Alexandre de Paula Meirelles
2015-03-01
Full Text Available O presente trabalho tem como intenção estabelecer uma conceituação a respeito da tecnocracia dentro da História Contemporânea do Capitalismo utilizando-se das reflexões feitas pelo marxista João Bernardo e a posteriori estabelecer um estudo comparado e introdutório sobre a política tecnocrática e corporativista nas obras de Adolf Augustus Berle Junior e Walther Rathenau.
Electrons at the monkey saddle: A multicritical Lifshitz point
Shtyk, A.; Goldstein, G.; Chamon, C.
2017-01-01
We consider two-dimensional interacting electrons at a monkey saddle with dispersion ∝px3-3 pxpy2 . Such a dispersion naturally arises at the multicritical Lifshitz point when three Van Hove saddles merge in an elliptical umbilic elementary catastrophe, which we show can be realized in biased bilayer graphene. A multicritical Lifshitz point of this kind can be identified by its signature Landau level behavior Em∝(Bm ) 3 /2 and related oscillations in thermodynamic and transport properties, such as de Haas-Van Alphen and Shubnikov-de Haas oscillations, whose period triples as the system crosses the singularity. We show, in the case of a single monkey saddle, that the noninteracting electron fixed point is unstable to interactions under the renormalization-group flow, developing either a superconducting instability or non-Fermi-liquid features. Biased bilayer graphene, where there are two non-nested monkey saddles at the K and K' points, exhibits an interplay of competing many-body instabilities, namely, s -wave superconductivity, ferromagnetism, and spin- and charge-density waves.
Using saddle points for challenging optical design tasks
Livshits, I.; Hou, Z.; Grol, P. van; Shao, Y.; Turnhout, M. van; Urbach, H.P.; Bociort, F.
2014-01-01
The present research is part of an effort to develop tools that make the lens design process more systematic. In typical optical design tasks, the presence of many local minima in the optical merit function landscape makes design non-trivial. With the method of Saddle Point Construction (SPC) which
Evaluation of saddle and driving aptitudes in Monterufoli pony
Directory of Open Access Journals (Sweden)
Riccardo Bozzi
2010-01-01
Full Text Available The Monterufoli pony is an endangered Tuscan breed. In the 80’s began a project for the conservation of the breed and at present there are roughly 200 individuals. The equine was once utilized for saddle and driving and this study deals with the training for these two aptitudes. The mor- phologic type of the pony seems suited for saddle, in particular for children and beginners, and driving. The ponies showed developed chest, strong legs with short shanks: all these characters were useful for trot and driving. In this trial 3-4 years old never tamed Monterufoli ponies were opportunely choose and subsequently trained for saddle and driving. The ponies were submitted to the “aptitude test” for the two aptitudes and the results were good both for practical and character sides. The marks for sad- dle and driving were 8.16 and 8.06 respectively. Also the 3 ponies showed good results for the Aptitude Index: 7.60, 7.87 and 7.89. The results of the trial showed the excellent ability of the Monterufoli pony for saddle and driving. The good results of the test are important for the diffusion of the breed in the territory and in particular in horse centres and in equestrian tourism sites.
Rotating saddle trap: A Coriolis force in an inertial frame
Kirillov, Oleg N
2015-01-01
Particles in rotating saddle potentials exhibit precessional motion which, up to now, has been explained by explicit computation. We show that this precession is due to a hidden Coriolis-like force which, unlike the standard Coriolis force, is present in the inertial frame. We do so by finding a hodograph-like "guiding center" transformation using the method of normal form.
Practical guide to saddle-point construction in lens design
Bociort, F.; Van Turnhout, M.; Marinescu, O.
2007-01-01
Saddle-point construction (SPC) is a new method to insert lenses into an existing design. With SPC, by inserting and extracting lenses new system shapes can be obtained very rapidly, and we believe that, if added to the optical designer’s arsenal, this new tool can significantly increase design prod
Intermittency and Jakobson's theorem near saddle-node bifurcations
Homburg, A.J.; Young, T.
2007-01-01
Abstract. We discuss one parameter families of unimodal maps, with negative Schwarzian derivative, unfolding a saddle-node bifurcation. We show that there is a parameter set of positive but not full Lebesgue density at the bifurcation, for which the maps exhibit absolutely continuous invariant measu
Saddle-point approach to the gauge Potts model
Energy Technology Data Exchange (ETDEWEB)
Camarata, C.; Epele, L.N.; Fanchiotti, H.; Garcia Canal, C.A.
1984-07-02
The q-state gauge Potts model in d dimensions is studied via saddle-point techniques. Corrections to the mean-field results, due to gaussian fluctuations, are computed. Results for the free energy, the critical coupling and the latent heat are presented. The limit q->infinite is discussed.
19 CFR 148.32 - Vehicles, aircraft, boats, teams and saddle horses taken abroad.
2010-04-01
... 19 Customs Duties 2 2010-04-01 2010-04-01 false Vehicles, aircraft, boats, teams and saddle horses... for Returning Residents § 148.32 Vehicles, aircraft, boats, teams and saddle horses taken abroad. (a) Admission free of duty. Automobiles and other vehicles, aircraft, boats, teams and saddle horses,...
Surface plasma source with saddle antenna radio frequency plasma generator.
Dudnikov, V; Johnson, R P; Murray, S; Pennisi, T; Piller, C; Santana, M; Stockli, M; Welton, R
2012-02-01
A prototype RF H(-) surface plasma source (SPS) with saddle (SA) RF antenna is developed which will provide better power efficiency for high pulsed and average current, higher brightness with longer lifetime and higher reliability. Several versions of new plasma generators with small AlN discharge chambers and different antennas and magnetic field configurations were tested in the plasma source test stand. A prototype SA SPS was installed in the Spallation Neutron Source (SNS) ion source test stand with a larger, normal-sized SNS AlN chamber that achieved unanalyzed peak currents of up to 67 mA with an apparent efficiency up to 1.6 mA∕kW. Control experiments with H(-) beam produced by SNS SPS with internal and external antennas were conducted. A new version of the RF triggering plasma gun has been designed. A saddle antenna SPS with water cooling is fabricated for high duty factor testing.
Thermal Fission Rate Calculated Numerically by Particles Multi-passing over Saddle Point
Institute of Scientific and Technical Information of China (English)
LIU Ling; BAO Jing-Dong
2004-01-01
Langevin simulation of the particles multi-passing over the saddle point is proposed to calculate thermal fission rate. Due to finite friction and the corresponding thermal fluctuation, a backstreaming exists in the process of the particle descent from the saddle to the scission. This leads to that the diffusion behind the saddle point has influence upon the stationary flow across the saddle point. A dynamical correction factor, as a ratio of the flows of multi- and firstoverpassing the saddle point, is evaluated analytically. The results show that the fission rate calculated by the particles multi-passing over the saddle point is lower than the one calculated by the particle firstly passing over the saddle point,and the former approaches the results at the scission point.
Shell Correction at the Saddle Point for Superheavy Nucleus
Institute of Scientific and Technical Information of China (English)
张炜; 张时声; 张双全; 孟杰
2003-01-01
The potential energy surface for superheavy nucleus has been studied within the framework of the constrained relativistic mean field theory, and the shell correction energy as a function of deformation has been extracted by the Strutinsky shell correction procedure. Contrary to the usual expectation, the shell correction energy at the saddle point is too important to be neglected, and it has essential contribution to the fission barrier in superheavy nucleus.
Late Quaternary deformation, Saddle Mountains anticline, south-central Washington
West, M. W.; Ashland, F. X.; Busacca, A. J.; Berger, G. W.; Shaffer, M. E.
1996-12-01
Grabens and beheaded streams above a subjacent thrust fault illuminate late Quaternary deformation on the north limb of the Saddle Mountains anticline, Yakima fold belt, Washington. Geologic mapping and trenches excavated across a scarp on the north flank of a 13-km-long graben and a ± 5-m-high scarp north of the graben, confirm that deformation is related to coseismic slip on the underlying Saddle Mountains fault. Graben development began ca. 100 ka and continued into the Holocene. At least 6.5 m of vertical displacement in a ca. 20 40 ka paleosol yields minimum normal fault slip rates of 0.16 0.33 mm/yr. Assuming that normal slip in the hanging wall above the daylighting fault tip is related to primary reverse slip on the fault, resolution of throw on the 30°-dipping Saddle Mountains fault yields minimum slip of 13 m and minimum slip rates of 0.33 0.65 mm/yr, 2.3 9.4 times greater than slip rates used in a recent seismic hazard analysis for the Hanford Reservation.
Acute Paraplegia as a Presentation of Aortic Saddle Embolism
Directory of Open Access Journals (Sweden)
Lisandro Irizarry
2016-01-01
Full Text Available Background. Acute onset paraplegia has a myriad of causes most often of a nonvascular origin. Vascular etiologies are infrequent causes and most often associated with postsurgical complications. Objective. To describe the occurrence and possible mechanism for aortic saddle embolism as a rare cause of acute paraplegia. Case Report. Described is a case of a 46-year-old female who presented with the sudden onset of nontraumatic low back pain with rapidly progressive paraplegia which was subsequently determined to be of vascular origin.
Triangular preconditioners for saddle point problems with a penalty term
Energy Technology Data Exchange (ETDEWEB)
Klawonn, A. [Westfaelische Wilhelms-Universitaet, Muenster (Germany)
1996-12-31
Triangular preconditioners for a class of saddle point problems with a penalty term are considered. An important example is the mixed formulation of the pure displacement problem in linear elasticity. It is shown that the spectrum of the preconditioned system is contained in a real, positive interval, and that the interval bounds can be made independent of the discretization and penalty parameters. This fact is used to construct bounds of the convergence rate of the GMRES method used with an energy norm. Numerical results are given for GMRES and BI-CGSTAB.
Computation of saddle-type slow manifolds using iterative methods
DEFF Research Database (Denmark)
Kristiansen, Kristian Uldall
2015-01-01
This paper presents an alternative approach for the computation of trajectory segments on slow manifolds of saddle type. This approach is based on iterative methods rather than collocation-type methods. Compared to collocation methods, which require mesh refinements to ensure uniform convergence...... with respect to , appropriate estimates are directly attainable using the method of this paper. The method is applied to several examples, including a model for a pair of neurons coupled by reciprocal inhibition with two slow and two fast variables, and the computation of homoclinic connections in the Fitz...
Maximal Saddle Solution of a Nonlinear Elliptic Equation Involving the -Laplacian
Indian Academy of Sciences (India)
Huahui Yan; Zhuoran Du
2014-02-01
A saddle solution is called maximal saddle solution if its absolute value is not smaller than those absolute values of any solutions that vanish on the Simons cone $\\mathcal{C} = \\{s = t\\}$ and have the same sign as - . We prove the existence of a maximal saddle solution of the nonlinear elliptic equation involving the -Laplacian, by using the method of monotone iteration, $$-_{p^u}=f(u) \\quad \\text{in} \\quad R^{2m},$$ where $2m≥ p > 2$.
Complex Path Integrals and Saddles in Two-Dimensional Gauge Theory.
Buividovich, P V; Dunne, Gerald V; Valgushev, S N
2016-04-01
We study numerically the saddle point structure of two-dimensional lattice gauge theory, represented by the Gross-Witten-Wadia unitary matrix model. The saddle points are, in general, complex valued, even though the original integration variables and action are real. We confirm the trans-series and instanton gas structure in the weak-coupling phase, and we identify a new complex-saddle interpretation of nonperturbative effects in the strong-coupling phase. In both phases, eigenvalue tunneling refers to eigenvalues moving off the real interval, into the complex plane, and the weak-to-strong coupling phase transition is driven by saddle condensation.
Lassoing saddle splay and the geometrical control of topological defects
Tran, Lisa; Lavrentovich, Maxim O.; Beller, Daniel A.; Li, Ningwei; Stebe, Kathleen J.; Kamien, Randall D.
2016-06-01
Systems with holes, such as colloidal handlebodies and toroidal droplets, have been studied in the nematic liquid crystal (NLC) 4-cyano-4'-pentylbiphenyl (5CB): Both point and ring topological defects can occur within each hole and around the system while conserving the system's overall topological charge. However, what has not been fully appreciated is the ability to manipulate the hole geometry with homeotropic (perpendicular) anchoring conditions to induce complex, saddle-like deformations. We exploit this by creating an array of holes suspended in an NLC cell with oriented planar (parallel) anchoring at the cell boundaries. We study both 5CB and a binary mixture of bicyclohexane derivatives (CCN-47 and CCN-55). Through simulations and experiments, we study how the bulk saddle deformations of each hole interact to create defect structures, including an array of disclination lines, reminiscent of those found in liquid-crystal blue phases. The line locations are tunable via the NLC elastic constants, the cell geometry, and the size and spacing of holes in the array. This research lays the groundwork for the control of complex elastic deformations of varying length scales via geometrical cues in materials that are renowned in the display industry for their stability and easy manipulability.
A saddle-point theorem for strongly and weakly convex functions
Ivanov, G. E.
2011-01-01
We prove a theorem on the existence, uniqueness, and continuous dependence on parameters for a saddle point in a type of minimax problem that arises, for example, in differential game theory. Our theorem on the existence of a saddle point does not follow from the well-known theorems of von Neumann,
A method for finding the ridge between saddle points applied to rare event rate estimates
DEFF Research Database (Denmark)
Maronsson, Jon Bergmann; Jónsson, Hannes; Vegge, Tejs
2012-01-01
A method is presented for finding the ridge between first order saddle points on a multidimensional surface. For atomic scale systems, such saddle points on the energy surface correspond to atomic rearrangement mechanisms. Information about the ridge can be used to test the validity of the harmon...
Uniqueness of Limit Cycle for the Quadratic Systems with Weak Saddle and Focus
Institute of Scientific and Technical Information of China (English)
Shen Qi ZHAO; Ping Guang ZHANG
2004-01-01
It is proved that the quadratic system with a weak saddle has at most one limit cycle, and that if this system has a separatrix cycle passing through the weak saddle, then the stability of the separatrix cycle is contrary to that of the singular point surrounded by it.
SADDLE HORSE AND OTHER LIVESTOCK ADVISORS' PERCEPTIONS OF 4-H CLUB WORK IN OHIO.
GROVES, ROBERT H.
PERCEPTIONS AND UNDERSTANDINGS OF 4-H OBJECTIVES AND PROGRAMS OF 4-H SADDLE HORSE ADVISORS WERE COMPARED WITH THOSE OF OTHER LIVESTOCK ADVISORS IN NORTHEASTERN AND SOUTHWESTERN DISTRICTS OF OHIO. DATA WERE COLLECTED BY QUESTIONNAIRES FROM 90 SADDLE HORSE AND 133 OTHER LIVESTOCK ADVISORS. STATE 4-H STAFF AND SUPERVISORS PROVIDED CORRECT ANSWERS.…
Using a new saddle model for echinotherapy therapy.
Directory of Open Access Journals (Sweden)
Carlos Cesar Santín Alfaro
2014-09-01
Full Text Available A descriptive study with experimental design was done, having as an objective to elaborate a new riding saddle model in the Provincial Laboratory of Technical Orthopaedics in the province of Sancti Spiritus for the Echinotherapy´s treatment in disable patients that still assisting to this kind of alternative therapy having the necessity of obtaining the frame according to the adequate characteristics and adjusting to the requirements of the qualified staff that takes care of this task taking into consideration that for the rehabilitation of these children they should be closer to the horse skin. The frame was not made with the row materials of normal chair but with the one adequate in our Laboratory. Some important characteristics were developed in this kind of therapy, and was analyzed the characteristics of the frame use give to patients, offering an immediate solution to their problems in order to solve this difficulty in our province.
Saddle stresses for generic theories with a preferred acceleration scale
Magueijo, Joao
2012-01-01
We show how scaling arguments may be used to generate templates for the tidal stresses around saddles for a vast class of MONDian theories {\\it detached from their obligations as dark matter alternatives}. Such theories are to be seen simply as alternative theories of gravity with a preferred acceleration scale, and could be tested in the solar system by extending the LISA Pathfinder mission. The constraints thus obtained may then be combined, if one wishes, with requirements arising from astrophysical and cosmological applications, but a clear separation of the issues is achieved. The central technical content of this paper is the derivation of a scaling prescription allowing complex numerical work to be bypassed in the generation of templates.
Polymer quantization and the saddle point approximation of partition functions
Morales-Técotl, Hugo A.; Orozco-Borunda, Daniel H.; Rastgoo, Saeed
2015-11-01
The saddle point approximation of the path integral partition functions is an important way of deriving the thermodynamical properties of black holes. However, there are certain black hole models and some mathematically analog mechanical models for which this method cannot be applied directly. This is due to the fact that their action evaluated on a classical solution is not finite and its first variation does not vanish for all consistent boundary conditions. These problems can be dealt with by adding a counterterm to the classical action, which is a solution of the corresponding Hamilton-Jacobi equation. In this work we study the effects of polymer quantization on a mechanical model presenting the aforementioned difficulties and contrast it with the above counterterm method. This type of quantization for mechanical models is motivated by the loop quantization of gravity, which is known to play a role in the thermodynamics of black hole systems. The model we consider is a nonrelativistic particle in an inverse square potential, and we analyze two polarizations of the polymer quantization in which either the position or the momentum is discrete. In the former case, Thiemann's regularization is applied to represent the inverse power potential, but we still need to incorporate the Hamilton-Jacobi counterterm, which is now modified by polymer corrections. In the latter, momentum discrete case, however, such regularization could not be implemented. Yet, remarkably, owing to the fact that the position is bounded, we do not need a Hamilton-Jacobi counterterm in order to have a well-defined saddle point approximation. Further developments and extensions are commented upon in the discussion.
Investigation of saddle trajectories for cardiac CT imaging in cone-beam geometry
Energy Technology Data Exchange (ETDEWEB)
Pack, Jed D [Department of Radiology, University of Utah, Salt Lake City, UT 84112 (United States); Noo, Frederic [Department of Radiology, University of Utah, Salt Lake City, UT 84112 (United States); Kudo, H [Department of Computer Science, Graduate School of Systems and Information Engineering, University of Tsukuba (Japan)
2004-06-07
This paper investigates cone-beam tomography for a wide class of x-ray source trajectories called saddles. In particular, a mathematical analysis of the number of intersections between a saddle and an arbitrary plane is given. This analysis demonstrates that axially truncated cone-beam projections acquired along a saddle can be used for exact reconstruction at any point in a large volume. The reconstruction can be achieved either using a new algorithm presented herein or using a formula recently introduced by Katsevich (2003 Int. J. Math. Math. Sci. 21 1305-21). The shape of the reconstructed volume and the properties of saddles make saddles attractive for cardiac imaging. Three examples of saddles are presented with a discussion of implementation on devices similar to modern C-arm systems and multislice CT scanners. Reconstruction with one of these saddles has been tested using computer-simulated data, with and without truncation. The imaged phantom for the truncated data is a FORBILD head phantom (representing the heart) that has been modified and embedded inside the FORBILD thorax phantom. The non-truncated data were generated by excluding the thorax. The reconstructed images demonstrate the accuracy of the mathematical results.
Integrability of Liénard systems with a weak saddle
Gasull, Armengol; Giné, Jaume
2017-02-01
We characterize the local analytic integrability of weak saddles for complex Liénard systems, dot{x}=y-F(x), dot{y}= ax, 0≠ ain C, with F analytic at 0 and F(0)=F'(0)=0. We prove that they are locally integrable at the origin if and only if F( x) is an even function. This result implies the well-known characterization of the centers for real Liénard systems. Our proof is based on finding the obstructions for the existence of a formal integral at the complex saddle, by computing the so-called resonant saddle quantities.
A Micro Saddle Coil with Switchable Sensitivity for Local High-Resolution Imaging of Luminal Tissue
Tetsuji Dohi; Kousuke Murashige
2016-01-01
This paper reports on a micro saddle coil for local high-resolution magnetic resonance imaging (MRI) fabricated by embedding a flexible coil pattern into a polydimethyilsiloxane (PDMS) tube. We can change the sensitivity of the micro coil by deforming the shape of the coil from a saddle-shaped mode to a planar-shaped mode. The inductance, the resistance, and the Q-factor of the coil in the saddle-shaped mode were 2.45 μH, 3.31 Ω, and 39.9, respectively. Those of the planar-shaped mode were 3....
Polymer quantization and the saddle point approximation of partition functions
Técotl, Hugo A Morales; Rastgoo, Saeed
2015-01-01
The saddle point approximation of the path integral partition functions is an important way of deriving the thermodynamical properties of black holes. However, there are certain black hole models and some mathematically analog mechanical models for which this method can not be applied directly. This is due to the fact that their action evaluated on a classical solution is not finite and its first variation does not vanish for all consistent boundary conditions. These problems can be dealt with by adding a counter-term to the classical action, which is a solution of the corresponding Hamilton-Jacobi equation. In this work we study the effects of polymer quantization on a mechanical model presenting the aforementioned difficulties and contrast it with the above counter-term method. This type of quantization for mechanical models is motivated by the loop quantization of gravity which is known to play a role in the thermodynamics of black holes systems. The model we consider is a non relativistic particle in an i...
A Three-level BDDC algorithm for saddle point problems
Energy Technology Data Exchange (ETDEWEB)
Tu, X.
2008-12-10
BDDC algorithms have previously been extended to the saddle point problems arising from mixed formulations of elliptic and incompressible Stokes problems. In these two-level BDDC algorithms, all iterates are required to be in a benign space, a subspace in which the preconditioned operators are positive definite. This requirement can lead to large coarse problems, which have to be generated and factored by a direct solver at the beginning of the computation and they can ultimately become a bottleneck. An additional level is introduced in this paper to solve the coarse problem approximately and to remove this difficulty. This three-level BDDC algorithm keeps all iterates in the benign space and the conjugate gradient methods can therefore be used to accelerate the convergence. This work is an extension of the three-level BDDC methods for standard finite element discretization of elliptic problems and the same rate of convergence is obtained for the mixed formulation of the same problems. Estimate of the condition number for this three-level BDDC methods is provided and numerical experiments are discussed.
Two-Dimensional Saddle Point Equation of Ginzburg-Landau Hamiltonian for the Diluted Ising Model
Institute of Scientific and Technical Information of China (English)
WU Xin-Tian
2006-01-01
@@ The saddle point equation of Ginzburg-Landau Hamiltonian for the diluted Ising model is developed. The ground state is solved numerically in two dimensions. The result is partly explained by the coarse-grained approximation.
Saiki, Yoshitaka; Yamada, Michio; Chian, Abraham C-L; Miranda, Rodrigo A; Rempel, Erico L
2015-10-01
The unstable periodic orbits (UPOs) embedded in a chaotic attractor after an attractor merging crisis (MC) are classified into three subsets, and employed to reconstruct chaotic saddles in the Kuramoto-Sivashinsky equation. It is shown that in the post-MC regime, the two chaotic saddles evolved from the two coexisting chaotic attractors before crisis can be reconstructed from the UPOs embedded in the pre-MC chaotic attractors. The reconstruction also involves the detection of the mediating UPO responsible for the crisis, and the UPOs created after crisis that fill the gap regions of the chaotic saddles. We show that the gap UPOs originate from saddle-node, period-doubling, and pitchfork bifurcations inside the periodic windows in the post-MC chaotic region of the bifurcation diagram. The chaotic attractor in the post-MC regime is found to be the closure of gap UPOs.
U.S. Geological Survey, Department of the Interior — The smthk_f grid represents the modeled combined thickness of the Saddle Mountains Basalt and Mabton interbed geomodel units at a 500 foot resolution. It is one grid...
Energy Technology Data Exchange (ETDEWEB)
Saiki, Yoshitaka, E-mail: yoshi.saiki@r.hit-u.ac.jp [Graduate School of Commerce and Management, Hitotsubashi University, Tokyo 186-8601 (Japan); Yamada, Michio [Research Institute for Mathematical Sciences (RIMS), Kyoto University, Kyoto 606-8502 (Japan); Chian, Abraham C.-L. [Paris Observatory, LESIA, CNRS, 92195 Meudon (France); National Institute for Space Research (INPE), P.O. Box 515, São José dos Campos, São Paulo 12227-010 (Brazil); Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), São José dos Campos, São Paulo 12228-900 (Brazil); School of Mathematical Sciences, University of Adelaide, Adelaide SA 5005 (Australia); Department of Biomedical Engineering, George Washington University, Washington, DC 20052 (United States); Miranda, Rodrigo A. [Faculty UnB-Gama, and Plasma Physics Laboratory, Institute of Physics, University of Brasília (UnB), Brasília DF 70910-900 (Brazil); Rempel, Erico L. [Institute of Aeronautical Technology (ITA) and World Institute for Space Environment Research (WISER), São José dos Campos, São Paulo 12228-900 (Brazil)
2015-10-15
The unstable periodic orbits (UPOs) embedded in a chaotic attractor after an attractor merging crisis (MC) are classified into three subsets, and employed to reconstruct chaotic saddles in the Kuramoto-Sivashinsky equation. It is shown that in the post-MC regime, the two chaotic saddles evolved from the two coexisting chaotic attractors before crisis can be reconstructed from the UPOs embedded in the pre-MC chaotic attractors. The reconstruction also involves the detection of the mediating UPO responsible for the crisis, and the UPOs created after crisis that fill the gap regions of the chaotic saddles. We show that the gap UPOs originate from saddle-node, period-doubling, and pitchfork bifurcations inside the periodic windows in the post-MC chaotic region of the bifurcation diagram. The chaotic attractor in the post-MC regime is found to be the closure of gap UPOs.
Saddle-Shaped Annuloplasty Improves Leaflet Coaptation in Repair for Ischemic Mitral Regurgitation
Bouma, Wobbe; Aoki, Chikashi; Vergnat, Mathieu; Pouch, Alison M.; Sprinkle, Shanna R.; Gillespie, Matthew J.; Mariani, Massimo A.; Jackson, Benjamin M.; Gorman, Robert C.; Gorman, Joseph H.
2015-01-01
Background. Current repair results for ischemic mitral regurgitation (IMR) with undersized annuloplasty rings are characterized by high IMR recurrence rates. Current annuloplasty rings treat annular dilatation, but they do little to improve (and may actually exacerbate) leaflet tethering. New saddle
General scaling law in the saddle-node bifurcation: a complex phase space study
Energy Technology Data Exchange (ETDEWEB)
Fontich, Ernest [Departament de Matematica Aplicada i Analisi, Universitat de Barcelona, Gran Via de les Corts Catalanes 585, 08007 Barcelona (Spain); Sardanyes, Josep [Complex Systems Lab (ICREA-UPF), Barcelona Biomedical Research Park (PRBB-GRIB), Dr Aiguader 88, 08003 Barcelona (Spain)
2008-01-11
Saddle-node bifurcations have been described in a multitude of nonlinear dynamical systems modeling physical, chemical, as well as biological systems. Typically, this type of bifurcation involves the transition of a given set of fixed points from the real to the complex phase space. After the bifurcation, a saddle remnant can continue influencing the flows and generically, for non-degenerate saddle-node bifurcations, the time the flows spend in the bottleneck region of the ghost follows the inverse square root scaling law. Here we analytically derive this scaling law for a general one-dimensional, analytical, autonomous dynamical system undergoing a not necessarily non-degenerate saddle-node bifurcation, in terms of the degree of degeneracy by using complex variable techniques. We then compare the analytic calculations with a one-dimensional equation modeling the dynamics of an autocatalytic replicator. The numerical results are in agreement with the analytical solution.
Importance of static adjustment of knee angle to determine saddle height in cycling
Priego Quesada, Jose Ignacio; Jacques, Tiago Canal; R Bini, Rodrigo; Felipe P. Carpes
2016-01-01
Knee flexion angle is used to determine saddle height during pedaling. However, it is unclear if knee flexion angle at upright standing posture affects measures and interpretation of knee flexion angle during cycling. The objective of this study was to assess the importance of adjusting knee angle during pedaling according to the knee angle at upright posture. Seventeen cyclists performed three 10 min cycling trials at different saddle heights to induce knee flexion angles (40º, 30º or 20º wh...
Kinematic Geometry for the Saddle Line Fitting of Planar Discrete Positions
Institute of Scientific and Technical Information of China (English)
WU Yu; WANG Delun; WANG Wei; YU Shudong; XU Wenji
2015-01-01
The position synthesis of planar linkages is to locate the center point of the moving joint on a rigid link, whose trajectory is a circle or a straight line. Utilizing the min-max optimization scheme, the fitting curve needs to minimize the maximum fitting error to acquire the dimension of a planar binary P-R link. Based on the saddle point programming, the fitting straight line is determined to the planar discrete point-path traced by the point of the rigid body in planar motion. The property and evolution of the defined saddle line error can be revealed from three given separate points. A quartic algebraic equation relating the fitting error and the coordinates is derived, which agrees with the classical theory. The effect of the fourth point is discussed in three cases through the constraint equations. The multi-position saddle line error is obtained by combination and comparison from the saddle point programming. Several examples are presented to illustrate the solution process for the saddle line error of the moving plane. The saddle line error surface and the contour map presented to show the variations of the fitting error in the fixed frame. The discrete kinematic geometry is then set up to disclose the relations of the separate positions of the rigid body, the location of the tracing point on the moving body, and the position and orientation of the saddle line to the point-path. This paper presents a new analytic geometry method for saddle line fitting and provides a theoretical foundation for position synthesis.
Kinematic geometry for the saddle line fitting of planar discrete positions
Wu, Yu; Wang, Delun; Wang, Wei; Yu, Shudong; Xu, Wenji
2015-07-01
The position synthesis of planar linkages is to locate the center point of the moving joint on a rigid link, whose trajectory is a circle or a straight line. Utilizing the min-max optimization scheme, the fitting curve needs to minimize the maximum fitting error to acquire the dimension of a planar binary P-R link. Based on the saddle point programming, the fitting straight line is determined to the planar discrete point-path traced by the point of the rigid body in planar motion. The property and evolution of the defined saddle line error can be revealed from three given separate points. A quartic algebraic equation relating the fitting error and the coordinates is derived, which agrees with the classical theory. The effect of the fourth point is discussed in three cases through the constraint equations. The multi-position saddle line error is obtained by combination and comparison from the saddle point programming. Several examples are presented to illustrate the solution process for the saddle line error of the moving plane. The saddle line error surface and the contour map presented to show the variations of the fitting error in the fixed frame. The discrete kinematic geometry is then set up to disclose the relations of the separate positions of the rigid body, the location of the tracing point on the moving body, and the position and orientation of the saddle line to the point-path. This paper presents a new analytic geometry method for saddle line fitting and provides a theoretical foundation for position synthesis.
Cocq, de P.; Weeren, van P.R.; Back, W.
2006-01-01
Saddle-fit is recognised as an important factor in the pathogenesis of back problems in horses and is empirically being evaluated by pressure measurements in clinical practice, although not much is known about the validity, reliability and usability of these devices in the equine field. This study w
Directory of Open Access Journals (Sweden)
Conrado VILANOU TORRANO
2010-03-01
Full Text Available RESUMEN: En este trabajo se reproduce y comenta un informe remitido por Juan Roura-Parella, discípulo predilecto de Joaquín Xirau, desde Berlín en febrero de 1932. Frente a la atracción ejercida en España por el positivismo, Roura-Parella —que estudió Pedagogía en Alemania durante dos años (1930-1932— plantea la alternativa de la pedagogía de las ciencias del espíritu (Geisteswissenschaftliche Pädagogik que, siguiendo la huella de Dilthey, defendía Spranger en sintonía con la escuela del trabajo (Arbeitsbildung de Kerschensteiner. De alguna manera, esta pedagogía que combinaba la especialización profesional y los valores objetivos de la cultura deseaba vivificar —de acuerdo con la tradición formativa del idealismo de la libertad (Kant, Schiller, Goethe— una cultura que, después de la Primera Guerra Mundial, había entrado en una profunda crisis económica, política, social y, sobre todo, espiritual, situación que no era extraña en aquella incipiente España de la Segunda República (1931-1939. ABSTRACT: This work includes a reproduction of and comment on a report sent from Berlin by Juan Roura-Parella, favourite disciple of Joaquín Xirau, in February 1932. Faced with the appeal of positivism, Roura-Parella —who studied Pedagogy in Germany for two years (1930-1932— put forward the alternative of spiritual scientific pedagogy (Geisteswissenschaftliche Pädagogik which, in the footsteps of Dilthey, defended Spranger and befitted Kerschensteiner’s work school (Arbeitsbildung. Somehow, this pedagogy, which combined professional specialisation and the objective values of culture, aimed at revitalising —in accordance with the educational tradition of the idealism of freedom (Kant, Schiller, Goethe—, a culture that had entered a profound economic, political, social and, most particularly, spiritual crisis after the First World War, a situation that was not unfamiliar in the incipient Spain of the Second Republic
A Micro Saddle Coil with Switchable Sensitivity for Local High-Resolution Imaging of Luminal Tissue
Directory of Open Access Journals (Sweden)
Tetsuji Dohi
2016-04-01
Full Text Available This paper reports on a micro saddle coil for local high-resolution magnetic resonance imaging (MRI fabricated by embedding a flexible coil pattern into a polydimethyilsiloxane (PDMS tube. We can change the sensitivity of the micro coil by deforming the shape of the coil from a saddle-shaped mode to a planar-shaped mode. The inductance, the resistance, and the Q-factor of the coil in the saddle-shaped mode were 2.45 μH, 3.31 Ω, and 39.9, respectively. Those of the planar-shaped mode were 3.07 μH, 3.92 Ω, and 42.9, respectively. In MRI acquired in saddle-shaped mode, a large visible area existed around the coil. Although the sensitive area was considerably reduced in the planar-shaped mode, clear MRI images were obtained. The signal-to-noise ratios (SNR of the saddle-shaped and planar-shaped modes were 194.9 and 505.9, respectively, at voxel size of 2.0 × 2.0 × 2.0 mm3 and 11.7 and 37.4, respectively, at voxel size of 0.5 × 0.5 × 1.0 mm3. The sensitivity of the saddle-shaped and the planar-shaped modes were about 3 times and 10 times higher, respectively, than those of the medical head coil at both voxel sizes. Thus, the micro saddle coil enabled large-area imaging and highly sensitive imaging by switching the shape of the coil.
Mauguière, F. A. L.; Collins, P.; Ezra, G. S.; Wiggins, S.
2013-04-01
We investigate the fragmentation dynamics of an atomic chain under tensile stress. We have classified the location, stability type (indices), and energy of all equilibria for the general n-particle chain, and have highlighted the importance of saddle points with index >1. We show that for an n = 2-particle chain under tensile stress the index 2 saddle plays a central role in organizing the dynamics. We apply normal form theory to analyze phase space structure and dynamics in a neighborhood of the index 2 saddle. We define a phase dividing surface (DS) that enables us to classify trajectories passing through a neighborhood of the saddle point using the values of the integrals associated with the normal form. We also generalize our definition of the dividing surface and define an extended dividing surface (EDS), which is used to sample and classify all trajectories that pass through a phase space neighborhood of the index 2 saddle at total energies less than that of the saddle. Classical trajectory simulations are used to study fragmentation patterns for the n = 2 chain under tension. That is, we investigate the relative probability for breaking one bond versus concerted fission of several (two, in this case) bonds. Initial conditions for trajectories are obtained by sampling the EDS at constant energy. We sample trajectories at fixed energies both above and below the energy of the saddle. The fate of trajectories (single versus multiple bond breakage) is explored as a function of the location of the initial condition on the EDS, and a connection made to the work of Chesnavich on collision-induced dissociation. A significant finding is that we can readily identify trajectories that exhibit bond healing. Such trajectories pass outside the nominal (index 1) transition state for single bond dissociation, but return to the potential well region, possibly several times, before ultimately dissociating.
Yang, Jianke
2012-03-01
Saddle-node bifurcations arise frequently in solitary waves of diverse physical systems. Previously it was believed that solitary waves always undergo stability switching at saddle-node bifurcations, just as in finite-dimensional dynamical systems. Here we show that this is not true. For a large class of generalized nonlinear Schrödinger equations with real or complex potentials, we prove that stability of solitary waves does not switch at saddle-node bifurcations. This analytical result is confirmed by numerical examples where both soliton branches are stable at saddle-node bifurcations.
Ferrer-Roca, Ventura; Roig, Andreu; Galilea, Piero; García-López, Juan
2012-11-01
In cycling, proper saddle height is important because it contributes to the mechanical work of the lower limb joints, thus altering pedaling efficiency. The appropriate method to select optimal saddle height is still unknown. This study was conducted to compare a static (anthropometric measurements) vs. a dynamic method (2D analysis) to adjust saddle height. Therefore, an examination of the relationship between saddle height, anthropometrics, pedaling angles, and hamstring flexibility was carried out. Saddle height outside of the recommended range (106-109% of inseam length) was observed in 56.5% of the subjects. Inappropriate knee flexion angles using the dynamic method were observed in 26% of subjects. The results of this study support the concept that adjusting saddle height to 106-109% of inseam length may not ensure an optimal knee flexion (30-40°). To solve these discrepancies, we applied a multiple linear regression to study the relationship between anthropometrics, pedaling angles, and saddle height. The results support the contention that saddle height, inseam length, and knee angle are highly related (R = 0.963, p < 0.001). We propose a novel equation that relates these factors to recommend an optimal saddle height (108.6-110.4% of inseam length).
Why do galactic spins flip in the cosmic web? A Theory of Tidal Torques near saddles
Pichon, Christophe; Pogosyan, Dmitry; Dubois, Yohan; Desjacques, Vincent; Devriendt, Julien
2014-01-01
Filaments of the cosmic web drive spin acquisition of disc galaxies. The point process of filament-type saddle represent best this environment and can be used to revisit the Tidal Torque Theory in the context of an anisotropic peak (saddle) background split. The constrained misalignment between the tidal tensor and the Hessian of the density field generated in the vicinity of filament saddle points simply explains the corresponding transverse and longitudinal point-reflection symmetric geometry of spin distribution. It predicts in particular an azimuthal orientation of the spins of more massive galaxies and spin alignment with the filament for less massive galaxies. Its scale dependence also allows us to relate the transition mass corresponding to the alignment of dark matter halos spin relative to the direction of their neighboring filament to this geometry, and to predict accordingly it s scaling with the mass of non linearity, as was measured in simulations.
Symbolic Dynamics and Spiral Structures due to the Saddle-Focus Bifurcations
Shilnikov, Andrey; Shilnikov, Leonid; Barrio, Roberto
2013-01-01
We examine spiral structures in bi-parametric diagrams of dissipative systems with strange attractors. We show that the organizing center for spiral structures in the Rössler model with the saddle-focus equilibria is related to the change of the structure of the attractor transitioning between the spiral and screw-like types. The structure skeleton is formed by saddlenode bifurcation curves originating from a codimension-two Belyakov point corresponding to the transition to the saddle-focus from a simple saddle. A new computational technique based on the symbolic kneading invariant description for examining dynamical chaos and parametric chaos in systems with Lorenz-like attractors is proposed and tested. This technique uncovers the stunning complexity and universality of spiral structures in the iconic Lorenz equations.
HESSIAN MATRIX BASED SADDLE POINT DETECTION FOR GRANULES SEGMENTALTION IN 2D IMAGE
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
Segmenting the touching objects in an image has been remaining as a hot subject due to the problematic complexities,and a vast number of algorithms designed to tackle this issue have come into being since a decade ago.In this paper,a new granule segmentation algorithm is developed using saddle point as the cutting point.The image is binarized and then sequentially eroded to form a gray-scale topographic counterpart,followed by using Hessian matrix computation to search for the saddle point. The segmentation is performed by cutting through the saddle point and along the maximal gradient path on the topographic surface.The results of the algorithm test on the given real images indicate certain superiorities in both the segmenting robustness and execution time to the referenced methods.
Why do galactic spins flip in the cosmic web? A Theory of Tidal Torques near saddles
Pichon, Christophe; Codis, Sandrine; Pogosyan, Dmitry; Dubois, Yohan; Desjacques, Vincent; Devriendt, Julien
2016-10-01
Filaments of the cosmic web drive spin acquisition of disc galaxies. The point process of filament-type saddle represent best this environment and can be used to revisit the Tidal Torque Theory in the context of an anisotropic peak (saddle) background split. The constrained misalignment between the tidal tensor and the Hessian of the density field generated in the vicinity of filament saddle points simply explains the corresponding transverse and longitudinal point-reflection symmetric geometry of spin distribution. It predicts in particular an azimuthal orientation of the spins of more massive galaxies and spin alignment with the filament for less massive galaxies. Its scale dependence also allows us to relate the transition mass corresponding to the alignment of dark matter halos' spin relative to the direction of their neighboring filament to this geometry, and to predict accordingly it's scaling with the mass of non linearity, as was measured in simulations.
Complex saddle points and the sign problem in complex Langevin simulation
Hayata, Tomoya; Tanizaki, Yuya
2015-01-01
We show that complex Langevin simulation converges to a wrong result, by relating it to the Lefschetz-thimble path integral, when the path-integral weight has different phases among dominant complex saddle points. Equilibrium solution of the complex Langevin equation forms local distributions around complex saddle points. Its ensemble average approximately becomes a direct sum of the average in each local distribution, where relative phases among them are dropped. We propose that by taking these phases into account through reweighting, we can solve the wrong convergence problem. However, this prescription may lead to a recurrence of the sign problem in the complex Langevin method for quantum many-body systems.
Study for reasonable value of friction coefficient between main cable and saddle
Institute of Scientific and Technical Information of China (English)
Deng Ting; Luo Xiheng
2012-01-01
The value of friction coefficient between the main cable and saddle, relates to not only the anti-slippage stability of three-tower suspension bridge, but also the reasonable stiffness of the middle tower and the magnitude of rigidity of the whole bridge. First, the paper does some comparative studies about the relevant provisions of international norms, and then, summarizes the relevant load test results both at home and abroad. Finally, the paper draws the appropriate anti-slippage safety factor for the most unfavorable load in accordance with international load standards, and discusses the rationality and feasibility of the friction coefficient of 0.2 between main cable and saddle.
Non-smooth saddle-node bifurcations III: Strange attractors in continuous time
Fuhrmann, G.
2016-08-01
Non-smooth saddle-node bifurcations give rise to minimal sets of interesting geometry built of so-called strange non-chaotic attractors. We show that certain families of quasiperiodically driven logistic differential equations undergo a non-smooth bifurcation. By a previous result on the occurrence of non-smooth bifurcations in forced discrete time dynamical systems, this yields that within the class of families of quasiperiodically driven differential equations, non-smooth saddle-node bifurcations occur in a set with non-empty C2-interior.
Effect of Saddle-Splay Elasticity on Stability of Disclination Rings in Nematic Liquid Crystals
Institute of Scientific and Technical Information of China (English)
WANG Yu-Sheng; YUAN Bao-He; YANG Guo-Hong
2008-01-01
In this paper, the stability of disclination ring in nematic liquid crystals is studied. In the presence of saddle-splay elasticity (characterized by k24) the disclination ring has a universal equilibrium radius. Depending on the values of the saddle-splay constant k24, the universal equilibrium radius is altered. When k24 > 0.92k (m=1/2) and k24>0.88k (m = -1/2), the disclination will be a point rather than a ring, where k is the Frank elastic constant in the one-constant approximation.
CONTROL OF A SADDLE NODE BIFURCATION IN A POWER SYSTEM USING A PID CONTROLLER
Directory of Open Access Journals (Sweden)
J. Alvarez
2003-04-01
Full Text Available In this work, we present the elimination of a saddle-node bifurcation in a basic power system using a PIDcontroller. In addition, a stability analysis of the rotor angle and its frequency, which are directly related tovoltage collapse problem, is presented.
Existence Theorems of ε-Cone Saddle Points for Vector-Valued Mappings
Directory of Open Access Journals (Sweden)
Tao Chen
2014-01-01
Full Text Available A new existence result of ε-vector equilibrium problem is first obtained. Then, by using the existence theorem of ε-vector equilibrium problem, a weakly ε-cone saddle point theorem is also obtained for vector-valued mappings.
Coincidence Point Theorems, Intersection Theorems and Saddle Point Theorems on FC-spaces
Institute of Scientific and Technical Information of China (English)
PIAO YONG-JIE; YIN ZHE
2009-01-01
In this paper, we first give the definitions of finitely continuous topological space and FC-subspace generated by some set, and obtain coincidence point theorem, whole intersection theorems and Ky Fan type matching theorems, and finally discuss the existence of saddle point as an application of coincidence point theorem.
76 FR 56318 - Parts and Accessories Necessary for Safe Operation; Saddle-Mount Braking Requirements
2011-09-13
... supporting tests sponsored by ATC Leasing Company (ATC) \\2\\ in 2003. RAI tested a total of 24 triple saddle... this document. \\1\\ Radlinksi & Associates is now known as Link-Radlinksi, Inc. \\2\\ ATC Leasing Company... the aggregate, or by the private sector, of $141.3 million (which is the value of $100 million in...
Exact propagator for an electron in a quadratic saddle-point potential and a magnetic field
Institute of Scientific and Technical Information of China (English)
Yang Tao; Zhai Zhi-Yuan; Pan Xiao-Yin
2011-01-01
We study the propagator for an electron moving in a two-dimensional(2D)quadratic saddle-point potential, in the presence of a perpendicular uniform magnetic field. A closed-form expression for the propagator is derived using the Feynmann path integrals.
Modeled Top of the Saddle Mountains Basalt Geomodel Unit (smtop_f)
U.S. Geological Survey, Department of the Interior — The smtop_f grid represents the modeled elevation of the top of the Saddle Mountains Basalt geomodlel unit at a 500 foot resolution. It is one grid of a geomodel...
Venkat Ramana, M.; Chorghe, A.; Venu, P.
2014-01-01
Two new species of Syzygium, S. hookeri and S. sanjappaiana from the Saddle Peak National Park of North Andaman Islands, are described and illustrated. The novelties are deliberated in the light of reviewed concept on the genus Syzygium and discussed with related species of Myanmar and Sri Lanka.
Travelling waves associated with saddle-node bifurcation in weakly coupled CML
Energy Technology Data Exchange (ETDEWEB)
Sotelo Herrera, Ma Dolores, E-mail: dsh@dfmf.uned.e [Departamento de Matematica Aplicada, E.U.I.T.I., Universidad Politecnica de Madrid, Ronda de Valencia 3, 28012 Madrid (Spain); San Martin, Jesus, E-mail: jsm@dfmf.uned.e [Departamento de Matematica Aplicada, E.U.I.T.I., Universidad Politecnica de Madrid, Ronda de Valencia 3, 28012 Madrid (Spain); Departamento de Fisica Matematica y de Fluidos, U.N.E.D., Senda del Rey 9, 28040 Madrid (Spain)
2010-07-19
Weakly coupled CML can be analytically solved by using perturbative methods. This technique has been recently used to deduce analytical expressions for travelling waves. Nonetheless, the results were limited for periodic solutions far away from saddle-node bifurcation. In this Letter, this problem is solved and periodic solutions, arising from the individual dynamics, are totally characterised.
Differential diagnosis in cases of saddle-like impression of the fundus of the stomach
Energy Technology Data Exchange (ETDEWEB)
Hohenberg, G.; Deimer, E.; Schmidmeier, L.
1984-01-01
X-ray examination of the stomach sometimes shows a saddle-like impression of the region of the fundus. This phenomenon is without any clinical importance, but there are many diseases such as hiatal hernia, benign and malignant tumours, inflammatory diseases, and varices which are localised at the fundus. Differential diagnostic problems are discussed.
LEAST-SQUARES MIXED FINITE ELEMENT METHOD FOR SADDLE-POINT PROBLEM
Institute of Scientific and Technical Information of China (English)
Lie-heng Wang; Huo-yuan Duan
2000-01-01
In this paper, a least-squares mixed finite element method for the solution of the primal saddle-point problem is developed. It is proved that the approximate problem is consistent ellipticity in the conforming finite element spaces with only the discrete BB-condition needed for a smaller auxiliary problem. The abstract error estimate is derived.
Drótos, G.; Jung, C.
2016-06-01
The topic of this paper is hyperbolic chaotic scattering in a three degrees of freedom system. We generalize how shadows in the domain of the doubly differential cross-section are found: they are traced out by the appropriately filtered unstable manifolds of the periodic trajectories in the chaotic saddle. These shadows are related to the rainbow singularities in the doubly differential cross-section. As a result of this relation, we discover a method of how to recognize in the cross section a smoothly deformed image of the chaotic saddle, allowing the reconstruction of the symbolic dynamics of the chaotic saddle, its topology and its scaling factors.
Complex saddle points and the sign problem in complex Langevin simulation
Hayata, Tomoya; Hidaka, Yoshimasa; Tanizaki, Yuya
2016-10-01
We show that complex Langevin simulation converges to a wrong result within the semiclassical analysis, by relating it to the Lefschetz-thimble path integral, when the path-integral weight has different phases among dominant complex saddle points. Equilibrium solution of the complex Langevin equation forms local distributions around complex saddle points. Its ensemble average approximately becomes a direct sum of the average in each local distribution, where relative phases among them are dropped. We propose that by taking these phases into account through reweighting, we can solve the wrong convergence problem. However, this prescription may lead to a recurrence of the sign problem in the complex Langevin method for quantum many-body systems.
Saddle-shaped reticulate Nummulites from Early Oligocene rocks of Khari area, SW Kutch, India
Indian Academy of Sciences (India)
S Sengupta; Sampa Sarkar; S Mukhopadhyay
2011-04-01
Saddle-shaped reticulate Nummulites from the Early Oligocene rocks of Khari area, SW Kutch, India is reported here for the first time. Unusual shape of this Nummulites is due to the curved nature of the coiling plane, indicating space constrained postembryonic test growth. With regular development of chambers, septa and septal filaments, the saddle-shaped Nummulites constitutes the third morphotype of N. cf. fichteli Michelotti form A. Other morphotypes of the species reported earlier include inflated lenticular and conical tests. Multiple morphotypes of N. cf. fichteli form A indicates varied test growth in response to substrate conditions. Morphological variability exhibited by N. cf. fichteli form A from Kutch and some Early Oligocene reticulate Nummulites from the Far East are comparable. This faunal suite is morphologically distinct from the contemporary reticulate Nummulites of the European localities.
Homoclinic bifurcations that give rise to heterodimensional cycles near a saddle-focus equilibrium
Li, Dongchen
2017-01-01
We show that heterodimensional cycles can be born at the bifurcations of a pair of homoclinic loops to a saddle-focus equilibrium for flows in dimension 4 and higher. In addition to the classical heterodimensional connection between two periodic orbits, we found, in intermediate steps, two new types of heterodimensional connections: one is a heteroclinic between a homoclinic loop and a periodic orbit with a 2-dimensional unstable manifold, and the other connects a saddle-focus equilibrium to a periodic orbit with a 3-dimensional unstable manifold. This work was supported by grant RSF 14-41-00044 at Lobachevsky University of Nizhny Novgorod. The author also acknowledges support by the Royal Society grant IE141468 and EU Marie-Curie IRSES Brazilian-European partnership in Dynamical Systems (FP7-PEOPLE-2012-IRSES 318999 BREUDS).
The saddle-node-transcritical bifurcation in a population model with constant rate harvesting
Saputra, K V I; Quispel, G R W
2010-01-01
We study the interaction of saddle-node and transcritical bifurcations in a Lotka-Volterra model with a constant term representing harvesting or migration. Because some of the equilibria of the model lie on an invariant coordinate axis, both the saddle-node and the transcritical bifurcations are of codimension one. Their interaction can be associated with either a single or a double zero eigenvalue. We show that in the former case, the local bifurcation diagram is given by a nonversal unfolding of the cusp bifurcation whereas in the latter case it is a nonversal unfolding of a degenerate Bogdanov-Takens bifurcation. We present a simple model for each of the two cases to illustrate the possible unfoldings. We analyse the consequences of the generic phase portraits for the Lotka-Volterra system.
Complex saddle points and the sign problem in complex Langevin simulation
Directory of Open Access Journals (Sweden)
Tomoya Hayata
2016-10-01
Full Text Available We show that complex Langevin simulation converges to a wrong result within the semiclassical analysis, by relating it to the Lefschetz-thimble path integral, when the path-integral weight has different phases among dominant complex saddle points. Equilibrium solution of the complex Langevin equation forms local distributions around complex saddle points. Its ensemble average approximately becomes a direct sum of the average in each local distribution, where relative phases among them are dropped. We propose that by taking these phases into account through reweighting, we can solve the wrong convergence problem. However, this prescription may lead to a recurrence of the sign problem in the complex Langevin method for quantum many-body systems.
Toward Picard-Lefschetz Theory of Path Integrals, Complex Saddles and Resurgence
Behtash, Alireza; Schaefer, Thomas; Sulejmanpasic, Tin; Unsal, Mithat
2015-01-01
We show that the semi-classical analysis of generic Euclidean path integrals necessarily requires complexification of the action and measure, and consideration of complex saddle solutions. We demonstrate that complex saddle points have a natural interpretation in terms of the Picard-Lefschetz theory. Motivated in part by the semi-classical expansion of QCD with adjoint matter on ${\\mathbb R}^3\\times S^1$, we study quantum-mechanical systems with bosonic and fermionic (Grassmann) degrees of freedom with harmonic degenerate minima, as well as (related) purely bosonic systems with harmonic non-degenerate minima. We find exact finite action non-BPS bounce and bion solutions to the holomorphic Newton equations. We find not only real solutions, but also complex solution with non-trivial monodromy, and finally complex multi-valued and singular solutions. Complex bions are necessary for obtaining the correct non-perturbative structure of these models. In the supersymmetric limit the complex solutions govern the groun...
Chen, Junting
2011-01-01
Saddle point problems arise from many wireless applications, and primal-dual iterative algorithms are widely applied to find the saddle points. In the existing literature, the convergence results of such algorithms are established assuming the problem specific parameters remain unchanged during the iterations. However, this assumption is unrealistic in time varying wireless systems, as explicit message passing is usually involved in the iterations and the channel state information (CSI) may change in a time scale comparable to the algorithm update period. This paper investigates the convergence behavior and the tracking error of primal-dual iterative algorithms under time varying CSI. The convergence results are established by studying the stability of an equivalent virtual dynamic system derived in the paper, and the Lyapunov theory is applied for the stability analysis. We show that the average tracking error is proportional to the time variation rate of the CSI. Based on these analyses, we also derive an a...
Det-Det correlations for quantum maps: Dual pair and saddle-point analyses
Nonnenmacher, S.; Zirnbauer, M. R.
2002-05-01
An attempt is made to clarify the ballistic nonlinear sigma model formalism recently proposed for quantum chaotic systems, by looking at the spectral determinant Z(s)=Det(1-sU) for quantized maps U∈U(N), and studying the correlator ωU(s)=∫dθ|Z(eiθs)|2. By identifying U(N) as one member of a dual pair acting in the spinor representation of Spin(4N), the expansion of ωU(s) in powers of s2 is shown to be a decomposition into irreducible characters of U(N). In close analogy with the ballistic nonlinear sigma model, a coherent-state integral representation of ωU(s) is developed. For generic U this integral has (N2N) saddle points and the leading-order saddle-point approximation turns out to reproduce ωU(s) exactly, up to a constant factor. This miracle is explained by interpreting ωU(s) as a character of U(2N), and arguing that the leading-order saddle-point result corresponds to the Weyl character formula. Unfortunately, the Weyl decomposition behaves nonsmoothly in the semiclassical limit N→∞, and to make further progress some additional averaging needs to be introduced. Several schemes are investigated, including averaging over basis states and an "isotropic" average. The saddle-point approximation applied in conjunction with these schemes is demonstrated to give incorrect results in general, one notable exception being a semiclassical averaging scheme, for which all loop corrections vanish identically. As a side product of the dual pair decomposition with isotropic averaging, the crossover between the Poisson and CUE limits is obtained.
NMS Flows on Three-Dimensional Manifolds with One Saddle Periodic Orbit
Institute of Scientific and Technical Information of China (English)
B. CAMPOS; A. CORDERO; J. Mart(i)nez ALFARO; P. VINDEL
2004-01-01
The simplest NMS flow is a polar flow formed by an attractive periodic orbit and a repulsive periodic orbit as limit sets. In this paper we show that the only orientable, simple, compact,3-dimensional manifolds without boundary that admit an NMS flow with none or one saddle periodic orbit are lens spaces.We also see that when a fattened round handle is a connected sum of tori, the corresponding flow is also a trivial connected sum of flows.
Hennessey, Adam; Setyono, Devy A; Lau, Wayne Bond; Fields, Jason Matthew
2012-06-01
We report a patient with chest pain who was classified as having low risk for pulmonary embolism with clinical gestalt and accepted clinical decision rules. An inadvertently ordered D-dimer and abnormal result, however, led to the identification of a large saddle embolus. This case illustrates the fallibility of even well-validated decision aids and that an embolism missed by these tools is not necessarily low risk or indicative of a low clot burden.
Space Maintenance and New Bone Formation with Polyurethane Biocomposites in a Canine Saddle Defect
2014-05-01
osteoblast differentiation, and enhance new bone formation. Biodegradable polyurethane ( PUR ) biocomposites containing allograft bone particles are...used effectively in a variety of bone regeneration applications.4 In the present study, we investigated the ability of injectable PUR /MG and PUR /BG...The lyophilized rhBMP-2 was hand-mixed with the PUR and injected into saddle defects (4/animal) measuring approximately 7-8 mm apicocoronal by 8-10
Steady f-plane circulation in basins with saddle-point bathymetry
Jenkins, A D
2005-01-01
J. Nilsson, G. Walin, and G. Brostroem (paper accepted by Journal of Marine Research, 2005) have recently shown how a velocity field in geostrophic and hydrostatic balance in an f-plane may be diagnosed from prescribed distributions of buoyancy and wind stress, in a basin with closed isobaths. I extend their analysis to cover basins with more complex depth contours, treating in particular the behaviour of the flow in the presence of a saddle point.
On the Late-Time Behavior of Virasoro Blocks and a Classification of Semiclassical Saddles
Fitzpatrick, A Liam
2016-01-01
Recent work has demonstrated that black hole thermodynamics and information loss/restoration in AdS$_3$/CFT$_2$ can be derived almost entirely from the behavior of the Virasoro conformal blocks at large central charge, with relatively little dependence on the precise details of the CFT spectrum or OPE coefficients. Here, we elaborate on the non-perturbative behavior of Virasoro blocks by classifying all `saddles' that can contribute for arbitrary values of external and internal operator dimensions in the semiclassical large central charge limit. The leading saddles, which determine the naive semiclassical behavior of the Virasoro blocks, all decay exponentially at late times, and at a rate that is independent of internal operator dimensions. Consequently, the semiclassical contribution of high-energy states does not resolve a well-known version of the information loss problem in AdS$_3$. However, we identify two infinite classes of sub-leading saddles, and one of these classes does not decay at late times.
Rotating saddle trap as Foucault's pendulum: a hidden 'Coriolis' force in an inertial frame
Kirillov, Oleg N
2016-01-01
According to Earnshaw's theorem an electrostatic potential cannot have stable equilibria, i.e. the minima, since such potentials are harmonic functions. However, the 1989 Nobel Prize in physics was awarded to W. Paul for his invention of the trap for suspending charged particles in an oscillating electric field. Paul's idea was to stabilize the saddle by "vibrating" the electrostatic field, by analogy with the so-called Stephenson-Kapitsa pendulum in which the upside-down equilibrium is stabilized by vibration of the pivot. Instead of vibration, the saddle can also be stabilized by rotation of the potential (in two dimensions); this has been known for nearly a century, since 1918. Particles confined in rotating saddle traps exhibit precession in the laboratory frame, which up to now has been explained by analyzing explicit solutions. Here we show that this precession is actually due to a hidden Coriolis-like force, which we uncover by a normal form transformation. Unlike the conventional Coriolis force, this ...
Mauguiere, F A L; Ezra, G S; Wiggins, S
2012-01-01
We investigate the fragmentation dynamics of an atomic chain under tensile stress. We have classified the location, stability type (indices) and energy of all equilibria for the general $n$-particle chain, and have highlighted the importance of saddle points with index $> 1$. We show that for an $n=2$-particle chain under tensile stress the index 2 saddle plays a central role in organizing the dynamics. We apply normal form theory to analyze phase space structure and dynamics in a neighborhood of the index 2 saddle. We define a phase dividing surface (DS) that enables us to classify trajectories passing through a neighborhood of the saddle point using the values of the integrals associated with the normal form. We also generalize our definition of the dividing surface and define an \\emph{extended dividing surface} (EDS), which is used to sample and classify all trajectories that pass through a phase space neighborhood of the index 2 saddle at total energies less than that of the saddle. Classical trajectory s...
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Fang Bao
2011-01-01
Full Text Available There exist two different types of equilibrium points in 3-D autonomous systems, named as saddle foci of index 1 and index 2, which are crucial for chaos generation. Although saddle foci of index 2 have been usually applied for creating double-scroll or double-wing chaotic attractors, saddle foci of index 1 are further considered for chaos generation in this paper. A novel approach for constructing chaotic systems is investigated by applying the switching control strategy and yielding a heteroclinic loop which connects two saddle foci of index 1. A basic 3-D linear system with an arbitrary normal direction of the eigenplane, possessing a saddle focus of index 1 whose corresponding eigenvalues satisfy the Shil'nikov inequality, is first introduced. Then a heteroclinic loop connecting two saddle foci of index 1 will be formed by applying the switching control strategy to the basic 3-D linear system. The heteroclinic loop consists of an unstable manifold, a stable manifold, and a heteroclinic point. Under the necessary conditions for forming the heteroclinic loop, the intended two-segmented piecewise linear system which exhibits the chaotic behavior in the sense of the Smale horseshoe can be finally constructed. An illustrative example is given, confirming the effectiveness of the proposed method.
LePain, D.L.; Lillis, P.G.; Helmold, K.P.; Stanley, R.G.
2012-01-01
Magoon and others (1980) described an 83-meter- (272-foot-) thick succession of Maastrichtian (Upper Cretaceous) conglomerate, sandstone, mudstone, and coal exposed on the south side of an unnamed drainage, approximately 3 kilometers (1.8 miles) east of Saddle Mountain in lower Cook Inlet (ﬁgs. 1 and 2). The initial signiﬁcance of this exposure was that it was the ﬁrst reported occurrence of nonmarine rocks of this age in outcrop in lower Cook Inlet, which helped constrain the Late Cretaceous paleogeography of the area and provided important information on the composition of latest Mesozoic sandstones in the basin. The Saddle Mountain section is thought to be an outcrop analog for Upper Cretaceous nonmarine strata penetrated in the OCS Y-0097 #1 (Raven) well, located approximately 40 kilometers (25 miles) to the south–southeast in Federal waters (ﬁg. 1). Atlantic Richﬁeld Company (ARCO) drilled the Raven well in 1980 and encountered oil-stained rocks and moveable liquid hydrocarbons between the depths of 1,760 and 3,700 feet. Completion reports on ﬁle with the Bureau of Ocean Energy Management (BOEM; formerly Bureau of Ocean Energy Management, Regulation and Enforcement, and prior to 2010, U.S. Minerals Management Service) either show ﬂow rates of zero or do not mention ﬂow rates. A ﬂuid analysis report on ﬁle with BOEM suggests that a wireline tool sampled some oil beneath a 2,010-foot diesel cushion during the ﬂ ow test of the 3,145–3,175 foot interval, but the recorded ﬂ ow rate was still zero (Kirk Sherwood, written commun., January 9, 2012). Further delineation and evaluation of the apparent accumulation was never performed and the well was plugged and abandoned. As part of a 5-year comprehensive evaluation of the geology and petroleum systems of the Cook Inlet forearc basin, the Alaska Division of Geological & Geophysical Surveys obtained a research permit from the National Park Service to access the relatively poorly understood ‘Saddle
Spike-adding in parabolic bursters: The role of folded-saddle canards
Desroches, Mathieu; Krupa, Martin; Rodrigues, Serafim
2016-09-01
The present work develops a new approach to studying parabolic bursting, and also proposes a novel four-dimensional canonical and polynomial-based parabolic burster. In addition to this new polynomial system, we also consider the conductance-based model of the Aplysia R15 neuron known as the Plant model, and a reduction of this prototypical biophysical parabolic burster to three variables, including one phase variable, namely the Baer-Rinzel-Carillo (BRC) phase model. Revisiting these models from the perspective of slow-fast dynamics reveals that the number of spikes per burst may vary upon parameter changes, however the spike-adding process occurs in an explosive fashion that involves special solutions called canards. This spike-adding canard explosion phenomenon is analysed by using tools from geometric singular perturbation theory in tandem with numerical bifurcation techniques. We find that the bifurcation structure persists across all considered systems, that is, spikes within the burst are incremented via the crossing of an excitability threshold given by a particular type of canard orbit, namely the true canard of a folded-saddle singularity. However there can be a difference in the spike-adding transitions in parameter space from one case to another, according to whether the process is continuous or discontinuous, which depends upon the geometry of the folded-saddle canard. Using these findings, we construct a new polynomial approximation of the Plant model, which retains all the key elements for parabolic bursting, including the spike-adding transitions mediated by folded-saddle canards. Finally, we briefly investigate the presence of spike-adding via canards in planar phase models of parabolic bursting, namely the theta model by Ermentrout and Kopell.
Approximate Dual Averaging Method for Multiagent Saddle-Point Problems with Stochastic Subgradients
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Deming Yuan
2014-01-01
Full Text Available This paper considers the problem of solving the saddle-point problem over a network, which consists of multiple interacting agents. The global objective function of the problem is a combination of local convex-concave functions, each of which is only available to one agent. Our main focus is on the case where the projection steps are calculated approximately and the subgradients are corrupted by some stochastic noises. We propose an approximate version of the standard dual averaging method and show that the standard convergence rate is preserved, provided that the projection errors decrease at some appropriate rate and the noises are zero-mean and have bounded variance.
Seyhan, Tamer
2010-10-01
Nasomaxillary depression, which may be seen with major saddle nose deformities, especially as a sequel to childhood nasal trauma, generally is overlooked during management of the saddle nose. To handle both the saddle nose deformity and nasomaxillary depression, the authors used a one-stage intraoral and external open rhinoplasty approach for 12 patients. Lateral nasal osteotomies and correction of midface retrusion with crescent-shaped autogenous rib cartilage grafts were performed through two bilateral intraoral gingivobuccal incisions. The external open rhinoplasty approach was used for the correction of the saddle nose deformities. The mean follow-up period after the surgery was 2 years (range, 1-3.5 years). The correction of nasal tip depression resulting from midface retrusion was evaluated by lateral cephalometric radiographs. The mean movement of the nasal tip anteriorly in the sagittal plane 1 year after the operation was 5.5 mm (range, 4-7 mm). The functional and aesthetic results were satisfactory for all the patients. As the findings show, the intraoral part of the approach provides a route for the placement of cartilage grafts to correct the depressed nasal tip, augment the paranasal area, and provide support to the lateral alar bases and the controlled low-to-low lateral osteotomies. The external part of the approach provides correction of the saddle nose deformity.
On the Saddle-point Solution and the Large-Coalition Behavior of Fingerprinting Games
Huang, Yen-Wei
2010-01-01
We study a fingerprinting game in which the number of colluders and the collusion channel are unknown. The encoder embeds fingerprints into a host sequence and provides the decoder with the capability to trace back pirated copies to the colluders. Fingerprinting capacity has recently been derived as the limit value of a sequence of maximin games with mutual information as their payoff functions. However, these games generally do not admit saddle-point solutions and are very hard to solve numerically. Here under the so-called Boneh-Shaw marking assumption, we reformulate the capacity as the value of a single two-person zero-sum game, and show that it is achieved by a saddle-point solution. If the maximal coalition size is k and the fingerprinting alphabet is binary, we show that capacity decays quadratically with k. Furthermore, we prove rigorously that the asymptotic capacity is 1/(k^2 2ln2) and we confirm our earlier conjecture that Tardos' choice of the arcsine distribution asymptotically maximizes the mutu...
Double incontinence as a first symptom of saddle embolism of the aorta leads to sudden paraplegia.
Sabzi, Feridoun; Faraji, Reza
2015-11-01
An aortic saddle embolus causing cauda equine syndrome followed by paraplegia is an exceedingly rare phenomenon in post-operative period in coronary artery bypass grafting. In non-CABG cases, reported documentation of neurological recovery from this event is even rarer. A 57-year-old male 8 days after uneventful OPCAP presented with severe lower extremity pain and sudden fecal and urinary incontinence, followed by the absence of pulsations in the lower limbs and paraplegia, during 20-minute period. He underwent immediate bilateral transfemoral embolectomy. The postoperative period was uneventful. The paraplegia recovered immediately after embolectomy and recovery from anesthesia. An angiography has been made to verify that a high origin of the great radicular artery above T12 level may be responsible for better recovery of paraplegia when its ostium obstructed by a saddle embolus relieved using embolectomy. Early surgical intervention in restoring the blood flow into the great radicular artery may prevent severe histological changes hitherto responsible for non-recovery from paraplegia in the earlier reports. Three unique characteristics of this article are as follows: 1) Occurrence of this complication in the post-operative period in off-pump CABG surgery; 2) Commencing of emboli with bizarre symptoms of double incontinence; 3) Combination of cauda equine syndrome and complete paralysis.
A randomized Mirror-Prox method for solving structured large-scale matrix saddle-point problems
Baes, Michel; Nemirovski, Arkadi
2011-01-01
In this paper, we derive a randomized version of the Mirror-Prox method for solving some structured matrix saddle-point problems, such as the maximal eigenvalue minimization problem. Deterministic first-order schemes, such as Nesterov's Smoothing Techniques or standard Mirror-Prox methods, require the exact computation of a matrix exponential at every iteration, limiting the size of the problems they can solve. Our method allows us to use stochastic approximations of matrix exponentials. We prove that our randomized scheme decreases significantly the complexity of its deterministic counterpart for large-scale matrix saddle-point problems. Numerical experiments illustrate and confirm our theoretical results.
Antony Beevor [þýðandi Jón Þ. Þór]: Fall Berlínar 1945. [Á frummálinu: Berlin the Downfall 1945.
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Arnar Þór Másson
2006-12-01
Full Text Available Ófáar bækur og bíómyndir hafa verið gerðar um síðari heimstyrjöldina. Flestar hafa fjallað um hlut bandamanna í styrjöldinni og hvernig þeim tókst að þrauka í gegnum árásir Þjóðverja, snúa taflinu sér í vil og ná að endingu fram "glæstum" sigri. Þegar hann var í höfn var réttað yfir óþokkunum og flestir fengu þeir makleg málagjöld. Fall Berlínar 1945 eftir sagnfræðinginn Anthony Beevor fjallar aftur á móti um allt annan raunveruleika, þ.e. um styrjöldina á austurvígstöðvunum, en þar bárust Þjóðverjar og Sovétmenn á banaspjótum. Án þess að lítið sé gert úr þjáningum þeirra sem tóku þátt í styrjöldinni eða voru fórnarlömb hennar á vesturvígstöðvunum voru átökin hvað grimmilegust á austurvígstöðvunum og mannfallið mest, bæði meðal óbreyttra borgara eða hermanna.
How did the North American ice Saddle Collapse impact the climate 14,500 years ago?
Ivanovic, R. F.; Gregoire, L. J.; Wickert, A. D.; Valdes, P. J.; Gomez, N. A.
2014-12-01
Around 14.5 ka, global sea level rose by around 15 m in less than 350 years (e.g. Deschamps et al., 2012) during an event known as Meltwater Pulse 1a (MWP1a). Modelling work by Gregoire et al. (2012) suggested that around half of this ~50 mm yr-1 sea level rise was caused by accelerated collapse of the ice saddle between the N. American, Cordilleran and Laurentide Ice Sheets. Sea level records place MWP1a in the Bolling-Allerod period, a time of Northern Hemisphere warmth, but dating uncertainties make it difficult to determine the sequence of events and their drivers, leaving many fundamental questions. For example, did the abrupt ice saddle collapse and melting from other ice masses have any detectable climatic impact, or were there no feedbacks? Was melting from the Northern Hemisphere ice sheets responsible for the Older-Dryas (Menviel et al., 2011) or other cooling events? And how were all these signals linked to changes in ocean overturning circulation? To evaluate ice sheet impacts on climate during the Bolling, we integrate ice sheet, solid earth, drainage and climate modelling. We examine the effects of changing orography and meltwater inputs by combining ice-sheet model results, including the significant Laurentide-Cordilleran ice saddle collapse (Gregoire et al., 2012) and a new model of Antarctic ice sheet evolution (Gomez et al., 2013), with the ICE-5G reconstruction (Peltier et al., 2004). We route meltwater to the oceans using a high-resolution drainage calculation (Wickert et al., 2013). These modelled changes in global ice sheet topography and meltwater routing are then used to force the HadCM3 Ocean-Atmosphere-Vegetation general circulation model (using the 15 ka set-up of Singarayer and Valdes, 2010). We compare the climate model results to proxy records for temperature and ocean circulation changes during the Bolling warming and the Older Dryas to evaluate the different hypotheses on the link between MWP1a and climate change.
Polymerization, the Problem of Access to the Saddle Point Approximation, and Thermodynamics
Morales-Técotl, Hugo A; Rastgoo, Saeed
2016-01-01
The saddle point approximation to the partition functions is an important way of deriving the thermodynamical properties of black holes. However, there are certain black hole models and some mathematically analog mechanical models for which this method can not be applied directly. This is due to the fact that their action evaluated on a classical solution is not finite and its first variation does not vanish for all consistent boundary conditions. These problems can be dealt with by adding a counter-term to the classical action, which is a solution of the corresponding Hamilton-Jacobi equation. In this work however, we seek an alternative solution to this problem via the polymer quantization which is motivated by the loop quantum gravity.
THz-waves channeling in a monolithic saddle-coil for Dynamic Nuclear Polarization enhanced NMR.
Macor, A; de Rijk, E; Annino, G; Alberti, S; Ansermet, J-Ph
2011-10-01
A saddle coil manufactured by electric discharge machining (EDM) from a solid piece of copper has recently been realized at EPFL for Dynamic Nuclear Polarization enhanced Nuclear Magnetic Resonance experiments (DNP-NMR) at 9.4 T. The corresponding electromagnetic behavior of radio-frequency (400 MHz) and THz (263 GHz) waves were studied by numerical simulation in various measurement configurations. Moreover, we present an experimental method by which the results of the THz-wave numerical modeling are validated. On the basis of the good agreement between numerical and experimental results, we conducted by numerical simulation a systematic analysis on the influence of the coil geometry and of the sample properties on the THz-wave field, which is crucial in view of the optimization of DNP-NMR in solids.
Finite element method based on combination of "saddle point" variational formulations
Institute of Scientific and Technical Information of China (English)
周天孝
1997-01-01
A modified mixed/hybrid finite element method, which is no longer required to satisfy the Babuska-Brezzi condition, is referred to as a stabilized method Based on the duality of vanational principles in solid mechanics, a new type of stabilized method, called the combinatorially stabilized mixed/hybrid finite element method, is presented by weight-averaging both the primal and the dual "saddle-point" schemes. Through a general analysis of stability and convergence under an abstract framework, it is shown that for the methods only an inf-sup inequality much weaker than Babuska-Brezzi condition needs to be satisfied. As a concrete application, it is concluded that the combinatorially stabilized Raviart and Thomas mixed methods permit the C -elements to replace the H(div; Ω)-elements.
Spin States of Iron(III) in Highly Saddled Dodecaphenylporphyrin Complexes
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Ohya, T., E-mail: ohyat@pharm.teikyo-u.ac.jp; Takeda, J.; Sato, M. [Teikyo University, Laboratory of Biophysics, Faculty of Pharmaceutical Sciences (Japan)
2004-12-15
Iron(III) complexes of highly saddled dodecaphenylporphyrin, Fe(DPP)X (X=Cl, Br or I) have been prepared and characterized by Moessbauer, UV-Vis and magnetic measurements. The Moessbauer spectra, recorded at temperatures from 5 to 300 K, contain two components A and B. Component A is attributed to iron(III) in a spin-admixed (S=3/2, 5/2) state. The UV-Vis spectra of solution samples of these complexes exhibit broad and red-shifted absorption bands. The effective magnetic moments derived from the molar magnetic susceptibilities measured by modified Gouy method at 298 K for X=Cl, Br and I are 5.52, 5.10 and 4.28 {mu}{sub B}, respectively.
SADDLE-POINT BASED SEPARATION OF TOUCHED OBJECTS IN 2-D IMAGE
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
In many image analysis and processing problems, discriminating the size and shape of each individual object in an aggregate pile projected in an image is an important practice. It is relatively easy to distinguish these features among the objects already separated from each other. The problems will be undoubtedly more complex and of greater challenge if the objects are touched or/and overlapped. This letter presents an algorithm that can be used to separate the touches and overlaps existing in the objects within a 2-D image. The approach is first to convert the gray-scale image to its corresponding binary one and then to the 3-D topographic one using the erosion operations. A template (or mask) is engineered to search the topographic surface for the saddle point, from which the segmenting orientation is determined followed by the desired separating operation. The algorithm is tested on a real image and the running result is adequately satisfying and encouraging.
Back in the saddle: Large-deviation statistics of the cosmic log-density field
Uhlemann, Cora; Pichon, Christophe; Bernardeau, Francis; Reimberg, Paulo
2015-01-01
We present a first principle approach to obtain analytical predictions for spherically-averaged cosmic densities in the mildly non-linear regime that go well beyond what is usually achieved by standard perturbation theory. A large deviation principle allows us to compute the leading-order cumulants of average densities in concentric cells. In this symmetry, the spherical collapse model leads to cumulant generating functions that are robust for finite variances and free of critical points when logarithmic density transformations are implemented. They yield in turn accurate density probability distribution functions (PDFs) from a straightforward saddle-point approximation valid for all density values. Based on this easy-to-implement modification, explicit analytic formulas for the evaluation of the one- and two-cell PDF are provided. The theoretical predictions obtained for the PDFs are accurate to a few percent compared to the numerical integration, regardless of the density under consideration and in excellen...
NMR difference spectroscopy with a dual saddle-coil difference probe.
Macnaughtan, Megan A; Smith, Aaron P; Goldsbrough, Peter B; Santini, Robert E; Raftery, Daniel
2004-03-01
A new difference probe for nuclear magnetic resonance (NMR) spectroscopy is presented. The difference probe uses two saddle-shaped coils to excite and detect two samples simultaneously. The samples are held in a specially modified 3-mm NMR tube with an Ultem plastic disk to separate the samples. The probe's resonant circuit contains two crossed diodes that passively switch the relative phase of each coil during the NMR experiment. The result is a difference spectrum from the two samples. The degree of cancellation of common signals was determined to be approximately 90%, and the application of the probe to relaxation-edited difference spectroscopy for identifying protein-ligand interactions was demonstrated using glutathione and glutathione S-transferase binding protein.
Saddles, arrows, and spirals: deterministic trajectories in cyclic competition of four species.
Durney, C H; Case, S O; Pleimling, M; Zia, R K P
2011-05-01
Population dynamics in systems composed of cyclically competing species has been of increasing interest recently. Here we investigate a system with four or more species. Using mean field theory, we study in detail the trajectories in configuration space of the population fractions. We discover a variety of orbits, shaped like saddles, spirals, and straight lines. Many of their properties are found explicitly. Most remarkably, we identify a collective variable that evolves simply as an exponential: Q ∝ e(λt), where λ is a function of the reaction rates. It provides information on the state of the system for late times (as well as for t→-∞). We discuss implications of these results for the evolution of a finite, stochastic system. A generalization to an arbitrary number of cyclically competing species yields valuable insights into universal properties of such systems.
Critical conditions of saddle-node bifurcations in switching DC-DC converters
Fang, Chung-Chieh
2013-08-01
Although existence of multiple periodic orbits in some DC-DC converters have been known for decades, linking the multiple periodic orbits with the saddle-node bifurcation (SNB) is rarely reported. The SNB occurs in popular DC-DC converters, but it is generally reported as a strange instability. Recently, design-oriented instability critical conditions are of great interest. In this article, average, sampled-data and harmonic balance analyses are applied and they lead to equivalent results. Many new critical conditions are derived. They facilitate future research on the instability associated with multiple periodic orbits, sudden voltage jumps or disappearances of periodic orbits observed in DC-DC converters. The effects of various converter parameters on the instability can be readily seen from the derived critical conditions. New Nyquist-like plots are also proposed to predict or prevent the occurrence of the instability.
Institute of Scientific and Technical Information of China (English)
XING Yong-Zhong
2009-01-01
The analytical solution of a multidimensional Langevin equation at the overdamping limit is obtained and the probability of particles passing over a two-dimensional saddle point is discussed. These results may break a path for studying further the fusion in superheavy elements synthesis.
Institute of Scientific and Technical Information of China (English)
JIA Bing; GU Hua-Guang; LI Yu-Ye
2011-01-01
@@ Excitability is an essential characteristic of excitable media such as nervous and cardiac systems.Different types of neuronal excitability are related to different bifurcation structures.We simulate the coherence resonance effect near a saddle-node and homoclinic bifurcation corresponding to type-I excitability in a theoretical neuron model,and recognize the obvious features of the corresponding firing pattern.Similar firing patterns are discovered in rat hippocampal CA1 pyramidal neurons.The results are not only helpful for understanding the dynamics of the saddle-node bifurcation and type-I excitability in a realistic nervous system,but also provide a practical indicator to identify types of excitability and bifurcation.%Excitability is an essential characteristic of excitable media such as nervous and cardiac systems. Different types of neuronal excitability are related to different bifurcation structures. We simulate the coherence resonance effect near a saddle-node and homoclinic bifurcation corresponding to type-I excitability in a theoretical neuron model, and recognize the obvious features of the corresponding firing pattern. Similar firing patterns are discovered in rat hippocampal CA1 pyramidal neurons. The results are not only helpful for understanding the dynamics of the saddle-node bifurcation and type-I excitability in a realistic nervous system, but also provide a practical indicator to identify types of excitability and bifurcation.
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C. Wallace
1977-08-01
Full Text Available Among the present-day members of the Canidae family are included the dogs and foxes (Wurster and Benirschke 1968. The genus Canis is represented in Africa by four species of jackal (Bigaike 1972. This paper presents the chromosome Findings in a male saddle-backed jackal Canis mesomelas studied in the Kruger National Park, Republic of South Africa.
VANDERLEI, B; HOEKSTRA, HJ; VETH, RPH; HAM, SJ; OLDHOFF, J; KOOPS, HS
1992-01-01
Reconstruction of the hip joint by a saddle prosthesis after excision of a malignant pelvic tumor is a relatively new method, which thus far has been mainly used for revision of infected hip arthroplasties. One patient with a metastatic cystosarcoma phyllodes and one patient with a chondrosarcoma of
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Susmita Bhattacharyya
2015-01-01
Full Text Available Background: Spinal anesthesia is the technique of choice in transurethral resection of prostate (TURP. The major complication of spinal technique is risk of hypotension. Saddle block paralyzed pelvic muscles and sacral nerve roots and hemodynamic derangement is less. Aims and objectives: To compare the hemodynamic changes and adequate surgical condition between saddle block and subarachnoid block for TURP. Material and methods: Ninety patients of aged between 50 to 70 years of ASA-PS I, II scheduled for TURP were randomly allocated into 2 groups of 45 in each group. Group A patients were received spinal (2 ml of hyperbaric bupivacaine and Group B were received saddle block (2 ml of hyperbaric bupivacaine. Baseline systolic, diastolic and mean arterial pressure, heart rate, oxygen saturation were recorded and measured subsequently. The height of block was noted in both groups. Hypotension was corrected by administration of phenylephrine 50 mcg bolus and total requirement of vasopressor was noted. Complications (volume overload, TURP syndrome etc. were noted. Results: Incidence of hypotension and vasopressor requirement was less (P < 0.01 in Gr B patients.Adequate surgical condition was achieved in both groups. There was no incidence of volume overload, TURP syndrome, and bladder perforation. Conclusion: TURP can be safely performed under saddle block without hypotension and less vasopressor requirement.
SORIA CABELLO, ÁLVARO
2015-01-01
[EN] Documents founded in this page as Final Degree Thesis include both the construction process and the budget needed to carry out the solution presented to the Basic Project ¿Proyecto Básico para el concurso del Puente de acceso sur al parque de Tempelhof, Berlín¿. For the design of the construction process, we have taken into account all factors that could affect such as the reducing schedule due to the existance of the Railways, the possible problems with the trains, access to machinery, ...
Directory of Open Access Journals (Sweden)
Eneko Besa
2012-12-01
Full Text Available
Resumen
Estudio de la Filarmónica de Berlín como ejemplo de las diferentes aproximaciones y contradicciones que la arquitectura “traba” a través del argumento que la constituye. Acuerdo tenso entre interior‐exterior, lugar‐programa, simetría‐asimetría, unidad sintética ‐ complejidad múltiple, continuidad orgánica ‐ discontinuidad fragmentada.
Comparativa con el edificio Walt Disney Concert Hall, en el que se utiliza la misma tipología de sala de conciertos. Sin embargo y al contrario que Scharoun, Gehry evita cualquier acuerdo sintético de unidad, constituyendo el edificio a partir de la pura fragmentación y diversidad per se. Pues en su caso, la unidad necesaria para constituir la autonomía y ser de la obra, se buscará a través de la imagen y expresión del concepto de belleza que el edificio alcanza.
Palabras clave
sala de conciertos, lugar, unidad, exterior, fragmento
Abstract
This article is a study of the Berlin Philharmonic Concert Hall as an example of the different approximations and contradictions that Architecture ties together as a result of the reasoning that makes it up. A tense agreement between interior and exterior, place and program, symmetry and asymmetry, synthetic unity and multiple complexity, organic continuity and fragmented discontinuity.
A comparison to Walt Disney Concert Hall is made, where the same concert hall typology is used. Nevertheless, in contrast to Scharoun, Gehry avoids any kind of synthetic agreement of unity, conceiving the building out of pure fragmentation and diversity per se. In Gehry’s case, the unity necessary to constitute the autonomy and essence of the building is sought through the image and expression of the concept of beauty that it reaches.
Key words
concert hall, place, unity, exterior, fragment
Greve, Line; Murray, Rachel; Dyson, Sue
2015-10-01
Recommendations concerning saddle-fit are empirical rather than based on scientific information. A saddle needs to fit the horse in motion, but there has been no investigation of whether the thoracolumbar region changes in dimensions in association with exercise. The objectives of this study were to quantify exercise-induced back dimension changes and to describe the association with work quality, saddle-fit and rider skill. Sixty-three sports horses in regular work were assessed prospectively in a non-random, cross-sectional survey. Thoracolumbar dimensions/symmetries were measured at predetermined sites before and immediately after a 30 min exercise period; widths for two levels at each site were measured and the shape-ratio calculated. The work quality and rider skill were graded and the presence of lameness and saddle-fit were recorded. Descriptive statistics, univariable and multivariable mixed-effect linear regression were performed to assess the relationship between horse-saddle-rider factors and changes in back dimensions. The mean back width after ridden exercise was greater compared with before exercise. Mean changes were greater in horses working correctly vs. those not working correctly, in those with correctly-fitting vs. ill-fitting saddles, and in horses ridden by good > moderately > poorly skilled riders. Back-width changes were significantly associated with saddle-fit. The back dimensions of horses working correctly change transiently with work. If a saddle does not fit properly before exercise, this increase in size does not occur. Saddle-fit should be assessed both before and after exercise to ensure correct fit.
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Stuart Leigh Phoenix
2017-03-01
Full Text Available Yarn shooting experiments were conducted to determine the ballistically-relevant, Young’s modulus and tensile strength of ultra-high molecular weight polyethylene (UHMWPE fiber. Target specimens were Dyneema® SK76 yarns (1760 dtex, twisted to 40 turns/m, and initially tensioned to stresses ranging from 29 to 2200 MPa. Yarns were impacted, transversely, by two types of cylindrical steel projectiles at velocities ranging from 150 to 555 m/s: (i a reverse-fired, fragment simulating projectile (FSP where the flat rear face impacted the yarn rather than the beveled nose; and (ii a ‘saddle-nosed projectile’ having a specially contoured nose imparting circular curvature in the region of impact, but opposite curvature transversely to prevent yarn slippage off the nose. Experimental data consisted of sequential photographic images of the progress of the triangular transverse wave, as well as tensile wave speed measured using spaced, piezo-electric sensors. Yarn Young’s modulus, calculated from the tensile wave-speed, varied from 133 GPa at minimal initial tension to 208 GPa at the highest initial tensions. However, varying projectile impact velocity, and thus, the strain jump on impact, had negligible effect on the modulus. Contrary to predictions from the classical Cole-Smith model for 1D yarn impact, the critical velocity for yarn failure differed significantly for the two projectile types, being 18% lower for the flat-faced, reversed FSP projectile compared to the saddle-nosed projectile, which converts to an apparent 25% difference in yarn strength. To explain this difference, a wave-propagation model was developed that incorporates tension wave collision under blunt impact by a flat-faced projectile, in contrast to outward wave propagation in the classical model. Agreement between experiment and model predictions was outstanding across a wide range of initial yarn tensions. However, plots of calculated failure stress versus yarn pre
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Baumgarten, Paul
1964-04-01
Full Text Available This new church, suitable for a seated congregation of 700, including those occupying the choir and baptistry, takes the place of the old one, made of timber, which was destroyed during the war. In addition to the church itself, there is a Sunday school, a sacristy, and living quarters for the sacristan. The organ, orchestra and choir are situated at a higher level, over the church hall. The churchtower has three campaniles, all at the same level. No attempt has been made to emphasize the tower as a dominant feature, as anyway it cannot compete in height with the surrounding buildings. More importance has been attached to the general architectural quality of the building, both in its internal and external expression. A design has been attempted which reflects from the outside the religious character of the interior, whilst fitting well with the charming landscape of the Lietzen lakedistrict. In the final design a number of factors were decisive. Religious, accoustical, structural and human requirements were taken into account. These led also to the choice of the roof, which is formed by a number of triangular shape, and to the fitting of large surfaces of stained glass. Through this the interior is illuminated from all sides, and a greater continuity seems to be established with the green spaces beyond. The project does reflect strongly its essential quality as «the house of God»: this is emphasized by the structural and topological arrangement of its parts, and by the spontaneous manner in which the sight is drawn towards the altar.Esta iglesia, de nueva planta, con 700 asientos—incluidos los del coro y baptisterio—, reemplaza- a la de madera que fue destruida durante la guerra. Dispone de locales para catequesis, sacristía y vivienda del sacristán. Tiene una entreplanta para el órgano, la orquesta y el coro, sobre la cual se levanta el campanario, con tres campaniles colocados uno dominante por no poder competir con las casas altas que le rodean, lado del otro, al que no se ha intentado realzar como elemento dominante por no poder competir con las casas altas que le rodean. Se concedió mayor importancia, en la concepción general arquitectónica, a la forma interior y exterior que a los rasgos urbanísticos, logrando crear un recinto cuyo aspecto externo refleja el carácter religioso del interior y que armoniza con el bello paisaje de la zona del lago Lietzen. En la determinación de dicha forma influyeron varios factores, no sólo de tipo religioso, sino también de orden acústico, estructural y ambiental, que condujeron a la cubierta actual—constituida por una serie de triángulos—y a las grandes vidrieras que cuajan profusamente las superficies exentas. A través de ellas, el interior recibe luz por todos los lados en que se desea un mayor contacto con las zonas verdes exteriores. No obstante, se ha conseguido, acertadamente, conservar el carácter de «casa de Dios», de tabernáculo, carácter que viene acusado por la concentración estructural, direccional y visual de las superficies de la cubierta, hacia el altar.
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Schneider-Esleben, P.
1960-03-01
Full Text Available Este edificio de cuatro plantas corresponde a un grupo de cinco construcciones iguales situadas al norte de la parcela que constituye el barrio Hansa, entre la calle Klopstock y el Stadt-Bahn, famoso ferrocarril urbano berlinés. El bloque de 56 m de longitud por 9 de anchura y 12 de altura, consta de veinte viviendas. Cada vivienda, de 77 m2, está distribuida en dos plantas: la baja aloja el cuarto de estar y la cocina y la alta el baño y los dormitorios.
Parametric CAD and Fea Model of a Saddle Tapping Tee
DEFF Research Database (Denmark)
A. Kristensen, Anders Schmidt; Lund Jepsen, Kristian
2007-01-01
pressure 30[bar]. A parametric verification model is established based on considerations regarding the compaction of the gasket and the stress level in the brackets of the clamp. The required minimum compaction pressure in the gasket is 1.4[N/mm] according to the European Norm for pressure vessels DS EN...... is determined from paragraph K302.3.2 in ASME B31.3. A full parametric 3D CAD model of the Saddle Tapping Tee is developed where a number of user-defined parameters are controlled from an Excel spreadsheet allowing parameter studies and technical documentation to be generated effectively. The same Excel spread......-sheet control a full 3D parametric FEA model which is automatically updated from the user-defined parameters set for the CAD-model. As the gasket is subjected to a contact pressure arising from the clamping force acting on the pipe section, a FE contact analysis is carried out. This contact analysis is set up...
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Fabiana M. Flores
2015-06-01
Full Text Available Background: Hippotherapy uses horseback riding movements for therapeutic purposes. In addition to the horse's movement, the choice of equipment and types of floor are also useful in the intervention. The quantification of dynamic parameters that define the interaction of the surface of contact between horse and rider provides insight into how the type of floor surface variations act upon the subject's postural control. Objective: To test whether different types of surfaces promote changes in the amplitude (ACOP and velocity (VCOP of the center of pressure (COP displacement during the rider's contact with the saddle on the horse's back. Method: Twenty two healthy adult male subjects with experience in riding were evaluated. The penetration resistances of asphalt, sand and grass surfaces were measured. The COP data were collected on the three surfaces using a pressure measurement mat. Results: ACOP values were higher in sand, followed by grass and asphalt, with significant differences between sand and asphalt (anteroposterior, p=0.042; mediolateral, p=0.019. The ACOP and VCOP values were higher in the anteroposterior than in the mediolateral direction on all surfaces (ACOP, p=0.001; VCOP, p=0.006. The VCOP did not differ between the surfaces. Conclusion: Postural control, measured by the COP displacement, undergoes variations in its amplitude as a result of the type of floor surface. Therefore, these results reinforce the importance of the choice of floor surface when defining the strategy to be used during hippotherapy intervention.
A smooth landscape: ending saddle point inflation requires features to be shallow
Energy Technology Data Exchange (ETDEWEB)
Battefeld, Diana; Battefeld, Thorsten, E-mail: dbattefe@astro.physik.uni-goettingen.de, E-mail: tbattefe@astro.physik.uni-goettingen.de [Institute for Astrophysics, University of Goettingen, Friedrich Hund Platz 1, D-37077 Goettingen (Germany)
2013-07-01
We consider inflation driven near a saddle point in a higher dimensional field space, which is the most likely type of slow roll inflation on the string theoretical landscape; anthropic arguments need to be invoked in order to find a sufficiently flat region. To give all inflatons large masses after inflation and yield a small but positive cosmological constant, the trajectory in field space needs to terminate in a hole on the inflationary plateau, introducing a curved end-of-inflation hypersurface. We compute non-Gaussianities (bi- and tri-spectrum) caused by this curved hyper-surface and find a negative, potentially large, local non-linearity parameter. To be consistent with current observational bounds, the hole needs to be shallow, i.e. considerably wider than deep in natural units. To avoid singling out our vacuum as special (i.e. more special than a positive cosmological constant entails), we deduce that all features on field space should be similarly shallow, severely limiting the type of landscapes one may use for inflationary model building. We justify the use of a truncated Fourier series with random coefficients, which are suppressed the higher the frequency, to model such a smooth landscape by a random potential, as is often done in the literature without a good a priory reason.
Otranto, Sebastian
2014-10-01
During the last few years, several experimental and theoretical studies have focused on state selective charge exchange processes between charged ions and alkali metals. These data are of particular importance for the tokamak nuclear fusion reactor program, since diagnostics on the plasma usually rely on charge-exchange spectroscopy. In this sense, alkali metals, have been proposed as potential alternatives to excited hydrogen/deuterium for which laboratory experiments are not feasible at present. In this talk, we present our recent work involving ion collisions with alkali metals. Oscillatory structures in the angular differential charge-exchange cross sections obtained using the MOTRIMS technique are correctly described by classical trajectory Monte Carlo simulations. These oscillations are found to originate from the number of swaps the electron undergoes around the projectile-target potential saddle before capture takes place and are very prominent at impact energies below 10 keV/amu. Moreover, cross sections of higher order of differentiability also indicate that the swaps leave distinctive signatures in the (n,l)-state selective cross sections and in the photon line emission cross sections. Oscillatory structures for the x-ray hardness ratio parameter are also predicted. In collaboration with Ronnie Hoekstra, Zernike Institute for Advanced Materials, University of Groningen and Ronald Olson, Department of Physics, Missouri University of Science and Technology.
Application of an AM-BLUP to the station test results of Italian Saddle horse stallions
Directory of Open Access Journals (Sweden)
C. Pieramati
2010-04-01
Full Text Available The data collected in the first seven years of the 100-day Station Test for Italian Saddle Horse stallions have been used to estimate EBVs by single trait - repeatability AM-BLUP. There were 9449 scores for “character” and “gaits”, and 3564 for “jumping ability” in the training period; 344 scores for each trait were also available from the final evaluations assigned by two well-known professional riders; in the pedigree file of the 180 tested horses there were 2837 animals. Heritability estimates were .38±.02 and .23±.14 for “character”, .60±.02 and .58±.04 for “gaits”, and .48±.02 and .52±.04 for “jumping”, in the training period and in the final evaluation, respectively. The training period and the final evaluation were weighted 90% and 10% in each trait index, and the weights for “character”, “gaits” and “jumping” were 25%, 25% and 50% in the overall index. The genetic index was correlated .97 with the current official index, both linearly and in rank: therefore, the 82 licensed stallions give a selection intensity of .85, instead of the theoretical maximum of .87. Although the difference in the response to selection that the switching to BLUP could assure is low, the breeders could make comparisons between stallions approved in different editions.
Flores, Fabiana M.; Dagnese, Frederico; Mota, Carlos B.; Copetti, Fernando
2015-01-01
Background: Hippotherapy uses horseback riding movements for therapeutic purposes. In addition to the horse's movement, the choice of equipment and types of floor are also useful in the intervention. The quantification of dynamic parameters that define the interaction of the surface of contact between horse and rider provides insight into how the type of floor surface variations act upon the subject's postural control. Objective: To test whether different types of surfaces promote changes in the amplitude (ACOP) and velocity (VCOP) of the center of pressure (COP) displacement during the rider's contact with the saddle on the horse's back. Method: Twenty two healthy adult male subjects with experience in riding were evaluated. The penetration resistances of asphalt, sand and grass surfaces were measured. The COP data were collected on the three surfaces using a pressure measurement mat. Results: ACOP values were higher in sand, followed by grass and asphalt, with significant differences between sand and asphalt (anteroposterior, p=0.042; mediolateral, p=0.019). The ACOP and VCOP values were higher in the anteroposterior than in the mediolateral direction on all surfaces (ACOP, p=0.001; VCOP, p=0.006). The VCOP did not differ between the surfaces. Conclusion: Postural control, measured by the COP displacement, undergoes variations in its amplitude as a result of the type of floor surface. Therefore, these results reinforce the importance of the choice of floor surface when defining the strategy to be used during hippotherapy intervention. PMID:26083600
Properties of diffusive systems near a saddle point: application to a quartic double well
Energy Technology Data Exchange (ETDEWEB)
Battezzati, M [Istituto di Cosmo-Geofisica del CNR, Reparto di Fisica cosmica, corso Fiume 4, 10133 Turin (Italy)
2003-04-04
This paper aims at the analysis of diffusive properties of unidimensional mechanical systems in the environment of maxima and minima of the potential. It begins with a study of the properties of the singular solutions of the Hamilton-Jacobi-Yasue equation in the above-mentioned environment, in both strong or very small frictional forces. For the quartic symmetrical double-well potential, approximate solutions are found for local validity and the diffusion operator is then calculated in the limits of deep wells and small temperature, the regime being supposed to be aperiodic, with high or moderate values of frictional coefficient. This equation is proved to be nonunique. This operator is then reduced to second order by imposing suitable boundary conditions. Thus an appropriate eigenvalue equation is obtained to describe stationary states in the environment of extremal points of the potential energy function. The main interest of this work relies upon the fact that transition times between wells mainly depend upon fluctuations near the saddle point.
[Evaluation of orthostatic regulation by saddle support test using thoracic impedance].
Gugova, F K; Lapin, V V
2002-01-01
We investigated 21 healthy volunteers (10 males and 11 females, mean age 23 +/- 4 years). All the subjects have undergone two 20 min head-up tilt tests using tilt table "TRI W.G. inc." (USA): the first with footplate support and the second with bicycle saddle. Thoracic electrical impedance was measured using impedance cardiography according to Kubicek et al. The protocols included an initial period of 20 min of supine rest while baseline thoracic impedance, blood pressure and heart rate were recorded and then followed by a tilt to 65 degrees. Changes of impedance were measured at min 1, 2, 3, 5, 7, 10, 15, 20 after the procedure. Women had higher values of thoracic impedance both at rest and during the tilt test than men. The value of impedance of the chest negatively correlated with the body mass index. We suppose that an increase of impedance more than 15% may be related with pathological venous pooling. Thoracic impedance may be used to monitor changes of thoracic fluid volumes with posture and possibly to assess orthostatic regulation. The contribution of leg muscles in orthostatic regulation does not reflect values of thoracic impedance.
Institute of Scientific and Technical Information of China (English)
Cui Jia; Ruan Xin; Zhou Xiaoyi
2011-01-01
The traffic condition of Taizhou Yangtze River Bridge is obtained to a certain extent, according to the traffic investigation nearby Taizhou Bridge. The statistical characteristics of the traffic conditions are acquired by statistical analysis. Simulation of the extreme vehicle loads and the sensitive analysis of load parameters are carried out based on these data complemented, which would guide the determination of the frictional coefficient between the main cables and the saddle.
Strength Proofread of Saddle Support on Blast Furnace Hot Metal Ladle Car%高炉铁水罐车支座的强度校核
Institute of Scientific and Technical Information of China (English)
郝晓静
2013-01-01
In this paper , the strength caculation of saddle support of the hot metal ladle car on BF is intro-duced.It will be helpful to the new transfer car designing of the saddle support .%对高炉铁水罐车罐支座的强度进行了计算，为新规格铁水车的支座设计提供了理论依据。
Directory of Open Access Journals (Sweden)
Fabiano Lemos
2011-01-01
proceso de estructuración de los museos y la reestructuración de las colecciones de historia natural en ciudades como París y Berlín en la transición para el siglo XIX, para convencernos del asombro con el origen que ya no se reconoce y que se convierte en objeto de interés científico y popular, y que guió cada una de las decisiones involucradas en este proceso. El museo es sólo una de las instituciones en que el hombre, a través de una serie idealizaciones del espacio complejo, se entrega a el espectáculo de un tiempo perdido, y por lo tanto una cultura cuyo esfuerzo educativo sólo puede aprender asociándose a estas instituciones. Lo que debemos investigar - y el estudio de caso de la discusión en torno a la fundación del Museo Altes en Berlín entre 1822 y 1830 puede hacer estas investigaciones más concretas - es que las políticas institucionales han hecho posible el surgimiento de este nuevo modelo ideológico, y en sentido contrario, que elaboraciones conceptuales confirmaron y legitimaron la nueva topografía pragmática del tiempo en la modernidad dentro de la institución que tenía como objetivo, precisamente articular y gestionar el pasado y la memoria.
Desde a aurora do que hoje entendemos como modernidade o homem se espanta com sua finitude. O burguês dos séculos XVIII e XIX precisou elaborar intrincados mecanismos de preservação de passado e de vinculação com ele. No círculo dos philosophes, o conceito de tempo passa a se duplicar na idéia de origem, que, para eles, se tornou opaca. Basta pensarmos no amplo processo de estruturação dos museus e de reestruturação das coleções de história natural em cidades como Paris e Berlim, na passagem para o século XIX, para nos convencermos de que o assombro com a origem que não mais se reconhece, que se torna objeto de interesse científico e popular, orienta cada uma das decisões envolvidas neste processo. O museu é apenas uma das institui
鞍形CT的感兴趣区图像重建%ROI-image Reconstruction for a Saddle Trajectory
Institute of Scientific and Technical Information of China (English)
夏丹; 余立锋; 邹宇
2005-01-01
Recently, we have developed a general formula for 3D cone-beam CT reconstruction, which can accommondate general, smooth trajectories. From the formula, algorithms can be derived for image reconstruction within a region of interest (ROI) from truncated data. In this work, we apply the derived backprojection filteration (BPF) algorithm and the minimum-data filtered backprojection (MD-FBP) algorithm to reconstructing ROI images from cone-beam projection data acquired with a saddle trajec-tory. Our numerical results in these studies demonstrate that the BPF and MD-FBP algorithms can accurately reconstruct ROI images from truncated data.
五河定淮淮河特大桥索鞍安装施工技术%The five river Huai River Bridge saddle Installation Technology
Institute of Scientific and Technical Information of China (English)
梁学平
2014-01-01
五河定淮淮河特大桥斜拉索为同截面回转拉索体系，采用钢绞线拉索，以索塔斜置鞍座进行单向索锚索。鞍座为桥梁设计阶段专项研发产品，在此之前鞍座的定位安装无借鉴资料，故我项目针对索鞍安装定位存在的问题进行了分析研究，为索鞍式斜拉桥的推广应用提供依据。%Five Rivers given the Huai Huai River Bridge cable-stayed the same cross-section rotary cable system, strand cable, sarasota inclined saddle unidirectional cable anchor cable. Special saddle for the bridge design stage R & D products, before this saddle positioning instal no draw on data. Therefore, my project for the cable saddle instal ation positioning the problems analysis, To provide a basis for the promotion of the cable-stayed bridge saddles applications.
Vanne, Y V; Saenz, Alejandro; Vanne, Yulian V.
2006-01-01
In recent articles [Mishima et al., Phys. Rev. A, 66, 033401(2002); Chao, Phys. Rev. A, 72, 053414 (2005)] it was proposed to use the residue theorem for the exact calculation of the transition amplitude describing strong-field ionization of atomic systems within Keldysh theory. This should avoid the necessity to apply the method of steepest descent (saddle-point approximation). Comparing the results of both approaches for atomic hydrogen a difference by a factor of 2 was found for the 1s, and an even more drastic deviation for the 2s state. Thus it was concluded that the use of the saddle-point approximation is problematic. In this work the deviations are explained and it is shown that the previous conclusion is based on an unjustified neglect of an important contribution occurring in the application of the residue theorem. Furthermore, the applicability of the method of steepest descent for the ionization of Rydberg states is discussed and an improvement of the standard result is suggested that successfully...
Marqués, Fernando J; Waldner, Cheryl; Reed, Stephen; Autet, Fernando; Corbeil, Louise; Campbell, John
2014-04-01
The primary objective of this study was to investigate whether rider experience influences the assessment and grading of lameness in horses based on under-saddle gait analysis. Thirteen adult sports horses in active training were included in the study. After a baseline lameness and neurologic examination by the principal investigators, horses were videotaped while being ridden by an experienced and a less experienced rider. A 3-minute video was made for each horse and rider and 26 videos were randomly ordered and compiled on a DVD. Veterinarians with different levels of experience in evaluating lameness and veterinary students viewed the DVD and assigned a lameness score to each horse/rider combination. In a model accounting for the expertise of the evaluator, there was no difference in overall lameness scores between experienced and less experienced riders. This result was consistent for both sound and unsound horses. The overall lameness scores reported by specialists and students, however, differed significantly. The lameness score reported by the study participants while the horse was ridden was significantly associated with the subjective baseline lameness assessment reported by the principal investigators for the same limb when the horse was not under saddle. Additional work is necessary to determine whether riders with even lower skill levels would further alter the balance and motion pattern of the horse and have more influence on subjective grading of lameness.
Ivanovic, Ruza F.; Gregoire, Lauren J.; Wickert, Andrew D.; Valdes, Paul J.; Burke, Andrea
2017-01-01
Collapse of ice sheets can cause significant sea level rise and widespread climate change. We examine the climatic response to meltwater generated by the collapse of the Cordilleran-Laurentide ice saddle (North America) 14.5 thousand years ago (ka) using a high-resolution drainage model coupled to an ocean-atmosphere-vegetation general circulation model. Equivalent to 7.26 m global mean sea level rise in 340 years, the meltwater caused a 6 sverdrup weakening of Atlantic Meridional Overturning Circulation (AMOC) and widespread Northern Hemisphere cooling of 1-5°C. The greatest cooling is in the Atlantic sector high latitudes during Boreal winter (by 5-10°C), but there is also strong summer warming of 1-3°C over eastern North America. Following recent suggestions that the saddle collapse was triggered by the Bølling warming event at 14.7-14.5 ka, we conclude that this robust submillennial mechanism may have initiated the end of the warming and/or the Older Dryas cooling through a forced AMOC weakening.
Dey, Santanu
2012-01-01
We consider the problem of efficient simulation estimation of the density function at the tails, and the probability of large deviations for a sum of independent, identically distributed, light-tailed and non-lattice random vectors. The latter problem besides being of independent interest, also forms a building block for more complex rare event problems that arise, for instance, in queuing and financial credit risk modeling. It has been extensively studied in literature where state independent exponential twisting based importance sampling has been shown to be asymptotically efficient and a more nuanced state dependent exponential twisting has been shown to have a stronger bounded relative error property. We exploit the saddle-point based representations that exist for these rare quantities, which rely on inverting the characteristic functions of the underlying random vectors. We note that these representations reduce the rare event estimation problem to evaluating certain integrals, which may via importance ...
Institute of Scientific and Technical Information of China (English)
YOOER Chi-Feng; XU Jian-Xue; ZHANG Xin-Hua
2009-01-01
Mechanism of period-adding cascades with chaos in a reduced leech neuron model is suggested as the bifurcation of a saddle-node limit cycle with homoclinic orbits satisfying the "small lobe condition",instead of the blue-sky catastrophe.In every spiking adding,the new spike emerges at the end of the spiking phase of the bursters.
Energy Technology Data Exchange (ETDEWEB)
Santos, T.J.; Carlson, B.V., E-mail: nztiago@gmail.com [Instituto Tecnologia de Aeronautica (ITA), Sao Jose dos Campos, SP (Brazil)
2014-07-01
One of the principal characteristics of nuclear multifragmentation is the emission of complex fragments of intermediate mass. The statistical multifragmentation model has been used for many years to describe the distribution of these fragments. An extension of the statistical multifragmentation model to include partial widths and lifetimes for emission, interprets the fragmentation process as the near simultaneous limit of a series of sequential binary decays. In this extension, the expression describing intermediate mass fragment emission is almost identical to that of light particle emission. At lower temperatures, similar expressions have been shown to furnish a good description of very light intermediate mass fragment emission. However, this is usually not considered a good approximation to the emission of heavier fragments. These emissions seem to be determined by the characteristics of the system at the saddle-point and its subsequent dynamical evolution rather than by the scission point. Here, we compare the barriers and decay widths of these different formulations of intermediate fragment emission and analyze the extent to which they remain distinguishable at high excitation energy. (author)
Energy Technology Data Exchange (ETDEWEB)
Wissman, J., E-mail: jwissman@andrew.cmu.edu [Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Finkenauer, L. [Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Deseri, L. [DICAM, Department of Mechanical, Civil and Environmental Engineering, University of Trento, via Mesiano 77 38123 Trento (Italy); TMHRI-Department of Nanomedicine, The Methodist Hospital Research Institute, 6565 Fannin St., MS B-490 Houston, Texas 77030 (United States); Mechanics, Materials and Computing Center, CEE and ME-CIT, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Majidi, C. [Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Robotics Institute and Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States)
2014-10-14
We introduce a dielectric elastomer actuator (DEA) composed of liquid-phase Gallium-Indium (GaIn) alloy electrodes embedded between layers of poly(dimethylsiloxane) (PDMS) and examine its mechanics using a specialized elastic shell theory. Residual stresses in the dielectric and sealing layers of PDMS cause the DEA to deform into a saddle-like geometry (Gaussian curvature K<0). Applying voltage Φ to the liquid metal electrodes induces electrostatic pressure (Maxwell stress) on the dielectric and relieves some of the residual stress. This reduces the longitudinal bending curvature and corresponding angle of deflection ϑ. Treating the elastomer as an incompressible, isotropic, NeoHookean solid, we develop a theory based on the principle of minimum potential energy to predict the principal curvatures as a function of Φ. Based on this theory, we predict a dependency of ϑ on Φ that is in strong agreement with experimental measurements performed on a GaIn-PDMS composite. By accurately modeling electromechanical coupling in a soft-matter DEA, this theory can inform improvements in design and fabrication.
Measures to Solve Depression Defects of Saddle%滑板铸件缩陷缺陷的解决
Institute of Scientific and Technical Information of China (English)
杨明; 刘志青; 贾晓波
2011-01-01
分析了床鞍滑板铸件产生缩陷的原因,并提出了相应的解决措施.通过在熔炼过程中调整废钢、生铁加入量,以调节铸件含碳量,使铸件凝固收缩率减小;更改分型面及浇注位置等一系列工艺措施,使铸件的废品得到了有效地控制.%The reason causes depression of skateboard bad saddle was analyzed, and the corresponding solutions were put forward. By taking a series of technical measures the rejection rate was reduced effectively, and obtained a certain economic benefit. The measures are that adjusting lhe addition amount of scrap steel and pig iron in smelting process to adjust carbon content of casting products, and changing the location of parting face and gates, so as to decrease the solidification shrinkage rate.
Gregoire, Lauren J.; Otto-Bliesner, Bette; Valdes, Paul J.; Ivanovic, Ruza
2016-09-01
Elucidating the source(s) of Meltwater Pulse 1a, the largest rapid sea level rise caused by ice melt (14-18 m in less than 340 years, 14,600 years ago), is important for understanding mechanisms of rapid ice melt and the links with abrupt climate change. Here we quantify how much and by what mechanisms the North American ice sheet could have contributed to Meltwater Pulse 1a, by driving an ice sheet model with two transient climate simulations of the last 21,000 years. Ice sheet perturbed physics ensembles were run to account for model uncertainties, constraining ice extent and volume with reconstructions of 21,000 years ago to present. We determine that the North American ice sheet produced 3-4 m global mean sea level rise in 340 years due to the abrupt Bølling warming, but this response is amplified to 5-6 m when it triggers the ice sheet saddle collapse.
Podolsky, Dmitry
2012-01-01
For a power system operating in the vicinity of the power transfer limit of its transmission system, effect of stochastic fluctuations of power loads can become critical as a sufficiently strong such fluctuation may activate voltage instability and lead to a large scale collapse of the system. Considering the effect of these stochastic fluctuations near a codimension 1 saddle-node bifurcation, we explicitly calculate the autocorrelation function of the state vector and show how its behavior explains the phenomenon of critical slowing-down often observed for power systems on the threshold of blackout. We also estimate the collapse probability/mean clearing time for the power system and construct a new indicator function signaling the proximity to a large scale collapse. The new indicator function is easy to estimate in real time using PMU data feeds as well as SCADA information about fluctuations of power load on the nodes of the power grid. We discuss control strategies leading to the minimization of the coll...
Some Existence Theorems for Cone Saddle Points of Vector-valued Mappings%向量值映射锥鞍点存在定理
Institute of Scientific and Technical Information of China (English)
梁红卫; 张宇
2011-01-01
本文首次通过借助Kakutani-Fan-Glicksberg固定点定理和非线性标量化,研究了向量值映射的Benson锥鞍点定理.然后,通过使用该Kakutani-Fan-Glicksberg固定点定理,同样得到了集值映射的锥松鞍点定理.%In this paper,a Benson cone saddle point theorem for vector-valued mappings is first established by virtue of the Kakutani-Fan-Glicksberg fixed point theorem and a nonlinear scalarization function.Then,a cone loose saddle point theorem for set-valued mappings is also obtained by using the Kakutani-Fan-Glicksberg fixed point theorem.
DRAFT one year extension of the short-term national product waiver for stainless steel nuts and bolts used in pipe couplings, restraints, joints, flanges and saddles for State Revolving Fund projects.
Fu, Chunjiang; Suzuki, Yasuyuki; Kiyono, Ken; Morasso, Pietro; Nomura, Taishin
2014-12-06
Stability of human gait is the ability to maintain upright posture during walking against external perturbations. It is a complex process determined by a number of cross-related factors, including gait trajectory, joint impedance and neural control strategies. Here, we consider a control strategy that can achieve stable steady-state periodic gait while maintaining joint flexibility with the lowest possible joint impedance. To this end, we carried out a simulation study of a heel-toe footed biped model with hip, knee and ankle joints and a heavy head-arms-trunk element, working in the sagittal plane. For simplicity, the model assumes a periodic desired joint angle trajectory and joint torques generated by a set of feed-forward and proportional-derivative feedback controllers, whereby the joint impedance is parametrized by the feedback gains. We could show that a desired steady-state gait accompanied by the desired joint angle trajectory can be established as a stable limit cycle (LC) for the feedback controller with an appropriate set of large feedback gains. Moreover, as the feedback gains are decreased for lowering the joint stiffness, stability of the LC is lost only in a few dimensions, while leaving the remaining large number of dimensions quite stable: this means that the LC becomes saddle-type, with a low-dimensional unstable manifold and a high-dimensional stable manifold. Remarkably, the unstable manifold remains of low dimensionality even when the feedback gains are decreased far below the instability point. We then developed an intermittent neural feedback controller that is activated only for short periods of time at an optimal phase of each gait stride. We characterized the robustness of this design by showing that it can better stabilize the unstable LC with small feedback gains, leading to a flexible gait, and in particular we demonstrated that such an intermittent controller performs better if it drives the state point to the stable manifold, rather
Shahroosvand, Hashem; Zakavi, Saeed; Sousaraei, Ahmad; Eskandari, Mortaza
2015-03-07
We report on the theoretical and experimental studies of the new dye-sensitized solar cells functionalized with 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin zinc(II) complexes bearing 2- and 8-bromo substituents at the β positions. In agreement with the results of TD-DFT calculations, the absorption maxima of di- and octa-brominated Zn(II) complexes, ZnTCPPBr2 and ZnTCPPBr8, exhibited large red-shift compared to that of the non-brominated free base porphyrin (H2TCPP). Furthermore, DFT calculations showed that the higher stabilization of the LUMO levels relative to the HOMO ones makes the HOMO-LUMO gap of the brominated Zn-porphyrins models smaller compared to that of the nonbrominated counterparts, which explains the red shifts of the Soret and Q bands of the brominated compounds. Solar cells containing the new saddle-shaped Zn(II) porphyrins were subjected to analysis in a photovoltaic calibration laboratory to determine their solar to electric energy conversion. In this regard, we found that the overall conversion efficiency of ZnTCPPBr8 adsorbed on TiO2 nanocrystalline films was 5 times as large as that of ZnTCPPBr2 adsorbed on the same films. The effect of the increasing number of Br groups on the photovoltaic performance of the complexes was compared to the results of computational methods using ab initio DFT molecular dynamics simulations and quantum dynamics calculations of electronic relaxation to investigate the interfacial electron transfer (IET) in TCPPBrx/TiO2-anatase nanostructures. Better IET in ZnTCPPBr8 compared to ZnTCPPBr2, and in H2TCPP was evaluated from interfacial electron transfer (IET) simulations. The IET results indicate that electron injection in ZnTCPPBr8-TiO2 (τ = 25 fs) can be up to 5 orders of magnitude faster than ZnTCPPBr2-TiO2 (τ = 125 fs). Both experimental and theoretical results demonstrate that the increase of the number of bromo-substituents at the β-pyrrole positions of the porphyrin macrocycle created a new class of
Collas, C; Fleurance, G; Cabaret, J; Martin-Rosset, W; Wimel, L; Cortet, J; Dumont, B
2014-08-01
Agroecology opens up new perspectives for the design of sustainable farming systems by using the stimulation of natural processes to reduce the inputs needed for production. In horse farming systems, the challenge is to maximize the proportion of forages in the diet, and to develop alternatives to synthetic chemical drugs for controlling gastrointestinal nematodes. Lactating saddle mares, with high nutritional requirements, are commonly supplemented with concentrates at pasture, although the influence of energy supplementation on voluntary intake, performance and immune response against parasites has not yet been quantified. In a 4-month study, 16 lactating mares experimentally infected with cyathostome larvae either received a daily supplement of barley (60% of energy requirements for lactation) or were non-supplemented. The mares were rotationally grazed on permanent pastures over three vegetation cycles. All the mares met their energy requirements and maintained their body condition score higher than 3. In both treatments, they produced foals with a satisfying growth rate (cycle 1: 1293 g/day; cycle 2: 1029 g/day; cycle 3: 559 g/day) and conformation (according to measurements of height at withers and cannon bone width at 11 months). Parasite egg excretion by mares increased in both groups during the grazing season (from 150 to 2011 epg), independently of whether they were supplemented or not. This suggests that energy supplementation did not improve mare ability to regulate parasite burden. Under unlimited herbage conditions, grass dry matter intake by supplemented mares remained stable around 22.6 g DM/kg LW per day (i.e. 13.5 kg DM/al per day), whereas non-supplemented mares increased voluntary intake from 22.6 to 28.0 g DM/kg LW per day (13.5 to 17.2 kg DM/al per day) between mid-June and the end of August. Hence total digestible dry matter intake and net energy intake did not significantly differ between supplemented and non-supplemented mares during the
Al-Hameed, Fahad M
2015-06-01
A 62-year-old woman underwent a right mastectomy with axillary node dissection for a poorly differentiated ductal carcinoma. One month later, she underwent a left nephrectomy for a renal cell carcinoma. Two weeks after, she received her first cycle of cyclophosphamide, methotrexate, and 5FU (CMF) as a part of her breast cancer treatment. We describe an unusual case of non-occlusive saddle pulmonary embolus with extensive bilateral deep vein thrombosis and severe bronchiolitis obliterans with organizing pneumonia developing simultaneously after the first CMF chemotherapy for breast cancer.
González, David; Cabello, Gustavo; Olmos, Gema; Niñoles, Carlos L
2015-01-01
Based on recent studies regarding the advantages of flapless immediate implants on the maintenance of the soft tissue architecture (especially at papillae level) in those situations where it is necessary to extract an anterior tooth, this case report describes a clinical procedure designed to replace a hopeless central incisor (2.1) showing root resorption adjacent to an implant-supported crown (1.1), whose gingival margin is 2 mm coronal regarding the hopeless tooth to be replaced. After the extraction of the hopeless tooth (2.1), a flapless immediate implant was placed. The implant-bone gap was then filled with bone substitute and a palatal connective tissue graft was placed ad modum saddle extending at buccal level from apical to the mucogingival line, sealing the socket and extending until 6 mm at palatal level ad modum saddle. This procedure allowed symmetry of the soft tissue margins between the two implants (1.1 and 2.1) to be obtained as well as the preservation of the inter-implant papillae (1.1).
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El Aroudi A.
2014-01-01
Full Text Available In this paper closed-form conditions for predicting the boundary of period-doubling (PD bifurcation or saddle-node (SN bifurcation in a class of PWM piecewise linear systems are obtained from a time-domain asymptotic approach. Examples of switched system considered in this study are switching dc-dc power electronics converters, temperature control systems and hydraulic valve control systems among others. These conditions are obtained from the steady-state discrete-time model using an asymptotic approach without resorting to frequency-domain Fourier analysis and without using the monodromy or the Jacobian matrix of the discrete-time model as it was recently reported in the existing literature on this topic. The availability of such design-oriented boundary expressions allows to understand the effect of the different parameters of the system upon its stability and its dynamical behavior.
Rehabilitative treatment after reconstruction using saddle prosthesis%马鞍形人工半骨盆重建及术后康复治疗
Institute of Scientific and Technical Information of China (English)
张宏其; 廖前德; 周江南; 龙文荣
2004-01-01
BACKGROUND: Reconstruction using saddle prosthesis, which was developed on the basis of treating the tremendous defect of acetabulum, has recently been used to treat tumor of the pelvis by foreign researchers with remarkable curative effects.OBJECTIVE: To explore the method and results of rehabilitative treatment after semipelvic reconstruction using saddle prosthesis.DESIGN: Nonrandomized and uncontrolled study according to the diagnosis.SETTING and PARTICHANTS: The study was completed in the Department of Orthopedics, Xiangya Hospital of Central South University. A 17year-old male patient, who was diagnosed as ahvinggiant cell tumor (grade Ⅱ)in the right pelvic, was studied.INTERVENTION: Semipelvic resection (hemipelvectomy)was performed on the right side due to giant cell tumor of bone, type Ⅱ + Ⅲ, which was classified according to the system of Eneking and Dunham. Meanwhile, semipelvic reconstruction was performed using saddle prosthesis. During the immediate inpatient period, the patient was instructed to carry out phasic and progressive rehabilitation training, including initiatively moving his ankle, knee, and hip joints of the affected extremity after operation, and to adjust his gait. According to the Aboulafia AJ' S criteria for grading overall results of patients, the patients' data of ambulatory revovery were recorded.MAIN OUTCOME MEASURES: The patient's data of ambulatory recovery were recorded.RESULTS: The patient felt no pain and could perform outdoor activities without the aid of cane. The atrophica muscle on thigh of affeted extremity was improved and the results were excellent.CONCLUSION: This preliminary report demonstrates that our phasic and initiative rehabilitation training can be recommended, with favorable results,to patients who received reconstruction using saddle prosthesis due to giant cell tumor of pelvis.%背景:马鞍形人工半骨盆重建术是在治疗髋臼巨大缺损的基础上发展而来的,近年来,国外学者将
Martin, P; Cheze, L; Pourcelot, P; Desquilbet, L; Duray, L; Chateau, H
2016-05-03
Knowledge about the horse-saddle-rider interaction remains limited. The aim of this study was to compare the effect of the rider׳s position at rising trot on the pressure distribution, spine movements, stirrups forces and locomotion of the horse. The horse׳s back movements were measured using IMUs fixed at the levels of thoracic (T6, T12, T16) and lumbar (L2, L5) vertebrae, the pressure distribution using a pressure mat and stirrups forces using force sensors. The horse׳s and rider׳s approximated centres of mass (COM) were calculated using 2D reflective markers. To compare both trot phases (rider seated/rider standing), three horses were trotted at the rising trot by the same rider. Means±SD of each parameter for sitting and standing were compared using a Student׳s t test (p=0.05). Stirrups forces showed two peaks of equal magnitude in every stride cycle for left and right stirrups but increased during the standing phase. Simultaneously, the pressure for the whole mat significantly increased by +3.1kPa during the sitting phase with respect to standing phase. The T12-T16 and T16-L2 angular ranges of motion (ROM) were significantly reduced (-3.2° -1.2°) and the T6-T12 and L2-L5 ROM were significantly increased (+1.7° +0.7°) during sitting phase compared to standing phase. During rising trot, the sitting phase does not only increase the pressure on the horse׳s back but also reduces the back motion under the saddle compared to the standing phase. These results give new insights into the understanding of horse-rider interactions and equine back pain management.
Institute of Scientific and Technical Information of China (English)
Hamid Ahmadi; Mohammad Ali Lotfollahi-Yaghin; Mohammad H. Aminfar
2012-01-01
A set of parametric stress analyses was carried out for two-planar tubular DKT-joints under different axial loading conditions.The analysis results were used to present general remarks on the effects of the geometrical parameters on stress concentration factors (SCFs) at the inner saddle,outer saddle,and crown positions on the central brace.Based on results of finite element (FE) analysis and through nonlinear regression analysis,a new set of SCF parametric equations was established for fatigue design purposes.An assessment study of equations was conducted against the experimental data and original SCF database.The satisfaction of acceptance criteria proposed by the UK Department of Energy (UK DoE) was also checked.Results of parametric study showed that highly remarkable differences exist between the SCF values in a multi-planar DKT-joint and the corresponding SCFs in an equivalent uni-planar KT-joint having the same geometrical properties.It can be clearly concluded from this observation that using the equations proposed for uni-planar KT-connections to compute the SCFs in multi-planar DKT-joints will lead to either considerably under-predicting or over-predicting results.Hence,it is necessary to develop SCF formulae specially designed for multi-planar DKT-joints.Good results of equation assessment according to UK DoE acceptance criteria,high values of correlation coefficients,and the satisfactory agreement between the predictions of the proposed equations and the experimental data guarantee the accuracy of the equations.Therefore,the developed equations can be reliably used for fatigue design of offshore structures.
Mauksch, M; Schleyer, P R
2001-04-09
The topomerization mechanisms of the SF(4) and SCl(2)F(2) sulfuranes, as well as their higher (SeF(4), TeF(4)) and isoelectronic analogues PF(4)(-), AsF(4)(-), SbF(4)(-), SbCl(4)(-), ClF(4)(+), BrF(4)(+), BrCl(2)F(2)(+), and IF(4)(+)), have been computed at B3LYP/6-31+G and at B3LYP/6-311+G. All species have trigonal bipyramidal (TBP) C(2)(v)() ground states. In such four-coordinated molecules, Berry rotation exchanges both axial with two equatorial ligands simultaneously while the alternative "lever" mechanism exchanges only one axial ligand with one equatorial ligand. While the barrier for the lever exchange in SF(4) (18.8 kcal mol(-1)) is much higher than that for the Berry process (8.1 kcal mol(-1)), both mechanisms are needed for complete ligand exchange. The F(ax)F(ax) and F(eq)F(eq) isomers of SF(2)Cl(2) have nearly the same energy and readily interconvert by BPR with a barrier of 7.6 kcal mol(-1). The enantiomerization of the F(ax)F(eq) chiral isomer can occur by either the Berry process (transition state barrier 8.3 kcal mol(-1)) or the "lever" mechanism via either of two C(s)() transition states, based on the TBP geometry: Cl(ax) Cl(eq) or F(ax) F(eq) exchanges with barriers of 6.3 and 15.7 kcal mol(-1), respectively. Full scrambling of all ligand sites is possible only by inclusion of the lever mechanism. Planar, "tetrahedral", and triplet forms are much higher in energy. The TBP C(3)(v) structures of AX(4) either have two imaginary frequencies (NIMAG = 2) for the X = F, Cl species or are minima (NIMAG = 0) for the X = Br, I compounds. These "effective monkey saddle points" have degenerate modes with two small frequencies, imaginary or real. Although a strictly defined "monkey saddle" (with degenerate frequencies exactly zero) is not allowed, the flat C(3)(v) symmetry region serves as a "transition state" for trifurcation of the pathways. The BPR mechanism also is preferred over the alternative lever process in the topomerization of the selenurane SeF(4
Institute of Scientific and Technical Information of China (English)
李建慧; 李爱群; 袁辉辉; 李喜平
2009-01-01
以南京江心洲大桥为工程背景,对空间缆索自锚式悬索桥主鞍座的相关问题进行研究.以大型通用有限元程序为平台,采用二次开发技术,建立精细化有限元模型,在此基础上采用合理的加载模式对其进行空间受力分析,并阐述与空间主鞍座相匹配的主缆切点简化修正方法.结果表明:空间主缆在成桥状态对主鞍座横向力的作用会造成鞍槽外侧壁应力大于内侧壁的应力;主缆横向体积力会对主鞍座压紧装置和鞍体产生梯度分布的竖向挤压力;自锚式悬索桥体系转换过程中缆索的几何非线性效应显著,体现在空缆到成桥状态主缆与主鞍座空间切点位置会有较大的变化.%Based on the Jianxinzhou Bridge in Nanjing, the issues related to the main saddle of the serf-anchored suspension bridge with spatial cables were studied. Refinement finite element model was established with secondary development technology based on the platform of general finite element program, reasonable load pattern was used for its spatial mechanical analysis, and the spatial main cable tangenty point correction method which matched with the main saddle was also discussed. The result shows that (1) external lateral wall stress of saddle groove is higher than the internal wall stress because of the role of lateral force from the main cable in the ～mished bridge state; (2) horizontal volume force of the main cable can generate a gradient distribution of vertical extrusion pressure on the saddle clamping device and the main saddle body; (3) the geometric nonlinear effect of self-anchored suspension bridge cable system in the constroction process is significant, which reflects from that the spatial tangent point position of main cable with main saddle changes a lot from free cable to finished cable state.
Mak, Kin Fai; He, Keliang; Petrone, Nick; Hone, Jim; Shan, Jie; Heinz, Tony
2012-02-01
Significant excitonic effects were recently identified in the optical response of graphene through the asymmetric resonance feature at 4.62 eV in the optical conductivity. The peak, which is red-shifted by nearly 600 meV from the predicted band-to-band transition energy,ootnotetextMak et al. Phys. Rev. Lett. 106, 046401, (2011). can be considered as a saddle-point exciton. Here we report a systematic study of this excitonic feature as a function of the doping density, for densities extending up to the metallic regimeootnotetextEfetov & Kim, Phys. Rev. Lett. 105, 256805, (2010). (˜ 10^14 cm-2). With increasing density of either electrons or holes, the excitonic resonance is found to shift to the red and to become more symmetric in form. These experimental features agree very well with a recent ab-initio GW-Bethe-Salpeter calculationootnotetextFelipe H. da Jornada, J. D., Steven G. Louie. Private communications. (2011). and can be understood as a consequence of enhanced ``metallic'' screening of the graphene dielectric function.ootnotetextHwang, E. H. & Das Sarma, S. Phys. Rev. B 75, 205418 In addition, analysis of the width of the excitonic peak provides information on the quasiparticle lifetime. Mechanisms for the inferred rapid quasiparticle decoherence will be discussed.
Institute of Scientific and Technical Information of China (English)
李彩萍; 李宏涛
2001-01-01
在弱有效意义下建立了集值函数鞍点元存在的非导数型Kuhn-Tucker条件，并证明了这一条件的充分性。%The Kuhn-Tucker condition without derivative for the existence of a saddle point element of a set-valued function is established, and their sufficience is proved.
Institute of Scientific and Technical Information of China (English)
熊劲松; 高兴宝
2015-01-01
This paper proposes preconditioned modified AHSS method for a class of complex singular saddle point problems. It studies the semi-convergence of the proposed new method. For any positive iteration parameters, it obtains the semi-convergence theorems of the proposed new method. Nnumerical experiments show that the effectiveness of the algorithm outperforms the HSS method.%提出了求解一类复奇异鞍点问题的预条件修正AHSS法。研究了所提出的新方法的半收敛性。对任意的正迭代参数，得到了所提出的新方法的半收敛定理。数值实验说明，新方法比HSS法求解鞍点问题时更有效。
Parametric modeling and shape optimization of hybrid saddle reticulated shell%杂交型马鞍网壳结构参数化设计及形状优化
Institute of Scientific and Technical Information of China (English)
苏亚; 鹿少博; 鹿晓阳; 洪宁; 陈亚若; 李涛
2016-01-01
杂交型网壳可以发挥各单一传统网壳的优点,在增大跨度的同时又可获得较高的经济效益.文章根据杂交型马鞍型网壳结构特点,采用APDL参数化设计语言研制了两类六种不同杂交型马鞍网壳参数化设计宏程序,运用ANSYS软件对其进行受力性能分析,并对受力性能最好的凯威特—联方(Kie-Lam)网壳进行了108种工况形状优化设计.结果表明:在同等工况下六种杂交型马鞍网壳中Kie-Lam最大位移为6.9 mm和最不应力为25.1 MPa均最小,受力最为合理;矢高f与网壳最不利应力成反比,f每增加1 m最不利应力平均下降幅度最大为0.51 MPa,随Ns变化没有统一规律;在S=60 m、f=30 m不变的情况下,存在一种工况Kn=8、Nx=12和Ns=8满足结构强度、刚度和稳定性前提下,使网壳结构总耗钢量最轻.%Hybrid shell can take the advantages of each single traditional shell,which can not only increase the span but also obtain higher economic benefits at the same time. Macro program of six kinds hybrid saddle reticulated shell parametric design were developed by ANSYS parameter of design language according to saddle reticulated shell features. The mechanical performances were analyzed and the shape optimization under 108 kinds of working condition for Kiewitt-Lamella Saddle Reticulated Shell was studied with objective function of minimum steel consumption and shape optimization design variables Kn( ring to symmetric regional copies number ),Nx( radial node ring number),Ns( the upper structure of radial ring). The results showed:The maximal displacement and the most unfavorable stress of Kiewitt-Lamella were 6. 9 mm and 25. 1 Mpa,which were the least of six kinds hybrid saddle reticulated shell that its mechanical performance was the most reasonable under the same condition. The vector height f was inversely proportional to the most unfavorable stress,existing suitable f made their respective overall deflection minimum,and Ns
Institute of Scientific and Technical Information of China (English)
苏晓春; 李文涛; 郭斌; 朱明明; 杨忱
2015-01-01
文章运用 HyperWorks 有限元分析方法，通过对四种牵引车型车架鞍座连接板连接方式建立分析模型，分别在静态垂向、转弯、扭转和制动四种工况下进行虚拟仿真计算，得到车架总成在各种方案下的受力情况，为车架结构的设计提供了理论依据。%In the thesis,four kinds of model of tractor frame connected to saddle is created based on HyperWorks for strength discuss.Conditions of the frame in static,turning, torsion and braking is defined.The result of strength discuss promote the frame design.
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Thuraganur Kapanigowda
2016-06-01
Full Text Available AIMS AND OBJECTIVES Saddle block anaesthesia is most commonly used technique for perineal surgeries, i.e. haemorrhoids, fissure-in-ano, etc., as it is most economical and easy to administer. Spinal anaesthesia by bupivacaine may be too short for providing postoperative analgesia. Hence, various adjuvants have been used with Local anaesthetics to provide good intraoperative anaesthesia and to prolong postoperative analgesia. The aim of our study was to evaluate the effects of intrathecal administration of dexmedetomidine 10 µg on low dose bupivacaine 0.5% (5 mg, to know the onset and duration of sensory and motor blockade, the haemodynamic effects, duration of analgesia and the occurrence of side effects. METHODOLOGY This prospective randomized double blind study included 60 patients. Patients were randomly allocated into two groups of 30 patients each. Group D received 5 mg of 0.5% hyperbaric with dexmedetomidine 10 µg (0.5 mL and Group N received 5 mg of 0.5% hyperbaric bupivacaine with 0.5 mL of normal saline. The onset of sensory and motor block, haemodynamic effects, duration of analgesia and occurrence of side effects were noted. RESULTS The mean time taken for the onset of sensory block was 6.36±1.2 min and 8.23±1.7 significantly rapid with D Group compared to group N. The total duration of analgesia (360±15 min and 210±30 min in Group D and Group N respectively, P <0.000 and time to first rescue analgesic (370.85±15 min, 230.8±15 min in Group D and Group N respectively, P <0.001 were increased significantly by addition of dexmedetomidine without significant motor block and with minimal side effects. CONCLUSION Dexmedetomidine added intrathecally for saddle block had favourable effects on onset of sensory and total duration of analgesia and rescue analgesia.
Institute of Scientific and Technical Information of China (English)
戴睿武; 陈莉萍; 何发群; 汪涛; 薛刚; 曹永宽; 汤礼军
2009-01-01
Objective To assess the therapeutic efficacy of the prolene hernia system ( PHS) in the tension-free repair of inguinal saddle hernia.Methods41 patients using PHS were selected as subjects of this study.Results All patients received operation under local anesthesia, which lasted from 35 minutes to 60 minutes . They were kept in wards for attending from 24 hours to 72 hours. No scrotal swelling, hematoma, and incisional wound infection happened after the operation. Follow-up visits had been lasted from 6 to 42 months , and none of the patients had a relapse or the sensation of foreign body.ConclusionPHS is safe and effective in the tension-free repair, and it is suitable for inguinal saddle hernia. The successful operation lies in operative skills.%目的 探讨PHS在腹股沟马鞍疝无张力修补术中的治疗效果和手术经验.方法 对41例使用PHS行无张力修补术的腹股沟马鞍疝患者进行分析.结果 在局麻下完成手术,手术时间25~60 min,全组留院观察24~72 h,无阴囊积液、切口感染、血肿及其它与手术有关的并发症.随访6~42个月,无复发,无异物感.结论 PHS修补牢靠,对于腹股沟马鞍疝的手术治疗更有针对性.重视手术的技巧是手术成功的关键.
Institute of Scientific and Technical Information of China (English)
张国虎; 薛刚; 龚加庆; 田伏洲
2007-01-01
目的 探讨PHS在腹股沟马鞍疝无张力修补术中的治疗效果和手术经验.方法 对11例使用PHS行无张力修补术的腹股沟马鞍疝患者进行分析.结果 在局麻下完成手术,手术时间25～60 min,全组留院观察24～72 h,无阴囊积液、切口感染、血肿及其它与手术有关的并发症.随访6个月～30个月,无复发,无异物感.结论 PHS修补牢靠,对于腹股沟马鞍疝的手术治疗更有针对性.重视手术的技巧是手术成功的关键.%Objective To assess the prolene hernia system ( PHS) in tension-free repair of inguinal saddle hernia. Methods Eleven cases using PHS were studied. Results All patients were underwent the operation under local anesthesia, and the operation lasted for 35 to 60 minutes . They were monitored in wards for 24 to 72 hours. No scrotal swelling, hematoma, and wound infection happened after the operation. Follow-up lasted for 6 to 30 months , and none of the patients relapsed or had a sensation of foreign body. Conclusion PHS is safe and effective in tension-free repair of hernia, and it is fit to repair of inguinal saddle hernia.
Institute of Scientific and Technical Information of China (English)
文开庭
2008-01-01
In this paper,a new fixed point theorem is established in noncompact hyperconvex metric spaces.As applications,a continuous selection and its fixed point theorem,an existence theorem for maximal elements,a Ky Fan minimax inequality and an existence theorem for saddle points are obtained.
Directory of Open Access Journals (Sweden)
Eryca Vanessa S. de Jesus
2010-09-01
extras a la homeostasis cardiovascular en la presencia del síndrome coronario aguda (SCA OBJETIVO: Investigar si un diagnóstico clínico estandarizado de SAOS, en pacientes con SCA, predice el riesgo de eventos cardiovasculares durante la hospitalización. MÉTODOS: En un estudio de cohorte prospectivo, un grupo de 200 pacientes con diagnóstico de SCA elecido entre Septiembre de 2005 y Noviembre de 2007, fueron estratificados por el Cuestionario de Berlín (CB para el riesgo de SAOS (alto o bajo riesgo. Se probó si el subgrupo de alto riesgo para SAOS presenta mayor tendencia a eventos cardiovasculares. El endpoint primario evaluado fue un desenlace conformado por muerte cardiovascular, eventos cardíacos isquémicos recurrentes, edema pulmonar agudo y accidente vascular cerebral durante la hospitalización. RESULTADOS: Noventa y cuatro (47% de los pacientes identificados por el CB presentaban sospecha de SAOS. Alto riesgo para SAOS estaba asociado con una mortalidad más elevada, aunque sin diferencia estadística (4,25% vs 0,94%; p=0,189, pero con una estadísticamente significativa mayor incidencia de desenlace conformada por eventos cardiovasculares (18,08% vs 6,6%; p=0,016. En el modelo de regresión logística, los predictores multivariados de desenlace conformado por eventos cardiovasculares fueron edad (OR= 1,048; IC95%: 1,008 a 1,090; p=0,019, fracción de eyección del VI (OR= 0,954; IC95%: 0,920 a 0,989; p=0,010, y riesgo más elevado de SAOS (OR= 3,657; IC95%: 1,216 a 10,996; p=0,021. CONCLUSIÓN: El uso de un cuestionario sencillo y validado (CB para identificar a pacientes con riesgo más elevado de SAOS puede ayudar a prever el desenlace cardiovascular durante la hospitalización. Además de ello, nuestros datos sugieren que SAOS es mucho común en pacientes con SCA.BACKGROUND: From a mechanistic standpoint, obstructive sleep apnea (OSA may further disturb cardiovascular homeostasis in the setting of acute coronary syndrome (ACS. OBJECTIVE: We sought
Institute of Scientific and Technical Information of China (English)
郑源; 茅媛婷; 周大庆; 张单
2011-01-01
运用数值模拟与模型试验相结合的方法,采用计算流体动力学软件Fluent,在双参考坐标系下,利用有限体积法对雷诺时均Navier-Stokes方程进行数值离散,选用标准k-ε湍流模型,SIMPLEC方法求解,对轴流泵模型装置20％～130％额定流量工况点的外特性进行了数值模拟,并将计算结果与模型试验结果进行对比.通过对设计工况和小流量马鞍区工况下CFD流态图样的对比分析,对马鞍区的流动特性进行了研究.结果表明:在50％～65％设计流量区域存在轴流泵的运行不稳定马鞍区;小流量工况下泵室内转轮进出口均存在大范围的回流和旋涡,激烈的能量交换是轴流泵出现不稳定区、装置无法稳定运行的主要原因；数值模拟与模型试验结果吻合较好,整体误差不超过5％,由此证明了数值模拟的有效性和准确性.%Numerical and experimental methods were applied to investigate the axial pump flow characteristics in the saddle zone. The standard k-e turbulence model and SIMPLEC algorithm were chosen in computation fluid dynamics software Fluent, the Reynolds-averaged Navier-Stokes equation was dispersed by the finite volume method, and external characteristics of axial pump model were numerical simulated in a test facility from 20% to 130% of designed flow rate. The results between numerical calculation and model experiment were compared. Flow characteristics in saddle zone were studied by comparing flow patterns between designed condition and small flow rate condition. The results show that unsteady operation saddle zone exists between 50% of designed flow rate and 65% of designed flow rate. Large range recirculation and vortex exist at the inlet and outlet of the impeller under small flow rate condition. Intensive power-exchange is the main cause of the pump unstable operation. The results of three dimensions CFD simulation and test results agree well near the best efficiency point, and
Institute of Scientific and Technical Information of China (English)
钱忠东; 王凡; 王志远; 周皖
2013-01-01
In order to analyze the effects of adjustable guide vane (AGV) on axial pumps working in saddle zone,in the hope of optimizing adjusting laws,performance test of a new axial-flow pump with AGV was carried out on the pump test bed.Q-H,Q-ηand Q-P curves at different guide vane angles were obtained.The effects of AGV on hydraulic performance of the model pump in saddle zone were analyzed.The results show that,at the same flow rate,head and efficiency of axial flow pump increase as guide vane angle is adjusted from 0° to-5°.With AGV,the separation vortex in the flow channel is suppressed effectively; flow regime at pump outlet is optimized obviously; kinetic energy recovery rate is improved.Head and efficiency of the pump are improved by 0.15 m (0.046 9Hd) and 1.93％ respectively.The critical flow discharge is decreased by 0.004 94 m3/s and the range of saddle-shaped zone is narrowed by 6.64％,broadening the range of stable working zone.At guide vane angle of-5°-0°,the shaft power changes little.In this experiment,the best values of hydraulic performance obtained are at-5° guide vane angle,but they can be further improved.%为了分析不同导叶安放角对轴流泵在马鞍区工况运行时的影响,探究导叶角度的优化规律,在水泵模型试验台上,对一种新型可调导叶式轴流泵的外特性进行测试,得到不同导叶安放角下H-Q、η-Q、P-Q曲线,分析了导叶安放角对轴流泵马鞍区水力特性的影响.试验结果表明:相同流量工况下轴流泵的扬程和效率随着导叶安放角由0°向-5 °调节而增大,调节导叶安放角,能够有效抑制叶片背面脱流旋涡的扩散,显著改善轴流泵出口的流态,提高动能回收的比例；在马鞍区工况下,扬程最大提升0.15m,为设计扬程的4.69％,效率最大提升1.93％；马鞍区起始点流量向小流量偏移了0.004 94 m3/s,马鞍区范围减小了6.64％,拓宽了轴流泵稳定运行的区域；导叶安放角在-5°～0°的
Institute of Scientific and Technical Information of China (English)
程浩南
2015-01-01
Although the saddle method is one of the standards for fabric bending performance test ,but the process has not issued up to now. This paper made a saddle shaped fabric bending device by learning the existing test methods of fabric bending performance deeply. The maximum bending force FM and the bending hysteres A are two test index in this paper. Through the design of orthogonal test, this paper studied the changes of the maximum bending force FM and the bending hysteres A to obtain optimal experiment scheme under the different experimental parameters. This paper took the data of the maximum bending force FM and the bending hysteres A to make a linear correlation .with the data of the average bending stiffness B and the average bending hysteresis 2HB took from the KES style instrument. The results showed that:the correlation coefficient of FM and B is 0.982,the correlation coefficient of A and 2HB is 0.982, so This test method is effective.%马鞍法是国标中测试织物弯曲性能的一种方法，虽然被写进国标当中，但是具体测试方法过程至今没有发布。为了探讨基于马鞍法对织物弯曲性能进行测试的有效性，本文研究现有织物弯曲性能测试方法的基础上，自制一套马鞍状织物弯曲的装置，将最大抗弯曲力FM和弯曲迟滞A作为测试指标，分别与KES风格仪测试指标中的平均弯曲刚度B和平均弯曲滞后量2HB进行线性相关性分析，结果表明：FM与B的相关系数为0.982， A与2HB的相关系数为0.907，进而验证了基于马鞍法对织物弯曲性能进行测试的有效性。
Institute of Scientific and Technical Information of China (English)
吴明亮; 杨东方
2013-01-01
The detail design scheme of CNC system based on MSC-51 SCM was put forward for the saddle surface of flange connection processing plant. The manufacturing plan, the hardware circuit and software flowchart were discussed. C language and assemble language were used to program in uVision2. Hardware circuit was designed in Protues7. The simulation results show that the proposed design scheme of the CNC system is feasible.%针对法兰接管马鞍曲面加工专机,提出一种基于51系列单片机的CNC系统设计方案.详细阐述了加工方案,并给出硬件电路的构成方案和软件的程序流程图.利用C语言和汇编语言在uVision2下进行混合编程,并在Protues7中完成硬件电路设计,进行了联合仿真验证.结果表明:自主开发的数控系统能够满足法兰接管的加工要求.
Institute of Scientific and Technical Information of China (English)
文开庭
2008-01-01
In this paper, the generalized metric S-KKM mapping and the hyper S-γ-generalized quasi-convex (resp., concave) functional arc introduced when S is a set-valued mapping, the generalized metric S-KKM mapping principle is obtained, and the relation between the generalized metric S-KKM mapping and the hyper S-γ-generalized quasi-convex (resp., concave) functional is established. As application, the new Ky Fan minimax inequality and the new existence theorem for saddle points are obtained in hyperconvex metric spaces.%引入了S为集值映射情况下的广义度量S-KKM映射和超S-γ-广义拟凸(凹)函数,建立了广义度量S-KKM映射原理和广义度量S-KKM映射与超S-γ-广义拟凸(凹)函数的关系,作为应用,获得了超凸度量空间中的新的Ky Fan极大极小不等式和鞍点定理.
Wang, Xiaohong; Bowman, Joel M
2013-02-12
We calculate the probabilities for the association reactions H+HCN→H2CN* and cis/trans-HCNH*, using quasiclassical trajectory (QCT) and classical trajectory (CT) calculations, on a new global ab initio potential energy surface (PES) for H2CN including the reaction channels. The surface is a linear least-squares fit of roughly 60 000 CCSD(T)-F12b/aug-cc-pVDZ electronic energies, using a permutationally invariant basis with Morse-type variables. The reaction probabilities are obtained at a variety of collision energies and impact parameters. Large differences in the threshold energies in the two types of dynamics calculations are traced to the absence of zero-point energy in the CT calculations. We argue that the QCT threshold energy is the realistic one. In addition, trajectories find a direct pathway to trans-HCNH, even though there is no obvious transition state (TS) for this pathway. Instead the saddle point (SP) for the addition to cis-HCNH is evidently also the TS for direct formation of trans-HCNH.
Energy Technology Data Exchange (ETDEWEB)
Jangi, M.S.; Ibrahim, H. (Faculty of Health Sciences, Universiti Kebangsaan, Malysia, Bangi, Selangor)
1983-05-01
A total of 24 isolates of Bacillus thuringiensis (Berliner), resistant to a ..gamma..-radiation dose of 100 krad, were screened for their toxicity to larval silkworms, Bombyxmori(L.), and 15 of them were subsequently tested for their toxicity to larval diamond-back moth, Plutella xylostella(L.). The LC/sub 50/'s of these isolates to B. mori ranged from 1.6 X 10/sup 5/ to 6.0 X 10/sup 3/ spores/mL or from 5.9 to 0.3 ..mu..g cellular protein/mL. The irradiation treatment produced isolates which were significantly more toxic to P. xylostella (LC/sub 50/ < 8.1 X 10/sup 4/ spores/mL or 3.7 ..mu..g cellular protein/mL) and/ or less toxic to B. mori (LC/sub 50/ > 2.3 X 10/sup 4/ spores/mL or 1.0 ..mu..g cellular protein/mL) than the parent commercial strain.
Huertos urbanos en tres ciudades europeas: Londres, Berlín, Madrid
Morán Alonso, Nerea
2014-01-01
En el momento actual de crisis ecológica son necesarios nuevos procesos de recuperación del espacio urbano que mejoren la sostenibilidad integral de las ciudades, tanto a nivel ambiental como relacional. Los huertos urbanos son instrumentos que responden a este requerimiento, pues colaboran en el cierre de ciclos del metabolismo urbano y proporcionan una mayor calidad de vida a los ciudadanos.En el presente trabajo se intenta encontrar las condiciones legales y normativas más favorables para ...
Zhang, Zhiyun; Wu, Yu-Sin; Tang, Kuo-Chun; Chen, Chi-Lin; Ho, Jr-Wei; Su, Jianhua; Tian, He; Chou, Pi-Tai
2015-07-08
A tailored strategy is utilized to modify 5,10-dimethylphenazine (DMP) to donor-acceptor type N,N'-disubstituted-dihydrodibenzo[a,c]phenazines. The representative compounds DMAC (N,N'-dimethyl), DPAC (N,N'-diphenyl), and FlPAC (N-phenyl-N'-fluorenyl) reveal significant nonplanar distortions (i.e., a saddle shape) and remarkably large Stokes-shifted emission independent of the solvent polarity. For DPAC and FlPAC with higher steric hindrance on the N,N'-substituents, normal Stokes-shifted emission also appears, for which the peak wavelength reveals solvent-polarity dependence. These unique photophysical behaviors are rationalized by electronic configuration coupled conformation changes en route to the geometry planarization in the excited state. This proposed mechanism is different from the symmetry rule imposed to explain the anomalously long-wavelength emission for DMP and is firmly supported by polarity-, viscosity-, and temperature-dependent steady-state and nanosecond time-resolved spectroscopy. Together with femtosecond early dynamics and computational simulation of the reaction energy surfaces, the results lead us to establish a sequential, three-step kinetics. Upon electronic excitation of N,N'-disubstituted-dihydrodibenzo[a,c]phenazines, intramolecular charge-transfer takes place, followed by the combination of polarization stabilization and skeletal motion toward the planarization, i.e., elongation of the π-delocalization over the benzo[a,c]phenazines moiety. Along the planarization, DPAC and FlPAC encounter steric hindrance raised by the N,N'-disubstitutes, resulting in a local minimum state, i.e., the intermediate. The combination of initial charge-transfer state, intermediate, and the final planarization state renders the full spectrum of interest and significance in their anomalous photophysics. Depending on rigidity, the N,N'-disubstituted-dihydrodibenzo[a,c]phenazines exhibit multiple emissions, which can be widely tuned from red to deep blue and
Topological equivalence for multiple saddle connections
Directory of Open Access Journals (Sweden)
CLEMENTA ALONSO
2002-12-01
Full Text Available We study the topological equivalence between two vector fields defined in the neighborhood of the skeleton of a normal crossings divisor in an ambient space of dimension three. We deal with singularities obtained from local ones by ambient blowing-ups: we impose thus the non-degeneracy condition that they are all hyperbolic without certain algebraic resonances in the set of eigenvalues. Once we cut-out the attractors, we get the result if the corresponding graph has no cycles. The case of cycles is of another nature, as the Dulac Problem in dimension three.Estudamos a equivalência topológica entre dois campos de vetores na vizinhança do esqueleto de um divisor com cruzamento normal, num ambiente de dimensão três. Consideramos singularidades obtidas por explosões a partir de uma singularidade local: isto justifica a condição de hiperbolicidade e não ressonância no conjunto dos autovalores. O resultado principal se obtém quando, depois de retirar os atratores, o grafo resultante não tem ciclos. O caso dos ciclos é de natureza semelhante ao problema de Dulac em dimensão três.
Sphalerons and other saddles from cooling
García-Pérez, M; Margarita Garcia Perez; Pierre van Baal
1994-01-01
We describe a new cooling algorithm for SU(2) lattice gauge theory. It has any critical point of the energy or action functional as a fixed point. In particular, any number of unstable modes may occur. We also provide insight in the convergence of the cooling algorithms. A number of solutions will be discussed, in particular the sphalerons for twisted and periodic boundary conditions which are important for the low-energy dynamics of gauge theories. For a unit cubic volume we find a sphaleron energy of resp. \\cE_s=34.148(2) and \\cE_s=72.605(2) for the twisted and periodic case. Remarkably, the magnetic field for the periodic sphaleron satisfies at all points \\Tr B_x^2=\\Tr B_y^2=\\Tr B_z^2.
Searching chaotic saddles in high dimensions
Sala, M; Altmann, E G
2016-01-01
We propose new methods to numerically approximate non-attracting sets governing transiently-chaotic systems. Trajectories starting in a vicinity $\\Omega$ of these sets escape $\\Omega$ in a finite time $\\tau$ and the problem is to find initial conditions ${\\bf x} \\in \\Omega$ with increasingly large $\\tau= \\tau({\\bf x})$. We search points ${\\bf x}'$ with $\\tau({\\bf x}')>\\tau({\\bf x})$ in a {\\it search domain} in $\\Omega$. Our first method considers a search domain with size that decreases exponentially in $\\tau$, with an exponent proportional to the largest Lyapunov exponent $\\lambda_1$. Our second method considers anisotropic search domains in the {\\it tangent} unstable manifold, where each direction scale as the inverse of the corresponding {\\it expanding} singular value of the Jacobian matrix of the iterated map. We show that both methods outperform the state-of-the-art {\\it Stagger-and-Step} method (Sweet, Nusse, and York, Phys. Rev. Lett. {\\bf 86}, 2261, 2001) but that only the anisotropic method achieves ...
Saddle point avoidance in barrier crossing problems
Energy Technology Data Exchange (ETDEWEB)
Talkner, P.; Drozdov, A.N. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)
1997-06-01
The long-time behavior of the stochastic dynamics of a two-dimensional system having two metastable states is investigated by means of the low-lying part of the corresponding two-dimensional Smoluchowski operator. In particular, its dependence on three parameters describing the strength of the noise, the coupling of the degrees of freedom and a ratio of relaxation-times is considered. Further information characterizing the transition process between the metastable states is gained from the corresponding eigenfunctions. (author) 9 refs.
Saddle-node dynamics for edge detection
Energy Technology Data Exchange (ETDEWEB)
Wong, Y.F. [Lawrence Livermore National Lab., CA (United States). Inst. for Scientific Computing Research
1994-09-01
The author demonstrates how the formulation of a nonlinear scale-space filter can be used for edge detection and junction analysis. By casting edge-preserving filtering in terms of maximizing information content subject to an average cost function, the computed cost at each pixel location becomes a local measure of edgeness. This computation depends on a single scale parameter and the given image data. Unlike previous approaches which require careful tuning of the filter kernels for various types of edges, this scheme is general enough to be able to handle different edges, such as lines, step edges, corners and junctions. Anisotropy in the data is handled automatically by the nonlinear dynamics.
Institute of Scientific and Technical Information of China (English)
陈芳; 蒋耀林
2012-01-01
白中治等提出了解非埃尔米特正定线性方程组的埃尔米特和反埃尔米特分裂（HSS）迭代方法（BaiZZ，GolubGH，NgMK．Hermitian and skew-Hermitian splitting methods for non—Hermitian positive definite linearsystems．SIAM，Matrix Anal．Appl．，2003，24：603-626）．本文精确地估计了用HSS迭代方法求解广义鞍点问题时在加权2一范数和2一范数下的收缩因子．在实际的计算中，正是这些收缩因子而不是迭代矩阵的谱半径，本质上控制着HSS迭代方法的实际收敛速度．根据文中的分析，求解广义鞍点问题的HSS迭代方法的收缩因子在加权2．范数下等于1，在2一范数下它会大于等于1，而在某种适当选取的范数之下，它则会小于1．最后，用数值算例说明了理论结果的正确性．%The Hermitian and skew-Hermitian splitting （HSS） iteration method was presented and studied by Bai, et al. for solving non-Hermitian positive defi- nite linear systems （Bai Z Z, Golub G H, Ng M K. Hermitian and skew-Hermitian splitting methods for non-Hermitian positive definite linear systems. SIAM J. Ma- trix Anal. Appl., 2003, 24：603 626）. In this paper, contraction factors of the HSS iteration method in terms of the weighted 2-norm and the 2-norm are given, respec- tively, for the generalized saddle point problems. These contraction factors rather than the spectral radius of the iteration matrix essentially control the actual conver- gent speed of the HSS iteration method in practical computations. According to the analyses, the contraction factor of the HSS iteration method for the generalized sad- dle point problem is one in the weighted 2-norm. However, it may be greater than or equal to one in the 2-norm and less than one in other suitable norms. Finally, numerical examples are used to examine the correctness of the theoretical results.
Institute of Scientific and Technical Information of China (English)
李如源
2016-01-01
某核电厂1号机组因阀门内漏导致辅助给水系统(ASG)内30℃的水进入230℃的主给水系统(ARE)中,ARE-ASG 连接管座存在因介质温差引起的热疲劳失效风险。利用 ANSYS有限元程序对连接管座流场、温度场进行流固耦合分析,计算管座的热应力,采用程序的疲劳模块及材料疲劳曲线对连接管座的疲劳寿命进行了评估。结果表明：连接管座在内压条件下应力满足技术规范 RCC-M 的强度要求,热应力的最大值出现在管座内表面相贯线位置,其热疲劳寿命为954次。%Due to the valve leakage of unit 1,the fluid from the auxiliary feed water system (ASG)of which the temperature was about 30 ℃,entered into the main feed water system (ARE)of which the temperature was about 230 ℃. Therefore a risk of thermal fatigue failure caused by temperature difference existed in the pipe saddle of ARE-ASG.By ANSYS finite element program,fluid-structure interaction analysis was carried out on the flow field and temperature field of the pipe saddle,and the thermal stress was also calculated.The fatigue life evaluation of the pipe saddle was carried through fatigue model program and the material fatigue curve.The results show that under the internal pressure the stress of the pipe saddle could meet the requirement of the specification standard RCC-M,the maximum thermal stress existed on the intersecting part of the pipes,and the service life of thermal fatigue was 954 times.
Institute of Scientific and Technical Information of China (English)
何步斌
2015-01-01
通过对厂修货车转K6型承载鞍组装过程中常见的承载鞍推力挡肩内径面与前盖外径面间隙超限、 承载鞍与侧架导框纵向单侧间隙超限、 轴箱橡胶垫无法落位3种故障进行分析, 查找原因, 提出控制措施.%The paper analyzes the common faults of assembling the bogie load-bearing saddle typed K6 of the truck repaired in the factory from three aspects , i.e.the gap beyond the limit between the aperture surface of the thrust block shoulder and the outside diameter of the front cover , the longitudinal unilateral gap beyond the limit between the load-bearing saddle and the side guide frame and the rubber blanket of the axle box failure to reach the designated position .It aims at finding out the reason of problems and puts forward some controlling measures .
Directory of Open Access Journals (Sweden)
Matej Zorman
2008-12-01
Full Text Available Downy mildew is one of the most economically important disease affecting vine production in Terceira island, Azores. By its incidence, frequency and quantity of pathogens, supported with favourable temperate humid climate conditions, this disease is difficult to control in terms of sustainable integrated plant protection policy. The objectives of INTERFRUTA project were to determine the incidence of the disease, to better understand it and to adopt an adequate forecasting model with necessary adjustments to predict the disease appearance and its in-time integrated plant protection control measures. Plasmopara viticola was directly observed in two weeks time periods on seven representative vineyards at different altitudes. Three of the monitored plots were established during study inside one plantation. Incidence was registered as result of visual symptoms in percentage, where 10% of plants in each vineyard were observed. Seasonal evolution of the disease was studied in one of the wine producing area.O Míldio é uma das doenças que mais afecta a vinha, na ilha Terceira, Açores. É uma doença fúngica de difícil controlo, pela sua incidência e frequência de aparecimento. Os objectivos do projecto INTERFRUTA II foram determinar a incidência desta doença para melhorar o conhecimento sobre esta e adoptar e validar um modelo matemático adequado à previsão do aparecimento da doença de modo a permitir a aplicação de medidas de protecção integrada. A evolução do míldio foi acompanhada em sete parcelas de vinha, da área vitivinícola dos Biscoitos, através da observação visual de folhas. Numa das parcelas, três dos talhões não foram tratados para servirem de controlo. Em cada parcela foram observadas 10% das plantas, tendo sido registada a percentagem de plantas com sintomas visuais da presença de míldio.
Hidalgo, D; Sacco, A; Hernández, S; Tommasi, T
2015-11-01
A mixed microbial population naturally presents in seawater was used as active anodic biofilm of two Microbial Fuel Cells (MFCs), employing either a 2D commercial carbon felt or 3D carbon-coated Berl saddles as anode electrodes, with the aim to compare their electrochemical behavior under continuous operation. After an initial increase of the maximum power density, the felt-based cell reduced its performance at 5 months (from 7 to 4 μW cm(-2)), while the saddle-based MFC exceeds 9 μW cm(-2) (after 2 months) and maintained such performance for all the tests. Electrochemical impedance spectroscopy was used to identify the MFCs controlling losses and indicates that the mass-transport limitations at the biofilm-electrolyte interface have the main contribution (>95%) to their internal resistance. The activation resistance was one order of magnitude lower with the Berl saddles than with carbon felt, suggesting an enhanced charge-transfer in the high surface-area 3D electrode, due to an increase in bacteria population growth.
Institute of Scientific and Technical Information of China (English)
魏鹏飞; 吕震宙; 袁修开
2012-01-01
针对同时存在随机不确定性和模糊不确定性的可靠性分析问题,提出了两种高效解决方法。一种是迭代马尔科夫链鞍点逼近法,该方法的基本思想是给定隶属水平下由迭代马尔科夫链和一次鞍点逼近法求得可靠度上下限,不同的隶属水平对应不同的可靠度上下限,遍历隶属水平的取值区间[0,1]即可求得可靠度隶属函数,与传统的两相Monte Carlo数字模拟法和迭代一次二阶矩法相比,该方法具有效率高和对非正态基本随机变量不需要进行正态转换的优点;第二种方法是迭代条件概率马尔科夫链模拟法,该方法在求解给定隶属度水平下的可靠度上下限时,由条件概率公式引入一个非线性修正因子,该因子的引入大大提高了功能函数为非线性的可靠性问题的求解精度。本文算例验证了所提方法的优越性。%Two novel methods are developed to solve the mixed probability analysis problem with both random and f uzzy uncertainties.The first one is Iterative Markov Chain Simulation First Order Saddle-point Approximation（IMCSFOSA） whose key idea is to get the upper limit and lower limit of the reliability for a given membership level with Markov Chain and First Order Saddle-point Approximation,and throughout the whole value domain of membership level by this process,the membership function of reliability can be obtained.Compared with the traditional methods,such as double-loop Monte Carlo simulation and iterative first order and second moment method,the IMCSFOSA is more efficient due to less simulation and more effective due to no transformation from the non-normal distribution to the normal one.The second method is Iterative Conditional Probability Markov Chain Simulation（ICPMCS）,in which a nonlinear modification factor is introduced by Conditional Probability formula in solving the upper limit and lower limit of the reliability for a given membership level.The introduction
Institute of Scientific and Technical Information of China (English)
万昌涛; 明江华; 彭昊
2014-01-01
BACKGROUND:The region around the hip is a bone tumor predilection site. It is difficult to conduct tumor resection due to the involvement of weight loading area. Tumor resection requires high surgical technique. The pelvis and hip are often needed to be rebuilt. OBJECTIVE:To compare the effects of three reconstruction methods after tumor resection around the hip. METHODS:From January 2007 to December 2012, 20 patients with bone tumors around the hip were treated by surgery in the Zhongshan Hospital, Wuhan University, including 7 benign tumors, 13 borderline and malignant tumors. Eight patients received al ograft. Eight patients received arthroplasty. Four patients received saddle prosthesis. RESULTS AND CONCLUSION:A total of 20 patients were fol owed up for 5 to 60 months (averagely 40 months). According to Enneking evaluation criterion, the operative outcome was evaluated as excellent in 8 cases, good in 5 cases, average in 4 cases, and poor in 3 cases. Excellent and good rate was 65%. Results suggested that after excision of bone tumors, al ograft, arthroplasty or saddle prosthesis can significantly elevate patient’s survival rate, improve patient’s living quality and is an effective therapy for treating tumors around the hip.%背景：髋周围骨肿瘤是全身骨肿瘤好发部位，由于累及负重区，肿瘤切除难度大，对手术技术要求较高，同时往往需要重建骨盆及髋关节功能。 目的：比较髋周围骨肿瘤切除后3种不同修复重建方法的效果。 方法：收集2007年1月至2012年12月于武汉大学中山医院进行手术治疗的髋周围骨肿瘤患者20例，其中良性7例，交界性和恶性13例。均以手术切除治疗。8例采用异体骨移植，8例采用人工关节置换，4例采用鞍式假体重建。 结果与结论：20例均获得随访，随访时间5-60个月，平均40个月。根据Enneking评分标准，优8例﹑良5例﹑中4例﹑差3例，评估优良率65%
Nonconvergence to Saddle Boundary Points under Perturbed Reinforcement Learning
2012-12-07
This paper presents a novel reinforcement learning algorithm and provides conditions for global convergence to Nash equilibria. For several classes...of reinforcement learning schemes, including the ones proposed here, excluding convergence to action profiles which are not Nash equilibria may not be...perturbed reinforcement learning scheme where the strategy of each agent is perturbed by a strategy-dependent perturbation (or mutations) function
Saddled With History: Airmindedness and Its Antecedents in Union Cavalry
2014-06-01
enthusiasm were essential to weathering the early storms. His unrelenting patience was essential to weathering my procrastination and unreadable drafts...disposition toward self -discipline. This high regard for handiwork and responsibility led him to West Point where he graduated sixth out of 41...modernization programs.55 Weapons modernization was due in large part to legacy influences imposed by infantry regulations regarding weapons procurement
Bifurcation of Homoclinic Orbits with Saddle-Center Equilibrium
Institute of Scientific and Technical Information of China (English)
Xingbo LIU; Xianlong FU; Deming ZHU
2007-01-01
In this paper, the authors develop new global perturbation techniques for detecting the persistence of transversal homoclinic orbits in a more general nondegenerated system with action-angle variable. The unperturbed system is assumed to have saddlecenter type equilibrium whose stable and unstable manifolds intersect in one dimensional manifold, and does not have to be completely integrable or near-integrable. By constructing local coordinate systems near the unperturbed homoclinic orbit, the conditions of existence of transversal homoclinic orbit are obtained, and the existence of periodic orbits bifurcated from homoclinic orbit is also considered.
Factorized parallel preconditioner for the saddle point problem
DEFF Research Database (Denmark)
Lazarov, Boyan Stefanov; Sigmund, Ole
2011-01-01
The aim of this paper is to apply the factorized sparse approximate inverse (FSAI) preconditioner to the iterative solution of linear systems with indefinite symmetric matrices. Until now the FSAI technique has been applied mainly to positive definite systems and with a limited success...
Saddle and leg forces during lateral movements in dressage
Cocq, de P.; Mooren, M.; Dortmans, A.; Weeren, van P.R.; Timmermans, M.; Muller, M.; Leeuwen, van J.L.
2010-01-01
Reasons for performing study: In the equestrian world it is assumed that riders use changes in weight distribution and leg forces as important instruments to give horses directions about speed and direction of movement. However, the changes of these forces have never been quantified. Objectives: To
The Horse With Two Saddles-Tamxhwe in Modern Golok
Directory of Open Access Journals (Sweden)
Fernanda Pirie
2009-03-01
Full Text Available Thirty-three examples of oral sayings, mainly from the Golok area, used in conflict mediation are presented and discussed in terms of their usage by mediators and how they reflect Tibetan values and life. ''You have to go to Golok to hear real tamxhwe." Conflict resolution is a topic most Amdo Tibetans will readily discuss and the oratorical skills of the zowa (gzu ba 'mediators' are always emphasized. It was in Golok that they were said to be particularly impressive. ''They make displays of oratory during the early stages of the mediation process,'' explained one informant, a respected mediator from Machu (Rma chu. ''They use proverbs and riddles that are difficult to understand. It is like jousting with words, a display of skill.'' He was referring to the representatives of individual parties, but the same skills are even more important for mediators. The more serious and entrenched the conflict—two Amdo tribes may fight for generations over valuable grassland—the more important it is to secure a high-status mediator, often a lama or local leader with a reputation for oratory. The mediators' task is to persuade reluctant parties to compromise and accept compensation in lieu of taking revenge for an injury or killing; this can require a lengthy and elaborate process extending over several days. ''In Golok,'' my informant continued, ''they use tamxhwe; those who can make good speeches and employ it well enjoy high reputations.'' The tamxhwe, it appeared, were like proverbs or riddles and in one or two cases an informant was able to repeat one of them to me, but I was repeatedly told that I had to go to Golok to learn more. The oratorical skills of the Golok mediators obviously had a considerable reputation throughout Amdo, and in the summer of 2004 I went to this large area in southern Qinghai Province to investigate. ...
Cavalca, Guido
2010-01-01
La comparación entre madres solas en una ciudad prospera, Milano (Italia), y una ciudad en crisis económica y laboral, Berlin (Alemania), se dirige a descubrir si existe un modelo único de empobrecimiento urbano, o bien si la construcción social de la pobreza tiene características contextuales. El estudio de las trayectorías biográficas de madres solas ha permitido la construcción de trayectorias ideal-típicas de empobrecimiento. Nuestro trabajo de campo muestra como los procesos de empobreci...
Directory of Open Access Journals (Sweden)
Mónica Drebing Ruiz Holst
1996-01-01
Full Text Available El objetivo del presente trabajo es analizar la situacion de j6venes que estan en para o amenazados por este, asi como la importancia de la Pedagogia Social en la formación profesional de jóvenes socialmente desfavorecidos en Alemania, concretamente en Berlin. Como en otros parses industriales del oeste, la Republica Federal Alemana anota un número considerable de parados a raiz de la crisis de 1974/75 en los años 80. El número de parados ascendio a casi 2,5 millones en enero de 1983. En el misrno afio en Berlin Oeste 88 7 I9 mujcres y hombres adultos estuvieron en pam con una tasa de 11,I%. Los jovenes menores de 20 aiios alcanzaron una tasa de pam de 16,4% con 6 321 j6venes. Al considerar las estadfsticas de estos juveniles, se pucdc constatar que la mayorfa de ellos no recibieran una formaci6n profesional. A consecuencia de esta situacion extremadamente negativa para los j6venes en cuestion, la Prestacion Juvenil estatal (staatliche Jugendhil[e intenta seguir un nuevo camino al ofrecer fuera del ambito de los hogares juveniles, plazas para la formaci6n profesional con un componente socio-pedag6gico. Esto es el caso del Modelo Experimental (Modellversuch que se cre6 en Berlin Oeste en 1979. Par ultimo, se trata de reflejar la situacion actual del para y de la formación profesional para jovenes socialmente desfavorecidos en Berlin.
De la Diosa Fortuna al Ángel de la Victoria en el Berlín del siglo XIX. Homenaje a Yolanda Ruano
González García, José M.
2010-01-01
Este artículo de homenaje a la Profesora Yolanda Ruano se divide en dos partes. En la primera discuto las críticas que ella realizara a mi libro sobre la diosa Fortuna en las que avanzaba su propio análisis de las complejas relaciones entre razón y fortuna en el pensamiento occidental. En la segunda parte, desde el punto de vista del “giro icónico” en humanidades y ciencias sociales, analizo el caso concreto del auge y desaparición de la diosa Fortuna en la iconografía política...
La distribución global del ingreso. De la caída del muro de Berlín a la gran recesión
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Christoph Lakner
2015-06-01
Full Text Available Este artículo presenta una base de datos recién compilada y mejorada de encuestas nacionales de hogares entre 1988 y 2008. En 2008, el índice global de Gini es de un 70,5% después de disminuir en cerca de 2 puntos Gini en este periodo. Cuando se ajusta por el probable subregistro de los ingresos superiores de las encuestas usando la brecha entre el consumo de cuentas nacionales y el promedio de las encuestas junto con una imputación tipo Pareto de la cola superior, resulta un Gini global mucho más alto de casi un 76%. Con tal ajuste la tendencia decreciente del Gini casi desaparece. El seguimiento de la evolución de los deciles-país individuales muestra los elementos subyacentes que impulsan los cambios en la distribución global: China salió de los rangos más bajos, en el proceso se modificó la forma total de la distribución global del ingreso y se creó una importante clase “mediana” global que transformó la distribución de dos picos de 1988 en una de un pico. Los “ganadores” fueron los deciles-país que en 1988 estaba alrededor de la mediana de la distribución global, el 90% de los cuales, en términos de población, son de Asia. Los “perdedores” fueron los deciles-país que en 1988 estaban alrededor del percentil 85 de la distribución global, casi el 90% de los cuales, en términos de población, son de economías maduras.
Entre Berlín (1810) y Fráncfort (1920): de la Universidad Humboldtiana al Freie Jüdische Lehrhaus
García Farrero, Jordi; Isabel VILAFRANCA MANGUÁN; Conrad VILANOU TORRANO
2015-01-01
This article reviews the role of Jewish tradition in the Central European (Mitteleuropa) culture of the 19th and early 20th centuries. After confirming the Hebraic contribution to western culture, it examines the significance of the University of Berlin (1810) with regard to the assimilation of the Jews, an ultimately flawed project that placed a great deal of importance on the role of the German language, which became a kind of lingua franca (a new koiné) to enable free circulation and socia...
Stanienda, Katarzyna
2015-03-01
The results of investigation of the associated rocks with the Saddle Beds Coals Seams from Chwałowice Trough were presented in this article. The results of researches show that sandstones and mudstones dominate in the investigating profile. Claystones are situated mainly in ceilings and floors of coal seams. Grains of sandstones include mainly quartz, feldspars, micas and also quartzite's and gneiss's fragments. It is also possible to observe small grains of heavy minerals. Some of sandstones present bad compactness and are destroyed during transportation. This feature is connected with presence of little quantity of cement, especially in medium grained sandstones, which include more matrix than typical cement. The cement is built mainly of clay minerals, kaolinite and illite, carbonates and chalcedony but X-ray diffraction confirmed also the presence of halite in the cement of investigated sandstones. Mudstones and claystones are composed mainly of clay minerals. It's also possible to find quartz and micas there. Higher amounts of quartz and micas are possible to find rather in mudstones. The associated rocks with the Saddle Beds Coal Seams from Chwałowice Trough include also organic matter. W artykule przedstawiono wyniki badań skał towarzyszących pokładom węgla warstw siodłowych Niecki Chwałowickiej. Wyniki badań wskazują, że w badanym profilu dominują piaskowce oraz mułowce. Iłowce natomiast występują głównie w stropach i spągach pokładów węgla. Okruchy piaskowców to głównie ziarna kwarcu, skaleni, mik oraz fragmenty kwarcytów i gnejsów. Można tu również zaobserwować drobne okruchy minerałów ciężkich. Niektóre piaskowce charakteryzują się obniżoną zwięzłością i podczas transportu ulegają rozpadowi. Cecha ta związana jest z niewielką ilością spoiwa, szczególnie w piaskowcach średnioziarnistych, w których matrix przeważa nad typowym cementem. Spoiwo zbudowane jest głównie z minerałów ilastych, takich jak
Anaerobic filters for the treatment of coal gasification wastewater.
Suidan, M T; Siekerka, G L; Kao, S W; Pfeffer, J T
1983-06-01
A process train consisting of the following sequence of unit processes, a berl-saddle-packed anaerobic filter, an expanded bed, granular activated carbon anaerobic filter, and an activated sludge nitrification system was evaluated for the treatment of a synthetically prepared coal gasification wastewater. The first-stage anaerobic filter resulted in very little removal of organic matter and no methane production. Excellent reduction in organic matter occurred in the granular activated carbon anaerobic filter. The removal mechanism was initially adsorptive and near the end of the study, removal of organic matter was primarily through conversion to methane gas. It is felt that the success of the activated carbon anaerobic filter was due to the ability of the activated carbon to sequester some components of the wastewater that were toxic to the mixed culture of anaerobic microorganisms. The activated sludge nitrification system resulted in complete ammonia oxidation and was very efficient in final effluent polishing.
Energy Technology Data Exchange (ETDEWEB)
Sieres, Jaime; Fernandez-Seara, Jose [Area de Maquinas y Motores Termicos, E.T.S. de Ingenieros Industriales, University of Vigo, Campus Lagoas-Marcosende No 9, 36310 Vigo (Spain)
2007-07-15
In ammonia water absorption refrigeration systems (AARS) a high efficiency purification process to remove the water content from the generated vapour is of great importance. One type of equipment to carry out this process is a packed column. Any type of detailed analysis of a packed column requires the calculation of mass transfer coefficients. Therefore, the correlations to obtain these coefficients become an essential tool for an accurate analysis and design of these devices. An experimental facility has been designed and built to analyze the ammonia-water rectification process in packed columns. In this paper a brief description of the experimental facility is given and the variables required to analyze the column performance are explained. An analytical method to determine mass transfer coefficients from the experimental data is developed. Results of mass transfer coefficients for 15 mm glass Raschig rings, (1)/(2){sup ''} ceramic Berl saddles and (1)/(2)'' ceramic Novalox saddles random packings are reported. The experimental results are compared with different mass transfer correlations proposed in the literature. In the paper corrected correlations are proposed for the packings considered. These correlations could be used to analyze and design a packed column for AARS. (author)
2013 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Saddle Mountain
National Oceanic and Atmospheric Administration, Department of Commerce — In October 2013, WSI, a Quantum Spatial Company (QSI), was contracted by the Puget Sound LiDAR Consortium (PSLC) to collect Light Detection and Ranging (LiDAR) data...
Properties of diffusive systems near a saddle point: application to a quartic double well
Battezzati, M
2003-01-01
This paper aims at the analysis of diffusive properties of unidimensional mechanical systems in the environment of maxima and minima of the potential. It begins with a study of the properties of the singular solutions of the Hamilton-Jacobi-Yasue equation in the above-mentioned environment, in both strong or very small frictional forces. For the quartic symmetrical double-well potential, approximate solutions are found for local validity and the diffusion operator is then calculated in the limits of deep wells and small temperature, the regime being supposed to be aperiodic, with high or moderate values of frictional coefficient. This equation is proved to be nonunique. This operator is then reduced to second order by imposing suitable boundary conditions. Thus an appropriate eigenvalue equation is obtained to describe stationary states in the environment of extremal points of the potential energy function. The main interest of this work relies upon the fact that transition times between wells mainly depend u...
BASELINE PLASMA CHOLINESTERASE ACTIVITIES IN ARGENTINE SADDLE HORSES FROM SABANA DE BOGOTÁ
Directory of Open Access Journals (Sweden)
C. Ariza
2012-01-01
Full Text Available La determinación de la actividad colinesterasa (ChE en animales domésticos es de importancia en diagnóstico e investigación. El presente trabajo tuvo como objetivo principal la determinación de la línea base de actividad ChE plasmática (acetilcolines-terasa, AChE y butirilcolinesterasa, BChE en 60 caballos Silla Argentino muestreados en fincas de equinos ubicadas en Bogotá (Colombia y sus alrededores. Las actividades catalíticas de AChE y BChE plasmáticas fueron medidas mediante espectrofotome-tría visible (405 nm. Los valores promedio ± desviación estándar de actividad AChE (nmols/ml/ min para machos (n=32 fueron 1566 ± 301. En intervalos de edad, los resultados fueron, 0.5–5 años: 1526 ± 295, 6–10 años: 1532 ± 313, 11-15 años: 1615 ± 279, y > 15 años: 1617 ± 335. En hembras (n=28, la actividad AChE fue 1323 ± 432, con valores en intervalos de edad, 0.5-5 años: 719 ± 108, 6–10 años: 1603 ± 313, 11–15 años: 1225 ± 294, > 15 años: 1519 ± 369. La BChE en machos fue 3304 ± 822; con intervalos de edad, 0.5-5 años: 3383 ± 715, 6–10 años: 3360 ± 766, 11-15 años: 3267 ± 1064, > 15 años: 3206 ± 861. En hembras, la BChE fue 3097 ± 432, con intervalos de edad: 0.5-5 años: 2467 ± 981, 6–10 años: 3668 ± 750, 11-15 años: 3238 ± 979, y > 15 años: 3015 ± 925. La actividad AChE fue significativamente diferente entre machos y hembras (test t, p < 0.05 y en ambos géneros al comparar los grupos etáreos (ANAVA, p < 0.05. BChE tuvo valores más altos que AChE, sin embargo, no en forma significativa cuando se compararon los resultados entre los dos géneros, ni cuando se compararon los grupos etáreos en los dos géneros. En una prueba adicional, 15 muestras fueron tomadas al azar y mantenidas a 4oC durante 72 horas para ser anali-zadas cada 24 horas; AChE y BChE no mostraron variaciones significativas entre las mediciones hechas en este período de tiempo. El presente estudio permitió determinar lineas base de los dos tipos de colinesterasas plasmáticas en caballos tipo silla Argentino con el propósito de ofrecer valores de referencia con fines diagnósticos y comparativos para clínicos e investigadores.
Tunable strength saddle-point contacts impact on quantum rings transmission
González, J. J.; Diago-Cisneros, L.
2016-09-01
A particular subject of investigation is the role of several sadle-point contact (QPC) parameters on the scattering properties of an Aharonov-Bohm-Aharonov-Casher quantum ring (QR) under Rashba-type spin orbit interaction. We discuss the interplay of the conductance with the confinement strengths and height of the QPC, which yields new and tunable harmonic and non-harmonics patterns, while one manipulates these constriction parameters. This phenomenology may be of utility to implement a novel way to modulate spin interference effects in semiconducting QRs, providing an appealing test-platform for spintronics applications.
Generating saddle points in the merit function landscape of optical systems
Bociort, F.; Van Turnhout, M.
2005-01-01
Finding multiple local minima in the merit function landscape of optical system optimization is a difficult task, especially for complex designs that have a large number of variables. We discuss here a method that enables a rapid generation of new local minima for optical systems of arbitrary comple
Bifurcation of Degenerate Homoclinic Orbits to Saddle-Center in Reversible Systems
Institute of Scientific and Technical Information of China (English)
Xingbo LIU; Deming ZHU
2008-01-01
The authors study the bifurcation of homoclinic orbits from a degenerate homoclinic orbit in reversible system. The unperturbed system is assumed to have saddlecenter type equilibrium whose stable and unstable manifolds intersect in two-dimensional manifolds. A perturbation technique for the detection of symmetric and nonsymmetric homoclinic orbits near the primary homoclinic orbits is developed. Some known results are extended.
Graphs of NMS Flows on S3 with Knotted Saddle Orbits and No Heteroclinic Trajectories
Institute of Scientific and Technical Information of China (English)
B. CAMPOS; P. VINDEL
2007-01-01
We consider NMS systems on S3 without heteroclinic trajectories connecting two saddlesorbits and we build the dual graphs associated with this kind of flows. We prove that flows comingfrom essential attachments of orientable round 1-handles can be reproduced from the correspondingdual graph.
BIFURCATION OF LIMIT CYCLES FROM A DOUBLE HOMOCLINIC LOOP WITH A ROUGH SADDLE
Institute of Scientific and Technical Information of China (English)
HAN MAOAN; BI PING
2004-01-01
This paper concerns with the bifurcation of limit cycles from a double bomoclinic loop under multiple parameter perturbations for general planar systems. The existence conditions of 4 homoclinic bifurcation curves and small and large limit cycles are especially investigated.
Technology Improvement of the Saddle Gasket%柱塞孔精密加工技术浅析
Institute of Scientific and Technical Information of China (English)
孙永生; 张红超; 刘树彬; 李凤娟; 赵文澜
2013-01-01
通过对转子柱塞孔的结构特点和加工要素的分析，利用现有机床设备，设计专用工装夹具和刀具，合理设置工艺参数等措施，有效地保证了柱塞孔的表面质量和圆柱度。取得了较为满意的效果，并对加工要点进行了总结。%By analyzing the structural features and the machining elements of the plunger of the rotor, utilizing the machine tool equipment in hand, designing the specialized frock clamp and tool cutter, setting up the technological parameter reasonably and other measures, the surface quality and cylindricity of the plunger hole is guaranteed effectively, at the same time the fairly satisfactory result has been gained and the processing key points have been summarized.
Shameem, Nowsheen; Kamili, Azra N; Ahmad, Mushtaq; Masoodi, F A; Parray, Javid A
2016-01-01
This study pertains to the radical scavenging potential of and DNA protection by Helvella lacunosa, an edible mushroom from Kashmir Himalaya (India). Different solvents, on the basis of their polarities, were used to extract all solvent-soluble bioactive compounds. Seven different antioxidant methods were also used to determine extensive radical scavenging activity. The mushroom ethanol extract and butanol extract showed effective scavenging activity of radicals at 95% and 89%, respectively. At 800 µg/mg, the ethanol extract was potent enough to protect DNA from degradation by hydroxyl radicals. It is evident from these findings that the presence of antioxidant substances signifies the use of H. lacunosa as food in the mountainous valleys of the Himalayan region.
2010-07-21
..., mineral soil) in established campsites. In campsites where the existing amount of barren core exceeds 5... Permit Issuance in the Federal Register (FR, Vol. 70, No. 119, 36112). The purpose of this revised notice... a proposed forest plan amendment, and to revise the planned release date. FOR FURTHER...
Non-Gaussian statistics of critical sets in 2 and 3D: Peaks, voids, saddles, genus and skeleton
Gay, Christophe; Pogosyan, Dmitri
2011-01-01
The formalism to compute the geometrical and topological one-point statistics of mildly non-Gaussian 2D and 3D cosmological fields is developed. Leveraging the isotropy of the target statistics, the Gram-Charlier expansion is reformulated with rotation invariant variables. This formulation allows us to track the geometrical statistics of the cosmic field to all orders. It then allows us to connect the one point statistics of the critical sets to the growth factor through perturbation theory, which predicts the redshift evolution of higher order cumulants. In particular, the cosmic non-linear evolution of the skeleton's length, together with the statistics of extrema and Euler characteristic are investigated in turn. In 2D, the corresponding differential densities are analytic as a function of the excursion set threshold and the shape parameter. In 3D, the Euler characteristics and the field isosurface area are also analytic to all orders in the expansion. Numerical integrations are performed and simple fits a...
La responsabilidad de la economía
Keitel, Hans-Peter
2012-01-01
Conferencia pronunciada por el Presidente de la Confederación Federal de la Industria alemana (BDI) con motivo de la concesión del premio Max Weber de Ética Económica 2012, el 26 de abril 2012 en la Academia de las Ciencias de Berlín-Brandeburgo, Berlín.
Directory of Open Access Journals (Sweden)
Núñez Seixas, Xosé M.
2015-01-01
Full Text Available O artigo analisa a influência do nacional-socialismo alemão sobre o movimento fascista espanhol durante a sua primeira fase, ainda durante a guerra civil e primeira pós-guerra. Além do fascínio pela figura de Hitler, os fascistas espanhóis admiravam a modernidade da propaganda e agitação nazista. A admiração era partilhada pela direita católica. Ainda que o antissemitismo biológico constituísse um problema, todos consideravam Hitler como a defesa mais eficaz perante a expansão bolchevique
Stability of Homoclinic Cycles to a Saddle-focus in Space System%空间系统鞍焦点同宿环的稳定性
Institute of Scientific and Technical Information of China (English)
黄璇; 王丽英
2009-01-01
文章在可定义回复映射的条件下,按照Wiggins在文献[2]中介绍的构造Poincar(e)映射的方法,给出了空间系统鞍焦点同宿环在其部分邻域中是渐近稳定或不稳定的判据.
Directory of Open Access Journals (Sweden)
Francesca Martuzzi
2010-01-01
Full Text Available Aim of this work was to investigate nursing mares milk characteristics at the end of lactation (D and to make a comparisonwith milk taken during early lactation (3 to 30 d post partum (E. The survey was carried out on 17 Italian Saddlemares (IS (193 days in milk; 147 pregnancy days and on 12 Haflinger mares (H (174 days in milk; 146 pregnancydays. N fractions were determined by means of Kjeldahl; fat and lactose by means of mid infrared lectures; mineral elementswere determined by Atomic Absorption Spectrophotometry; P by colorimetry. Data referring to 58 individual milksamples were analyzed by ANCOVA. Significant variations, similar in both breeds, were observed (E vs D for density at15°C (1.036 vs 1.034, pH (6.94 vs 7.24, titratable acidity (3.56 vs 1.70 °SH, fat (1.17 vs 0.76% g/100g of milk,crude protein (2.31 vs 1.68% g/100g, casein number (52.37 vs 46.59 and ash (0.50 vs 0.30% g/100g; similarly(mg/100g for non casein N (172.31 vs 142.05, non protein N (34.43 vs 29.09, P (61.30 vs 32.48, Ca (112.88 vs54.42, Mg (8.40 vs 4.38 and K (60.77 vs 41.31. Freezing point, lactose and Na showed no significant variations. Atthe end of lactation, milk resulted poorer in all main organic components, except lactose, and in all mineral components,except Na. Only freezing point and phosphorus variations differed in IS from H. Breed significantly affected fat, casein Nand ash mean contents.
The saddle-shaped historical trail of the evolution of Chinese sexology%中国性学发展的马鞍形史迹
Institute of Scientific and Technical Information of China (English)
王明辉
1996-01-01
@@ 中医性学源远流长,根据有关史料,论述其发展史迹有如一双峰的马鞍形-始源于远古商周,筑基于春秋先秦,鼎盛于秦汉隋唐,阻滞于宋元两朝,徘徊于明清近代,发扬于新建中国.
President Ilves ja Simon Peres avasid Tallinna uue sünagoogi / Evely Baum, Riina Leminsky
Baum, Evely
2007-01-01
16. mail 2007 avati pidulikult Tallinna uus juudi sünagoog. Avamistseremoonial osalesid ka Eesti president Toomas Hendrik Ilves ja peaminister Andrus Ansip, Iisraeli asepeaminister Simon Peres, Iisraeli pearabi Yona Metzger, Venemaa pearabi Berl Lazar
Judaica et Aegyptiaca : de Maccabaeorum libro III quaestiones historicae
Cohen, Jakob
1941-01-01
Disputans de libro, quem composuerat H. Willrich, inscripto "Judaica, Forschungen zur hellenistisch-jiidischen Geschichte und Litteratur", 1900, dixit P. Wendland (Berl. Philol. Wochenschrift anni 1900, p. 1197 seqq.) : "Ich unterschreibe Willrichs Urteil, dasz die Geschichte des hellenistischen Jud
Lifescience Database Archive (English)
Full Text Available larval stages of pentastomes (tongue worms). Its definitive hosts are reptiles whilst humans serve as rare ...v_factor) Pantchev N, Tappe D Pentastomiasis and other parasitic zoonoses from reptiles and amphibians. Berl
Melanocortin and Opioid Peptide Interactions in the Modulation of Binge Alcohol Drinking
2013-04-01
antagonist, modulates the behavioral effects of morphine in mice. Psychopharmacology (Berl) 180(2):279-85. Fan AZ, Russell M, Stranges S, Dorn J...amygdala, hippocampus , and hypothala- mus (Bloch et al., 1979; Dube et al., 1978; Jacobowitz and O’Donohue, 1978; O’Donohue and Jacobowitz, 1980; O’Donohue...behavioral effects of morphine in mice. Psychopharmacology (Berl) 180:279–285. Fetissov SO, Bergstrom U, Johansen JE, Hokfelt T, Schalling M, Ranscht B
Directory of Open Access Journals (Sweden)
Jean Pierre Matus A.
2005-01-01
Full Text Available En este artículo se reseña el texto del Prof. Dr. Kai Ambos, Der Allgemeine Teil des Völkerstrafrechts y, al mismo tiempo, se propone la aplicación de los principales resultados de esa obra para un eventual enjuiciamiento de la tortura masiva y sistemática aplicada en Chile entre 1973 y 1990, tal y como se describe en el Informe de la Comisión Nacional de Prisión Política y Tortura (Informe Valech. Así, se comienza describiendo y analizando la sistematización propuesta por Ambos para una parte general del derecho penal internacional, luego se analiza la tortura como crimen contra la humanidad, sujeto a las reglas del derecho penal internacional. En este apartado se determinan sus elementos principales (el carácter masivo y sistemático, el Tribunal competente en Chile para conocer de estas causas y el procedimiento aplicable. A continuación se describen los hechos, tal y como se dieron a conocer en el Informe Valech, que permiten concluir que en Chile se aplicó la tortura de manera masiva y sistemática durante el régimen militar, favorecida por éste, mediante el establecimiento de una "maquinaria" de represión "legalizada". Enseguida, se determina la existencia de una responsabilidad penal internacional individual derivada de estos hechos, para, a continuación, pasar a analizar los principales problemas de la parte general del derecho penal internacional que se presentarían en el caso de juzgarse tales responsabilidades individuales, siguiendo el esquema de análisis en dos niveles propuesto por Kai Ambos, a saber, discutiendo primero los presupuestos objetivos y subjetivos de esa responsabilidad, para finalizar analizando las principales defensas que podrían oponerse por los eventuales acusados.This article reviews Prof. Dr. Kai Ambos' book, Der Allgemeine Teil des Völkerstrafrechts, and proposes the application of the main results of this book to the possible trial of the acts of massive and systematic torture carried out in Chile between 1973 and 1990, described in the report of the National Commission on Political Imprisonment and Torture (also known as the Valech Report. We therefore begin by describing and analyzing Prof. Ambos' system for a general part of international penal law, and then torture is analyze as a crime against humanity, subject to the rules of international penal law. Here we determine its main elements (a massive and systematic character, the competent tribunal in Chile for this matters, and the procedure to be applied. We next turn to the description of the facts, as rendered in the Valech Report, which brings us to the conclusion that torture was applied in Chile in a massive and systematic way during the military regime, which supported it through the establishment of a "legalized" repression "machinery". Next, the existence of an individual penal responsibility derived from these facts is determined, followed by the analysis of the main problems of the general part of international penal law which would emerge if those responsible individuals were brought to trial. In this we follow the two-level scheme of analysis proposed by Kai Ambos, namely, discussing first the objective and subjective presuppositions for this responsibility, and then turning to the analysis of the main defenses available to the defendants.
Institute of Scientific and Technical Information of China (English)
袁春红
2014-01-01
首先在序拓扑线性空间中定义了集值映射多目标半定规划问题的Kuhn-Tucker鞍点,在广义锥-次类凸条件下,讨论了此集值优化问题的弱有效解和Ben-Son真有效性解与Kuhn-Tucker鞍点之间的关系.
Institute of Scientific and Technical Information of China (English)
王其林
2007-01-01
首先在局部凸Hausdorff拓扑向量空间中定义了集值优化问题的Kuhn-Tucker鞍点,在近似锥一次类凸集值映射下,讨论了集值优化问题的强有效解与Kuhn-Tucker鞍点之间的关系.
Institute of Scientific and Technical Information of China (English)
王长宇; 孙丰荣; 梅良模; 宋尚玲
2006-01-01
利用Eikonal方程的粘性解给出了基于单幅图像的凸面三维重建算法;定义了2类鞍面--加性鞍面和乘性鞍面.利用凸面法和凹面法从鞍面单幅图像重建2个抛物柱面,然后根据鞍面的结构特点将2个抛物柱面重新合成鞍面.文中算法从临界点开始计算,不要求边界条件,具有较高的精确度.最后通过实验分析了该算法对噪声的敏感性.
Institute of Scientific and Technical Information of China (English)
余国林
2012-01-01
讨论集值向量优化的标量化和鞍点问题.在生成锥内部凸-锥-类凸假设下,建立了集值向量优化问题在(弱)有效和Benson真有效意义下的标量化定理和鞍点定理.
The new synagogue has given the Jewish community something to sing and dance about / Rein Sikk
Sikk, Rein, 1961-
2007-01-01
Tallinnas Karu tänaval avati 16. mail 2007 uus juudi sünagoog, avamistseremoonial viibisid Iisraeli asepeaminister Shimon Peres, Eesti president Toomas Hendrik Ilves, peaminister Andrus Ansip, Venemaa pearabi Berl Lazar, Iisraeli pearabi Yona Metzger ja sünagoogi suurrahastaja Aleksander Bronštein. President Toomas Hendrik Ilves viitas oma kõnes paralleelidele eestlaste ja juutide ajaloos
Clinard, Linda M.; Miron, Louis; Ariav, Tamar; Botzer, Iris; Conroy, Judy; Laycock, Kathy; Yule, Kathy
The University of California Irvine (UCI) and Beit Berl College (BBC) in Israel developed an action research project with cooperating teachers at their Professional Development Schools. This paper examines perceptions of UCI and BBC cooperating teachers within each culture and across cultures regarding: (1) contributions teachers provide to…
Ferrell, A.; Liang, Hao; Renneboog, Luc
2016-01-01
In the corporate finance tradition, starting with Berle and Means (1932), corporations should generally be run to maximize shareholder value. The agency view of corporate social responsibility (CSR) considers CSR an agency problem and a waste of corporate resources. Given our identification strategy
В Таллинне открылась новая синагога / Ксения Репсон
Репсон, Ксения
2007-01-01
Tallinnas Karu tänaval avati 16. mail 2007 uus juudi sünagoog, avamistseremoonial viibisid Iisraeli asepeaminister Shimon Peres, Eesti president Toomas Hendrik Ilves, peaminister Andrus Ansip, Venemaa pearabi Berl Lazar, Iisraeli pearabi Yona Metzger ja sünagoogi suurrahastaja Aleksander Bronštein. President Toomas Hendrik Ilves viitas oma kõnes paralleelidele eestlaste ja juutide ajaloos
2012-05-01
Berl). 2002;164:250–261. 7. Lieberman HR, Falco CM, Slade SS. Carbohydrate administration during a day of sustained aerobic activity improves...and risk behaviors associated with combined alcohol and energy drink consumption in college drinkers. Addict Behav. 2011;36:1133–1140. 38. Marczinski CA
Directory of Open Access Journals (Sweden)
Alejandro Curiel Ramírez del Prado
2016-06-01
Full Text Available Andreas Brockmann, Ämtersysteme. Dynamik und Funktionen von Ämtersystemen im Einflussgebiet des ehemaligen spanischen Kolonialreiches in Amerika. Berlín: Lit Verlag, 2014 (Ethnologische Studien Bd. 45, IX+367 pp., ISBN 978-3-643-12502-6.
Kas Venemaa ülemrabil on õigus?
2004-01-01
Ilmunud ka: Severnoje Poberezhje, 20. juuli 2004, lk. 2. Venemaa ülemrabi Berl Lazar pöördus Euroopa Komisjoni presidendi Romano Prodi poole üleskutsega anda hinnang Eesti võimude tegevusele, mis rabi meelest soosib kohalikke natse. Küsimusele vastab Ida-Viru juudi kogukonna juht Aleksandr Dusman
Vene pearabi süüdistab Eestit natsismilembuses / Sigrid Laev
Laev, Sigrid
2004-01-01
Venemaa ülemrabi Berl Lazar'i protestist Saksa sõjaväes teeninud Eesti sõduritele Tallinnasse memoriaali rajamise vastu. Eesti välisminister Kristiina Ojulandi hinnangul on tegu välisriigi siseasjadesse sekkumisega. Kommenteerib Eesti pearabi Shmuel Kot
Downy mildew (DM), caused by Plasmopara halstedii (Farl.) Berl. et de Toni, is one of the serious sunflower diseases in the world due to its high virulence and the variability of the pathogen. DM resistance in the USDA inbred line, HA 458, has been shown to be effective against all virulent races of...
Holography on Non-Orientable Surfaces
Maloney, Alexander
2016-01-01
We consider the holographic computation of two dimensional conformal field theory partition functions on non-orientable surfaces. We classify the three dimensional geometries that give bulk saddle point contributions to the partition function, and find that there are fewer saddles than in the orientable case. For example, for the Klein bottle there is a single smooth saddle and a single additional saddle with an orbifold singularity. We argue that one must generally include singular bulk saddle points in order to reproduce the CFT results. We also discuss loop corrections to these partition functions for the Klein bottle.
Holography on non-orientable surfaces
Maloney, Alexander; Ross, Simon F.
2016-09-01
We consider the holographic computation of two-dimensional conformal field theory partition functions on non-orientable surfaces. We classify the three dimensional geometries that give bulk saddle point contributions to the partition function, and find that there are fewer saddles than in the orientable case. For example, for the Klein bottle there is a single smooth saddle and a single additional saddle with an orbifold singularity. We argue that one must generally include singular bulk saddle points in order to reproduce the CFT results. We also discuss loop corrections to these partition functions for the Klein bottle.
Cyclicity of a kind of degenerate polycycles through three singular points
Institute of Scientific and Technical Information of China (English)
ZHAO Liqin
2005-01-01
This paper deals with the cyclicity of a kind of degenerate planar polycycles through a saddle-node P0 and two hyperbolic saddles P1 and P2, where the hyperbolicity ratio of the saddle P1 (which connects the saddle-node with hh-connection) is equal to 1 and that of the other saddle P2 is irrational. It is assumed that the connections between P0 to P2 and P0 to P1 keep unbroken. Then the cyclicity of this kind of polycycle is no more than m + 3 if the saddle P1 is of order m and the hyperbolicity ratio of P2 is bigger than m.Furthermore, the cyclicity of this polycycle is no more than 7 if the saddle P1 is of order 2 and the hyperbolicity ratio of P2 is located in the interval (1, 2).
Institute of Scientific and Technical Information of China (English)
刘文领; 邓学军; 马金换; 罗永兴; 胡思光; 黄芳
2005-01-01
为观察腰-硬联合穿刺针用于鞍麻防止术后头痛发生的效果,将100例鞍麻患者随机分A,B两组各50例.A组:选用腰-硬联合穿刺针"亚光牌"16号硬膜外穿刺针,配套5号长腰穿针.B组:用"亚光牌"7号普通腰穿针.局麻药用0.75%布比卡因1.2ml加50%葡萄糖液0.1ml.随访观察麻醉后5d头痛发生率.结果显示,A组无1例头痛发生.B组17例出现头痛,伴呕吐2例,其中12例经对症治疗后症状消失,5例症状严重,加用硬膜外腔注射生理盐水填充治疗加口服去痛片后恢复.结果表明,腰-硬联合穿刺针用于鞍麻穿刺可明显减少脑脊液外漏引起的低压性头痛和假性脑脊膜炎引起的高压性头痛.
Institute of Scientific and Technical Information of China (English)
王卫玲; 张黎旭; 吴军; 殷咸青; 王安; 杨健楠
2016-01-01
含大尺寸马鞍形焊缝薄壁壳体的焊接变形规律复杂、焊后矫形难度大.本文采用试验测试和数值模拟相结合的方法定量评估了用激光焊取代传统TIG电弧焊后含大尺寸马鞍形焊缝D406A超高强钢固体发动机壳体(MKT)焊接残余变形的控制效果.论文建立了D406A超高强钢焊接过程的三维热弹塑有限元模型;开展了含大尺寸马鞍形焊缝D406A超高强钢简体试验件(MTT)的TIG焊试验;采用三维全场静态变形测量系统(XJDP)测量MTT焊后残余变形,并用于D406A超高强钢焊接三维热弹塑有限元模型的修正和验证;采用验证后的有限元模型计算获得了MKT的TIG焊接残余变形和激光焊接残余变形.结果表明:两种方法焊接MKT后引起的残余变形趋势相同;激光焊接后MKT的残余变形最大值为1.68mm,远远小于手工TIG焊的最大焊接残余变形7.23mm.研究结果将为含复杂形状长焊缝超高强钢固体发动机壳体焊接工艺的更新换代提供数据支持.
Directory of Open Access Journals (Sweden)
NÉMETH, Krisztina
2013-09-01
Full Text Available This paper is an attempt to reconstruct the past and present life of the inhabitants of a former manorial village through the deep analysis of a narrative biographical interview. The hermeneutic case reconstruction focuses mainly on a person’s biography, seeking to grasp lived experience and its narrative account both separately and in their dynamic interrelation. Although every biographical narrative is unique, the present analysis tries to extract the elements of social history from the individual life story and in this way to reconstruct the mentality, common knowledge and norms, or generally speaking, the life of the manorial servants in the studied Transdanubian manorial village before World War II. In order to improve our knowledge of the manorial servants, which has so far relied on sociographies, or ‘snapshots’, of their lives produced by various authors from the 1930s to the 1980s, the time frame of the analysis has been extended to the post-socialist period following the democratic transition as well. In addition, the study pays a particular attention to the presence of cultural continuities, discontinuities, and eventual traumatic breaks in the life stories. Certain historical turning points are also highlighted as potentially traumatizing events, in connection of which the analysis seeks answers to the following questions: How did the former manorial servants experience these events? What was their typical, individual and collective response? What kinds of survival strategies did they choose to endure radical changes that tended to reshape the life style, rewrite the norms and values, and affect the whole world of their community? What traces did these events leave on their individual and collective identities?
Personalized Medicine in Veterans with Traumatic Brain Injuries
2014-07-01
pathogenesis of neurological disorders such as Alzheimer’s disease and may be used to monitor disease diagnosis and progression [18,19]. Thus, PBMCs...alternative splicing of the serotonin 2c receptor [38], and that patients with autism and Prader-Willi-like characteristics are found to have reduced...and skeletal muscle disease: implications for pathogenesis and therapy. J Mol Med (Berl) 2011; 89: 1065-1077. [24] Pasinetti GM, Fivecoat H, and Ho
2005-12-01
Philippens, unpublished results 2000). During the first three weeks stress alone had a positive effect on the activity and exploration. During the...390-400, 1983. Kleinwaechter, L. Beobachtung uber die Wirkung des Calabar-Extracts gegen Atropin- Vergiftung. Berl. Klin. Wschr. 1 369-371, 1864... Marketing en Communicatie, digitale versie via Archief 21 ex. TNO Defensie en Veiligheid, vestiging Rijswijk, afdeling Tekstverwerking (digitale versie)
Lara, Luis Fernando
2013-01-01
Esta nueva publicación del Instituto lberoamericano de Berlín se originó en el "Taller sobre el español de América" que tuvo lugar en la Universidad de Leipzig en octubre de 1991. Sin embargo, no contiene todas las ponencias que se presentaron en el y, en cambia, agrega otras, así como precisiones, sugerencias y comentarios que enriquecen la publicación.
Finite Larmor radius influence on MHD solitary waves
Directory of Open Access Journals (Sweden)
E. Mjølhus
2009-04-01
Full Text Available MHD solitons are studied in a model where the usual Hall-MHD model is extended to include the finite Larmor radius (FLR corrections to the pressure tensor. The resulting 4-dimensional set of differential equations is treated numerically. In this extended model, the point at infinity can be of several types. Necessary for the existence of localized solutions is that it is either a saddle-saddle, a saddle-center, or, possibly, a focus-focus. In cases of saddle-center, numerical solutions for localized travelling structures have been obtained, and compared with corresponding results from the Hall-MHD model.
2010-07-01
..., pipeline, electronic transmission line, fence, water transmission facility, or fiber optic cable. Major... for pecuniary remuneration or other gain any saddle or pack animal, vehicle, boat, camping gear,...
Holographic partition functions and phases for higher genus Riemann surfaces
Maxfield, Henry; Ross, Simon F.; Way, Benson
2016-06-01
We describe a numerical method to compute the action of Euclidean saddle points for the partition function of a two-dimensional holographic CFT on a Riemann surface of arbitrary genus, with constant curvature metric. We explicitly evaluate the action for the saddles for genus two and map out the phase structure of dominant bulk saddles in a two-dimensional subspace of the moduli space. We discuss spontaneous breaking of discrete symmetries, and show that the handlebody bulk saddles always dominate over certain non-handlebody solutions.
Local and Global Bifurcations With Nonhyperbolic Equilibria
Institute of Scientific and Technical Information of China (English)
孙建华; 罗定军
1994-01-01
The normal forms of coupling functions governing local and global bifurcations are studied for a generic (d+1) -parameter family of three-dimensional systems with a heteroclinic orbit connecting a hyperbolic saddle and a nonhyperbolic equilibrium occurring in the saddle-node,transcritical and pitchfork bifurcations,respectively.Singularity theory and a version of Melnikov function are used in this paper.
Average Transient Lifetime and Lyapunov Dimension for Transient Chaos in a High-Dimensional System
Institute of Scientific and Technical Information of China (English)
陈洪; 汤建新; 唐少炎; 向红; 陈新
2001-01-01
The average transient lifetime of a chaotic transient versus the Lyapunov dimension of a chaotic saddle is studied for high-dimensional nonlinear dynamical systems. Typically the average lifetime depends upon not only the system parameter but also the Lyapunov dimension of the chaotic saddle. The numerical example uses the delayed feedback differential equation.
Rigidity result on conjugacies of families of diffeomorphisms
Institute of Scientific and Technical Information of China (English)
李伟固; 章梅荣
1997-01-01
Embedding flows are used to obtain a rigidity result on strongly topological conjugacy of families of diffeomorphisms,i.e.families of C4(2≤r≤∞) diffeomorphisms,the strongly topologically conjugating homeomor-phisms near degenerate saddle-nodes will be differentiable on center manifolds of the saddle-nodes.
Kips, A.; Vassen, W.; Hogervorst, W.; Dando, P.A.
1998-01-01
We present scaled-energy spectra on helium Rydberg atoms in a static electric field. /M/ = 1 states were studied in excitation from the 2 S-1(0) metastable state. Spectra were recorded for epsilon = -2.940(4), epsilon = -2.350(4), both below the saddle point, and epsilon = -1.760(4), above the saddl
Valley Singularities and Baryon Number Violation
Provero, P
1994-01-01
We consider the valley--method computation of the inclusive cross section of baryon number violating processes in the Standard Model. We show that any physically correct model of the valley action should present a singularity in the saddle point valley parameters as functions of the energy of the process. This singularity prevents the saddle point configuration from collapsing into the perturbative vacuum.
Local and global bifurcations at infinity in models of glycolytic oscillations
DEFF Research Database (Denmark)
Sturis, Jeppe; Brøns, Morten
1997-01-01
We investigate two models of glycolytic oscillations. Each model consists of two coupled nonlinear ordinary differential equations. Both models are found to have a saddle point at infinity and to exhibit a saddle-node bifurcation at infinity, giving rise to a second saddle and a stable node...... at infinity. Depending on model parameters, a stable limit cycle may blow up to infinite period and amplitude and disappear in the bifurcation, and after the bifurcation, the stable node at infinity then attracts all trajectories. Alternatively, the stable node at infinity may coexist with either a stable...... sink (not at infinity) or a stable limit cycle. This limit cycle may then disappear in a heteroclinic bifurcation at infinity in which the unstable manifold from one saddle at infinity joins the stable manifold of the other saddle at infinity. These results explain prior reports for one of the models...
Institute of Scientific and Technical Information of China (English)
宋乐; 韩荣飞; 许学; 刘斌美; 徐宏青; 张瑛; 吴跃进
2011-01-01
为探讨马鞍型剂量效应曲线的形成机制,研究了盐胁迫、真空胁迫处理对低剂量辐照诱导效应的影响.利用不同剂量的Υ射线(60、90、120、150、210、282、423和560Gy)辐照水稻种子后,以苗高为辐射损伤的生物学终点,调查γ射线辐照种子经真空处理和不同浓度的NaC1胁迫处理的损伤情况,利用Origin 8.0软件对剂量-苗高数据进行线性拟合；结果表明:低剂量辐照既能诱导对真空胁迫、盐胁迫的适应性反应,同时又和真空胁迫、盐胁迫具有协同抑制水稻苗高的作用,获得的剂量-苗高曲线为马鞍型的形状.低剂量辐照加上环境因子胁迫,对水稻种子产生的适应性反应可能是马鞍型剂量-效应曲线的形成机制.
MONDian three-body predictions for LISA Pathfinder
Energy Technology Data Exchange (ETDEWEB)
Bevis, Neil; Magueijo, Joao [Theoretical Physics, Blackett Laboratory, Imperial College, London, SW7 2BZ (United Kingdom); Trenkel, Christian; Kemble, Steve, E-mail: n.bevis@imperial.ac.u, E-mail: magueijo@ic.ac.u, E-mail: Christian.Trenkel@astrium.eads.ne [Astrium Ltd, Gunnels Wood Road, Stevenage SG1 2AS (United Kingdom)
2010-11-07
In previous work it was shown that modified Newtonian dynamics (MOND) theories predict anomalously strong tidal stresses near the saddle points of the Newtonian gravitational potential. An analytical examination of the saddle between two bodies revealed a linear and a nonlinear solution, valid for the outer and inner regions. Here we present a numerical algorithm for solving the MOND equations. We check the code against the two-body analytical solutions and explore the region transitioning between them. We then develop a realistic model for the MONDian effects on the saddles of the Sun-Earth-Moon system (including further sources is straightforward). For the Sun-Earth saddle we find that the two-body results are almost unchanged, with corrections increasing from full to new Moon. In contrast, the Moon saddle is an intrinsically three-body problem, but we numerically find a recipe for adapting the two-body solution to this case, by means of a suitable rescaling and axis reorientation. We explore possible experimental scenarios for LISA Pathfinder and the prospect of a visit to the saddle(s) at the end of the mission. Given the chaotic nature of the orbits, awareness of the full range of the possibilities is crucial for a realistic prediction. We conclude that even with very conservative assumptions on the impact parameter, the accelerometers are abundantly sensitive to vindicate or rule out the theory.
Study of the Wada fractal boundary and indeterminate crisis
Institute of Scientific and Technical Information of China (English)
洪灵; 徐健学
2002-01-01
By using the generalized cell mapping digraph (GCMD) method, we study bifurcations governing the escape ofperiodically forced oscillators in a potential well, in which a chaotic saddle plays an extremely important role. In thispaper, we find the chaotic saddle, and we demonstrate that the chaotic saddle is embedded in a strange fractal boundarywhich has the Wada property, that any point on the boundary of that basin is also simultaneously on the boundary ofat least two other basins. The chaotic saddle in the Wada fractal boundary, by colliding with a chaotic attractor, leadsto a chaotic boundary/crisis with a global indeterminate outcome which presents an extreme form of indeterminacy ina dynamical system ./We also investigate the origin and evolution of the chaotic saddle in the Wada fractal boundary,particularly concentrating on its discontinuous bifurcations (metamorphoses). We demonstrate that the chaotic saddlein the Wada fractal boundary is created by the collision between two chaotic saddles in different fractal boundaries.After a final escape bifurcation, there only exists the attractor at infinity; a chaotic saddle with a beautiful pattern isleft behind in phase space.
Holographic partition functions and phases for higher genus Riemann surfaces
Maxfield, Henry; Way, Benson
2016-01-01
We describe a numerical method to compute the action of Euclidean saddlepoints for the partition function of a two-dimensional holographic CFT on a Riemann surface of arbitrary genus, with constant curvature metric. We explicitly evaluate the action for the saddles for genus two and map out the phase structure of dominant bulk saddles in a two-dimensional subspace of the moduli space. We discuss spontaneous breaking of discrete symmetries, and show that the handlebody bulk saddles always dominate over certain non-handlebody solutions.
Solid T-spline Construction from Boundary Triangulations with Arbitrary Genus Topology
2012-04-01
its polycube only con- tains one single cube. For the kitten model, there are three sad- dle points (one merging saddle point and two splitting saddle...s) Isis 0 (5,863, 11,722) 9,310 (8, 8) 244 5,335 (0.12, 1.0) 52.0 Kitten 1 (5,377, 10,754) 4,825 (12, 12) 140 2,883 (0.08, 1.0) 14.8 Eight 2 (766...Fig. 13. Kitten model with genus one. (a) The input boundary triangle mesh; (b) the harmonic scalar field; (c) the constructed polycube and the
Insight into Phenomena of Symmetry Breaking Bifurcation
Institute of Scientific and Technical Information of China (English)
FANG Tong; ZHANG Ying
2008-01-01
@@ We show that symmetry-breaking (SB) bifurcation is just a transition of different forms of symmetry, while still preserving system's symmetry. SB bifurcation always associates with a periodic saddle-node bifurcation, identifiable by a zero maximum of the top Lyapunov exponent of the system. In addition, we show a significant phase portrait of a newly born periodic saddle and its stable and unstable invariant manifolds, together with their neighbouring flow pattern of Poincaré mapping points just after the periodic saddle-node bifurcation, thus gaining an insight into the mechanism of SB bifurcation.
Stress Potentiates Early and Attenuates Late Stages of Visual Processing
2011-01-19
A.J.S.). We thank K. Berling, S. Blume, D. Cole, I. Dolski, L. Friedman, J. Koger, J. Nichols, and A. Teche for assistance; and A. Fox, A. Heller , J...monkey. J Neurosci 9:81–93. Qin S, Hermans EJ, van Marle HJ, Luo J, Fernández G (2009) Acute psycho- logical stress reduces working memory-related...Neurosci 11:843– 850. van Marle HJ, Hermans EJ, Qin S, Fernández G (2009) From specificity to sensitivity: how acute stress affects amygdala processing of
Competitividad y ordenamiento económico en una economía de mercado
Weidmann, James
2013-01-01
Traducción al Castellano: Realizada por el Prof. Dr. Eugenio Recio Figueras del original alemán “Wettbewerbsfähigkeit und marktwirtschaftliche Ordnung”, Conferencia pronunciada en el Encuentro del Año Nuevo del Verband der Automovil industrie, en Berlín el 30 de enero 2013. La segunda parte corresponde a una parte de la Conferencia pronunciada el 11 de febrero de 2013 en el Walther Eucken Institut de Freiburgo con el título “Krisenmanagement und Ordnungspolitik”, publicada en Auszüge Press...
El desmantelamiento de la utopía moderna. ¿Hacia una nueva cultura política?
Flamarique, L. (Lourdes)
2011-01-01
La tesis que se va a desarrollar en las páginas que siguen es que los acontecimientos políticos vividos en Europa hace casi un cuarto de siglo no pueden ser vistos como una revitalización del proyecto político moderno: la pérdida de peso y significado de las ideas y convicciones que lo sustentaban ha seguido imparable y con ella el deterioro de la cultura política tradicional. La caída del muro de Berlín, por su significado y visibilidad, permite fijar con precisión temporal el comienzo...
G. Hoppe
2000-01-01
Der Berufung von C. S. Weiss an die Universität Berlin im Jahre 1810 gingen Entwicklungen voraus, die durch die Kristallographie des Franzosen R. J. Haüy, besonders durch dessen Lehrbuch der Mineralogie, ausgelöst wurden. Sie stehen mit der Übersetzung dieses Lehrbuchs im Zusammenhang und führten zur Qualifizierung von C. S. Weiss zum Mineralogen und Kristallographen sowie zur weiteren Entwicklung der Kristallographie innerhalb des Lehrgebäudes der Mineralogie. Den Anstoß gab der mit dem Berl...
Transgenic resistance of eggplants to the Colorado potato beetle
1999-01-01
The subject of this thesis is the use of transgenic plant resistance as a method to control the Colorado potato beetle, Leptinotarsa decemlineata Say in eggplant. The gene conferring resistance is coding for a Cry3B toxin and it is a synthetic version of a wild-type gene originally obtained from the soil bacterium Bacillus thuringiensis Berl.Eggplant cultivations are constantly attacked by a number of serious pests (e.g. the fruit and shoot borer, the Colorado potato beetle, soil-borne fungi)...
Cabañas Bravo, Miguel
2010-01-01
Se analiza la gestión de la política artística y la labor de salvaguarda del patrimonio artístico-cultural que llevaron a cabo, al frente de la Dirección General de Bellas Artes, tanto el historiador del arte Ricardo de Orueta (Málaga, 1868-Madrid, 1939), como el joven cartelista y publicista Josep Renau (Valencia 1907-Berlín 1982). El primero accedió al cargo en dos trascendentes períodos de la II República (de abril de 1931 a diciembre de 1933 y de febrero a septiembre de 1936), imponi...
Ribes Llopes, Inmaculada
2012-01-01
Políticas de las colecciones de RiuNet, repositorio institucional de la Universitat Politècnica de València cuyo objetivo es ofrecer acceso en Internet a la producción científica, académica y corporativa de la comunidad universitaria con la finalidad de aumentar su visibilidad y hacerla accesible y preservable. Riunet responde al compromiso de la Universidad en el marco de la Iniciativa por el Accesso Abierto de Budapest, con su adhesión a la Declaración de Berlín y su Política institucional ...
Cortometraje "El hombre de la arena".
CECA BASTANTE, FEDERICO
2015-01-01
[IN] This work is about making a short fiction film based on the story “Der Sandmann” the German writer E.T.A. Hoffmann (Hoffmann E.T.A. Die Nachtsücke. Berlín 1917). In this paper we will proceed to identify and explain all the parts that have been necessary for the implementation of the project by making girst a brief description of both the figure of Hoffmann as his story “Der Sandmann” ending with a short summary of the study the sinister Sigmund Freud, who used this ...
El africanismo español y la labor comunicadora del Instituto de Estudios Africanos
Lic. Victoriano Darias de las Heras
2002-01-01
Cuando a mediados de S. XIX, y siguiendo las huellas de una escogida serie de arriesgados exploradores, Europa inicia la “carrera de África”, culminada en su primera fase con el reparto del continente en la histórica Conferencia de Berlín de 1885, un variado aunque no muy numeroso grupo de entusiastas “africanistas” españoles consideraron que, por razones históricas y geopolíticas, España debería estar presente.
Tres placas de yeserías mudéjares en museos europeos
Directory of Open Access Journals (Sweden)
Jordano Barbudo, M.ª Ángeles
2012-12-01
Full Text Available These unpublished plaques with a Toledan provenance are in the Victoria & Albert Museum and the Museum of Islamic Art of Berlin. Two of the plaques are unique in that they combine mocarabe honeycomb arches with ataurique and a series of human heads in relief.
Estas placas inéditas procedentes de Toledo se encuentran en el Victoria & Albert Museum y el Museum für Islamische Kunst de Berlín. Dos de las planchas presentan la singularidad de combinar mocárabes con ataurique y una serie de cabezas humanas en relieve.
El expresionismo cinematográfico: nostalgia del romanticismo
Sánchez-Biosca, Vicente
1998-01-01
El 27 de febrero de 1920 se estrenaba en el prestigioso Marmorhaus de Berlín El gabinete del Dr. Caligari. Película insoslayable en la historia de la vanguardia cinematográfica, su sorprendente utilización de decorados influidos por el estilo Der Sturm, la crispada y convulsiva interpretación de algunos de sus actores en el estilo del teatro expresionista y una narración relativamente enrevesada y llena de dobletes, sellarían el nacimiento de un mito. La película de Wiene fue el primer filme ...
El programa ético de la economía de mercado
Homann, Karl
2007-01-01
"La Economía de Mercado es considerada insolidaria, porque premia el egoísmo y el materialismo. Estas reservas de tipo moral tienen consecuencias políticas: bloquean las reformas necesarias" lo analizó el Prof.Dr.Dr. Karl Homann, Profesor de Filosofía y Economía de la Ludwig-Maximilians-Universidad de Munich, con motivo de la concesión del premio Max-Weber 2006, el 13 de noviembre del 2006 en la academia berlinesa-brandeburguesa de las Ciencias de Berlín. Estas objeciones morales de los ciuda...
La espacialidad radical: transmutando espacios de acción y reacción
2015-01-01
RESUMEN. Tres casos de estudio: “Take the square” en la Plaza de Tahrir, El Cairo, “Occupy Wall Street” en la Plaza de Zuccotti Park en New York, y Kreuzberg, barrio subversivo de Berlín; dos acontecimientos situados, una situación que se ha ido consolidando. Éstos son los elementos que conforman una investigación que pretende llegar a definir la espacialidad radical a través de la espontaneidad y de una necesidad de ocupar un lugar por parte de las multitudes y cuerpos creados pr...
Una sociedad anestesiada: la educación como alternativa para salir de la anestesia
Rodríguez-Sedano, A. (Alfredo)
2002-01-01
Se aborda un problema latente en la sociedad y que es fuente de continuos equívocos: una sociedad bajo los efectos de la anestesia provocada por la colonización económica de la esfera pública. Las reacciones políticas y sociales, en la declaración de Berlín (2000), buscan una salida a una concepción social regida bajo criterios ligados al proceso que se deriva de las leyes de mercado. La noción de ámbito, que se propone, es de gran utilidad a la hora de acoger el desafío ...
Después de la bancarrota. Sobre la necesidad de un orden internacional. Jürgen Habermas (entrevista)
García, Fernando
2012-01-01
Se trata de una entrevista que el diario alemán Die Zeit realizó al filósofo Jürgen Habermas, el 6 de noviembre de 2008. En la entrevista se aborda la necesidad de pensar un nuevo orden mundial, a propósito de la crisis económica reciente. El sentido de este tipo de documentos en una revista de investigación es presentar textos que contextualicen la actividad investigativa internacional. La entrevista fue traducida para magis por Fernando García, doctorando de la Universidad Libre de Berlín. ...
Lázaro del Campo, Paula; Ortega Lobete, Olga
2016-01-01
Presentamos un estudio retrospectivo y observacional que incluye una cohorte de pacientes con SDRA ingresados a lo largo de dos años en el Servicio de Medicina Intensiva del Hospital Clínico Universitario de Valladolid. Todos ellos fueron diagnosticados de SDRA según los criterios de la definición de Berlín y necesitaron intubación orotraqueal y/o traqueotomía con asistencia respiratoria a presión positiva mediante ventilación mecánica con conexión a respirador volumétrico. ...
Parameterized center manifold for unfolding bifurcations with an eigenvalue +1 in n-dimensional maps
Wen, Guilin; Yin, Shan; Xu, Huidong; Zhang, Sijin; Lv, Zengyao
2016-10-01
For the fold bifurcation with an eigenvalue +1, there are three types of potential solutions from saddle-node bifurcation, transcritical bifurcation and pitchfork bifurcation. In the existing analysis methods for high maps, there is a problem that for the fold bifurcation, saddle-node bifurcation and transcritical bifurcation cannot be distinguished by the center manifold without bifurcation parameter. In this paper, a parameterized center manifold has been derived to unfold the solutions of the fold bifurcation with an eigenvalue +1, which is used to reduce a general n-dimensional map to one-dimensional map. On the basis of the reduced map, the conditions of the fold bifurcations including saddle-node bifurcation, transcritical bifurcation and pitchfork bifurcation are established for general maps, respectively. We show the applications of the proposed bifurcation conditions by three four-dimensional map examples to distinguish saddle-node bifurcation, transcritical bifurcation and pitchfork bifurcation.
Invariant Measures for Cherry Flows
Saghin, Radu; Vargas, Edson
2013-01-01
We investigate the invariant probability measures for Cherry flows, i.e. flows on the two-torus which have a saddle, a source, and no other fixed points, closed orbits or homoclinic orbits. In the case when the saddle is dissipative or conservative we show that the only invariant probability measures are the Dirac measures at the two fixed points, and the Dirac measure at the saddle is the physical measure. In the other case we prove that there exists also an invariant probability measure supported on the quasi-minimal set, we discuss some situations when this other invariant measure is the physical measure, and conjecture that this is always the case. The main techniques used are the study of the integrability of the return time with respect to the invariant measure of the return map to a closed transversal to the flow, and the study of the close returns near the saddle.
Invariant measures for Cherry flows
Saghin, Radu
2011-01-01
We investigate the invariant probability measures for Cherry flows, i.e. flows on the two-torus which have a saddle, a source, and no other fixed points, closed orbits or homoclinic orbits. In the case when the saddle is dissipative or conservative we show that the only invariant probability measures are the Dirac measures at the two fixed points, and the Dirac measure at the saddle is the physical measure. In the other case we discuss some situations when there exists another invariant measure supported on the quasi-minimal set, which is the physical measure, and conjecture that this is always the case. The main techniques used are the study of the integrability of the return time with respect to the invariant measure of the return map to a closed transversal to the flow, and the study of the close returns near the saddle.
Resurgence in quantum field theory: nonperturbative effects in the principal chiral model.
Cherman, Aleksey; Dorigoni, Daniele; Dunne, Gerald V; Ünsal, Mithat
2014-01-17
We explain the physical role of nonperturbative saddle points of path integrals in theories without instantons, using the example of the asymptotically free two-dimensional principal chiral model (PCM). Standard topological arguments based on homotopy considerations suggest no role for nonperturbative saddles in such theories. However, the resurgence theory, which unifies perturbative and nonperturbative physics, predicts the existence of several types of nonperturbative saddles associated with features of the large-order structure of the perturbation theory. These points are illustrated in the PCM, where we find new nonperturbative "fracton" saddle point field configurations, and suggest a quantum interpretation of previously discovered "uniton" unstable classical solutions. The fractons lead to a semiclassical realization of IR renormalons in the circle-compactified theory and yield the microscopic mechanism of the mass gap of the PCM.
Monitoring Weather Station Fire Rehabilitation Treatments: Hanford Reach National Monument
US Fish and Wildlife Service, Department of the Interior — The Weather Station Fire (July, 2005) burned across 4,918 acres in the Saddle Mountain Unit of the Hanford Reach National Monument, which included parts of the...
A Genealogy of Convex Solids Via Local and Global Bifurcations of Gradient Vector Fields
Domokos, Gábor; Holmes, Philip; Lángi, Zsolt
2016-12-01
Three-dimensional convex bodies can be classified in terms of the number and stability types of critical points on which they can balance at rest on a horizontal plane. For typical bodies, these are non-degenerate maxima, minima, and saddle points, the numbers of which provide a primary classification. Secondary and tertiary classifications use graphs to describe orbits connecting these critical points in the gradient vector field associated with each body. In previous work, it was shown that these classifications are complete in that no class is empty. Here, we construct 1- and 2-parameter families of convex bodies connecting members of adjacent primary and secondary classes and show that transitions between them can be realized by codimension 1 saddle-node and saddle-saddle (heteroclinic) bifurcations in the gradient vector fields. Our results indicate that all combinatorially possible transitions can be realized in physical shape evolution processes, e.g., by abrasion of sedimentary particles.
Energy Technology Data Exchange (ETDEWEB)
Grebogi, C.; Yorke, J.A.
1993-01-01
Very brief summaries are given of work on the following topics: prevalence, border crossing bifurcations, numerical procedure for computing the dimension, generalized saddle straddle trajectories methods, and finding typical trajectories numerically.
Energy Technology Data Exchange (ETDEWEB)
Grebogi, C.; Yorke, J.A.
1993-01-01
Very brief summaries are given of work on the following topics: prevalence, border crossing bifurcations, numerical procedure for computing the dimension, generalized saddle straddle trajectories methods, and finding typical trajectories numerically.
U.S. Geological Survey, Department of the Interior — Prior to removal of pest species from an area, resource managers must determine if re-immigration from another population is possible. Voles inhabiting Saddle Rock...
Killer whale morphology - Variation in morphology of killer whale ecotypes
National Oceanic and Atmospheric Administration, Department of Commerce — We are using elliptic Fourier analysis to determine the patterns of variation in morphology of dorsal fin shape, saddle patch shape, and eye patch shape of resident,...
Freeman, Mary C.; Freeman, B.J.; Burkhead, N.M.; Straight, C.A.
2008-01-01
Percina crypta, the Halloween Darter, is described as a new species endemic to the Chattahoochee and Flint River systems in Georgia and Alabama. Percina crypta differs from sympatric Percina nigrofasciata in having narrowly separated dorsal saddles (inter-saddle spaces typically less than or equal to saddle width, compared to frequently wider than saddle width in P. nigrofasciata), in usually possessing a single modified scale between the pelvic bases (compared to two or more in P. nigrofasciata), and in having dark wide bands on pectoral-fin rays (versus pectoral fin clear, or with irregular dark marks or weak tessellations on fin rays in P. nigrofasciata). Phylogenetic relationships of P. crypta to other species of Percina are obscure. Percina crypta occurs in shoal and riffle habitats in the Chattahoochee and Flint River mainstems and in a few tributary systems, with the known extant range comprising four disjunct areas separated by mainstem impoundments and altered river reaches.
Confining rigid balls by mimicking quadrupole ion trapping
Fan, Wenkai; Wang, Sihui; Zhou, Huijun
2016-01-01
The rotating saddle not only is an interesting system that is able to trap a ball near its saddle point, but can also intuitively illustrate the operating principles of quadrupole ion traps in modern physics. Unlike the conventional models based on the mass-point approximation, we study the stability of a ball in a rotating-saddle trap using rigid-body dynamics. The stabilization condition of the system is theoretically derived and subsequently verified by experiments. The results are compared with the previous mass-point model, giving large discrepancy as the curvature of the ball is comparable to that of the saddle. We also point out that the spin angular velocity of the ball is analogous to the cyclotron frequency of ions in an external magnetic field utilized in many prevailing ion-trapping schemes.
Multiscale Gentlest Ascent Dynamics
Zhou, Xiang
2016-01-01
The gentlest ascent dynamics (E and Zhou in {\\it Nonlinearity} vol 24, p1831, 2011) locally converges to a nearby saddle point with one dimensional unstable manifold. Here we present a multiscale gentlest ascent dynamics for stochastic slow-fast systems in order to compute saddle point associated with the effective dynamics of the slow variable. Such saddle points, as the candidates of transition states, are important in non-equilibrium transitions for the coarse-grained slow variables; they are also helpful to explore free energy surface. We derive the expressions of the gentlest ascent dynamics for the averaged system, and propose the multiscale numerical methods to efficiently solve the multiscale gentlest ascent dynamics for search of saddle point. The examples of stochastic ordinary and partial differential equations are presented to illustrate the performance of this multiscale gentlest ascent dynamics.
Analysis and experiment of a vessels shell cover in submarine structure
Institute of Scientific and Technical Information of China (English)
ZHANG Yu-li; ZENG Guang-wu
2004-01-01
This paper aims to achieve analysis and experiment results that relate to mechanics capability and structural parameter of a special saddle shell of revolution. Theoretically speaking, the saddle shell of revolution consists of a toroidal shell and a spherical shell. The shells simultaneous equations can be solved with harmonious terms. Where, the fundamental equations can be solved by asymptotic exponential perturbation method. The equations of special solution can be solved by Hovozhilovs special solution. This new idea is from a study of some existing solutions of the toroidal shell. The results have been proved by compared with some experimental results. The experiments aims to study the effect caused by change of material parameter, or by change of different geometric dimensions of the saddle shell, which include the change of thickness, the change of radius of shell, and the change of ribs. Finally, the accepted product of the saddle shell were reinforced by a toroidal rib has been submitted.
Fiscal Policy under Indeterminacy and Tax Evasion
DEFF Research Database (Denmark)
Busato, Francesco; Chiarini, Bruno; Marchetti, Enrico
This paper shows under indeterminacy and tax evasion, an increase in corporate,labor or income tax rates pushes the economy into an expansionary pattern.These effects are reversed when the steady state is saddle-path stable....
On the sufficiency of the linear maximum principle
DEFF Research Database (Denmark)
Vidal, Rene Victor Valqui
1987-01-01
Presents a family of linear maximum principles for the discrete-time optimal control problem, derived from the saddle-point theorem of mathematical programming. Some simple examples illustrate the applicability of the main theoretical results...
Boustany, R.G.
2002-01-01
Review of: Green engineering: Environmentally conscious design / David T. Allen and David R. Shonnard / Prentice-Hall, Inc., One Lake Street, Upper Saddle River, NJ 07458. 2002. 552 pages. ISBN 0-13-061908-6.
Freifelder, R.; Prakash, M.; Alexander, John M.
1986-02-01
We examine the application of transition-state theory for fission-fragment angular distributions to composite nuclei near the limits of stability. The possible roles of saddle-point and scission-point configurations are explored. For many heavy-ion reactions that involve large angular momenta, the observed anisotropies are between the predictions of the saddle-point and scisson-point models. Empirical correlations are shown between the effective moments of inertia and the spin and {Z 2}/{A} of the compound nucleus. These correlations provide evidence for a class of transition-state nuclei intermediate between saddle- and scission-point configurations. An important indication of these patterns is that the speed of collective deformation toward fission may well be slow enough to allow for statistical equilibrium in the tilting mode even for configurations well beyond the saddle point.
Acute aortic occlusion as an unusual embolic complication of cardiac myxoma
Institute of Scientific and Technical Information of China (English)
ZHANG Jian; DUAN Zhi-quan; WANG Chuan-jiang; SONG Qing-bin; LUO Ying-wei; XIN Shi-jie
2006-01-01
@@ Acute aortic occlusion is an infrequent but dangerous vascular emergency with a mortality rate of 50%,1 resulting from aortic saddle embolus, thrombosis of an atherosclerotic abdominal aorta, or sudden thrombosis of a small abdominal aortic aneurysm.
Using Machine Learning to Determine United States Army Readiness at the Battalion Level
2012-02-16
Unit Performance. US Army Research Institute for the Behavioral and Social Sciences, Alexandria, VA, July, 1994. Norvig , Peter, Paradigms of...Russell, Stuart, and Norvig , Peter, Artificial Intelligence, A Modern Approach, Prentice Hall, Upper Saddle River, New Jersey, 1995. Schaffer
Selections from The Handan Dream%英译《邯郸记》选场(四)
Institute of Scientific and Technical Information of China (English)
汪榕培
2001-01-01
@@ Scene Ten Taking a Provincial Office (Enter Miss Cui, followed by Meixiang ) Miss Cui: ( To the tune of Qiniangzi ) Number-One Scholar for three years, The pretty saddle he rode on comes to my mind.
On super efficiency in set-valued optimization
Institute of Scientific and Technical Information of China (English)
LI Tai-yong; XU Yi-hong
2009-01-01
The set-valued optimization problem with constraints is considered in the sense of super efficiency in locally convex linear topological spaces. Under the assumption of iccone-convexlikeness, by applying the seperation theorem, Kuhn-Tucker's, Lagrange's and saddle points optimality conditions, the necessary conditions are obtained for the set-valued optimization problem to attain its super efficient solutions. Also, the sufficient conditions for Kuhn-Tucker's, Lagrange's and saddle points optimality conditions are derived.
INTEGRABILITY AND LINEARIZABILITY FOR A CLASS OF CUBIC KOLMOGOROV SYSTEMS
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
The integrability and linearizability for a class of cubic Kolmogorov systems are studied. A recursive formula to compute the saddle quantities of the systems is deduced firstly, and integrable conditions for the systems are obtained. Then a recursive formula to compute the coefficients of the normal form for saddle points of the systems is also applied. Finally linearizable conditions of the origin for the systems are given. Both formulas to find necessary conditions are all linear and readily done using c...
具有V-不变凸的多目标规划的另一种方法%Another Approach to Multiobjective Programming Problems with V-invex Functions
Institute of Scientific and Technical Information of China (English)
刘三明; 冯恩民; 李小申
2005-01-01
In this paper, optimality conditions for multiobjective programming problems having V-invex objective and constraint functions are considered. An equivalent multiobjective programming problem is constructed by a modification of the objective function.Furthermore, a (α, η)-Lagrange function is introduced for a constructed multiobjective programming problem, and a new type of saddle point is introduced. Some results for the new type of saddle point are given.
Another Approach to Multiobjective Programming Problems with V-invex Functions
Institute of Scientific and Technical Information of China (English)
LIUSan-ming; FENGEn-min; LIXiao-shen
2005-01-01
In this paper, optimality conditions for multiobjective programming problems having V-invex objective and constraint functions are considered. An equivalent multiobjective programming problem is constructed by a modification of the objective function.Furthermore, a (α, η)-Lagrange function is introduced for a constructed multiobjective programming problem, and a new type of saddle point is introduced. Some results for the new type of saddle point are given.
On large N solution of ABJM theory
Energy Technology Data Exchange (ETDEWEB)
Suyama, Takao, E-mail: suyama@phya.snu.ac.k [Center for Theoretical Physics, Seoul National University, Seoul 151-747 (Korea, Republic of)
2010-07-21
We investigate the large N limit of the expectation value W(lambda) of a BPS Wilson loop in ABJM theory, using an integral expression of the partition function obtained recently by Kapustin et al. Certain saddle-point equations provide the correct perturbative expansion of W(lambda). The large lambda behavior of W(lambda) is also obtained from the saddle-point equations. The result is consistent with AdS/CFT correspondence.
Energies, fine structures and transition wavelengths of the core-excited states in Be * ions
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
The fine structures of doubly excited resonances of lithium-like beryllium are calculated using the saddle-point and saddle-point complex-rotation methods. A restricted variational method is used to obtain a more accurate value for the nonrelativistic energy. Relativistic and mass polarization corrections to the resonance energy are included. Transition wavelengths are also calculated and compared with other theories and experimental results.
Converting transient chaos into sustained chaos by feedback control
Lai, Ying-Cheng; Grebogi, Celso
1994-02-01
A boundary crisis is a catastrophic event in which a chaotic attractor is suddenly destroyed, leaving a nonattracting chaotic saddle in its place in the phase space. Based on the controlling-chaos idea [E. Ott, C. Grebogi, and J. A. Yorke, Phys. Rev. Lett. 64, 1196 (1990)], we present a method for stabilizing chaotic trajectories on the chaotic saddle by applying only small parameter perturbations. This strategy enables us to convert transient chaos into sustained chaos, thereby restoring attracting chaotic motion.
DEFF Research Database (Denmark)
Silver, Jeremy D; Ritchie, Matthew E; Smyth, Gordon K
2009-01-01
is developed for exact maximum likelihood estimation (MLE) using high-quality optimization software and using the saddle-point estimates as starting values. "MLE" is shown to outperform heuristic estimators proposed by other authors, both in terms of estimation accuracy and in terms of performance on real data....... The saddle-point approximation is an adequate replacement in most practical situations. The performance of normexp for assessing differential expression is improved by adding a small offset to the corrected intensities....
Llinas’ Phase Reset Mechanism Delays the Onset of Chaos in Shark and Dolphin Wall Turbulence
2014-02-10
has potential application to tornado path management. Shark and dolphin skins are major targets of reverse engineering mechanisms of drag and noise...slightly tilted, near- wall (mushroom) vortex pairs (4d) as a nonlinear pendulum , where the saddle "s", a point of neutral equilibrium, oscillates. The...slanted, e: Schematic of nonlinear pendulum behavior ofvorticity diffusion; phase: (s: saddle, unstable 180°) and foci (f: stable, 0°). f (Upper
Non-Orthogonal Iris Segmentation
2005-05-09
Gonzalez , Rafael C., R. E. Woods, and Steven L. Eddins. Digital Image Processing using MATLAB. Upper Saddle River, New Jersey: Prentice Hall, 2004... images . Over the last ten years, algorithms used to digitize and process biometric signals have been enhanced to increase both accuracy over repeated...Steven L. Eddins. “ Digital Image Processing using MATLAB.” Prentice Hall, Upper Saddle River, NJ. 20044. [15] A. J. Bron, R. C. Tripathi, and B. J
Three-dimensional vortex structures under breaking waves
WATANABE Yasunori; Saeki, Hiroshi; Hosking, Roger J.
2005-01-01
The large-scale vortex structures under spilling and plunging breakers are investigated, using a fully three-dimensional large-eddy simulation (LES). When an overturning jet projecting from the crest in a breaking wave rebounds from the water surface ahead, the vorticity becomes unstable in a saddle region of strain between the rebounding jet and a primary spanwise vortex, resulting in spanwise undulations of the vorticity. The undulations are amplified on a braid in this saddle region, leadi...
Dynamical Behaviour of a Time Delay Model of the ERK and STAT5 Interaction
Directory of Open Access Journals (Sweden)
Kotev V.
2007-12-01
Full Text Available In this paper we have done sensitive analysis of a time delay model which describes the ERK and STAT5 interaction. The results show that the type of the equilibrium point of the model can be a compound saddle-focus or a compound saddle-knot. This means that the model is structurally unstable. From the biological point of view in case of interactions between ERK and STAT the proto-oncogenes may turn into oncogenes.
Resurgence and Dynamics of O(N) and Grassmannian Sigma Models
Dunne, Gerald V
2015-01-01
We study the non-perturbative dynamics of the two dimensional ${O(N)}$ and Grassmannian sigma models by using compactification with twisted boundary conditions on $\\mathbb R \\times S^1$, semi-classical techniques and resurgence. While the $O(N)$ model has no instantons for $N>3$, it has (non-instanton) saddles on $\\mathbb R^2$, which we call 2d-saddles. On $\\mathbb R \\times S^1$, the resurgent relation between perturbation theory and non-perturbative physics is encoded in new saddles, which are associated with the affine root system of the ${\\frak o}(N) $ algebra. These events may be viewed as fractionalizations of the 2d-saddles. The first beta function coefficient, given by the dual Coxeter number, can then be intepreted as the sum of the multiplicities (dual Kac labels) of these fractionalized objects. Surprisingly, the new saddles in $O(N)$ models in compactified space are in one-to-one correspondence with monopole-instanton saddles in $SO(N)$ gauge theory on $\\mathbb R^3 \\times S^1$. The Grassmannian sig...
Directory of Open Access Journals (Sweden)
Comité Editorial
1985-12-01
Full Text Available Woodward, W.R. & Ash, M.G., eds. (1982, The problematic science: Psychology in nineteenth-century thought, Nueva York: Praeger (Praeger Special Studies, XX+ 390 pgs.Mecacci. L. ( 19H5 . Hadiografía del cerebro. Barcelona: Ariel. trad. del italiano. 174 pgs.Ash, M. G. • & Geuter, U.; eds. (1985, Geschichte der deutschen Psychologie im 20. Jahrhundert. Ein Uberblick (Historia de la psicología alemana en el siglo veinte. Una panorámica. Opladen: Westdeutscher Verlag, 386 pgs.Graumann, C.F., ed. (1985, Psychologie im Nationalsozialismus (La psicología durante el nacionalsocialismo . Berlín - Heidelberg - New York - Tokio: Springer- Verlag, 318 pgs.Thomas, H. & Maddox. G. L. eds. (1982 , .New perspectives on old age. A message to decision makers. New York: Springer Publishing Company. XII 146pgs.Sahakian. W.S. (19K2. Historia v sistemas de la psicología. Madrid: Tecnos. trad. del inglés . 664 pgs.Sprung. L. y Sprung. Helga (1984. Grundlagen der Methodologie und Methodik der Psychologie. Eine Einführung in die Forschungs- und Diagnose methodik für empirisch arbeitende Humanwissenschaftler. Berlín ( RDA: VEB Dcutscher Verlag der Wissenseschaften, 452 pgs.
Bieńkowski, Andrzej O; Orlova-Bienkowskaja, Marina J
2016-10-17
The genus Epitrix Foudras, 1860a has a worldwide distribution. Some species of Epitrix are major pests of potato, tomato, eggplant, tobacco and other plants in North America and Europe. Some pest species have been inadvertently introduced from North America to Europe, from Europe to North America and from both continents to some islands in Atlantic and Pacific oceans. Therefore, a key for the identification of all Holarctic species is necessary for plant quarantine and protection services. We have compiled the key for distinguishing Epitrix from genera that could be confused with it and a key for all Holarctic species of Epitrix with the figures of spermathecae and aedeagi and the checklist with a review of the geographical distribution, host plants and history of invasions. The following species are included: E. abeillei (Bauduer), E. allardii (Wollaston), E. atropae Foudras, E. brevis Schwarz, E. caucasica (Heikertinger), E. cucumeris (Harris), E. dieckmanni (Mohr), E. ermischi (Mohr), E. fasciata Blatchley, E. flavotestacea Horn, E. fuscula Crotch, E. hirtipennis (Melsheimer), E. humeralis Dury, E. intermedia Foudras, E. krali Döberl, E. lobata Crotch, E. muehlei Döberl, E. priesneri (Heikertinger), E. pubescens (Koch), E. ogloblini (Iablokov-Khnzorian), E. robusta Jacoby, E. setosella (Fairmaire), E. similaris Gentner, E. solani (Blatchley), E. subcrinita (LeConte), E. tuberis Gentner, E. warchalowskii (Mohr) and E. papa Orlova-Bienkowskaja.
Directory of Open Access Journals (Sweden)
Canevacci, Massimo
1998-12-01
Full Text Available The author illustrates the application of methodological fetishism to the new «visual goods» and to the «biography» of wealth. Three aspects of current visual communication can be subject to ethnographic scrutiny: the bodywork of a car (of an Opel-Tigra, for example, a wall (such as the Berlín Wall and an inorganic body (such as a metropolitan counterculture. The author aims at the (iissolution of these visual fetishes.En este ensayo se aplica el fetichismo metodológico a los nuevos «bienes-visuales» y a la «biografía» de los bienes. La mirada etnográfica permite analizar tres aspectos de la comunicación visual contemporánea: el cuerpo de un automóvil (Opel-Tigra, el cuerpo de un muro (el de Berlín, el cuerpo inorgánico (una contracultura metropolitana. El objetivo es la disolución de los fetiches visuales.
Los modelos de financiación de las Instituciones de Educación Superior en Alemania
Directory of Open Access Journals (Sweden)
Gabriel Ramírez Torres
2007-09-01
Full Text Available En la actualidad la financiación de las Instituciones de Educación Superior Públicas, IESP, es cada vez más limitado, tanto en países desarrollados, como en países en vías de desarrollo, por esa razón en la mayoría de los países se busca diversificar los ingresos de dichas instituciones. En este trabajo se presentan los modelos de financiación de IESP de un grupo de Estados Federados alemanes, lo que se hace siguiendo una clasificación de que permita agrupar a los mismos de acuerdo a las posiciones de determinadas variables. Los modelos de financiación de las IESP desarrollados son los de Berlín, Brandemburgo, Baden-Württemberg, Baja Sajonia, Bremen, Hamburgo, Hesse y Schleswig-Holstein. Palabras clave: Instituciones Educación Superior Públicas, Alemania, Modelos de Financiación, Presupuesto, Clasificación, Berlín, Brandemburgo, Baden-Württemberg, Baja Sajonia, Bremen, Hamburgo, Hesse y Schleswig-Holstein.
Cement and concrete porosity measurement
Directory of Open Access Journals (Sweden)
Lichtner, B.
1974-03-01
Full Text Available Not availableLa porosidad del hormigón, en la que, por una parte influye, el valor agua/cemento (valor a/c dado previamente, y por otra, está sometida a variaciones según crece la edad del hormigón (1, es de importancia decisiva para el desarrollo de sus propiedades tecnológicas. Las modificaciones de la estructura de los poros pueden intervenir para definir el progreso de la madurez, que se caracteriza por la hidrólisis, hidratación y disposición. Objeto de los análisis efectuados en el Instituto del Vidrio, Cerámica y Aglomerantes de la Universidad Técnica de Berlín y del Centro Federal para Comprobación de Materiales (BAM de Berlín, fueron las mediciones de porosidad en el mortero de cemento y hormigón en función del valor a/c y la edad.
Creativity in action: elegantly simple idea puts firm on international pipeline map
Energy Technology Data Exchange (ETDEWEB)
Podlubny, J.
2002-05-06
A saddle bag-like device, a relatively simple invention to carry weights to hold pipelines stable in wet environments, has catapulted a small Athabasca, Alberta, company to international prominence. The saddle bag is made of 100 per cent non-biodegradable material called geotextile, commonly referred to as road matting. The bags have a life expectancy of 100 years or more, easily outlasting the pipe they protect from shifting. Weighting systems are used on pipelines to achieve the negative buoyancy required to prevent them from floating out of wet ground. They are essential in wide swats of the northern areas where the oil and gas industry operates. The saddle bags replace the traditional concrete weights which have been either bolted down or set on top of the pipe. They were bulky and hard to transport, as well as difficult to place on the pipe. In contrast, the saddle bags are easy to transport and easy to install. Indeed, the production process is portable, so that the weighted saddle bags can be made at the site of the pipeline construction job involved. This makes it easier to do pipeline weighting jobs in cold weather, at remote locations or in spots where considerable travel time is involved in completing projects. Saddle Tech has recently joined forces with the giant in the weighting system world from the United States, CRC-Evans. The U.S. firm is marketing the bags under a trademarked name 'the saddle bag'. The product being used on projects in California, as well as on almost 90 per cent of wetlands pipeline work in Alberta and British Columbia. Production was 17,000 bags in the first year of operation. So far this season, more than 40,000 bags have been made and distributed throughout North America. Plans are afoot to expand and convert the production facility to an automated operation, running 24 hours a day.
Resurgence and dynamics of O(N) and Grassmannian sigma models
Dunne, Gerald V.; Ünsal, Mithat
2015-09-01
We study the non-perturbative dynamics of the two dimensional O( N ) and Grassmannian sigma models by using compactification with twisted boundary conditions on {R}× {S}^1 , semi-classical techniques and resurgence. While the O( N) model has no instantons for N > 3, it has (non-instanton) saddles on {{R}}^2 , which we call 2d-saddles. On {R}× {S}^1 , the resurgent relation between perturbation theory and non-perturbative physics is encoded in new saddles, which are associated with the affine root system of the o( N ) algebra. These events may be viewed as fractionalizations of the 2d-saddles. The first beta function coefficient, given by the dual Coxeter number, can then be intepreted as the sum of the multiplicities (dual Kac labels) of these fractionalized objects. Surprisingly, the new saddles in O( N ) models in compactified space are in one-to-one correspondence with monopole-instanton saddles in SO( N ) gauge theory on {{R}}^3× {S}^1 . The Grassmannian sigma models Gr( N, M ) have 2d instantons, which fractionalize into N kink-instantons. The small circle dynamics of both sigma models can be described as a dilute gas of the one-events and two-events, bions. One-events are the leading source of a variety of non-perturbative effects, and produce the strong scale of the 2d theory in the compactified theory. We show that in both types of sigma models the neutral bion emulates the role of IR-renormalons. We also study the topological theta angle dependence in both the O(3) model and Gr( N, M ), and describe the multi-branched structure of the observables in terms of the theta-angle dependence of the saddle amplitudes, providing a microscopic argument for Haldane's conjecture.
Topological properties of the mean-field ϕ4 model
Andronico, A.; Angelani, L.; Ruocco, G.; Zamponi, F.
2004-10-01
We study the thermodynamics and the properties of the stationary points (saddles and minima) of the potential energy for a ϕ4 mean-field model. We compare the critical energy vc [i.e., the potential energy v(T) evaluated at the phase transition temperature Tc ] with the energy vθ at which the saddle energy distribution show a discontinuity in its derivative. We find that, in this model, vc≫vθ , at variance to what has been found in different mean-field and short ranged systems, where the thermodynamic phase transitions take place at vc=vθ [Casetti, Pettini and Cohen, Phys. Rep. 337, 237 (2000)]. By direct calculation of the energy vs(T) of the “inherent saddles,” i.e., the saddles visited by the equilibrated system at temperature T , we find that vs(Tc)˜vθ . Thus, we argue that the thermodynamic phase transition is related to a change in the properties of the inherent saddles rather than to a change of the topology of the potential energy surface at T=Tc . Finally, we discuss the approximation involved in our analysis and the generality of our method.
MONDian three-body predictions for LISA Pathfinder
Bevis, Neil; Trenkel, Christian; Kemble, Steve
2009-01-01
In previous work it was shown that MOND theories predict anomalously strong tidal stresses near the saddle points of the Newtonian gravitational potential. An analytical examination of the saddle between two bodies revealed a linear and a non-linear solution, valid for the outer and inner regions. Here we present a numerical algorithm for solving the MOND equations. We check the code against the two-body analytical solutions and explore the region transitioning between them. We then develop a a realistic model for the MONDian effects on the saddles of the Sun-Earth-Moon system (including further sources is straightforward). For the Sun-Earth saddle we find that the two-body results are almost unchanged, with corrections increasing from full to new Moon. In contrast, the Moon saddle is an intrinsically three-body problem, but we numerically find a recipe for adapting the two-body solution to this case, by means of a suitable re-scaling and axis re-orientation. We explore possible experimental scenarios for LIS...
On the topology of wall turbulence in physical space
Tardu, Sedat
2017-02-01
The topological features dominating the different sublayers of the near wall turbulence are revisited through direct numerical simulations performed in large computational domains up to the Karman number of 1100. The averages of the invariants of the velocity gradient tensor, conditioned by fixed magnitudes of the velocity components, are adequately performed. In the physical space, the dominating topology in the viscous sublayer is the stable focus stretching cohabiting with the unstable node/saddle/saddle points. The stable and unstable focuses mostly populate the inner layer with equal importance, while the former become predominant in the meso and outer layers. Eddies within the low speed streaks with intense streamwise negative velocity of very high shear stress are located near the zero-discriminant facets. The enstrophy and straining prevails the stable focus stretching and the unstable compressing, respectively. The Eulerian velocity field conditioned by a given topology seen by an observer moving with the local velocity is also considered. It is found that the wall normal velocity marks the stretching line of the unstable saddles and the compressing line of the stable nodes/saddles/saddles. The conditional velocity fields linked to the unstable focuses compressing and stable focuses stretching are closely similar.
Evolution of transonicity in an accretion disc
Ray, A K; Ray, Arnab K.; Bhattacharjee, Jayanta K.
2007-01-01
For inviscid, rotational accretion flows driven by a general pseudo-Newtonian potential on to a Schwarzschild black hole, the only possible fixed points are saddle points and centre-type points. For the specific choice of the Newtonian potential, the flow has only two critical points, of which the outer one is a saddle point while the inner one is a centre-type point. A restrictive upper bound is imposed on the admissible range of values of the angular momentum of sub-Keplerian flows through a saddle point. These flows are very unstable to any deviation from a necessarily precise boundary condition. The difficulties against the physical realisability of a solution passing through the saddle point have been addressed through a temporal evolution of the flow, which gives a non-perturbative mechanism for selecting a transonic solution passing through the saddle point. An equation of motion for a real-time perturbation about the stationary flows reveals a very close correspondence with the metric of an acoustic b...
The transition to chaotic phase synchronization
DEFF Research Database (Denmark)
Mosekilde, E.; Laugesen, J. L.; Zhusubaliyev, Zh. T.
2012-01-01
The transition to chaotic phase synchronization for a periodically driven spiral-type chaotic oscillator is known to involve a dense set of saddle-node bifurcations. By following the synchronization transition through the cascade of period-doubling bifurcations in a forced Ro¨ssler system......, this paper describes how these saddle-node bifurcations arise and how their characteristic cyclic organisation develops. We identify the cycles that are involved in the various saddle-node bifurcations and describe how the formation of multi-layered resonance cycles in the synchronization domain is related...... varying arterial blood pressure. The paper finally discusses how an alternative transition to chaotic phase synchronization may occur in the mutual synchronization of two chaotically oscillating period-doubling systems....
Gupta, Rajesh Kumar; Jeon, Imtak
2015-01-01
We use the techniques of supersymmetric localization to compute the BPS black hole entropy in N=2 supergravity. We focus on the n_v+1 vector multiplets on the black hole near horizon background which is AdS_2 x S^2 space. We find the localizing saddle point of the vector multiplets by solving the localization equations, and compute the exact one loop partition function on the saddle point. Furthermore, we propose the appropriate functional integration measure. Through this measure, the one loop determinant is written in terms of the radius of the physical metric, which depends on the localizing saddle point value of the vector multiplets. The result for the one loop determinant is consistent with the logarithmic corrections to the BPS black hole entropy from vector multiplets.
The case for testing MOND using LISA Pathfinder
Magueijo, Joao
2011-01-01
We quantify the potential for testing MOdified Newtonian Dynamics (MOND) with LISA Pathfinder (LPF), should a saddle point flyby be incorporated into the mission. We forecast the expected signal to noise ratio (SNR) for a variety of instrument noise models and trajectories past the saddle. For standard theoretical parameters the SNR reaches middle to high double figures even with modest assumptions about instrument performance and saddle approach. Obvious concerns, like systematics arising from LPF self-gravity, or the Newtonian background, are examined and shown not to be a problem. We also investigate the impact of a negative observational result upon the free-function determining the theory. We demonstrate that, if Newton's gravitational constant is constrained not be re-normalized by more than a few percent, only very contrived MONDian free-functions would survive a negative result. Finally we scan the structure of all proposed relativistic MONDian theories. We conclude that only the Einstein-Aether formu...
MOND habitats within the solar system
Bekenstein, J; Bekenstein, Jacob; Magueijo, Joao
2006-01-01
MOdified Newtonian Dynamics (MOND) is an interesting alternative to dark matter in extragalactic systems. We here examine the possibility that mild or even strong MOND behavior may become evident well inside the solar system, in particular near saddle points of the total gravitational potential. Whereas in Newtonian theory tidal stresses are finite at saddle points, they are expected to diverge in MOND, and to remain distinctly large inside a sizeable oblate ellipsoid around the saddle point. We work out the MOND effects using the nonrelativistic limit of the T$e$V$e$S theory, both in the perturbative nearly Newtonian regime and in the deep MOND regime. While strong MOND behavior would be a spectacular ``backyard'' vindication of the theory, pinpointing the MOND-bubbles in the setting of the realistic solar system may be difficult. Space missions, such as the LISA Pathfinder, equipped with sensitive accelerometers, may be able to explore the larger perturbative region.
Matrix Quantum Mechanics from Qubits
Hartnoll, Sean A; Mazenc, Edward A
2016-01-01
We introduce a transverse field Ising model with order N^2 spins interacting via a nonlocal quartic interaction. The model has an O(N,Z), hyperoctahedral, symmetry. We show that the large N partition function admits a saddle point in which the symmetry is enhanced to O(N). We further demonstrate that this `matrix saddle' correctly computes large N observables at weak and strong coupling. The matrix saddle undergoes a continuous quantum phase transition at intermediate couplings. At the transition the matrix eigenvalue distribution becomes disconnected. The critical excitations are described by large N matrix quantum mechanics. At the critical point, the low energy excitations are waves propagating in an emergent 1+1 dimensional spacetime.
Spin alignments within the cosmic web: a theory of constrained tidal torques near filaments
Codis, Sandrine; Pogosyan, Dmitry
2015-01-01
The geometry of the cosmic web drives in part the spin acquisition of galaxies. This can be explained in a Lagrangian framework, by identifying the specific long-wavelength correlations within the primordial Gaussian random field which are relevant to spin acquisition. Tidal Torque Theory is revisited in the context of such anisotropic environments, biased by the presence of a filament within a wall. The point process of filament-type saddles represents it most efficiently. The constrained misalignment between the tidal and the inertia tensors in the vicinity of filament-type saddles simply explains the distribution of spin directions. This misalignment implies in particular an azimuthal orientation for the spins of more massive galaxies and a spin alignment with the filament for less massive galaxies. This prediction is found to be in qualitative agreement with measurements in Gaussian random fields and N-body simulations. It relates the transition mass to the geometry of the saddle, and accordingly predicts...
Stabilized Quasi-Newton Optimization of Noisy Potential Energy Surfaces
Schaefer, Bastian; Roy, Shantanu; Goedecker, Stefan
2014-01-01
Optimizations of atomic positions belong to the most commonly performed tasks in electronic structure calculations. Many simulations like global minimum searches or characterizations of chemical reactions require performing hundreds or thousands of minimizations or saddle computations. To automatize these tasks, optimization algorithms must not only be efficient, but also very reliable. Unfortunately computational noise in forces and energies is inherent to electronic structure codes. This computational noise poses a sever problem to the stability of efficient optimization methods like the limited-memory Broyden-Fletcher-Goldfarb-Shanno algorithm. We here present a technique that allows obtaining significant curvature information of noisy potential energy surfaces. We use this technique to construct both, a stabilized quasi-Newton minimization method and a stabilized quasi-Newton saddle finding approach. We demonstrate with the help of benchmarks that both the minimizer and the saddle finding approach are sup...
Mass yields and kinetic energy of fragments from fission of highly-excited nuclei with A≲220
Denisov, V. Yu.; Margitych, T. O.; Sedykh, I. Yu.
2017-02-01
It is shown that the potential energy surface of the two separated fragments has the saddle point, which takes place at small distance between the surfaces of well-deformed fragments. The height of this two-body saddle point is larger than the height of one-body fission barrier for nuclei with A ≲ 220. The mass yields of the fission fragments, which are appearing at the fission of nuclei with A ≲ 220, are related to the number of states of the two-fragment systems at the two-body saddle points. The characteristics of kinetic energy of fragments are described by using the trajectory motion equations with the dissipation terms. The Gaussian distribution of the final kinetic energy around the classical value of this energy induced by the stochastic fluctuations is taken into account at an evaluation of the total kinetic energy distributions of the fission fragments.
Scaling dimensions of monopole operators in the $\\mathbb{CP}^{N_b - 1}$ theory in $2+1$ dimensions
Dyer, Ethan; Pufu, Silviu S; Sachdev, Subir
2015-01-01
We study monopole operators at the conformal critical point of the $\\mathbb{CP}^{N_b - 1}$ theory in $2+1$ spacetime dimensions. Using the state-operator correspondence and a saddle point approximation, we compute the scaling dimensions of the operators that insert one or two units of magnetic flux to next-to-leading order in $1/N_b$. We compare our results to numerical studies of quantum antiferromagnets on two-dimensional lattices with SU($N_b$) global symmetry, using the mapping of the monopole operators to valence bond solid order parameters of the lattice antiferromagnet. For the monopole operators that insert three or more units of magnetic flux, we find that the rotationally-symmetric saddle point is unstable; in order to obtain the scaling dimensions of these operators, even at leading order in $1/N_b$, one should consider non-spherically-symmetric saddles.
Perez-Molina, Manuel; Carretero, L; Acebal, P; Blaya, S
2008-11-01
We rigorously analyze the optical singularities and power flux in the near-field region of the novel superlenses reported in [Science317, 927 (2007)] For this purpose, we derive near-field expressions and a general criterion to classify the optical singularities in the vacuum, which are valid when the (s- or p-polarized) electromagnetic fields are generated by any planar field distribution with Cartesian or azimuthal symmetry. Such general results are particularized to the superlenses [Science317, 927 (2007)], for which we identify a sequence of optical vortices and saddles that arise from evanescent-field interference. While the saddles are always located around the focal region, the vortex locations depend on the source field. The features of the topological connection between vortices and saddles are also discussed.
Periodic and homoclinic orbits in a toy climate model
Directory of Open Access Journals (Sweden)
M. Toner
1994-01-01
Full Text Available A two dimensional system of autonomous nonlinear ordinary differential equations models glacier growth and temperature changes on an idealized planet. We apply standard perturbative techniques from dynamical systems theory to study small amplitude periodic orbits about a constant equilibrium. The equations are put in cononical form and the local phase space topology is examined. Maximum and minimum periods of oscillation are obtained and related to the radius of the orbit. An adjacent equilibrium is shown to have saddle character and the inflowing and outflowing manifolds of this saddle are studied using numerical integration. The inflowing manifolds show the region of attraction for the periodic orbit. As the frequency gets small, the adjacent (saddle equilibrium approaches the radius of the periodic orbit. The bifurcation of the periodic orbit to a stable homoclinic orbit is observed when an inflowing manifold and an outflowing manifold of the adjacent equilibrium cross.
Potsdamer Platz : Experiencia y narración en el caso argentino: 1976-1983
De Diego, José Luis
1996-01-01
Comenzaré —si se me permite— con una referencia autobiográfica. El 20 de enero del `94 dicté una conferencia en el Instituto Latinoamericano de Berlín. Había llegado a la ciudad ese mismo día y conseguir hotel resultó bastante difícil. Además, no era fácil discernir la ubicación del Instituto —Potsdamer Strasse 37— en el enorme mapa que tenía. Finalmente, decidí tomar un S-Bahn que me llevara, a Potsdamer Platz; intuía que el Instituto no estaría lejos de eso que suponía sería una plaza. Subí...
Thomas Sturm, Research Scholar al Max Planck Institute for the History of Science
Mata M., Virginia [Entrevista
2008-01-01
Format com a filòsof, però amb un fort interès per la història de la ciència, Thomas Sturm és un especialista en filosofia moderna i les relacions entre la història i la filosofia de la ciència. Des de 2005 és investigador del "Max Planck Institute for the History of Science", a Berlín, on ha treballat en el projecte "Perceptual Illusions in the Dynamics of Psychological Research". Sturm va visitar el Centre d’Estudis de la Ciència de la UAB (CEHIC), on va oferir una conferència sobre les il·...
Galak, Eduardo
2010-01-01
El presente artículo es un análisis de la película "Tropa de Élite" (2007), ganadora del prestigioso "Oso de oro" ("Goldener Bär"), a la mejor película en el Festival de Cine de Berlín (Berlinale), en el cuál se trabajan principalmente los conceptos "cuerpo" y "policía", y secundariamente los de "educación", "la política" y "lo político". La idea, entonces, es pensar a la policía en un doble sentido: coloquial y académico. A través de los personajes de André Matias y Nascimento se narra las v...
Eduardo Galak
2010-01-01
El presente artículo es un análisis de la película "Tropa de Élite" (2007), ganadora del prestigioso "Oso de oro" ("Goldener Bär"), a la mejor película en el Festival de Cine de Berlín (Berlinale), en el cuál se trabajan principalmente los conceptos "cuerpo" y "policía", y secundariamente los de "educación", "la política" y "lo político". La idea, entonces, es pensar a la policía en un doble sentido: coloquial y académico. A través de los personajes de André Matias y Nascimento se narra las v...
La Formación de la Comunidad de Inteligencia Española: Un proceso en marcha
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Galvache Valero, Francisco
2005-01-01
Full Text Available El fin de la bipolaridad dio lugar a la aparición de nuevos riesgos y amenazas, y en un escenario en el que la globalización había potenciado la interdependencia en los espacios definidos por el binomio seguridad-defensa, lo que imponía la necesidad de cooperación entre aliados, para resolver crisis (que crecían en número y afrontar amenazas de carácter cada vez más transnacional. La invasión de Kwait, preludio de la guerra de Irak, la larga crisis de los Balcanes, y el casi sempiterno conflicto de Oriente Medio, mostraron un potencial desestabilizador no previsible antes de la caída del muro de Berlín.…
Los Ingenieros Geógrafos de México
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Héctor Mendoza Vargas
2002-11-01
Full Text Available Hasta ahora se han conseguido avances significativos en el conocimiento sobre la enseñanza de la Geografía y los procesos de institucionalización, sobre todo, en las universidades europeas, como Berlín (1860-1870, París (1870-1871 y Londres (1886-1887 (Capel, 1988. Con más rezago y no pocas dificultades en la búsqueda de la documentación e interpretación de los papeles han quedado otras experiencias geográficas, también de Europa, pero que su creación y práctica se alejaron de la tradició...
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Gerardo Paz Otero
1965-09-01
Full Text Available Diverso fue y sigue siéndolo, el destino de los dos hermanos Humboldt, Guillermo y Alejandro. Sino que se inicia con el nacimiento: Guillermo, el mayor, nace el 22 de junio de 1767 en Potsdam, residencia de los emperadores prusianos, la ciudad de los palacios imperiales, el imperio del militarismo germano; su cuna se meció cerca al palacete de Sans-Soussi, donde Federico el Grande forja ba el poderío de Prusia, cultivaba las ciencias y las artes, anfitrionaba a los intelectuales de Europa, y era "vasallo espiritual de Volta ire", según la aguda frase de Goethe. Alejandro viene al mundo dos años después (14 de septiembre de 1769 en Berlín, en la casa burguesa de la Jagerstrasse (calle del cazador que su madre Elizabeth von Humboldt heredara de su primer esposo.
Un calco Cervantino: Dios es grande
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Mitja Skubic
1992-12-01
Full Text Available Algunos estudios recientes dedican amplio espacio al aporte arábigo en Cervantes, ocupándose de manera particular de los préstamos sin embargo, parecen descuidar lo relativo a los calcos semánticos. Resulta curiosa comprobar como el estudio fundamental sabre los medias estilísticos en El Quijote de Helmut Hatzfeld (Don Quijote als Wortlamstwerk, Berlín, 1927, no reserva a los calcos un papel adecuado. Tanto más preciosas son las observaciones de Rafael Lapesa sabre arabismos semánticos, tales como: infante, hidalgo, plata yotros (Historia de la lengua española, 7 edic., Madrid, 1968, pp.108y ss.
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Manuel Gárate
2005-02-01
Full Text Available En los últimos días del III Reich, Hitler y sus lugartenientes se encuentran refugiados en un bunker de Berlín. Los soviéticos están a las puertas de la ciudad y el régimen agoniza. Adolfo Hitler prefiere sacrificar a su pueblo antes de enfrentar una nueva capitulación. Los recuerdos de la derrota de 1918 lo obsesionan mientras niños, mujeres y ancianos luchan por sobrevivir a la guerra total desatada por su líder. El relato está construido partir del testimonio real de una joven que trabaj...
Uus sünagoog pani juudid tantsima / Peeter Kuimet, Kaia Otti
Kuimet, Peeter
2007-01-01
Tallinnas Karu tänaval avati 16. mail 2007 uus juudi sünagoog, avamistseremoonial viibisid Iisraeli asepeaminister Shimon Peres, Eesti president Toomas Hendrik Ilves, peaminister Andrus Ansip, Venemaa pearabi Berl Lazar, Iisraeli pearabi Yona Metzger ja sünagoogi suurrahastaja Aleksander Bronshtein. President Toomas Hendrik Ilves viitas oma kõnes paralleelidele eestlaste ja juutide ajaloos. Vt. samas: Juutide usk, kombed ja toit; Sünagoogi avamist kommenteerivad meediaõppejõud Hagi Shein, dirigent Eri Klas. Vt. samas: Peres: elevantide keskel on väikestel raske magada. Ilmunud ka: Postimees : na russkom jazõke 17. mai 2007, lk. 2; Narvskaja Gazeta, 19. mai 2007, lk. 6 (autor Ksenia Repson)
Osmotically driven pipe flows and their relation to sugar transport in plants
DEFF Research Database (Denmark)
Jensen, Kåre Hartvig; Rio, Emmanuelle; Hansen, Rasmus
2009-01-01
driven flows through pipes with semi-permeable walls. Our aim IS to understand the dynamics and structure of a 'sugar front', i.e. the transport and decay of a sudden loading of sugar in a water-filled pipe which is closed in both ends. In the limit of low axial resistance (valid in our experiments...... with the results of Eschrich, Evert & Young (Planta (Berl.), vol. 107, 1972, p. 279). In the opposite case of very narrow channels, we obtain an asymptotic solution for intermediate times showing a decay of the front velocity as M(-1/3)t(-2/3) with time t and dimension less number M similar to eta kappa L(2)r(-3...... only for the short distance transport of sugar in plants....
Cabañas Bravo, Miguel
2011-01-01
Josep Renau (Valencia 1907-Berlín 1982) es, sin duda, uno de los grandes creadores del arte español contemporáneo, pero también uno de sus artistas más singulares, polifacéticos y comprometidos. En ámbitos artístico-culturales muy diferentes, compaginó con clara conciencia y dedicación la pintura, el muralismo, la ilustración, el diseño gráfico y el fotomontaje, conformando una brillante y atractiva trayectoria vital y creativa, que es también la de una progresión. Progresión, por un lado, re...
Steni muinasjutuvõistluse võitjad selgunud / Ants Roos, Ann Roos
Roos, Ants
2008-01-01
Steni XVI muinasjutuvõistluse žüriisse kuulusid: Ann Roos, Ants Roos, Leelo Tungal, Krista Kumberg, Leida Olszak, Ülle Väljataga. Tulemused: I koht Siim Niinelaid, II koht Julius Air Kull, III koht Mihkel Rammu. Žürii eriauhinnad: Anna Kristin Peterson, Elis Ruus, Rain Hallikas, Mariliis Peterson, Marjaliisa Palu, Karl Kirsimäe, Margaret Pulk. Ergutusauhinnad: Karmel Klaus, Martti Kaljuste, Kristina Korell, Mirjam Võsaste, Mihkel Põder, Iirys Kalde, Miriam Jamul, Mari-Ann Mägi, Ketlin Saar, Liisbeth Kirss. Muud eriauhinnad said: Allan Läll, Berle Mees, Anett Kuuse, Karl Erik Kübarsepp, Grete Tamm, Siim Niinelaid, Kaisa Marie Sipelgas, Ellen Anett Põldmaa, Evelin Laul, Karl Laas, Karl Stamm, Kerli Retter
Aulas sin muros: Hacia una casa común educativa
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Fernando BELTRÁN LLAVADOR
2009-11-01
Full Text Available El escritor Julio Llamazares, en el diario £7 Pa/¿(miércoles, 21 de Noviembre de 1990, después de un año de la caída del muro de Berlín, comunicaba a los lectores la nostalgia que sentía «de un muro que durante muchos años dividió a su país y el mundo entero en dos mitades»; naturalmente, no se trataba tan sólo de un sentimiento literario ni de una evocación romántica sino que encontraba su fundamento en las secuelas dolorosas que ese acontecimiento ha ocasionado en las vidas de numerosos colectivos minoritarios: emigrantes turcos, vietnamitas... soldados rusos, etc.
Entre guerra y paz. América Latina frente a la tragedia del primer conflicto mundial
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GRAZIANO PALAMARA
2015-07-01
Full Text Available El presente ensayo propone un análisis de las posturas latinoamericanas ante la Primera Guerra Mundial -Pgm-; la reflexión se fundamenta en un modelo interpretativo, que considera las guerras de alcance mundial, no solo como el punto de disgregación de un sistema internacional, sino como el momento fundante de un nuevo orden. Este modelo permite reflexionar en cuanto a la manera como Latinoamérica se acercó al declive del orden posnapoleónico y la conducta que adoptó, en 1917, al ingresar Estados Unidos al conflicto y la Revolución de Octubre en Rusia, cuando se abrió en el contexto de las relaciones internacionales una nueva época que habría mantenido intactas algunas de sus características, por lo menos hasta la caída del muro de Berlín.
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Jorge Luis Gaete
2011-05-01
Full Text Available La primera mitad del siglo XX estuvo marcada por dos acontecimientos que cambiaron para siempre la estructura internacional, la cual se destacaba por diversos factores, como la exacerbación de los nacionalismos, la búsqueda del poder económico y territorial, por las ideologías que buscaban imperar de diversos Estados, entre varios otros. Estos procesos históricos son conocidos como las “Guerras Mundiales”, que provocaron tales consecuencias que a partir de la segunda mitad del siglo pasado podemos hablar de una nueva configuración del poder mundial, marcado por la polarización entre la ideología comunista de la Unión Soviética y la capitalista de Estados Unidos, siendo triunfante esta última gracias a la caída del muro de Berlín, en la década de los 90...
El Islam en el mundo árabe: respuesta a una globalización excluyente
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Rosa Duro Montealegre
2004-11-01
Full Text Available Desde hace varios siglos la memoria histórica y los clichés han impuesto la visión de un mundo occidental que ha propugnado un estado de ignorancia frente al Islam y a su naturaleza que es difícil cambiar, sobre todo cuando los procesos de ideologización y demonización de la realidad islámica se encuentran con este nuevo orden mundial, establecido tras la caída del muro de Berlín y la disolución del bloque comunista, lo cual, sin duda, configura un panorama geopolítico, destinado a representar los claros intereses de Occidente, en especial Estados Unidos y sus aliados . En este estado de cosas asistimos a un debate en torno a la consideración de los enemigos actualizados que amenazan a este nuevo orden, ya que las disidencias no son admitidas.
Escenarios sobre el orden internacional
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Luis Dallanegra Pedraza
2012-01-01
Full Text Available Luego de las grandes cambios que se dieron con la caída del Muro de Berlín y la desintegración en la URSS, se analizan, desde una perspectiva realista-sistémicaestructural, los componentes que intervienen en la generación del orden mundial, qué factores intervienen y cuáles son las diferentes aspiraciones respecto de las características que debería tener. Se tiene en especial consideración la creciente heterogeneización del sistema y la manera en que actores transnacionales operan como motores del futuro orden, predominando por sobre las posibilidades del actor históricamente dominante: el Estado-Nación. Se estudian las características principales del funcionamiento del sistema internacional y el significado de su marco institucional.
El beato Contardo Ferrini, sabio humanista, romanista y santo
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Julian Motta Salas
1967-11-01
Full Text Available Nació Contardo Ferrini en Módena el año 1859. Estudió en la Universidad de Pavía y esta le otorgó el diploma de doctor en Derecho con una tesis sobre la utilidad que la Historia del Derecho puede derivar de los poemas de Homero y Hesíodo. Como con ese grado hubiese ganado el joven doctor una beca para estudiar en cualquiera universidad extranjera escogió la de Berlín y, habiendo pasado los Alpes en 1880, empezó estudios profundos de Derecho en esa célebre Universidad, ayudados con una aguda inteligencia y con el conocimiento para sus pocos años del griego y del latin, indispensables para cualquier disciplina del pensamiento, ora en las letras, en las ciencias, ora en los estudios del Derecho.
Patrones temporales de comportamiento táctico en carreras atléticas de 5.000 metros
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Daniel Lapresa Ajamil
2012-09-01
Full Text Available El comportamiento táctico en carreras atléticas de fondo ha sido residualmente estudiado. En el presente trabajo, en el seno de la metodología observacional, se ha construido un instrumento de observación que permite detectar patrones temporales de comportamiento táctico –mediante el software Theme, versión 5.0.–, en el muestreo observacional correspondiente a las finales de: Campeonatos Mundiales París 2003 y Berlín 2009; Olimpiadas de Atenas 2004 y Pekín 2008; Campeonatos Europeos de Goteborg 2006 y Barcelona 2010, en la modalidad de 5000 metros –categoría masculina–. Los resultados obtenidos muestran pautas comportamentales relevantes, relativas, fundamentalmente, al ritmo de la prueba y a la interacción del atleta ganador con sus competidores.
Cramer, Thomas; Molano, Juan Carlos; Öcal, Ali Duran
2011-01-01
El análisis geocientífico de mármoles usados en la antigüedad griega y romana ayuda a resolver problemas arqueológicos. En el presente trabajo se muestran métodos usados en la caracterización de hallazgos de mármol de Asia Menor que hoy se encuentran en el Museo de Pérgamo en Berlín. 232 muestras de 39 objetos antiguos y 362 muestras de 20 yacimientos de mármol dieron una base de datos amplia. La frecuente superposición de características de los yacimientos requiere un enfoque multivariado. P...
Saint-Dizier, Francis
2016-01-01
Alos cincuenta años de la creación del Instituto Cubano de Arte e Industria Cinematográfica (ICAIC), esta edición de la revista vuelve ampliamente sobre los efectos políticos y estéticos que produjo la revolución cubana en las historias de los cines en América Latina. Las películas producidas y realizadas por el instituto cubano, a partir de 1959 hasta la caída del muro de Berlín, trasladan a imagen la épica popular, construyen una representación de la insurrección nacional, dibujan una ética...
infantil nos processos de construção do self
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Tamara Grigorowitschs
2010-01-01
Full Text Available El artículo aborda, desde una perspectiva sociológica, el papel del juego en los procesos de socialización infantil y de la formación del self en la infancia, recurriendo a autores clásicos como Walter Benjamin y Georg Herbert Mead y de algunos de sus intérpretes contemporáneos, como Gunter Gebauer y Christoph Wulf, autores que organizaron esa discusión en torno del concepto de mimesis. Presenta también un análisis de dos "imágenes" presentes en La infancia en Berlín alrededor de 1900, de autoría de Walter Benjamín, que retratan de forma autobiográfica el papel del juego para la formación del self en la infancia.
Janusz Korczak, un inescuchado testimonio de esperanza
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Bruno M. BELLERATE
2010-03-01
Full Text Available RESUMEN: Henryk Goldszmit, éste era su verdadero nombre y apellido, había nacido en Varsovia el 22 de julio de 1878 ó 1879 (año incierto, debido al descuido en presentarlo en el Registro civil, de padre judío, abogado conocido y de madre católica. Gozó de una vida acomodada, sin descompensaciones ni preocupaciones, ni siquiera perturbada por interrogantes derivados de su educación religiosa, prácticamente hasta la muerte de su padre (1896 por locura. Este hecho lo trastornó profundamente y modificó su vida, no sólo desde el punto de vista económico. Entre mil dificultades logró doctorarse en medicina y especializarse después en Berlín con estancias en París y Londres.
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José Manuel Sánchez Muñoz
2011-10-01
Full Text Available En el mes de noviembre de 1859, durante la presentación mensual de losinformes de la Academia de Berlín, el alemán Bernhard Riemann presentóun trabajo que cambiaría los designios futuros de la ciencia matemática. El tema central de su informe se centraba en los números primos, presentando el que hoy día, una vez demostrada la Conjetura de Poincaré, puede ser considerado el problema matemático abierto más importante. El presente artículo muestra en su tercera sección una traducción al castellano de dicho trabajo.
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Lothar Sprung
1986-12-01
Full Text Available El libro de Ebbinghaus, Uber das Gediichtnis: Untersuchungen zur experimentellen Psychologie, constituye la Partida de nacimiento de la psicofísica de los procesos psicológicos superiores. El presente es un artículo en homenaje al distinguido científico alemán, cuya contribución se hizo presente en la investigación de la memoria, de la inteligencia infantil, además de haber fundado laboratorios de psicología experimental en Berlín, Breslau y Halle. El importante zeitschrift für Psychologie und Physiologie der Sinnesorgane fue fundado por él en 1890.
1923. Theo Van Doesburg y el pensamiento abstracto en el proyecto arquitectónico
Jiménez Sequeiros, José Luis
2016-01-01
En 1923 se suceden en Europa tres acontecimientos culturales trascendentales para la comprensión de la evolución de la arquitectura del siglo XX: la primera exposición de los trabajos de la Escuela Bauhaus en Weimar, la Gran Exposición de Arte en Berlín y la exposición de los arquitectos de De Stijl en la galería L’Effort Moderne de París. En ellas se presentan los trabajos conclusivos de diez años de evolución del arte abstracto que, desde la Primera Acuarela Abstracta de Vasili Kandinski, d...
What is Happening to Corporations and What of Their Future?
DEFF Research Database (Denmark)
Thompson, Grahame
2012-01-01
The chapter analyzes the mergent ways companies are becoming overtly political actors and pursues the consequences of this for the future of the corporation. The discussion begins by analyzing the relationships between owners and shareholders in the context of the legal constitution of corporations....... The chapter moves on to take up ‘the debate’ about the divorce of ownership from control in the light of this thorough examination of the legal status of the corporation, in so doing revisiting the terms of that debate in the 1930s and 1940s that arose in the light of the Berle and Means’ book, The Modern...... Corporation and Private Property(1932). Subsequent to this it moves on to think about the possible future of the corporation and the potential for the reform of corporate governance in this light of current circumstances and trends in a post-crisis world....
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André Gounot
2005-01-01
Full Text Available Los archivos del KOMINTERN en el Centro Ruso de Conservación y Estudio de los Documentos sobre la Historia Contemporánea (CRCRHC de Moscú, recientemente abiertos para el estudio científico, nos ofrecen fuentes documentales fundamentales para entender el desarrollo de la Internacional Deportiva Roja (IDR como una de las organizaciones auxiliares del citado KOMINTERN. Las referidas fuentes documentales han aportado nuevas informaciones y datos sobre la creación en España en 1931, con el establecimiento de la 2ª República, de la Federación Cultural y Deportiva Obrera (FCDO, organización que en 1934 se adhiere a la Internacional Deportiva Roja (IDR, siendo el embrión del nacimiento del Comité Catalán pro Deporte Popular que presentaría el proyecto de la Olimpiada Popular de Barcelona de 1936 como alternativa a la Olimpiada de Berlín de 1936 de Hitler. Por otra parte la Internacional Deportiva Roja (IDR creó a finales de 1935 el Comité Internacional para la defensa de la Idea Olímpica, cuyo objetivo era coordinar los movimientos de oposición a los Juegos de Berlín. También la propia Federación Cultural y Deportiva Obrera (FDCO fundó en 1936 el Comité Español de Defensa del Espíritu Olímpico con este mismo fin. La Olimpiada Popular de Barcelona de 1936 permitió entre otras cosas expresar la nueva alianza entre Comunismo y Olimpismo, construida con discursos contradictorios apoyándose en el universalismo, la paz y la igualdad de razas.
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Diana Míguez Carames
2011-05-01
Full Text Available El objetivo de este trabajo fue caracterizar la toxicidad de los sedimentos de una zona del Río Uruguay, aplicando una batería de bioensayos. Las muestras provinieron de: una zona de influencia de descargas domésticas y efluentes de una planta de celulosa (Fray Bentos, una ciudad turística aguas abajo (Las Cañas y otra aguas arriba (Nuevo Berlín, sin influencia directa de dichos vertidos. Los bioensayos aplicados en elutriados fueron: de toxicidad con Photobacterium leiognathi, de reproducción con Ceriodaphnia dubia, de teratogenicidad y letalidad con Pimephales promelas y el ensayo sub-letal en sedimento completo con Hyalella curvispina. Para evaluar la biodisponibilidad y las rutas de toxicidad, se midió el fraccionamiento del 2,4,5-triclorofenol, con resultados: 63% disuelto, 27% adsorbido sobre partículas y el resto sedimentado.Se observó toxicidad por orgánicos y metales con P. leioghnati para todos los sitios. La frecuencia de malformaciones vertebralesde P. promelas fue de 3.3% en Fray Bentos, pero C. dubia sólo mostró efectos en Nuevo Berlín y Las Cañas. Los efectos con H. curvispina se evidenciaron en todas las muestras. Las rutas de toxicidad incluirían la ingestión de contaminantes disueltos y particulados asociados a arcillas y limo. El vínculo causa-efecto para la toxicidad se continuará investigando.
Organização empresarial em Alfred Marshall
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Jaques Kerstenetzky
2004-06-01
Full Text Available Encontra-se na obra de Marshall uma abordagem ao ambiente empresarial que difere de sua tradicionalmente considerada contribuição à economia. Embora Marshall seja o fundador da vertente do equilíbrio parcial da microeconomia, seu trabalho no tema da organização empresarial é muito mais rico do que esta contribuição específica. O artigo explora a análise de cunho histórico e institucional desenvolvida por Marshall no tema da firma, dos mercados e dos ambientes empresariais. Como resultado, sugere que Marshall pode ser apontado como precursor de abordagens contemporâneas ao tema, como a abordagem das capacitações organizacionais, e da grande corporação americana, de autores como Berle e Means e Chandler.We can find in Marshall’s works an approach to business environments that is different from his traditionally accepted contribution to mainstream economics. Though Marshall is indeed the founder of the partial equilibrium analysis branch of traditional microeconomics, his work on the theme of business is much richer than his specific contribution to microeconomics. The article explores Marshall's institutional and historical analysis of firms, markets and of business environments. As an outcome, it suggests that Marshall can be pointed out as a forerunner of modern approaches to the theme, like Berle and Means’s and Chandler’s works on corporations, and the capabilities approach to the theory of the firm.
DEFF Research Database (Denmark)
Markvorsen, Steen
2007-01-01
We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$.......We consider a specific function of two variables whose graph surface resembles a blue lagoon. The function has a saddle point $p$, but when the function is restricted to any given straight line through $p$ it has a {\\em{strict local minimum}} along that line at $p$....
A unified kinetic approach to binary nucleation
Energy Technology Data Exchange (ETDEWEB)
Kevrekidis, P.G. [Department of Physics, Rutgers University, 136 Frelinghuysen Road]|[E.O.H.S.I., Rutgers University]|[UMDNJ, 170 Frelinghuysen Road, Piscataway, New Jersey 08854-8019 (United States); Lazaridis, M. [Norwegian Institute for Air Research (NILU), Instittutvein 18, P. O. Box 100, N-2007 Kjeller (Norway); Drossinos, Y. [European Commission, Joint Research Centre, I-21020 Ispra (Vatican City State, Holy See) (Italy); Georgopoulos, P.G. [E.O.H.S.I., Rutgers University]|[UMDNJ, 170 Frelinghuysen Road, Piscataway, New Jersey 08854 (United States)
1999-11-01
Two different methods to calculate the steady-state nucleation rate in heteromolecular systems proposed by Stauffer (1976) and Langer (1969) are analyzed. Their mathematical equivalence is explicitly demonstrated, thereby obtaining a generic expression for the rate of binary nucleation. Its numerical evaluation does not entail rotation of the coordinate system at the saddle point, but it only requires data in the natural coordinate system of number fluctuations, namely molecular impingement rates, the droplet free energy and its second order derivatives at the saddle point, and the total density of condensible vapors. {copyright} {ital 1999 American Institute of Physics.}
Bifurcation control in the Burgers-KdV equation
Energy Technology Data Exchange (ETDEWEB)
Maccari, Attilio [Technical Institute ' G. Cardano' , Piazza della Resistenza 1, 00015 Monterotondo (Rome) (Italy)], E-mail: solitone@yahoo.it
2008-03-15
We consider the bifurcation control for the forced Burgers-KdV equation by means of delay feedback linear terms. We use a perturbation method in order to find amplitude and phase modulation equations as well as external force-response and frequency-response curves. We observe in the resonance response a saddle-node bifurcation that leads to jump and hysteresis phenomena. We compare the uncontrolled and controlled systems and demonstrate that control terms can delay or remove the occurrence of the saddle-node bifurcation and reduce the amplitude peak of the resonant response.
Dynamic Behaviour of Nanoscale Electrostatic Actuators
Institute of Scientific and Technical Information of China (English)
林文惠; 赵亚溥
2003-01-01
The dynamic behaviour for nanoscale electrostatic actuators is studied.A two parameter mass-spring model is shown to exhibit a bifurcation from the case excluding an equilibrium point to the case including two equilibrium points as the geometrical dimensions of the device are altered.Stability analysis shows that one is a stable Hopf bifurcation point and the other is an unstable saddle point.In addition,we plot the diagram phases,which have periodic orbits around the Hopf point and a homoclinic orbit passing though the unstable saddle point.
No influence of a N=126 Neutron Shell Closure in Fission Fragment Mass Distributions
Chaudhuri, A; Banerjee, K; Bhattacharya, S; Sadhukhan, Jhilam; Kundu, S; Bhattacharya, C; Meena, J K; Mukherjee, G; Saha, A K; Asgar, Md A; Dey, A; Manna, S; Pandey, R; Rana, T K; Roy, P; Roy, T; Srivastava, V; Bhattacharya, P; Biswas, D C; Joshi, B N; Mahata, K; Shrivastava, A; Vind, R P; Pal, S; Behera, B R; Singh, Varinderjit
2015-01-01
Mass distributions of the fragments in the fission of $^{206}$Po and the N=126 neutron shell closed nucleus $^{210}$Po have been measured. No significant deviation of mass distributions has been found between $^{206}$Po and $^{210}$Po, indicating the absence of shell correction at the saddle point in both the nuclei, contrary to the reported angular anisotropy and pre-scission neutron multiplicity results. This new result provides benchmark data to test the new fission dynamical models to study the effect of shell correction on the potential energy surface at saddle point.
Nonlinear behavior for nanoscale electrostatic actuators with Casimir force
Energy Technology Data Exchange (ETDEWEB)
Lin Wenhui [College of Science, China Agricultural University, Beijing 100083 (China); Zhao Yapu [State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080 (China)]. E-mail: yzhao@lnm.imech.ac.cn
2005-03-01
The influence of Casimir force on the nonlinear behavior of nanoscale electrostatic actuators is studied in this paper. A one degree of freedom mass-spring model is adopted and the bifurcation properties of the actuators are obtained. With the change of the geometrical dimensions, the number of equilibrium point varies from zero to two. Stability analysis shows that one equilibrium point is Hopf point and the other is unstable saddle point when there are two equilibrium points. We also obtain the phase portraits, in which the periodic orbits exist around the Hopf point, and a homoclinic orbit passes through the unstable saddle point.
Energy Technology Data Exchange (ETDEWEB)
Lin Wenhui [College of Science, China Agricultural University, Beijing 100083 (China); Zhao Yapu [State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080 (China)
2007-03-21
The influences of Casimir and van der Waals forces on the nano-electromechanical systems (NEMS) electrostatic torsional varactor are studied. A one degree of freedom, the torsional angle, is adopted, and the bifurcation behaviour of the NEMS torsional varactor is investigated. There are two bifurcation points, one of which is a Hopf bifurcation point and the other is an unstable saddle point. The phase portraits are also drawn, in which periodic orbits are around the Hopf bifurcation point, but the periodic orbit will break into a homoclinic orbit when meeting the unstable saddle point.
Lin, Wen-Hui; Zhao, Ya-Pu
2007-03-01
The influences of Casimir and van der Waals forces on the nano-electromechanical systems (NEMS) electrostatic torsional varactor are studied. A one degree of freedom, the torsional angle, is adopted, and the bifurcation behaviour of the NEMS torsional varactor is investigated. There are two bifurcation points, one of which is a Hopf bifurcation point and the other is an unstable saddle point. The phase portraits are also drawn, in which periodic orbits are around the Hopf bifurcation point, but the periodic orbit will break into a homoclinic orbit when meeting the unstable saddle point.
1986-02-01
163 2.2.4-5 Automatic Brightness/Contrast Compensation System Response Characteristics ’ 63 2.3.1.1-1 Beam Occlusion Phenomena 169 2.3.1.1-2...Automotive Engineering SST saddle-saddle-toroidal TFT thin film transistor TMD tactical modular display TV television ICS uniform chromaticity scale...2.3.1.1.2 Minimum Line Width A beam occlusion phenomenom can occur on a shadow-mask CRT at small line width values, which the literature refers to as bugging
1985-07-18
163 2.2.4-5 Automatic Brightness/Contrast Compensation System Response Characteristics 163 2.3.1.1-1 Beam Occlusion Phenomena 169 2.3.1.1-2...sum of squares SAE Society of Automotive Engineering SST saddle-saddle-toroldal TFT thin film transistor TMD tactical modular display TV television...as tube pitch, video bandwidth, and signal-to-noise ratio must be maximized. 2.3.1.1.2 Minimum Line Width A beam occlusion phenomenom can occur on a
A Comparative Review of Four Photographic Atlases for Microbiology
Directory of Open Access Journals (Sweden)
Deborah Tobiason
2011-09-01
Full Text Available Review of: four photographic atlases for microbiology, including:A Photographic Atlas for the Microbiology Laboratory, Fourth Edition; Michael J. Leboffe and Burton E. Pierce; (2011 . Morton Publishing Company, Englewood, CO. 256 pages. Microbiology: A Photographic Atlas for the Laboratory ; Steven K. Alexander and Dennis Strete; (2001 . Pearson Education, Inc., Upper Saddle River, NJ. 193 pages. Microbiology Perspectives: A Photographic Survey of the Microbial World , Second Edition; George Wistreich; (2007 . Pearson Education, Inc., Upper Saddle River, NJ. 232 pages.and ASM’s MicrobeLibrary Atlas.
Structural Stability of Planar Bimodal Linear Systems
Directory of Open Access Journals (Sweden)
Josep Ferrer
2014-01-01
Full Text Available Structural stability ensures that the qualitative behavior of a system is preserved under small perturbations. We study it for planar bimodal linear dynamical systems, that is, systems consisting of two linear dynamics acting on each side of a given hyperplane and assuming continuity along the separating hyperplane. We describe which one of these systems is structurally stable when (real spiral does not appear and when it does we give necessary and sufficient conditions concerning finite periodic orbits and saddle connections. In particular, we study the finite periodic orbits and the homoclinic orbits in the saddle/spiral case.
Scaled-energy spectroscopy of helium \\|M\\|=1 Rydberg atoms in a static electric field
Kips, Annemieke; Vassen, Wim; Hogervorst, Wim; Dando, Paul A.
1998-10-01
We present scaled-energy spectra on helium Rydberg atoms in a static electric field. \\|M\\|=1 states were studied in excitation from the 2 1S0 metastable state. Spectra were recorded for ɛ=-2.940(4), ɛ=-2.350(4), both below the saddle point, and ɛ=-1.760(4), above the saddle point. Closed-orbit theory was applied to interpret the spectra. A recent extension to closed-orbit theory, incorporating core effects, was used. This significantly improved agreement between experiment and theory.
On intrinsic geometry of surfaces in normed spaces
Burago, Dmitri; Ivanov, Sergei
2010-01-01
We prove three facts about intrinsic geometry of surfaces in a normed (Minkowski) space. When put together, these facts demonstrate a rather intriguing picture. We show that (1) geodesics on saddle surfaces (in a space of any dimension) behave as they are expected to: they have no conjugate points and thus minimize length in their homotopy class; (2) in contrast, every two-dimensional Finsler manifold can be locally embedded as a saddle surface in a 4-dimensional space; and (3) geodesics on c...
Collision of highly charged ion with clusters. Simulation study for electronic systems
Energy Technology Data Exchange (ETDEWEB)
Yabana, Kazuhiro [Niigata Univ. (Japan)
1997-05-01
Collision of highly charged ion with cluster, for example, collision of C{sub 60}-Ar{sup 8+} at E=80 KeV, was simulated by the time-dependence Kohn-Shame equation. The distribution of electron densities and the self-consistent potential were obtained. A part of C{sub 60} potential curve became depressed by the Coulomb force of ion, so that the saddle point was produced on the potential. The behavior of electron transfer on the saddle point was agreed with the classical barrier model. Time-dependent density functional method was explained. (S.Y.)
Petrenko, Serhiy Fedorovich
2013-01-15
A motorized valve has a housing having an inlet and an outlet to be connected to a pipeline, a saddle connected with the housing, a turn plug having a rod, the turn plug cooperating with the saddle, and a drive for turning the valve body and formed as a piezoelectric drive, the piezoelectric drive including a piezoelectric generator of radially directed standing acoustic waves, which is connected with the housing and is connectable with a pulse current source, and a rotor operatively connected with the piezoelectric generator and kinematically connected with the rod of the turn plug so as to turn the turn plug when the rotor is actuated by the piezoelectric generator.
Chaos crisis and bistability of self-pulsing dynamics in a laser diode with phase-conjugate feedback
Energy Technology Data Exchange (ETDEWEB)
Virte, Martin; Karsaklian Dal Bosco, Andreas; Wolfersberger, Delphine; Sciamanna, Marc [Supelec, OPTEL Research Group, Laboratoire Materiaux Optiques, Photonique et Systemes, EA-4423, 2 rue Edouard Belin, F-57070 Metz (France)
2011-10-15
A laser diode subject to a phase-conjugate optical feedback can exhibit rich nonlinear dynamics and chaos. We report here on two bifurcation mechanisms that appear when increasing the amount of light being fed back to the laser. First, we report on a full suppression of chaos from a crisis induced by a saddle-node bifurcation on self-pulsing, so-called external-cavity-mode solutions (ECMs). Second, the feedback-dependent torus and saddle-node bifurcations on ECMs may be responsible for large regions of bistability between ECMs of different and high (beyond gigahertz) frequencies.
meso-Tetrathienylporphyrins: Steady-state emission and structural properties
Indian Academy of Sciences (India)
P Bhyrappa; M Sankar; B Varghese; P Bhavana
2006-09-01
meso-Tetra (2'- and 3'-thienyl)porphyrins and their Zn(II)-complexes were examined by steadystate fluorescence measurements. These molecules exhibit significant bathochromic shift in their emission bands with decreased quantum yields relative to their corresponding meso -tetraphenylporphyrin derivatives. The crystal structure of 5,10,15,20-tetrakis(3'-thienyl)porphinato zinc(II) shows planar and nonplanar stereochemical features of the macrocycle. One of the macrocycle shows nearly planar while the other exhibited predominantly saddle-shaped geometry. The extent of displacement of the -pyrrole carbons in the nonplanar (saddle) conformation is as high as ± 0.422 Å.
Multiple nested basin boundaries in nonlinear driven oscillators☆
Zhang, Yongxiang; Xie, Xiangpeng; Luo, Guanwei
2017-03-01
A special type of basins of attraction for high-period coexisting attractors is investigated, which basin boundaries possess multiple nested structures in a driven oscillator. We analyze the global organization of basins and discuss the mechanism for the appearance of layered structures. The unstable periodic orbits and unstable limit cycle are also detected in the oscillator. The basin organization is governed by the ordering of regular saddles and the regular saddle connections are the interrupted by the unstable limit cycle. Wada basin boundary with different Wada number is discovered. Wada basin boundaries for the hidden and rare attractors are also verified.
Resurgence and dynamics of O(N) and Grassmannian sigma models
2015-01-01
We study the non-perturbative dynamics of the two dimensional O ( N ) and Grassmannian sigma models by using compactification with twisted boundary conditions on ℝ × S 1 $$ \\mathbb{R}\\times {S}^1 $$ , semi-classical techniques and resurgence. While the O ( N ) model has no instantons for N > 3, it has (non-instanton) saddles on ℝ 2 $$ {\\mathbb{R}}^2 $$ , which we call 2d-saddles. On ℝ × S 1 $$ \\mathbb{R}\\times {S}^1 $$ , the resurgent relation between perturbation theory and non-perturbative ...
Fission Barrier for 240Pu in the Quadrupole Constrained Relativistic Mean Field Approach
Institute of Scientific and Technical Information of China (English)
L(U) Hong-Feng; GENG Li-Sheng; MENG Jie
2006-01-01
@@ The fission barrier for 240Pu is investigated beyond the second saddle point in the potential energy surface by the constrained relativistic mean field method with the newly proposed parameter set PK1. The microscopic correction for the centre-of-mass motion is essential to provide the correct potential energy surface. The shell effects that stabilize the nuclei against the fission is also investigated by the Strutinsky method. The shapes for the ground state, fission isomer and saddle-points, etc, are studied in detail.
Preconditioning for Allen–Cahn variational inequalities with non-local constraints
Blank, Luise
2012-06-01
The solution of Allen-Cahn variational inequalities with mass constraints is of interest in many applications. This problem can be solved both in its scalar and vector-valued form as a PDE-constrained optimization problem by means of a primal-dual active set method. At the heart of this method lies the solution of linear systems in saddle point form. In this paper we propose the use of Krylov-subspace solvers and suitable preconditioners for the saddle point systems. Numerical results illustrate the competitiveness of this approach. © 2012 Elsevier Inc.
Multi-phase induced inflation in theories with non-minimal coupling to gravity
Artymowski, Michał; Lalak, Zygmunt; Lewicki, Marek
2017-01-01
In this paper we investigate the induced inflation with two flat regions: one Starobinsky-like plateau in strong coupling regime and one shorter plateau around the saddle point of the Einstein frame potential. This multi-phase inflationary scenario can be used to solve problems of classical cosmology as well as the problem of initial conditions for inflation. The inflation at the saddle-point plateau is consistent with the data and can have arbitrarily low scale. The results can be useful in the context of the Higgs-Axion relaxation and in a certain limit they are equivalent to the α-attractors.
Chaotic dynamics and basin erosion in nanomagnets subject to time-harmonic magnetic fields
Energy Technology Data Exchange (ETDEWEB)
D' Aquino, M., E-mail: daquino@uniparthenope.it [Engineering Department, University of Naples “Parthenope”, 80143 Naples (Italy); Quercia, A.; Serpico, C. [DIETI, University of Naples Federico II, 80125 Naples (Italy); Bertotti, G. [Istituto Nazionale di Ricerca Metrologica, 10135 Torino (Italy); Mayergoyz, I.D. [ECE Department and UMIACS, University of Maryland, College Park, MD 20742 (United States); Perna, S. [DIETI, University of Naples Federico II, 80125 Naples (Italy); Ansalone, P. [Istituto Nazionale di Ricerca Metrologica, 10135 Torino (Italy)
2016-04-01
Magnetization dynamics in uniformly magnetized particles subject to time-harmonic (AC) external fields is considered. The study is focused on the behavior of the AC-driven dynamics close to saddle equilibria. It happens that such dynamics has chaotic nature at moderately low power level, due to the heteroclinic tangle phenomenon which is produced by the combined effect of AC-excitations and saddle type dynamics. By using analytical theory for the threshold AC excitation amplitudes necessary to create the heteroclinic tangle together with numerical simulations, we quantify and show how the tangle produces the erosion of the safe basin around the stable equilibria.
Studies on a New Random Packing-Plum Flower Mini Ring%新一代的乱堆填料——梅花扁环
Institute of Scientific and Technical Information of China (English)
费维扬; 孙兰义; 郭庆丰
2002-01-01
The hydrodynamics and mass transfer of Plum Flower Mini Ring (PFMR), Pall Ring and Intalox Saddle were studied in a 600 mm diameter column with air-oxygen-water system over a wide range of liquid loads. It was shown fiom the experiments that PFMR had much lower resistance, larger throughput and higher mass transfer efficiency than Pall Ring and Intalox Saddle. It was clear from the comparison that existing equations could not predict the performance of packings very well at high liquid loads. Therefore, new semi-empirical equations of pressure drop, flooding gas velocity and height of transfer unit (HTU) were proposed based on the experimental data.
Chinese-English Rocketry Dictionary. Volume 1
1977-10-01
tagdiaclanzn Juntong I n cable drum 20dianlan kaiIhuLI Mg V X cable sheath 21dianlen lianJieqi fit i ict a cable cooectcr 22dianlan leio A l cabling diagran...AMi~ elt xf~ mi hyperballistics 05 gaochaoyinsu daodan A, Mi "I it 4fl hypersonic tissule 06 gaochaoyins’j fanwel iif f) hypersonic region 017...06huadong zuojia M 4&5)m sliding saddle; saddle Q7 huadongbi 4 A sllip ratio Q6 hucdongd r11 i’h sliding 9 huadongdui elt 4 sliding pair
Todorova, Teodora; Alexiev, Valentin; Weber, Thomas
2006-01-01
Hydrogen activation on the (100) surface of MoS[2] structures was investigated by means of density functional theory calculations. Linear and quadratic synchronous transit methods with a conjugate gradient refinement of the saddle point were used to localize transition states. The calculations include heterolytic and homolytic dissociation of…
Comparative Evaluation of Display Technologies for Collaborative Design Review
2009-04-01
Wickens, & Chudy, 2000), in battlefield displays (Wickens, Thomas, Merlo , & Hah, 1999), and in data visualization (McCormick et al., 1998). Select ing...human performance (3rd ed.). Upper Saddle River, NJ: Prentice Hall. Wickens, C. D., Thomas, L., Merlo , J., & Hah, S. (1999). Immersion and battlefield
Multilayered tori in a system of two coupled logistic maps
DEFF Research Database (Denmark)
Zhusubaliyev, Zhanybai; Mosekilde, Erik
2009-01-01
of two coupled logistic maps through period-doubling or pitchfork bifurcations of the saddle cycle on an ordinary resonance torus. We hereafter present two different scenarios by which a multilayered torus can be destructed. One scenario involves a cascade of period-doubling bifurcations of both...
Ankelluksation uden samtidig fraktur af knoglerne
DEFF Research Database (Denmark)
Qayyum, Faiza; Qayyum, Abbas Ali; Sahlstrüm, Sven Arne
2014-01-01
The ankle is a unique modified saddle joint that, together with the subtalar joint, provides range of motion in several physical planes while maintaining stability. The ankle complex functions as a pivoting structure positioned to bear the entire weight of the body which leaves it vulnerable to i...
Institute of Scientific and Technical Information of China (English)
王彩玲; 刘庆怀; 李忠范
2008-01-01
In this paper, we introduce generalized essentially pseudoconvex func-tion and generalized essentially quasiconvex function, and give sufficient optimality conditions of the nonsmooth generalized convex multi-objective programming and its saddle point theorem about cone efficient solution.We set up Mond-Weir type duality and Craven type duality for nonsmooth multiobjective programming with generalized essentially convex functions, and prove them.
Characterization of static bifurcations for n-dimensional flows in the frequency domain
Institute of Scientific and Technical Information of China (English)
Li ZENG; Yi ZHAO
2006-01-01
In this paper n-dimensional flows (described by continuous-time system) with static bifurcations are considered with the aim of classification of different elementary bifurcations using the frequency domain formalism. Based on frequency domain approach, we prove some criterions for the saddle-node bifurcation, transcritical bifurcation and pitchfork bifurcation, and give an example to illustrate the efficiency of the result obtained.
Relating surface pressure to Lagrangian wake topology around a circular cylinder in cross flow
Rockwood, Matthew; Green, Melissa
2016-11-01
The tracks of Lagrangian saddles, identified as non-parallel intersections of positive and negative-time finite-time Lyapunov exponent (FTLE) ridges, have been shown to indicate the timing of von Karman vortex shedding in the wake of bluff bodies. The saddles are difficult to track in real-time, however, since future flow field data is needed for the computation of the FTLE fields. In order to detect the topological changes without direct access to the FTLE, the saddle dynamics are correlated to measurable surface quantities on a circular cylinder in cross flow. The Lagrangian saddle found upstream of a forming and subsequently shedding vortex has been shown to accelerate away from the cylinder surface as the vortex sheds. In previous numerical results at Re = 150 , this acceleration coincides with the peak in lift force over the cylinder, and also with a minimum in the static pressure at a location slightly upstream of the mean separation location. In the current work, this result is compared with experimental data at Re = O (10 , 000) . Successful validation would provide a strategy for locating sensitive regions on the cylinder surface where vortex shedding could be detected using simple pressure transducers. This work was supported by the Air Force Office of Scientific Research under AFOSR Award No. FA9550-14-1-0210.
Numerical Simulation of Active Control on Tip Leakage Flow in Axial Turbine
Institute of Scientific and Technical Information of China (English)
Li Wei; Qiao Weiyang; Xu Kaifu; Luo Hualing
2009-01-01
e efficiency by 0.35% with loose tip clearance, and by 0.3% with tight tip clearance. The number of saddle points is equal to that of nodes near the injection hole, which satisfies the singularity point distribution law.
Cyber Infrastructure Protection
2011-05-01
hundreds of ways. As M. Fishbein and I. Azjen write, “[A] defi- nition of attitude appears to be a minimal prerequisite for the development of valid...the Internet, Upper Saddle River, NJ: Pearson Education Inc., 2009, pp. 408-416. 14. M. Fishbein and I. Azjen, Belief, Attitude, Intention and Be
Institute of Scientific and Technical Information of China (English)
卿恒健
2016-01-01
What is china dream? Different people may have different opinions. But there is no doubt everyone to the understanding of the Chinese dream is good. every Chinese yearning for a better life with this kind of good , and hope for a wealthy and prosperous China is saddled with everyone, this dream is a dream that every Chinese people, and is also the China dream.
Aerodynamics of cyclist posture, bicycle and helmet characteristics in time trial stage.
Chabroux, Vincent; Barelle, Caroline; Favier, Daniel
2012-07-01
The present work is focused on the aerodynamic study of different parameters, including both the posture of a cyclist's upper limbs and the saddle position, in time trial (TT) stages. The aerodynamic influence of a TT helmet large visor is also quantified as a function of the helmet inclination. Experiments conducted in a wind tunnel on nine professional cyclists provided drag force and frontal area measurements to determine the drag force coefficient. Data statistical analysis clearly shows that the hands positioning on shifters and the elbows joined together are significantly reducing the cyclist drag force. Concerning the saddle position, the drag force is shown to be significantly increased (about 3%) when the saddle is raised. The usual helmet inclination appears to be the inclination value minimizing the drag force. Moreover, the addition of a large visor on the helmet is shown to provide a drag coefficient reduction as a function of the helmet inclination. Present results indicate that variations in the TT cyclist posture, the saddle position and the helmet visor can produce a significant gain in time (up to 2.2%) during stages.
Walch, Stephen P.; Rohlfing, Celeste Mcmichael
1989-01-01
The results of CASSCF multireference contracted CI calculations with large ANO basis sets are presented for the exchange region of the HO2 potential-energy surface. The saddle point for H atom exchange is about 13 kcal/mol below the energy of H + O2; therefore, this region of the surface should be accessible during H + O2 recombination and methathesis reactions.
Fission fragment angular distribution in heavy-ion-induced fission with anomalous behavior
Soheyli, S.; Feizi, B.
2014-08-01
Fission fragment angular distribution in heavy-ion-induced fission reactions is of particular importance. Transition state theory is provided to determine the angular distribution of fission fragments which includes standard saddle-point statistical and standard scission-point statistical models. The standard saddle-point statistical model was not able to reproduce the experimental fission fragment angular anisotropies for several heavy-ion-induced fission systems. In contrast to the standard saddle-point model, the standard scission-point statistical model was fairly successful in the prediction of angular anisotropy in heavy-ion-induced fission reaction systems with an anomalous behavior in angular anisotropy of fission fragments, but this model is not widely used as the standard saddle-point statistical model. In this research, a generalized model is introduced for the prediction of fission fragments angular anisotropy in the heavy-ion-induced fission reaction systems having an anomalous behavior. For this purpose, we study the N14,O16,F19+Th232;O16,F19+U238;Mg24,Si28,S32+Pb208;S32+Au197; and O16+Cm248 reaction systems. Finally, it is shown that the presented model is much more successful than previous models.
Unidirectional light emission from low-index polymer microlasers
Energy Technology Data Exchange (ETDEWEB)
Schermer, M.; Wiersig, J., E-mail: jan.wiersig@ovgu.de [Institut für Theoretische Physik, Otto-von-Guericke-Universität Magdeburg, Postfach 4120, D-39016 Magdeburg (Germany); Bittner, S.; Singh, G.; Lebental, M., E-mail: lebental@lpqm.ens-cachan.fr [Laboratoire de Photonique Quantique et Moléculaire, CNRS UMR 8537, Institut d' Alembert FR 3242, École Normale Supérieure de Cachan, 61 Avenue du Président Wilson, F-94235 Cachan (France); Ulysse, C. [Laboratoire de Photonique et Nanostructures, CNRS UPR20, Route de Nozay, F-91460 Marcoussis (France)
2015-03-09
We report on experiments with deformed polymer microlasers that have a low refractive index and exhibit unidirectional light emission. We demonstrate that the highly directional emission is due to transport of light rays along the unstable manifold of the chaotic saddle in phase space. Experiments, ray-tracing simulations, and mode calculations show very good agreement.
Engineering Structurally Configurable Models with Model Transformation
2008-12-15
the FileReader. We assume that the URLs and document contents are stored in a file, which we consider as a database containing all data to be...Upper Saddle River, NJ, USA, 1981. [37] Ram Ramanathan and Jason Redi . A brief overview of ad hoc networks: challenges and directions. Communications
Malanga, Paul R.; Sweeney, William J.
2008-01-01
The study compared the effects of daily assessment and response cards on average weekly quiz scores in an introduction to applied behavior analysis course. An alternating treatments design (Kazdin 1982, "Single-case research designs." New York: Oxford University Press; Cooper et al. 2007, "Applied behavior analysis." Upper Saddle River:…
Institute of Scientific and Technical Information of China (English)
覃江梅
2008-01-01
@@ (A Philosophy of Music Education: Advancing the Vision) (第3版),[美]贝内特·雷默(Bennett Reimer)著上萨德尔河,新泽西;梅黑尔/普伦蒂斯-霍尔出版社(Upper Saddle River,NJ: Merrill/Prentice-Hall)/2003.
A Process to Establish the Common Functions Performed by a Multi-Role Vessel
2010-09-01
ed. 2004, Oxford: Elsevier Butterworth-Heinemann. 13. Grady, J.O., System Requirements Analysis. 1993, Boston: McGraw -Hill. 14. Leedy , P.D. and J.E... Ormrod , Practical Research: Planning and Design. 7th ed. 2001, Upper Saddle River, N.J.: Pearson Prentice Hall. 15. Defence White Paper 2009. 2009
Improving the Signal for U.S. Navy Officer Productivity
2014-12-01
Snell , Dean, & Lepak, 1996). The ability to manage human capital and convert it into useful productivity is a critical skill for executive management...Performance measurement and control systems for implementing strategy. Upper Saddle River, NJ: Prentice-Hall, Inc. Youndt, S. A., Snell , A. S., Dean, J. W
Kuijper, Arjan; Florack, L.M.J.; Viergever, M.A.
2002-01-01
We investigate the deep structure of a scale space image. We concentrate on scale space critical points - points with vanishing gradient with respect to both spatial and scale direction. We show that these points are always saddle points. They turn out to be extremely useful, since the iso-intensity
Regularized semiclassical limits: Linear flows with infinite Lyapunov exponents
Athanassoulis, Agissilaos
2016-08-30
Semiclassical asymptotics for Schrödinger equations with non-smooth potentials give rise to ill-posed formal semiclassical limits. These problems have attracted a lot of attention in the last few years, as a proxy for the treatment of eigenvalue crossings, i.e. general systems. It has recently been shown that the semiclassical limit for conical singularities is in fact well-posed, as long as the Wigner measure (WM) stays away from singular saddle points. In this work we develop a family of refined semiclassical estimates, and use them to derive regularized transport equations for saddle points with infinite Lyapunov exponents, extending the aforementioned recent results. In the process we answer a related question posed by P.L. Lions and T. Paul in 1993. If we consider more singular potentials, our rigorous estimates break down. To investigate whether conical saddle points, such as -|x|, admit a regularized transport asymptotic approximation, we employ a numerical solver based on posteriori error control. Thus rigorous upper bounds for the asymptotic error in concrete problems are generated. In particular, specific phenomena which render invalid any regularized transport for -|x| are identified and quantified. In that sense our rigorous results are sharp. Finally, we use our findings to formulate a precise conjecture for the condition under which conical saddle points admit a regularized transport solution for the WM. © 2016 International Press.
Dadáková, Eva; Pelikánová, Tamara; Kalač, Pavel
2012-03-01
The concentration of putrescine (PUT), spermidine (SPD) and spermine (SPM) was determined in chilled meat and kidneys of 18 rabbits and in liver of 12 animals 24h after slaughter. Very low PUT concentrations were detected only in kidneys. Mean SPD levels were 2.2, 2.2, 61.7 and 32.7mgkg(-1) in saddle, leg, liver and kidneys, respectively. The respective SPM concentrations were 14.7, 8.0, 115 and 88.4mgkg(-1). SPD and SPM losses of about one third of the initial levels were apparent in saddles stored at -18°C for 8months. Losses of both polyamines of about 15-20% of the initial concentrations were found in saddles stored aerobically at +2°C for up to 9days. Stewing of saddles caused significant SPD and SPM losses of about 20-25%, while upon roasting and pan-roasting without oil a decrease of about 50% of the initial concentration was observed.
How to grasp the public? Governmental communication in the Netherlands
Wessel, van M.G.J.
2008-01-01
The Dutch government, like many other governments of advanced democracies, finds itself confronted with political disaffection. Recent cabinets have searched for ways to reconnect with citizens. The main argument made in the article is that these efforts are saddled with constructions of the public,
The biomechanical interaction between horse and rider
Cocq, de P.
2012-01-01
The forces exerted by a rider on a horse have a direct influence on the mechanical load experienced by the horse and consequently on its motion pattern. The aim of this thesis is to explore the biomechanical interaction between rider, saddle and horse in order to get insight in the loading of the ho
2005-03-01
Wright-Patterson AFB OH, March 2004. AFIT/GE/ENG/04-20. 7. Papoulis, Athanasios and S. Unnikrishna Pillai . Probability, Random Variables, and...Upper Saddle River, New Jersey 07458, 2001. 129 13. Swackhammer, Patrick J. Design and Simulation of a Multiple Access Trans- form Domain Communication
An analysis of the intermediate field theory of $T^4$ tensor model
Nguyen, Viet Anh; Eynard, Bertrand
2014-01-01
In this paper we analyze the multi-matrix model arising from the intermediate field representation of the tensor model with all quartic melonic interactions. We derive the saddle point equation and the Schwinger-Dyson constraints. We then use them to describe the leading and next-to-leading eigenvalues distribution of the matrices.
Effective cauda equina decompression in two siblings with Charcot-Marie-Tooth disease type 1B
van Doormaal, Tristan P C; van Ruissen, Fred; Miller, Kai J; Hoogendijk, Jessica E
2016-01-01
Two siblings with Charcot-Marie-Tooth (CMT) 1B due to a c.517G>C (p.Gly173Arg) mutation in the MPZ gene both developed an acute cauda syndrome with unbearable back pain radiating to both legs, progressive muscle weakness of the legs, and saddle hypesthesia with fecal and urinary incontinence. MRI sh
Evaluation of Epoxies to Provide Stress-Free Bonding of Pyroceram Mirrors.
1979-03-01
re-checked for distortion. In this case, the distortion remained at 6-7 fringes with a definite saddling of the surface. The only conclusion which...intorfesorar shown n Fig’ re 53, but the quntitative dOeqrad-lio ni TF could not be, predicted. Figure 55 is a plot of the MT-.’ responsce achie’ved for the
Bifurcations of Invariant Tori and Subharmonic Solutions of Singularly Perturbed System
Institute of Scientific and Technical Information of China (English)
Zhiyong YE; Maoan HAN
2007-01-01
This paper deals with bifurcations of subharmonic solutions and invariant tori generated from limit cycles in the fast dynamics for a nonautonomous singularly perturbed integral manifold, the conditions for the existence of invariant tori are obtained, and the saddle-node bifurcations of subharmonic solutions are studied.
Directory of Open Access Journals (Sweden)
N. Daoudi-Merzagui
2012-01-01
Full Text Available We discuss the existence of subharmonic solutions for nonautonomous second order differential equations with singular nonlinearities. Simple sufficient conditions are provided enable us to obtain infinitely many distinct subharmonic solutions. Our approach is based on a variational method, in particular the saddle point theorem.
Report on assessment of MSSTs for 3 D Mathing Application
DEFF Research Database (Denmark)
Somchaipeng, Kerawit; Sporring, Jon; Kreiborg, Sven;
2004-01-01
cat- egories: changes of positions, changes of relations, and changes of connections. The stability comparison between Extrema-Based MSSTs and Saddle-Based MSSTs is also briefly presented. We point out the equivalence between MSSTs and Multi-Scale Singularity Strings (MSSSs) and propose two sets...
Dynkin game under ambiguity in continuous time
Wu, Helin
2011-01-01
In this paper, we want to investigate some kind of Dynkin's game under ambiguity which is represented by Backward Stochastic Differential Equation (shortly BSDE) with standard generator function g(t, y, z). Under regular assumptions, a pair of saddle point can be obtained and the existence of the value function follows. The constrained case is also treated in this paper.
Institute of Scientific and Technical Information of China (English)
1996-01-01
A number of relics were unearthed when Chinese archaeologists discovered a group of graves in Liaoning Province in April, 1976. Dating back to the Spring and Autumn Period and the Warring States Period, the tombs contained many bronze ornaments for saddles that featured such animals as frogs, snakes, tigers and rabbits.
46 CFR 54.10-15 - Pneumatic test (modifies UG-100).
2010-10-01
... first opportunity following the pneumatic test. The tank supports and saddles, connecting piping, and... 46 Shipping 2 2010-10-01 2010-10-01 false Pneumatic test (modifies UG-100). 54.10-15 Section 54.10... VESSELS Inspection, Reports, and Stamping § 54.10-15 Pneumatic test (modifies UG-100). (a)...
Stride-related rein tension patterns in walk and trot in the ridden horse
Egenvall, Agneta; Roepstorff, Lars; Eisersiö, Marie; Rhodin, Marie; van Weeren, René
2015-01-01
BACKGROUND: The use of tack (equipment such as saddles and reins) and especially of bits because of rein tension resulting in pressure in the mouth is questioned because of welfare concerns. We hypothesised that rein tension patterns in walk and trot reflect general gait kinematics, but are also det
Energy Technology Data Exchange (ETDEWEB)
Sida, J.L
2003-07-01
This document gathers a series of 6 lessons dedicated to students in the first year of their thesis (DEA) in fields and particles physics: 1) the extent of nuclear physics, 2) the nucleus as a cluster of interacting fermions, 3) models and deformation, 4) nuclei and rotation, 5) isospin and exotic nuclei, and 6) fission reactions from the saddle point to the scission point.
On the potential energy landscape of supercooled liquids and glasses
DEFF Research Database (Denmark)
Rodney, D.; Schrøder, Thomas
2011-01-01
The activation-relaxation technique (ART), a saddle-point search method, is applied to determine the potential energy landscape around supercooled and glassy configurations of a three-dimensional binary Lennard-Jones system. We show a strong relation between the distribution of activation energie...
Saarni, Lea; Nygrd, Clas-H kan; Rimpel, Arja; Nummi, Tapio; Kaukiainen, Anneli
2007-01-01
Background: School workstations are often inappropriate in not offering an optimal sitting posture. The aim of this study was to investigate the effects of individually adjustable saddle-type chairs with wheels and desks with comfort curve and arm support on schoolchildren's working postures compared to conventional workstations. Methods:…
Limitations for a Successful Army Leader Development Strategy
2013-05-23
concepts that provide cohesion and focus. Second, 9James Brian Quinn, "Strategies for Change," in Readings in the Strategy Process, ed. Henry Mintzberg ...by Henry Mintzberg and James Brian Quinn, 3-10. Upper Saddle River, N.J.: Prentice Hall, 1998. Schifferle, Peter J. America’s School for War: Fort
Wigner's dynamical transition state theory in phase space : classical and quantum
Waalkens, Holger; Schubert, Roman; Wiggins, Stephen
2008-01-01
We develop Wigner's approach to a dynamical transition state theory in phase space in both the classical and quantum mechanical settings. The key to our development is the construction of a normal form for describing the dynamics in the neighbourhood of a specific type of saddle point that governs t
Hanford Reach - Weed Control Support Within Wildfire Damaged Area
US Fish and Wildlife Service, Department of the Interior — The Saddle Lakes Fire was a lightning caused fire that started on June 28, 2015. This fire burned 14,357 acres total of shrub-steppe, riparian and wetland habitats...
On the behavior of hyperbolic neutral points in two-dimensional ideal magnetohydrodynamics.
Cordoba, D; Marliani, C
1999-03-16
We study ideal incompressible magnetohydrodynamics in two dimensions. We obtain an exponential estimate on the closing of the angle at hyperbolic saddle points of the magnetic stream function under the assumption that the velocity remains bounded. The analytic results are supported by numerical simulations. These results give evidence against a standard scenario for singularity formation for these equations.
2010-06-01
and the characteristic length is 44.45 mm. Finally, the convection coefficient is calculated to be 298 W/m2*K. Incropera and Dewitt note that...Advanced Strength and Applied Elasticity (4th ed.). Upper Saddle, NJ: Prentice Hall PTR, 2003. [11] F. P. Incropera and D. P. DeWitt
Cheshire Cat resurgence, Self-resurgence and Quasi-Exact Solvable Systems
Kozçaz, Can; Tanizaki, Yuya; Ünsal, Mithat
2016-01-01
We explore a one parameter $\\zeta$-deformation of the quantum-mechanical Sine-Gordon and Double-Well potentials which we call the Double Sine-Gordon (DSG) and the Tilted Double Well (TDW), respectively. In these systems, for positive integer values of $\\zeta$, the lowest $\\zeta$ states turn out to be exactly solvable for DSG -- a feature known as Quasi-Exact-Solvability (QES) -- and solvable to all orders in perturbation theory for TDW. For DSG such states do not show any instanton-like dependence on the coupling constant, although the action has real saddles. On the other hand, although it has no real saddles, the TDW admits all-orders perturbative states that are not normalizable, and hence, requires a non-perturbative energy shift. Both of these puzzles are solved by including complex saddles. We show that the convergence is dictated by the quantization of the hidden topological angle. Further, we argue that the QES systems can be linked to the exact cancellation of real and complex non-perturbative saddle...
2015-03-26
SOFTWARE-DEFINED RADIO WITH FPGA PROCESSING THESIS Presented to the Faculty Department of Electrical and Computer Engineering... process images , implement an encryption algorithm or even to act as a general purpose microprocessor. An FPGA is typically chosen in an application where...and Processing . Masters thesis , Landshut University, November 1999. [15] R. Lyons. Understanding Digital Signal Processing . Upper Saddle River, NJ
Analytical methods for an elliptic singular perturbation problem In a circle
Temme, N.M.
2007-01-01
We consider an elliptic perturbation problem in a circle by using the analytical solution that is given by a Fourier series with coefficients in terms of modified Bessel functions. By using saddle point methods we construct asymptotic approximations with respect to a small parameter. In particular
Analytical methods for an elliptic singular perturbation problem in a circle
Temme, N.M.
2006-01-01
We consider an elliptic perturbation problem in a circle by using the analytical solution that is given by a Fourier series with coefficients in terms of modified Bessel functions. By using saddle point methods we construct asymptotic approximations with respect to a small parameter. In particular w
Large optics inspection, tilting, and washing stand
Ayers, Marion Jay; Ayers, Shannon Lee
2010-08-24
A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.
Scott, J. F.
2015-12-01
Unusual domains with curved walls and failure to satisfy the Landau-Lifshitz-Kittel Law are modeled as folding catastrophes (saddle-node bifurcations). This description of ballistic motion in a viscous medium is based upon early work by Dawber et al 2003 Appl. Phys. Lett. 82 436. It suggests that ferroelectric films can exhibit folds or vortex patterns but not both.
Multi-Scale Singularity Trees: Soft-Linked Scale-Space Hierarchies
DEFF Research Database (Denmark)
Somchaipeng, Kerawit; Sporring, Jon; Kreiborg, Sven
2005-01-01
-space is used to construct image hierarchies called Multi-Scale Singularity Trees (MSSTs). We propose two kinds of mathematical landmarks: extrema and saddles. Unlike all other similar methods proposed hitherto, our method produces soft-linked image hierarchies in the sense that all possible connections...
Thirty Years in the Storm: Leadership at an African-Centered School
Piert, Joyce Hafeeza
2013-01-01
For most Americans, access to a quality education has always been perceived as the fundamental link to upward mobility and increased life chances within our society (Ballantine and Hammack in "The sociology of education: a systematic analysis." Prentice Hall, Upper Saddle River, 2011; Brown et al. 2010; Holyfield 2002). This perception…
Effect of a Variable Contact Load on Fretting Fatigue Behavior of Ti-6Al-4V
2004-03-01
were calculated from finite element output [16]. 2.3.5.2. Principal Plane Stresses. A summary of the principal stresses as explained by Hibbeler ...Aerospace Research and Development, Advisory Report 8, 1967. 11 Hibbeler , R. C., Mechanics of Materials. Upper Saddle River N.J., Prentice Hall, pp
The effect of rising and sitting trot on back movements and head-neck position of the horse
Cocq, de P.; Prinsen, H.; Springer, N.C.N.; Weeren, van P.R.; Schreuder, M.; Muller, M.; Leeuwen, van J.L.
2009-01-01
Reason for performing study: During trot, the rider call either rise from the saddle during every stride or remain seated. Rising trot is used frequently because it is widely assumed that it decreases the loading of the equine back. This has, however, not been demonstrated in an objective study. Obj
Nonlinear dynamics of a vectored thrust aircraft
DEFF Research Database (Denmark)
Sørensen, C.B; Mosekilde, Erik
1996-01-01
With realistic relations for the aerodynamic coefficients, numerical simulations are applied to study the longitudional dynamics of a thrust vectored aircraft. As function of the thrust magnitude and the thrust vectoring angle the equilibrium state exhibits two saddle-node bifurcations and three ...
A study on the design of hexapole in an 18-GHz ECR ion source for heavy ion accelerators
Energy Technology Data Exchange (ETDEWEB)
Zhang, Zhan; Wei, Shaoqing; Lee, Sang Jin [Uiduk University, Gyeongju (Korea, Republic of); Choi, Suk Jin [Rare Isotope Science Project, Institute for Basic Science, Daejeon (Korea, Republic of)
2016-06-15
High charge state electron cyclotron resonance (ECR) ion source is important on the performance of heavy ion accelerators. In this paper, a low temperature superconductor (LTS) was used to make a hexapole coil for an 18-GHz ECR ion source. Several hexapole structures, including racetrack, graded racetrack, and saddle were implemented and analyzed for the hexapole-in-solenoid ECR ion source system. Under the appropriate radial confinement field, the smaller outer radius of hexapole can be better for the solenoid design. Saddle hexapole was selected by comparing the wire length, maximum outer radius of the hexapole, the Lorentz force at the end part of the hexapole and the maximum magnetic field in the coil. Based on saddle hexapole, a new design for hexapoles, the snake hexapole, was developed in this paper. By comparative analysis of the Lorentz force at the end part of the saddle and snake hexapoles, the snake hexapole is much better in the ECR ion source system. The suggested design for the ECR ion source with the snake hexapole is presented in this paper.
THE EXISTENCE OF PERIODIC SOLUTIONS TO SECOND ORDER SELF-ADJOINT DIFFERENCE EQUATIONS
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
In this paper, we consider the existence of periodic solutions to a class of second order self-adjoint difference equations. By the least action principle and saddle point theorem in the critical point theory, some new results are obtained. As an application, we also give two examples to demonstrate our main results.
2014-09-18
IEEE, Bogota , Colombia, 2011. [10] Bertsekas, Dimitri P. “Nondifferentiable optimization via approximation”. Mathematical Programming Studies, 3:1...and Differnetial Forms. Prentice-Hall, Inc., Upper Saddle River , NJ, 1999. [40] Isaacson, Douglas and J.E. Robinson III. “A knowledge-based conflict
2011-09-01
Varun Lalchandani, Prasanna Sukumar, and Alejandro Talavera at OPNET in Bethesda, Maryland. They provided exceptional support, debugging the network...Communication –9th Edition. Upper Saddle River: Pearson Prentice-Hall Publishing, 2011. [39] Meeting at OPNET Bethesda April 2011: Alejandro Talavera ...Prasanna Sukumar OPNET Bethesda, Maryland 11. Varun Lalchandani OPNET Bethesda, Maryland 90 12. Alejandro Talavera OPNET Bethesda, Maryland
Hegeman, J.B.J.; Luzginova, N.V.; Jong, M.; Groeneveld, H.D.; Borsboom, A.; Stuivinga, M.E.C.; Laan, J.G. van der
2011-01-01
The mechanical properties of two explosively formed saddle shaped 60 mm thick plates of 316L(N)-IG steel with and without an electron beam weld have been investigated. Two different conditions have been characterized: (1) Reference condition and (2) ITER relevant condition. The reference material ex
Houston, Melissa; Goggins, Patrick
2008-01-01
It used to be much easier to get paid by the San Diego Unified School District (SDUSD). A lot easier, that is, if you didn't work there. Saddled with an antiquated computer system and manual, repetitive data entry of time cards, officials at California's second-largest school district discovered the payroll department was mistakenly issuing $1…
Crises in a driven Josephson junction studied by cell mapping
DEFF Research Database (Denmark)
Sørensen, Mads Peter; Davidson, A.; Pedersen, Niels Falsig;
1988-01-01
We use the method of cell-to-cell mapping to locate attractors, basins, and saddle nodes in the phase plane of a driven Josephson junction. The cell-mapping method is discussed in some detail, emphasizing its ability to provide a global view of the phase plane. Our computations confirm the existe...
Queering Curriculum: "Truth or Dare", Secret Nude Sketches, and Closeted Video Recordings
Bey, Sharif; Washington, G. E.
2013-01-01
In this article, two art teacher trainers explore the possibility of saddling critical pedagogy with queer theory in order to question the art curriculum's potential for critiquing personal relationships. As a preadolescent boy, one author initiated his own sex education curriculum with his middle school peers by creating "secret nude…
Fission barrier heights in the A ∼ 200 mass region
Indian Academy of Sciences (India)
K Mahata
2015-08-01
Statistical model analysis is carried out for - and -induced fission reactions using a consistent description for fission barrier and level density in A ∼ 200 mass region. A continuous damping of shell correction with excitation energy is considered. Extracted fission barriers agree well with the recent microscopic–macroscopic model. The shell corrections at the saddle point were found to be insignificant.
Advanced Methods for Passive Acoustic Detection, Classification, and Localization of Marine Mammals
2013-09-30
vocalizations, including minke (Balaenoptera acutorostrata), blue (B. musculus), and humpback ( Megaptera novaeangliae ) whales. Odontocete clicks. The...ASSP Magazine: 4-16. Rabiner, L.R., and B.H. Juang. (1993). Fundamentals of Speech Recognition. Prentice Hall: Upper Saddle River , New Jersey
Asymmetry in pulse-coupled oscillators with delay.
Zeitler, M.; Daffertshofer, A.; Gielen, C.C.A.M.
2009-01-01
We studied the dynamics of synchronization in asymmetrically coupled neural oscillators with time delay. Stability analysis revealed that symmetric excitatory coupling results in synchrony at multiple phase relations. Asymmetry yields two saddle-node bifurcations of the stable states when coupling i
Infanticide by a solitary koinobiont ichneumonid ectoparasitoid of spiders
Takasuka, Keizo; Matsumoto, Rikio
2011-06-01
When encountering an already parasitized host, a parasitoid's optimal choices (superparasitism, host rejection, host feeding or infanticide) seem to depend on the individual species' life history, because the same choice may have different fitness consequences. We demonstrate infanticide under laboratory conditions by a polysphinctine, Zatypota albicoxa, which is a solitary koinobiont ectoparasitoid of spiders. The female always removed any previously attached egg or larva from the body of the host spider, Parasteatoda tepidariorum, with a rubbing behaviour. She rubbed her ovipositor back and forth toward the undersurface of the attached egg or of the saddle under the attached larva to pry it off and laid an egg after removal. When removing a larva, the infanticidal female engaged exclusively in unfastening the `saddle' which fastens the larva to the body of the spider. All larvae were removed with the `saddle' attached to the ventral surface of the body. The female invested more time to remove the medium second and the large penultimate instar larvae than to remove eggs and first instar larvae because of the labour involved in unfastening the saddle. Oviposition with infanticide of the medium second and the penultimate instar larvae imposed more time upon the female than that on an unparasitized host. Removal of any previous occupant in spite of the associated labour costs suggests that infanticide will always be adaptive, no matter the time costs to Z. albicoxa, because so much is invested in attacking the host and because the parasitoid cannot detect whether the spider is already parasitized until she achieves subjugation.
2011-09-30
the Southern California Bight: bottlenose dolphins ( Tursiops truncatus ), short- and long-beaked common dolphins (Delphinus delphis and D. capensis...architectures used in the PAM boards of each instrument. 8 REFERENCES Haykin, S. 2002. Adaptive Filter Theory. Prentice-Hall, Upper Saddle River
Network search method in the design of extreme ultraviolet lithographic objectives
Marinescu, O.; Bociort, F.
2007-01-01
The merit function space of mirror system for extreme ultraviolet (EUV) lithography is studied. Local minima situated in the multidimensional optical merit function space are connected via links that contain saddle points and form a network. We present networks for EUV lithographic objective designs
Expeditions and other exploration
Steenis, van C.G.G.J.
1983-01-01
The Botanical Survey of India continued to make collections during 1982, with the following results: Andaman & Nicobar Is.: Shola Bag, Mt Harriet, Jirkathang, Poona Nallah, Saddle peak, Diglipur, Rutland I. & Little I., 2875 specimens. Arunachal Pradesh: Various areas of Kameng Distr., Subansiri Dis
A Probabilistic Approach to Second Order Variational Inequalities with Bilateral Constraints
Indian Academy of Sciences (India)
Mrinal K Ghosh; K S Mallikarjuna Rao
2003-11-01
We study a class of second order variational inequalities with bilateral constraints. Under certain conditions we show the existence of a unique viscosity solution of these variational inequalities and give a stochastic representation to this solution. As an application, we study a stochastic game with stopping times and show the existence of a saddle point equilibrium.
1990-06-01
for use in training research, tempered by our perception of the current political climate , we recommended that no immediate action be taken by the...RUN CHECKPOINTS Number Description Location 1 TRAIL CUT THROUGH TREELINE PK268452 2 SADDLE 261454 3 FINGER 240470 4 RIDGE LINE 251456 5 RIDGE LINE
2012-07-01
Gonzalez , Rafael , Richard Woods, Digital Image Processing . Upper Saddle River, NJ: Prentice Hall, 2002 \\ 2214 ...dimensional image with the axes image is then post processed to ach class nodes ction ltrasonic and profiling data sor r sensor used here...detection. The focus is on using low cost non- imaging sensors for applications such as border crossings where issues of rapid deployment and
Effective Lagrangian of C PN -1 models in the large N limit
Rossi, Paolo
2016-08-01
The effective low energy Lagrangian of C PN -1 models in d <4 dimensions can be constructed in the large N limit by solving the saddle point equations in the presence of a constant field strength. The two-dimensional case is explicitly worked out, and possible applications are briefly discussed.
Diffuse Prior Monotonic Likelihood Ratio Test for Evaluation of Fused Image Quality Measures
2011-02-01
Program., vol. 47, pp. 425–439, May 1990. [31] T. Moon and W. C. Stirling , Mathematical Methods and Algorithms for Signal Processing. Upper Saddle...Conf., Big Sky , MT, Mar. 2006. [40] D.-O. Kim and R.-H. Park, “New image quality metric using the Harris response,” IEEE Signal Process. Lett., vol
Topological fluid mechanics of the formation of the Kármán-vortex street
DEFF Research Database (Denmark)
Heil, Matthias; Rosso, Jordan; Hazel, Andrew L.;
2017-01-01
consider to be feature points for vortices. The basic vortex creation mechanism is shown to be a topological cusp bifurcation in the vorticity field, where a saddle and an extremum of the vorticity are created simultaneously. We demonstrate that vortices are first created approximately 100 diameters...
78 FR 766 - Notice of Determinations Regarding Eligibility To Apply for Worker Adjustment Assistance
2013-01-04
.... 82,132B Lattice Semiconductor Hillsboro, OR........ November 2, 2011. Corporation, Finance Department........... November 2, 2011. Corporation, Corporate Marketing Department. 82,135 The Hospital of Central New Britain.... Subject firm Location Impact date 82,171 Pearson Education, Inc., Upper Saddle River, November 21,...
Unidirectional light emission from low-index polymer microlasers
Schermer, M; Singh, G; Ulysse, C; Lebental, M; Wiersig, J
2014-01-01
We report on experiments with deformed polymer microlasers that have a low refractive index and exhibit unidirectional light emission. We demonstrate that the highly directional emission is due to transport of light rays along the unstable manifold of the chaotic saddle in phase space. Experiments, ray-tracing simulations, and mode calculations show very good agreement.
Identification of a Smartphone User via Keystroke Analysis
2014-03-01
too big. Russell and Norvig point out that nearest neighbors’ algorithms are well suited for situations with lower feature counts and robust data sets...en_stat.html. [Accessed 17 December 2013]. [16] S. Russell and P. Norvig , Artificial Intelligence: A Modern Approach. Upper Saddle River, NJ: Pearson
Authentication of Smartphone User Using RSSI Geolocation
2014-03-01
decoding, and learning. Chapter 15 of Russell and Norvig [13] describes the mathematical process to solve the fundamental problems. Once the fundamental...13] S. Russell and P. Norvig , Artificial Intelligence, a modern approach. 3rd ed., M. Hirsch, Ed. Upper Saddle River: Pearson Education, Inc., 2010
Creating Profiles from User Network Behavior
2013-09-01
2005. [25] S. Russell and P. Norvig , Artificial Intelligence: A Modern Approach, 3rd ed. Upper Saddle River, NJ: Prentice Hall Press, 2009. [26] S...Mockapetris, Paul V. 6, 7, 15 Moore, Andrew 5 Moore, Andrew P. 6 Mundie, David 6 Noonan, C. F. 5 Norvig , Peter 21, 22 O’Neil, Cathy 22 Orimo, Emiko 1
2014-01-01
environment and direct their activity towards achieving goals (Russell & Norvig , 2003). In computer-based tutors, learning agents observe and act upon... Norvig , P. (2003). Artificial Intelligence: A Modern Approach (2nd ed.). Upper Saddle River, New Jersey: Prentice Hall, ISBN 0-13-790395-2