International Nuclear Information System (INIS)
Microbial fuel cell (MFC) is an upcoming technology that allows oxidizing organic matter to generate current by microorganism's activity. To render MFCs a cost-effective and energy sustainable technology, low-cost materials can be employed as support for bacteria growth and proliferation. With this purpose in mind, ceramic Berl saddles were opportunely covered by a thin and conductive carbon layer, thus obtaining an innovative low-cost anode material able to efficiently recover the electrons released by bacteria metabolisms. The conductive layer was obtained by using α-D-glucose deposition process within the following steps: impregnation, caramelization, and pyrolysis. In this way, a homogenous coating of polycrystalline graphitic carbon was successfully obtained and characterized by several methods. The carbon-coated Berl saddles were then tested as anode material in a two-compartment MFC prototype, in batch mode and using Saccharomyces cerevisiae as active microorganisms. The MFC performances were evaluated using electrochemical techniques. The carbon-coated Berl saddles showed a maximum power density of 130 mW m−2 (29.6 mA L−1) which is about 2–3 times higher than the values reported in literature by using commercial anode materials. In particular, we have carefully estimated the production and process costs of these carbon-coated Berl saddles used in our MFC prototype, obtaining a value comparable to the commercial carbon felt employed in the same MFC apparatus. All these results confirm that our innovative carbon-coated Berl saddles not only satisfy the electrical requirements, but also favor an optimal bacteria adhesion and can be produced as a low-cost anode for scaling-up MFC. - Highlights: • Berl saddles were opportunely covered by a conductive carbon layer. • New and easy electrode preparation methods offer a low-cost solution for MFC anode. • Power density using coated Berl saddles is comparable to commercial materials. • Coated
Is Berle and Means Really a Myth?
Brian Cheffins and Steven Bank
2009-01-01
Adolf Berle and Gardiner Means famously declared in 1932 that a separation of ownership and control was a hallmark of large U.S. corporations, and their characterization of matters quickly became received wisdom. A series of recent papers has called the Berle-Means orthodoxy into question. This survey of the relevant historical literature acknowledges that the pattern of ownership and control in U.S. public companies is not monolithic. Nevertheless, a separation between ownership and control ...
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
La reconstrucci??n de Berl??n tras la Segunda Guerra Mundial
Mart??nez-Monedero, Miguel
2004-01-01
En la 1?? d??cada del s. XXI Berl??n presume de una nueva expresi??n arquitect??nica que tuvo su momento de partida en la reunificaci??n del a??o 1989. En este art??culo se hace un repaso de c??mo fue el comienzo de la reconstrucci??n de Berl??n y c??mo se establecieron las bases para que, a partir de la reunificaci??n, se produjera la efervescencia constructiva que se ha experimentado en la ciudad. Si la ca??da del muro fue el momento de la reunificaci??n entre las dos Alemanias, conocer el ...
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
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.
La reconstrucci??n de Berl??n, la b??squeda de una nueva identidad
Mart??nez-Monedero, Miguel
2008-01-01
Fue en Berl??n donde se dieron las soluciones m??s parad??jicas y controvertidas, motivadas sin duda por la quir??rgica y traum??tica divisi??n de la ciudad en varios bloques primero, y en dos sectores despu??s, con el levantamiento del muro en los tempranos a??os 60. A esto hemos de a??adir que la recuperaci??n del pasado hist??rico corri?? pareja e indisolublemente unida a la recuperaci??n econ??mica. El espectacular desarrollo econ??mico que alcanz?? el pa??s en los a??os 50, el llamado ??...
Complexified Path Integrals, Exact Saddles, and Supersymmetry.
Behtash, Alireza; Dunne, Gerald V; Schäfer, Thomas; Sulejmanpasic, Tin; Ünsal, Mithat
2016-01-01
In the context of two illustrative examples from supersymmetric quantum mechanics we show that the semiclassical analysis of the path integral requires complexification of the configuration space and action, and the inclusion of complex saddle points, even when the parameters in the action are real. We find new exact complex saddles, and show that without their contribution the semiclassical expansion is in conflict with basic properties such as the positive semidefiniteness of the spectrum, as well as constraints of supersymmetry. Generic saddles are not only complex, but also possibly multivalued and even singular. This is in contrast to instanton solutions, which are real, smooth, and single valued. The multivaluedness of the action can be interpreted as a hidden topological angle, quantized in units of π in supersymmetric theories. The general ideas also apply to nonsupersymmetric theories. PMID:26799010
A 40 años de la construcción del muro de Berlín
Maffeo, Aníbal José
2001-01-01
En este número recordamos el 40° aniversario de la construcción del Muro de Berlín. Este fue un hecho relevante para el sistema internacional, ya que su historia y, sobre todo su fin, trajo consecuencias en el mundo actual.
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....
Phase retrieval and saddle-point optimization
Marchesini, S
2006-01-01
Iterative algorithms with feedback are amongst the most powerful and versatile optimization methods for phase retrieval. Among these, the hybrid input-output algorithm has demonstrated remarkable success in performing giga-element nonlinear optimization, escaping local minima and producing images at resolutions beyond the capabilities of lens-based optical methods. Here the input-output iteration is improved by a lower dimensional subspace saddle-point optimization.
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.
Producció alemanya cinematogràfica ambientada a la caiguda del mur de Berlín (1989)
Petrus Coll, Marina
2015-01-01
El present treball ofereix un revisió i anàlisi de la producció cinematogràfica alemanya ambientada a la caiguda del Mur de Berlín. A través de l'anàlisi formal i audiovisual de cinc pel•lícules es construeix una conclusió i valoració sobre el cinema alemany i la finalitat d'aquestes. El presente trabajo ofrece un revisión y análisis de la producción cinematográfica alemana ambientada en la caída del Muro de Berlín. A través del análisis formal y audiovisual de cinco películas se construye...
Interbau. Exposición internacional de la construcción – Berlín
Directory of Open Access Journals (Sweden)
Cassinello, Fernando
1957-11-01
Full Text Available La Exposición Internacional de la Construcción, organizada por el Gobierno federal alemán en Berlín —Interbau—, ha constituido un verdadero éxito, tanto por la magnitud de sus obras como por la talla de los técnicos concurrentes y perfecta organización del certamen.
Memoria de la Shoah: el caso de Berlín
Directory of Open Access Journals (Sweden)
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.
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.
Saddle nose: Autologous augmentation techniques and their relevant patient satisfaction
Wael Khamis Abdel-Hamid Hussein
2015-01-01
Introduction: The analysis and treatment of saddle nose have always been a surgical challenge. The study describes the three-stage classification of this deformity as well as a treatment algorithm adapted to each case. Materials and methods: A prospective study was carried out on 46 patients with saddle nose. The patients were divided into 3 groups according to the severity of saddling; minimal, moderate and major. The authors describe the treatment protocol adopted for each stage. Resu...
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.
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.
Un puente entre los mundos. El Instituto Ibero-Americano de Berlín
Directory of Open Access Journals (Sweden)
Diana von Römer
2005-10-01
Full Text Available El presente artículo ofrece al lector una visión de conjunto sobre el Instituto Ibero-Americano (IAI en Berlín. En primer lugar, relata la historia del instituto desde que se fundara en 1930, cuando surgió el modelo de tres pilares: información, investigación e intercambio cultural, hasta la actualidad, en la que éste sigue vigente. A continuación se exponen en detalle las tres funciones principales que cumple el instituto: centro de información - el IAI alberga la mayor biblioteca de Europa especializada en las culturas ibero-americanas - con sus diversos fondos y colecciones; centro de investigación, con el apoyo a la investigación a través de becas, publicaciones y coloquios; y finalmente el centro cultural, con actividades de diversa índole en colaboración con otras instituciones y embajadas, favoreciendo así el diálogo entre Alemania e Iberoamérica, el Caribe, España y Portugal.
Getting a grip on the saddle: Chasms or cycles?
Chandrasekaran, D. (Deepa); G.J. Tellis (Gerard)
2011-01-01
textabstractThe "saddle" is a sudden, sustained, and deep drop in sales of a new product, after a period of rapid growth following takeoff, followed by a gradual recovery to the former peak. The authors test for the generalizability of the saddle across products and countries and for three rival exp
The Formual of Generalized Center－Weak Saddle
Institute of Scientific and Technical Information of China (English)
万维明; 迟晓恒
2002-01-01
In his paper,a problem of center-weak focus of a general system of degree n is transformed into a problem of generalized center-weak saddle.It offers:(1) the calculating formula of the saddle values of the former 4 orders in the general system of degree three;(2) some calculating formulae of the saddle values in the general homogeneous system of degree n. The problem of center-focus(saddle)plays an important role in the qualitative theory of ordinary differential equations.However,since the calculations are difficult,the results have not been satisfactory.On the basis of the author's work,Northeast.Math.J.,13(4)(1997),487-494,the paper offers some calculating formulae of the saddle values.
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.
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.
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.
Oscillation of Hot Fissioning Nuclei around a Saddle Point
Institute of Scientific and Technical Information of China (English)
BAO Jing-Dong; L(U) Kun; LIU Ling; JIA Ying
2005-01-01
@@ Three time scales of a fissioning nucleus starting from the ground state to the scission point are defined and calculated by the Monte Carlo method. The result shows that the time of oscillating around the saddle point is longer than both the mean first passage time from the ground state to the saddle point and the time of descent from the saddle to scission points. Thus it is suggested that more neutrons could be emitted from a hot heavy fissioning nucleus during the period of the stretching and contracting of the deformation process.
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}
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.
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.
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.
Resonance wave functions located at the Stark saddle point
International Nuclear Information System (INIS)
The hydrogen atom in crossed static electric and magnetic fields is an important example for a quantum system accessible both in experiments and numerical calculations. Adding external fields to the Coulomb potential of the hydrogen atom opens the possibility for wave functions to be localized far away from the nucleus. In particular, the existence of resonances localized in the vicinity of the Stark saddle point predicted by simple expansions of the potential around the saddle has been unclear for a long time. We calculate quantum mechanically exact wave functions of resonances in spectra of the hydrogen atom in crossed external fields and prove the existence of the long-lived decaying quantum states localized at the Stark saddle point. A spectrum of ground and excited states reproducing the nodal patterns expected from simple quadratic and cubic expansions of the potential in the vicinity of the saddle can be identified.
Clinical and functional outcomes of the saddle prosthesis
Donati, D.; D’Apote, G.; M. Boschi; Cevolani, L.; M.G. Benedetti
2012-01-01
Background The implantation of a saddle prosthesis after resection of a pelvic tumor has been proposed as a simple method of reconstruction that provides good stability and reduces the surgical time, thus limits the onset of intraoperative complications. There are no studies in the literature of patients evaluated using gait analysis after being implanted with a saddle prosthesis. The present study is a retrospective case review aimed at illustrating long-term clinical and functional findings...
New Preconditioners for Nonsymmetric Saddle Point Systems with Singular Block
Qingbing Liu
2013-01-01
We investigate the solution of large linear systems of saddle point type with singular (1,1) block by preconditioned iterative methods and consider two parameterized block triangular preconditioners used with Krylov subspace methods which have the attractive property of improved eigenvalue clustering with increased ill-conditioning of the (1,1) block of the saddle point matrix, including the choice of the parameter. Meanwhile, we analyze the spectral characteristics of two preconditioners and...
Cuesta Barriga, Sara
2013-01-01
El presente trabajo propone una unidad didáctica sobre el Muro de Berlín para demostrar que se puede integrar en el aula de Alemán como Lengua Extranjera en la Educación Secundaria Superior una Landeskunde entendida como "cultura" en su sentido tradicional sin desatender las necesidades comunicativas del alumnado.
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.
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. PMID:27544086
Las fronteras en el muro de Berlín: frente, fronda y solitón
David Casado Neira
2008-01-01
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...
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.
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.
Reconstruction of saddle nose deformity with calvarial bone graft
International Nuclear Information System (INIS)
Objective: To evaluate the efficacy of calvarial bone in the reconstruction of saddle nose deformity. Methods: The cross-sectional study was conducted at the Plastic Surgery Unit of Imam Reza Hospital, Tabriz University of Medical Sciences, Iran, from July 2004 to October 2009. It comprised 19 patients who underwent saddle nose deformity reconstruction with calvarial bone graft. All patients were operated upon under general anaesthesia. They were followed up periodically. Results: The patients followed up for 25 to 61 months for an average period of 39.2+-4.3 months. In 14 (74%) patients the result of the surgical intervention was excellent, while in 5 (26%) it was acceptable. All patients were satisfied and there was not displacement, absorption, distortion or infection of the graft. Conclusion: Calvarial bone graft is a viable option for the reconstruction of saddle nose deformity, especially in severe cases. (author)
Decay of isolated hills and saddles on Si(001)
Kirschbaum, Pierre; Brendel, Lothar; Roos, Kelly R.; Horn-von Hoegen, Michael; Heringdorf, Frank-J. Meyer zu
2016-08-01
We discuss the high temperature decay of isolated hills and saddle points on Si(001). Using in situ dark-field imaging in low energy electron microscopy, we track the movement of individual steps during high temperature annealing. We find different temperature dependent decay rates for the top of the hill compared to a saddle point with low step density that is present in the vicinity of the hill. The decay rate of the hill is always higher than the decay rate at the saddle. The two rates converge with increasing temperature and become equal at temperatures above 1060 °C. We also report an alternating fast and low decay rate for the layer-by-layer decay of the hills. This surprising finding is independent of temperature and is explained by macroscopic strain in the sample.
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.
Complex saddle points in finite-density QCD
Nishimura, Hiromichi; Pangeni, Kamal
2015-01-01
We consider complex saddle points in QCD at finite temperature and density, which are constrained by symmetry under charge and complex conjugations. This approach naturally incorporates color neutrality, and the Polyakov loop and the conjugate loop at the saddle point are real but not identical. Moreover, it can give rise to a complex mass matrix associated with the Polyakov loops, reflecting oscillatory behavior in color-charge densities. This aspect of the phase structure appears to be sensitive to the origin of confinement, as modeled in the effective potential.
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.
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. PMID:22380221
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.
The Pi Graft for Correction of Severe Saddle Nose Deformity.
Zelken, Jonathan; Chang, Chun-Shin; Hsiao, Yen-Chang
2016-08-01
Saddle nose deformity is challenging because there is both aesthetic and functional compromise, and high rates of recurrence have been reported. Autologous costal cartilage is the widely preferred medium for reconstruction, but there may be room for improvement in the configuration of the cartilage struts. The pi graft is stabilized at two points, proximally and distally, distinguishing it from the traditional L-strut. Indications include severe (Types III and IV) saddle nose deformity with collapse of the mid-vault, and recurrence after prior reconstruction. Costal cartilage is harvested and three struts are crafted to make the foundation layer: a dorsal strut, caudal strut, and mid-vault strut. An aesthetic layer is composed of a carefully crafted dorsal graft and tip graft. Three men and 11 women were treated from 2013 to 2015 using this method for severe saddle nose deformity. Aesthetic and functional outcomes were evaluated. Patients were followed up for 12 months (range, 8-14 months). There was no recurrence of deformity or warping of the aesthetic or foundation layers. All patients were guided to anticipate refinement of the tip at 3 months to ease the burden on the skin envelope in stage I, but only five patients (35.7%) opted for it, as the remaining patients were satisfied with their appearance. The pi graft is a composite reconstructive method that is designed to minimize warping and recurrence of the saddle nose deformity. This method was successful in this series, although objective comparisons with traditional methods were not made. PMID:27494591
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.
Stochastic Variance Reduction Methods for Saddle-Point Problems
Balamurugan, P.; Bach, Francis
2016-01-01
We consider convex-concave saddle-point problems where the objective functions may be split in many components, and extend recent stochastic variance reduction methods (such as SVRG or SAGA) to provide the first large-scale linearly convergent algorithms for this class of problems which is common in machine learning. While the algorithmic extension is straightforward, it comes with challenges and opportunities: (a) the convex minimization analysis does not apply and we use the notion of monot...
A la luz de las cúpulas. Restauración del Reichstag de Berlín (1992-1999), Foster & Partners
Trillo de Leyva, Manuel
2010-01-01
Durante el curso académico 2000-2001, los profesores del Aula Taller F realizaron un seminario dedicado a la arquitectura contemporánea de Berlín. Además de las conferencias impartidas se visitaron las obras que habían sido analizadas en el seminario. Este artículo, escrito en marzo de 2001, añade una reflexión final, escrita en marzo del año 2002, consecuencia de esa visita conjunta que, profesores y estudiantes, realizaron al Reigchstag. Con el cambio de milenio, las principales ciudade...
El IEO se adhiere a la Declaración de Berlín sobre acceso abierto al conocimiento científico
Lozano, P.; Mosquera-de-Arancibia, C. (Concha)
2016-01-01
El 24 de junio de 2016, el Instituto Español de Oceanografía oficializó su adhesión a la Berlin Declaration on Open Access to Knowledge in the Sciences and Humanities, hito del movimiento de acceso abierto al conocimiento científico gestionado por la Max Planck Society. Los firmantes de la Declaración de Berlín defienden el uso de internet como medio funcional que sirva de base global al conocimiento científico y la reflexión humana. Los declarantes consideran que la misión de diseminar el co...
Saddle point inflation in string-inspired theory
International Nuclear Information System (INIS)
The observed value of the Higgs mass indicates the possibility that there is no supersymmetry below the Planck scale and that the Higgs can play the role of the inflaton. We examine the general structure of saddle point inflation in string-inspired theory without supersymmetry. We point out that the string scale is fixed to be around the GUT scale ∼1016 GeV in order to realize successful inflation. We find that the inflaton can be naturally identified with the Higgs field
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...
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.
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.
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 $2m≥ p > 2$.
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.
Relative variances of the cadence frequency of cycling under two differential saddle heights.
Chang, Wen-Dien; Fan Chiang, Chin-Yun; Lai, Ping-Tung; Lee, Chia-Lun; Fang, Sz-Ming
2016-01-01
[Purpose] Bicycle saddle height is a critical factor for cycling performance and injury prevention. The present study compared the variance in cadence frequency after exercise fatigue between saddle heights with 25° and 35° knee flexion. [Methods] Two saddle heights, which were determined by setting the pedal at the bottom dead point with 35° and 25° knee flexion, were used for testing. The relative variances of the cadence frequency were calculated at the end of a 5-minute warm-up period and 5 minutes after inducing exercise fatigue. Comparison of the absolute values of the cadence frequency under the two saddle heights revealed a difference in pedaling efficiency. [Results] Five minutes after inducing exercise fatigue, the relative variances of the cadence frequency for the saddle height with 35° knee flexion was higher than that for the saddle height with 25° knee flexion. [Conclusion] The current finding demonstrated that a saddle height with 25° knee flexion is more appropriate for cyclists than a saddle height with 35° knee flexion. PMID:27065522
What is QFT? Resurgent trans-series, Lefschetz thimbles, and new exact saddles
Dunne, Gerald V
2015-01-01
This is an introductory level review of recent applications of resurgent trans-series and Picard-Lefschetz theory to quantum mechanics and quantum field theory. Resurgence connects local perturbative data with global topological structure. In quantum mechanical systems, this program provides a constructive relation between different saddles. For example, in certain cases it has been shown that all information around the instanton saddle is encoded in perturbation theory around the perturbative saddle. In quantum field theory, such as sigma models compactified on a circle, neutral bions provide a semi-classical interpretation of the elusive IR-renormalon, and fractional kink instantons lead to the non-perturbatively induced gap, of order of the strong scale. In the path integral formulation of quantum mechanics, saddles must be found by solving the holomorphic Newton's equation in the inverted (holomorphized) potential. Some saddles are complex, multi-valued, and even singular, but of finite action, and their ...
Complex Saddle Points and Disorder Lines in QCD at finite temperature and density
Nishimura, Hiromichi; Pangeni, Kamal
2014-01-01
The properties and consequences of complex saddle points are explored in phenomenological models of QCD at non-zero temperature and density. Such saddle points are a consequence of the sign problem, and should be considered in both theoretical calculations and lattice simulations. Although saddle points in finite-density QCD are typically in the complex plane, they are constrained by a symmetry that simplifies analysis. We model the effective potential for Polyakov loops using two different potential terms for confinement effects, and consider three different cases for quarks: very heavy quarks, massless quarks without modeling of chiral symmetry breaking effects, and light quarks with both deconfinement and chiral symmetry restoration effects included in a pair of PNJL models. In all cases, we find that a single dominant complex saddle point is required for a consistent description of the model. This saddle point is generally not far from the real axis; the most easily noticed effect is a difference between ...
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 point solutions in Yang-Mills-dilaton theory
Bizón, P
1993-01-01
The coupling of a dilaton to the $SU(2)$-Yang-Mills field leads to interesting non-perturbative static spherically symmetric solutions which are studied by mixed analitical and numerical methods. In the abelian sector of the theory there are finite-energy magnetic and electric monopole solutions which saturate the Bogomol'nyi bound. In the nonabelian sector there exist a countable family of globally regular solutions which are purely magnetic but have zero Yang-Mills magnetic charge. Their discrete spectrum of energies is bounded from above by the energy of the abelian magnetic monopole with unit magnetic charge. The stability analysis demonstrates that the solutions are saddle points of the energy functional with increasing number of unstable modes. The existence and instability of these solutions are "explained" by the Morse-theory argument recently proposed by Sudarsky and Wald.
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.
Measuring the distance from saddle points and driving to locate them over quantum control landscapes
International Nuclear Information System (INIS)
Optimal control of quantum phenomena involves the introduction of a cost functional J to characterize the degree of achieving a physical objective by a chosen shaped electromagnetic field. The cost functional dependence upon the control forms a control landscape. Two theoretically important canonical cases are the landscapes associated with seeking to achieve either a physical observable or a unitary transformation. Upon satisfaction of particular assumptions, both landscapes are analytically known to be trap-free, yet possess saddle points at precise suboptimal J values. The presence of saddles on the landscapes can influence the effort needed to find an optimal field. As a foundation to future algorithm development and analyzes, we define metrics that identify the ‘distance’ from a given saddle based on the sufficient and necessary conditions for the existence of the saddles. Algorithms are introduced utilizing the metrics to find a control such that the dynamics arrive at a targeted saddle. The saddle distance metric and saddle-seeking methodology is tested numerically in several model systems. (paper)
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.
Medical image of the week: saddle pulmonary embolism
Directory of Open Access Journals (Sweden)
Jaffer F
2016-05-01
Full Text Available No abstract available. Article truncated at 150 words. A 66-year-old woman with recent history of left knee surgery and L2-L5 spinal fusion within the past month presented to the Emergency Department (ED with pleuritic chest pain and shortness of breath for three days. On admission, reported crushing diffuse substernal chest pain worsened to 10/10 on the pain scale on the day of presentation. In the ED, physical examination was remarkable for tachycardia, tachypnea, diaphoresis and hypotension. Initial electrocardiogram was significant for sinus tachycardia with S1Q3T3 pattern. thoracic computed tomography angiogram (CTA showed saddle pulmonary embolus (PE with extension into segmental vasculature, right greater than left (Figure 1. A bedside echocardiogram demonstrated diastolic and systolic bowing of the intraventricular septum into the left ventricle. An emergent trans-thoracic echocardiogram confirmed flattened septum consistent with right ventricle pressure overload with right ventricular systolic pressure of 55 mmHg + central venous pressure (CVP and reduced left ventricular ejection fraction of 38%. Her ...
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...
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.
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.
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...
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
to the path. The method is applied to Al adatom diffusion on the Al(100) surface to find the ridge between 2-, 3- and 4-atom concerted displacements and hop mechanisms. A correction to the harmonic approximation of transition state theory was estimated by direct evaluation of the configuration integral along......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 harmonic...... approximation to transition state theory, in particular to verify that second order saddle points—maxima along the ridge—are high enough compared to the first order saddle points. New minima along the ridge can also be identified during the path optimisation, thereby revealing additional transition mechanisms...
Generating saddle points in the merit function landscape of optical systems
Bociort, Florian; van Turnhout, Maarten
2005-09-01
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 complexity. We have recently shown that saddle points known in mathematics as Morse index 1 saddle points can be useful for global optical system optimization. In this work we show that by inserting a thin meniscus lens (or two mirror surfaces) into an optical design with N surfaces that is a local minimum, we obtain a system with N+2 surfaces that is a Morse index 1 saddle point. A simple method to compute the required meniscus curvatures will be discussed. Then, letting the optimization roll down on both sides of the saddle leads to two different local minima. Often, one of them has interesting special properties.
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.
Optimal path of diffusion over the saddle point and fusion of massive nuclei
Wang, Chun-Yang; Jia, Ying; Bao, Jing-Dong
2008-01-01
Diffusion of a particle passing over the saddle point of a two-dimensional quadratic potential is studied via a set of coupled Langevin equations and the expression for the passing probability is obtained exactly. The passing probability is found to be strongly influenced by the off-diagonal components of inertia and friction tensors. If the system undergoes the optimal path to pass over the saddle point by taking an appropriate direction of initial velocity into account, which departs from t...
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.
Imágenes de una revolución: la caída del muro de Berlín en los medios de comunicación
Ruiz de Larramendi Herranz, María
2015-01-01
El presente trabajo de fin de grado trata del tratamiento que los medios de comunicación dieron a la caída del muro de Berlín en 1989, a través de una exposición de imágenes, publicadas por los periódicos más influyentes de España en la época: El País, La Vanguardia y el ABC.
Chaos in driven Alfvén systems: unstable periodic orbits and chaotic saddles
Directory of Open Access Journals (Sweden)
A. C.-L. Chian
2007-01-01
Full Text Available The chaotic dynamics of Alfvén waves in space plasmas governed by the derivative nonlinear Schrödinger equation, in the low-dimensional limit described by stationary spatial solutions, is studied. A bifurcation diagram is constructed, by varying the driver amplitude, to identify a number of nonlinear dynamical processes including saddle-node bifurcation, boundary crisis, and interior crisis. The roles played by unstable periodic orbits and chaotic saddles in these transitions are analyzed, and the conversion from a chaotic saddle to a chaotic attractor in these dynamical processes is demonstrated. In particular, the phenomenon of gap-filling in the chaotic transition from weak chaos to strong chaos via an interior crisis is investigated. A coupling unstable periodic orbit created by an explosion, within the gaps of the chaotic saddles embedded in a chaotic attractor following an interior crisis, is found numerically. The gap-filling unstable periodic orbits are responsible for coupling the banded chaotic saddle (BCS to the surrounding chaotic saddle (SCS, leading to crisis-induced intermittency. The physical relevance of chaos for Alfvén intermittent turbulence observed in the solar wind is discussed.
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.
Ion extraction from a saddle antenna RF surface plasma source
Dudnikov, V.; Johnson, R. P.; Han, B.; Murray, S.; Pennisi, T.; Piller, C.; Santana, M.; Stockli, M.; Welton, R.; Breitschopf, J.; Dudnikova, G.
2015-04-01
Existing RF Surface Plasma Sources (SPS) for accelerators have specific efficiencies for H+ and H- ion generation around 3 to 5 mA/cm2 per kW, where about 50 kW of RF power is typically needed for 50 mA beam current production. The Saddle Antenna (SA) SPS described here was developed to improve H- ion production efficiency and SPS reliability and availability. At low RF power, the efficiency of positive ion generation in the plasma has been improved to 200 mA/cm2 per kW of RF power at 13.56 MHz. Initial cesiation of the SPS was performed by heating cesium chromate cartridges by discharge as was done in the very first versions of the SPS. A small oven to decompose cesium compounds and alloys was developed and tested. 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 power in the plasma and 250 Gauss longitudinal magnetic field. The ratio of electron current to negative ion current was improved from 30 to 2. Stable generation of H- beam without intensity degradation was demonstrated in the AlN discharge chamber for a long time at high discharge power in an RF SPS with an external antenna. Continuous wave (CW) operation of the SA SPS has been tested on the small 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. The extracted collector current can be increased significantly by optimizing the longitudinal magnetic field in the discharge chamber. CW operation with negative ion extraction was tested with RF power up to 1.8 kW from the generator (˜1.2 kW in the plasma) with production up to Ic=7 mA. Long term operation was tested with 1.2 kW from the RF generator (˜0.8 kW in the plasma) with production of Ic=5 mA, Iex ˜15 mA (Uex=8 kV, Uc=14 kV).
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; 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.
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; 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.
Bowl breakout: Escaping the positive region when searching for saddle points
Energy Technology Data Exchange (ETDEWEB)
Pedersen, Andreas [Faculty of Physical Sciences, University of Iceland VR-III, 107 Reykjavík (Iceland); Integrated Systems Laboratory, ETH Zurich, 8092 Zurich (Switzerland); Luiser, Mathieu [Integrated Systems Laboratory, ETH Zurich, 8092 Zurich (Switzerland)
2014-07-14
We present a scheme improving the minimum-mode following method for finding first order saddle points by confining the displacements of atoms to the subset of those subject to the largest force. By doing so it is ensured that the displacement remains of a local character within regions where all eigenvalues of the Hessian matrix are positive. However, as soon as a region is entered where an eigenvalue turns negative all atoms are released to maintain the ability of determining concerted moves. Applying the proposed scheme reduces the required number of force calls for the determination of connected saddle points by a factor two or more compared to a free search. Furthermore, a wider distribution of the relevant low barrier saddle points is obtained. Finally, the dependency on the initial distortion and the applied maximal step size is reduced making minimum-mode guided searches both more robust and applicable.
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.
Jiang, Heping; Jiang, Jiao; Song, Yongli
In this paper, we firstly employ the normal form theory of delayed differential equations according to Faria and Magalhães to derive the normal form of saddle-node-Hopf bifurcation for the general retarded functional differential equations. Then, the dynamical behaviors of a Leslie-Gower predator-prey model with time delay and nonmonotonic functional response are considered. Specially, the dynamical classification near the saddle-node-Hopf bifurcation point is investigated by using the normal form and the center manifold approaches. Finally, the numerical simulations are employed to support the theoretical results.
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.
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.
Song, Q. S.; Yin, G.
2006-01-01
This work establishes sufficient conditions for existence of saddle points in discrete Markov games. The result reveals the relation between dynamic games and static games using dynamic programming equations. This result enables us to prove existence of saddle points of non-separable stochastic differential games of regime-switching diffusions under appropriate conditions.
Baviera, I. (Inmaculada)
2010-01-01
Las políticas de empleo comunitarias se han desarrollado a lo largo del proceso de construcción de la Unión Europea. Desde la Estrategia de Lisboa se ha reforzado la introducción progresiva de planteamientos economicistas para hacer de Europa la economía más competitiva y dinámica del mundo. Sin embargo, estos criterios pretenden recortar ciertas garantías sociales y ponen en peligro los derechos de los trabajadores. El vigésimo aniversario de la caída del muro de Berlín, en gran medida fruto...
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.
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.
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...
Expansion of single-link integrals around a saddle-point configuration
Brihaye, Y.; Taormina, A.
1985-12-01
Considering the single-link integrals arising in the mean-field approach of lattice spin and gauge models, we present a simple method to develop these integrals in powers of a fluctuation around the relevant mean-field saddle-point configurations. We illustrate the method by computing four orders in the large-N limit of the U(N) group integral.
Expansion of single-link integrals around a saddle-point configuration
Energy Technology Data Exchange (ETDEWEB)
Brihaye, Y.; Taormina, A.
1985-12-15
Considering the single-link integrals arising in the mean-field approach of lattice spin and gauge models, we present a simple method to develop these integrals in powers of a fluctuation around the relevant mean-field saddle-point configurations. We illustrate the method by computing four orders in the large-N limit of the U(N) group integral.
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.
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.
Modified saddle-point integral near a singularity for the large deviation function
International Nuclear Information System (INIS)
Long-time-integrated quantities in stochastic processes, in or out of equilibrium, usually exhibit rare but huge fluctuations. Work or heat production is such a quantity, for which the probability distribution function displays an exponential decay characterized by the large deviation function (LDF). The LDF is often deduced from the cumulant generating function through the inverse Fourier transformation. The saddle-point integration method is a powerful technique to obtain the asymptotic results in the Fourier integral, but special care should be taken when the saddle point is located near a singularity of the integrand. In this paper, we present a modified saddle-point method to handle such a difficulty efficiently. We investigate the dissipated and injected heat production in equilibration processes with various initial conditions, for example, where the generating functions contain branch-cut singularities as well as power-law ones. Exploiting the new modified saddle-point integrations, we obtain the leading finite-time corrections for the LDFs, which are confirmed by numerical results. (paper)
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
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.
Ultrasonic depth-sizing errors of crack-like defects in saddle-shaped weld joints
International Nuclear Information System (INIS)
In order to determine crack depth in primarily loop recirculation (PLR) piping of boiling water reactors, ultrasonic angle beam testing using time of flight measurement of the diffracted signal from the crack tip, is employed. There are some power stations in Japan having saddle-shaped weld joints at branch connections in PLR piping. If the angle beam testing is applied without considering curvature of saddle-shaped weld joints, unlike weld joints of straight piping, it can be predicted that determined depth by the typical technique mentioned above contains a geometrical error due to the curvature. This issue has never been discussed in welds of branch connections. This paper deals with this issue with a mockup and phased array inspection system. As a result, the geometrical error is negligibly small in comparison to underlying depth-sizing errors of stress corrosion cracks in authentic stainless steel welds. (author)
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.
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...
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.
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.
A New Choice of the Preconditioner of PHSS Metho d for Saddle Point Problems
Institute of Scientific and Technical Information of China (English)
SUN Jia; WANG Shi-heng; WANG Ke
2015-01-01
Bai, Golub and Pan presented a preconditioned Hermitian and skew-Hermitian splitting(PHSS) method [Numerische Mathematik, 2004, 32: 1-32] for non-Hermitian posi-tive semidefinite linear systems. We improve the method to solve saddle point systems whose (1,1) block is a symmetric positive definite M-matrix with a new choice of the preconditioner and compare it with other preconditioners. The results show that the new preconditioner outperforms the previous ones.
Det-Det correlations for quantum maps: Dual pair and saddle-point analyses
International Nuclear Information System (INIS)
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(set-membership sign)U(N), and studying the correlator ωU(s)=∫dθ vertical bar Z(eiθs) vertical bar2. 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
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.
Exotic Homoclinic Surface of a Saddle-Node Limit Cycle in a Leech Neuron Model
Yooer, Chi-Feng; Wei, Fang; Xu, Jian-Xue; Zhang, Xin-Hua
2011-03-01
We carry out numerical and theoretical investigations on the global unstable invariant set (manifold) of a saddle-node limit cycle in a leech heart interneuron model. The corresponding global bifurcation is accompanied by an explosion of secondary bifurcations of limit cycles and the emergence of loop-shaped bifurcation structures. The dynamical behaviors of the trajectories of the invariant set are very complicated and can only be partially explained by existing theories.
Exotic Homoclinic Surface of a Saddle-Node Limit Cycle in a Leech Neuron Model
International Nuclear Information System (INIS)
We carry out numerical and theoretical investigations on the global unstable invariant set (manifold) of a saddle-node limit cycle in a leech heart interneuron model. The corresponding global bifurcation is accompanied by an explosion of secondary bifurcations of limit cycles and the emergence of loop-shaped bifurcation structures. The dynamical behaviors of the trajectories of the invariant set are very complicated and can only be partially explained by existing theories. (general)
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 ...
Patrnogić Vesna; Todorović Aleksandar; Šćepanović Miodrag; Radović Katarina; Vesnić Jelena; Grbović Aleksandar
2013-01-01
Background/Aim. Different types of dental restorations are used for the therapy of unilateral free-end saddle edentulism. Unilateral complex partial denture is one of the indications for the Kennedy class II partial edentulism. The abscence of major connector and denture plate is an advantage compared to the conventional restorations, because of better comfort and shorter period of adaptation. The aim of the study was to analyse the influence of free-end saddle length change on the beha...
Susmita Bhattacharyya; Subrata Bisai; Hirak Biswas; Mandeep Kumar Tiwary; Suchismita Mallik; Swarna Mukul Saha
2015-01-01
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 s...
Directory of Open Access Journals (Sweden)
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
Oscar Pérez de la Fuente
2011-01-01
RESUMEN Es artículo analiza el caso de los centinelas del muro de Berlín que disparaban y mataron a algunas personas –que querían pasar la frontera-, amparados por una interpretación del Derecho de la RDA. Algunos años después de la unificación alemana, el Tribunal Constitucional condenó aquellos soldados por asesinato con el argumento que se trataba de Derecho “extremadamente injusto”. Esta es una forma particular de aplicación de la fórmula de Radburch. El objetivo de este artículo es est...
Directory of Open Access Journals (Sweden)
Oscar Pérez de la Fuente
2011-06-01
Full Text Available RESUMEN Es artículo analiza el caso de los centinelas del muro de Berlín que disparaban y mataron a algunas personas –que querían pasar la frontera-, amparados por una interpretación del Derecho de la RDA. Algunos años después de la unificación alemana, el Tribunal Constitucional condenó aquellos soldados por asesinato con el argumento que se trataba de Derecho “extremadamente injusto”. Esta es una forma particular de aplicación de la fórmula de Radburch. El objetivo de este artículo es estudiar el caso de los centinelas del Muro de Berlín bajo la perspectiva del la Filosofía del Derecho, particularmente en la controversia entre positivismo y iusnaturalismo. En este sentido, se comparan los enfoques de Kelsen y Radburch sobre el Derecho nazi. Y también se estudia la polémica Hart Fuller sobre el caso de “delator rencoroso”. ABSTRACT This article analyzes the case of the border guards of the Berlin Wall that have shot and killed some people -who wanted pass the frontier- and those soldiers were protected by some legal interpretation under the German Democratic Republic Law. Some years after the German unification, the Constitutional Court condemned those soldiers for murder with the argument that that was an “extremely unjust” Law. This was a particular form of application of the Radburch’s formula. The objective of this article is studying the case of the Berlin Wall border guards under the perspective of the Philosophy of Law, particularly the controversy between positivism and iusnaturalism. In this sense, they are compared Kelsen and Radbruch approaches on Nazi law. And also it’s studied the Hart-Fuller polemics on the ‘grudge infomer’ case.
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.
Controlling Unknown Saddle Type Steady States of Dynamical Systems with Latency in the Feedback Loop
DEFF Research Database (Denmark)
Tamasevicius, Arunas; Bumeliene, Skaidra; Tamaseviciute, Elena;
2009-01-01
We suggest an adaptive control technique for stabilizing saddle type unstable steady states of dynamical systems. The controller is composed of an unstable and a stable high-pass filters operating in parallel. The mathematical model is considered analytically and numerically. The conjoint...... controller is sufficiently robust to time latencies in the feedback loop. In addition, it is not sensitive to the damping parameters of the system and is relatively fast. Experiments have been performed using a simplified version of the electronic Young-Silva circuit imitating behavior of the Duffing...
Globally Proper Saddle Point in Ic-Cone-Convexlike Set-Valued Optimization Problems
Institute of Scientific and Technical Information of China (English)
Guo Lin YU; San Yang LIU
2009-01-01
The existence conditions of globally proper efficient points and a useful property of iccone-convexlike set-valued maps are obtained. Under the assumption of the ic-cone-convexlikeness, the optimality conditions for globally proper efficient solutions are established in terms of Lagrange multipliers. The new concept of globally proper saddle-point for an appropriate set-valued Lagrange map is introduced and used to characterize the globally proper efficient solutions. The results which are obtained in this paper are proven under the conditions that the ordering cone need not to have a nonempty interior.
Saddle-point approximation for M-ary phase-shift keying with adjacent satellite interference
Yue, O.
1980-09-01
As the geosynchronous orbit for satellite communication becomes increasingly crowded, the effect of adjacent satellite interference is of primary concern. The saddle-point approximation technique for evaluating the error probability of M-ary PSK systems with adjacent satellite interference is described. In comparison with previous methods, this technique has the advantages of both computational simplicity and accuracy. Results include a sample calculation to study the effect of fading on the uplink of a 12/14-GHz quadraphase-shift-keying system with 3-degree satellite spacings and 3-m earth stations.
Initiation to mould calculus through the example of saddle-node singularities
Sauzin, David
2007-01-01
This article proposes an initiation to \\'Ecalle's mould calculus, a powerful combinatorial tool which yields surprisingly explicit formulas for the normalising series attached to an analytic germ of singular vector field. This is illustrated on the case of saddle-node singularities, generated by two-dimensional vector fields which are formally conjugate to Euler's vector field $x^2\\frac{\\pa}{\\pa x}+(x+y)\\frac{\\pa}{\\pa y}$, and for which the formal normalisation proves to be resurgent in $1/x$.
Saddle point condition for D minus sup 3 He tokamak fusion reactor
Energy Technology Data Exchange (ETDEWEB)
Mitarai, O. (Kumamoto Inst. of Technology, Dept. of Electrical Engineering, Ikeda 4-22-1, Kumamoto 860 (JP)); Hirose, A.; Skarsgard, H.M. (Univ. of Saskatchewan, Dept. of Physics Sasakatoon, Saskatchewan, S7N 0W0 (CA))
1991-03-01
In this paper the concept of a generalized ignition contour map, showing {bar P}{sub ht}T{sup 2}{sub E}, NT{sub E}, and T, is used to study the ignition criterion for a D{minus}{sup 3}He fusion reactor with plasma temperature and density profiles. Direct heating scenarios to the D {minus} {sup 3}He ignition regime without the help of deuterium-tritium burning are considered. The machine size and enhancement factor for the confinement time required to reach D {minus} {sup 3}He ignition can be simple determined by comparing the height of the operation path with Goldston L-mode scaling and the height of the generalized saddle point. A confinement enhancement factor of 2 to 3 is required in the case of a large plasma current (30 to 80 MA) in a small-aspect-ratio tokamak. On the other hand, for a small plasma current ({approx lt} 10 MA), large-aspect-ratio tokamak, an enhancement factor of 5 to 6 is necessary to reach ignition. Fuel dilution effects by fusion products and impurities, the confinement degradation effect due to 14-MeV protons, and the operation paths are also considered. To lower the height of the saddle point, and hence the auxiliary heating power, we optimize the fuel composition and examine operation in the hot ion mode.
Parametric CAD and Fea Model of a Saddle Tapping Tee
DEFF Research Database (Denmark)
A. Kristensen, Anders Schmidt; Lund Jepsen, Kristian
2007-01-01
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...... required and relevant user-defined parameter on the Saddle Tapping Tee from a single Excel spreadsheet in both the CAD model and the FE model. A full 3D CAD model is effectively generated for dimensions in the range from NPS ½ to NPS 24 and FEA can be performed to provide documentation of the behaviour...
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...
广义中心-细鞍点的若干公式%The Formula of Generalized Center-Weak Saddle
Institute of Scientific and Technical Information of China (English)
万维明; 迟晓恒
2002-01-01
In this paper, a problem of center-weak focus of a general system of degree n is transformed into a problem of generalized center-weak saddle. It offers: (1) the calculating formula of the saddle values of the former 4 orders in the general system of degree three; (2) some calculating formulae of the saddle values in the general homogeneous system of degree n.The problem of center-focus(saddle) plays an important role in the qualitative theory of ordinary differential equations. However, since the calculations are difficult, the results have not been satisfactory. On the basis of the author's work, Northeast. Math. J., 13(4)(1997), 487-494, the paper offers some calculating formulae of the saddle values.
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.
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.
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.
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...
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.
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.
2012-05-08
... desired conditions of the Forest Plan, and to facilitate the transition to a sustainable wood product... respond to the goals and objectives identified by the Forest Plan to guide timber management to support... Forest Service Ketchikan-Misty Fiords Ranger District; Tongass National Forest; Alaska; Saddle...
Directory of Open Access Journals (Sweden)
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.
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.
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.
Characteristics of friction between cable and saddle%缆索与鞍座间的摩擦特性
Institute of Scientific and Technical Information of China (English)
周凌远; 李乔
2011-01-01
The reliability of anti-sliding between saddle and main cable is the key to insure the safety of suspension bridges. Model test was carried on for determining friction factor between main cable and saddle. In the process of the test, the influence of actual contact stress between them on friction factor was taken into consideration. The friction factor between single-strand cable and the saddle and that between multi-strand cable and saddle of the Taizhou Yangtze bridge were obtained with the model test. The main origins of influence factor on these friction factors and their deviation from actual value on this bridge were explored. The real friction factor between cable and saddle on this bridge was evaluated according to theoretical analysis. The result of test and theoretical analysis showed that the friction factor between saddle and multi-strand cable was obviously larger than that between saddle and single-strand cable.%缆索与主鞍座间抗滑移稳定是保障大跨度悬索桥安全的关键,对主缆与鞍座间摩擦系数进行模型试验.在试验中,考虑实桥在使用阶段索股的主缆与鞍座间的实际接触应力对摩擦系数的影响,试验得到泰州长江大桥单索股与鞍座、多索股与鞍座间的摩擦系数.对影响缆索与鞍座间摩擦系数的主要原因以及模型试验测试值与实桥摩擦系数之间的关系开展探讨,通过理论分析并计算出实桥鞍座与主缆间存在的实际摩擦系数值.试验测试和理论分析结果显示,鞍座与多索股间的摩擦系数值明显大于与单索股的摩擦系数值.
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Patrnogić Vesna
2013-01-01
Full Text Available Background/Aim. Different types of dental restorations are used for the therapy of unilateral free-end saddle edentulism. Unilateral complex partial denture is one of the indications for the Kennedy class II partial edentulism. The abscence of major connector and denture plate is an advantage compared to the conventional restorations, because of better comfort and shorter period of adaptation. The aim of the study was to analyse the influence of free-end saddle length change on the behaviour of unilateral complex partial denture supporting structures. Methods. Stress levels of the canine and the first premolar as retentional teeth and the attachments were tested under the influence of physiological forces with the loading point shifting distally in relation to the saddle length change. A virtual real size 3D model of the fixed part of the restoration (the canine and the first premolar with milled crowns was created using the CATIA computer program. It was connected to the mobile part of partial denture with the SD snap in latch attachment. Mobile part of the restoration was designed in the region of 2, 3 and 4 lateral teeth (second premolar, first, second and third molar. By using the finite element method (FEM stress levels analysis was performed under the load of physiological forces of 150 N in the free-end saddle teeth zone. Results. The results of analysis show that physiological forces cause a different stress distribution on the abutment teeth and the attachment, depending on the saddle length. Conclusion. The stress level values obtained for the abutment teeth as well as the attachment are far lower than the marginal ones. The behaviour of the system changes under this defined stress, but no plastic deformation occurs.
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.
Back in the saddle: large-deviation statistics of the cosmic log-density field
Uhlemann, C.; Codis, S.; Pichon, C.; Bernardeau, F.; Reimberg, P.
2016-08-01
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 per cent compared to the numerical integration, regardless of the density under consideration and in excellent agreement with N-body simulations for a wide range of densities. This formalism should prove valuable for accurately probing the quasi-linear scales of low-redshift surveys for arbitrary primordial power spectra.
[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.
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.
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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.
[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. PMID:12152425
A smooth landscape: ending saddle point inflation requires features to be shallow
International Nuclear Information System (INIS)
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
Energy Technology Data Exchange (ETDEWEB)
Cerrada, Lucia [Departamento de Matematica Aplicada, EUITI, Universidad Politecnica de Madrid, Ronda de Valencia 3, 28012 Madrid (Spain); ETS de Ingenieria ICAI, Universidad Pontificia Comillas de Madrid, Alberto Aguilera 25, 28015 Madrid (Spain); San Martin, Jesus, E-mail: jsm@dfmf.uned.e [Departamento de Matematica Aplicada, EUITI, Universidad Politecnica de Madrid, Ronda de Valencia 3, 28012 Madrid (Spain); Departamento de Fisica Matematica y Fluidos, UNED, Senda del Rey 9, 28040 Madrid (Spain)
2011-04-25
In this Letter, it is shown that from a two region partition of the phase space of a one-dimensional dynamical system, a p-region partition can be obtained for the CRL...LR...R orbits. That is, permutations associated with symbolic sequences are obtained. As a consequence, the trajectory in phase space is directly deduced from permutation. From this permutation other permutations associated with period-doubling and saddle-node bifurcation cascades are derived, as well as other composite permutations. - Research highlights: Symbolic sequences are the usual topological approach to dynamical systems. Permutations bear more physical information than symbolic sequences. Period-doubling cascade permutations associated with original sequences are obtained. Saddle-node cascade permutations associated with original sequences are obtained. Composite permutations are derived.
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.
Zhang, Jian-zu; He, Li-Ming; Zhu, Yun-Xia
2005-01-01
In the combination of crossed electric and magnetic fields and the Coulomb field of the atomic nucleus the spectrum of the Rydberg electron in the vicinity of the Stark saddle-point are investigated at a quantum mechanical level. The results expose a quantum anomaly dissociation: quasibound states near and above the saddle-point ionization limit predicted at the semi-classical level disappear at a quantum mechanical level.
Dimensional design of saddle-form superconductor field winding for turbogenerators
Energy Technology Data Exchange (ETDEWEB)
Khutoretskiy, G.M.; Varshavskiy, V.D.; Prazdnikov, V.I.
1983-12-01
The design of saddle-form superconductor field windings for cryogenic turbogenerators involves calculating a three-dimensional magnetic field and optimizing the coil dimensions. This is done analytically, with subsequent refinement by numerical methods. The superconducting material is assumed to be a composite one and to retain its functional properties within some ranges of magnetic induction B, current density j, and absolute temperature T. At a given temperature T = T/sub 0/ = const the sufficient condition for normal operation is defined as j/sub c/ = jk = f B/sub max/ (j/sub c/ - critical current density, k > 1 current safety factor, B/sub max/ - maximum magnetic induction. The magnetic field in both the slotted zone and the end zone is calculated on the basis of corresponding Laplace and Poisson equations for the magnetic vector potential, with appropriate boundary conditions. Design analysis includes determining the dependence of the safety factor on the ratio of wound surface area to total surface area of the rotor for given coil heights, then comparing various coil configurations for some nominal amplitude of the fundamental Fourier component of magnetic induction at the stator bore, assuming a uniform current density distribution over the winding zone which will ensure that amplitude of B/sub 1/, and calculating the safety factor for each configuration. The magnetic field is evaluated by the methods of finite differences and sequential upper relaxation, assuming a magnetic vector potential with only an axial component. Design optimization by variation of independent dimensional parameters is done by linear programming. The algorithm yields first the optimum ratio of wound surface area to total surface area, one which will result in the maximum safety factor and which should serve as a basis for further design. 5 references, 4 figures.
Sanan, P.; Schnepp, S. M.; May, D.; Schenk, O.
2014-12-01
Geophysical applications require efficient forward models for non-linear Stokes flow on high resolution spatio-temporal domains. The bottleneck in applying the forward model is solving the linearized, discretized Stokes problem which takes the form of a large, indefinite (saddle point) linear system. Due to the heterogeniety of the effective viscosity in the elliptic operator, devising effective preconditioners for saddle point problems has proven challenging and highly problem-dependent. Nevertheless, at least three approaches show promise for preconditioning these difficult systems in an algorithmically scalable way using multigrid and/or domain decomposition techniques. The first is to work with a hierarchy of coarser or smaller saddle point problems. The second is to use the Schur complement method to decouple and sequentially solve for the pressure and velocity. The third is to use the Schur decomposition to devise preconditioners for the full operator. These involve sub-solves resembling inexact versions of the sequential solve. The choice of approach and sub-methods depends crucially on the motivating physics, the discretization, and available computational resources. Here we examine the performance trade-offs for preconditioning strategies applied to idealized models of mantle convection and lithospheric dynamics, characterized by large viscosity gradients. Due to the arbitrary topological structure of the viscosity field in geodynamical simulations, we utilize low order, inf-sup stable mixed finite element spatial discretizations which are suitable when sharp viscosity variations occur in element interiors. Particular attention is paid to possibilities within the decoupled and approximate Schur complement factorization-based monolithic approaches to leverage recently-developed flexible, communication-avoiding, and communication-hiding Krylov subspace methods in combination with `heavy' smoothers, which require solutions of large per-node sub-problems, well
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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
Georgiev, Mladen
2006-01-01
The F' center in an alkali halide forms when an anion vacancy traps two electrons which is the prerequisite of a diatomic molecule. Indeed, the center may displace left or right along in a (110) plane, due to its coupling to the B_{1u} vibrational mode of polarization respectively. On jumping from the initial position to the final position the F' center passes through a saddle point which configuration is molecule-like being conformed by two neighboring semi-vacancies along . Each semi-vaca...
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.
Wissman, J.; Finkenauer, L.; Deseri, L.; Majidi, C.
2014-10-01
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 PDMS composite. By accurately modeling electromechanical coupling in a soft-matter DEA, this theory can inform improvements in design and fabrication.
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.
Fumeron, Sébastien; Moraes, Fernando; Pereira, Erms
2016-09-01
The physics of light interference experiments is well established for nematic liquid crystals. Using well-known techniques, it is possible to obtain important quantities, such as the differential scattering cross section and the saddl-splay elastic constant K24. However, the usual methods to retrieve the latter involve adjusting of computational parameters through visual comparisons between the experimental light interference pattern or a (2) H-NMR spectral pattern produced by an escaped-radial disclination, and their computational simulation counterparts. To avoid such comparisons, we develop an algebraic method for obtaining of saddle-splay elastic constant K24. Considering an escaped-radial disclination inside a capillary tube with radius R0 of tens of micrometers, we use a metric approach to study the propagation of the light (in the scalar wave approximation), near the surface of the tube and to determine the light interference pattern due to the defect. The latter is responsible for the existence of a well-defined interference peak associated to a unique angle [Formula: see text] . Since this angle depends on factors such as refractive indexes, curvature elastic constants, anchoring regime, surface anchoring strength and radius R0, the measurement of [Formula: see text] from the interference experiments involving two different radii allows us to algebraically retrieve K24. Our method allowed us to give the first reported estimation of K24 for the lyotropic chromonic liquid crystal Sunset Yellow FCF: K 24 = 2.1 pN. PMID:27589980
International Nuclear Information System (INIS)
To explore mechanism for the effect of saddle-like dose-response curve, the relationship of irradiation-vacuum stress, and irradiation-salt stress, was investigated with rice seeds irradiated to 60-560 Gy by 60Co γ-rays. The dose-response curve was simulated based on seedling height data, which showed obedient to linear-quadratic model. During germination,the irradiated rice seeds were stressed by 10-3 Pa vacuum, or by NaCl in different concentrations. After that, the dose-response curve manifested a saddle-like shape. The results indicate that while low dose irradiation could retard seedling growth synergistically with vacuum stress and salt stress, it could also induce adaptive response upon vacuum stress and salt stress. Low dose irradiation induced adaptive response upon environmental adverse factors could contribute to the mechanism for the effect of saddle-like dose-response curve. (authors)
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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.
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.
Yooer, Chi-Feng; Xu, Jian-Xue; Zhang, Xin-Hua
2009-08-01
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.
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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
Hwang, Jonathan; Zhao, Qi; Yang, Zhu L; Wang, Zheng; Townsend, Jeffrey P
2015-08-01
The relation between ecological and genetic divergence of Helvella species (saddle fungi) has been perplexing. While a few species have been clearly demonstrated to be ectomycorrhizal fungi, ecological roles of many other species have been controversial, alternately considered as either saprotrophic or mycorrhizal. We applied SATé to build an inclusive deoxyribonucleic acid sequence alignment for the internal transcribed spacers (ITS) of annotated Helvella species and related environmental sequences. Phylogenetic informativeness of ITS and its regions were assessed using PhyDesign. Mycorrhizal lineages present a diversity of ecology, host type and geographic distribution. In two Helvella clades, no Helvella ITS sequences were recovered from root tips. Inclusion of environmental sequences in the ITS phylogeny from these sequences has the potential to link these data and reveal Helvella ecology. This study can serve as a model for revealing the diversity of relationships between unculturable fungi and their potential plant hosts. How non-mycorrhizal life styles within Helvella evolved will require expanded metagenomic investigation of soil and other environmental samples along with study of Helvella genomes. PMID:26033481
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...
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)
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.
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.
Shahroosvand, Hashem; Zakavi, Saeed; Sousaraei, Ahmad; Eskandari, Mortaza
2015-03-01
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
Energy Technology Data Exchange (ETDEWEB)
Mielke, Steven L.; Schwenke, David; Peterson, Kirk A.
2005-06-08
We present a detailed ab initio study of the effect that the Born–Oppenheimer diagonal correction (BODC) has on the saddle point properties of the H3 system and its isotopomers. Benchmark values are presented that are estimated to be within 0.1 cm–1 of the complete configuration interaction limit. We consider the basis set and correlation treatment requirements for accurate BODC calculations, and both are observed to be more favorable than for the Born–Oppenheimer energies. The BODC raises the H + H2 barrier height by 0.1532 kcal/mol and slightly narrows the barrier—with the imaginary frequency increasing by ~2%.
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. PMID:25987120
Institute of Scientific and Technical Information of China (English)
Yue WU; Zhao-qing CHEN; Xiao-ying SUN
2015-01-01
The aero-elastic instability mechanism of a tensioned membrane structure is studied in this paper. The response and wind velocities above two closed-type saddle-shaped tensioned membrane structures, with the same shape but different pre-tension levels, were measured in uniform flow and analyzed. The results indicate that, for most wind directions, several vibration modes are excited and the amplitude and damping ratio of the roof slowly increase with the on-coming flow velocity. However, for particular wind directions, only one vibration mode is excited, and the amplitude and damping ratio of the vibration mode increase slowly with the on-coming flow velocity. The aero-elastic instability is caused by vortex-induced resonance. On ex-ceeding a certain wind speed, the amplitude of the roof vibration increases sharply and the damping ratio of the vibration mode decreases quickly to near zero; the frequency of the vortex above the roof is locked in by the vibration within a certain wind velocity range; the amplitudes of the roof in these wind directions reach 2–4 times the amplitudes for other wind directions. The reduced critical wind speeds for the aero-elastic instability of saddle-shaped membrane structures at the first two modes are around 0.8–1.0.%目的：明确张拉膜结构风致气弹响应特征及气弹失稳机理。 创新点：1.采用无接触测量技术设计鞍形张拉膜结构气弹模型风洞试验；2.研究鞍形张拉膜结构的气弹响应特征；3.给出鞍形张拉膜结构的失稳机理。 方法：1.在风洞中测量两个形状相同但预张力不同的封闭式鞍形张拉膜结构气弹模型在不同风速下的均匀流中的位移响应及膜面上方不同高度的风速时程；2.通过对位移响应及风速时程进行分析，明确结构的响应随风速变化特征及气弹失稳原因。 结论：1.膜结构在风荷载作用下变形到平衡位置，并围绕该平衡位置
Directory of Open Access Journals (Sweden)
Julio Francisco Kleinpaul
2012-12-01
Full Text Available O objetivo deste estudo foi analisar a influência da altura do selim sobre a cinemática da coluna lombar durante o ciclismo. Foram avaliados oito ciclistas recreacionais, na situação usual (auto ajustada e na situação de selim ajustado, com carga de 150 W, utilizando-se avaliação cinemática bidimensional em um ciclosimulador. Foram mensurados os ângulos de flexão, inclinação lateral e rotação da coluna lombar. A flexão da lombar foi maior na situação de selim ajustado, enquanto que a inclinação e a rotação da lombar foram maiores na situação de ajuste usual. Quanto ao comportamento ao longo do ciclo de pedalada, ocorreram dois ciclos de flexão-extensão durante um ciclo completo do pé-de-vela, e apenas um ciclo de inclinação lateral ou de rotação. As maiores diferenças acorreram no início, meio e fim do ciclo. O ajuste equivocado do selim não acarreta alterações na cinemática da coluna lombar.The aim of this study was to analyze the influence of saddle height on the kinematics of the lumbar spine during cycling. Eight recreational cyclists were assessed in an usual situation (self-selected and the situation of saddle properly adjusted while pedaling with a load set at 150 W. Using two-dimensional kinematic the angles of flexion, lateral inclination and rotation of the lumbar spine were computed. The flexion was greater in the adjusted position whereas the highest average tilt and rotation angles occurred in the usual position. There were two cycles of flexion-extension observed during a complete pedaling cycle, and only one cycle of lateral inclination and rotation. The major differences were observed at early, middle and end of the pedaling cycle. The mismanagement of the saddle did not involve significant changes in the kinematics of the lumbar spine for the conditions tested.
Mielke, Steven L.; Schwenke, David W.; Peterson, Kirk A.
2005-06-01
We present a detailed ab initio study of the effect that the Born-Oppenheimer diagonal correction (BODC) has on the saddle-point properties of the H3 system and its isotopomers. Benchmark values are presented that are estimated to be within 0.1cm-1 of the complete configuration-interaction limit. We consider the basis set and correlation treatment requirements for accurate BODC calculations, and both are observed to be more favorable than for the Born-Oppenheimer energies. The BODC raises the H+H2 barrier height by 0.1532kcal/mol and slightly narrows the barrier—with the imaginary frequency increasing by ˜2%.
Directory of Open Access Journals (Sweden)
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.
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.
Martin, P; Cheze, L; Pourcelot, P; Desquilbet, L; Duray, L; Chateau, H
2016-05-01
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. PMID:26947029
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.
Jang, H K; Lee, Y S; Whangbo, S W; Whang, C N; Yoo, Y Z; Kim, H G
1999-01-01
Hydrogenated amorphous carbon nitride [a-C:H(N)] films were deposited using dc saddle-field plasma-enhanced chemical-vapor deposition. The structural and the compositional changes induced in the films by the different flow-rate ratios of N sub 2 to CH sub 4 (n sub N sub 2 /n sub C sub H sub sub 4) were investigated using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The deposition rate of the films abruptly decreased upon increasing the n sub N sub 2 /n sub C sub H sub sub 4 ratio. However, for n sub N sub 2 /n sub C sub H sub sub 4 >0.5, the deposition rate slightly decreased with increasing n sub N sub 2 /n sub C sub H sub sub 4. The ratio of N to C (N/C) of the films saturated to 0.25 with increasing n sub N sub 2 /n sub C sub H sub sub 4. The numbers of N-H and C ident to N bonds in the films increased with increasing n sub N sub 2 /n sub C sub H sub sub 4 , but the number of C-H bonds decreased. The optical band-gap energy of the films decreased from 2.53 eV to 2.3 eV as t...
Alam, Aftab; Johnson, D. D.
2009-09-01
Site-centered, electronic-structure methods use an expansion inside nonoverlapping “muffin-tin” (MT) spheres plus an interstitial basis set. As the boundary separating the more spherical from nonspherical density between atoms, the “saddle-point” radii (SPR) in the density provide an optimal spherical region for expanding in spherical harmonics, as used in augmented plane wave, muffin-tin orbital, and multiple-scattering [Korringa, Kohn, and Rostoker (KKR)] methods. These MT-SPR guarantee unique, convex Voronoi polyhedra at each site, in distinction to Bader topological cells. We present a numerically fast, two-center expansion to find SPR a priori from overlapping atomic charge densities, valid also for disordered alloys. We adopt this MT-SPR basis for KKR in the atomic sphere approximation and study (dis)ordered alloys with large differences in atomic size (fcc CoPt and bcc CrW). For this simple and unique improvement, we find formation energies and structural parameters in strikingly better agreement with more exact methods or experiment, and resolve issues with former results.
Kügler, Philipp
2016-01-01
Early afterdepolarizations (EADs) are pathological oscillations in cardiac action potentials during the repolarization phase and may be caused by drug side effects, ion channel disease or oxidative stress. The most widely observed EAD pattern is characterized by oscillations with growing amplitudes. So far, its occurence has been explained in terms of a supercritical Hopf bifurcation in the fast subsystem of the action potential dynamics from which stable limit cycles with growing amplitudes emerge. The novel contribution of this article is the introduction of two alternative explanations of EAD genesis with growing amplitudes that do not involve stable limit cycles in fast subsystems. In particular, we demonstrate that EAD patterns with growing amplitudes may alternatively arise due to a delayed subcritical Hopf bifurcation or an unstable manifold of a saddle focus fixed point in the full fast-slow system modelling the action potential. Our work extends the list of possible dynamical EAD mechanisms and may contribute to a classification of drug effects in preclinical cardiotoxicity testing. PMID:26977805
Institute of Scientific and Technical Information of China (English)
李莉; 张运强; 冯少华
2015-01-01
对轴向管口的管口载荷和地震参数对小直径卧式换热器的鞍座和地脚螺栓的影响进行了分析，并为类似工况下设备的设计和计算提供了参考。%The influences of nozzle loads and seismic load to the saddle and anchor bolts in small diameter horizontal heat exchanger were analyzed in this article, which can be referenced in the design and calculation for the equipment with similar working conditions.
Institute of Scientific and Technical Information of China (English)
苏萱; 徐雷鸣
2016-01-01
目的：探讨特发性腕管综合征（CTS）患者鞍状腕横韧带的MRI特征。方法回顾性分析经临床诊断为特发性CTS的21例患者（22个腕关节）作为特发性CTS组；无腕管综合征症状且无腕横韧带及其掌侧软组织病变的32例其他腕部疾病患者（33个腕关节）作为对照组。均行矢状面、横轴面腕关节MRI平扫。观察腕横韧带形态，判断腕横韧带是否为马鞍形，并计算腕横韧带掌凹曲率和正中神经压缩率。采用χ2检验比较2组患者腕横韧带形态的差异，采用非参数秩和检验比较2组患者腕横韧带掌凹曲率的差异，采用Pearson相关分析评价特发性CTS患者腕横韧带掌凹曲率与正中神经的压缩率的相关性。结果特发性CTS患者矢状面像上，马鞍形腕横韧带向掌侧凹，最凹点常位于钩骨钩水平。以马鞍形腕横韧带下凹0.25 mm为标准，马鞍形腕横韧带31例（特发性CTS患者20例、对照组11例），非马鞍形腕横韧带24例（特发性CTS 2例，对照组22例），2组患者腕横韧带形态的差异有统计学意义（χ2=17.791，P<0.01）。特发性CTS和对照组患者的腕横韧带掌凹曲率中位数分别为8.49%和0.00%，差异有统计学意义（Z=-4.79，P<0.01）。特发性CTS患者正中神经层面，腕横韧带掌凹曲率[（7.88±4.28）%）]与正中神经压缩率[（39.36±19.43）%]呈正相关（r=0.714，P<0.01）。结论马鞍形腕横韧带是特发性CTS患者的特征表现，腕横韧带矢状面掌凹屈率和正中神经压缩百分比有助于精确诊断。%Objective To explore the MRI characteristics of saddle transverse carpal ligament (TCL)of patients with idiopathic carpal tunnel syndrome (CTS). Methods The clinical diagnosis of 21 cases of idiopathic CTS patients (22 wrists) were retrospectively analyzed and as the idiopathic CTS group. Thirty two patients without CTS symptoms or TCL and volar soft tissue lesions (33 wrist
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)
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
用鞍点保证拓扑正确的快速等值面提取技术%Fast iso-surface extraction method using saddle to ensure topology correct
Institute of Scientific and Technical Information of China (English)
黄连杰; 李纳
2011-01-01
等值面提取是研究三维数据场可视化的有效方法.针对已有的一些等值面提取算法存在的二义性问题,提出了用鞍点保证拓扑正确的快速等值面提取算法.用二线性插值和三线性插值函数来近似计算立方体表面和内部点的值,根据立方体中面鞍点和体鞍点个数的不同,将立方体剖分成不同数目的四面体.这种剖分只和原始数据的属性有关,与给定的等值无关,因此在数据不变的情况下只需要剖分一次.最后,用分层分组的方法将四面体分类到不同组中,避免在等值面提取过程中访问那些不合有等值面的四面体,从而提高了算法的速度.该算法在等值平滑变化或是随机变化时都能保持良好的特性.%Iso-surface extraction is an effective manner to study the visualization of three-dimensional data field.To solve the ambiguity question of the existing iso-surface extraction algorithms,a fast iso-surface extraction method which uses saddle to ensure the topology correct is proposed.The accurate iso-surface in the interior of cube is constructed by using the bilinear and the bilinear interpolant method.According to the number of saddle in cube, the cube is tessellated to several tetrahedral cell.This method is only relate to the properties of original data rather than the iso-value, so the cube is only tessellated once when the original data are not changed.Finally, tetrahedral cells are classified into different classes by the class group mehtod.so that only the tetrahedral cell which is intersected with the given iso-surface is visited, the speed of extration is quite improved.Whether the iso-value is smoothly changed or randomly changed,the algorithm is able to maintain a good character.
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.
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
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 ...
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.
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.
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)
李如源
2016-01-01
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.%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。
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 .
International Nuclear Information System (INIS)
A total of 24 isolates of Bacillus thuringiensis (Berliner), resistant to a γ-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 LC50's of these isolates to B. mori ranged from 1.6 X 105 to 6.0 X 103 spores/mL or from 5.9 to 0.3 μg cellular protein/mL. The irradiation treatment produced isolates which were significantly more toxic to P. xylostella (LC50 4 spores/mL or 3.7 μg cellular protein/mL) and/ or less toxic to B. mori (LC50 > 2.3 X 104 spores/mL or 1.0 μg cellular protein/mL) than the parent commercial strain
Berlín, coneixement d'una metròpoli
Jiménez Sagols, Neus
2006-01-01
El treball és un anàlisi de l'evolució històrica de la capital alemanya i molt especialment de la seva etapa més recent. Consisteix en dos parts clarament diferenciades, la primera de les quals tracta sobre la història urbana prèvia al 1989, data de la caiguda del mur, on es veuen capítols tant interessants com l'arribada de la industrialització a la ciutat, el modernisme, o la guerra freda. La segona part s'ha dedicat a analitzar els darrers quinze anys de canvis que la ciutat ha sofert a tr...
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.
Institute of Scientific and Technical Information of China (English)
郭济; 阮欣; 阮静
2012-01-01
Compared to the traditional suspension bridges with only two pylons, the anti-sliding issue of the saddle on middle pylon is the key problem for three-pylon suspension bridges, which is not clearly presented in existing researches. The basic mechanical model between the middle pylon saddle and the main cable shows that the unbalanced live load is the most important factor for this issue. Because of the obvious geometric nonlinear effect in suspension bridges, the nonlinear influence of vehicle loads on this issue was analyzed. Then based on live load models in various codes, the safety assessment for anti-sliding performance between the main cable and the middle tower saddle was given. The result indicates that the middle pylon can be safe under live loads of various codes. However, the corresponding anti-sliding safety margins are not identical, since different load standards. So further additional studies for refined assessment results based on the real work station are needed.%中间塔鞍座抗滑安全是三塔悬索桥设计的关键问题之一,其特点与传统两塔悬索桥不同.根据鞍座与主缆间的抗滑力学模型,中间塔两侧的不平衡车辆荷载是导致主缆与鞍座滑移的主要因素.由于三塔悬索桥体系存在明显的几何非线性特性,通过分析明确了对于中间塔抗滑问题,不考虑车辆荷 .载的几何非线性是偏安全的,于是可选用基于叠加原理的线性理论计算车辆荷载效应.基于规范车辆荷载模型的中间塔鞍座抗滑安全评估表明,不同规范标准下的车辆荷载都能保证中间塔鞍座的抗滑安全,但相应的抗滑安全水平存在差异.因此为获取更加精细化的评估结果,有必要在桥梁实际工作状态下开展进一步的研究.
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.
International Nuclear Information System (INIS)
The hydrodynamic and matter transfer parameters has been studied on absorption columns destined to trap iodine issued of spent fuel reprocessing plants. These columns have different packing - Raschig rings (glass, ceramic, PVC, steel) - Berl saddles (ceramic) - Weaved metallic thread (steel). The effect of dimension and of packing structure on gas pressure drop and on liquid holdup has been evaluated. The partial transfer coefficients of I2-Air-NaOH system has been the object of an experimental study. This system can be simulated by CO2-Air-NaOH system
Desobediencia Civil Indígena: El pueblo Nasa y el incidente del Cerro Berlín
Ballesteros Peluffo, Gilma Liliana
2016-01-01
El artículo tiene el objetivo de revelar formas espontáneas de desobediencia civil, en la que los indígenas se manifiestan en contra de una postura institucional, como la guerra, a través de acciones noviolentas. Sus manifestaciones no solo señalan las injusticias que trae consigo el ejercicio de la violencia, sino que su postura invita a reflexionar sobre la actitud de los ciudadanos frente a la organización para la transformación positiva, la defensa de los derechos y el rechazo a la guerra...
Coal: Bonn saddling the economy with new burdens
International Nuclear Information System (INIS)
The prospects of an energy consensus between the p[arties have faded away. The Social Democrats and Christian Democrats are jeopardizing the possible compromise between coal and nuclear energy. Now there are efforts to concoct a new energy tax. The economy must prepare to cope with higher costs for nuclear energy and coal. (HP)
27 CFR 9.203 - Saddle Rock-Malibu.
2010-04-01
... Conejo land grant, section 3, T1S/R19W; then (3) Proceed straight east-southeast along the El Conejo land... mile along the El Conejo land grant boundary line to its second intersection with the...
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. ...
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
La distribución global del ingreso. De la caída del muro de Berlín a la gran recesión
Christoph Lakner; Branko Milanovic
2015-01-01
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 much...
A representación dos espazos suburbanos no cinema ficcional europeo tras a caída do Muro de Berlín
Paradelo Núñez, Martín
2015-01-01
Trázase no presente traballo unha panorámica das formas de representación que o cinema europeo desenvolveu para se enfrontar á filmación dos espazos suburbais das cidades europeas. Pártese dunha definición destas estratexias de representación fílmica desde a definición dos diferentes modos de representación cinematográficos e faise fincapé na importancia do realismo e da capacidade de transmisión dunha visión crítica sobre a cidade como colector social e as dinámicas socio-econ...
La distribución global del ingreso. De la caída del muro de Berlín a la gran recesión
Directory of Open Access Journals (Sweden)
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.
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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.
Emil Rekanović; Ivana Potočnik; Miloš Stepanović; Svetlana Milijašević; Biljana Todorović
2008-01-01
The efficacy of new fungicide mixtures in controlling Plasmopara viticola in grapevine was evaluated in field trials. The efficacies of Profiler (fluopicolide + fosetyl-Al) and the standard fungicide Mikal Flash (fosetyl-Al + folpet) were tested at Radmilovac and Slankamenački Vinogradi in 2006 and 2007. Both tested fungicides exhibited high efficacy in controlling grape downy mildew. There were no significant differencies in the efficacies of Profiler(96.1-99.7%) and Mikal Flash (94.9-99.2%)...
Rekanović Emil; Potočnik Ivana; Stepanović Miloš; Milijašević Svetlana; Todorović Biljana
2008-01-01
The efficacy of new fungicide mixtures in controlling Plasmopara viticola in grapevine was evaluated in field trials. The efficacies of Profiler (fluopicolide + fosetyl-Al) and the standard fungicide Mikal Flash (fosetyl-Al + folpet) were tested at Radmilovac and Slankamenacki Vinogradi in 2006 and 2007. Both tested fungicides exhibited high efficacy in controlling grape downy mildew. There were no significant differencies in the efficacies of Profiler (96.1-99.7%) and Mikal Flash (94.9-99.2%...
Directory of Open Access Journals (Sweden)
Emil Rekanović
2008-01-01
Full Text Available The efficacy of new fungicide mixtures in controlling Plasmopara viticola in grapevine was evaluated in field trials. The efficacies of Profiler (fluopicolide + fosetyl-Al and the standard fungicide Mikal Flash (fosetyl-Al + folpet were tested at Radmilovac and Slankamenački Vinogradi in 2006 and 2007. Both tested fungicides exhibited high efficacy in controlling grape downy mildew. There were no significant differencies in the efficacies of Profiler(96.1-99.7% and Mikal Flash (94.9-99.2%. Our experiments showed that the investigated fungicide mixture fluopicolide + fosetyl-Al is highly effective against P. viticola, even when it it is applied at long intervals and under high disease pressure.
Axelsson, O.; Blaheta, R. (Radim); Byczanski, P. (Petr)
2012-01-01
Poroelastic models arise in reservoir modeling and many other important applications. Under certain assumptions, they involve a time-dependent coupled system consisting of Navier–Lamé equations for the displacements, Darcy’s flow equation for the fluid velocity and a divergence constraint equation. Stability for infinite time of the continuous problem and, second and third order accurate, time discretized equations are shown. Methods to handle the lack of regularity at initial times a...
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.
Textual Sources Fuzhou Saddle Wall%福州马鞍墙渊源考辨
Institute of Scientific and Technical Information of China (English)
汪晓东
2012-01-01
福州马鞍墙是封火墙的一种类型。关于它的渊源考证,一些专家学者认为马鞍墙源自徽州的马头墙,但这种观点有许多可疑之处。通过福州马鞍墙的形式、功能、材料、所处的地理环境、客家迁徙史以及宗教信仰等方面来说明福州马鞍墙可能更早于徽州的马头墙。马鞍墙是福州地区传统民居建筑的一大特色,探讨它的渊源对我们研究中国传统民居建筑具有重要的意义。
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.
Transition in pipe flow: the saddle structure on the boundary of turbulence
Duguet, Yohann; Kerswell, Rich R
2007-01-01
The laminar-turbulent boundary S is the set separating initial conditions which immediately relaminarise from those which lead to turbulence. Phase space trajectories on this hypersurface in cylindrical pipe flow are chaotic and show recurring evidence of coherent structures. A general numerical technique is developed for recognising near-visits to these structures and then for identifying the exact coherent solutions themselves. Numerical evidence is presented which suggests that trajectories on S are organised around only a few travelling waves and their heteroclinic connections. If the flow is suitably constrained to a subspace with a discrete rotational symmetry, it is possible to find locally-attracting travelling waves embedded within S. Using this technique, 5 new travelling wave branches were found.
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.
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...
Exotic Homoclinic Surface of a Saddle-Node Limit Cycle in a Leech Neuron Model
Institute of Scientific and Technical Information of China (English)
YOOER Chi-Feng; WEI Fang; XU Jian-Xue; ZHANG Xin-Hua
2011-01-01
We carry out numerical and theoretical investigations on the global unstable invariant set(manifold) of a saddlenode limit cycle in a leech heart interneuron model. The corresponding global bifurcation is accompanied by an explosion of secondary bifurcations of limit cycles and the emergence of loop-shaped bifurcation structures.The dynamical behaviors of the trajectories of the invariant set are very complicated and can only be partially explained by existing theories.
Alexy, Robert
2000-01-01
Traducción de: Der Beschluß des Bundesverfassungsgerichts zu den Tötungen an der innerdeutschen Grenze vom 24. Oktober 1996, Hamburg, Joachim Jungius-Gesellschaft der Wissenschaften/Vandenhoeck & Ruprecht, 1997 (Berichte aus den Sitzungen der Joachim Jungius-Gesellschaft der Wissenschaften e.V., Jahrgang 15, 1997, Heft 3). Traducción: A. Daniel Oliver-Lalana.
Luciano, Pietro; Lentini, Andrea; Prota, Romolo; Verdinelli, Marcello; Deiana, Pietrino
1993-01-01
The study was carried out in a North Sardinian cork oak forest in 1992. To control the gypsy moth population three commercial preparations of B. thuringiensis subsp. kurstaki were applied by helicopter: Activator THK and Bactospeine at low volume and Foray 48B at ultra low volume, when 80-90% of the gypsy moth larvae were in 1st and 2nd instars. At 14d after treatment, Activator (applied at 5 l/ha) did not cause significant population reductions, while Bactospeine (applied at 32 ...
ŞİŞMAN, Reyhan; DAYI, Burak; USLU, Mustafa Özay; YALÇIN, Muhamet
2015-01-01
In today's dental practice for anterior restorations patients have to wait for more conservative, aestaetic procedures also as quickly and economic as possible. It is described the prosthetic treatment of periodontally destroyed two anterior teeth after extraction at this study. After radiographic, periodontal and prosthetic assessments it was decided to use extracted tooth as pontic with glass fiber to be drawn in the bridge. The clinical situation has been observed successfully after 3 mont...
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...
バーリ＆ミーンズの株式会社論―巨大株式会社規制の理論的根拠をめぐって―
柴田, 努; Shibata, Tsutomu
2011-01-01
This paper examines in detail The Modern Corporation and Private Property (1932) by AdolfBerle and Gardiner Means, to show clearly that the essence of their theory concerned thepoint of how to justify social regulation of massive joint-stock corporations.Traditionally, the Berle and Means thesis often has been subjected to the criticism thateven under the “separation of ownership and control” that they discuss management does notact with neutrality. However, consideration of Berle and Means’...
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.
Institute of Scientific and Technical Information of China (English)
YEYANQIAN
1997-01-01
As a continuation of [1], the author studies the limit cycle bifurcation around the focus S1 other than O(0, 0) for the system (1) as δ varies. A conjecture on the non-existence of limit cycles around S1, and another one on the non-coexistence of limit cycles wound both O and S1 are given, together with some numerical examples.
德国骑乘马线粒体DNA的限制性酶分析%Restriction Endonuclease Analysis of Mitochondrial DNA of German Saddle-Horse
Institute of Scientific and Technical Information of China (English)
陈宏; Leibe,F
1999-01-01
通过5种限制性内切酶获得了13匹德国骑乘马线粒体DNA(mtDNA)的切割图谱.结果发现,限制性消化产生了1(EcoRⅠ),3(BglⅡ),4(BamHⅠ)或5个(HindⅢ和BamHⅠ)限制性片断,并确定了所有片断的分子大小.mtDNA总的大小平均为(16.48±0.10) kb.除BamHⅠ外,mtDNA的限制性切点对于所有的个体是完全一致的.用BamHⅠ检测到mtDNA的多态性,通过带谱分析推断,德国骑乘马的B型mtDNA是由A型mtDNA通过突变产生1个新的切割位点进化而来.
Hsu, Pen-Yuan; Notsu, Hirofumi; Yoneda, Tsuyoshi
2015-01-01
As one of the violent flow, tornadoes occur in many place of the world. In order to reduce human losses and material damage caused by tornadoes, there are many research methods. One of the effective methods is numerical simulations such as the work in a recent article Ishihara et al. (2011). The swirling structure is significant both in mathematical analysis and the numerical simulations of tornado. In this paper, we try to clarify the swirling structure. More precisely, we do numerical compu...
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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.
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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”
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
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
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)
肖质江; 王炎; 郑彩霞
2010-01-01
通过对一座部分斜拉桥主塔鞍座处局部应力分布的有限元计算分析,说明部分斜拉桥主塔鞍座处局部应力的分布特征.依据鞍座处局部应力影响范围很小的特点,提出设置螺旋筋和索孔端部镶嵌预埋钢板的局部设计补强措施,避免在索鞍下出现危及结构耐久性的有害裂缝.
Institute of Scientific and Technical Information of China (English)
吴新智
2008-01-01
本文以周口店、南京、Atapuerca SH5、Petralona、Arago、Bodo、Kabwe的中更新世人类化石举例显示,在类似的环境中鼻梁高耸的程度可以不同,小同凉热可以有相似高耸的鼻梁,从而对南京直立人的高鼻梁不是由于对寒冷气候的适应的论点提出补充论证.在这样的情况下,白然应该考虑南京直立人鼻梁高耸的原因在于遗传的冈素.本文试图探讨南京高耸鼻梁可能的基因来源,首先论证在中国化石人类中罕见高耸的鼻梁,更没有比南京更早的高耸鼻梁,而非洲和欧洲中更新世多见高耸鼻梁,这种状态在欧洲延续至今,而且非洲已经发现60万年前的比南京早的高耸鼻梁.最后讨论南京直立人的时代和与非洲、欧洲相距遥远的地理位置都不能否定本文的推论.
Institute of Scientific and Technical Information of China (English)
吴新智; 尚虹
2007-01-01
有人质疑南京直立人的高耸鼻梁的成因,认为高鼻梁是对寒冷和干燥气候的适应,有两篇论文被引用来作为支持.本文指出那两篇论文讨论的是鼻高,鼻宽与纬度的关系,结论是纬度较高者鼻宽较小,并没有论证高鼻梁是对寒冷和干燥气候的适应.本文还援引其他不同纬度地区人群反映鼻的不同部分向前方突出程度的资料,指出目前很难看出鼻的突出程度与气候如何相关.这些资料和寒带因纽特人的扁鼻梁与热带的Bodo化石头骨的高鼻梁的对比以及南京直立人1号头骨所在的堆积物反映温带或亚热带气候,都反对或至少是不支持高耸鼻梁是适应寒冷和干燥气候结果的观点.目前也还没有证据表明南京直立人的高鼻梁可以在东亚的人类谱系上溯源到某些曾经由于对寒冷气候的适应而具有高鼻梁的古人类.
An altered cast procedure to improve tissue support for removable partial denture
Directory of Open Access Journals (Sweden)
Chandrashekar Sajjan
2010-01-01
In the laboratory, the free-end saddle areas on the master cast are sectioned off. The denture is then positioned on the model and the new saddle areas are poured. The resulting model represents the free-end saddle areas under conditions, which mimic functional load. Denture construction then continues as normal. The distribution of loading of the free-end saddles is improved and denture is more stable.
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
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
La vigencia de los planteamientos estéticos y musicales de Hanns Eisler
Notario Ruiz, Antonio
2009-01-01
Entre el 31 de octubre y el 2 de noviembre de 2008, en Berlín, se reunieron especialistas en la producción musical y teórica de Hanns Eisler en un simposio internacional centrado en su teoría y praxis de música para el cine.
Art Student Perceptions of the Role of Community Service in Israeli Teacher Education
Bachar, Pnina; Ofri, Vinnie
2009-01-01
The purpose of this research was to understand how student art teachers perceive the contribution to their training of community service in various frameworks, such as a prison and a drug rehabilitation center. The research was conducted in 2006-2007 in the School of Art at Beit Berl College, Israel, in two stages. In the first stage, six…
What is Happening to Corporations and What of Their Future?
DEFF Research Database (Denmark)
Thompson, Grahame
2012-01-01
. 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...
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
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
The nomination of directors under U.S. and German law
Donald, David C.
2003-01-01
Revised Draft: January 2005, First Draft: December 8, 2004 The picture of dispersed, isolated and uninterested shareholders so graphically drawn by Adolf Berle and Gardiner Means in 19321 is for the most part no longer accurate in today's market, although their famous observations on the separation of control and ownership of public corporations remain true.
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...
Three oilseed sunflower (Helianthus annuus L.) genetic stocks, HA 458, HA 459, and HA 460 have been released which are resistant to downy mildew (caused by Plasmopara halstedii (Farl.) Berl. & De Toni) and possess a high-oleic fatty acid profile (oleic acid > 800 g kg-1) in the seed oil. These genet...
Renneboog, L.D.R.; Liang, H.; Ferrell, A.
2014-01-01
In the corporate finance tradition starting with Berle & Means (1923), corporations should generally be run so as to maximize shareholder value. The agency view of corporate social responsibility (CSR) generally considers CSR as a managerial agency problem and a waste of corporate resources, since c
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
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.
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.
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).
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?
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)
李娟娟
2009-01-01
对13MnNiMoNbR+00Cr17Ni14Mo2复合钢板与20MnMoNbⅣ+00Cr17Ni14Mo2锻件进行了焊接性分析.针对大直径厚壁马鞍形对接焊缝结构特点,采用合理的施工工艺,并通过对焊接过程中预热温度的控制、焊后消氢及焊后热处理等工艺的合理调整,有效防止了冷裂纹的产生,保证了产品焊接质量.
A principios de los años 90 ciudad europea era un insulto. Entrevista a Hans Stimmann
Garcia Hermida, Alejandro; Rivera Gamez, David; Murillo, Blanca; Stimmann, Hans
2014-01-01
Hans Stimmann (Lübeck, 1941) será recordado en la historia del urbanismo como el creador de la estructura y buena parte de la imagen del llamado ?Nuevo Berlín?, es decir, del Berlín central reconstruido posterior a la caída del Muro, en lo que constituye la intervención urbana más importante en Europa desde la Segunda Postguerra Mundial. Además, Stimmann se ha convertido en un símbolo para todos aquéllos teóricos y arquitectos que buscan corregir el paradójico urbanismo anti-urbano que nos ha...
MOND habitats within the solar system
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....
Monitoring to reduce agency costs: Examining the behavior of independent and non-independent boards
Anand, Anita; Milne, Frank; Purda, Lynnette
2010-01-01
Berle and Means's analysis of the corporation - in particular, their view that those in control are not the owners of the corporation - raises questions about actions that corporations take to counter concerns regarding management's influence. What mechanisms, if any, do corporations implement to balance the distribution of power in the corporation? To address this question, we analyze boards of directors' propensity to voluntarily adopt recommended corporate governance practices. Because boa...
Corporate Ownership Around the World
Rafael La Porta; Florencio Lopez-de-Silane; Andrei Shleifer
1998-01-01
We present data on ownership structures of large corporations in 27 wealthy economies, making an effort to identify ultimate controlling shareholders of these firms. We find that, except in economies with very good shareholder protection, relatively few of these firms are widely-held, in contrast to the Berle and Means image of ownership of the modern corporation. Rather, these firms are typically controlled by families or the State. Equity control by financial institutions or other widely-he...
Equity Linked Compensation as a Risk Management Tool in the Good Governance of U.S. Investment Banks
Nikolas Venema
2013-01-01
Due to the separation between ownership and management and, in the absence of at least a single major shareholder, executives of publicly traded companies have almost complete power and discretion in management to pursue projects that benefit themselves personally but which may not optimize shareholder interest (Berle and Means, 1932). The focus of this paper is on the structure of chief executive officer (CEO) and chief financial officer (CFO) compensation packages of publicly traded fina...
Renneboog, L.D.R.; Liang, H; Ferrell, A.
2014-01-01
In the corporate finance tradition starting with Berle & Means (1923), corporations should generally be run so as to maximize shareholder value. The agency view of corporate social responsibility (CSR) generally considers CSR as a managerial agency problem and a waste of corporate resources, since corporate insiders do good with other people’s money. We evaluate this agency view using large-scale datasets with global coverage (59 countries) on firm-level corporate engagement and compliance wi...
Corporate Ownership Structure and Firm Performance: Evidence from Greek Firms
Panayotis Kapopoulos; Sophia Lazaretou
2006-01-01
The Berle-Means thesis (1932) implies that diffuse ownership adversely affects firm performance. This paper tries to investigate whether there is strong evidence to support the notion that variations across firms in observed ownership structures result in systematic variations in observed firm performance. We test this hypothesis by assessing the impact of the structure of ownership on corporate performance, measured by profitability, using data for 175 Greek listed firms. Following Demsetz a...
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.
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.
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
On the structure of phase synchronized chaos
DEFF Research Database (Denmark)
Mosekilde, Erik; Zhusubaliyev, Zhanybai T.; Laugesen, Jakob L.;
2013-01-01
It is well-known that the transition to chaotic phase synchronization for a periodically driven chaotic oscillator of spiral type involves a dense set of saddle-node bifurcations. However, the way of formation and precise organization of these saddle node bifurcation curves have only recently been...
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.
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.
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...
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.
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.
A Note on the Estimation of Semiparametric Two-Sample Density Ratio Models
Institute of Scientific and Technical Information of China (English)
Gang YU; Wei GAO; Ningzhong SHI
2012-01-01
In this paper,a semiparametric two-sample density ratio model is considered and the empirical likelihood method is applied to obtain the parameters estimation.A commonly occurring problem in computing is that the empirical likelihood function may be a concaveconvex function.Here a simple Lagrange saddle point algorithm is presented for computing the saddle point of the empirical likelihood function when the Lagrange multiplier has no explicit solution.So we can obtain the maximum empirical likelihood estimation (MELE) of parameters.Monte Carlo simulations are presented to illustrate the Lagrange saddle point algorithm.
The potential energy landscape in the Lennard-Jones binary mixture model
International Nuclear Information System (INIS)
The potential energy landscape in the Kob-Andersen Lennard-Jones binary mixture model has been studied carefully from the liquid down to the supercooled regime, from T = 2 down to 0.46. One thousand independent configurations along the time evolution locus have been examined at each temperature investigated. From the starting configuration, we searched for the nearest saddle (or quasi-saddle) and minimum of the potential energy. The vibrational densities of states for the starting and the two derived configurations have been evaluated. Besides the number of negative eigenvalues of the saddles other quantities show some signature of the approach of the dynamical arrest temperature
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.
Dinamarca, Hernán
2012-01-01
Recién publicado en Alemania, este libro nació de una colaboración entre el Instituto Ibero-Americano de Berlín y el Instituto de Romanística de la Universidad Justus Liebig de Giessen. Se trata de una compilación de 15 ensayos editados por la Profesora - Dra. Verena Dolle. Lo primero que llama la atención a un lector no especializado, como es mi caso, es el uso del concepto Múltiples Identidades. A priori tendemos a pensar que si se trata de literatura judeo-latinoamericana, simplemente esa ...
Los efectos de la "americanización" de las campañas electorales del mundo
Rodríguez-Andrés, R. (Roberto)
2012-01-01
Estados Unidos ejerce un papel de “laboratorio social” en el que se ensayan tendencias culturales, sociales y políticas que acaban implantándose con el tiempo en el resto del mundo. Este proceso de “americanización” se ha acelerado desde la caída del Muro de Berlín y el desmoronamiento del comunismo, que ha reforzado el protagonismo de Estados Unidos como primera potencia del mundo y también como espejo en el que, voluntaria o involuntariamente, se acaban reflejando otros muchos países, inclu...
Mario López Martínez
2013-01-01
Este artículo pretende analizar cómo se han producido cambios importantes en el mundo tras la caída del Muro de Berlín. Se ha acentuado la idea de un solo mundo, un solo sistema económico mundial, una sola humanidad. Se han producido importantes transformaciones: pérdida de legitimidad y de soberanía de los estados-nación, expansión del proceso de globalización, se ha extendido la idea de crisis civilizatoria, se han incrementado nuevas guerras asociadas a geopolíticas neoimperialistas, etc. ...
Carlos Ortiz de Landázuri
2011-01-01
Se analizan cuatro interpretaciones actuales de la caída del muro de Berlín en 1989, en las que se reflexiona sobre el doble uso que Francis Fukuyama y Erik J. Hobsbawm hicieron de esta fecha de corte, según la concibieran como el fin de la historia en sentido liberal o el término de un siglo corto donde tuvo lugar la autodisolución del comunismo. Pero simultáneamente también se reconstruye el cuádruple efecto perverso que incluso hoy día siguen teniendo las distintas estrategias seguidas ent...
Canevacci, Massimo
1998-01-01
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 «biene...
La Agenda del desarrollo de Barcelona, una superación (parcial) del Consenso de Washington
Estefanía, Joaquín, 1951-
2005-01-01
Con la caída del muro de Berlín y la autodestrucción del socialismo real, como sistema alternativo, se acelera el actual proceso de globalización económica. Las fuerzas conservadoras producen inmediatamente dos documentos que cartografían su proceso de actuación: el fin de la historia de Fukuyama, como mapa geopolítico, y el Consenso de Washington, como analogía económica del fin de la historia. Durante más de una década, el pensamiento neoliberal que manifiestan estos...
Juan Manuel Fernández Chico
2011-01-01
Este artículo intenta hilas tres momentos claves en la historia de la geopolítica de la seguridad: la caída del muro de Berlín, el ataque del once de septiembre de 2001 al World Trade Center y las recientes filtraciones del Departamento de Estado por parte de la organización Wikileaks, para trazar cómo el proyecto de protección global a través del miedo, encabezado por Estados Unidos, legitima sus acciones geopolíticas, ahora impactando también en la Internet, justificándolo por medio de la a...
Cruset, María Eugenia
2009-01-01
Con la caída del Muro de Berlín en 1989 se cierra un ciclo que comenzó alrededor de cuarenta años atrás con el fin de la Segunda Guerra Mundial. Sin embargo, este ciclo debe ser estudiado como uno de larga duración que empezó a gestarse a mediados del siglo XIX cuando Alemania se unifica. Este ciclo que se cierra abre, a su vez, uno nuevo, donde el país se convierte en motor de la Unión Europea y potencia económica mundial.
Sánchez-Seco López, Alejandro
2014-01-01
En el contexto de una obra mucho más amplia, que propone como único sistema plenamente legítimo aquél cuyo cuerpo político viene constituido por la totalidad de habitantes del planeta, es conveniente reflexionar acerca del sistema capitalista y su reforma. Parece obvio que, desde la caída del muro de Berlín, el mundo no ha sabido vivir sin el capitalismo y que su óbito no parece cercano. Su necesidad de reforma sí se ha mostrado necesaria, y más en un contexto de globalización creciente. La r...
Escenarios sobre el orden internacional
Luis Dallanegra Pedraza
2012-01-01
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 motore...
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...
C. El segle de les grans barbàries
Nadal Gaya, Carlos, 1923-2010
2013-01-01
Conté: Un día cualquiera de agosto; Hace diez años, la URSS…; Termina una vergüenza de Europa; Del nacional arabismo al islamismo; El Imperio vuelve a tener enemigo; La caída del tirano; La Normandía a Iraq; Derrota y rehabilitación de Europa; La gran metáfora de la plaza Roja; Los derechos humanos y la realidad; El siglo de la guerra total (1); El siglo de la guerra total (y 2); Memoria del muro de Berlín
La casa con patio en Mies van der Rohe
Altés Bustelo, José
2013-01-01
Una revisión del tema Casa con Patio, con especial atención a los planteamientos desarrollados por Mies van der Rohe durante sus últimos años en Berlín, a propósito del conocido dibujo denominado “Casa con tres patios”. Se explora su pensamiento arquitectónico a partir de los datos historiográficos de su trayectoria, más los que se pueden deducir del análisis de los dibujos y croquis previos del arquitecto. El conjunto de proyectos en que aparece el tema es muy amplio durante ese tiempo y los...
Ramírez Blanco, Julia
2015-01-01
Este trabajo estudia la centralidad de los discursos utópicos en Europa occidental después de la caída del Muro de Berlín, dentro de los movimientos sociales extraparlamentarios y el arte. Considerando la importancia de distinguir entre las diferentes esferas analizadas, la presente Tesis Doctoral ha adoptado una estructura tripartita. En una gradación que va in crescendo, la primera parte comienza con el estudio de la creatividad utópica de algunos movimientos sociales entre 1989 y 2003 (cap...
Ambos, Kai
2009-01-01
Alemania tuvo que superar la transición1 de un sistema totalitario a un sistema democrático en dos oportunidades durante el siglo pasado: por una parte durante la lenta elaboración de las injusticias e ilegalidades propias del nacionalsocialismo desde el fin de la Segunda Guerra Mundial (8 de mayo de 1945), por otra parte durante la elaboración de la criminalidad, propia del sistema de la República Democrática Alemana (RDA) desde la caída del muro de Berlín (9 de noviembre de 1989...
Villacañas, José Luis
2013-01-01
El ensayo se plantea a partir de Max Weber y, de entrada, aborda un síntoma que muestra hasta qué punto la previsión ilustrada de la historia nos acompañó hasta hace poco. Para ello se utiliza el asunto del muro de Berlín y su caída. Un segundo apartado argumenta que sobre esta base de estabilidad ilustrada se abrió paso, como su contrapunto de optimismo, un sentido de indisponibilidad de la historia, de vigencia de lo no previsible en ella, de lo que no está sometido al control humano. Estos...
LA CASA CON PATIO EN MIES VAN DER ROHE / House with patio from Mies van der Rohe
José Altés Bustelo
2013-01-01
RESUMEN Una revisión del tema Casa con Patio, con especial atención a los planteamientos desarrollados por Mies van der Rohe durante sus últimos años en Berlín, a propósito del conocido dibujo denominado “Casa con tres patios”. Se explora su pensamiento arquitectónico a partir de los datos historiográficos de su trayectoria, más los que se pueden deducir del análisis de los dibujos y croquis previos del arquitecto. El conjunto de proyectos en que aparece el tema es muy amplio durante ese tiem...
Burchardt, Hans-Jürgen
1999-01-01
El artículo trata de explorar los factores que permiten al sistema político de Cuba una todavía estabilidad sorprendente, a una década después de la caída del muro de Berlín. Al principio se introducen los elementos estructurales exógenos y endógenos del socialismo cubano y presenta los antecedentes de la crisis. Posteriormente se documenta grosso modo el proceso de reformas y las medidas adoptadas en la Isla. El siguiente análisis demuestra que la sociedad cubana se encuentra en un proceso d...
Frybes, Marcin
2015-01-01
Las sociedades de Europa Central (Polonia, Hungría, República Checa y Eslovaquia) viven desde el derrumbamiento del sistema comunista, toda una serie de transformaciones políticas, sociales y económicas. Calificadas por muchos de “transiciones a la democracia y a la economía de mercado”, estas transformaciones resultaron ser, cinco años después de la caída del muro de Berlín, de naturaleza notablemente más compleja. La “transición” no se puede concebir como una simple “imitación” del modelo d...
Rabazo Martín, Marta
2013-01-01
Partiendo del estudio del vacío del muro de Berlín en el Laboratorio de Paisaje como infraestructura lineal y espacio anómalo, se pretende profundizar la investigación de los vacíos generados por las infraestructuras lineales que atraviesan nuestras ciudades, espacios marginales, olvidados o apartados de la trama urbana pero llenos de identidad y significado donde se pueden generar nuevas oportunidades para el espacio público. A través de un estudio de casos se intentará analizar la ...
“How long is now?”: extravíos berlineses (1993-2015)
Casamayor Cisneros, Odette
2015-01-01
Resumen: Tejiendo ficción y narrativa autobiográfica vuelco en este texto las experiencias de una cubana que en la década del noventa pudo al fin viajar al extranjero y conocer otras realidades. Las controvertidas emociones que desata en la protagonista de veinte años vivir junto a su amante los primeros tiempos de la reunificación entre el Este y el Oeste, tras la Caída del Muro de Berlín, es lo que intento trasmitir con este texto. Se enfrentan aquí, a través de la sutileza de las emociones...
Mediateca pública de nuevas tecnologías multimedia. Warschauer Brücke. Berlin
López Barba, Paula
2009-01-01
Estación Warschauer Straße: +50.000viajeros/día Elegí este lugar en la antigua zona este de Berlín para mi proyecto final de carrera porque me parecía un territorio complejo, desordenado, pero con mucho potencial. Totalmente segmentado por las infraestructuras, los restos del muro y el río. Actualmente, la estación de Warschauerstraße tiene un transbordo entre líneas de metro muy desestructurado. Propongo trasladar la actual estación de U-bahn [metro] para mejorar el transbordo con el...
Miguel Martínez
2005-01-01
El proceso de integración europeo por momentos ha avanzado a un ritmo muy rápido y en otros lo ha hecho lentamente o se ha estancado. Los acontecimientos internacionales y la nueva configuración del sistema internacional han obligado a la UE a empezar a jugar un papel importante en la escena internacional fuera del arco de influencia de Estados Unidos, pues a partir de la caída del Muro de Berlín hay intereses europeos que no coinciden con los norteamericanos. Es aquí donde ya es cada vez más...
Escenarios para los medios de comunicación en la era post-Fidel Castro
Pecero, Iris
2007-01-01
En el contexto de la sucesión de poder que tiene lugar actualmente en Cuba, pueden dibujarse algunos escenarios para los medios de comunicación de la isla en una era post-Fidel. La historia de los medios de comunicación en Cuba durante el período revolucionario, las experiencias de la URSS y los restantes países socialistas de Europa del Este, luego de la caída del Muro de Berlín, y las particulares circunstancias de China son algunos de los elementos a tener en cuenta. ...
Sociedad civil y capital social
José Fernández Santillán
2009-01-01
Este documento aborda el tema de la democracia desde una perspectiva opuesta al llamado neoinstitucionalismo; es decir, se orienta a analizar los procesos de democratización desde la base de la sociedad civil y, en es pe cial, desde lo que se conoce como el cap i tal so cial. Desde mediados de la década de 1980, el tema de la democracia desde la perspectiva de la sociedad civil fue cobrando cada vez mayor relevancia. Esta tendencia se vio reforzada por la caída del Muro de Berlín el 9 de nov...
A LA LUZ DE LAS CÚPULAS. RESTAURACIÓN DEL REICHSTAG DE BERLÍN (1992–1999). FOSTER & PARTNERS
Manuel Trillo de Leyva
2010-01-01
RESUMEN Durante el curso académico 2000-2001, los profesores del Aula Taller F realizaron un seminario dedicado a la arquitectura contemporánea de Berlín. Además de las conferencias impartidas se visitaron las obras que habían sido analizadas en el seminario. Este artículo, escrito en marzo de 2001, añade una reflexión final, escrita en marzo del año 2002, consecuencia de esa visita conjunta que, profesores y estudiantes, realizaron al Reigchstag.Con el cambio de milenio, las principales ciud...
A.A. Maldonado; M. Küntscher; Sillero, A.
2012-01-01
Nuestro objetivo es el cálculo de la carga eléctrica en plasma de grandes quemados mediante un programa informático enfocado a predecir la mortalidad del paciente. Partimos del software informático PICAL (de confección propia) con el fin de calcular la carga plasmática y la influencia de iones y proteínas, aplicado a 143 pacientes en la Unidad de Grandes Quemados del Hospital Unfallkrankenhaus de Berlín (Alemania). Realizados los cálculos anteriores, efectuamos un estudio estadístico para def...
Statik und dynamik der schalen
Carrizosa Valenzuela, Julio
2010-01-01
"Se refiere este libro a uno de los problemas más interesantes en la actualidad: el cálculo de estructuras constituídas por láminas curvadas capaces, principalmente por su forma, de cubrir luces bastante grandes, a pesar de presentar espesores relativamente muy pequeños en relación con dichas luces".WILHELM FLÜGGE: Statik und Dynamik der Schalen ("Julius Springer". Berlín, 1934). Photo-Lithoprint. Reproduction, published and distributed in the Public Interest by authority of the Alien Propert...
The Revitalisation of NATO and European Security
Nicholas Williams
1997-01-01
Los esfuerzos para construir una Identidad Europea de Seguridad y Defensa (IESD)recibieron un impulso importante tras la experiencia yugoslava, que revitalizó la OTAN y mostró a los países europeos sus limitaciones. Estas se evidenciaron especialmente tras la decisión, adoptada en 1996 en Berlín por los ministros de asuntos exteriores delos países de la Alianza, de construir la IESD dentro del marco OTAN. Williams revisa los futuros retos de la IESD a la luz de la ampliación de la OTAN, el fo...
City branding y posicionamiento online de capitales europeas en el sector turístico
Fernández López, Alejandra Carmen
2015-01-01
El principal objetivo de esta tesis doctoral es el análisis y evaluación del city branding en cinco capitales europeas (Londres, París, Berlín, Roma y Madrid) desde la perspectiva de los visitantes, estudiando las principales diferencias existentes según la forma de buscar información, online u offline; así como el estudio del posicionamiento online que estas ciudades tienen en Internet. En concreto, desde una perspectiva teórica, se realiza un análisis del sector turístico, estudiando al...
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 ...
Ramos Núñez, Francisco
2013-01-01
El centenario de la première de la Consagración de la primavera de Stravinsky se conmemoró el pasado mayo y habiéndose celebrado el estreno del Pierrot Lunaire de Arnold Schönberg en Berlín en octubre de 1912, sólo unos meses antes. Ambas obras maestras continúan ejerciendo su influencia hoy en día. Sin embargo, mientras la obra de Stravinsky se mantiene en el repertorio usualmente interpretado en los conciertos, la pieza de Schönberg –generalmente considerada piedra angular de la...
Does prism width from the shell prismatic layer have a random distribution?
Verrecchia, Eric P.; Vancolen, Séverine
2009-01-01
A study of the distribution of the prism width inside the prismatic layer of Unio tumidus (Philipsson 1788, Diss Hist-Nat, Berling, Lundæ) from Lake Neuchâtel, Switzerland, has been conducted in order to determine whether or not this distribution is random. Measurements of 954 to 1,343 prism widths (depending on shell sample) have been made using a scanning electron microscope in backscattered electron mode. A white noise test has been applied to the distribution of prism sizes (i.e. width). ...
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.
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...
49 CFR 179.200-14 - Expansion capacity.
2010-10-01
... bottom of any vent pipe projecting inside of dome, except that when a pressure relief device is applied... reinforced by a seamless saddle plate equal to or greater than shell in thickness and butt welded to...
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.
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.
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.
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...
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.
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.
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.
A Genealogy of Convex Solids Via Local and Global Bifurcations of Gradient Vector Fields
Domokos, Gábor; Holmes, Philip; Lángi, Zsolt
2016-06-01
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.
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.
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...
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...
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.......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....
The use of nasal markers for monitoring mallard populations
Fabião, António; Rodrigues, David; Figueiredo, Maria
2001-01-01
We discuss the advantages and limitations of alphanumeric-coded nasal markers used for monitoring resident mallard populations. We tested two designs of nasal saddles, various colours, PVC tape of 2 thicknesses and ribber tape. The rctangular nasal saddle could disturb birds during feeding, so we changed it to a more anatomical design. The use of alphanumeric coded nasal markers was an efficient method for marking mallards in small wetlands with good visibility and for relatively short periods.
Strong-field approximation for harmonic generation in diatomic molecules
Chirila, Ciprian C.; Lein, Manfred
2005-01-01
The generation of high-order harmonics in diatomic molecules is investigated within the framework of the strong-field approximation. We show that the conventional saddle-point approximation is not suitable for large internuclear distances. An adapted saddle-point method that takes into account the molecular structure is presented. We analyze the predictions for the harmonic-generation spectra in both the velocity and the length gauge. At large internuclear separations, we compare the resultin...
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.
Delay-induced multistability near a global bifurcation
Hizanidis, J.; Aust, R.; Schoell, E.
2007-01-01
We study the effect of a time-delayed feedback within a generic model for a saddle-node bifurcation on a limit cycle. Without delay the only attractor below this global bifurcation is a stable node. Delay renders the phase space infinite-dimensional and creates multistability of periodic orbits and the fixed point. Homoclinic bifurcations, period-doubling and saddle-node bifurcations of limit cycles are found in accordance with Shilnikov's theorems.
Random Matrix Theory by the Supersymmetry Method Beyond the Sigma-Model
Lucic, Vladan
1996-01-01
The leading correction to the smoothed connected energy density-density correlation function is obtained for the large energy difference, within the context of the Gaussian Random Matrix Theory. In order to achieve this result, the supersymmetry method is extended beyond the sigma-model, to include small quadratic fluctuations around the saddle point. Special care is taken to avoid the potential divergence arising from the unbounded nature of the saddle point. Also, in the small energy differ...
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...
Vector fields in holographic cosmology
Hartle, James B.; Hawking, S. W.; Hertog, Thomas
2013-01-01
We extend the holographic formulation of the semiclassical no-boundary wave function (NBWF) to models with Maxwell vector fields. It is shown that the familiar saddle points of the NBWF have a representation in which a regular, Euclidean asymptotic AdS geometry smoothly joins onto a Lorentzian asymptotically de Sitter universe through a complex transition region. The tree level probabilities of Lorentzian histories are fully specified by the action of the AdS region of the saddle points. The ...
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.
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)
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.
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.
Effect of thermal fluctuations on hysteresis of chains of magnetite crystals
International Nuclear Information System (INIS)
Complete text of publication follows. Although magnetic hysteresis is usually modeled as a set of equilibrium curves with jumps at critical fields, jumps will always occur before the critical field is reached because of thermal fluctuations. The probability of a jump at a given field depends on the network of connections between stable states by way of saddle points. The most difficult part of modeling such connections is finding the saddle points. A new method finds all the saddle points using a special tool for finding roots of polynomial systems. All equilibrium states are found and classified as stable, saddle, or other, and a two-stage solver finds the downhill paths from each saddle point to the nearest minima. A master equation is solved to get the time dependence of the magnetic moment. This method is applied to a chain of magnetostatically interacting single-domain particles such as those in magnetotactic bacteria. If there are N particles in a chain, there are up to 2N saddle points. The number of saddle points decreases until there are at most two for particles in contact with each other. In zero field, the relaxation mode for chains of 5 or more particles is a new mode that I call the two-domain fanning mode. This mode has only a limited domain of stability and is replaced by a symmetric fanning mode in larger fields. If the critical size for the transition to superparamagnetism is expressed as the cube root of the volume, it approaches about 10 nanometers as the number of particles increases, independent of the shapes of the particles.
Directory of Open Access Journals (Sweden)
V. N. Belykh
2015-01-01
Full Text Available We consider a ﬁnite-dimensional model of phase oscillators with inertia in the case of star conﬁguration of coupling. The system of equations is reduced to a nonlinearly coupled system of pendulum equations. We prove that the transition from synchronous to asynchronous oscillations occurs via bifurcation of saddle-node equilibrium. In this connection the asynchronous regime can be partially synchronous rotations. We ﬁnd that the reverse transition from asynchronous to synchronous regime occurs via bifurcation of homoclinic orbit both of the saddle equilibrium point and of the saddle periodic orbit. In the case of homoclinic loop of the saddle point the synchrony appears only from asynchronous mode without partially synchronized rotations. In the case of the homoclinic curve of the saddle periodic orbit the system undergoes a chaotic rotation regime which results in a random return to synchrony. We establish that return transitions are hysteretic in the case of large inertia.
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...
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...
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....
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...
A Memristive Diode Bridge-Based Canonical Chua’s Circuit
Directory of Open Access Journals (Sweden)
Mo Chen
2014-12-01
Full Text Available A novel memristor circuit is presented, which is generated from the canonical Chua’s circuit by replacing the Chua’s diode with a first order memristive diode bridge. The circuit dynamical characteristics with the variations of circuit parameters are investigated both theoretically and numerically. It can be found that the circuit has three determined equilibrium points, including a zero saddle point and two nonzero saddle-foci with index 2. Specially, the circuit is non-dissipative in the neighborhood of the zero saddle point, and there exists complex nonlinear phenomena of coexisting bifurcation modes and coexisting chaotic attractors. Experimental observations are performed to verify the numerical simulation results.
Modified Newtonian dynamics habitats within the solar system
International Nuclear Information System (INIS)
MOdified Newtonian Dynamics (MOND) is an interesting alternative to the presence of dark matter in galaxies. 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 sizable oblate ellipsoid around the saddle point. We work out the MOND effects using the nonrelativistic limit of the TeVeS 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
Jiang, Yu; Baoyin, Hexi
2014-01-01
This paper studies the distribution of characteristic multipliers, the stability of orbits, periodic orbits, the structure of submanifolds, the phase diagram, bifurcations and chaotic motions in the potential field of rotating highly irregular-shaped celestial bodies. The topological structure of submanifolds for the orbits in the potential field of a rotating highly irregular-shaped celestial body(hereafter irregular body for short) is discovered that it can be classified into 34 different cases, including 6 ordinary cases, 3 collisional cases, 3 degenerate real saddle cases, 7 periodic cases, 7 period-doubling cases, 1 periodic and collisional case, 1 periodic and degenerate real saddle case, 1 period-doubling and collisional case, 1 period-doubling and degenerate real saddle case as well as 4 periodic and period-doubling cases. It is found that the different distribution of characteristic multipliers fixes the structure of submanifolds, the types of orbits, the dynamical behavior and the phase diagram of t...
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.
A New Clasp to Fix Partial Dentures
Directory of Open Access Journals (Sweden)
Saakyan М.Yu.
2012-03-01
Full Text Available A new clasp to fix small saddle prostheses was designed to improve the quality of prosthetic unilateral free-end saddle restoration. Unlike the known ones, the clasp can be adapted for clinical crowns of any height (particularly useful for low crowns as no standard elements are required to be fixed on prosthesis. Prosthesis retention is independent of the height of coronal part and the evidence of its survey line. Gentle preparation of abutment teeth allows grinding off hard tooth issues minimally. The combination of fixing elements of a single clasp provides sufficient fixation to achieve high masticatory efficiency and prosthesis spatial stabilization but at the same time only partially limits its lability in mastication. The clasp can be used in free-end saddle restoration both in maxilla and mandible, and especially in patients with periodontal diseases complicated by partial tooth loss.
CALIDAD DE VIDA ¿UN DERECHO, UNA OPORTUNIDAD?
Rina De León Herrera
2002-01-01
Acontecimientos de la última década del siglo XX como, la caída del muro de Berlín, la finalización de la Guerra Fría, el Acuerdos de Marrakesh sobre la reducción de aranceles y la regulación del comercio mundial, los avances tecnológicos en las comunicaciones, han ocasionado cambios significativos en el mundo: la transformación de la economía, la interdependencia de la población, la interrelación entre la cultura, la economía y la tecnología, la mundialización de los problemas sociales. Esto...
Elizalde, Antonio
2012-01-01
El autor de este libro plantea varias interrogantes de enorme importancia para entender la historia reciente de nuestro país. ¿Cómo explicar la modernización económica de Chile durante la dictadura militar? ¿Cómo el liberalismo económico se instaló en nuestro país antes de la caída del muro de Berlín y de las experiencias conservadoras de Ronald Reagan y Margaret Thatcher? ¿Cuáles son los fenómenos que permitieron la aceptación de este modelo neoliberal? ¿De qué manera se gestaron las elites ...
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...
Hacia una agricultura multifuncional
Gutiérrez San José, Pablo; Valero Ubierna, Constantino
2008-01-01
Es interesante ubicar las conquistas tecnológicas de estos últimos 20 años dentro de su contexto histórico y social. Resulta curioso que, para algunos la globalización tuviera como hito de inicio la caída del muro de Berlín en el año 1989 hace casi 20 años. Poco tiempo antes, 22 años, España había entrado en un nuevo entorno como el de la Unión Europea. Podemos ver como nuestro medio agrícola a lo largo de estos últimos 20 años se ha encontrado con un mercado más abierto, en libre competencia...
El Imperio después del imperialismo
Negri, Toni
2012-01-01
Dos ideas fundamentales están la base de Imperio, el libro que he escrito a cuatro manos con Michael Hardt, entre la guerra del Golfo y la de Kosovo. La primera es que no existe un mercado global (en la forma en que se habla desde la caída del Muro de Berlín, es decir, no solamente como paradigma macro-económico sino como categoría política) sin forma de estructura jurídica, y que el orden jurídico no puede existir sin un-poder que garantice su eficacia. La segunda es que el orden jurídico de...
[Otra] lección del Nikolaiviertel: it from bit?
Ruiz Sánchez, Javier
2011-01-01
La actividad urbanística en Berlín oriental antes de la caída del muro es a menudo despachada como exenta de interés. Incluso una actuación tan singular como la reconstrucción del Nikolaiviertel es a menudo ignorada, o banalizada, probablemente debido a su lenguaje neohistoricista tanto como a su conversión como foco turístico en los últimos años. Ello contrasta con la atención prestada a otras actuaciones llevadas a cabo tras la reunificación. El presente artículo reivindica esta actuación, ...
Orígenes recientes y temas clave de la educación para la ciudadanía democrática actual
C. Naval
2003-01-01
En este artículo, se indaga sobre los orígenes recientes y los temas clave de la educación para la ciudadanía democrática actual. Respecto al primer punto, se destaca la relevancia de la caída del Muro de Berlín (1989) y la crítica comunitarista al liberalismo. Además, se señalan algunos rasgos de la mentalidad postmoderna en la cultura contemporánea, especialmente las implicaciones antropológicas del liberalismo en educación. La primera parte concluye con una explicación de algunos de los pr...
Aulas sin muros: Hacia una casa común educativa
Beltrán Llavador, Fernando
2009-01-01
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 co...
El alzamiento de Pascuas de 1916
Cruset, María Eugenia
2006-01-01
Hay algunos hechos en la historia que son particularmente gráficos. Si uno piensa en la caida del Muro de Berlín en 1989, en seguida le llega a la mente el fin de los 70 años del experimento socialista soviético. Del mismo modo, si recordamos la Revuelta de Pascua de 1916 podemos visualizar el fin de siglos de dominio inglés sobre Irlanda. Y, aunque estrictamente hablando, esto recién será el comienzo del fin, su carácter simbólico y su utilización como ícono nacionalista, nos permitirá hacer...
Alemania siglo XXI: un balance
Martha Lucía Quiroga Riviere
2009-01-01
Veinte años han pasado desde que se dieron los sucesos en la República Democrática Alemana (RDA) que llevarían, en noviembre de 1989, a la caída del muro de Berlín y a la reunificación de Alemania el 3 de octubre de 1990. El proceso de unificación alemana dio pie en sus comienzos a una optimista visión que, sin embargo, con el paso del tiempo ha cambiado de tal forma que hoy se habla del ‘messogiorno alemán’ para designar a la zona oriental comparándola con la zona deprimida del sur de Italia...
¿Armas de convicción masiva?. American studies durante la guerra fría: el caso español
Rodríguez Jiménez, Francisco Javier
2009-01-01
[ES] La enseñanza de la lengua y la cultura propias más allá de las fronteras nacionales no sólo no ha dejado de tener importancia con la caída del muro de Berlín, sino que muy posiblemente seguirá siendo una de las cartas importantes de la public diplomacy en los años venideros. Todo apunta pues a que cualquier nación que aspire a jugar un papel destacado en el orden geopolítico internacional no podrá obviar tal “munición”. En esta tesis se trata de ...
Rial, Juan Alberto
2006-01-01
Los autores, a lo largo de diversos capítulos, analizan las cuestiones centrales que hacen a la interacción entre civiles y militares, en lo que tiene que ver con la convivencia, los valores compartidos, la educación, haciendo un análisis de cómo se planteaban estos diversos tópicos antes de la caída del muro de Berlín, y cómo se presentan en la actualidad (tanto en el país como en otros que se utilizan de manera emblemática), y se hace una propuesta de cómo trabajar aquellos que aparecen com...
Una antorcha por la libertad: el legado de Jan Palach, cuatro décadas después
Gabriela E. Vieyra Balboa
2011-01-01
A veinte años de la caída del muro de Berlín y el colapso del comunismo soviético en Europa Central y del Este, en el presente artículo se reflexiona sobre el papel de la disidencia en el proceso de transición democrática llevado a cabo en la antigua República de Checoslovaquia, desde la Primavera de Praga en 1968 a la Revolución de Terciopelo en 1989. Como eje de di- cha reflexión, se rememora y analiza el impacto de una muestra concreta de la mencionada disidencia, la muerte del estudiante ...
Vidal-Beneyto, José
2003-01-01
El artículo trata de los cambios sucedidos tras la caída del muro de Berlín en 1989. El fin de la confrontación entre bloques con la desaparición de la Unión Soviética puso fin al orden mundial surgido tras la segunda guerra mundial. En ese mismo periodo, la revolución de las telecomunicaciones y los avances de la biotecnología anunciaban el nacimiento de una nueva sociedad, la sociedad de la información. Un nuevo termino hizo fortuna, la globalización. Con la llegada del nuevo siglo las nuev...
El Islam en el mundo árabe: respuesta a una globalización excluyente
Rosa Duro Montealegre
2004-01-01
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 representa...
我国公司治理准则的完善——兼评英国2003年公司治理联合准则
Institute of Scientific and Technical Information of China (English)
邱进前
2005-01-01
自上世纪80年代以来，公司治理已成为全球经济学家和法学家所共同关注和研究的国际性课题。传统的公司治理研究主要建立在伯利(Berle)和米恩斯(Means)的著名论断——所有权与控制权分离(The Separation of Ownership and Control)基础之上，拥有资金而缺乏管理能力的股东把公司的经营管理权委托给拥有管理技术而缺乏资金的公司管理者，上市公司两权分离的普遍存在导致了代理问题的产生，
Aulas sin muros: Hacia una casa común educativa
Directory of Open Access Journals (Sweden)
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.
Escenarios sobre el orden internacional
Directory of Open Access Journals (Sweden)
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.
Entre guerra y paz. América Latina frente a la tragedia del primer conflicto mundial
Directory of Open Access Journals (Sweden)
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.
Directory of Open Access Journals (Sweden)
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...
La Formación de la Comunidad de Inteligencia Española: Un proceso en marcha
Directory of Open Access Journals (Sweden)
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.…
El Islam en el mundo árabe: respuesta a una globalización excluyente
Directory of Open Access Journals (Sweden)
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.
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...
Johannes Maerk; Heinz Nissel
2015-01-01
Durante décadas hubo relaciones desiguales y unilaterales entre el llamado "Primer Mundo" "y el "Tercer Mundo". Los donantes determinaron las condiciones para la prestación de ayuda a “los parientes pobres" del Sur. Ni organizaciones como la ONU o el Grupo de los 77 (el movimiento de Países No Alineados) que hoy en día cuenta con más de cien miembros podían cambiar esta situación sustancialmente. Con el fin de la Guerra Fría y la caída del muro de Berlín, sin embargo, la situación geopolítica...
Nappi, Paolino
2014-01-01
La película Cesare deve morire, de los hermanos Taviani, vencedora del Oso de Oro en el Festival de Berlín de 2012, es una obra interesante tanto para un estudioso de cine como de teatro. El filme introduce al espectador en el mundo del teatro realizado en la cárcel, una práctica que en Italia cuenta ya con una historia de más de treinta años y un gran número de experiencias. Esta obra, clasificable dentro del riquísimo panorama contemporáneo italiano del llamado cine de lo real, se sitúa en ...
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)
Un calco Cervantino: Dios es grande
Directory of Open Access Journals (Sweden)
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.
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.
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.
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
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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.
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
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......) for tubes of length L, radius r, permeability kappa and fluid viscosity eta. The experiments (which are in the small M regime) are in good quantitative agreement with the theory. The applicability of our results to plants is discussed and it is shown that it is probable that the Munch mechanism can account...
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.
Directory of Open Access Journals (Sweden)
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.
Directory of Open Access Journals (Sweden)
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.
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.
Renyi entropy of the critical O(N) model
Mukherjee, Anirbit
2015-01-01
In this article we explore a certain definition of "alternate quantization" for the critical O(N) model. We elaborate on a prescription to evaluate the Renyi entropy of alternately quantized critical O(N) model. We show that there exists new saddles of the q-Renyi free energy functional corresponding to putting certain combinations of the Kaluza-Klein modes into alternate quantization. This leads us to an analysis of trying to determine the true state of the theory by trying to ascertain the global minima among these saddle points.
Conrad Martens
2007-01-01
Drawing. The sky is blank; the sun shines from behind Martens' vantage point. The annotation in the base left reads: "Page 48 Vol 3". Two human figures stand in the left centre and centre of the picture, behind whom a saddled horse is sketched flank-on facing right. To its right a second saddled horse stands head-on to the viewer. The annotation beneath the left centre figure reads: "Gaucho"; that beneath the left-hand horse: "darkest[?] horse"; that beneath the right-hand horse probably: "pa...
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.
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.
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.
Complex solutions for the scalar field model of the Universe
Lyons, Glenn W.
1992-08-01
The Hartle-Hawking proposal is implemented for Hawking's scalar field model of the Universe. For this model the complex saddle-point geometries required by the semiclassical approximation to the path integral cannot simply be deformed into real Euclidean and real Lorentzian sections. Approximate saddle points are constructed which are fully complex and have contours of real Lorentzian evolution. The semiclassical wave function is found to give rise to classical spacetimes at late times and extra terms in the Hamilton-Jacobi equation do not contribute significantly to the potential.
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 $p$....
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.
Collision of highly charged ion with clusters. Simulation study for electronic systems
International Nuclear Information System (INIS)
Collision of highly charged ion with cluster, for example, collision of C60-Ar8+ 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 C60 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.)
Vortex Dynamics in Cerebral Aneurysms
Byrne, Greg
2013-01-01
We use an autonomous three-dimensional dynamical system to study embedded vortex structures that are observed to form in computational fluid dynamic simulations of patient-specific cerebral aneurysm geometries. These structures, described by a vortex which is enclosed within a larger vortex flowing in the opposite direction, are created and destroyed in phase space as fixed points undergo saddle-node bifurcations along vortex core lines. We illustrate how saddle-node bifurcations along vortex core lines also govern the formation and evolution of embedded vortices in cerebral aneurysms under variable inflow rates during the cardiac cycle.
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.
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...... Hopf bifurcations. Even when the equilibrium state is stable, weakly damped oscillations occur with a period of 1 min. If, in an attempt to compensate for these oscillations, the thrust deflection is periodically adjusted, a complicated structure of overlapping torus, saddle-node and period......-doubling bifurcations arises. This structure is investigated by combining brute force bifurcation diagrams with one- and two-dimensional continuation analyses....
Higher Rank ABJM Wilson Loops from Matrix Models
Cookmeyer, Jonathan; Zayas, Leopoldo A Pando
2016-01-01
We compute the vacuum expectation values of $1/6$ supersymmetric Wilson loops in higher dimensional representations of the gauge group in ABJM theory. We present results for the $m$-symmetric and $m$-antisymmetric representations by exploiting standard matrix model techniques. At leading order, in the saddle point approximation, our expressions reproduce holographic results from both D6 and D2 branes corresponding to the antisymmetric and symmetric representations, respectively. We also compute 1/N corrections to the leading saddle point results.
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.)
Multi-phase induced inflation in theories with non-minimal coupling to gravity
Artymowski, Michal; Lewicki, Marek
2016-01-01
In this paper we investigate the induced inflation with two flat regions: one Starobinsky-like plateau in big field regime and one shorter plateau around the saddle point of the Einstein frame potential. This multi-phase inflationary scenario can be used to solve the problem of classical cosmology. 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 $\\alpha$-attractors.
The Pearcey integral in the highly oscillatory region
Lopez, Jose L.; Pagola, Pedro
2015-01-01
We consider the Pearcey integral $P(x,y)$ for large values of $\\vert y\\vert$ and bounded values of $\\vert x\\vert$. The integrand of the Pearcey integral oscillates wildly in this region and the asymptotic saddle point analysis is complicated. Then we consider here the modified saddle point method introduced in [Lopez, P\\'erez and Pagola, 2009]. With this method, the analysis is simpler and it is possible to derive a complete asymptotic expansion of $P(x,y)$ for large $\\vert y\\vert$. The asymp...
Liu, Yang; Si, Zong-Guo
2009-01-01
In this paper, we revisit the idea of locked inflation, which suffered from the problems associated with "saddle inflation". We propose a scenario based on locked inflation, however, with an alternative evolution mechanism of the "waterfall field" $\\phi$. Instead of rolling down along the potential, the $\\phi$ field will tunnel to end the inflation stage like in old inflation, by which the saddle inflation could be avoided. Further, we study the case of a cascade with several stages of old locked inflation, which can be motivated by the string landscape.
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.
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.
Bifurcation control of nonlinear oscillator in primary and secondary resonance
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
A weakly nonlinear oscillator was modeled by a sort of differential equation, a saddle-node bifurcation was found in case of primary and secondary resonance. To control the jumping phenomena and the unstable region of the nonlinear oscillator, feedback controllers were designed. Bifurcation control equations were obtained by using the multiple scales method. And through the numerical analysis, good controller could be obtained by changing the feedback control gain. Then a feasible way of further research of saddle-node bifurcation was provided. Finally, an example shows that the feedback control method applied to the hanging bridge system of gas turbine is doable.
REGULARIZED SEMICLASSICAL LIMITS: LINEAR FLOWS WITH INFINITE LYAPUNOV EXPONENTS
Athanassoulis, Agissilaos
2015-01-01
Semiclassical asymptotics for linear 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.
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
Multiple homoclinic orbits in conservative and reversible systems.
A.J. Homburg; J. Knobloch
2006-01-01
Abstract: We study dynamics near multiple homoclinic orbits to saddles in conservative and reversible flows. We consider the existence of two homoclinic orbits in the bellows configuration, where the homoclinic orbits approach the equilibrium along the same direction for positive and negative times.
Dynamics of surface diffeomorphisms relative to homoclinic and heteroclinic orbits
Collins, P.J.
2003-01-01
We show how to obtain information about the dynamics of a two-dimensional discrete-time system from its homoclinic and heteroclinic orbits. The results obtained are based on the theory of trellises, which comprise finite-length subsets of the stable and unstable manifolds of a collection of saddle p
Qiu, Y.; Van Gijzen, M.B.; Van Wingerden, J.W.; Verhaegen, M.; Vuik, C.
2014-01-01
In this paper, we consider preconditioning for PDE-constrained optimization problems. The underlying problems yield a linear saddle-point system. We study a class of preconditioners based on multilevel sequentially semiseparable (MSSS) matrix computations. The novel global preconditioner is to make
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:…
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.
Nuclei and models, 2001-2003. DEA fields, particles and matter
International Nuclear Information System (INIS)
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
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.
Boulatov, D. V.
1993-01-01
We give the formula for a simple Wilson loop on a sphere which is valid for an arbitrary QCD$_2$ saddle-point $\\rho(x)$: \\mbox{$W(A_1,A_2)=\\oint \\frac{dx}{2\\pi i} \\exp(\\int dy \\frac{\\rho(y)}{y-x}+A_2x)$}. The strong-coupling-phase solution is investigated.
Analysis of chaotic oscillations induced in two coupled Wilson-Cowan models.
Maruyama, Yuya; Kakimoto, Yuta; Araki, Osamu
2014-06-01
Although it is known that two coupled Wilson-Cowan models with reciprocal connections induce aperiodic oscillations, little attention has been paid to the dynamical mechanism for such oscillations so far. In this study, we aim to elucidate the fundamental mechanism to induce the aperiodic oscillations in the coupled model. First, aperiodic oscillations observed are investigated for the case when the connections are unidirectional and when the input signal is a periodic oscillation. By the phase portrait analysis, we determine that the aperiodic oscillations are caused by periodically forced state transitions between a stable equilibrium and a stable limit cycle attractors around the saddle-node and saddle separatrix loop bifurcation points. It is revealed that the dynamical mechanism where the state crosses over the saddle-node and saddle separatrix loop bifurcations significantly contributes to the occurrence of chaotic oscillations forced by a periodic input. In addition, this mechanism can also give rise to chaotic oscillations in reciprocally connected Wilson-Cowan models. These results suggest that the dynamic attractor transition underlies chaotic behaviors in two coupled Wilson-Cowan oscillators. PMID:24789794
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.
Institute of Scientific and Technical Information of China (English)
Weidong Hu; Li Xiang; Xiurong Wang
2011-01-01
We used MRI to examine 38 healthy females and 38 female patients with empty sella syndrome. Cerebrospinal fluid flow was examined in six regions of interest, including the anterior clinoid processes, posterior clinoid processes, and 1.0 mm, -1.0 mm, 2.0 mm, -2.0 mm from the midpoint of the line between the anterior and posterior clinoid processes. The results revealed no significant differences in cerebrospinal fluid flow velocity and discharge in a single cardiac cycle, or indicators of cardiac cycles in the control group, indicating that the cerebrospinal fluid flow was relatively steady in the saddle area of the normal brain. In the empty sella syndrome group, cerebrospinal fluid hernia into the saddle area triggered a fluctuation of the anterior and posterior clinoid processes in the saddle area, while the flow in other regions in the saddle area was relatively steady; this resulted in significant differences in cerebrospinal fluid flow velocity and discharge, as well as the cardiac cycle.
Hellowell, Mark
2012-01-01
George Osborne has recently outlined new thinking on private financing for major public service projects. Widely criticised as saddling public bodies with long-term debts, the Private Finance Initiative funding model has been used extensively since the 1990s. Mark Hellowell examines whether the Chancellor’s speech outlines a strategic shift or is more semantic.
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...
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.
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...
Membrany corrections to the string anti-string potential in M5-brane theory
Forste, Stefan
1999-01-01
We study the potential between a string and an anti-string source in M5-theory by using the adS/CFT duality conjecture. We find that the next to leading order corrections in a saddle point approximation renormalize the classical result.
75 FR 8035 - Submission for OMB Review; Comment Request
2010-02-23
..., length of stay, method of travel, number of people, and number of pack and saddle stock. The permit and... Application & Medical History Forms. OMB Control Number: 0596-0084. Summary of Collection: Under Public Law 93... must complete a medical history form (FS-1800-3). The applicant's parents or guardian must sign...
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.
Institute of Scientific and Technical Information of China (English)
2007-01-01
In this paper, we investigate the number and the distribution of the limit cycles bifurcated from a kind of degenerate planar polycycles through three singular points: a saddle-node P0, a fine saddle P1 with finite order m∈N, a contractive (attracting) saddle P2 with the hyperbolicity ratio q2(0)■Q. The connection between P0 and P1 is of hh-type and the connection between P0 and P2 is of hp-type. It is assumed that the connections between P0 to P2 and P0 to P1 keep unbroken. We obtain that the cyclicity of this polycycle is not more than 3m+1, which is linearly dependent on the order of the resonant saddle P1 We also show that the cyclicity is not more than m+3 if q2(0)>m, and that the nearer q2(0)is close to 1, the more the limit cycles are bifurcated.
2010-02-24
... the feasibility of the South Slope Pumped Storage Project, located on Brush Hollow Creek, near Penrose... approximately 6,400 acre-feet, retained by a 95-foot-high, 4,900-foot-long earth and rockfill embankment; (3) a...-long earth and rockfill embankment and a 7-foot-high, 140-foot-long earth saddle dam; (4)...
A Newton method for solving continuous multiple material minimum compliance problems
DEFF Research Database (Denmark)
Stolpe, Mathias; Stegmann, Jan
2007-01-01
method, one or two linear saddle point systems are solved. These systems involve the Hessian of the objective function, which is both expensive to compute and completely dense. Therefore, the linear algebra is arranged such that the Hessian is not explicitly formed. The main concern is to solve...
A Newton method for solving continuous multiple material minimum compliance problems
DEFF Research Database (Denmark)
Stolpe, M; Stegmann, Jan
method, one or two linear saddle point systems are solved. These systems involve the Hessian of the objective function, which is both expensive to compute and completely dense. Therefore, the linear algebra is arranged such that the Hessian is not explicitly formed. The main concern is to solve...
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...
Locating transition states using double-ended classical trajectories
Matro, A; Doll, J D
1994-01-01
In this paper we present a method for locating transition states and higher-order saddles on potential energy surfaces using double-ended classical trajectories. We then apply this method to 7- and 8-atom Lennard-Jones clusters, finding one previously unreported transition state for the 7-atom cluster and two for the 8-atom cluster.
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.
Mid-Range Coil Array for Magnetic Resonance Imaging of Small Animals
Solis, S. E.; Tomasi, D.; Rodríguez, A. O.
2008-08-01
The vast majority of articles on MRI RF coils over the past two decades have focused on large coils, where sample losses dominate, or on micro-coils, where sample and capacitor losses are negligible. Few have addressed the mid-range coils, seen in the majority of small-animal applications, where all the sources of loss are important, for example, mouse brain and body coils from 125 to 750 MHz. We developed a four-saddle coil array for magnetic resonance imaging of small animals. The saddle coil elements in the array were evenly distributed to cover the rat's head. The coil array was tuned to the resonant frequency of 170 MHz. Due to the close proximity of the coil elements, it was necessary to decouple the coil array using nonmagnetic trimmers and, it was operated in the transceiver mode and quadrature-driven. To test the coil array performance at high field, phantom images were acquired with our saddle coil array and standard pulse sequences on a research-dedicated 4 Tesla scanner. Ex vivo brain images of a rat were also acquired, and proved the feasibility of the scaled version of a saddle coil array and, its compatibility with standard pulse sequences when used in a high field magnetic resonance imager.
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
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...
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.
Controlling chaotic transients: Yorke's game of survival
DEFF Research Database (Denmark)
Aguirre, Jacobo; D'ovidio, Francesco; Sanjuán, Miguel A. F.
2004-01-01
We consider the tent map as the prototype of a chaotic system with escapes. We show analytically that a small, bounded, but carefully chosen perturbation added to the system can trap forever an orbit close to the chaotic saddle, even in presence of noise of larger, although bounded, amplitude. Th...
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.
43 CFR 36.11 - Special access.
2010-10-01
... transportation such as domestic dogs, horses and other pack or saddle animals is permitted in areas except where... provided in 36 CFR 13.45. The operation of aircraft resulting in the harassment of wildlife is prohibited... Federal agency and another party, or involved in emergency or search and rescue operations is...
36 CFR 1004.20 - Right of way.
2010-07-01
... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Right of way. 1004.20 Section 1004.20 Parks, Forests, and Public Property PRESIDIO TRUST VEHICLES AND TRAFFIC SAFETY § 1004.20 Right of way. An operator of a motor vehicle shall yield the right of way to pedestrians, saddle and...
Partition function of N=2* SYM on a large four-sphere
Hollowood, Timothy J
2015-01-01
We examine the partition function of N=2* supersymmetric SU(N) Yang-Mills theory on the four-sphere in the large radius limit. We point out that the large radius partition function, at fixed N, is computed by saddle points lying on particular walls of marginal stability on the Coulomb branch of the theory on R^4. For N an even (odd) integer and \\theta_YM=0, (\\pi), these include a point of maximal degeneration of the Donagi-Witten curve to a torus where BPS dyons with electric charge [N/2] become massless. We argue that the dyon singularity is the lone saddle point in the SU(2) theory, while for SU(N) with N>2, we characterize potentially competing saddle points by obtaining the relations between the Seiberg-Witten periods at such points. Using Nekrasov's instanton partition function, we solve for the maximally degenerate saddle point and obtain its free energy as a function of g_YM and N, and show that the results are "large-N exact". In the large-N theory our results provide analytical expressions for the pe...
Dynamics of delay-coupled excitable neural systems
Dahlem, M. A.; Hiller, G; Panchuk, A.; Schoell, E.
2008-01-01
We study the nonlinear dynamics of two delay-coupled neural systems each modelled by excitable dynamics of FitzHugh-Nagumo type and demonstrate that bistability between the stable fixed point and limit cycle oscillations occurs for sufficiently large delay times and coupling strength. As the mechanism for these delay-induced oscillations we identify a saddle-node bifurcation of limit cycles.
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.
Generators of quasiperiodic oscillations with three-dimensional phase space
DEFF Research Database (Denmark)
Kuznetsov, A.P.; Kuznetsov, S.P.; Mosekilde, Erik;
2013-01-01
Considering a family of three-dimensional oscillators originating in the field of radio-engineering, the paper describes three different mechanisms of torus formation. Particular emphasis is paid to a process in which a saddle-node bifurcation eliminates a stable cycle and leaves the system to fi...
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…
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.
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
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
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.
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
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.
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,
Euclidean solutions in Einstein-Yang-Mills-dilaton theory
Brihaye, Y
2006-01-01
We present arguments for the existence of a new type of solutions of the Euclidean Einstein-Yang-Mills-dilaton theory in $d=4$ dimensions. Possesing nonvanishing nonabelian charges, these nonselfdual configurations have no counterparts on the Lorentzian section. They provide, however, new saddle points in the Euclidean path integral.
Conceptual design of the warm dipole magnet for the ALICE forward muon spectrometer
Arkhipov, E V; CERN. Geneva; Datskov, V I; Puzynin, I V; Shabunov, A V; Shelaev, I A; Shishov, Yu A; Tsvineva, G P; Vodopyanov, A S; Yuldasheva, M B; Yuldashev, O I
1996-01-01
A conceptual design study of a conventional dipole magnet for the forward arm muon spectrometer for ALICE experiment was performed. The aluminium conductor coil of the saddle shape was proposed. The 3D magnetic field calculations were performed. The reasonable field quality is obtained. The power consumption is 3.5MW.
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.
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
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
General classical solutions in the CPsup(n-1) model
International Nuclear Information System (INIS)
We study the classical solutions with finite action of the CPsup(n-1) non-linear sigma model in two dimensions. The general solution can be expressed explicitly in terms of n rational analytic functions. All solutions which are neither instantons nor anti-instantons turn out to be saddle points of the action
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.
Common cycling injuries. Management and prevention.
Mellion, M B
1991-01-01
The increasing participation in the athletic forms of bicycling warrants expanded physician attention to the traumatic and overuse injuries experienced by cyclists. The modern bicycle consists of a frame with various components, including handlebars, brakes, wheels, pedals, and gears, in various configurations for the various modes of cycling. For high performance cycling the proper fit of the bicycle is critical. The most efficient method to provide an accurate fit is the Fitkit, but proper frame selection and adjustment can be made by following simple guidelines for frame size, seat height, fore and aft saddle position, saddle angle, reach and handlebar height. The human body functions most effectively in a narrow range of pedal resistance to effort. Riding at too much pedal resistance is a major cause of overuse problems in cyclists. Overuse injuries are lower using lower gear ratios at a higher cadence. Cycling injuries account for 500,000 visits per year to emergency rooms in the US. Over half the accidents involve motor vehicles, and road surface and mechanical problems with the bicycle are also common causes of accidents. Head injuries are common in cyclists and account for most of the fatal accidents. Despite good evidence of their effectiveness, victims with head injuries have rarely worn helmets. Contusions, sprains and fractures may occur throughout the body, most commonly to the hand, wrist, lower arm, shoulder, ankle and lower leg. The handlebar and seat have been implicated in a wide variety of abdominal and genital injuries. Abrasions, lacerations and bruises of the skin are the most common traumatic injuries. Trauma may be prevented or reduced by proper protective safety equipment and keeping the bike in top mechanical condition. Anticipation of the errors of others and practising and adopting specific riding strategies also help to prevent traumatic injuries. Management of overuse injuries in cycling generally involves mechanical adjustment as well
Liu, Xiaojun; Hong, Ling; Jiang, Jun
2016-08-01
Global bifurcations include sudden changes in chaotic sets due to crises. There are three types of crises defined by Grebogi et al. [Physica D 7, 181 (1983)]: boundary crisis, interior crisis, and metamorphosis. In this paper, by means of the extended generalized cell mapping (EGCM), boundary and interior crises of a fractional-order Duffing system are studied as one of the system parameters or the fractional derivative order is varied. It is found that a crisis can be generally defined as a collision between a chaotic basic set and a basic set, either periodic or chaotic, to cause a sudden discontinuous change in chaotic sets. Here chaotic sets involve three different kinds: a chaotic attractor, a chaotic saddle on a fractal basin boundary, and a chaotic saddle in the interior of a basin and disjoint from the attractor. A boundary crisis results from the collision of a periodic (or chaotic) attractor with a chaotic (or regular) saddle in the fractal (or smooth) boundary. In such a case, the attractor, together with its basin of attraction, is suddenly destroyed as the control parameter passes through a critical value, leaving behind a chaotic saddle in the place of the original attractor and saddle after the crisis. An interior crisis happens when an unstable chaotic set in the basin of attraction collides with a periodic attractor, which causes the appearance of a new chaotic attractor, while the original attractor and the unstable chaotic set are converted to the part of the chaotic attractor after the crisis. These results further demonstrate that the EGCM is a powerful tool to reveal the mechanism of crises in fractional-order systems.
La pasión de Alexander Crichton
Directory of Open Access Journals (Sweden)
Matusevich, Daniel
2015-12-01
Full Text Available Alexander Crichton was born in Edinburgh in 1763; he graduated from Leyden University and travelled through Berlín, Paris, Stuttgart, Prague and Gotinga to perfect his knowledge in medicine while he establish a deep connection between the social media and the culture of those places. On 1798 he published An inquiry into the nature and origin of Mental Derangement, the only book he wrote dedicated to madness. In this paper we review some questions referred to the general method that the author applies, his contributions to the semiotics of the mind and to the analysis of the process of aging and the function of the attention; we also take a look to his conception of the world of passions and of madness, who influenced Philippe Pinel and Dominique Esquirol and also constitute a cornerstone in the birth of psychiatry.Alexander Crichton, nació en Edimburgo en 1763, se graduó en la Universidad de Leyden y completó su formación médica en Berlín, Paris, Stuttgart, Praga y Gotinga, vinculándose estrechamente con el ambiente social y cultural de esos prestigiosos centros europeos. En el año 1798 publicó An Inquiry into the nature and origin of Mental Derangement (Investigación sobre la naturaleza y el origen del trastorno mental, única obra de su autoría dedicada a la locura. En este artículo se analizan algunas cuestiones referidas al método general que aplica el autor para la concepción de su obra, sus contribuciones a la semiología de la mente, al análisis del proceso de envejecimiento y a la función de la atención, para detenernos, finalmente, en su conceptuación del mundo de las pasiones y de la locura que fueron retomadas por otros autores como Philippe Pinel y Dominique Esquirol, y que constituyeron un antecedente fundamental en el nacimiento de la psiquiatría.
MIES: CONCURSOS EN LA FRIEDRICHSTRASSE / Mies: Competitions in Friedrichstrasse
Directory of Open Access Journals (Sweden)
Cristina Gastón Guirao
2012-11-01
Full Text Available RESUMEN Mies participó en una docena de concursos de arquitectura entre los años 1910 y 1934. En siete ocasiones en emplazamientos situados en el área más céntrica y comercial de Berlín –todas en un área de radio menor a un quilómetro– cuatro veces sobre la misma calle Friedrichstrasse incluso, en dos ocasiones, sobre el mismo emplazamiento. Ahora teniendo la historia completa y con el tiempo transcurrido es factible ver, anticipados en estos concursos, aspectos de su proyectar posterior. La relación entre las propuestas de concurso y lo que efectivamente ejecuta en el plano profesional da la medida de sus anhelos latentes en cada momento –diferencia que va disminuyendo progresivamente conforme pasa el tiempo–. Con 24 años había participado en un concurso importante, el monumento a Bismarck en el año 1910, y dos años más tarde en una competición encubierta para la residencia de los Kröller–Müller, en Wassenaar. Ahora bien, son los concursos de Berlín los que le dan oportunidad de encarar proyectos de relevancia urbana. Este artículo aborda las primeras veces que Mies tiene ocasión de reflexionar sobre la relación entre el edificio y su entorno en la ciudad.SUMMARY Mies participated in a dozen architectural competitions between 1910 and 1934. On seven occasions these competitions involved locations in the most central area of Berlin, all in an area of less than a mile radius, four times on Friedrichstrasse and twice on the same site. Now, with the full story and the fullness of time, it is feasible to see aspects of his later career anticipated in these competitions. The relationship between the competition proposals and what he actually implemented on the professional level is a measure of his latent desires at each moment, a difference that gradually diminished with the passage time. At 24 years of age he had participated in a major competition, the Bismarck memorial in 1910, and two years later in a private
Research on key technologies in design of middle pylon of Taizhou Bridge
Institute of Scientific and Technical Information of China (English)
Ji Lin
2012-01-01
At the middle pylon of a three-pylon two-span suspension bridge, the effect of unbalanced loads on the adjacent spans may result in a series of technical bottlenecks in design, such as stability and anti-slippage between saddles and main cables. This article presents the researches conducted on structure selection and behavior characteristics of middle pylon, interaction mechanism between main cables and saddles and their anti-slippage safety performance, elastic and plastic stability analysis and safety assessment of steel middle pylon, and fatigue design load and method for steel pylon of Taizhou Bridge. According to the research results, a longitudinal inverted Y shape steel middle pylon is used in design, effectively solving many technical difficulties, and this type of pylon has become a suitable middle pylon structural form for many three-ovlon two-soan susoension bridges.
Bachschmid-Romano, Ludovica; Opper, Manfred; Roudi, Yasser
2016-01-01
We describe and analyze some novel approaches for studying the dynamics of Ising spin glass models. We first briefly consider the variational approach based on minimizing the Kullback-Leibler divergence between independent trajectories and the real ones and note that this approach only coincides with the mean field equations from the saddle point approximation to the generating functional when the dynamics is defined through a logistic link function, which is the case for the kinetic Ising model with parallel update. We then spend the rest of the paper developing two ways of going beyond the saddle point approximation to the generating functional. In the first one, we develop a variational perturbative approximation to the generating functional by expanding the action around a quadratic function of the local fields and conjugate local fields whose parameters are optimized. We derive analytical expressions for the optimal parameters and show that when the optimization is suitably restricted, we recover the mea...
Deriving covariant holographic entanglement
Dong, Xi; Rangamani, Mukund
2016-01-01
We provide a gravitational argument in favour of the covariant holographic entanglement entropy proposal. In general time-dependent states, the proposal asserts that the entanglement entropy of a region in the boundary field theory is given by a quarter of the area of a bulk extremal surface in Planck units. The main element of our discussion is an implementation of an appropriate Schwinger-Keldysh contour to obtain the reduced density matrix (and its powers) of a given region, as is relevant for the replica construction. We map this contour into the bulk gravitational theory, and argue that the saddle point solutions of these replica geometries lead to a consistent prescription for computing the field theory Renyi entropies. In the limiting case where the replica index is taken to unity, a local analysis suffices to show that these saddles lead to the extremal surfaces of interest. We also comment on various properties of holographic entanglement that follow from this construction.
SYMMETRIC VORTICAL STRUCTURE AND ITS TOPOLOGICAL STABILITY
Institute of Scientific and Technical Information of China (English)
WANG Gang; LIANG Xin-gang; GANG Ming-li
2005-01-01
Using time-dependent compressible laminar Navier-Stokes equations with a finite volume method incorporating a third-order-accurate discretization scheme, the flow structures around a slender at certain incidences are numerical simulated and typical crossflow patterns are presented. At incidence 10°, these vortical configurations are different at dissimilar axial locations though they are symmetric. At 35°, the symmetric vortical structures still maintain over the slender, yet their interaction at afterbody is intense than that at the forebody since the two vortices have fully developed downstream. The unstable topological structure of trajectory of saddle-to-saddle points and multiple limit cycle are further discussed in topological stability theory. These structures easily produce bifurcation with perturbation. The results support the view of hydrodynamic instability of vortices flow field.
Bifurcation structure of a model of bursting pancreatic cells
DEFF Research Database (Denmark)
Mosekilde, Erik; Lading, B.; Yanchuk, S.;
2001-01-01
One- and two-dimensional bifurcation studies of a prototypic model of bursting oscillations in pancreatic P-cells reveal a squid-formed area of chaotic dynamics in the parameter plane, with period-doubling bifurcations on one side of the arms and saddle-node bifurcations on the other....... The transition from this structure to the so-called period-adding structure is found to involve a subcritical period-doubling bifurcation and the emergence of type-III intermittency. The period-adding transition itself is not smooth but consists of a saddle-node bifurcation in which (n + 1)-spike bursting...... behavior is born, slightly overlapping with a subcritical period-doubling bifurcation in which n-spike bursting behavior loses its stability....
Bifurcations and Stability Boundary of a Power System
Institute of Scientific and Technical Information of China (English)
Ying-hui Gao
2004-01-01
A single-axis ux decay model including an excitation control model proposed in [12,14,16] is studied. As the bifurcation parameter P m (input power to the generator) varies, the system exhibits dynamics emerging from static and dynamic bifurcations which link with system collapse. We show that the equilibrium point of the system undergoes three bifurcations: one saddle-node bifurcation and two Hopf bifurcations. The state variables dominating system collapse are different for different critical points, and the excitative control may play an important role in delaying system from collapsing. Simulations are presented to illustrate the dynamical behavior associated with the power system stability and collapse. Moreover, by computing the local quadratic approximation of the 5-dimensional stable manifold at an order 5 saddle point, an analytical expression for the approximate stability boundary is worked out.
On the CCN [de]activation nonlinearities
Arabas, Sylwester
2016-01-01
We take into consideration the evolution of particle size in a monodisperse aerosol population during activation and deactivation of cloud condensation nuclei (CCN). The phase portrait of the system derived through a weakly-nonlinear analysis reveals a saddle-node bifurcation and a cusp catastrophe. An analytical estimate of the activation timescale is derived through estimation of the time spent in the saddle-node bifurcation bottleneck. Numerical integration of the system portrays two types of activation/deactivation hystereses: one associated with the kinetic limitations on droplet growth when the system is far from equilibrium, and one occurring close to equilibrium and associated with the cusp catastrophe. The hysteretic behaviour close to equilibrium imposes stringent time-resolution constraints on numerical integration, particularly during deactivation.
Dynamics of massive systems and synthesis of superheavy elements
International Nuclear Information System (INIS)
For the synthesis of superheavy elements, it is indispensable to divide the fusion process into two steps : overcoming the Coulomb barrier and passing over the conditional saddle or the ridgeline. To facilitate the understanding of the mechanism which explains the fusion hindrance, we first employ an analytic model with an inverted parabola for the saddle. Then, results by realistic calculations are given for the cold fusion. Ambiguities of the model are also discussed for future investigations. Since the model is general, it is applied to incident channels with neutron-rich projectiles and/or targets. These are necessary for synthesis of nuclides in so-called superheavy island around Z=114 and N=184. (author)
Isotope Dependence of Superheavy Nucleus Formation Cross Section
Institute of Scientific and Technical Information of China (English)
LIU Zu-Hua; BAG Jing-Dong
2006-01-01
The dynamical process in the superheavy nucleus synthesis is studied on the basis of the two-dimensional Smolu-chowski equation. Special attention is paid to the isotope dependence of the cross section for the superheavy nucleus formation by means of making a comparison among the reaction systems of 54Fe + 204Pb, 56Fe + 206Pb, and 58Fe + 208Pb. It is found by this comparison that the formation cross section is very sensitive to the conditional saddle-point height and the neutron separation energy of the compound nucleus. Reaction systems with lower height of conditional saddle-point and smaller neutron separation energy are more favourable for the synthesis of the superheavy nucleus.
Langevin description of the evaporation residue spin distribution
International Nuclear Information System (INIS)
The recently measured spin distribution of evaporation residue cross section in the reaction 16O + 184W is studied in the framework of Langevin equations. Results show that the Langevin approach can describe this observable very well. Moreover, a pre-saddle nuclear viscosity coefficient of 5 × 1021 s-1 is extracted by comparing theoretical calculations with experimental data. We also explore the effect of the isospin of a system on the spin distribution by evaluating the evaporation residue spin distribution of nuclei 194Pb, 200Pb and 206Pb. It has been found that with increasing the isospin of the system, the sensitivity of the evaporation residue spin distribution to the nuclear viscosity is decreased significantly. This result suggests that choosing a low-isospin compound system favors an accurate determination of pre-saddle dissipation strength. (author)
Novel routes to chaos through torus breakdown in non-invertible maps
DEFF Research Database (Denmark)
Zhusubaliyev, Zhanybai; Mosekilde, Erik
2009-01-01
The paper describes a number of new scenarios for the transition to chaos through the formation and destruction of multilayered tori in non-invertible maps. By means of detailed, numerically calculated phase portraits we first describe how three- and five-layered tori arise through period......-doubling and/or pitchfork bifurcations of the saddle cycle on an ordinary resonance torus. We then describe several different mechanisms for the destruction of five-layered tori in a system of two linearly coupled logistic maps. One of these scenarios involves the destruction of the two intermediate layers...... of the five-layered torus through the transformation of two unstable node cycles into unstable focus cycles, followed by a saddle-node bifurcation that destroys the middle layer and a pair of simultaneous homoclinic bifurcations that produce two invariant closed curves with quasiperiodic dynamics along...
State(R)-state(TS)-state(P) theoretical study of H + H2 system
Institute of Scientific and Technical Information of China (English)
SHEN; Changsheng; (沈长圣); JU; Guanzhi; (居冠之); JU; Quan; (居泉)
2002-01-01
The calculation of H + H2 system by symplectic quasiclassical trajectory (SQCT) shows that there are two types of collision trajectories A and B, i.e., type A trajectory passes the saddle point of transition state (TS), whereas type B trajectory does not pass the saddle point of transition state. Not all the reactants of type A trajectory are reactive, while not all of type B trajectory are nonreactive. The partition and reactivity of these two types of trajectories are affected by reactant state(R), furthermore, the types of trajectories affect the state and angle distributions of products. Not only the rudiment framework for theoretical study on state(R)-state(TS)-state(P) is established, but also the further understanding of transition state theory (TST) of Eyring is investigated in this paper.
International Nuclear Information System (INIS)
It is well known that the anatomy of the masticatory muscles is related to craniofacial morphology. We evaluated the relationship between the volume and inclination of the medial pterygoid muscle and craniofacial morphology in subjects with normal occlusion. Muscle volume correlated with FMA, gonial angle, saddle angle, the angle of convexity, SN-GoGn and posterior facial height. Muscle inclination correlated with FH-SN, saddle angle and articulare angle. The asymmetry index of muscle inclination in subjects whose mandible tipped away from the membrum correlated with the Ag line angle and distance ORP to Me. When viewed in the sagittal plane, the volume and inclination of the medial pterygoid muscle affected the position of the mandible and the mandibular fossa. When viewed in the frontal plane, the relationship between the medial pterygoid muscle and craniofacial morphology depended on displacement of the mandible. (author)
Hidden imperfect synchronization of wall turbulence
Tardu, Sedat F.
2010-03-01
Instantaneous amplitude and phase concept emerging from analytical signal formulation is applied to the wavelet coefficients of streamwise velocity fluctuations in the buffer layer of a near wall turbulent flow. Experiments and direct numerical simulations show both the existence of long periods of inert zones wherein the local phase is constant. These regions are separated by random phase jumps. The local amplitude is globally highly intermittent, but not in the phase locked regions wherein it varies smoothly. These behaviors are reminiscent of phase synchronization phenomena observed in stochastic chaotic systems. The lengths of the constant phase inert (laminar) zones reveal a type I intermittency behavior, in concordance with saddle-node bifurcation, and the periodic orbits of saddle nature recently identified in Couette turbulence. The imperfect synchronization is related to the footprint of coherent Reynolds shear stress producing eddies convecting in the low buffer.
De Faria, C F M; Becker, W
2002-01-01
A versatile semiclassical approximation for intense laser-atom processes is presented. This uniform approximation is no more complicated than the frequently-used multi-dimensional saddle-point approximation and far superior, since it applies for all energies, both close to as well as away from classical cutoffs. In the latter case, it reduces to the standard saddle-point approximation. The uniform approximation agrees accurately with numerical evaluations for potentials, for which these are feasible, and constitutes a practicable method of calculation in general. The method is applied to the calculation of high-order above-threshold ionization spectra with various binding potentials: Coulomb, Yukawa, and shell potentials which may model C$_{60}$ molecules or clusters. The shell potentials generate high-order ATI spectra that are more structured and may feature an apparently higher cutoff.
Removing External Degrees of Freedom from Transition-State Search Methods using Quaternions
Melander, Marko; Jonsson, Hannes
2015-01-01
In finite systems, such as nanoparticles and gas-phase molecules, calculations of minimum energy paths (MEPs) connecting initial and final states of transitions as well as searches for saddle points are complicated by the presence of external degrees of freedom, such as overall translation and rotation. A method based on quaternion algebra for removing the external degrees of freedom is described here and applied in calculations using two commonly used methods: the nudged elastic band (NEB) method for MEPs and the DIMER method for finding the minimum mode in minimum mode following searches of first-order saddle points. With the quaternion approach, fewer images in the NEB are needed to represent MEPs accurately. In both NEB and DIMER calculations of finite systems, the number of iterations required to reach convergence is significantly reduced. The algorithms have been implemented in the Atomic Simulation Environment (ASE) open source software.
Removing External Degrees of Freedom from Transition-State Search Methods using Quaternions.
Melander, Marko; Laasonen, Kari; Jónsson, Hannes
2015-03-10
In finite systems, such as nanoparticles and gas-phase molecules, calculations of minimum energy paths (MEPs) connecting initial and final states of transitions as well as searches for saddle points are complicated by the presence of external degrees of freedom, such as overall translation and rotation. A method based on quaternion algebra for removing the external degrees of freedom is described here and applied in calculations using two commonly used methods: the nudged elastic band (NEB) method for MEPs and the DIMER method for finding the minimum mode in minimum mode following searches of first-order saddle points. With the quaternion approach, fewer images in the NEB are needed to represent MEPs accurately. In both NEB and DIMER calculations of finite systems, the number of iterations required to reach convergence is significantly reduced. The algorithms have been implemented in the Atomic Simulation Environment (ASE) open source software. PMID:26579757
International Nuclear Information System (INIS)
Graphical abstract: The structure of a minimum in Ar19K+ cluster. Abstract: In this paper we explore the possibility of using stochastic optimizers, namely simulated annealing (SA) in locating critical points (global minima, local minima and first order saddle points) in Argon noble gas clusters perturbed by alkali metal ions namely sodium and potassium. The atomic interaction potential is the Lennard Jones potential. We also try to see if a continuous transformation in geometry during the search process can lead to a realization of a kind of minimum energy path (MEP) for transformation from one minimum geometry to another through a transition state (first order saddle point). We try our recipe for three sizes of clusters, namely (Ar)16M+, (Ar)19M+ and (Ar)24M+, where M+ is Na+ and K+.
Han, Jie
2014-01-01
We investigate time-dependent probability for a Brownian particle passing over the barrier to stay at a metastable potential pocket against escaping over the barrier. This is related to whole fusion-fission dynamical process and can be called the reverse Kramers problem. By the passing probability over the saddle point of inverse harmonic potential multiplying the exponential decay factor of a particle in the metastable potential, we present an approximate expression for the modified passing probability over the barrier, in which the effect of reflection boundary of potential is taken into account. Our analytical result and Langevin Monte-Carlo simulation show that the probability passing and against escaping over the barrier is a non-monotonous function of time and its maximal value is less than the stationary result of passing probability over the saddle point of inverse harmonic potential.