Medida de concentración de Gini : Observaciones sobre las fórmulas de cálculo y el Principio de Población de Dalton. Propuesta de un factor de corrección

En la primera parte del presente trabajo se investigan diferentes formas de cálculo de la razón de concentración conocida como Coeficiente o Índice de Gini, y el no cumplimiento del axioma conocido como de "invariancia a la replicación" o "Principio de Población de Dalton" en algunas de ellas. El alcance de las conclusiones se limita al comportamiento de las fórmulas sometidas a prueba (se encuentran entre las más conocidas) cuando son aplicadas a distribuciones de datos desagregados. En la segunda parte se propone un factor de corrección para las fórmulas de cálculo analizadas, de manera que satisfagan el Principio de Población.

An Oka principle for equivariant isomorphisms

Let G be a reductive complex Lie group acting holomorphically on normal Stein spaces X and Y, which are locally G-biholomorphic over a common categorical quotient Q. When is there a global G-biholomorphism X → Y? If the actions of G on X and Y are what we, with justification, call generic, we prove that the obstruction to solving this local-to-global problem is topological and provide sufficient conditions for it to vanish. Our main tool is the equivariant version of Grauert's Oka principle due to Heinzner and Kutzschebauch. We prove that X and Y are G-biholomorphic if X is K-contractible, where K is a maximal compact subgroup of G, or if X and Y are smooth and there is a G-diffeomorphism ψ : X → Y over Q, which is holomorphic when restricted to each fibre of the quotient map X → Q. We prove a similar theorem when ψ is only a G-homeomorphism, but with an assumption about its action on G-finite functions. When G is abelian, we obtain stronger theorems. Our results can be interpreted as instances of the Oka principle for sections of the sheaf of G-biholomorphisms from X to Y over Q. This sheaf can be badly singular, even for a low-dimensional representation of SL2(ℂ). Our work is in part motivated by the linearisation problem for actions on ℂn. It follows from one of our main results that a holomorphic G-action on ℂn, which is locally G-biholomorphic over a common quotient to a generic linear action, is linearisable.

Testing the Weak Equivalence Principle with an antimatter beam at CERN

The goal of the AEgIS experiment is to measure the gravitational acceleration of antihydrogen – the simplest atom consisting entirely of antimatter – with the ultimate precision of 1%. We plan to verify the Weak Equivalence Principle (WEP), one of the fundamental laws of nature, with an antimatter beam. The experiment consists of a positron accumulator, an antiproton trap and a Stark accelerator in a solenoidal magnetic field to form and accelerate a pulsed beam of antihydrogen atoms towards a free-fall detector. The antihydrogen beam passes through a moir ́e deflectometer to measure the vertical displacement due to the gravitational force. A position and time sensitive hybrid detector registers the annihilation points of the antihydrogen atoms and their time-of-flight. The detection principle has been successfully tested with antiprotons and a miniature moir ́e deflectometer coupled to a nuclear emulsion detector.

Asymmetries and shortages of the network neutrality principle: What could neutrality achieve?

The debate on network neutrality has reached sufficient notoriety to eliminate the need for detailed explanation. A simple definition will suffice: “network neutrality” is understood as the principle by which the owners of broadband networks would not be allowed to establish any type of discrimination or preference over the traffic transmitted through them

Topological invariance and spatial scaling of surface roughness in two highly eroded zones of Mexico: a comparative study

The Fractal Image Informatics toolbox (Oleschko et al., 2008 a; Torres-Argüelles et al., 2010) was applied to extract, classify and model the topological structure and dynamics of surface roughness in two highly eroded catchments of Mexico. Both areas are affected by gully erosion (Sidorchuk, 2005) and characterized by avalanche-like matter transport. Five contrasting morphological patterns were distinguished across the slope of the bare eroded surface of Faeozem (Queretaro State) while only one (apparently independent on the slope) roughness pattern was documented for Andosol (Michoacan State). We called these patterns ?the roughness clusters? and compared them in terms of metrizability, continuity, compactness, topological connectedness (global and local) and invariance, separability, and degree of ramification (Weyl, 1937). All mentioned topological measurands were correlated with the variance, skewness and kurtosis of the gray-level distribution of digital images. The morphology0 spatial dynamics of roughness clusters was measured and mapped with high precision in terms of fractal descriptors. The Hurst exponent was especially suitable to distinguish between the structure of ?turtle shell? and ?ramification? patterns (sediment producing zone A of the slope); as well as ?honeycomb? (sediment transport zone B) and ?dinosaur steps? and ?corals? (sediment deposition zone C) roughness clusters. Some other structural attributes of studied patterns were also statistically different and correlated with the variance, skewness and kurtosis of gray distribution of multiscale digital images. The scale invariance of classified roughness patterns was documented inside the range of five image resolutions. We conjectured that the geometrization of erosion patterns in terms of roughness clustering might benefit the most semi-quantitative models developed for erosion and sediment yield assessments (de Vente and Poesen, 2005).

A technique for recursive invariance detection and selective program specialization

This paper presents a technique for achieving a class of optimizations related to the reduction of checks within cycles. The technique uses both Program Transformation and Abstract Interpretation. After a ñrst pass of an abstract interpreter which detects simple invariants, program transformation is used to build a hypothetical situation that simpliñes some predicates that should be executed within the cycle. This transformation implements the heuristic hypothesis that once conditional tests hold they may continué doing so recursively. Specialized versions of predicates are generated to detect and exploit those cases in which the invariance may hold. Abstract interpretation is then used again to verify the truth of such hypotheses and conñrm the proposed simpliñcation. This allows optimizations that go beyond those possible with only one pass of the abstract interpreter over the original program, as is normally the case. It also allows selective program specialization using a standard abstract interpreter not speciñcally designed for this purpose, thus simplifying the design of this already complex module of the compiler. In the paper, a class of programs amenable to such optimization is presented, along with some examples and an evaluation of the proposed techniques in some application áreas such as floundering detection and reducing run-time tests in automatic logic program parallelization. The analysis of the examples presented has been performed automatically by an implementation of the technique using existing abstract interpretation and program transformation tools.

Invariance of the Glass Transition Temperature of Plant Vitrification Solutions with Cooling Rate

The solutions studied were Plant Vitrification Solutions 1, 2 and 3: (PVS1: Uragami et al. 1989, Plant Cell Rep. 8, 418; PVS2: Sakai et al. 1990, Plant Cell Rep. 9, 30; PVS3: Nishizawa et al. 1993, Plant Sci. 91, 67). Cooling was performed using the calorimeter control (5, 10 and 20°C min-1), or for higher rates, by quenching the closed pan with PVS in LN, either naked (faster - 5580°C min-1) or introduced in cryovials (reduced rate 360°C min-1). Quenched pans were then transferred to the sample chamber, pre-cooled to -196°C. Glass transition temperature was observed by DSC with a TA 2920 instrument, upon warming pans with solution samples from -145°C to room temperature, at standard warming rate10°C min-1.

Co2 capture in power plants-using the oxy-combustion principle

In the C02 capture from power generation, the energy penalties for the capture are one of the main challenges. Nowadays, the post-combustion methods have energy penalties 10wer than the oxy combustion and pre-combustion technologies. One of the main disadvantages of the post combustion method is the fact that the capture ofC02at atmospheric pressure requires quite big equipment for the high flow rates of flue gas, and the 10w partial pressure of the CO2generates an important 10ss of energy. The A1lam cyc1e presented for NETPOWER gives high efficiencies in the power production and 10w energy penalties. A simulation of this cyc1e is made together with a simulation of power plants with pre-combustion and post-combustion capture and without capture for natural gas and forcoa1. The simulations give 10wer efficiencies than the proposed for NETPOWER For natural gas the efficiency is 52% instead of the 59% presented, and 33% instead of51% in the case of using coal as fuel. Are brought to light problems in the CO2compressor due the high flow ofC02that is compressed unti1300 bar to be recyc1ed into the combustor.

Hoshin Kanri. Principle Centered Leadership

The purpose of this paper is to sketch the outlines of what will, hopefully become my PhD thesis: the proposal of an evolutional leadership behavioral pattern, Hoshin Kanri, that enables process owners in organizations attain alignment by achieving their goals while increasing trust. ! I intend to develop such a behavioral pattern or “proper way” 善道 1 by adopting a network perspective over two organizational dimensions: process dimension and process owner dimension. In both dimensions I will propose measures of their topological structure and functionality. From there I will propose quantifiable characteristics that will help me enunciate several hypothesis about their dynamical and evolutional characteristics. I intend to test these hypothesis in the field and report the results to enable others to challenge this research.

On the harmonic analysis of cup anemometer rotation speed: A principle to monitor performance and maintenance status of rotating meteorological sensors

The calibration results of one anemometer equipped with several rotors, varying their size, were analyzed. In each case, the 30-pulses pert turn output signal of the anemometer was studied using Fourier series decomposition and correlated with the anemometer factor (i.e., the anemometer transfer function). Also, a 3-cup analytical model was correlated to the data resulting from the wind tunnel measurements. Results indicate good correlation between the post-processed output signal and the working condition of the cup anemometer. This correlation was also reflected in the results from the proposed analytical model. With the present work the possibility of remotely checking cup anemometer status, indicating the presence of anomalies and, therefore, a decrease on the wind sensor reliability is revealed.

La paradoja de Mies : las simetrías invisibles a través del Pabellón de Barcelona

El vínculo de Mies van der Rohe con la simetría es un invariante que se intuye en toda su obra más allá de su pretendida invisibilidad. Partiendo del proyecto moderno como proceso paradójico, que Mies lo expresa en sus conocidos aforismos, como el célebre “menos es más”, la tesis pretende ser una aproximación a este concepto clave de la arquitectura a través de una de sus obras más importantes: el Pabellón Alemán para la Exposición Universal de 1.929 en Barcelona. Ejemplo de planta asimétrica según Bruno Zevi y un “auténtico caballo de Troya cargado de simetrías” como lo definió Robin Evans. El Pabellón representó para la modernidad, la culminación de una década que cambió radicalmente la visión de la arquitectura hasta ese momento, gracias al carácter inclusivo de lo paradójico y las innumerables conexiones que hubo entre distintas disciplinas, tan antagónicas, como el arte y la ciencia. De esta última, se propone una definición ampliada de la simetría como principio de equivalencia entre elementos desde la invariancia. En esta definición se incorpora el sentido recogido por Lederman como “expresión de igualdad”, así como el planteado por Hermann Weyl en su libro Simetría como “invariancia de una configuración bajo un grupo de automorfismos” (libro que Mies tenía en su biblioteca privada). Precisamente para Weyl, el espacio vacío tiene un alto grado de simetría. “Cada punto es igual que los otros, y en ninguno hay diferencias intrínsecas entre las diversas direcciones." A partir de este nuevo significado, la obra de Mies adquiere otro sentido encaminado a la materialización de ese espacio, que él pretendía que “reflejase” el espíritu de la época y cuya génesis se postula en el Teorema de Noether que establece que “por cada simetría continua de las leyes físicas ha de existir una ley de conservación”. Estas simetrías continúas son las simetrías invisibles del espacio vacío que se desvelan “aparentemente” como oposición a las estructuras de orden de las simetrías de la materia, de lo lleno, pero que participan de la misma lógica aporética miesiana, de considerarlo otro material, y que se definen como: (i)limitado, (in)grávido, (in)acabado e (in)material. Finalmente, una paradoja más: El “espacio universal” que buscó Mies, no lo encontró en América sino en este pabellón. Como bien lo han intuido arquitectos contemporáneos como Kazuyo Sejima + Ryue Nishizawa (SANAA) legítimos herederos del maestro alemán. ABSTRACT The relationship between Mies van der Rohe with the symmetry is an invariant which is intuited in his entire work beyond his intentional invisibility. Based on the modern project as a paradoxical process, which Mies expresses in his aphorisms know as the famous “less is more”, the thesis is intended to approach this key concept in architecture through one of his most important works: The German Pavilion for the World Expo in 1929 in Barcelona, an example of asymmetric floor according to Bruno Zevi and a “real Trojan horse loaded with symmetries”. As defined by Robin Evans. For modernity, this Pavilion represented the culmination of a decade which radically changed the vision of architecture so far, thanks to the inclusive character of the paradoxical and the innumerable connections that there were amongst the different disciplines, as antagonistic as Art and Science. Of the latter, an expanded definition of symmetry is proposed as the principle of equivalence between elements from the invariance. Incorporated into this definition is the sense defined by Leterman as “expression of equality,” like the one proposed by Hermann Weyl in his book Symmetry as “configuration invariance under a group of automorphisms” (a book which Mies had in his private library). Precisely for Weyl, the empty space has a high degree of symmetry. “Each point is equal to the other, and in none are there intrinsic differences among the diverse directions.” Based on this new meaning, Mies’ work acquires another meaning approaching the materialization of that space, which he intended to “reflect” the spirit of the time and whose genesis is postulated in the Noether’s theorem which establishes that “for every continuous symmetry of physical laws, there must be a law of conservation.” These continuous symmetries are the invisible empty space symmetries which reveal themselves “apparently” as opposition to the structures of matter symmetries, of those which are full, but which participate in the same Mies aporetic logic, if deemed other material, and which is defined as (un)limited, weight(less), (un)finished and (im)material. Finally, one more paradox: the “universal space” which Mies search for, he did not find it in America, but at this pavilion, just as the contemporary architects like Kazuyo Sejima + Ryue Nishizawa (SANAA) rightfully intuited, as legitimate heirs of the German master.

The optimization principle in phylogenetic analysis tends to give incorrect topologies when the number of nucleotides or amino acids used is small

In the maximum parsimony (MP) and minimum evolution (ME) methods of phylogenetic inference, evolutionary trees are constructed by searching for the topology that shows the minimum number of mutational changes required (M) and the smallest sum of branch lengths (S), respectively, whereas in the maximum likelihood (ML) method the topology showing the highest maximum likelihood (A) of observing a given data set is chosen. However, the theoretical basis of the optimization principle remains unclear. We therefore examined the relationships of M, S, and A for the MP, ME, and ML trees with those for the true tree by using computer simulation. The results show that M and S are generally greater for the true tree than for the MP and ME trees when the number of nucleotides examined (n) is relatively small, whereas A is generally lower for the true tree than for the ML tree. This finding indicates that the optimization principle tends to give incorrect topologies when n is small. To deal with this disturbing property of the optimization principle, we suggest that more attention should be given to testing the statistical reliability of an estimated tree rather than to finding the optimal tree with excessive efforts. When a reliability test is conducted, simplified MP, ME, and ML algorithms such as the neighbor-joining method generally give conclusions about phylogenetic inference very similar to those obtained by the more extensive tree search algorithms.