3,507 research outputs found
La commision de consolidation de la paix: un organe avec un avenir prometteur?
Uno de los primeros resultados del proceso de reforma impulsado por el Secretario General
con ocasión del sesenta aniversario de la Carta ha sido la creación de la Comisión de
Consolidación de la Paz, órgano intergubernamental consultivo, subsidiario del Consejo de
Seguridad y de la Asamblea General. El estudio de su génesis, de sus características principales,
así como de las primeras misiones que le han sido conferidas, permite hacer una aproximación
sobre las posibles repercusiones que tendrá su creación al nivel de la consolidación
de la paz. Se pone entonces de manifiesto el hecho que los resultados esperados de la Comisión
dependen, ante todo, no sólo de la voluntad de los Estados miembros de las Naciones
Unidas, sino también de los demás actores internacionales
Revisiting electric utilities’ efficiency in the Southern African Power Pool, 1998–2009
This study analyses the determinants of the technical efficiency performance for Southern African Power Pool (SAPP) power utilities in the period 1998-2009, excluding South Africa’s Eskom. The study formulated an explicit model for technical inefficiency by considering the vertical structure of the utilities and the definition of the product, considering the specific characteristics of this sample. It was found that the most significant improvement in the average efficiency of the sample occurred from 2000 to 2002, coinciding with the first SAPP Energy Plan of 2001. Density in consumption, control of corruption and load factor also contributed to the different levels of efficiency. The results provided a new empirical evidence that can be useful for the design of energy policy and incentive regulation
Chain Homotopies for Object Topological Representations
This paper presents a set of tools to compute topological information of
simplicial complexes, tools that are applicable to extract topological
information from digital pictures. A simplicial complex is encoded in a
(non-unique) algebraic-topological format called AM-model. An AM-model for a
given object K is determined by a concrete chain homotopy and it provides, in
particular, integer (co)homology generators of K and representative (co)cycles
of these generators. An algorithm for computing an AM-model and the
cohomological invariant HB1 (derived from the rank of the cohomology ring) with
integer coefficients for a finite simplicial complex in any dimension is
designed here. A concept of generators which are "nicely" representative cycles
is also presented. Moreover, we extend the definition of AM-models to 3D binary
digital images and we design algorithms to update the AM-model information
after voxel set operations (union, intersection, difference and inverse)
A Tool for Integer Homology Computation: Lambda-At Model
In this paper, we formalize the notion of lambda-AT-model (where is
a non-null integer) for a given chain complex, which allows the computation of
homological information in the integer domain avoiding using the Smith Normal
Form of the boundary matrices. We present an algorithm for computing such a
model, obtaining Betti numbers, the prime numbers p involved in the invariant
factors of the torsion subgroup of homology, the amount of invariant factors
that are a power of p and a set of representative cycles of generators of
homology mod p, for each p. Moreover, we establish the minimum valid lambda for
such a construction, what cuts down the computational costs related to the
torsion subgroup. The tools described here are useful to determine topological
information of nD structured objects such as simplicial, cubical or simploidal
complexes and are applicable to extract such an information from digital
pictures.Comment: Journal Image and Vision Computing, Volume 27 Issue 7, June, 200
Spatial rogue waves in photorefractive SBN crystals
We report on the excitation of large-amplitude waves, with a probability of
around 1% of total peaks, on a photorefractive SBN crystal by using a simple
experimental setup at room temperature. We excite the system using a narrow
Gaussian beam and observe different dynamical regimes tailored by the value and
time rate of an applied voltage. We identify two main dynamical regimes: a
caustic one for energy spreading and a speckling one for peak emergence. Our
observations are well described by a two-dimensional Schr\"odinger model with
saturable local nonlinearity.Comment: 4 pages, 4 figure
Use of data description languages in the interchange of data
The Consultative Committee for Space Data Systems (CCSDS) is developing Standards for the interchange of information between systems, including those operating under different environments. The objective is to perform the interchange automatically, i.e. in a computer interpretable manner. One aspect of the concept developed by CCSDS is the use of a separate data description to specify the data being transferred. Using the description, data can then be automatically parsed by the receiving computer. With a suitably expressive Data Description Language (DDL), data formats of arbitrary complexity can be handled. The advantages of this approach are: (1) that the description need only be written and distributed once to all users, and (2) new software does not need to be written for each new format, provided generic tools are available to support writing and interpretation of descriptions and the associated data instances. Consequently, the effort of 'hard coding' each new format is avoided and problems of integrating multiple implementations of a given format by different users are avoided. The approach is applicable in any context where computer parsable description of data could enhance efficiency (e.g. within a spacecraft control system, a data delivery system or an archive). The CCSDS have identified several candidate DDL's: EAST (Extended Ada Subset), TSDN (Transfer Syntax Data Notation) and MADEL (Modified ASN.1 as a Data Description Language -- a DDL based on the Abstract Syntax Notation One - ASN.1 - specified in the ISO/IEC 8824). This paper concentrates on ESA's development of MADEL. ESA have also developed a 'proof of concept' prototype of the required support tools, implemented on a PC under MS-DOS, which has successfully demonstrated the feasibility of the approach, including the capability within an application of retrieving and displaying particular data elements, given its MADEL description (i.e. a data description written in MADEL). This paper outlines the work done to date and assesses the applicability of this modified ASN.1 as a DDL. The feasibility of the approach is illustrated with several examples
Los países BRICS en un mundo globalizado: ¿algo más que actores económicos?
Este trabajo pretende analizar si los países BRICS, que hoy en día se consideran potencias económicas (aunque con diferencias notables entre ellos y algunos interrogantes), pueden aspirar a un papel más activo en la Comunidad internacional. Por ello, después de haber abordado las cuestiones económicas, trataremos de las nuevas herramientas creadas por el grupo para la ayuda al desarrollo y nos detendremos sobre diferentes cuestiones relativas a la dimensión de la paz y seguridad internacionales.This paper aims to analyse whether BRICS, economic powers (regardless of some obstacles) may pretend to acquire a more active role in the International Community. Therefore, having addressed economic issues, we discuss new tools created by this group for the assistance development. In addition, several aspects related to the international peace and security are also examined
La cuestión de la representación única de la Unión Europea en el Consejo de Seguridad de las Naciones Unidas
Con ocasión del debate sobre la reforma de la composición del Consejo de Seguridad de las Naciones Unidas, se ha llegado a plantear si sería posible una representación única de la Unión Europea en su seno. Este trabajo versa sobre el análisis de los dos tipos de dificultades en presencia. Lo primero de ellas es de orden jurídico y corresponde al necesario respeto de las disposiciones de la Carta de Naciones Unidas así como del Derecho Primario de la UE. Lo
segundo se refiere a los intereses políticos en juego y a la predisposición de los Estados en aceptar la representación única de una Organización regional en el Consejo de Seguridad de las Naciones Unidas
Analyses of thermal storage capacity and smart grid flexibility in Danish single-family houses
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