4,987 research outputs found
An introduction to financial and economic modeling for utility regulators
The most effective regulators in developing countriesare following remarkably similar approaches. The main common element across"best practice"countries is the use of relatively simple quantitative models of operators'behavior and constraints to measure the impact of regulatory decisions on some key financial and economic indicators of concern to the operators, the users, and the government. The authors provide an introduction to the design and use of these models. They draw on lessons from international experience in industrial and developing countries in ordinary or extraordinary revisions and in the context of contract renegotiations. Simplifying somewhat, these models force regulators to recognize that, in the long run, private operators need to at least cover their opportunity cost of capital, including the various types of risks specific to the country, the sector, or the projects with which they are involved. Because these variables change over time, scheduled revisions are needed to allow for adjustments in the key determinants of the rate of return of the operator. These revisions are a recognition of the fact that all these determinants-tariffs, subsidies, quality, investments, and other service obligations-are interrelated and jointly determine the rate of return. At every revision, the rules of the game for the regulator are exactly the same: to figure out the changes in the cost of capital and to adjust the variables driving the rate of return to ensure that it continues to be consistent with the cost of capital. If they can draw on reasonable data, these models do everything any financial model would do for the day-to-day management of a company but take a longer term view and include an explicit identification of the key regulatory instruments. They can monitor the consistency between cash flow generated by the business on the one hand and debt service and operational expense needs on the other to address the main concerns of the operators. They can also account for a large number of key policy factors including access and affordability concerns for various types of consumers. They generally account for the sensitivity of operators and users to various regulatory design options.Payment Systems&Infrastructure,Economic Theory&Research,Decentralization,Environmental Economics&Policies,Enterprise Development&Reform,Public Sector Economics&Finance,Environmental Economics&Policies,Economic Theory&Research,Banks&Banking Reform,Municipal Financial Management
Activated carbons as catalytic support for Cu nanoparticles
There are a wide range of catalytic applications for Cu-based nanoparticles materials, since Cu is an
abundant and inexpensive metal and Cu nanoparticles possess unusual electrical, thermal and
optical properties. The possible modification of the chemical and physical properties of these
nanoparticles using different synthetic strategies and conditions and/or via postsynthetic chemical
treatments has been largely responsible for the rapid growth of interest in these nanomaterials and
their applications in catalysis. A previous work have explored the possibilities of SBA-15 (1,2) as
support for Cu nanoparticles. In the present contribution, those results will be compared with the
use of a carbon material as support, since activated carbon present many advantages with respect
SBA, as the high surface area.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Models for Type I X-Ray Bursts Nucleosynthesis with Parallelisation and Improved Nuclear Physics
Type I XRBs are thermonuclear flashes on the surface of neutron stars (NS) associated
with mass-accretion from a companion star. Models of type I XRBs and their associated
nucleosynthesis are physically complicated and extremely intense as regards the huge
computational power required to model the physical processes played out, with the required
precision to be truly representative. Until recently, because of these computational
limitations, studies of XRB nucleosynthesis have been performed using limited nuclear
reaction networks. In the bid to overcome this hurdle, parallel computing has been raised as
the main permitting factor of yet more precise and computationally intensive simulations as
it offers the potential to concentrate computational resources on intensive computational
problems. In this Work, we present a parallelisation of two different applications; a one-zone
(i.e. parameterized) nucleosynthesis code, and a one-dimensional (spherically symmetric),
hydrodynamic code, in Lagrangian formulation (hereafter SHIVA code), built originally to
model classical nova outbursts (José 1996; José & Hernanz 1998).
The codes have been parallelised using the MPICH2 implementation of the Message
Passing Interface (MPI) specification for the design of parallel applications using clusters of
distributed workstations. As an example, to execute a hydrodynamic simulation along 200k
time-steps, the SHIVA code requires (in its sequential, single-node version) about 147 hours
(6.1 days) to complete when using a reduced nuclear network with 324 isotopes and 1392
nuclear reactions, and 688 hours (28.6 days) when using a network with 606 nuclides and
3551 nuclear reactions for the same number of time-steps.
The post-processing nucleosynthesis code is a time-step loosely synchronous
application with a very small problem size (limited by the number of isotopes of the nuclear
network). As shown by the performance tests, this fact results in the worst possible scenario
for parallelisation; results show that the performance of the parallel application is much
worst than the sequential, 1-node version of the code. Our results show that it is therefore
not possible to parallelise efficiently a post-processing nucleosynthesis code, and efforts in
this regard should be avoided. On the contrary, the parallelised version of the SHIVA code
yields excellent performance results. A speed-up factor of 26 is achieved in a simulation with
a reduced network consisting of 324 isotopes and 1392 nuclear reactions when 42
processors are used in parallel to execute the application along 200k time-steps. On the
other hand, an excellent speed-up factor of 35 is accomplished in a simulation with a
reaction network up to 606 nuclides and 3551 nuclear reactions. Maximum speed-ups of
~41 and ~85 are predicted by the performance models when using 200 processors, for the
reduced and extended simulations respectively.
Our results will not only improve the quality of the simulations (and hence publications) in
terms of better numerical approaches, finer approximations, and a considerably shorter
time-to-publication, but also will allow taking advantage, if desired, of parallel
supercomputing facilities like the Mare Nostrum at the Supercomputing Centre in Barcelona
(BSC)
Mercado Central de Casma provincia de Ancash propuesta espacial enfocada al intercambio comercial potenciando la agroexportación
El presente proyecto se centra en la ciudad de Casma, ubicada en la Costa de la Región Ancash, cuenta con una dinámica propia, siendo un eje de integración comercial entre Chimbote, Huaraz y Huarmey, alberga una gran producción agropecuaria, convirtiéndose en una de las principales ciudades agroexportadoras del país, teniendo como principal actividad económica, la comercial. Sin embargo, su producción y los procesos económicos de intercambio, se ven limitados por falta de planificación, inversión y programas de desarrollo, por tal motivo para abordar la investigación partimos con el análisis de la actividad comercial y su actual pérdida de competitividad urbana en este sector económico, viendo cuál es la incidencia en su Planificación Urbana y desarrollo Socio-Económico.
La metodología de la investigación aplicada para el estudio es efectuada a través de un Enfoque Mixto, buscando cuantificar la información para generar proyecciones, vinculándolos con datos sin medición numérica, como la observación o descripción con el fin de obtener una “imagen” más completa del problema, teniendo como muestras de investigación, a nivel cualitativo, muestras teóricas, muestras de casos típicos y muestras confirmativas, y a nivel cuantitativo, muestras por racimos o clusters del comerciante - proveedor (oferta) , y muestras estratificadas de los distintos segmentos de la población (demanda).
Durante los últimos años la Ciudad de Casma, a pesar de tener como principal actividad económica, la comercial, ha perdido competitividad en este rubro debido a la insuficiencia y deterioro de sus instalaciones, los costos operativos,
prácticas comerciales ineficientes, escasa cultura empresarial, la ausencia de uso de tecnologías de información y comunicación, las malas condiciones de accesibilidad y el agotamiento de sus espacios para corresponder con nuevos requerimientos y demandas por parte de la población.
El proyecto tiene como objetivo potenciar el comercio, desarrollando un Nuevo Mercado Central, mostrando los productos de la ciudad, tanto nacional como internacionalmente, proponiendo una estructura que contenga un mercado minorista, que ocupe puestos y locales comerciales, un mercado mayorista donde se ubiquen los puestos y locales mayoristas, una zona de biohuertos, un área para ferias tecnológicas y auditorios (SUM), que permitan promover los productos que ofrece la ciudad en contexto, además de ellos sus respectivas áreas administrativas, recreativas y de sociabilización, generando un aporte urbano que añada valor al crecimiento de un ecosistema, cada vez más urgente en esta ciudad
Older adults and sport and physical activity professionals in Spain
Presence of monitors in physical activities and sports practiced by adults older than 64 years of age in Spain is analyzed in this research. The objective of this study is to determine the existence of monitors in relation to the sociodemographic features of older adults, the size of municipalities, the activities practiced, and the organizations where they are performed. The methodology used included a cross-sectional survey applied to a sample of older adults in Spain. The most relevant conclusions are that the presence of monitors in physical activities and sports practiced by older adults is dominant (63.8%), hence, their importance, and that the presence of monitors is higher for women (81.3%) than for men (37.5%). In addition, it is concluded that the bigger the municipality the higher the tendency to have more instructors. Regarding the type of activity, wide diversification is obtained; finally, there is a larger presence of monitors in sports entities (87.5%) and nursing homes (79.5%)
3D reconstruction of magnetization from dichroic soft X-ray transmission tomography
The development of magnetic nanostructures for applications in spintronics requires methods capable of visualizing their magnetization. Soft X‐ray magnetic imaging combined with circular magnetic dichroism allows nanostructures up to 100–300 nm in thickness to be probed with resolutions of 20–40 nm. Here a new iterative tomographic reconstruction method to extract the three‐dimensional magnetization configuration from tomographic projections is presented. The vector field is reconstructed by using a modified algebraic reconstruction approach based on solving a set of linear equations in an iterative manner. The application of this method is illustrated with two examples (magnetic nano‐disc and micro‐square heterostructure) along with comparison of error in reconstructions, and convergence of the algorithm
Portable Multi-Hypothesis Monte Carlo Localization for Mobile Robots
Self-localization is a fundamental capability that mobile robot navigation
systems integrate to move from one point to another using a map. Thus, any
enhancement in localization accuracy is crucial to perform delicate dexterity
tasks. This paper describes a new location that maintains several populations
of particles using the Monte Carlo Localization (MCL) algorithm, always
choosing the best one as the sytems's output. As novelties, our work includes a
multi-scale match matching algorithm to create new MCL populations and a metric
to determine the most reliable. It also contributes the state-of-the-art
implementations, enhancing recovery times from erroneous estimates or unknown
initial positions. The proposed method is evaluated in ROS2 in a module fully
integrated with Nav2 and compared with the current state-of-the-art Adaptive
ACML solution, obtaining good accuracy and recovery times.Comment: Submission for ICRA 202
Actividades Físicas Practicadas por las Mujeres Mayores en España
Esta investigación persigue profundizar en el conocimiento sobre las actividades físicas practicadas por las mujeres mayores en España y las posibles diferencias con los varones. El método desarrollado ha consistido en aplicar un cuestionario a una muestra aleatoria y representativa de la población de mujeres y varones mayores. Gran parte de estas mujeres mayores parecen tender a concentrar su práctica en programas de ejercicio físico o de actividades en el medio acuático. Sin embargo en los varones hay una mayor diversificación de las actividades realizadas.
This research chases to penetrate into the knowledge on the physical practised activities by the older women in Spain and the possible differences with the males. The developed method has consisted of applying a questionnaire to a random and representative sample of the population of women and older males. Great part of these older women they seem to tend to concentrate his practice in programs of physical exercise or activities in the aquatic way. Nevertheless in the males there is a major diversification of the realized activities
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