Enfoques para la gestión del riesgo sistémico

En el contexto organizacional actual, que se caracteriza por ser hiper-conectado, cambiante, globalizado y cargado de incertidumbre, la capacidad de las organizaciones para identificar y tratar provechosamente el riesgo se hace necesaria e ineludible. Dicho más claro: gestionar adecuadamente el riesgo se convierte en un aspecto crítico para la perdurabilidad de las organizaciones. Más allá de las comprensiones tradicionales del riesgo, cuyo núcleo es el riesgo financiero, nuevas tendencias –más generales y abarcadoras– se han gestado en las últimas décadas. Una de la más destacada es la gestión del riesgo sistémico. Pese a este reconocimiento, sin embargo, siguen predominando los enfoques analítico-financieros, sobre todo en el ámbito latinoamericano. Este trabajo de grado pretende, por tanto, hacer un análisis sobre la gestión del riesgo sistémico e identificar las diferentes tendencias del riesgo y sus potencialidades de cara al ambiente organizacional actual.

Why labor income shares seem to be constant?

The common assumptions that labor income share does not change over time or across countries and that factor income shares are equal to the elasticity of output with respect to factors have had important implications for economic theory. However, there are various theoretical reasons why the elasticity of output with respect to reproducible factors should be correlated with the stage of development. In particular, the behavior of international trade and capital flows and the existence of factor saving innovations imply such a correlation. If this correlation exists and if factor income shares are equal to the elasticity of output with respect to factors then the labor income share must be negatively correlated with the stage of development. We propose an explanation for why labor income share has no correlation with income per capita: the existence of a labor intensive sector which produces non tradable goods.

Reconocimiento geofísico del deslizamiento de Rosiana (depresión de Tirajana, Gran Canaria)

The landslide of Rosiana is considered the largest slope movement amongst those known in historical times in Gran Canana, Canary Islands. It has been activated at least 4 times in the last century, and in the movement of 1956, when about 3.106 m3 of materials were involved, 250 people had to be evacuated and many buildings were destroyed. The present geological hazard has lead to specific studies of the phenomenon which, once characterised, can be used as a guide for the scientific and technical works that are to be made in this or similar areas. This paper wants to increase the knowledge about the unstable mass of Rosiana by using geophysical techniques based on the method of seismic by refraction. The geophysical measues have been interpreted with the aid of the available geomorphologic data, thus obtaining a first approximation to the geometry of the slope movements

Investigación geofísica de los paleovalles pleistocenos del NE de Cataluña: el ejemplo de la Riera de Tossa (Costa Brava meridional)

The geometry of Riera de Tossa (Costa Brava, Catalonia) Pleistocene paleovalley has been studied by two geophysical prospecting methods: vertical electric sounding (VES-DC) and seismic refraction. The results show the existence of a sudden slope change of the thalweg that permits to differentiate two sections where erosion processes operated in unequal intensity. Based on geological and geomorphological available data, it can be inferred that this slope rupture is caused by the litological control imposed by the alineation of resistant materials, which limited the headward erosion extend of the creek during the Upper Pleistocene

Contribución al estudio del proceso de doblado al aire de chapa. Modelo de predicción del ángulo de recuperación y del radio de doblado final

Modelo de predicción de la geometría final de una pieza de chapa, radio y ángulo de doblado final, producida mediante un proceso de doblado al aire.

Mirades turístiques a la ciutat. Anàlisi del comportament dels visitants del Barri Vell de Girona

Mirades Turístiques a la ciutat és un estudi sobre el comportament del turisme en les ciutats monumentals, a partir de l'experiència viscuda pels visitants del Barri Vell de Girona. Una recerca que ha pretès determinar, precisament, la forma com els visitants entren en contacte amb el patrimoni monumental de la ciutat medieval. A partir, d'identificar quins factors influeixen (i quins no) en el comportament dels turistes durant la seva visita, tant pel que fa referència als factors ambientals generals (la meteorologia, la congestió, la informació...) com els factors singulars de cada visitant. Per tal d'assolir aquests objectius, en hem plantejat una sèrie d'hipòtesis de treball: 1. Existeix una manera turística d'apropar-se al patrimoni que té les seves pròpies regles, les seves estructures específiques i en conseqüència la necessitat d'uns instruments de gestió particulars. 2. L'aproximació del turista al patrimoni monumental és el resultat de dues forces aparentment contradictòries. D'una banda, el turista tendeix a reproduir pautes de comportament socialment construïdes que prenen la forma d'un ritual. D'altra banda, més enllà d'aquest patró comú, cada visitant viu una experiència singular. Per tant, la relació amb el patrimoni és el resultat d'un subtil equilibri entre experiència i ritual. 3. El consum turístic del patrimoni depèn de la relació entre quatre factors. El primer, la imatge del lloc, és la projecció (sovint idealitzada) de l'espai de visita, una metàfora de la ciutat. El segon, el codi d'interpretació turístic , actua com una mena de ritual, un guió no escrit de la pràctica turística. En tercer lloc, el substrat material que són els components artístics, històrics o culturals de la destinació: la geometria del casc, les visuals, el pes de la història o el valor estètic de les peces condicionen, com és obvi, la mirada turística. Finalment, l'experiència està condicionada per la gestió (pública i privada) del turisme: informació, fluxos, interpretació... L'estudi s'ha sustentat en una metodologia inèdita basada en l'observació directa a partir del seguiment dels visitants durant els seus recorreguts. Hem observat el visitants i hem recollit la informació bàsica de la seva visita: l'itinerari, els monuments visitats, les actituds manifestades, els temps d'estada... Aquesta metodologia ha estat ja implementada en alguns estudis de públic de diversos museus. S'han recollit tres tipus de dades: dades relacionades amb els arcs (segment de carrer entre dues interseccions), dades relacionades amb els nodes (els elements d'interès) i dades relacionades amb el visitant. Les tres fonts estan unides per un identificador comú, que és el codi del turista. Això ens ha permès vincular les dades dels visitants amb el seu recorregut i la seva visita als monuments de la ciutat. Els resultats de l'estudi ens han permès identificar els factors que singularitzen l'apropament dels visitants al patrimoni i que el diferencien d'altres formes de relació o ús. És a dir, els factors que incideixen en el comportament dels visitants de Girona. Així mateix, hem pogut definir models d'itineraris amb una estructura interna molt compacta però molt diferents entre ells; que ens evidencien que, malgrat les regularitats detectades en les visites dels turistes de la ciutat, també existeixen elements diferencials en el seu comportament. Hem detectat quatre models de recorreguts urbans que hem anomenat: itinerari bàsic, comercial, complex i de les muralles, que a l'hora es poden subdividir en varies categories. Finalment, els estadístics multivariants ens han permès demostrar que la relació entre el turista i el patrimoni respon almenys a quatre formes de consum diferenciades, que hem anomenat "no turistes", "rituals", "interessats" i "erudits".

Environmental control for layers

Light patterns have less effect on numbers of eggs laid by current stocks than on those of forty years ago, but the principles have not changed. Ovarian activity is stimulated by increasing photoperiods and suppressed by decreasing photoperiods. The light pattern used during rearing can still have large effects on age at 50% lay, even for modern stocks. Early sexual maturity maximises egg numbers but gives smaller eggs. Late maturity maximises egg size at the expense of numbers. The relationship between egg output (g/hen d) and age at first egg is curvilinear, with maximum yield occurring in flocks maturing in about the centre of their potential range. Fancy patterns of increasing daylength after maturity are probably not justified. A flock held on a constant 14h day will lay as many eggs as one given step up lighting. Intermittent lighting saves about 5% of feed consumption with no loss of output, provided that the feed has adequate amino acid content to allow for the reduced feed intake. Producers with light-proof laying houses should be taking advantage of intermittent lighting. The recommended light intensity for laying houses is still 10 lx, although the physiological threshold for response to changes in photoperiod is closer to 2 lx. Very dim (0.05 lx) light filtering into blacked out houses will not stimulate the hypothalamic receptors responsible for photo-sexual responses, but may affect the bird's biological clock, which can alter its response to a constant short photoperiod. Feed intake shows a curvilinear dependence on environmental temperature. At temperatures below the panting threshold, performance can be maintained by adjusting the feed so as to maintain an adequate intake of critical amino acids. Above the panting threshold, the hen is unable to take in enough energy to maintain normal output. There is no dietary modification which can effectively offset this problem. Diurnally cycling temperatures result in feed intake and egg production equivalent to that observed under a constant temperature equal to the mean of the cycle. When the poultry house is cooler at night than by day, it helps to provide light so that the birds can feed during the cooler part of the cycle.

Nanospheres on a silver plate

A Viewpoint on: 'Surface Geometry of C60 on Ag(111)' H. I. Li, K. Pussi, K. J. Hanna, L.-L. Wang, D. D. Johnson, H.-P. Cheng, H. Shin, S. Curtarolo, W. Moritz, J. A. Smerdon, R. McGrath, and R. D. Diehl. . Published in Physical Review Letters 103, 056101 (2009) on July 27, 2009.

Integrating Hamiltonian systems defined on the Lie groups SO(4) and SO(1,3)

This paper examines optimal solutions of control systems with drift defined on the orthonormal frame bundle of particular Riemannian manifolds of constant curvature. The manifolds considered here are the space forms Euclidean space E³, the spheres S³ and the hyperboloids H³ with the corresponding frame bundles equal to the Euclidean group of motions SE(3), the rotation group SO(4) and the Lorentz group SO(1,3). The optimal controls of these systems are solved explicitly in terms of elliptic functions. In this paper, a geometric interpretation of the extremal solutions is given with particular emphasis to a singularity in the explicit solutions. Using a reduced form of the Casimir functions the geometry of these solutions is illustrated.

A helmet mounted display system with active gaze control for visual telepresence

The objective of a Visual Telepresence System is to provide the operator with a high fidelity image from a remote stereo camera pair linked to a pan/tilt device such that the operator may reorient the camera position by use of head movement. Systems such as these which utilise virtual reality style helmet mounted displays have a number of limitations. The geometry of the camera positions and of the displays is generally fixed and is most suitable only for viewing elements of a scene at a particular distance. To address such limitations, a prototype system has been developed where the geometry of the displays and cameras is dynamically controlled by the eye movement of the operator. This paper explores why it is necessary to actively adjust the display system as well as the cameras and justifies the use of mechanical adjustment of the displays as an alternative to adjustment by electronic or image processing methods. The electronic and mechanical design is described including optical arrangements and control algorithms. The performance and accuracy of the system is assessed with respect to eye movement.

Dynamic vergence telepresence system incorporating active gaze control

Visual Telepresence system which utilize virtual reality style helmet mounted displays have a number of limitations. The geometry of the camera positions and of the display is fixed and is most suitable only for viewing elements of a scene at a particular distance. In such a system, the operator's ability to gaze around without use of head movement is severely limited. A trade off must be made between a poor viewing resolution or a narrow width of viewing field. To address these limitations a prototype system where the geometry of the displays and cameras is dynamically controlled by the eye movement of the operator has been developed. This paper explores the reasons why is necessary to actively adjust both the display system and the cameras and furthermore justifies the use of mechanical adjustment of the displays as an alternative to adjustment by electronic or image processing methods. The electronic and mechanical design is described including optical arrangements and control algorithms, An assessment of the performance of the system against a fixed camera/display system when operators are assigned basic tasks involving depth and distance/size perception. The sensitivity to variations in transient performance of the display and camera vergence is also assessed.

Toeplitz operators with distributional symbols on Bergman spaces

We study the boundedness and compactness of Toeplitz operators Ta on Bergman spaces , 1 < p < ∞. The novelty is that we allow distributional symbols. It turns out that the belonging of the symbol to a weighted Sobolev space of negative order is sufficient for the boundedness of Ta. We show the natural relation of the hyperbolic geometry of the disc and the order of the distribution. A corresponding sufficient condition for the compactness is also derived.

Capturing meaning construction in financial disclosure

Our study takes as its motivation common concerns across a variety of disciplines regarding an understanding of the linguistic, rhetorical and argumentative functions of the narrative aspects of financial disclosures, however with one significant alteration. This is that we do not restrict our investigation to the textual aspects but also consider the discursive nature of numbers. Numbers and narratives are simply alternative, and complementary, media to be used in disclosure, and many of the linguistic, and all of the rhetorical and argumentative, considerations apply to both, and need to be addressed and analysed. For complete version of the "long abstract" see attached full text pdf or the link in "Related URLs" field.

Sparse density estimation on the multinomial manifold

A new sparse kernel density estimator is introduced based on the minimum integrated square error criterion for the finite mixture model. Since the constraint on the mixing coefficients of the finite mixture model is on the multinomial manifold, we use the well-known Riemannian trust-region (RTR) algorithm for solving this problem. The first- and second-order Riemannian geometry of the multinomial manifold are derived and utilized in the RTR algorithm. Numerical examples are employed to demonstrate that the proposed approach is effective in constructing sparse kernel density estimators with an accuracy competitive with those of existing kernel density estimators.

Preliminary ethnoarchaeological research on modern animal husbandry in Bestansur, Iraqi Kurdistan: integrating animal, plant and environmental data

This paper presents preliminary results from an ethnoarchaeological study of animal husbandry in the modern village of Bestansur, situated in the lower Zagros Mountains of Iraqi Kurdistan. This research explores how modern families use and manage their livestock within the local landscape and identifies traces of this use. The aim is to provide the groundwork for future archaeological investigations focusing on the nearby Neolithic site of Bestansur. This is based on the premise that modern behaviours can suggest testable patterns for past practices within the same functional and ecological domains. Semi-structured interviews conducted with villagers from several households provided large amounts of information on modern behaviours that helped direct data collection, and which also illustrate notable shifts in practices and use of the local landscape over time. Strontium isotope analysis of modern plant material demonstrates that a measurable variation exists between the alluvial floodplain and the lower foothills, while analysis of modern dung samples shows clear variation between sheep/goat and cow dung, in terms of numbers of faecal spherulites. These results are specific to the local environment of Bestansur and can be used for evaluating and contextualising archaeological evidence as well as providing modern reference material for comparative purposes.