A convergent expansion of the Airy's integral with incomplete Gamma functions

There are two main power series for the Airy functions, namely the Maclaurin and the asymptotic expansions. The former converges for all finite values of the complex variable, $z$, but it requires a large number of terms for large values of $|z|$, and the latter is a Poincar\'{e}-type expansion which is well-suited for such large values and where optimal truncation is possible. The asymptotic series of the Airy function shows a classical example of the Stokes phenomenon where a type of discontinuity occurs for the homonymous multipliers. A new series expansion is presented here that stems from the method of steepest descents, as can the asymptotic series, but which is convergent for all values of the complex variable. It originates in the integration of uniformly convergent power series representing the integrand of the Airy's integral in different sections of the integration path. The new series expansion is not a power series and instead relies on the calculation of complete and incomplete Gamma functions. In this sense, it is related to the Hadamard expansions. It is an alternative expansion to the two main aforementioned power series that also offers some insight into the transition zone for the Stokes' multipliers due to the splitting of the integration path. Unlike the Hadamard series, it relies on only two different expansions, separated by a branch point, one of which is centered at infinity. The interest of the new series expansion is mainly a theoretical one in a twofold way. First of all, it shows how to convert an asymptotic series into a convergent one, even if the rate of convergence may be slow for small values of $|z|$. Secondly, it sheds some light on the Stokes phenomenon for the Airy function by showing the transition of the integration paths at $\arg z = \pm 2 \pi/3$.Comment: 21 pages, 23 figures. Changes in version 2: i) Footnote 10 has been added, ii) Figure 5 has been added for a deeper analysis of the results, iii) Reference 15 has been added, iv) Typo: A $\pm$ was missing in $\arg z = \pm 2 \pi/3$ (abstract), v) Some font size changes and improved labelling in the figures Changes in version 3: minor edition change

A Gravity Approach to Assess the Effects of Association Agreements on Euromediterranean Trade of Fruits and Vegetables

The paper is intended to draw on a gravity methodology to assess the impact of EuroMediterranean Association Agreement on Fruit and Vegetable trade from Mediterranean Partner Countries (MPC) to the EU. The Association Agreements appear to be significant as an explanatory of both fruit and vegetables’ trade flows to the EU. However, while the impact of such arrangements has contributed to boost MPC’s horticultural exports, it has not been sufficient to compensate the export loss related to the nature of MPCs as third countries. MPCs may have obtained gains from the EuroMed Agrements but the Barcelona process is still far to achieve its initial goals, at least concerning crucial products for the MPCs’ export strategy. The presented approach supplies a method to monitor future developments in the EuroMediterranean process.agricultural trade; Euro-Mediterranean agreements; fruit and vegetables

Domain-adaptive deep network compression

Deep Neural Networks trained on large datasets can be easily transferred to new domains with far fewer labeled examples by a process called fine-tuning. This has the advantage that representations learned in the large source domain can be exploited on smaller target domains. However, networks designed to be optimal for the source task are often prohibitively large for the target task. In this work we address the compression of networks after domain transfer. We focus on compression algorithms based on low-rank matrix decomposition. Existing methods base compression solely on learned network weights and ignore the statistics of network activations. We show that domain transfer leads to large shifts in network activations and that it is desirable to take this into account when compressing. We demonstrate that considering activation statistics when compressing weights leads to a rank-constrained regression problem with a closed-form solution. Because our method takes into account the target domain, it can more optimally remove the redundancy in the weights. Experiments show that our Domain Adaptive Low Rank (DALR) method significantly outperforms existing low-rank compression techniques. With our approach, the fc6 layer of VGG19 can be compressed more than 4x more than using truncated SVD alone -- with only a minor or no loss in accuracy. When applied to domain-transferred networks it allows for compression down to only 5-20% of the original number of parameters with only a minor drop in performance.Comment: Accepted at ICCV 201

The coupling of motion and conductive heating of a gas by localized energy sources

This paper investigates the time evolution of the near-isobaric flow field produced in a gas after the sudden application of a constant heat flux from a localized energy source. The problems of plane, line, and point heat sources are all investigated, with a power law for the temperature dependence of the thermal conductivity, after reduction to a quasi-linear heat equation for the temperature. In the planar and spherical cases, the constant heat flux defines scales for the length and time, which are used to nondimensionalize the problem. Numerical integration is used to provide the evolution of the temperature and velocity, and limiting solutions corresponding to small and large rescaled times are obtained. In the axisymmetric case, due to the absence of characteristic length and time scales, the solution is seen to admit a self-similar description in terms of the nondimensional heat flux. Profiles of temperature and radial velocity are provided for different values of this parameter, and the asymptotic limits of both small and large heating rates are addressed separately. The analysis reveals, in particular, the existence of front solutions when the resulting temperatures become much larger than the initial temperature, as occurs for sufficiently large times for the planar source, for sufficiently small times for the point source, and for sufficiently large heating rates for the line source

Evaluación de los impactos ambientales en la construcción de un centro cultural en el distrito de Pataz, provincia de Pataz - La Libertad

El presente trabajo de investigación es el resultado de un trabajo paciente y efectivo, tuvo como objetivo Evaluar el Impacto Ambiental en la Construcción de un centro Cultural en la Localidad del Distrito de Pataz. Se emplean las siguientes técnicas de recolección de datos: fotografías, apuntes, entrevistas (a propietarios que trabajan en el sector y a los pobladores que viven en el sector. Resultados. Para la identificación y evaluación de los posibles impactos ambientales que se pueden suscitar en las etapas de construcción y operación del Proyecto sobre los componentes ambientales en el Área de Influencia del Proyecto, se han utilizado métodos de identificación, predicción y evaluación de impactos ambientales. La identificación, predicción y cuantificación de los impactos se desarrollarán sobre la base de los métodos utilizados comúnmente para este fin, considerando principalmente las acciones a realizar durante las actividades de construcción y operación del proyecto. En conclusión. Con la construcción del centro cultural en el Distrito de Pataz, la población podrá contar con instalaciones adecuadas para la educación de sus familias. El análisis de las etapas y partidas que conforman la ejecución del proyecto Evaluación de los Impactos Ambientales en la Construcción de un Centro Cultural en el Distrito de Pataz, se logró identificar los impactos ambientales generados en cada actividad. Se puede concluir que todos los impactos identificados en cada actividad son de carácter negativos. De esta maneria se puede concluir que se logró determinar que existen daños con gravedad: no relevante, leve y moderada. Así mismo los riesgos de estos impactos identificados se pudieron clasificar como riesgos leves, moderados y significativos, siendo estos últimos con mayor valoración en cuanto a peligrosida

Service work and subcontracting in the new economy: Call centres in Mexico City.

This dissertation analyses the subcontracting of front-line service work in the new economy. Its aim is to examine how workers' experiences and employment conditions are affected by how subcontractors respond to the challenges and problems of coordination and negotiation with client firms. In recent years, subcontracting has gained popularity as a mechanism to deal with the uncertainty of increasingly challenging business environments. According to mainstream business scholars and social scientists, intense competition, variations in demand and technical change have forced organizations to substitute hierarchical arrangements by market mediated transactions. Nonetheless, the practice of subcontracting also raises important concerns. Subcontracting might blur organizational boundaries, fragmenting employers' authority and affecting coordination between organizations. In other words, subcontracting might involve problems that, in practice, increase transaction costs and affect workers' experiences. This research is based on extensive information collected through 65 in-depth interviews with workers and managers concerning their work experiences in call centres in Mexico City. Call centres are often seen as a flag-ship industry of the new economy, rapidly growing and subject to constant pressures for cost reduction. The Mexican case is also relevant as it is characterized by a weak institutional setting where labour protection is low and business competition is largely unregulated. The findings of this research identify those managerial practices that can be more affected or associated with the difficulties of negotiation and coordination between subcontractors and client firms; narrowed job designs; customer segmentation; the use of contracts for services; supervision approach; union avoidance; the use of internal labour markets to secure management loyalty; and reinforcing social divisions in the workplace. These findings also suggest that a number of practices that were common in the old economy are still relevant in the organization of work in the twenty-first century