461 resultados para VACANCY


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Este artículo analiza la incidencia de la memoria colectiva en las identificaciones laborales del presente, a través del estudio de jóvenes trabajadores precarizados. Desarrolla un abordaje teórico sobre las identificaciones juveniles, la precarización y la memoria colectiva, cuya vinculación temática resulta poco frecuente en la Sociología del Trabajo. Buscando cubrir dicha área de vacancia, realizamos un estudio de caso centrado en jóvenes trabajadores precarizados que realizaron pasantías en el call center de un organismo público en el periodo 2008-2012. Desde un abordaje cualitativo analizamos los discursos de los pasantes como espacio de cristalización de sus formas identitarias. Como resultado encontramos que las condiciones de precarización laboral en que estos jóvenes se construían en trabajadores no condujeron a su naturalización, sino que por el contrario sus identificaciones estaban atravesadas por el imaginario de una sociedad salarial pasada, con estabilidades y seguridades laborales, que fue insumo de sus movilizaciones frente a la precarización

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Este artículo analiza la incidencia de la memoria colectiva en las identificaciones laborales del presente, a través del estudio de jóvenes trabajadores precarizados. Desarrolla un abordaje teórico sobre las identificaciones juveniles, la precarización y la memoria colectiva, cuya vinculación temática resulta poco frecuente en la Sociología del Trabajo. Buscando cubrir dicha área de vacancia, realizamos un estudio de caso centrado en jóvenes trabajadores precarizados que realizaron pasantías en el call center de un organismo público en el periodo 2008-2012. Desde un abordaje cualitativo analizamos los discursos de los pasantes como espacio de cristalización de sus formas identitarias. Como resultado encontramos que las condiciones de precarización laboral en que estos jóvenes se construían en trabajadores no condujeron a su naturalización, sino que por el contrario sus identificaciones estaban atravesadas por el imaginario de una sociedad salarial pasada, con estabilidades y seguridades laborales, que fue insumo de sus movilizaciones frente a la precarización

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Helium retention in irradiated tungsten leads to swelling, pore formation, sample exfoliation and embrittlement with deleterious consequences in many applications. In particular, the use of tungsten in future nuclear fusion plants is proposed due to its good refractory properties. However, serious concerns about tungsten survivability stems from the fact that it must withstand severe irradiation conditions. In magnetic fusion as well as in inertial fusion (particularly with direct drive targets), tungsten components will be exposed to low and high energy ion (helium) irradiation, respectively. A common feature is that the most detrimental situations will take place in pulsed mode, i.e., high flux irradiation. There is increasing evidence on a correlation between a high helium flux and an enhancement of detrimental effects on tungsten. Nevertheless, the nature of these effects is not well understood due to the subtleties imposed by the exact temperature profile evolution, ion energy, pulse duration, existence of impurities and simultaneous irradiation with other species. Physically based Kinetic Monte Carlo is the technique of choice to simulate the evolution of radiation-induced damage inside solids in large temporal and space scales. We have used the recently developed code MMonCa (Modular Monte Carlo simulator), presented in this conference for the first time, to study He retention (and in general defect evolution) in tungsten samples irradiated with high intensity helium pulses. The code simulates the interactions among a large variety of defects and impurities (He and C) during the irradiation stage and the subsequent annealing steps. In addition, it allows us to vary the sample temperature to follow the severe thermo-mechanical effects of the pulses. In this work we will describe the helium kinetics for different irradiation conditions. A competition is established between fast helium cluster migration and trapping at large defects, being the temperature a determinant factor. In fact, high temperatures (induced by the pulses) are responsible for large vacancy cluster formation and subsequent additional trapping with respect to low flux irradiation.

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We consider two intrinsic sources of noise in ultra-sensitive magnetic field sensors based on MgO magnetic tunnel junctions, coming both from 25 Mg nuclear spins (I = 5/2, 10% natural abundance) and S = 1 Mg-vacancies. While nuclear spins induce noise peaked in the MHz frequency range, the vacancies noise peaks in the GHz range. We find that the nuclear noise in submicron devices has a similar magnitude than the 1/f noise, while the vacancy-induced noise dominates in the GHz range. Interestingly, the noise spectrum under a finite magnetic field gradient may provide spatial information about the spins in the MgO layer.

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In this letter, Prince informs Holyoke of his desire to appeal the Board of Overseers' decision to dismiss him. Prince also asserts his belief that, until his appeal is considered, he should continue to perform his duties as Tutor and that the Corporation has no legal authority to fill a vacancy which does not exist.

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Performing Pedagogies was a week-long performance and exhibition series I organized that took place in Kingston, Ontario between March 15th - March 20th 2016. The motivation for this project came from a desire to explore performative modes of experiencing critical, embodied knowledge. The series featured five performances, a long distance collaboration between thirty-one Queen’s undergraduate students and a Vancouver artist-run free school (The School for Eventual Vacancy), a subsequent exhibition, a panel discussion, and a radical performance pedagogy workshop led by co-artistic director of the international performance art troupe, La Pocha Nostra. Artists featured included Golboo Amani, Basil AlZeri, Caitlin Chaisson, Justin Langlois, Saul Garcia-Lopez, Francisco-Fernando Granados, and Andrew Rabyniuk. By curating examples of performance art that variously incorporated embodied pedagogical interventions, I examined the processes of performance as pedagogy. Performing Pedagogies explored interventions into contemporary contours of neoliberal education paradigms through embodied encounters—fostering conversations about the meanings and limitations of knowledge dissemination and education today and posing questions about possibilities for radical pedagogies, embodied knowledge, and counter curricula.

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Performing Pedagogies was a week-long performance and exhibition series I organized that took place in Kingston, Ontario between March 15th - March 20th 2016. The motivation for this project came from a desire to explore performative modes of experiencing critical, embodied knowledge. The series featured five performances, a long distance collaboration between thirty-one Queen’s undergraduate students and a Vancouver artist-run free school (The School for Eventual Vacancy), a subsequent exhibition, a panel discussion, and a radical performance pedagogy workshop led by co-artistic director of the international performance art troupe, La Pocha Nostra. Artists featured included Golboo Amani, Basil AlZeri, Caitlin Chaisson, Justin Langlois, Saul Garcia-Lopez, Francisco-Fernando Granados, and Andrew Rabyniuk. By curating examples of performance art that variously incorporated embodied pedagogical interventions, I examined the processes of performance as pedagogy. Performing Pedagogies explored interventions into contemporary contours of neoliberal education paradigms through embodied encounters—fostering conversations about the meanings and limitations of knowledge dissemination and education today and posing questions about possibilities for radical pedagogies, embodied knowledge, and counter curricula.

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Measuring Job Openings: Evidence from Swedish Plant Level Data. In modern macroeconomic models “job openings'' are a key component. Thus, when taking these models to the data we need an empirical counterpart to the theoretical concept of job openings. To achieve this, the literature relies on job vacancies measured either in survey or register data. Insofar as this concept captures the concept of job openings well we should see a tight relationship between vacancies and subsequent hires on the micro level. To investigate this, I analyze a new data set of Swedish hires and job vacancies on the plant level covering the period 2001-2012. I find that vacancies contain little power in predicting hires over and above (i) whether the number of vacancies is positive and (ii) plant size. Building on this, I propose an alternative measure of job openings in the economy. This measure (i) better predicts hiring at the plant level and (ii) provides a better fitting aggregate matching function vis-à-vis the traditional vacancy measure. Firm Level Evidence from Two Vacancy Measures. Using firm level survey and register data for both Sweden and Denmark we show systematic mis-measurement in both vacancy measures. While the register-based measure on the aggregate constitutes a quarter of the survey-based measure, the latter is not a super-set of the former. To obtain the full set of unique vacancies in these two databases, the number of survey vacancies should be multiplied by approximately 1.2. Importantly, this adjustment factor varies over time and across firm characteristics. Our findings have implications for both the search-matching literature and policy analysis based on vacancy measures: observed changes in vacancies can be an outcome of changes in mis-measurement, and are not necessarily changes in the actual number of vacancies. Swedish Unemployment Dynamics. We study the contribution of different labor market flows to business cycle variations in unemployment in the context of a dual labor market. To this end, we develop a decomposition method that allows for a distinction between permanent and temporary employment. We also allow for slow convergence to steady state which is characteristic of European labor markets. We apply the method to a new Swedish data set covering the period 1987-2012 and show that the relative contributions of inflows and outflows to/from unemployment are roughly 60/30. The remaining 10\% are due to flows not involving unemployment. Even though temporary contracts only cover 9-11\% of the working age population, variations in flows involving temporary contracts account for 44\% of the variation in unemployment. We also show that the importance of flows involving temporary contracts is likely to be understated if one does not account for non-steady state dynamics. The New Keynesian Transmission Mechanism: A Heterogeneous-Agent Perspective. We argue that a 2-agent version of the standard New Keynesian model---where a ``worker'' receives only labor income and a “capitalist'' only profit income---offers insights about how income inequality affects the monetary transmission mechanism. Under rigid prices, monetary policy affects the distribution of consumption, but it has no effect on output as workers choose not to change their hours worked in response to wage movements. In the corresponding representative-agent model, in contrast, hours do rise after a monetary policy loosening due to a wealth effect on labor supply: profits fall, thus reducing the representative worker's income. If wages are rigid too, however, the monetary transmission mechanism is active and resembles that in the corresponding representative-agent model. Here, workers are not on their labor supply curve and hence respond passively to demand, and profits are procyclical.

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The electrical and optical characteristics of a cylindrical alumina insulator (94% Al203) have been measured under ultra-high vacuum (P < 10-8 mBar) conditions. A high-resolution CCD camera was used to make real-time optical recordings of DC prebreakdown luminescence from the ceramic, under conditions where DC current magnitudes were limited to less than 50μA. Two concentric metallized rings formed a pair of co-axial electrodes, on the end-face of the alumina tube; a third 'transparent' electrode was employed to study the effect of an orthogonal electric field upon the radial conduction processes within the metallized alumina specimen. The wavelength-spectra of the emitted light was quantified using a high-speed scanning monochromator and photo-multiplier tube detector. Concurrent electrical measurements were made alongside the recording of optical-emission images. An observed time-dependence of the photon-emission is correlated with a time-variation observed in the DC current-voltage characteristics of the alumina. Optical images were also recorded of pulsed-field surface-flashover events on the alumina ceramic. An intensified high-speed video technique provided 1ms frames of surface-flashover events, whilst 100ns frames were achieved using an ultra high-speed fast-framing camera. By coupling this fast-frame camera to a digital storage oscilloscope, it was possible to establish a temporal correlation between the application of a voltage-pulse to the ceramic and the evolution of photonic emissions from the subsequent surface-flashover event. The electro-optical DC prebreakdown characteristics of the alumina are discussed in terms of solid-state photon-emission processes, that are believed to arise from radiative electron-recombination at vacancy-defects and substitutional impurity centres within the surface-layers of the ceramic. The physical nature of vacancy-defects within an alumina dielectric is extensively explored, with a particular focus placed upon the trapped electron energy-levels that may be present at these defect centres. Finally, consideration is given to the practical application of alumina in the trigger-ceramic of a sealed triggered vacuum gap (TVG) switch. For this purpose, a physical model describing the initiation of electrical breakdown within the TVG regime is proposed, and is based upon the explosive destabilisation of trapped charge within the alumina ceramic, triggering the onset of surface-flashover along the insulator. In the main-gap prebreakdown phase, it is suggested that the electrical-breakdown of the TVG is initiated by the low-field 'stripping' of prebreakdown electrons from vacancy-defects in the ceramic under the influence of an orthogonal main-gap electric field.

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The crystal structure of natural magnetite has been investigated on the basis of previously published X-ray intensity data and a newly acquired, more extensive data base. Both investigations show that the structure does not conform to the centrosymmetrical space group Fd3m, as is normally assumed, but the non-centrosymmetrical space group F43m. The structure refinement provides values for the atom positions, anisotropic thermal parameters and bond lengths. A study of Friedel related pairs of X-ray intensities shows that Friedel's law is violated in magnetite, further confirming that the space group is non-centrosymmetrical. It was found that the octahedral site cations in magnetite do not occupy special positions at the centres of the octahedral interstices as they should under the space group Fd3m, but are displaced along <111 > directions leading to F43m symmetry. A mechanism is known for the origin of these displacements and the likelihood of similar displacements occurring in other natural and synthetic spinels is discussed. The crystal structure of a natural titanomaghemite was determined by a combination of X-ray diffraction and Mõssbauer spectroscopy. This was confirmed as possessing a primitive cubic Bravais lattice with the space group P4332 and the structural formula: Fe3+.0.96 0 0.04 [Fe2+0.23 Fe3+0.99 Ti4+0.42 0 0.37 ] 042 - where 0 represents a cation vacancy. As the above formula shows, there are cation vacancies on both tetrahedral arrl octahedral sites, the majority being restricted to octahedral sltes. No tetrahedral site Fe2+ or Ti4+ was observed. Values for the atom positions, anisotropic thermal parameters and bond lengths have been determined for this particular specimen.

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The effect of stress on vacancy cluster configurations in silicon is examined using molecular dynamics. At zero pressure, the shape and stability of the vacancy clusters agrees with previous atomistic results. When stress is applied the orientation of small planar clusters changes to reduce the strain energy. The preferred orientation for the vacancy clusters under stress agrees with the experimentally observed orientations of hydrogen platelets in the high stress regions of hydrogen implanted silicon. These results suggest a theory for hydrogen platelet formation. © 2005 The American Physical Society.

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A study has been made of serrated yielding in two commercial Al-Zn-Mg alloys in the as-quenched condition. The different serration types produced in the two alloys and the shear failure mechanism observed in both notched-bend and tensile testing are related to the mechanisms of dynamic strain ageing occurring during the test. An estimate of 19.7 kJ/mole for the activation energy for exchange of a solute atom and a vacancy in Al-6.2 wt% Zn, 2.5 wt% Mg has been made. © 1981.

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For many y ears, the federal government policy is to use project for in order to speed up the work for decreasing the elementary education deficit vacancy . In Natal municipality the schoolhouses for children, from 0 to 6 years of age are denom inated Muinicipality Centre for Elementary Education. The federal government provides capital for the news edifications by the program of government named PROINFÂNCIA. This program embraces three types of projects. Type “A” must be furnished by the interes ted municipality and approved by Education and Cultura Ministry. The type “B” is standard plan with capability to 120 schoolchildren in full - time or 240 in two turns and ground plot measuring 40 x 70m and the “type C” also a standart projects to 60 schoolc hildren in full - time or 120 in two turns and ground plot measuring 35 x 45m. Sometimes , due to scarcity of bigger ground plot s is the “type C” instead of “type B”, referring to offering vacancies. In this meaning, this study intend s to present the draft - project to elementary schoolhouse, modulated and flexible, emphasizing the children needs . Therefore, it was studied concept, school architecture, construction technology, reference study and visiting to MCEE Fernanda Jales (PROINFÂNC IA “tipo B”). However, the proposal synthesizes the draft - project by module, implanting in its totality or in parts, according to its necessity and lot cha racteristic.

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The thesis presents the results of research that addresses the performance of selective horizontal partitioning to promote Fire Safety in Buildings - FSB. Horizontal partitioning is a passive protection measure, settable in the early stages of the design process and controlled by the architect. However, there is a frequent reconfiguration of the rooms in academic buildings to adjust them for the space demand. Thus, large classrooms could turn into two or more smaller rooms, for example. Regardless when the subdivision occurs in the design phase or during the occupation of the building, the regulations just ensures the compartimentation of the room if all fireguard devices are present in the room. Knowing the fire's first minutes are the most important for life protection, we defend the hypothesis that a kind of partitioning ignored by regulatory standards is able to favoring the building vacancy and occupants rescue, for promote the room’s smoke exhaust. The performance of the selective horizontal partitioning due different blend of openings for smoke outlet was simulated on CFD software. The results indicate that selective horizontal partitioning is able to promote an upper smoke free layer and delay the indoor temperature growth.

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The thesis presents the results of research that addresses the performance of selective horizontal partitioning to promote Fire Safety in Buildings - FSB. Horizontal partitioning is a passive protection measure, settable in the early stages of the design process and controlled by the architect. However, there is a frequent reconfiguration of the rooms in academic buildings to adjust them for the space demand. Thus, large classrooms could turn into two or more smaller rooms, for example. Regardless when the subdivision occurs in the design phase or during the occupation of the building, the regulations just ensures the compartimentation of the room if all fireguard devices are present in the room. Knowing the fire's first minutes are the most important for life protection, we defend the hypothesis that a kind of partitioning ignored by regulatory standards is able to favoring the building vacancy and occupants rescue, for promote the room’s smoke exhaust. The performance of the selective horizontal partitioning due different blend of openings for smoke outlet was simulated on CFD software. The results indicate that selective horizontal partitioning is able to promote an upper smoke free layer and delay the indoor temperature growth.