Negative archaeology. The archaeological borders of the present

[ES] La arqueología está tratando de redefinir su relación con los objetos. Este cambio ocurre al tiempo en que Occidente atraviesa una nueva expansión de la sociedad de consumo, que confirma su ruptura definitiva con la generación que protagonizó el éxodo rural de mediados de s.XX. En este trabajo se plantea una revisión de las condiciones que permiten ahondar en esa ruptura y que determinan a su vez nuestra relación con la materialidad. Para ello se parte de una reconsideración de la relación pasado/presente y de las dinámicas que marcan esa diferencia. Nos encontramos en un momento en el que se está cambiando la experiencia del tiempo y con ella, la integridad del objeto arqueológico. Con el nombre de Arqueología Negativa se trata de explorar la frontera que determina la producción del pasado en un presente ocupado en homogeneizar cualquier tipo de diferencia. La arqueología es una disciplina única para desactivar ese proceso, o al menos para atestiguar las dinámicas a las que parecen destinarse los objetos. Para ello, se presenta el concepto de obsolescencia como un intento de nombrar el problema.[EN] Nowadays, archaeology is trying to redefine its relation with objects. This change is taking place at the same time as the West is breaking once and for all with the generation who did the rural exodus in the mid of the twentieth century. The present paper proposes a revision of the conditions that allow us to both define this rupture and at the same time determine our affinity with materiality. This is done through a reconsideration of the relation between the past and the present and the dynamics marking this difference. We are situated in a moment when the experience of time is shifting and thus so is the integrity of archaeological objects. Under the name of Negative Archaeology, the border between past and present is explored. This border determines the creation of the past in a present which intends to homogenise changes. Archaeology is a unique discipline which could prevent this process, or at least bear witness to the dynamics to which objects seem to be subjected. Obscolescence is introduced as a concept in an attempt to name the aforementioned problem.Peer Reviewe

Negative Archaeology. The Archaeological Borders of the Present

La arqueología está tratando de redefinir su relación con los objetos. Este cambio ocurre al tiempo en que Occidente atraviesa una nueva expansión de la sociedad de consumo, que confirma su ruptura definitiva con la generación que protagonizó el éxodo rural de mediados de s.XX. En este trabajo se plantea una revisión de las condiciones que permiten ahondar en esa ruptura y que determinan a su vez nuestra relación con la materialidad. Para ello se parte de una reconsideración de la relación pasado/presente y de las dinámicas que marcan esa diferencia. Nos encontramos en un momento en el que se está cambiando la experiencia del tiempo y con ella, la integridad del objeto arqueológico. Con el nombre de Arqueología Negativa se trata de explorar la frontera que determina la producción del pasado en un presente ocupado en homogeneizar cualquier tipo de diferencia. La arqueología es una disciplina única para desactivar ese proceso, o al menos para atestiguar las dinámicas a las que parecen destinarse los objetos. Para ello, se presenta el concepto de obsolescencia como un intento de nombrar el problema.Nowadays, archaeology is trying to redefine its relation with objects. This change is taking place at the same time as the West is breaking once and for all with the generation who did the rural exodus in the mid of the twentieth century. The present paper proposes a revision of the conditions that allow us to both define this rupture and at the same time determine our affinity with materiality. This is done through a reconsideration of the relation between the past and the present and the dynamics marking this difference. We are situated in a moment when the experience of time is shifting and thus so is the integrity of archaeological objects. Under the name of Negative Archaeology, the border between past and present is explored. This border determines the creation of the past in a present which intends to homogenise changes. Archaeology is a unique discipline which could prevent this process, or at least bear witness to the dynamics to which objects seem to be subjected. Obscolescence is introduced as a concept in an attempt to name the aforementioned problem

Determinants of job satisfaction: A European comparison of sel femployed and paid employees

Job satisfaction of self-employed and paid-employed workers is analyzed using the European Community Household Panel for the EU-15 covering the years 1994-2001. We distinguish between two types of job satisfaction, i.e. job satisfaction in terms of type of work and job satisfaction in terms of job security. Findings from our generalized ordered logit regressions indicate that self-employed individuals as compared to paid employees are more likely to be satisfied with their present jobs in terms of type of work and less likely to be satisfied in terms of job security. The findings also provide many insights into the determinants of the two types of job satisfaction for both the self-employed and paid employees.

Bike desk una propuesta de intervención para mejorar el nivel de actividad física y el rendimiento cognitivo en escolares de Educación Primaria

The aim of this study was to analyze the effect of 5 weeks of interactive pedaling during classes on physical fitness, school skills and creativity in primary school children. A total of 89 children (age range = 10-12 years) participated in this study, although due to the COVID-19 pandemic only 37 students could be considered for the analysis of the results. The students were randomly assigned to two groups, experimental group (EG) and control group (CG). The GE performed a moderate to vigorous intensity cycling program with cognitive engagement for 5 weeks, 4 days a week. Physical fitness, school skills and creativity were assessed. No significant differences were found between groups in terms of creativity. The CG experienced significant improvements in numeracy and total ASD. In addition, both groups showed significant improvements in the horizontal jump test. In conclusion, the implementation of pedal machines does not interfere with the academic performance of schoolchildren and can therefore be an effective means of improving students' physical activity levels.El objetivo de este estudio fue analizar el efecto de 5 semanas de pedaleo interactivo durante las clases en la condición física, aptitudes escolares y creatividad en niños de Educación Primaria. Un total de 89 niños (rango de edad = 10-12 años) participaron en este estudio, aunque debido a la pandemia del COVID-19 solo 37 alumnos se pudieron considerar para el análisis de los resultados. Los estudiantes fueron asignados al azar a dos grupos, grupo experimental (GE) y grupo de control (GC). El GE realizó un programa de pedaleo de intensidad moderada a vigorosa con compromiso cognitivo durante 5 semanas, 4 días a la semana. Se evaluaron la aptitud física, las aptitudes escolares y la creatividad. No se encontraron diferencias significativas entre los grupos en cuanto a creatividad se refiere. El GC experimentó mejoras significativas en el cálculo y el total TEA. Además, ambos grupos mostraron mejoras significativas en el test del salto horizontal. En conclusión, la implementación de pedaleadores no interfiere con el rendimiento académico de los escolares por lo que puede ser un medio efectivo para la mejora de los niveles de actividad física del alumnado

Experimental analysis of thermal storage tank configurationin a solar cooling installation with an absorption chiller

The use of air conditioning systems in Spanish dwellings is gaining popularity, as the installed units grows by 0,8 million per year. The most popular air conditioning system today is the vapor-compression cycle. This kind of system consumes a considerable amount of electric energy as it incorporates a mechanical compressor in its cycle and utilizes refrigerants that can be dangerous to the environment. A solution to this kind of equipment can be found in Solar Facilities configured to produce cold water for air conditioning purposes by means of an absorption chiller. This kind of equipment can be driven by a heat input produced by the solar facility. This machine consumes a very low amount of electric energy and presents great advantages for the environment. Nevertheless, the need of a heat reservoir to operate in the afternoon hours, where solar radiation is not enough to drive the chiller, is indispensable in a solar facility. To serve this purpose, the introduction of a thermal storage tank has to be made. There are two basic internal configurations of a thermal storage tank in a solar cooling facility. These are Stratification and Well-mixed configuration. Experimental results show that for solar cooling applications, having a homogeneous mixture temperature in the thermal storage tank produce more daily cooling energy than in an stratified one, although the solar field efficiency is lower. This gives the facility more autonomy of operation in the afternoon, when the sun goes down and radiation is not enough for the application. Effects on the facility produced by Well-mixed configuration are: efficiency reduction on the solar collector’s field , 0,27, higher daily COP’s, 0,33, and extended solar cooling time of about two hours.Universidad Carlos III de Madrid - ITEA Research GroupPublicad

Wooden-based materials: Eco-friendly materials for direct mass spectrometric analysis and microextraction

Lignocellulosic materials have arisen as a sustainable alternative in microextraction techniques during the last 10 years. As they are natural materials, their use fits into some of the principles of Green Analytical Chemistry. Their inherent porosity, narrow shape, and rigidity permit their use in ambient ionization mass spectrometry techniques. In particular, the combination of wooden-based materials and direct analysis gives birth to the so-called wooden-tip electrospray ionization mass spectrometry technique. This approach has been used for the direct analysis of complex samples, and as a streamlined tool for fingerprint quality analysis. Also, wooden-based materials can be superficially modified to boost the interaction with target compounds, allowing their isolation from complex samples. This review describes the potential and applicability of direct analysis using lignocellulosic materials, as well as other alternatives related to their use in microextraction

Estudio granulométrico comparativo en suelo caolín amarillo usando la normatividad INVÍAS y un equipo de última generación

Trabajo de investigaciónEl trabajo de grado, presenta el análisis para el caolín amarillo, mediante ensayos de laboratorio tradicional y ensayos de última generación. Muestra los resultados obtenidos en un estudio comparativo de métodos para el análisis de suelos, con base en el material caolín amarillo, mostrando los pros y contras del uso del método del hidrómetro y del equipo de última tecnología Pario, en la determinación de materiales del suelo.INTRODUCCIÓN 1. GENERALIDADES 2. OBJETIVOS 3. JUSTIFICACIÓN 4. MARCO DE REFERENCIA 5. METODOLOGIA 7. MONTAJE DEL ENSAYO 8. RESULTADOS 9. HIDRÓMETRO vs PARIO 10.CONCLUSIONES 11.RECOMENDACIONES BIBLIOGRÁFICA ANEXOS BIBLIOGRAFÍA ANEXOSPregradoIngeniero Civi

COMPARISON BETWEEN ANALYTICAL AND NUMERICAL METHODS IN THE DETERMINATION OF THE DEFLECTION OF A SOLID PLATE

In the last decades, different methods have been developed for the analysis and design of structures. The objective of this work is to compare the effectiveness of the numerical methods with respect to the analytical method. For this, the deflection of a solid slab was determined, first with a uniformly distributed load, and then, with a uniform load plus an axial compression load, by the finite difference and finite element methods (STAAD-PRO). , compared to the analytical solution. The results show the comparison of the three methods, through tables and graphs for each of the load cases, in which it can be observed that the difference between the three is very small, when an adequate discretization is used

STRUCTURAL TYPOLOGY OF THE HISTORIC CENTER OF THE CITY OF SINCELEJO

The new achievements that have been reached in the field of structural design can be applied only to new constructions; but the existing structures are the representation, in a greater percentage, of the structural characteristics of the cities. This study seeks to know the Structural Typology of the downtown area of the City of Sincelejo, which represents an optimization mechanism for Seismic Risk studies.. As the main tool, the Geographic Information System (GIS) technology was used, since it facilitates the implementation of the methods to be used, the management of information, and above all, the visualization of the results. The data obtained in the statistical analysis are shown in tables and figures, where the different typological characteristics of the buildings in the area appear. &nbsp

SEISMIC VULNERABILITY OF A REINFORCED CONCRETE BUILDING USING THE CAPACITY SPECTRUM METHODOLOGY

The designs carried out, following the requirements of the Seismic Resistant Standards, should present low Vulnerability and be more reliable in the face of seismic threats different from that of the design; but recent seismic events have shown the opposite, so it is necessary to evaluate the Seismic Vulnerability of structures based on the control of the Dynamic response. In this study, the Seismic Vulnerability of a reinforced concrete framed building was determined against three levels of seismic threat (service, design and severe earthquakes), using the methodology proposed by ATC-40, or the Capacity Spectrum methodology through an analysis Pushover, which resulted in this building, has the capacity to withstand a severe earthquake (Aa =0.15g), although the first floor beams are in the range of collapse, so its reinforcement is recommended