Rammed Earth Construction: A Proposal for a Statistical Quality Control in the Execution Process

Unlike other common contemporary construction materials such as concrete, mortars, or fired clay bricks, which are widely supported by international standards and regulations, building with rammed earth is barely regulated. Furthermore, its quality control is usually problematic, which regularly encourages the rejection of this technique. In the literature, many authors have suggested ways to safely build a rammed earth wall, but only a few of them have delved into its quality control before and during the construction process. This paper introduces a preliminary methodology and establishes unified criteria, based in a statistical analysis, for both the production and the quality control of this constructive technique in cases dealing with both samples and walls

Análisis de políticas públicas de suelo y agua en la región del Maule en el marco de la evaluación ambiental estratégica

110 p.Para determinar el estado de conservación de los recursos productivos silvoagropecuarios de suelo y agua utilizados en la Región del Maule, se realiza una Evaluación Ambiental Estratégica de las políticas públicas aplicadas, usando la metodología OCDE. El análisis indica un importante deterioro de estos recursos porque los programas gubernamentales de gestión de ellos no son suficientes para preservarlos y/o recuperarlos. Si no se toman medidas correctivas, se espera que la degradación genere un importante efecto negativo sobre la economía de la Región del Maule. Estos impactos irían por el lado de reducción de productividad por erosión de suelo o por reducción de agua para riego. Se propone la consideración de instrumentos de gestión ambiental complementarios a los programas públicos actualmente aplicados./SUMMARY:To determine the state of conservation of soil and water resources used in the Maule Region, we conducted a Strategic Environmental Assessment of public policies applied, using the OECD methodology. The analysis indicates a significant deterioration of the resources because government programs management are not sufficient to preserve and/or back. If corrective measures are not taken, it is expected that the degradation generates a significant negative effect on the economy of the region of Maule. These impacts would go by the side of productivity by reducing soil erosion or by reducing irrigation water. It is proposed that consideration of environmental management tools to complement public programs currently used

Perspectivas economicas del cultivo de las leguminosas en la comuna de Curepto.

116 p.El presente trabajo de investigación se orienta a establecer las perspectivas económicas del cultivo de las Leguminosas en la comuna de Curepto en un entorno de mercados globalizados. Para abordar el estudio, se analizan. utilizando técnicas estadísticas. factures relevantes 4tre caracterizan, en el país. tanto la Demanda (evolución del consumo per capita) coma la Oferta (Estructura productiva campesina y puntos de equilibrio). Considerando un contexto de mercados globalizados, se examinan las tendencias de consumo mundial de leguminosas a objeto de establecer proyectar las perspectivas comerciales de estos productos Finalmente, se concluye respecto de las posibilidades competitivas. en mercados globalizados, del cultivo de leguminosas en la comuna de Curepto

Influence of process parameters and initial microstructure on the oxidation resistance of Ti48Al2Cr2Nb coating obtained by laser metal deposition

[EN] Ti6Al4V have been the most important and versatile titanium alloys currently used, due to their excellent combination of low density and good mechanical properties, despite their application temperature being limited to up to 300 °C. In this work, a Ti6Al4V sheet was coated with a Ti48Al2Cr2Nb alloy by laser cladding process, with the process parameters resulting in laser-specific energy densities of 70, 80, 90 and 180 J/mm2, laser power between 600 and 900W and scanning speed of 100 to 300 mm/min. In order to analyze the oxidation resistance at elevated temperature, isothermal oxidation tests were carried out at 800 °C for 5, 10, 25, 50, 100 and 150 h in static air. The oxidized samples were characterized by optical microscopy (OM), scanning electron microscopy (SEM), field emission microscopy (FESEM) with energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD) analysis. Two groups of coatings with similar microstructures were obtained, and their influence on the formation of thermally oxidized growth layers was studied. From the isothermal oxidation tests, it was observed that the Ti48Al2Cr2Nb coatings have good resistance to oxidation in air at 800 °C in comparison with the Ti6Al4V substrate by obtaining layers of oxides up to 12 ¿m thick after 150 h of oxidation. The structure of the oxide layers is complex and comprises the growth of successive layers from the outer surface of the coating. The effect of the microstructure of the coating on the density of the oxide layer formed was evaluated.The authors would like to thank the Ministerio de Ciencia e Innovacion of the Spanish Government for their financial support through research project MAT2011-28492-C03 and the Generalitat Valenciana through grant ACOMP/2014/151.Zambrano Carrullo, JC.; Pereira Falcón, JC.; Amigó, V. (2019). Influence of process parameters and initial microstructure on the oxidation resistance of Ti48Al2Cr2Nb coating obtained by laser metal deposition. Surface and Coatings Technology. 358:114-124. https://doi.org/10.1016/j.surfcoat.2018.11.015S11412435

Validez del Penn State Worry Questionnaire-11 en Colombia y equivalencia factorial a través de género y muestras clínicas y no clínicas

The Penn State Worry Questionnaire (PSWQ) is the gold standard measure of the unspecific worry that characterizes generalized anxiety disorder. This study aims to explore the validity of the PSWQ in Colombia and its measurement invariance across gender and clinical and nonclinical participants. An abbreviated, 11-item version of the PSWQ by Sandín, Chorot, Valiente, and Lostao (2009) was used because the negatively worded items have shown to be problematic for Spanish speakers. Additionally, research has suggested that the negatively worded items of the PSWQ lack of practical utility. The PSWQ-11 was administered to a total of 1045 participants, including a sample of nonclinical participants (N = 710) and a sample of clinical participants (N = 335). The internal consistency of the PSWQ-11 across samples was excellent. The one-factor model showed an acceptable fit to the data. Metric and scalar invariance were observed across gender and clinical and nonclinical samples. In conclusion, the PSWQ-11 seems to be a valid measure of GAD-related worry in Colombia, whereas data on factorial equivalence data warrant the comparison of scores across gender and clinical and nonclinical samples.El Penn State Worry Questionnaire (PSWQ) es la medida principal de la preocupación inespecífica que caracteriza al trastorno de ansiedad generalizada (TAG). Este estudio explora la validez del PSWQ en Colombia y su invarianza de medida entre género y participantes clínicos y no clínicos. Se utilizó la versión abreviada de 11 ítems de PSWQ propuesta por Sandín, Chorot, Valiente y Lostao (2009) porque los ítems redactados negativamente han mostrado ser problemáticos para los hispanohablantes. Adicionalmente, la investigación ha sugerido que los ítems redactados en negativa carecen de utilidad práctica. El PSWQ-11 se administró a un total de 1045 participantes, incluyendo una muestra de participantes no clínicos (N = 710) y una muestra de participantes clínicos (N = 335). La consistencia interna del PSWQ-11 a través de muestras fue excelente. El modelo de un factor mostró un ajuste aceptable a los datos. Se observó invarianza métrica y escalar a través de género y muestras clínicas y no clínicas. En conclusión, el PSWQ-11 parece ser una medida válida de la preocupación tipo TAG, mientras que los datos sobre equivalencia factorial permiten la comparación de puntuaciones a través de género y participantes clínicos y no clínicos

Decision system based on neural networks to optimize the energy efficiency of a petrochemical plant

The energy efficiency of industrial plants is an important issue in any type of business but particularly in the chemical industry. Not only is it important in order to reduce costs, but also it is necessary even more as a means of reducing the amount of fuel that gets wasted, thereby improving productivity, ensuring better product quality, and generally increasing profits. This article describes a decision system developed for optimizing the energy efficiency of a petrochemical plant. The system has been developed after a data mining process of the parameters registered in the past. The designed system carries out an optimization process of the energy efficiency of the plant based on a combined algorithm that uses the following for obtaining a solution: On the one hand, the energy efficiency of the operation points occurred in the past and, on the other hand, a module of two neural networks to obtain new interpolated operation points. Besides, the work includes a previous discriminant analysis of the variables of the plant in order to select the parameters most important in the plant and to study the behavior of the energy efficiency index. This study also helped ensure an optimal training of the neural networks. The robustness of the system as well as its satisfactory results in the testing process (an average rise in the energy efficiency of around 7%, reaching, in some cases, up to 45%) have encouraged a consulting company (ALIATIS) to implement and to integrate the decision system as a pilot software in an SCADA

Cochlear Implant in Single-Sided Deafness Children and Adults

Binaural hearing in humans ensures our effective communication as it improves the sound localization, the speech understanding in noise, the spatial awareness, the listening easiness, and the development of spoken language. The majority of the literature on patients with single-sided deafness and cochlear implantation involves adult patients; the cochlear implant is a viable and cost-effective treatment option for this population. So in this chapter, we will emphasize the importance of early treatment of unilateral hearing loss in the pediatric age and the emerging indication of the cochlear implant as a treatment

Some advances in the research on Lie algebras

The main goal of this poster, which is written in the form of a survey and tries to show some aspects of the research of authors on Lie algebras, is to pay homage to the memory of Pilar Pisón Casares, who was firstly teacher of some of them and later colleague of all of them during different stages of her stay as a member of the Departamento de Algebra, Computación, Geometría y Topología de la Universidad de Sevilla

Risk Factors for Working Pregnant Women and Potential Adverse Consequences of Exposure: A Systematic Review

Objective: To assess the risk factors perceived as stressors by pregnant women in the work environment and the possible adverse consequences of such exposure for the normal development of pregnancy. Methods: Systematic review, guided by the PRISMA guidelines, and using Pubmed, Web of Science, Dialnet, SciELO, and REDIB databases. Methodological quality was assessed using the critical appraisal tools for non-randomised studies of the Joanna Briggs Institute. Results: A total of 38 studies were included. The main risk factors found in the work environment of pregnant women were chemical, psychosocial, physical-ergonomicmechanical factors, and other work-related factors. The main adverse consequences of exposure to these factors include low birth weight, preterm birth, miscarriage, hypertension and pre-eclampsia, as well as various obstetric complications. Conclusion: During pregnancy, working conditions that are considered acceptable in normal situations may not be so during this stage due to the major changes that occur during pregnancy. Many obstetric effects may have an important impact in the mother’s psychological status; therefore, it is important to optimise working conditions during this stage and to reduce or eliminate possible risksFunding for open access charge: Foundation for Science and Technology, Portugal (FCT)