Search results for "1105"
showing 10 items of 459 documents
Optimization of the Surface Roughness Equation obtained by Al7136 End-Milling
2017
The aim of this paper is to optimize the regression equation of the surface roughness obtained by 7136 aluminium alloy machined by end-milling process. The surface roughness is dependent on certain process parameters, which can vary, causing in this way variations of the surface quality. The research method used in this paper is the experiment and the Taguchi design of experiment. The experiment was performed using an experimental stand, in which every step to get the purpose, is presented. The measurements were made using a portable surface roughness tester. In the first part of the paper the influence percentage of the involved parameters in the machining process, was determined. Then, a …
Experimental research regarding the study of surface quality of aluminum alloys processed through milling
2017
The aim of this paper is to present the necessary steps to conduct a design of experiment with application on the aluminum alloy surface quality obtained by end-milling process. The machined surface quality is influenced by the cutting process parameters, and especially by their variation. The research methods used in this paper are the Taguchi method - to determine the cutting parameters influence, on the surface quality, and the full factorial design of experiment to confirm the results obtained by Taguchi’s method and to determine the percentage of the parameters influence involved in the process.
SUSTAINABLE ARCHITECTURE: THE ECO-EFFICIENCY EARTH CONSTRUCTION
2017
The appropriate choice of building materials can contribute decisively to reduce the energy consumption of the building sector. The increasing worries for the environmental impact of construction materials is witnessed by a lot of studies The mentioned worries has brought again the attention towards natural materials. The use of more sustainable construction materials and construction techniques represent a major contribution to the eco-efficiency of the construction industry and thus to a more sustainable development. Within this frame the renewed interest for a natural material such as the rammed earth is included; the interest has been in continuous growth from the 80s till today. The ra…
La Responsabilidad Social de la Educación Superior como Bien Común. Concepto y desafíos
2018
Este artículo atiende al planteamiento de la Unesco de considerar como bien común a la Educación Superior, en un momento en que las Instituciones de Educación Superior están inmersas en procesos caracterizados por una progresiva mercantilización del conocimiento que condiciona el acceso a la financiación por posicionamiento en rankings internacionales, poniendo en riesgo el objeto de contribuir a un desarrollo sostenible en sus contextos. Mediante un particular análisis de aspectos relacionados con la Responsabilidad Social y la relación con los grupos de interés, se realiza una contribución a la reflexión teórica y a los desafíos para conceptualizar la Educación Superior como un bien común.
Responsabilidad Social Universitaria (RSU): Principios para una universidad sostenible, cooperativa y democrática desde el diagnóstico participativo …
2017
El presente estudio analiza los discursos bajo los cuales se reconoce el sentido de 'Responsabilidad Social Universitaria' concediendo la voz a uno de sus protagonistas, el alumnado, para emitir conclusiones sobre su visión y elevarlas a los y las responsables de la política universitaria. Para ello, se ha realizado una investigación con metodología cuantitativa y cualitativa sistematizada durante dos cursos académicos con 206 alumnos/as del grado de Educación Social de la Universidad de Valencia (España). El objetivo del estudio ha sido realizar un diagnóstico participativo sobre el estado de la cuestión de la RSU y el Desarrollo Sostenible basado en el cuestionario de Vallaeys, De la Cruz…
A person-environment-fit-model for temporary organizations - Antecedents for temporary working settings
2021
Abstract Projectification has led to the widespread use of temporary organizations (TOs) in many industries, but the various factors that determine successful work by employees in TOs are unexplored. We argue that organizations have different degrees of temporariness depending on the following five TO dimensions: temporal duration, nature of the task, team composition, hierarchy, and coordination. Considering the TO dimensions and varying degrees of temporariness, we propose a person-environment (P-E) fit model. The model comprises three levels – organizational-, group-, and job-oriented – and relates personal attributes to the TO dimensions. We contribute to theory by developing a set of p…
Mechanical and Thermal Properties of Insulating Sustainable Mortars with Ampelodesmos mauritanicus and Pennisetum setaceum Plants as Aggregates
2021
The use of natural fibers in cement composites is a widening research field as their application can enhance the mechanical and thermal behavior of cement mortars and limit their carbon footprint. In this paper, two different wild grasses, i.e., Ampelodesmos mauritanicus, also called diss, and Pennisetum setaceum, also known as crimson fountaingrass, are used as a source of natural aggregates for cement mortars. The main purpose is to assess the possibility of using the more invasive crimson fountaingrass in place of diss in cement-based vegetable concrete. The two plant fibers have been characterized by means of scanning electron microscopy (SEM), helium picnometry and thermogravimetric an…
Effect of Cu-Zn coated steel fibers on high temperature resistance of reactive powder concrete
2019
Abstract Even though many studies have reported about the impacts of shape, length and distribution of steel fiber reinforcement on global concrete properties, there is a lack of information about the influence of coating type of steel fibers on high temperature resistance of concrete. This paper describes the effect of Cu-Zn coated steel fibers on selected properties of reactive powder concrete (RPC) after exposure to elevated temperatures. The initial corrosion of zinc in Cu-Zn surface layer is found to be already activated by the alkaline environment of the fresh concrete. The RPC samples reinforced with Cu-Zn coated steel fibers are heated to 600 °C and 1000 °C, and the influence of the…
Teaching How to Write Essays in Secondary Education: Didactic Sequences Analysis
2021
[EN] The development of the writing expression competence, and in particular, the argumentative competence has awoken interest among the different educational levels. The essay has been studied from different pers-pectives in Secondary Education, however there are not any studies on how books teach the writing process at this level, where the mini-essay format is actually worked on more. Therefore, the main objective of this paper is to learn more about the examples of didactic sequences to teach how to write essays/mini-essays in textbooks of third and fourth year of Secondary Education. The methodology applied is the analysis of the qualitative content and the gathering of information fro…
The role of nanoparticles in decreased washout of underwater concrete
2019
Abstract The paper presents research results of the influence of SiO2 nanoparticles on the washout of underwater concrete and hardened concrete. Based on infrared spectroscopy (FTIR) and thermogravimetric (TGA) analyses of the applied anti-washout admixture (AWA), its chemical structure was determined. A beneficial effect of SiO2 nanoparticles on the reduction of the mix washout was demonstrated and the most probable reason for that phenomenon was given, taking into account the AWA chemical structure and its behaviour in the concrete mix environment. It was found that a dosing method of AWA and nanoparticles to the concrete influenced the washout.