Search results for "modelling"
showing 10 items of 1353 documents
Explaining the rising precariat in Spain
2020
[EN] Spanish GDP indicator figures recover while the risk of poverty has not stopped increasing since 2007 given the continuous austerity policies adopted by Governments, while labour and welfare conditions have worsened. A new phenomenon is emerging: the flattening of the Spanish middle class. This study proposes a model to quantify the number of individuals according to their level of precariousness in Spain. The model allows us to predict the behaviour of society in Spain given the mimetic nature of humans by constructing a discrete finite epidemiological model that classifies and quantifies the population in Spain according to its risk of precariousness. Our results show a rise in the p…
Developing a Life Cycle Management methodology for road pavements
2022
The necessity of implementing sustainability is a main challenge in our society and it is taking up also in civil engineering works sector, although the infrastructure field is still understanding how to make the Sustainability Assessment (SA) a common practice within the National Road Authorities (NRAs). This research aims at providing a specific methodology for the Life Cycle Management (LCM) of road pavements materials and activities, starting from the available ISO and EN standards, by using Life-Cycle based techniques and Multi-Criteria Decision Making (MCDM), with the aim of assessing performance under the three pillars of sustainability.
A school trip and three modelling tasks. A experience in a secondary classroom
2015
[EN] This paper describes an experimence conducted in a ninth grade classroom. Three modeling tasks have been designed both related with the organization of a school trip. The main objective is to obtain the aspects to be considered when we propose this kind of tasks. For this aim we will analyze the result of experience thought the student’s responses in order to identify and classify the difficulties encountered them
A Comprehensive Check of Usle-Based Soil Loss Prediction Models at the Sparacia (South Italy) Site
2020
At first, in this paper a general definition of the event rainfall-runoff erosivity factor for the USLE-based models, REFe = (QR)b1(EI30)b2, in which QR is the event runoff coefficient, EI30 is the single-storm erosion index and b1 and b2 are coefficients, was introduced. The rainfall-runoff erosivity factors of the USLE (b1 = 0, b2 = 1), USLE-M (b1 = b2 = 1), USLE-MB (b1 ≠ 1, b2 = 1), USLE-MR (b1 = 1, b2 ≠ 1), USLE-MM (b1 = b2 ≠ 1) and USLE-M2 (b1 ≠ b2 ≠ 1) can be defined using REFe. Then, the different expressions of REFe were simultaneously tested against a dataset of normalized bare plot soil losses, AeN, collected at the Sparacia (south Italy) site. As expected, the poorest AeN predict…
Comparison between energy balance and mass balance models for actual evapotranspiration assessment
2009
The assessment of the water needs for a specific crop has a fundamental importance in the management of water resources. The application of empirical models able to retrieve estimates of the actual evapotranspiration (ETa) to assess the need for water could give a valid tool for the planning of water supply, avoiding unnecessary water losses. In this context, two independent models for estimating actual evapotranspiration were compared. The first model is based on an energy balance and uses remotely sensed data and ancillary data from weather stations to assess the ETa. The second model also uses remotely sensed data and climatic data on a daily basis from a weather network. Field measureme…
Predicting the equilibrium bed slope in natural streams using a stochastic model for incipient sediment motion
2011
In this paper, a method to predict the equilibrium bed slope in natural streams based on the incipient motion criterion is proposed. The method is based on the criterion suggested by Gessler to simulate the grain size distribution of the armour coat using the concept of critical shear stress of a sediment mixture. In particular, a different expression of the probability for a single particle size to be part of the armour coat is firstly proposed; then, a simple two-steps criterion is suggested to estimate the safety factor required by the proposed approach. The method is applied in three different Italian regions (Calabria, Basilicata, and Tuscany) and required several field campaigns invol…
Pressure Retarded Osmosis: a Membrane Process for Environmental Sustainability
2016
Salinity Gradient Power (SGP) based on the controlled mixing between two solutions at different salinities is a viable alternative to produce power from renewable sources. Pressure Retarded Osmosis (PRO) is one of the most promising technologies proposed so far for the exploitation of such energy source. Apart from the typical source of salinity gradients, namely river water and seawater, more and more interest has been raised recently towards the use of non-conventional saline solutions. In this work, water originating from a sewage treatment plant is used as the dilute solution (feed solution), while brine exiting from a desalination plant is used as the concentrate (draw solution), thus …
Kindergarten teachers adjust their teaching practices in accordance with children's academic pre-skills
2011
This study examined the extent to which kindergarten children’s academic pre‐skills are associated with their teachers’ subsequent teaching practices. The pre‐skills in reading and math of 1268 children (655 boys, 613 girls) were measured in kindergarten in the fall. A pair of trained observers used the Classroom Assessment Scoring System instrument to observe 49 kindergarten teachers on their emotional support, classroom organisation and instructional support in kindergarten in the spring. The results of the multilevel modelling showed that low levels of academic pre‐skills in kindergarten classrooms in the fall predicted high classroom quality in the classrooms later on. The results sugge…
Factors behind low reading literacy achievement
2004
The initial results of the Programme for International Student Assessment (PISA) indicated that Finnish and Swedish students are among the best readers in all OECD countries. However, the literac ...
Upper Secondary School and University Level Students’ Perceptions of Extractions in Context: Experiences from a Simple Laboratory Experiment
2021
We discuss the pedagogical challenges associated with the current way of introducing extraction in upper secondary school chemistry education. These challenges were identified based on a survey of upper secondary school textbooks and verified through a questionnaire study. To address the identified challenges, we introduce a simple and effective extraction experiment which focuses on building a deeper conceptual understanding of extraction processes. The operationally simple extraction experiment and the accompanying questionnaire revealed that while students have several chemical misconceptions arising from the use of superficial everyday examples, they have all the necessary knowledge for…