Search results for "Simulation."
showing 10 items of 4779 documents
Structural verification and manufacturing procedures of the cooling system, for DEMO divertor target (OVT)
2019
The paper presents the design activities and testing plan of a vertical target mock-up, developed within the pre-conceptual design phase for DEMO Work Package DIV-1 “Divertor Cassette Design and Integration” - EUROfusion Power Plant Physics & Technology (PPPT) program. Activities concerning the Divertor Outboard Vertical Target cooling mock-up are presented in term of CAD model, thermal-hydraulic numerical simulation, structural analysis, structural integrity verification and manufacturing procedure. Moreover, the mechanical dimensions of support systems for Plasma Facing Components (PFCs), manifold and diffuser have been analyzed in detail, in order to avoid structural fault during the tes…
Modelling biological and chemically induced precipitation of calcium phosphate in enhanced biological phosphorus removal systems
2011
The biologically induced precipitation processes can be important in wastewater treatment, in particular treating raw wastewater with high calcium concentration combined with Enhanced Biological Phosphorus Removal. Currently, there is little information and experience in modelling jointly biological and chemical processes. This paper presents a calcium phosphate precipitation model and its inclusion in the Activated Sludge Model No 2d (ASM2d). The proposed precipitation model considers that aqueous phase reactions quickly achieve the chemical equilibrium and that aqueous-solid change is kinetically governed. The model was calibrated using data from four experiments in a Sequencing Batch Rea…
On the influence of curvature and torsion on turbulence in helically coiled pipes
2014
Turbulent flow and heat transfer in helically coiled pipes at Ret=400 was investigated by DNS using finite volume grids with up to 2.36×10^7 nodes. Two curvatures (0.1 and 0.3) and two torsions (0 and 0.3) were considered. The flow was fully developed hydrodynamically and thermally. The central discretization scheme was adopted for diffusion and advection terms, and the second order backward Euler scheme for time advancement. The grid spacing in wall units was ~3 radially, 7.5 circumferentially and 20 axially. The time step was equal to one viscous wall unit and simulations were typically protracted for 8000 time steps, the last 4000 of which were used to compute statistics. The results sho…
CFD Modelling of the Demister in the Multi Stage Flash Desalination plant
2011
Abstract Demisters are used to remove entrained brine droplets from flashed off vapor within the flashing stages of the multi stage flash desalination process (MSF). This is necessary to prevent accumulation of brine droplets on the outside surface of the condenser tubes and contamination of the desalinated water. The aim of this work is to design a new demister with lower pressure drop and unaffected separation efficiency which can be later installed in the flashing stages of the MSF plant and causes reduction in the required heat transfer area. In this work the demister performance is predicted as a function of design (wire diameter), and operating parameters (stage temperature). This obj…
Investigation of Inspiratory Pressure-Volume Curves on Mechanically Ventilated Patients Using Least Square Polynomial Fit
1988
Abstract An on-line method for the registration of pressure volume 1 oops TrT mechanically ventilated patients was developed using a personal computer with analog/digital interface. A third order polynomial function was fitted to the measured inspiratory pressure volume pairs. The significance of the fitting procedure was calculated using regression ANOVA. The inflection point of the pressure-volume curve was determinated by calculating the root of the second derivative of the polynomial. The method was teseted on 20 patients without major pulmonary dysfunction and on 6 patients with severe ARDS.
An evaluation of the environmental factors for supply chain strategy decisions using grey systems and composite indicators
2020
[EN] The purpose of this work is to assess the importance of environmental factors in a supply chain with four partners as a preliminary step to select the competitive strategies and objectives. To achieve this purpose, a real case study was carried out in a footwear supply chain, in which two approaches were used: the grey system theory and uncertainty analysis tools for composite indicators. In order to validate both approaches, a seven-phase research methodology was developed and applied to our case study. In addition, the priorization of environmental factors was calculated individually for each partner. The results allow managers to establish the competitive strategy that best suits th…
Aprendizaje de los fundamentos de la probabilidad apoyado en las TICs
2012
La red puede utilizarse como una herramienta docente más en Estadística, ya que en ella se puede acceder a numerosos recursos que pueden incorporarse a la docencia. En este artículo se describe un proyecto de integración de las denominadas simulaciones interactivas en una de las ramas de la Estadística en las que se pueden emplear: la probabilidad. El uso de estos recursos permite al alumno aprender de su propia experiencia y visualizar los conceptos estadísticos, lo que contribuye a mejorar su proceso de aprendizaje.
Modeling Marginalization: Emergence, Social Physics, and Social Ethics of Bullying
2020
In this paper, we outline the construction and initial simulation experiment results of the Marginalization model (MARG). We experiment under different group parameters because the theoretical paradigm we follow views bullying as a result of social processes. Our primary research question explores the possibility of bullying emergence as agents select interaction partners in a university setting. Based on the simulated process, our results take indications of the stress of marginalization in a student group as a proxy for emer-gent marginalization. MARG simulates two types of interactions between pairs of students: forced and hang-out interactions. In the latter, students decide whether to …
A Hybrid Model for an E-learning System Which Develops Metacognitive Skills at Students
2013
One of the goals of academic education is to train students in view of acquiring metacognitive skills, thus becoming self-regulated learners prepared for for lifelong learning. The research in this area has proved that metacognition can be taught and learned and that self-regulation behavior can be guided and constrained by the features of the learning environment. In order to become an educational environment, attractive and at the same time efficient for the students and which would enable students to develop their metacognitive skills, the e-learning system needs continuous improvments. This paper presents a hybrid model of an e-learning system, MEM - Metacognitive E-learning system Mode…
Overcoming managers’ myopic decisions in a waste collection company
2019
Purpose The purpose of this paper is to show how the changing interrelationships between fleet management, human resources and outsourcer capacity areas are likely to counterbalance managerial policies, thereby generating a performance decay. The use of system dynamics modelling in a waste collection company offered an effective contribution to support decision makers to overcoming myopic decisions. Design/methodology/approach Literature review and a case study analysis (including interviews with company actors and data gathering) offered the basis to build a system dynamics model. The model built was then used to run simulations sessions to assess alternative investments decisions. Findin…