Search results for " MODELLI"
showing 10 items of 1472 documents
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…
Magnetic Stochastic Resonance in systems described by Dynamic Preisach Model
2008
Stochastic resonance (SR) is generally considered as an enhancement of the system response for certain finite values of the noise strength. In particular the signal to noise ratio (SNR) and the signal amplification show a maximum as a function of the noise intensity. This effect has been experimentally observed in many physical systems and also in magnetic systems. However, as far as magnetic systems are concerned, the dynamic features of the systems have been neglected and it has been assumed that the typical relaxation time is negligible. However this is clearly a rough approximation. In order to clarify this relation, in this paper we numerically study magnetic stochastic resonance in se…
Prosthetic modelling and simulation
2020
Abstract Modelling of physical systems can be divided into two categories: physical and mathematical modelling. Physical modelling is a process in which we construct tangible scale models that look very much like the real system. In the past century, consider the animal models that have significantly influenced the development of disease treatment and artificial joints. However, scale models require a great deal of time and resources to develop and there are limits to what can be learned from them. Mathematical or behavioural modelling is a more abstract system used for studying a research question that does not necessarily lend itself to physical modelling. In these models, the system is s…
Biological nitrogen and phosphorus removal in membrane bioreactors: model development and parameter estimation
2012
Membrane bioreactors (MBR) are being increasingly used for wastewater treatment. Mathematical modeling of MBR systems plays a key role in order to better explain their characteristics. Several MBR models have been presented in the literature focusing on different aspects: biological models, models which include soluble microbial products (SMP), physical models able to describe the membrane fouling and integrated models which couple the SMP models with the physical models. However, only a few integrated models have been developed which take into account the relationships between membrane fouling and biological processes. With respect to biological phosphorus removal in MBR systems, due to th…
Designing dynamic performance management systems to foster SME competitiveness according to a sustainable development perspective: empirical evidence…
2015
The role of performance management (PM) systems has become crucial for steering small-medium enterprises (SMEs) to successfully compete during the ongoing critical economic transition. To improve decision-maker strategic learning processes, traditional PM frameworks need to be combined with system dynamics (SD) modelling. This paper shows how to design and use a dynamic performance management (DPM) approach to assess and support SMEs competitiveness according to a sustainable development perspective. The emerging framework is applied to a real case of an Italian small business to analyse the empirical effectiveness of the approach hereby suggested.
Supporting start-up business model design through system dynamics modelling
2017
Purpose The purpose of this paper is to explore how system dynamics (SD) modelling can provide a methodological support to business model (BM) design with the intent to better communicate business strategy and manage performance. Design/methodology/approach After a literature review of the field and an analysis of the strengths and limitations of conventional BM frameworks, the paper illustrates and discusses an approach that combines such a framework with SD modelling. A single-case study design was selected to explore the implications and limitations of using this combined approach to business modelling. Findings The methodological support provided by SD to BM design may effectively impr…
Combining system dynamics modelling and management control systems to support strategic learning processes in SMEs: a Dynamic Performance Management …
2015
Traditional management control systems, mainly centred on accounting-based measures, are widely recognized as useful tools to support Small and Medium Enterprises (SMEs) managers and entrepreneurs in steering business development. However, due to the increasing turbulence and dynamic complexity that characterize today’s competitive arenas, such systems need to be combined with simulation-based methodologies in order to improve entrepreneurial learning processes and, as a result, better detect possible crisis symptoms and weak signals of change—emerging from the business environment—to promptly react. Therefore, the aim of this paper is to show how a combination of traditional management con…
MANUFACTURING E-MARKETPLACES: INNOVATIVE TOOLS FOR THE EXTENDED ENTERPRISE
2005
This Chapter introduces the research carried out under the research program titled “Distributed process and production planning in manufacturing enterprise networks” and funded by the Italian Ministry of Education, University and Research (MIUR) under the program PRIN2001. The research program aimed at developing an innovative concept of neutral linear e-marketplace able to support manufacturing enterprises networks in transactional, information sharing and exchange and collaborative relationship. The Chapter discusses the needs of innovative tools for supporting the new paradigm of the “extended enterprise” showing how the e-marketplace concept, when specific added value services are desig…
Exploring Process-Modelling Practice: Towards a Conceptual Model
2008
Despite the importance of process modelling for business process management and related tasks, there are few theories and empirical studies of process-modelling practice available that can serve as the basis for understanding and improving this important practice. To contribute to the development of better theory, this paper proposes a model of process modelling practice, focussing on the relations between process modelling purpose, process modelling process, model artefact, process modelling outcome as well as initial and eventual modelling and process maturity. The proposed model is based on the existing literature and validated in a study of 34 Norwegian process-modelling projects. Resul…
Modelling the transient behaviour of a MED-TVC plant for coupling with CSP
2015
In this paper a dynamic model for the MED-TVC process has been developed and valided by a comparison with data from a real plant situated in Trapani, Italy, composed by 12 effects with parallel-feed configuration and equipped with a medium-pressure steam vapour ejector.