Search results for "modelling."

Fuzzy modelling of HEART methodology: application in safety analyses of accidental exposure in irradiation plants

2009

The present paper refers to the obtained results by using Fuzzy Fault Tree analyses of accidental scenarios which entail the potential exposure of operators working in irradiation industrial plants. For these analyses the HEART methodology, a first generation of the Human Reliability Analysis method, has been employed to evaluate the probability of human erroneous actions. This technique has been modified by us on the basis of fuzzy set concept to more directly take into account the uncertainties of the so called error-promoting factors, on which the method is grounded. The results allow also to provide some recommendations on procedures and safety equipments to reduce the radiological expo…

Stochastic 0-dimensional Biogeochemical Flux Model: Effect of temperature fluctuations on the dynamics of the biogeochemical properties in a marine e…

2021

Abstract We present a new stochastic model, based on a 0-dimensional version of the well known biogeochemical flux model (BFM), which allows to take into account the temperature random fluctuations present in natural systems and therefore to describe more realistically the dynamics of real marine ecosystems. The study presents a detailed analysis of the effects of randomly varying temperature on the lower trophic levels of the food web and ocean biogeochemical processes. More in detail, the temperature is described as a stochastic process driven by an additive self-correlated Gaussian noise. Varying both correlation time and intensity of the noise source, the predominance of different plank…

Ability of software SWMM to simulate sewer smooth pressurization transient

2010

As a consequence of heavy rainfall events or network malfunctioning, filling of sewers (pressurization) and network overflowing may occur. Several models are commonly used to simulate floods in drainage networks and their results are usually thought to be reliable and robust. Actually, mathematical models based on the momentum equation appear to be more suitable in correctly simulating the pressurization moving jump but models based on the energy equation are much more popular because of their greater simplicity in comparison to the former ones. In this paper, on the basis of laboratory pipe tests, the ability of software SWMM (Storm Water Management Model, probably the most popular softwar…

SPH NUMERICAL MODELLING OF WAVE-STRUCTURE INTERACTION

The present thesis aims at contributing to a better understanding and modelling of flow driven by wave propagation approaching artificial or natural structures. From a physical point of view, a simplistic descrip- tion of the interaction of sea waves with a coastal structure can be given as the result of all processes felt by the waves which, propagating from offshore to nearshore, impact on the structure itself. Indeed, as sea waves approach a shore, the motion they generate deep down begins to interact with the sea bed. This slows the waves down and causes the crests in a series of waves to bunch up; this effect is called shoaling. The period of the waves does not change, but their height…

Differentiating Malignant from Benign Pigmented or Non-Pigmented Skin Tumours—A Pilot Study on 3D Hyperspectral Imaging of Complex Skin Surfaces and …

2022

Several optical imaging techniques have been developed to ease the burden of skin cancer disease on our health care system. Hyperspectral images can be used to identify biological tissues by their diffuse reflected spectra. In this second part of a three-phase pilot study, we used a novel hand-held SICSURFIS Spectral Imager with an adaptable field of view and target-wise selectable wavelength channels to provide detailed spectral and spatial data for lesions on complex surfaces. The hyperspectral images (33 wavelengths, 477–891 nm) provided photometric data through individually controlled illumination modules, enabling convolutional networks to utilise spectral, spatial, and skin-surface mo…

Prospects of territorial intelligence tool Catalyse according to governance

2013

Catalysis method has been developed since 1989 as a scientific tool for territorial intelligence and governance. It is currently undergoing major adjustments that are presented in this paper. Catalysis was immediately concerted as a tool for territorial stakeholders' cooperation and citizen participation in local initiatives . It allows a stakeholder partnership to confront the needs of a given population with resource inventory and indicators of a territory as to predict and assess the evolution of these elements. It mobilized for this purpose a set of basic project management and and evaluation techniques, survey processing , data analysis and spatial information. It includes tools for ac…

Modeling Changes for SHOIN(D) Ontologies: An Exhaustive Structural Model

2013

Ontology development starts with a rigorous ontological analysis that provides a conceptualization of the domain to model agreed by the community. An ontology, specified in a formal language, approximates the intended models of this conceptualization. It needs then to be revised and refined until an ontological commitment is found. Also ulterior updates, responding to changes in the domain and/or the conceptualization, are expected to occur throughout the ontology life cycle. To handle a consistent application of changes, a couple of ontology evolution methodologies have been proposed. Maintaining the structural consistency is one of the ontology evolution criteria. It implies modeling chan…

Improving efficiency and discharge power of acid-base flow battery via a bi-objective optimisation

2023

Modelling and optimization of a passive structural control design for a spar-type floating wind turbine

2014

Abstract Compared with fixed-bottom installation, deep water floating wind turbine has to undergo more severe structural loads due to extra degrees of freedom. Aiming for effective load reduction, this paper deals with the evaluation of a passive structural control design for a spar-type floating wind turbine, and the proposed strategy is to install a tuned mass damper (TMD) into the spar platform. Firstly, a mathematical model for wind turbine surge-heave-pitch motion is established based on the D’Alembert’s principle of inertial forces. Then, parameter estimation is performed by comparing the outputs from the proposed model and the state-of-the-art simulator. Further, different optimizati…

Engaged managers are not workaholics: Evidence from a longitudinal personcentered analysis

2013

El objetivo de este estudio longitudinal entre directivos finlandeses ( n = 463) fue doble: en primer lugar investigar la relación entre el engagement (E) y la adicción al trabajo (AT) mediante enfoques centrados en la persona y en la variable y, en segundo lugar, explorar si (y cómo) se relacionan las experiencias de engagement y la adicción al trabajo con el cambio de trabajo durante el período de estudio. El análisis centrado en las variables, basado en modelos de ecuaciones estructurales, mostró que los factores latentes del engagement y la adicción al mismo no correlacionan entre sí, lo que sugiere que son constructos independien- tes. Los análisis centrados en la persona indicaron cua…