Search results for "Model building"

Model building on the non-factorisable type IIA T6/(Z4×ΩR) orientifold

2016

We construct global semi-realistic supersymmetric models with intersecting D6-branes on the non-factorisable orientifold . The non-factorisable structure gives rise to differences compared to the factorisable case: additional conditions for the three-cycles to be Lagrangian and extra constraints on the wrapping numbers for building fractional cycles.

Using Group Model Building and System Dynamics Modeling in Health Care Quality Assessment

Introduction & Research Aim Drawing from previous research on performance management, arguing that measurement systems in the public sector sometimes lead to harmful outcomes (Bianchi, 2010, 2015; Bivona & Montemaggiore, 2010), the purpose of this study is to assess the long-term dynamic impact of “ESY-net” (i.e. the Greek public hospitals' national performance measurement system) on the quality of healthcare services. Methods As hospital quality is a quite broad and abstract concept, perceived differently by different stakeholders, we will take a systemic view (Meadows, 2008; Sterman, 1994) and use Group Model Building (GMB) (De Gooyert, 2016, 2018; De Gooyert, Honingh, & Van G…

A test of transferability for landslides susceptibility models under extreme climatic events: application to the Messina 2009 disaster

2014

A model building strategy is tested to assess the susceptibility for extreme climatic events driven shallow landslides. In fact, extreme climatic inputs such as storms typically are very local phenomena in the Mediterranean areas, so that with the exception of recently stricken areas, the landslide inventories which are required to train any stochastic model are actually unavailable. A solution is here proposed, consisting in training a susceptibility model in a source catchment, which was implemented by applying the binary logistic regression technique, and exporting its predicting function (selected predictors regressed coefficients) in a target catchment to predict its landslide distribu…

The Elusive Structure of Magadiite, Solved by 3D Electron Diffraction and Model Building

2021

In addition to a great swelling ability, layered silicates also allow the functionalization of their interlayer region to form various robust green materials that are used as CO2 adsorbents, drug c...

Comparison of different predictive models for nutrient estimation in a sequencing batch reactor for wastewater treatment

2006

Abstract In this paper different predictive models for nutrient estimation in a sequencing batch reactor (SBR) for wastewater treatment are compared: principal component regression (PCR), partial least squares (PLS), and artificial neural networks (ANNs). Two unfolding procedures were used: batch-wise and variable-wise. For the latter unfolding method, X and Y matrix augmentation with lagged variables were used in some models to incorporate process dynamics. The results have shown that batch-wise unfolding PLS models outperform the other approaches. The ANN models are good predictive models, but in this particular case-study, they do not outperform those multivariate projection models that …

Neutrinos, DUNE and the world best bound on CPT invariance

2017

CPT symmetry, the combination of Charge Conjugation, Parity and Time reversal, is a cornerstone of our model building strategy and therefore the repercussions of its potential violation will severely threaten the most extended tool we currently use to describe physics, i.e. local relativistic quantum fields. However, limits on its conservation from the Kaon system look indeed imposing. In this work we will show that neutrino oscillation experiments can improve this limit by several orders of magnitude and therefore are an ideal tool to explore the foundations of our approach to Nature. Strictly speaking testing CPT violation would require an explicit model for how CPT is broken and its effe…

Bilarge neutrino mixing and the Cabibbo angle

2012

Recent measurements of the neutrino mixing angles cast doubt on the validity of the so-far popular tri-bimaximal mixing ansatz. We propose a parametrization for the neutrino mixing matrix where the reactor angle seeds the large solar and atmospheric mixing angles, equal to each other in first approximation. We suggest such bi-large mixing pattern as a model building standard, realized when the leading order value of the reactor angle equals the Cabibbo angle.

Implications of the restoration of chiral symmetry in bag model building

1985

We analyze via a bag model description of hadron structure the consequences of having two fundamental scales in QCD, one associated with confinement and the other with chiral-symmetry restration. The main effect is that the exterior pion field becomes weaker and, therefore, we are able to reproduce the axial-vector coupling constant.

LHC-scale left-right symmetry and unification

2013

We construct a comprehensive list of nonsupersymmetric standard model extensions with a low-scale left-right (LR)-symmetric intermediate stage that may be obtained as simple low-energy effective theories within a class of renormalizable SO(10) grand unified theories. Unlike the traditional minimal LR models many of our example settings support a perfect gauge coupling unification even if the LR scale is in the LHC domain at a price of only (a few copies of) one or two types of extra fields pulled down to the TeV-scale ballpark. We discuss the main aspects of a potentially realistic model building conforming the basic constraints from the quark and lepton sector flavor structure, proton deca…

Why do Traditional Performance Management Systems in Healthcare not always lead to Improved Performance? Outlining the Unintended Consequences of the…

2021

Researchers all around the globe have not yet come to an end as regards the supposed positive impact of traditional performance management systems in healthcare, and some research has shown that, paradoxically, performance management policies do not always lead to improved hospital performance. Despite the extensive research identifying the “pitfalls” of the NPM reforms around Europe and the unintended consequences for hospital staff and patients, little is known about the mechanisms that caused those negative effects, which essentially creates a research gap worth investigating. This PhD study tries to address this gap and show why do traditional PM Systems in healthcare not always lead to…