Qualitative modelling of credit scoring : a case study in banking

Several modelling procedures have been suggested in the literature that aim to help credit granting decisions. Most of these utilize statistical, operational research and artificial intelligence techniques to identify patterns among past applications, in order to enable a more well-informed assessment of risk as well as the automation of credit scoring. For some types of loans, we find that the modelling procedure must permit the consideration of qualitative expert judgements concerning the performance attractiveness of the applications. In this paper, we describe in detail the various steps taken to build such a model in the context of the banking sector, using the MACBETH interactive approach. The model addresses the scoring of medium and long term loans to firms, to enable the multicriteria assignment of each application to a category which may range from rejection to acceptance with different spreads.peer-reviewe

Comparative study of hydroxyapatite coatings obtained by Sol-Gel and electrophoresis on titanium sheets

A comparative study of two coating methods on titanium (Ti) substrates, sol-gel and electrophoresis processes, was performed. Before coating, two different surface treatments were employed. The hydroxyapatite (HA) powder were characterized by infrared spectroscopy (FTIR) and X-ray diffraction (XRD) while coated samples were examined by using scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). Both techniques seem to be suitable to coat Ti. A previous surface treatment on metallic titanium seems to be fundamental to enhance coat uniformity and adhesion that was estimated by the adhesive tape test. The decrease in calcination temperature did not affect the coating adhesion.The authors thank the financial support of CAPES, CNPq, FAPERJ, and the cooperative project between CNPq/Brasil and MES/Cuba.Peer reviewe

Fiber Post Etching with Hydrogen Peroxide: Effect of Concentration and Application Time

AbstractIntroductionEtching is necessary to expose the fibers and enable both mechanical and chemical bonding of the resin core to the fiber post. This study evaluated the effect of concentration and application time of hydrogen peroxide on the surface topography and bond strength of glass fiber posts to resin cores.MethodsFiber posts were etched with 24% or 50% hydrogen peroxide for 1, 5, or 10 min (n = 10). Posts without any treatment were used as a control. After etching, the posts were silanated and adhesive resin was applied. The posts were positioned into a mold to allow a self-cured resin core to be inserted. The post/resin assembly was serially sectioned into five beams that were subjected to a tensile bond strength test. Data were subjected to two-way ANOVA and Tukey test (α = 0.05). The surface topography was analyzed using scanning electronic microscopy.ResultsNon-etched post presents a relatively smooth surface without fiber exposure. Application of hydrogen peroxide increased the surface roughness and exposed the fibers. All experimental conditions yielded similar bond strength values that were higher than those obtained in the control group.ConclusionBoth 24% and 50% hydrogen peroxide exposure increased the bond strength of resin to the posts, irrespective of the application time

The influence of noise emitted by vehicles on pedestrian crossing decision-making: a study in a virtual environment

When crossing a road, pedestrians must detect traffic, combine data coming from different perceptual modalities, evaluate the time envelope for safely cross the street, and monitor the position of oncoming vehicles to perform corrective actions if needed. This study analyzed the influence of noise emitted by vehicles, or its absence, on pedestrians’ crossing decision-making. Experiments were performed in a virtual environment using two road scenarios. Participants were presented with stimuli of approaching vehicles that varied regarding speed, movement patterns, and auditory condition: one concerning the approaching of an electric vehicle, another regarding the approaching of a gasoline combustion vehicle, and, finally, a condition regarding the absence of auditory cues. Participants were tasked with indicating the moment when they decided to cross the street. The results show that, despite the noise variations caused by the type of vehicle and its speed pattern, the participants’ decision to cross was mostly based on vehicle distance. When a vehicle approaches the crosswalk from a short distance and with no occlusion to the pedestrian’s visibility, the sound does not seem to influence the pedestrians’ crossing decision-making.The authors acknowledge the support of the research project: Nutraceutica come supporto nutrizionale nel paziente oncologico, CUP: B83D18000140007. E.B. Souto acknowledges the sponsorship of the projects M-ERA-NET-0004/2015-PAIRED and UIDB/04469/2020 (strategic fund), receiving support from the Portuguese Science and Technology Foundation, Ministry of Science and Education (FCT/MEC) through national funds, and co-financed by FEDER, under the Partnership Agreement PT2020

Materials Outgassing Rate Decay in Vacuum at Isothermal Conditions

As a laboratory for scientific research, the International Space Station has been in Low Earth Orbit for nearly 20 years and is expected to be on-orbit for another 10 years. The ISS has been maintaining a relatively pristine contamination environment for science payloads. Materials outgassing induced contamination is currently the dominant source for sensitive surfaces on ISS and modeling the outgassing rate decay over a 20 to 30 year period is challenging. Materials outgassing is described herein as a diffusion-reaction process using ASTM E 1559 rate data. The observation of -1/2 (diffusion) or non-integers (reaction limited) as rate decay exponents for common ISS materials indicate classical reaction kinetics is unsatisfactory in modeling materials outgassing. Non-randomness of reactant concentrations at the interface is the source of this deviation from classical reaction kinetics. A diffusion limited decay was adopted as the result of the correlation of the contaminant layer thicknesses on returned ISS hardware, the existence of high outgassing silicone exhibiting near diffusion limited decay, and the confirmation of non-depleted material after ten years in the Low Earth Orbit.Keywords: Materials Outgassing, ASTM E 1559, Reaction Kinetics, Diffusion, Space Environments Effects, Contaminatio

Portfolio robustness evaluation: a case study in the electricity sector

Managers continually face the task of allocating resources to projects when there is not enough money to fund them all. Portfolio Robustness Evaluation (PROBE) is a multicriteria decision support system developed to help managers to perform that difficult task. This paper presents a PROBE model, developed for an electricity distribution company, to select the best portfolio of projects, subject to budget constraints for different types of projects and various organisational units in multiple time periods. Projects requiring large-scale investments are analysed separately from the small-scale projects. The robustness of the selected portfolio of large-scale projects is analysed in an iterative process where broader uncertainty ranges are considered for the values of the projects, and also when an environmental impact criterion is added to the evaluation model. First published online: 14 Sep 201

International Space Station External Contamination Environment for Space Science Utilization

The International Space Station (ISS) is the largest and most complex onorbit platform for space science utilization in low Earth orbit. Multiple sites for external payloads, with exposure to the associated natural and induced environments, are available to support a variety of space science utilization objectives. Contamination is one of the induced environments that can impact performance, mission success and science utilization on the vehicle. The ISS has been designed, built and integrated with strict contamination requirements to provide low levels of induced contamination on external payload assets. This paper addresses the ISS induced contamination environment at attached payload sites, both at the requirements level as well as measurements made on returned hardware, and contamination forecasting maps being generated to support external payload topology studies and science utilization

Metabolic engineering of Saccharomyces cerevisiae for the production of top value chemicals from biorefinery carbohydrates

The implementation of biorefineries for a cost-effective and sustainable production of energy and chemicals from renewable carbon sources plays a fundamental role in the transition to a circular economy. The US Department of Energy identified a group of key target compounds that can be produced from biorefinery carbohydrates. In 2010, this list was revised and included organic acids (lactic, succinic, levulinic and 3-hydroxypropionic acids), sugar alcohols (xylitol and sorbitol), furans and derivatives (hydroxymethylfurfural, furfural and furandicarboxylic acid), biohydrocarbons (isoprene), and glycerol and its derivatives. The use of substrates like lignocellulosic biomass that impose harsh culture conditions drives the quest for the selection of suitable robust microorganisms. The yeast Saccharomyces cerevisiae, widely utilized in industrial processes, has been extensively engineered to produce high-value chemicals. For its robustness, ease of handling, genetic toolbox and fitness in an industrial context, S. cerevisiae is an ideal platform for the founding of sustainable bioprocesses. Taking these into account, this review focuses on metabolic engineering strategies that have been applied to S. cerevisiae for converting renewable resources into the previously identified chemical targets. The heterogeneity of each chemical and its manufacturing process leads to inevitable differences between the development stages of each process. Currently, 8 of 11 of these top value chemicals have been already reported to be produced by recombinant S. cerevisiae. While some of them are still in an early proof-of-concept stage, others, like xylitol or lactic acid, are already being produced from lignocellulosic biomass. Furthermore, the constant advances in genome-editing tools, e.g. CRISPR/Cas9, coupled with the application of innovative process concepts such as consolidated bioprocessing, will contribute for the establishment of S. cerevisiae-based biorefineries.This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/ 04469/2020, the PhD grants (SFRH/BD/132717/2017 to SLB, SFRH/ BD/130739/2017 to CEC and SFRH/BD/146367/2019 to POS), the MIT-Portugal Program (Ph.D. Grant PD/BD/128247/2016 to JTC), BioTecNorte operation (NORTE-01-0145-FEDER-000004) and Biomass and Bioenergy Research Infrastructure (BBRI)- LISBOA-01-0145-FEDER- 022059 funded by the European Regional Development Fund (ERDF) under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio