Search results for "Bull"
showing 10 items of 345 documents
Familia, profesorado e iguales: claves para el apoyo a las víctimas de acoso escolar
2011
ResumenEl objetivo del presente estudio fue analizar las diferencias en ajuste psicológico en víctimas de acoso escolar en función de la calidad de sus relaciones con padres, profesores e iguales. En concreto, se compararon cuatro indicadores de ajuste psicológico (autoestima, ánimo depresivo, soledad y percepción de estrés) en víctimas con buena o mala comunicación con la madre, buena o mala comunicación con el padre, alta o baja percepción de ayuda del profesor, y alta o baja identificación con su grupo de iguales. La muestra inicial estuvo compuesta por 1795 adolescentes, entre 11 y 18 años (M=14.2, DT=1.68). Los resultados indicaron que las víctimas que mantenían mejores relaciones soci…
Weibull Model for Dynamic Pricing in e-Business
2011
As is the case with traditional markets, the sellers on the Internet do not usually know the demand functions of their customers. However, in such a digital environment, a seller can experiment different prices in order to maximize his profits. In this paper, we develop a dynamic pricing model to solve the pricing problem of a Web-store, where seller sets a fixed price and buyer either accepts or doesn’t buy. Frequent price changes occur due to current market conditions. The model is based on the two-parameter Weibull distribution (indexed by scale and shape parameters), which is used as the underlying distribution of a random variable X representing the amount of revenue received in the sp…
Indagini teoriche e sperimentali su dissipatori ad attrito per edifici in acciaio in zona sismica
2017
The present paper presents the results of experimental analyses carried out to study the behaviour of slotted bolted connections (SBC) as friction steel dampers. The devices consist of bolted joints with slotted holes, which can be used in both steel and RC framed structures or, alternatively, into beam-column and column-foundation joints. The most suitable configurations to increase friction are investigated utilizing steel S355J0 plates and class 10.9HV high-strength bolts, under controlled pre-load and considering different types of surface treatment. Experimental tests are carried out making use of a universal testing machine, which allows mak-ing displacement-controlled tests. Once the…
A family of weakest link models for fiber strength distribution
2007
It is well known that the most widely used distribution function for fiber tensile strength, the two-parameter Weibull distribution, does not always adequately describe the experimentally observed fiber strength scatter and the strength dependence on fiber length. To remedy this discrepancy, modifications of the Weibull distribution have been proposed that, while providing a good empirical fit to the strength data, sometimes lack the theoretical appeal of the weakest link models. We derive a family of weakest link models based on the assumption of a two-stage failure process incorporating explicitly the probabilities of flaw initiation and the fiber fracture due to the largest flaw (i.e. th…
Cybervictimización y cyberagresión en estudiantes universitarios : problemas emocionales y uso problemático de nuevas tecnologías
2018
Fil: Resett, Santiago. Pontificia Universidad Católica Argentina. Facultad Teresa de Ávila. Departamento de Humanidades; Argentina Fil: Resett, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Putallaz, Romina Paula. Universidad de Palermo; Argentina Resumen: La cybervictimización y la cybeagresión constituyen importantes factores de riesgo para la salud mental de los individuos ya que, por ejemplo, en algunos casos la cybervictimización puede conducir al suicidio de las víctimas. Si bien en la actualidad en la Argentina se ha prestado una notable atención a estas problemáticas, pocos estudios se han llevado a cabo en dicho país para determinar los correl…
Multiple morphological characters needed for field identification of cryptic long‐eared bat species around the Swiss Alps
2010
The identification of cryptic species may significantly change our view about their distribution, abundance, ecology and therefore conservation status. In the European Alps, molecular studies have revealed the existence of three sibling species of plecotine bats Plecotus auritus, Plecotus austriacus and, very recently, Plecotus macrobullaris. Knowledge of the ecological niche partitioning of cryptic species is a requisite to develop sound conservation policies. Yet, this requests the development of unambiguous identification methods easily applicable in the field. This study investigates the reliability of several morphological methods used for species recognition and proposes a new identif…
Is fiscal fatigue a threat to consolidation programmes?
2015
Building on a narrative approach to identify episodes of fiscal consolidation, data for a group of 17 industrial countries over the period 1978-2009 and continuous-time duration models, we find evidence suggesting that the likelihood of a fiscal consolidation ending increases over time, but only for programs that last less than six years. Additionally, fiscal consolidations tend to last longer in non-European than in European countries. Our results emphasize that chronic fiscal imbalances might lead to a vicious austerity cycle, while discipline in the behaviour of fiscal authorities is a means of achieving credible and shorter adjustment measures. Therefore, fiscal fatigue is likely to com…
The Legacy and the Tyranny of Time: Exit and Re-Entry of Sovereigns to International Capital Markets
2018
We use a novel continuous-time Weibull model (without and) with a change-point in the duration dependence parameter to investigate the duration of the exit and re-entry of sovereigns to international capital markets. Relying on annual data for a large panel of countries over the period 1970-2011, we find that, as the reputation of debtor countries as good (bad) borrowers solidifies over time, those episodes are more likely to end - i.e. the "legacy of time". Debtor countries can take advantage of the "benefit of doubt" of creditors during short exit spells. However, when exits are long and the reputation as a bad borrower emerges, no more "complacency" makes it more difficult for them to bo…
Dental implants in patients with oral mucosal alterations : an update
2010
Objective: To determine whether a series of diseases of the oral mucosa - Sjogren syndrome, ectodermal dysplasia, epidermolysis bullosa and lichen planus - reduce the survival rate of dental implants. Material and Method: A Medline search was carried out using the key words: "Sjogren syndrome", "ectodermal dysplasia", "epidermolysis bullosa", "lichen planus" and "dental implants", including those publications involving clinical series comprising more than one patient with the mentioned disorders and treated with dental implants, in the last 10 years. Results: The study included three articles involving patients with Sjogren syndrome subjected to dental implant treatment, representing a tota…
CYBERBULLYING AND NEW TECHNOLOGIES AN EDUCATIONAL PROJECT FOR EMOTIONAL ORIENTATION AND CYBERBULLYING PREVENTION
2019
Cyberbullying as a new form of bullying demands new coping strategies. As a result of new technology there has been a constant growth in the spread of harmful online behavior. The instant project “Cyberbullying and new technology”, which started from cooperation between school and university, was planned for pupils in the third year at “Leonardo Da Vinci” secondary school in Palermo. The project was started and carried out within the school setting with a focus on students, parents and teachers. Objectives: the main aim was to identify useful actions and precautions to help face cyberbullying (on smartphone and mobile applications) using technology to create a campaign of peer to peer sensi…