Leaders\u2019 competence and warmth: Their relationships with employees\u2019 well-being and organizational effectiveness

The aim of this work was to investigate competence and warmth \u2014 the two basic dimensions of social judgment \u2014 as dimensions employees use to evaluate their supervisors. A mediation model was tested in which supervisor\u2019s perceived competence and warmth were associated with relevant outcomes (lower burnout, weaker turnover intentions, more frequent citizenship behaviors) through the mediation of affective organizational commitment (AOC). In Study 1, data were collected from employees of a company in the water service sector. In Study 2, participants were financial promoters. In Study 3, the sample included employees from different organizations. As hypothesized, the perception of one\u2019s supervisor as competent (Studies 1-3) and warm (Study 3) was related to employees\u2019 lower burnout, weaker turnover intentions, more frequent prosocial behaviors through the mediation of AOC. Theoretical and practical implications of findings are discussed

Evaluation of a benchmark on dynamic reliability via Fluid Stochastic Petri Nets

The paper presents the evaluation of a benchmark on dynamic reliability. Such system consists of a tank containing some liquid, two pumps and one valve to renew the liquid in the tank, a heat source warming the liquid, and a controller acting on the state of the components. Three failure conditions are possible: the dry out, the over\ufb02ow or the high temperature of the liquid. Due to the presence of continuous variables, such as the liquid level and temperature, the system is modelled as a Fluid Stochastic Petri Net which is the object of simulation obtaining the unreliability evaluation of the system

Modelling dynamic reliability via Fluid Petri Nets

Combinatorial models for reliability analysis (like fault-trees or block diagram) are static models that cannot include any type of component dependence. In the CTMC (Continuous Time Markov Chain) framework, the transition rates can depend on the state of the system thus allowing the analyst to include some dependencies among components. However, in more general terms, the system reliability may depend on parameters or quantities that vary continuously in time (like temperature, pressure, distance, etc.). Systems whose behavior in time can be described by discrete as well as continuous variables, are called hybrid systems. In the dependability literature, the case in which the reliability characteristics vary continuously versus a process parameter, is sometimes referred to as dynamic reliability [1]. The modelling and analysis of hybrid dynamic systems is an open research area. The present paper discusses the evaluation of a benchmark on dynamic reliability proposed in [1] via a modelling framework called Fluid Stochastic Petri Net (FSPN)

New tools for scientific learning in the EduSeis project: the e-learning experiment

The Educational Seismological Project (EduSeis) is a scientific and educational project, the main aim of which is the development and implementation of new teaching methodologies in Earth Sciences, using seismology as a vehicle for scientific learning and awareness of earthquake risk. Within this framework, we have recently been experimenting with new learning and information approaches that are mainly aimed at a high school audience. In particular, we have designed, implemented and tested a model of an e-learning environment in a high school located in the surroundings of the Mt. Vesuvius volcano. The proposed e-learning model is built on the EduSeis concepts and educational materials (web-oriented), and is based on computer-supported collaborative learning. Ten teachers from different disciplines and fifty students at the ITIS «Majorana» technical high school (Naples) have been taking part in a cooperative e-learning experiment in which the students have been working in small groups (communities). The learning process is assisted and supervised by the teachers. The evaluation of the results from this cooperative e-learning experiment has provided useful insights into the content and didactic value of the EduSeis modules and activities. The use of network utilities and the «Learning Community» approach promoted the exchange of ideas and expertises between students and teachers and allowed a new approach to the seismology teaching through a multidisciplinary study

Analysis of an Electric Vehicle Charging System Along a Highway

To reduce carbon emission, the transportation sector evolves toward replacing internal combustion vehicles by electric vehicles (EV). However, the limited driving ranges of EVs, their long recharge duration and the need of appropriate charging infrastructures require smart strategies to optimize the charging stops during a long trip. These challenges have generated a new area of studies that were mainly directed to extend the classical Vehicle Routing Problem (VRP) to a fleet of commercial EVs. In this paper, we propose a different point of view, by considering the interaction of private EVs with the related infrastructure, focusing on a highway trip. We consider a highway where charging stations are scattered along the road, and are equipped withmultiple chargers. Using Fluid Stochastic Petri Nets (FSPN), the paper compares different decision policies when to stop and recharge the battery to maximize the probability of a car to reach its destination and minimize the trip completion time

Reliability analysis of dynamic systems by translating temporal fault trees into Bayesian networks

Classical combinatorial fault trees can be used to assess combinations of failures but are unable to capture sequences of faults, which are important in complex dynamic systems. A number of proposed techniques extend fault tree analysis for dynamic systems. One of such technique, Pandora, introduces temporal gates to capture the sequencing of events and allows qualitative analysis of temporal fault trees. Pandora can be easily integrated in model-based design and analysis techniques. It is, therefore, useful to explore the possible avenues for quantitative analysis of Pandora temporal fault trees, and we identify Bayesian Networks as a possible framework for such analysis. We describe how Pandora fault trees can be translated to Bayesian Networks for dynamic dependability analysis and demonstrate the process on a simplified fuel system model. The conversion facilitates predictive reliability analysis of Pandora fault trees, but also opens the way for post-hoc diagnostic analysis of failures

Moment Matching-Based Distribution Fitting with Generalized Hyper-Erlang Distributions

This paper describes a novel moment matching based fitting method for phase-type (PH) distributions. A special sub-class of phase-type distributions is introduced for the fitting, called generalized hyper-Erlang distributions. The user has to provide only two parameters: the number of moments to match, and the upper bound for the sum of the multiplicities of the eigenvalues of the distribution, which is related to the maximal size of the resulting PH distribution. Given these two parameters, our method obtains all PH distributions that match the target moments and have a Markovian representation up to the given size. From this set of PH distributions the best one can be selected according to any distance function

The Cross-Cultural Invariance of the Servant Leadership Survey: A Comparative Study across Eight Countries

This paper tests and confirms the cross-cultural equivalence of the Servant Leadership Survey (SLS) in eight countries and languages: The Netherlands, Portugal, Germany, Iceland, Italy, Spain, Turkey and Finland. A composite sample consisting of 5201 respondents from eight countries that all filled out the SLS was used. A three-step approach was adopted to test configural invariance, measurement equivalence, and structural equivalence. For the full 30-item version of the SLS, configural invariance and partial measurement equivalence were confirmed. Implications of these results for the use of the SLS within cross-cultural studies are discussed