832 research outputs found
The 2002-2003 Stromboli eruption
Questo documentario mostra i momenti
principali della fase eruttiva 2002-2003 del
Vulcano Stromboli e il lavoro svolto dal
personale dell’INGV nell’ambito del Servizio
Nazionale di Protezione Civile.
Il documentario è stato realizzato da Lilli
Freda e Piergiorgio Scarlato con le immagini
riprese durante l’emergenza; la cronologia
dell’eruzione è stata ricostruita basandosi
sulla loro esperienza personale e sui
comunicati ufficiali INGV.
Il filmato è stato presentato alla comunità
scientifica durante “2004 General Assembly
of International Association of Volcanology
and Chemistry of the Earth’s Interior”
(Pucon, Cile).
This documentary illustrates the topic events
of the 2002-2003 eruptive phase of the
Stromboli Volcano and the work carried out
by the INGV personnel within the Civil
Protection National Service.
The documentary was made by Lilli Freda and
Piergiorgio Scarlato with imagines filmed
during the emergency; the chronology of the
eruption was reconstructed on the basis of
their personal experience and of the official
INGV communications. The movie was shown
to the scientific community during the “2004
General Assembly of International
Association of Volcanology and Chemistry of
the Earth’s Interior” (Pucon, Chile)
Immigrant Entrepreneurs in the USA: A Conceptual Discussion of the Demands of Immigration and Entrepreneurial Intentions
Purpose: Given the growing number of immigrant entrepreneurs in the USA, the purpose of this paper is to better understand the behaviors of this subgroup of entrepreneurs. Specifically, the paper aims to understand the unique challenges faced by immigrant entrepreneurs and how environmental challenges affect decisions to grow or abandon their ventures.
Design/methodology/approach: To make the theoretical arguments in this conceptual paper, the authors draw on the theory of planned behavior developed by Ajzen (1985), which suggests that a person’s behavior is predicted by their intention, and intentions are predicted by one’s attitudes, subjective norm and perceived behavioral control.
Findings: The paper provides theoretical insights on the effect of demands of immigration on the intentions of immigrant entrepreneurs to engage in three specific entrepreneurial behaviors: new venture formation, growth and abandonment. The authors propose that immigrant entrepreneurs deal with increased stress yet continue to maintain higher intentions to found new ventures compared to non-immigrants. Contrastingly, the authors also propose that the stress and obstacles immigrant entrepreneurs face reduce their intentions to grow their firms and increase their intentions to abandon their firms. The authors also explore entrepreneurial resilience as a possible moderating factor between stress and entrepreneurial intentions of immigrant entrepreneurs.
Research limitations/implications: First, the authors do not distinguish between immigrants from different nations or parts of the world or having different backgrounds. Second, the authors do not fully develop or incorporate the element of coping. Also, our paper is limited to behaviors of immigrant entrepreneurs with micro- and small-businesses.
Practical implications: Venture capitalists could benefit from empirical results of these propositions as funding decisions may need to include consideration of the proposed effects of stress and demands of immigration.
Originality/value: This paper meets an identified need to examine the effects of immigrant-specific issues such as the demands of immigration on the behaviors of this growing group of entrepreneurs
Skills Shortages and Job Satisfaction–Insights from the Gold-Mining Sector of South Africa
Published ArticleThe article reports on the levels of job satisfaction of mining-sector employees,
as well as the perceived influence of skills shortages on the job satisfaction of
these employees. The findings emanating from the study indicate that the
respondents did experience job satisfaction, and that perceived skills shortages
in two core occupational categories did not influence job satisfaction. The study has augmented the body of knowledge vis-à-vis the relationship between
perceived skills shortages and job satisfaction. This is particularly important,
since the mining industry remains a key driver of economic growth in South
Africa, despite the negative perceptions that have beset the sector following the
Marikana massacre of 2012
3D Multi-Robot Exploration with a Two-Level Coordination Strategy and Prioritization
This work presents a 3D multi-robot exploration framework for a team of UGVs
moving on uneven terrains. The framework was designed by casting the two-level
coordination strategy presented in [1] into the context of multi-robot
exploration. The resulting distributed exploration technique minimizes and
explicitly manages the occurrence of conflicts and interferences in the robot
team. Each robot selects where to scan next by using a receding horizon
next-best-view approach [2]. A sampling-based tree is directly expanded on
segmented traversable regions of the terrain 3D map to generate the candidate
next viewpoints. During the exploration, users can assign locations with higher
priorities on-demand to steer the robot exploration toward areas of interest.
The proposed framework can be also used to perform coverage tasks in the case a
map of the environment is a priori provided as input. An open-source
implementation is available online
Local-scale forcing effects on wind flows in an urban environment: Impact of geometrical simplifications
Wind flow in urban areas is strongly affected by the urban geometry. In the last decades most of the geometries used to reproduce urban areas, both in wind-tunnel (WT) tests and Computational Fluid Dynamics (CFD) simulations, were simplified compared to reality in order to limit experimental effort and computational costs. However, it is unclear to which extent these geometrical simplifications can affect the reliability of the numerical and experimental results. The goal of this paper is to quantify the deviations caused by geometrical simplifications. The case under study is the district of Livorno city (Italy), called \ue2\u80\u9cQuartiere La Venezia\ue2\u80\u9d. The 3D steady Reynolds-averaged Navier-Stokes (RANS) simulations are solved, first for a single block of the district, then for the whole district. The CFD simulations are validated with WT tests at scale 1:300. Comparisons are made of mean wind velocity profiles between WT tests and CFD simulations, and the agreement is quantified using four validation metrics (FB, NMSE, R and FAC1.3). The results show that the most detailed geometry provides improved performance, especially for wind direction \uce\ub1 = 240\uc2\ub0 (22% difference in terms of FAC1.3)
Meaning coconstruction in group counseling: The development of innovative moments
This study discusses a model of group counseling, the narrative mediation path (NMP), which is a
unique narrative, multimodal approach that combines four narrative modes (metaphoric, iconographic,
writing, and bodily
)
and the narrative group. The purpose of the NMP is to foster reflexive processes
with underachieving university students and to improve their academic performance. The study
analyzes a single case of group counseling for seven underachieving economics students at an Italian
university and the process of meaning construction among NMP narrative modes and the follow-up
session. It applies the innovative moments coding system, a reliable method for studying change by
tracking narrative innovations in sessions. More specifically, we focus on how innovative moments
(IMs: action, reflection, protest, and reconceptualization) evolve during the four different narrative
modes and the follow-up session. The findings suggest that the NMP fosters narrative innovations,
mainly of a reflexive nature (reflection and reconceptualization). Moreover, during counseling and
the follow-up session, the pattern of change is primarily characterized by reconceptualization IMs,
the most complex form of narrative innovationEuropean Commission (Grant Agreement 2011-4040 Project 517750-LLP-1-2011-1-IT-ERASMUS-ESIN
A general viscosity model of Campi Flegrei (Italy) melts
Viscosities of shoshonitic and latitic melts, relevant to the Campi Flegrei caldera
magmas, have been experimentally determined at atmospheric pressure and 0.5 GPa,
temperatures between 840 K and 1870 K, and H2O contents from 0.02 to 3.30 wt%.
The concentric cylinder technique was employed at atmospheric pressure to determine
viscosity of nominally anhydrous melts in the viscosity range of 101.5 - 103 Pa·s. The
micropenetration technique was used to determine the viscosity of hydrous and anhydrous
melts at atmospheric pressure in the high viscosity range (1010 Pa·s). Falling sphere
experiments were performed at 0.5 GPa in the low viscosity range (from 100.35 to 102.79 Pa·s)
in order to obtain viscosity data of anhydrous and hydrous melts. The combination of data
obtained from the three different techniques adopted permits a general description of viscosity
as a function of temperature and water content using the following modified VFT equation:
where η is the viscosity in Pa·s, T the temperature in K, w the H2O content in wt%, and a, b, c,
d, e, g are the VFT parameters. This model reproduces the experimental data (95
measurements) with a 1σ standard deviation of 0.19 and 0.22 log units for shoshonite and
latite, respectively. The proposed model has been applied also to a more evolved composition
(trachyte) from the same area in order to create a general model applicable to the whole
compositional range of Campi Flegrei products.
Moreover, speed data have been used to constrain the ascent velocity of latitic,
shoshonitic, and trachytic melts within dikes. Using petrological data and volcanological
information (geometrical parameters of the eruptive fissure and depth of magma storage), we
estimate a time scale for the ascent of melt from 9 km to 4 km depth (where deep and shallow
reservoirs, respectively, are located) in the order of few minutes. Such a rapid ascent should
be taken into account for the hazard assessment in the Campi Flegrei area
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