1,859 research outputs found
Quality versus productivity in service production systems: an organisational analysis
No full textThe study presents an organisational analysis into the linked issues of service productivity and perceived service quality. The operations management literature postulates that a trade-off exists between service productivity and perceived service quality, an assertion which is supported by evidence from managerial experiences and other academic researches. However, is it possible to prevail over the trade-off between productivity and perceived quality? Further, what is the effect of the trade-off on company profitability? To respond to these questions, a retrospective longitudinal study is performed, based on analysis of data collected from 52 offices of a major European banking group over the years 2010–2011. A first analysis verifies the existence of the trade-off. A second then examines the suitability of the employee incentive system intended to overcome the trade-off. Finally, a multiple linear regression model is developed in order to verify whether service productivity and perceived service quality impact on company profitability, and to what extent
Poesia in posa
No full textCatalogo della mostra, a cura di C. Gian Ferrari, M. Scolaro, C. Spadoni. Rilettura dell'opera di Felice Casorati con particolare attenzione al contesto di riferimento culturale e alle fonti, all'ambiente torinese che rappresentò il primo destinatario della sua opera. Analisi approfondite dei rapporti con gli intellettuali piemontesi, con Piero Gobetti, primo esegeta dell'arte di Casorati, e con i coniugi Gualino, importanti figure di committenti/mecenati
Partitioning a matrix to minimize the maximum cost
No full textAbstractA matrix A = [aij] of nonnegative integers must be partitioned into p blocks (submatrices) corresponding to a set of vertical cuts parallel to the columns and a set of horizontal cuts parallel to the rows. With each block is associated a cost equal to the sum of its elements. We consider the problem of finding a matrix partitioning that minimizes the cost of the block of maximum cost.In this paper a mathematical formulation of the problem is given and used to derive both exact and heuristic algorithms.Lower bounds and dominance criteria are exploited in a tree search algorithm for finding the optimal solution of the problem. Computational results of the proposed algorithm are given on a number of randomly generated test problems
Effect of the RF sputtering power on microstructural, optical and electrical properties of Al doped ZnO thin films
No full textZnO:Al (AZO) thin films have been deposited by radio frequency (RF) magnetron sputtering and RF power applied to the target has been varied in the range 600-1200 W. RF power effect on structural, electrical and optical properties was investigated and the relationship existing between these properties and the film lattice defect distribution was discussed. At the increasing of the RF power it was found that AZO films, having a preferential growth orientation along (002) direction, showed a decrease of the lattice distance indicating a less defected structure. Furthermore, at the increase of the RF power a higher optical absorption by free carriers, coupled with an increase of the band gap value, was observed. Resistivity varied from 1.1 × 10- 3 cm at 600 W down to a minimum value of 5.6 × 10- 4 cm at 1200 W, whereas the carrier density increased up to 1 × 1021 cm- 3. Lattice defect variation of AZO films was analyzed by photoluminescence (PL) measurements. Presence and amount of different lattice defects were evaluated for AZO films deposited at different RF powers. At 600 W the film structure was dominated by zinc vacancies (VZn), whereas for higher RF power the PL band associated with VZn decreased and interstitial oxygen (Oi) band remarkably increased. PL analysis revealed that extrinsic Al doping is the dominant effect on the conductivity enhancement. It was hypothesized that at higher RF power a more effective diffusion phenomenon can give more effective Al doping and less amount of zinc vacancies. As a consequence, Al atoms are more effectively trapped into the structure. © 2015 Elsevier B.V
"Un poco al di sopra dei nostri sensi": scrittori e artisti verso Oriente
No full textIl saggio indaga la tradizione dll'orientalismo negli scrittori francesi e italiani che a cominciare dalla fine dell'800 hanno descritto viaggii n paese extraeuropei
The Environmental And Human Health Risk Assessment: Methodology And Decision Support Systems
No full textThe presence of sources of pollution which release chemicals of concern into environmental media
designate a major threat for human health and ecosystems. In general regulations prescribe the
observance of emission threshold values for single sources and quality limit values and alert
thresholds for separate environmental media, nevertheless the complete impact evaluation of
industrial, agricultural and civil activities on environment requires a detailed and global analysis, in
which manifold aspects of a specific area of interest are taken into account.
A complete Environmental and Human Health Risk Assessment (EHHRA) procedure to quantify
the adverse effects of exposure to carcinogenic or toxic substances is a fundamental focus both in
order to control and monitor the environmental impact of existing plants and infrastructures and to
prevent adverse effects (especially on human beings) by means of good manages of new
installations and land use planning.
The analysis is a well-consolidated procedure, and requires the integration of information on
environmental and chemicals database, inter and intra media dispersion models output, site
description maps, exposure patterns and demographic database. In addition, to include uncertainties
and variability, probabilistic risk assessment and sensitivity analysis of calculation input parameters
form an integral part of the analysis.
As a result, the designing and conducting analysis of the effects of contaminants on human health is
a complex and time expensive procedure, which call for the support of Decision Support Systems
(DSS). A useful assistance in managing a large amount of spatial and non-spatial data is represented
in particular by the GIS Decision Support Systems, explicitly designed to assist decision research
process for complex spatial problems such as EHHRA.
An examination of the existing literature on human health risk assessment tools is presented.
Among these, the description of the EHHRA-GIS tool is detailed, pointing out the open architecture
of the methodology approach, the implemented models, the performance and the potential
developments of the tool. The upper-bound excess lifetime cancer risk and non-carcinogenic
hazards are evaluated as risk measures, the spatial distribution of which is calculated and mapped
on the involved territory
Advanced light-scattering materials: Double-textured ZnO:B films grown by LP-MOCVD
No full textDouble-textured ZnO:B layers with enhanced optical scattering in both short and long wavelength regions have been successfully fabricated using MOCVD technique through a three step process. Growth of double-textured structures has been induced by wet etching on polycrystalline ZnO surface.Our double-layer structure consists of a first ZnO:B layer wet etched and subsequently used as substrate for a second ZnO:B layer deposition. Polycrystalline ZnO:B layers were etched by utilizing diluted solutions of fluoridic acid (HF), chloridric acid (HCl) and phosphoric acid (H3PO4) and their effect on surface morphology modification was systematically investigated. The morphology of the second deposited ZnO layer strongly depended on the surface properties of the etched ZnO first layer. Growth of cauliflower-like texture was induced by protrusions presence on the HCl etched surface. Optimized double-layer structure shows a cauliflower-like double texture with higher RMS roughness and increased spectral haze values in both short and long wavelength regions, compared to conventional pyramidal-like single texture. Furthermore, this highly scattering structure preserves excellent optical and electrical properties. © 2013 Elsevier B.V. All rights reserved
Assessing the safety performance of fireproofing materials for equipment protection
No full textFire scenarios in off-shore installations have high potential to cause severe asset damage and initiate cascading events. Fireproofing materials are a consolidated technique for passive fire protection of equipment units and of supporting structures. However current practice in rating fireproofing materials does not provide sufficient information for safety management purposes (e.g. can not be used to predict ‘time-to-failure’ of pressurized units, which is fundamental in planning adequate egress and emergency procedures). The current contribution presents the results of a study aimed at a better understanding of the performance of fireproofing materials in the protection of critical equipment. The study included results from both experimental and simulation techniques. Different fireproofing materials (inorganic fiber, lightweight concrete, intumescent resin) were considered. The experimental activity was aimed at the definition of fundamental models to describe the thermo-physical properties of the materials. Specific simulation models were used to describe heat transfer through the material. The results were validated by lab-scale tests. Finite Element Model (FEM) simulation allowed for the description of the expected behaviour of process equipment exposed to different fire conditions. The FEM simulation was validated, again, with available results from large scale tests on storage vessels. The study led to a better understanding of the dynamics underlying the effective design for passive fire protection. The criticalities and limits of use of the alternative fireproofing options were identified. As such, the proposed approach paves the way for a safer and more cost effective design of passive fire protection systems in off-shore facilities
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