169,831 research outputs found
Investigating determinants of choice and predicting market shares of renewable-based heating systems under alternative policy scenarios
No full textFostering the uptake of heating technologies based on renewable resources is an important part of the EU energy policy. Yet, despite e!orts to promote their dif-fusion, heating systems based on fossil fuels are still predominant. In order to better tailor energy policies to citizens preferences, it is crucial to collect accurate informa-tion on their determinants of heating choices. At this purpose, we adopted a choice experiment and a latent class model to analyze preferences of householders in the Veneto region (North-East Italy) for di!erent heating systems and their key features. We focused on three devices based on biomass and three on fossil fuels, and account-ed for technical, economic and environmental characteristics of such systems. Model estimates highlight the presence of substantial preference heterogeneity among the population, which can be partially explained by citizens socio-demographics. We also use model outputs to simulate market shares for heating systems under alternative policy scenarios. Results provide interesting suggestions to inform the design of poli-cies aimed at fostering the adoption of biomass-based heating systems
: A Monte Carlo Evaluation
No full textThe logit-mixed logit (LML) model advances choice modeling by generalizing previous parametric and semi-nonparametric specifications and allowing retrieval of flexible taste distributions. Using standard operating conditions in the field, we report results from Monte Carlo experiments designed to assess the finite sample bias-variance tradeoff for the LML using as a benchmark conventional Mixed logit models (MXL) under asymmetric and multimodal taste distributions. The LML specification always outperforms the MXL in terms of bias, but when the variance around modes is high the mean squared error (MSE) is lower than that of MXL only at sample sizes larger than usual and with some nuances. D-error minimizing experimental design predicated on multinomial logit significantly reduces MSE, but no clear winner is found between polynomial, step, and spline functions for the multidimensional grid function. Analysis of empirical data from a choice experiment on tap water shows that multimodality emerges only if higher number of node parameters are used in the LML
Antecedent Volition and Spatial Effects: Can Multiple Goal Pursuit Mitigate Distance Decay?
No full textThe estimation of choice models that explicitly incorporate economic agents’ goal-related information has yet to receive focused attention from practitioners. Despite recent advances on spatial analysis in stated preference studies, there is still no evidence on how spatial effects interact with goal pursuit. In this study we propose a modelling framework to analyse how goal pursuit influences choices and query whether pursuit of important goals makes individuals less distance-sensitive. We estimate a hybrid choice model with latent variables to investigate the role of goals and distance on preferences for recreational site attributes. We use data from a choice experiment involving selection among different sites in Dolomiti Bellunesi National Park (Italy). Our results show that goal pursuit has a significant effect on site choice probability and that distance disutility is decreased when individuals visit recreational sites due to pursuit of important goals. This result indicates that willingness to pay inferences concerning spatially distributed activities depend crucially on the spatial distribution of motivations for participation
Aspetti regolatori nella procedura di A.I.C.
No full textI medicinali oppiacei, ansiolitici, antidepressivi e antiepilettici, presentano particolari criticità per quanto riguarda i loro effetti sulla guida e sull’uso di macchinari.
Sotto il profilo regolatorio, la normativa che disciplina l’Autorizzazione all’Immissione in Commercio dei medicinali (Regolamento CE 726/2004 e s.m.i.; Decreto Legislativo 219/06 e s.m.i.) colloca la menzione di possibili effetti sulla capacità di guidare un veicolo o di azionare macchinari nell’ambito più generale delle disposizioni per la redazione del foglietto illustrativo.
Pertanto, nelle fasi della procedura di A.I.C. è necessario riferirsi ai disposti degli articoli 14 (compreso l’Allegato 2 previsto dal comma 1), 73, 74 del Decreto Legislativo 219/06.
L’art. 14, nel stabilire le informazioni obbligatorie del “Riassunto delle caratteristiche del prodotto”, dispone che al punto 4.7 si includano gli Effetti sulla capacità di guidare veicoli e sull'uso di macchinari. Tale disposto, trova riscontro nella norma di etichettatura del medicinale prevedendo che debba riportare l’indicazione delle avvertenze speciali eventualmente necessarie, con particolare riferimento alle controindicazioni provocate dalla interazione del medicinale con bevande alcoliche e superalcoliche, nonché l'eventuale pericolosità per la guida derivante dall'assunzione (Art. 73 comma 1, lettera g). Inoltre, il foglio illustrativo prevede una lista delle informazioni “da conoscere prima di assumere il medicinale”, tra le quali interazioni con altri medicinali e altre forme di interazione (ad esempio con alcool, tabacco, alimenti), che possono influire sull'azione del medicinale nonché sulla capacità di guidare un veicolo o di azionare macchinari.
Le norme tecniche sin qui esposte, derivano da linee guida quali la “A GUIDELINE ON SUMMARY OF PRODUCT CHARACTERISTICS (SmPC)” September 2009, Rev 2, inclusa in The Rules Governing Medicinal Products in the European Union Volume 2C Notice to Applicants.
Nelle linee guida, relativamente agli aspetti clinici, vengono descritte le avvertenze speciali e precauzioni di impiego del medicinale secondo un ordine che dovrebbe, in linea di principio, essere determinato dall'importanza delle informazioni di sicurezza fornite.
Il contenuto del messaggio dovrà essere necessariamente diverso per ogni prodotto e in funzione delle condizioni terapeutiche che è destinato a trattare, fermo restando che informazioni su di un rischio specifico devono essere riportate solo quando il rischio porta ad una precauzione.
Specificatamente agli effetti sulla capacità di guidare ed usare macchinari, le linee guida, impongono di specificare se il medicinale presenta:
a) nessuna o influenza trascurabile;
b) influenza minore;
c) influenza moderata;
d) grande influenza.
La classificazione, articolata nei quattro punti (a, b, c, d), deve essere basata sui profili farmacocinetici e farmacodinamici, sulle reazioni avverse note e/o su specifici studi su una rilevante popolazione target affrontando le prestazioni correlate alla guida di autoveicoli o macchinari
Is local and organic produce less satiating? Some evidence from a field experiment
No full textWe investigate consumers' preferences towards local and organic food via a framed field experiment involving revealed multiple discrete-continuous choices. Participants were endowed with a cash amount as a budget to purchase any desired quantity of different products. We modelled choices via the multiple discrete-continuous nested extreme value model. Central to our investigation is the test of the hypothesis of the constant effect of attitudes across consumption doses, which is normally an assumption invoked a priori and without testing in discrete choice analyses. Our results support the hypothesis and reveal a strong preference towards organic and local products, associated with both the highest baseline utility and the lowest satiation effect
High shear granulation of crystalline sugars
No full textSugars can be used in granulation processes with different purposes: as diluents, binders, taste masking agents, sweeteners and agents for drug controlled release (e.g. sugar beads). They are soluble and sticky excipients and their processing in high shear granulators may be difficult: they can easily adhere to mixer walls or lead to uncontrolled granule growth. The purpose of this research was to evaluate the different behaviour in high shear wet granulation of four selected sugars: mannitol, sorbitol, xylitol and sucrose (size range of 60-300 μm). They were characterized by flowability and viscosity measurements and their solid state was studied by X-ray diffraction. Also the hygroscopicity was evaluated by conditioning powders at different relative humidity (RH 65 and 80%). Results highlighted that the humidity uptake did not produce changes in the solid state of the sugars but caused a reduction in flowability that was stronger in the case of sorbitol and xylitol. Powder flowability showed correlation to hygroscopicity but not to the final thickening of dissolved sugars. Granulation experiments demonstrated the feasibility of the process with the selected sugars and the possibility to predict the amount of water necessary to the process through mixer torque rheometer measurements
Formulazione e caratterizzazione in vitro di un sistema utoemulsionante solido contenente monacolina K
No full textStochastic Well-Formed Coloured Nets for Symmetric Modelling Applications
No full textThe class of stochastic well-formed colored nets (SWN's) was defined as a syntactic restriction of stochastic high-level nets. The interest of the introduction of restrictions in the model definition is the possibility of exploiting the symbolic reachability graph (SRG) to reduce the complexity of Markovian performance evaluation with respect to classical Petri net techniques. It turns out that SWN's allow the representation of any color function in a structured form, so that any unconstrained high-level net can be transformed into a well-formed net. Moreover, most constructs useful for the modeling of distributed computer systems and architectures directly match the “well-formed” restriction, without any need of transformation. A nontrivial example of the usefulness of the technique in the performance modeling and evaluation of multiprocessor architectures is include
Determinants of Recreational Activities Choice in Protected Areas
No full textConciliating nature conservation and tourism development is an increasingly important task for authorities in charge of managing protected areas and requires an adequate knowledge of visitors′ preferences and recreational behavior. In this light, we used data collected by means of a choice experiment to investigate recreational preferences at Dolomiti Bellunesi National Park, a protected area located in Northeastern Italy. More specifically, we analyzed the determinants of visitors’ decisions to engage with different activities in the park. This is important information for park managers, as different recreational activities have both different impact on the natural heritage and different capability to generate revenue for nature conservation and for enhancing the quality of life of local communities. The findings of our study suggest that the choice of recreational activities is mainly driven by the features of recreational sites and by visitors’ personal characteristics. Concerning park features, visitors’ choices seem to be mostly driven by features directly related to each activity, such as thematic trails for hiking and climbing routes for rock climbing. Among visitors′ characteristics, we found that both previous experience with the activity and socio-demographic characteristics had a significant effect on activity choice. Overall, the results of our study can help park authorities in developing management plans aimed specifically at attracting a larger number of visitors of a certain type, which is an important tool to foster the more sustainable forms of tourism
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