Search results for "Reference"
showing 10 items of 2491 documents
Taste heterogeneity and latent preferences in the choice behaviour of freight transport operators
2013
In this paper we show that individual attitudes of road carriers and their latent preferences toward specific freight service attributes do play a role in determining their mode choices. Specifically, we contribute to the empirical literature on freight agents' mode choice by exploring the role of the "perceived importance" of the most relevant service dimensions in determining the attractiveness of two alternatives to "all-road" transport: logistics terminals and road-sea intermodal services. This is carried out through a revealed/stated preference experiment and a mixture of logit framework. Our results support the hypothesis that operators' attitudes towards time, punctuality and risk of…
Estimating the cost of improving service quality in water supply: A shadow price approach for England and wales
2015
Service quality to customers is an aspect that cannot be ignored in the performance assessment of water companies. Nowadays water regulators introduce awards or penalties to incentivize companies to improve service quality to customers when setting prices. In this study, the directional distance function is employed to estimate the shadow prices of variables indicating the lack of service quality to customers in the water industry i.e., written complaints, unplanned interruptions and properties below the reference level. To calculate the shadow price of each undesirable output for each water company, it is needed to ascribe a reference price for the desirable output which is the volume of w…
Relativistic Positioning Systems in Flat Space-Time: The Location Problem
2013
The location problem in relativistic positioning is considered in flat space-time. When two formal solutions are possible for a user (receiver) of the system, its true location may be obtained from a standard set of emission data extended with an observational rule. The covariant expression giving the location of the user in inertial coordinates is decomposed with respect to an inertial observer.
Further Developments and Tests of a Progressive Algorithm for Multiple Criteria Decision Making
1993
P. Korhonen, H. Moskowitz, and J. Wallenius (1986) developed a progressive algorithm and the supporting theory for modeling and solving multiple criteria decision problems with discrete alternatives. A special feature of the algorithm is that it relaxes the usual assumption of a fixed set of available decision alternatives and complete knowledge of a decision maker's (DM's) preference structure or value function. The algorithm is based on progressively sampling the decision space, obtaining preference information from the DM, determining the likelihood of finding possibly/surely better alternatives, and based on this information, continuing the search or terminating it by making the final …
Evaluating the performance of reference evapotranspiration equations with scintillometer measurements under Mediterranean climate and effects on oliv…
2014
The concept of reference potranspiration is widely used to support water resource management in agriculture and for irrigation scheduling, especially under arid and semi-arid conditions. The Penman-Monteith standardized formulations, as suggested by ASCE and FAO-56 papers, are generally applied for accurate estimations of ETo, at hourly and daily scale. When detailed meteorological information are not available, several alternative and simplified equations, using a limited number of variables, have been proposed (Blaney-Criddle, HargreavesSamani, Turc, Makkinen and Pristley-Taylor). In this paper, scintillometer measurements collected for six month in 2005, on an experimental plot under “re…
Western European Populations of the Ichneumonid Wasp Hyposoter didymator Belong to a Single Taxon
2019
Hyposoter didymator (Hymenoptera, Ichneumonidae) is a generalist solitary endoparasitoid of noctuid larvae. In the present work, we tested whether populations of H. didymator were divided in several genetically distinct taxa as described for many other generalist parasitoid species, and whether differences in H. didymator parasitism rates were explained by the insect host species and/or by the plant on which these hosts were feeding on. The genetic analysis of natural populations collected in different regions in France and Spain on seven different insect hosts and seven different host plants (775 individuals) showed that H. didymator populations belong to a unique single taxon. However, H.…
Simultaneous determinations of zirconium, hafnium, yttrium and lanthanides in seawater according to a co-precipitation technique onto iron-hydroxide
2013
Very low concentrations (pg mL 1 or sub-pg mL 1 level) along with the high salinity are the main problems in determining trace metal contents in seawater. This problem is mainly considered for investigations of naturally occurring YLOID (Y and Lanthanides) and Zr and Hf in order to provide precise and accurate results. The inductively coupled plasma mass spectrometry (ICP-MS), both in high and low resolution, offers many advantages including simultaneous analyses of all elements and their quantitative determination with detection limits of the order of pg mL 1. However in the analysis of YLOID in seawater, a better determination needs an efficient combination of ICP-MS measurement with a pr…
USING WRB TO MAP THE SOIL SYSTEMS OF ITALY
2012
Aim of this work was to test the 2010 version of the WRB soil classification for compilating a map of the soil systems of Italy at 1:500,000 scale. The source of data was the national geodatabase storing information on 1,414 Soil Typological Units (STUs). Though, basically, we followed WRB criteria to prioritize soil qualifiers, however, it was necessary to work out an original methodology in the map legend representation to reproduce the high variability inside each delineation meanwhile avoiding any loss of information. Each map unit may represent a combination of three codominant STUs at the most. Dominant STUs were assessed summing up the occurrence of STUs in the Land Components (LCs) …
Functional food characteristics in organic food products—the perspectives of Italian consumers on organic eggs enriched with omega-3 polyunsaturated …
2022
Abstract Innovation in organic food products plays an important role in further developing its competitiveness in the market and meeting the emerging consumers’ needs. However, few studies have analysed consumers’ points of view of innovations on organic food, limited to the change in the natural food composition or the enrichment of the nutritional contents of the product. This study, using experimental auctions, aims to overcome this gap by enriching the knowledge on organic consumers’ preference for organic food with functional characteristics. Specifically, this study analyses the willingness to pay (WTP) of 110 Italian consumers for organic eggs enriched with omega-3 polyunsaturated fa…