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Car Parameters Identification by Handling Manoeuvres   总被引:1,自引:0,他引:1  
A methodology is presented for identifying car parameters by studying the vehicle's handling. The methodology is based on the Kalman filter and makes it possible to determine the parameters on the basis of the results obtained from standard, on-road handling manoeuvres.  相似文献   
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Environmental sustainability in the port industry is of growing concern for port authorities, policy makers, port users and local communities. Innovation can provide a solution to the main environmental issues, but often meets resistance. While certain types of technological or organisational innovation can be satisfactorily analysed using closed system theories, in the case of seaports and in particular in the area of environmental sustainability, more advanced conceptual frameworks have to be considered. These frameworks need to be able to account for the multiple stakeholder nature of the port industry and of the network and vertical interactions that environmental sustainability calls for. This article investigates successful innovations improving environmental sustainability of seaports. The proposed framework builds in part on research concepts developed in the InnoSuTra EU FP7 project. From a methodological perspective, this article develops a method for quantifying the degree of success of innovation with respect to a set of specific objectives. Several case studies are used to test the framework against real innovation examples, such as onshore power supply, or alternative fuels. In this article, we argue that only those innovations that fit dynamically port actors’ demands and the port institutional environment stand a chance to succeed.  相似文献   
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In the framework of the Italian Research Programme in Antarctica (PNRA) an oceanographic cruise was carried out between December 2000 and February 2001 in the Western Ross Sea. n-Alkanes and PAHs concentrations were analysed in sea-water samples collected at different depths at four sites (D, B, CA2, and CA). Vertical profiles of pressure, temperature, salinity and fluorescence were also performed in order to distinguish the water masses present in the sampling areas. n-Alkanes concentrations were consistent with those found in the same area during previous expeditions and showed higher values in the particulate due to the low temperatures. n-Alkanes profiles exhibited different features in the dissolved and particulate phases. The dissolved phase was characterised by a bimodal distribution with two maxima at C16 and C24 and prevalent compounds in the range C15–C32 whereas particulate was strongly dominated by long chain n-alkanes C23–C34 with C24 (Site B, CA and CA2) or C32 (Site B) as Cmax. CPI values and Pr/Ph ratios suggested a prevalent biogenic origin for aliphatic hydrocarbons. n-Alkanes vertical distributions were affected by the dynamic of the pack-ice melting and phytoplankton activity as well by the chemical–physical properties of water masses. Higher n-alkanes values were found in the High Salinity Shelf Waters (HSSW), lower n-alkanes values were found in the Antarctic Surface Waters (AASW) and Modified Circumpolar Deep Water (MCDW).The low PAHs concentration levels confirmed the still pristine character of the Antarctic environment. Neither particular trend in total PAHs concentrations along the water column and nor correlations with the most characteristic water masses of the investigated area of the Ross Sea were observed, except that total PAH higher concentrations were generally observed in correspondence of HSSW.  相似文献   
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The paper reports a modelling system to simulate goods movements at an urban scale. It allows joint analysis of choices made by end-consumers (assumed to be families) and retailers. These movements are examined at two levels: analysis of commodity flows, in terms of quantity, generated by the consumption of commodities; analysis of commodity flows, in terms of vehicles, due to restocking. The first level allows us to calculate the goods quantity flows due to consumption and restocking; the second level allows us to determine the service, vehicles used and target time, as well as the route chosen for restocking sales outlets in order to estimate vehicle flows on the urban/metropolitan transportation network. The modelling system is a multi-step model and considers a disaggregated approach for each decisional level.  相似文献   
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Cascetta  Ennio  Russo  Francesco 《Transportation》1997,24(3):271-293
Traffic counts on network links constitute an information source on travel demand which is easy to collect, cheap and repeatable. Many models proposed in recent years deal with the use of traffic counts to estimate Origin/Destination (O/D) trip matrices under different assumptions on the type of "a-priori" information available on the demand (surveys, outdated estimates, models, etc.) and the type of network and assignment mapping (see Cascetta & Nguyen 1988). Less attention has been paid to the possibility of using traffic counts to estimate the parameters of demand models. In this case most of the proposed methods are relative to particular demand model structures (e.g. gravity-type) and the statistical analysis of estimator performance is not thoroughly carried out. In this paper a general statistical framework defining Maximum Likelihood, Non Linear Generalized Least Squares (NGLS) and Bayes estimators of aggregated demand model parameters combining counts-based information with other sources (sample or a priori estimates) is proposed first, thus extending and generalizing previous work by the authors (Cascetta & Russo 1992). Subsequently a solution algorithm of the projected-gradient type is proposed for the NGLS estimator given its convenient theoretical and computational properties. The algorithm is based on a combination of analytical/numerical derivates in order to make the estimator applicable to general demand models. Statistical performances of the proposed estimators are evaluated on a small test network through a Monte Carlo method by repeatedly sampling "starting estimates" of the (known) parameters of a generation/distribution/modal split/assignment system of models. Tests were carried out assuming different levels of "quality" of starting estimates and numbers of available counts. Finally NGLS estimator was applied to the calibration of the described model system on the network of a real medium-size Italian town using real counts with very satisfactory results in terms of both parameter values and counted flows reproduction.  相似文献   
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The Goro lagoon has been adversely affected by intense anthropogenic impacts, which have resulted in deterioration of the lagoon's environmental health. An intervention at the lagoon's secondary mouth was done in order to improve the water exchange between the lagoon and the sea and to reclaim the lagoon's floor. This intervention comprised reprofiling the submerged sandspit platform and the tidal channel and nourishing the barrier island. After completion of the intervention, clam production increased by 28% and the lagoon's ecological quality substantially improved. The project utilized some of the eight principles of integrated coastal zone management to reach the best compromise between the socioeconomic needs and preservation of the lagoon. The realization of the successful intervention was first secured in a memorandum of agreement that was drafted by negotiations between the Emilia-Romagna Region Council, the Province of Ferrara, Goro Municipality, and the local fishermen's association. Two committees managed the intervention and ensured that all stakeholders participated in the decisionmaking process. The collaboration between public and private sectors enabled the forging of a cost-effective intersectoral intervention with a long-term perspective, which fulfilled the specific ecological needs of the lagoon and guaranteed sustainable development for the lagoon's adjacent human communities.  相似文献   
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Using a dynamic approach, employing data on job mobility, we demonstrate that university workers?? marginal willingness to pay for reducing commuting distance is about ?0.25 per kilometre travelled. This corresponds to a marginal willingness to pay for reducing commuting time of about 75?% of the net average hourly wage. For females, the willingness to pay is substantially higher than for males. It is also substantially higher for workers that work few hours per day, as predicted by theory.  相似文献   
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The maritime and port sector is widely considered conservative concerning the ability to introduce innovation in respect to other industries. This may be due to the lack of cooperative interactions among the several players involved. It does not mean that innovation does not occur in this industry. Along with some technical innovations, managerial, organizational, and cultural innovations also take place in the sector. The literature has considered the assessment and effects of the adoption of particular innovation, but still few studies underline the innovation path in a broad sense with a specific focus on terminal operators. The present article aims at filling this gap through a field analysis grouping together case studies developed in different world regions and examining the adoption path of innovation through a mix of three different techniques (i.e. the H- and I-indexes, a Systems of Innovation Analysis, and a Qualitative Comparative Analysis). Research outcomes underline how, even if no unique recipe for success can be found, specific factors (e.g. a ranking of innovation objectives, coordination among actors, and institutions) can influence the achievement of success. The analyses allow suggesting strategic and policy advice that may help link in a better way the innovation drivers with their actual effects.  相似文献   
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