Maritime transportation, widely used both in international transport of goods and touristic purposes, has been identified as a significant source of ultrafine particles (UFP). In-land passenger ferry is a source of UF...Maritime transportation, widely used both in international transport of goods and touristic purposes, has been identified as a significant source of ultrafine particles (UFP). In-land passenger ferry is a source of UFP far less addressed;however, in locations with relatively high frequency of this transportation mode, it is expected that they contribute to an increase of their concentration. Moreover, the negative effects of UFP on human health and environment are known and therefore, monitoring UFP produced by ferries is vital to assess the degree of exposure of who work or live close to ferries’ terminals or downwind to their cruising path. This work aims to study the influence of in-land ferries activities on UFP in the urban/suburban areas near ferries’ terminals and downwind across the cruising path. The UFP monitoring campaign was carried out from September to December 2018 for 19 non-consecutive periods. The sampling sites were chosen in order to maximize measurements under downwind conditions and allow the association between ferry operation and UFP concentration response. Based on data collected, correlation analysis was performed between ferry’s traffic and particle number counting (PNC) of UFP, and also with meteorological variables. Results show an increase in PNC ranging from 25 to 197% during the third minute around a ferry movement and are moderate to positive significant correlations between PNC values and the number of ferry operations (r = 0.79 to r = 0.94), showing that UFP emitted by in-land ferries contributes to PNC increase. Moreover, negative correlations (r = -0.85 to r = -0.93) between PNC and wind intensity were also found.展开更多
The purpose of this paper is to introduce an innovative methodology in shipping investment evaluation based on simulation of a project cash flow. It concerns a complementary approach to current practices and its aim i...The purpose of this paper is to introduce an innovative methodology in shipping investment evaluation based on simulation of a project cash flow. It concerns a complementary approach to current practices and its aim is to provide more information mainly to ship-owners that consider the feasibility of deploying Ro-Ro Passenger ferries. The paper examines a typical semi-conventional RoPax ferry operating in the Aegean Sea. It addresses important economic, operational and procedural issues concerning risk evaluation. The current status is that risk is a notion still strange to main stakeholders. The Greek practice in performing a feasibility study for a project draws on investor＇s experience and feeling aided by a preliminary economic study. The main thesis of this paper is that there are alternative techniques to evaluate investment risk and measure profitability of a project. A Monte Carlo simulation in collaboration with a typical Ro-Ro cash-flow model is implemented to reveal the extent of risk and provide a useful tool for the assessment of future investments in Greek Short Sea Shipping.展开更多
Passenger car equivalent (PCE) is an important factor which is used to convert traffic volumes containing proportions of heavy good vehicles (HGVs) to a unify measure containing only passenger cars units (PCU). This p...Passenger car equivalent (PCE) is an important factor which is used to convert traffic volumes containing proportions of heavy good vehicles (HGVs) to a unify measure containing only passenger cars units (PCU). This paper uses large data base of real traffic raw data extracted from loop detector before being aggregated to estimate PCEs. These detectors are located on the M25 and the M42 motorway sites in the United Kingdom. The selected sites represent basic freeway segments as they are far away from the influence of entrance (on ramp) and exit (off ramp) sections. The data are filtered properly so as to estimate passenger car equivalents (PCEs) using lagging headway method for close following situations at different speed ranges. The results suggest that for the same location, the equivalency factors are varies significantly based traffic speed. However, it is proved that such variation with traffic speed is influenced by the differences in lengths between HGVs and cars. Regression models have also been developed linking the PCEs with traffic speed.展开更多
文摘Maritime transportation, widely used both in international transport of goods and touristic purposes, has been identified as a significant source of ultrafine particles (UFP). In-land passenger ferry is a source of UFP far less addressed;however, in locations with relatively high frequency of this transportation mode, it is expected that they contribute to an increase of their concentration. Moreover, the negative effects of UFP on human health and environment are known and therefore, monitoring UFP produced by ferries is vital to assess the degree of exposure of who work or live close to ferries’ terminals or downwind to their cruising path. This work aims to study the influence of in-land ferries activities on UFP in the urban/suburban areas near ferries’ terminals and downwind across the cruising path. The UFP monitoring campaign was carried out from September to December 2018 for 19 non-consecutive periods. The sampling sites were chosen in order to maximize measurements under downwind conditions and allow the association between ferry operation and UFP concentration response. Based on data collected, correlation analysis was performed between ferry’s traffic and particle number counting (PNC) of UFP, and also with meteorological variables. Results show an increase in PNC ranging from 25 to 197% during the third minute around a ferry movement and are moderate to positive significant correlations between PNC values and the number of ferry operations (r = 0.79 to r = 0.94), showing that UFP emitted by in-land ferries contributes to PNC increase. Moreover, negative correlations (r = -0.85 to r = -0.93) between PNC and wind intensity were also found.
文摘The purpose of this paper is to introduce an innovative methodology in shipping investment evaluation based on simulation of a project cash flow. It concerns a complementary approach to current practices and its aim is to provide more information mainly to ship-owners that consider the feasibility of deploying Ro-Ro Passenger ferries. The paper examines a typical semi-conventional RoPax ferry operating in the Aegean Sea. It addresses important economic, operational and procedural issues concerning risk evaluation. The current status is that risk is a notion still strange to main stakeholders. The Greek practice in performing a feasibility study for a project draws on investor＇s experience and feeling aided by a preliminary economic study. The main thesis of this paper is that there are alternative techniques to evaluate investment risk and measure profitability of a project. A Monte Carlo simulation in collaboration with a typical Ro-Ro cash-flow model is implemented to reveal the extent of risk and provide a useful tool for the assessment of future investments in Greek Short Sea Shipping.
文摘Passenger car equivalent (PCE) is an important factor which is used to convert traffic volumes containing proportions of heavy good vehicles (HGVs) to a unify measure containing only passenger cars units (PCU). This paper uses large data base of real traffic raw data extracted from loop detector before being aggregated to estimate PCEs. These detectors are located on the M25 and the M42 motorway sites in the United Kingdom. The selected sites represent basic freeway segments as they are far away from the influence of entrance (on ramp) and exit (off ramp) sections. The data are filtered properly so as to estimate passenger car equivalents (PCEs) using lagging headway method for close following situations at different speed ranges. The results suggest that for the same location, the equivalency factors are varies significantly based traffic speed. However, it is proved that such variation with traffic speed is influenced by the differences in lengths between HGVs and cars. Regression models have also been developed linking the PCEs with traffic speed.
