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81.
Julián Pando Andres Araujo Francisco Javier Maqueda 《Maritime Policy and Management》2013,40(2):67-87
Recent technological developments in maritime transport, particularly in container shipping and larger vessels, are having major repercussions at ports the world over. The latest wave of innovations has increased the level of competition in maritime transport, in particular in port activities. Shippers have many more alternatives available, something that tends to increase the hinterland of each port, precisely by reducing captive hinterlands. Ports are now generally moving towards formulas in which private initiative has a bigger role to play. Increases in competition combined with growth in private initiatives highlight the usefulness of marketing tools in two ways. Externally, because they help to achieve throughputs from remote points of origin and destination, and internally, by aiding the proper coordination of business and organizational activity at a commercial port. The present paper is a transversal study of the current situation of marketing and quality tools at major ports, including the opinions of a range of port commercial and marketing managers. We have also tried to describe the differentiated groups to be found at ports, as a useful methodology for identifying the nearest competition or ports with similar characteristics. 相似文献
82.
Katia Arons Patricia Ayn Hans-Jürgen Hirche Ralf Schwamborn 《Journal of Marine Systems》2009,78(4):582
The objective of the present study was to verify possible spatial, seasonal, and inter-annual changes in the zooplankton off Paita (northern Peru), an upwelling area located closely to the limits of cold Humboldt Current and warm Equatorial Surface Waters. Zooplankton was sampled at subsurface on 53 occasions from August 1994 to December 2004 at four stations located 2 to 30 km offshore with a WP-2 net (300 µm). Extremely high surface water temperatures combined with low salinities were observed during the 1997/98 El Niño up to 29.0 °C) and in April 2002 (up to 25.0 °C). Temperatures more than 2 °C above monthly average were also observed in October 1994, in April 2000, and in November 2004. Significant trends were observed for oxygen concentration (increase) and several horizontal and vertical gradients. Among the copepods (72% of all individuals), the most abundant species were Paracalanus parvus (28%), Acartia tonsa (26%), and Calanus sp. (10%). The strong 1997–98 El Niño (EN) event led to drastic changes in species composition that were reversed during the 1998–99 La Niña (LN) event. Community parameters such as total abundance, diversity, equitability and species richness displayed marked variations associated with the 1997–98 EN and long-term trends. Long-term trends were significant for several vertical and horizontal temperature and oxygen gradients, indicating an increase in upwelling intensity at the shelf during the study period. 10-year-trends were also significant for total zooplankton abundance (increase) and community evenness (J, decline). Our data confirmed the importance of the weak EN in 2002/03 for the study region. Within the trend of increasing zooplankton abundance, a sharp step or shift was observed from 1999 to 2000. When using sequential t-tests to detect shifts in (x + 1) transformed abundance data, a significant rupture was found between the last sampling in 1999 and the first sampling in 2000. Also, a substantial decrease in diel variability occurred after 1999, probably due to changes in vertical migration patterns. The considerable increase in zooplankton abundance over the study period, the ENSO effect, and the 1999–2000 transition are discussed with regard to synchronicity with other zooplankton time series. The present study contributes with the first evidence from an important area located in the Humboldt Current for synchronous trends and changes that were previously observed elsewhere in the Pacific. Our results demonstrated the importance of long-term zooplankton monitoring studies in upwelling areas, and confirms the idea of dramatic changes in pelagic ecosystem structure occurring in the East Pacific. 相似文献
83.
Juan M. Barragán Muñoz 《Coastal management》2013,41(3):137-156
The article is divided into three clearly defined sections. The first outlines the Brazilian National Coastal Zone Management Plan. The second offers a critical assessment of its introduction. To conclude, some general considerations are made. In this way, the author aims to achieve two objectives: to disseminate the aforementioned plan and offer a critical opinion of it. 相似文献
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86.
Late Holocene history of the rainfall in the NW Iberian peninsula—Evidence from a marine record 总被引:2,自引:0,他引:2
P. Bernrdez R. Gonzlez-lvarez G. Francs R. Prego M.A. Brcena O.E. Romero 《Journal of Marine Systems》2008,72(1-4):366
This study reconstructs climatic variability over the last 4700 yr in the NW Iberian Peninsula on the basis of lithological, sedimentological, biogeochemical, micropaleontological (diatoms and biosiliceous compounds) and AMS 14C analyses conducted in a gravity core retrieved from the Galician continental shelf. The core was recovered at the Galicia Mud Patch, a muddy sedimentary body highly influenced by the terrestrial supply of the Miño and Douro rivers, and thus controlled by the rainfall variations over the catchment area. River plume transports the lithogenic and continental-derived compounds to the shelf area allowing us to recognize several periods of terrestrial/marine influence. These periods are well correlated with the lithological units identified. Coarser sediments, high values of Ca/Al, low values of Fe, Al and lithogenic Si (LSi) are representative of the marine-influenced periods. These stages are related to dry conditions and winds coming from the NE under a NAO positive-like phase.Terrestrial-influenced stages are characterized by muddy sediments, with high content of Fe, Al and LSi, freshwater and benthic diatoms, continental-derived organisms (crysophycean cysts and phytoliths) and high amount of land-derived organic matter as reported by the C/N ratios. The influence of NAO positive- and NAO negative-like periods and solar activity are the two mechanisms quoted to explain the climatic variability during the last 4700 years.Proxies for the lithogenic input and terrigenous content (non-organic material) show an increase at around 2000–1800 cal. yr BP, linked to the warmer conditions and high precipitation patterns during the Roman Warm Period, and soil erosion due to forest degradation and other anthropic activities. A strong river flow event is recorded in shelf sediments during 800–500 cal. yr BP. A pervasive NAO negative-like period, and the high irradiance registered during the Grand Solar Maximum (GSM) controlled the precipitation and induced a high run-off and riverine influx during this event. 相似文献
87.
Ana Laverón-Simavilla Victoria Lapuerta Sebastián Franchini Angel Sanz 《Journal of Marine Science and Technology》2008,13(3):190-206
A study of a boat's motion is carried out in order to analyze the aerodynamic properties of the optimal sail for obtaining the maximum velocity when sailing to windward. The mechanics study shows the optimal C L and C D for a given sail and how the shape of the aerodynamic polar of the sail should be. A parametrical analysis of the aerodynamics of a sail is then carried out varying the maximum camber, position of the maximum camber in the chord direction and position of the maximum camber in the mast direction. The parametric analysis is done numerically with a vortex lattice method (VLM) and experimentally in a wind tunnel. The results show that the influence of the relevant parameters studied can be reduced to the variation of two parameters, A and B, defining the polar of the sail, C D = B + A 2 C L 2; and the influence of parameters A and B on the maximum VMG obtainable are calculated. 相似文献
88.
89.
Muhammad Marizwan Abdul Manan András Várhelyi Ali Kemal Çelik Hizal Hanis Hashim 《国际交通安全学会研究报告》2018,42(4):207-220
This study aims to determine risk factors contributing to traffic crashes in 9,176 fatal cases involving motorcycle in Malaysia between 2010 and 2012. For this purpose, both multinomial and mixed models of motorcycle fatal crash outcome based on the number of vehicle involved are estimated. The corresponding model predicts the probability of three fatal crash outcomes: motorcycle single-vehicle fatal crash, motorcycle fatal crash involving another vehicle and motorcycle fatal crash involving two or more vehicles. Several road characteristic and environmental factors are considered including type of road in the hierarchy, location, road geometry, posted speed limit, road marking type, lighting, time of day and weather conditions during the fatal crash. The estimation results suggest that curve road sections, no road marking, smooth, rut and corrugation of road surface and wee hours, i.e. between 00.00 am to 6 am, increase the probability of motorcycle single-vehicle fatal crashes. As for the motorcycle fatal crashes involving multiple vehicles, factors such as expressway, primary and secondary roads, speed limit more than 70 km/h, roads with non-permissible marking, i.e. double lane line and daylight condition are found to cause an increase the probability of their occurrence. The estimation results also suggest that time of day (between 7 pm to 12 pm) has an increasing impact on the probability of motorcycle single-vehicle fatal crashes and motorcycle fatal crashes involving two or more vehicles. Whilst the multinomial logit model was found as more parsimonious, the mixed logit model is likely to capture the unobserved heterogeneity in fatal motorcycle crashes based on the number of vehicles involved due to the underreporting data with two random effect parameters including 70 km/h speed limit and double lane line road marking. 相似文献
90.
A. Badea A. Furones F. J. Páez C. González 《International Journal of Automotive Technology》2010,11(5):711-720
Pedestrians are the most vulnerable users of public roads and represent one of the largest groups of road casualties; their
death rate around the world due to vehicle-pedestrian collisions is high and tending to rise. In Spain, as in other countries
of the European Union, steps have been taken to reduce the number and consequences of such accidents, with encouraging results
in recent years. A key to countering this concern is the accident research activity that has obtained remarkable achievements
in different fields, especially when multidisciplinary approaches are taken. This paper describes the development of a multivariate
model that is able to detect the most influential parameters on the consequences of vehicle-pedestrian collision and to quantify
their impact on pedestrian fatality risk. First, an accident database containing detailed information and parameters of vehicle-pedestrian
collisions in Madrid has been developed. The accidents were investigated on the spot by INSIA accident investigation teams
and analyzed using advanced reconstruction techniques. The model was then developed with two components: (1) a classification
tree that characterizes and selects the explanatory variables, identifying their interactions, and (2) a binary logistic regression
to quantify the influence of each variable and interaction resulting from the classification tree. The whole model represents
an important tool for identifying, quantifying and predicting the potential impact of measures aimed at reducing injuries
in vehicle-pedestrian collisions. 相似文献