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581.
Comment by John R. Clark Comment by Kem Lowry Comment by Stephen B. Olsen Response by Jens Sorensen 相似文献
582.
B. Nolan 《Maritime Policy and Management》2013,40(2):77-88
Drinking among seafarers is an age-old and insufficiently studied problem. This paper is not concerned with alcoholism but with normal social drinking, its effects on suicide and accident rates, and its considerable value as an integrating factor in shipboard life. The author distinguishes sharply between sea-drinking and port-drinking and summarizes the research that relates personality traits, particularly dependence, to the use and abuse of alcohol. 相似文献
583.
Vertical distribution of sound scattering layers were observed using bottom deployed acoustic doppler current profilers (ADCP) during early spring of 1996 and autumn of 1997 in the Gullmarsfjord on the Swedish west coast. Variations in relative backscatter were interpreted in relation to horizontal water velocities, oxygen saturation as well as differences in the light, salinity and temperature regimes. Net catches revealed that much of the backscatter below 20-m depth was associated with the presence of krill, principally Meganyctiphanes norvegica.Horizontal currents seemed to influence the migration and distribution of krill, which showed weak vertical migration patterns with low abundance during periods of strong intermediate in- and outflows, while during periods with weaker currents, a more regular diel migration occurred. Horizontal water velocities >5 cm s−1 seemed to have the potential to decrease the peak in the backscatter profile. Mean vertical migration rates of krill was 1 cm s−1, while maximum vertical migration rates were estimated to be 2.5–3 cm s−1. The range of the vertical migration was different in 1997 due to severe oxygen deficiency in the bottom water, which prevented the krill from descending >80 m. The commencement of vertical migration correlated closely to the seasonal light conditions. The descent was immediately triggered by sunrise, while ascent occurred with a delay of about 1 h at sunset. 相似文献
584.
One of the major barriers to addressing complex social–ecological issues through integrated coastal management (ICM) is a lack of intergovernmental coordination and cooperation (horizontal and vertical fragmentation). This article describes an effort to overcome the barriers to ICM in Sri Lanka by fostering intergovernmental collaboration and initiating adaptive governance to restore one town, Hikkaduwa, and its associated marine protected area (MPA) and coastal zone habitats. Administrators from 12 national and local governmental agencies that are responsible for aspects of coastal management in the town of Hikkaduwa participated in a series of formal and informal workshops and a week-long tour of ICM projects in the Philippines. Outcomes demonstrate that these informal and formal meetings, workshops, and travel experiences fostered trust, social capital, and attitudinal organizational commitment (AOC). The experiences motivated members to overcome vertical and horizontal governance fragmentation through the formation of an independent intergovernmental committee for the restoration of Hikkaduwa into a sustainable and resilient community. ICM activities undertaken by the newly formed organization suggest that internal leadership capacity, effective local–national partnerships, explicitly linked ecological–economic projects, and long-term commitment are necessary conditions for success. Overall, attainment of sustainability and resilience through successful ICM should be thought of as a journey and not a destination. 相似文献
585.
Timothy B. Werner Luis Paulo Pinto Guilherme Fraga Dutra Paulo Gustavo Do Prado Pereira 《Coastal management》2013,41(1):99-108
The Abrolhos bank, an area of continental shelf off the coast of Bahia, Brazil, has the most biologically diverse coral reefs in the entire southern Atlantic Ocean. The coral reefs and nearby coastal ecosystems constitute a global conservation priority and are the target of the Abrolhos 2000 project, initiated by Conservation International as part of its global marine conservation strategy. Although portions of the Abrolhos reefs are located within a marine park, they are not afforded adequate protection due to insufficient conservation resources and a failure to be part of a broader integrated coastal management program. Through partnerships with government agencies, nongovernmental organizations, local communities, the private sector, and other stakeholders, Abrolhos 2000 is working to provide these needs while establishing local capacity for conserving coastal and marine ecosystems. The project's initial successes provide examples of useful strategies for making integrated coastal management work in the context of emerging economies. 相似文献
586.
Intermodal road-rail freight transport works best within markets with relatively large flows occurring over long distances, which corresponds poorly to the current demand for transport in the European Union. The purpose of this paper is to compare the capabilities of conventional European intermodal transport, with special reference to the competitiveness in markets with small flows over short distances, and to explore innovative concepts. Using a technological systems approach, key functions are identified as being the inducement and blocking mechanisms that affect the development and diffusion path of this 'small flows over short distances' (SFSD) system, providing a tool for empirical delineation of the system. These concepts are illustrated and analysed through a case study of the Swedish development project Light-combi. The results show that market and financial uncertainties, insufficient network connectivity and policies favouring the existing technology paradigm, severely hamper the development and diffusion of SFSD systems. 相似文献
587.
Children are an often overlooked and understudied population group, whose travel needs are responsible for a significant number
of trips made by a household. In addition, children’s travel and activity participation during the post-school period have
direct implication for adults’ activity-travel patterns. A better understanding of children’s after school activity-travel
patterns and the linkages between parents and children’s activity-travel needs is necessary for accurate prediction and forecasting
of activity-based travel demand modeling systems. In this paper, data from the 2002 Child Development Supplement of the Panel
Study of Income Dynamics is used to undertake a comprehensive assessment of the post-school out-of-home activity-location
engagement patterns of children aged 5–17 years. Specifically, this research effort utilizes a multinomial logit model to
analyze children’s post-school location patterns, and employs a multiple discrete–continuous extreme value model to study
the propensity of children to participate in, and allocate time to, multiple activity episode purpose-location types during
the after-school period. The results show that a wide variety of demographic, attitudinal, environmental, and others’ activity-travel
pattern characteristics impact children’s after school activity engagement patterns. 相似文献
588.
Conventional design methods require the lane marking patterns, which are painted on ground showing road users the permissible turning directions on different approach lanes, as exogenous inputs to define the traffic stream grouping for analysis. This predefined grouping of traffic movements may restrict the design of signal timings in the optimisation procedures. More recently, a lane-based design method has been developed to relax the lane markings as binary-type control variables in a mathematical programming approach. The lane marking patterns and the signal timings can then be optimised simultaneously in a unified framework. This paper presents an extension work to further relax the numbers of approach lane in traffic arms as new integer variables which can then be optimised to give optimal lane arrangement in various arms of a junction to manage the given traffic demands more efficiently. All well-defined signal timings variables in the phase-based approach as well as the lane marking and lane flow variables in the lane-based approach together with their governing constraints are all preserved in the new formulation for the reserve capacity optimisation of isolated signal-controlled junctions. 相似文献
589.
Maria Börjesson Jonas Eliasson 《Transportation Research Part A: Policy and Practice》2011,45(3):171-184
We investigate how passengers on long-distance trains value unexpected delays relative to scheduled travel time and travel cost. For scheduled services with high reliability and long headways, the value of delays is most commonly assumed to be proportional to the average delay. By exploring how the valuation of train delays depends on delay risk and delay length, using three different stated choice data sets, we find that the “average delay” approach does not hold: the disutility increases slower than linearly in the delay risk. This means that using the average delay as a performance indicator, a guide for operations planning or for investment appraisal will underestimate the value of small risks of long delays relative to large risks for short delays. It also means that estimated valuations of “average delay” will depend on the delay risk level: valuations will be higher the lower the risk levels in the study are. 相似文献
590.
B. Suh A. Frank Y. J. Chung E. Y. Lee Y. H. Chang S. B. Han 《International Journal of Automotive Technology》2011,12(1):131-139
This research concerns the design of a powertrain system for a plug-in parallel diesel hybrid electric bus equipped with a
continuously variable transmission (CVT) and presents a new design paradigm for the plug-in hybrid electric bus (HEB). The
criteria and method for selecting and sizing powertrain components equipped in the plug-in HEB are presented. The plug-in
HEB is designed to overcome the vulnerable limitations of driving range and performance of a purely electric vehicle (EV),
and it is also designed to improve the fuel economy and exhaust emissions of conventional buses and conventional HEBs. Optimization
of the control strategy for the complicated and interconnected propulsion system in the plug-in parallel HEB is one of the
most significant factors for achieving higher fuel economy and lower exhaust emissions in the hybrid electric vehicle (HEV).
In this research, the proposed control strategy was simulated to prove its validity using the ADVISOR (advanced vehicle simulator)
analysis simulation tool. 相似文献