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721.
Attitudes towards public transport (PT) in New Zealand’s three largest cities (Auckland, Wellington, and Christchurch) were
examined in a cross-sectional survey of drivers. A measure of prejudice to PT was developed to assess the strength and nature
of attitudinal differences. Auckland residents had the highest levels of PT prejudice while Wellington residents had the lowest,
and these differences were not related to demographic differences between the samples. Direct contact with PT was associated
with reduced levels of PT prejudice, but measures of indirect contact, beliefs about using PT, and environmental attitudes
were stronger predictors of PT prejudice scores. Controlling for these variables resulted in the difference in PT prejudice
levels between Wellington and Christchurch becoming non-significant, while the differences between Auckland and the other
two cities remained. This suggests that the difference between Wellington and Christchurch was primarily based on social norms
regarding PT prejudice, while quality of service was a factor in the difference between Auckland and the other two cities.
It is suggested that campaigns promoting PT ridership should focus both on the quality of service and on presenting PT usage
as socially normal. 相似文献
722.
The nature of the global economy is one of dynamic change. Shipping is a service industry with its demand related to changes in international trade levels and patterns. As a consequence shipping is subject to sometimes unpredictable swings in demand so that the operator is required to make strategic planning decisions while navigating through boom or bust environments. While boom economies generate rising freight rates which are welcomed and encourage investment, ship operators may also have to face falling freight demand and declining freight rates that may have significant impact on profitability, often falling to uneconomic levels for extended periods. In such a period of uncertainty and declining profitability management will make operational decisions to reduce costs. However, shipping lines operate in a market environment so any decisions made to rationalize the trade may have significant long-term competitive implications. For example, traditional micro economic theory might suggest that the prudent strategy to adopt would be to close down the operation and reopen when the market conditions improve. In a world of certainty or when costs of taking this action are zero, this would be a valid strategy. However, because of fear of competitors taking up a line's market share if the shipping company exits, even temporarily, this strategy cannot be valued simply in terms of shut-down and start-up costs. A further consideration is the fact that standard capital budgeting techniques, such as Net Present Value (NPV), cannot incorporate the flexibility to respond to new information and strategic responses explicitly into their investment analysis. This paper will demonstrate the use of Real Option Analysis (ROA) to provide guidelines for decisions about closing operations in adverse market conditions. 相似文献
723.
The container terminal community 总被引:1,自引:0,他引:1
Over the past 30 years, technological developments have not only affected the design and operation of the port function, but also the organizational and institutional relationships within the port community. Two inter-organizational interaction models are presented, drawing on the findings of over 200 in-depth interviews with senior managers representing terminal operators, shipping lines, feeder operators, ship agents, road hauliers, freight forwarders and shippers serving the UK?Far East trade. The first model represents a breakbulk berth of the 1960s and the second a modern container terminal community. In comparing the models, it is shown that containerization has transformed the fragmented breakbulk operation of the 1960s into the cohesive container terminal community that today facilitates port operations. The paper concludes by examining trends in key inter-organizational relationships in the community and the emergence of eBusiness. 相似文献
724.
This study examines the effects of certain closed areas to the trawl fishery on some Rajidae species and small-spotted catshark in the southern area of the Bay of Biscay. The results are based on abundance index (number/haul) and catch length composition obtained from a series of bottom trawl surveys carried out in the area (1993–2005). Abundance trends are similar considering or not closed areas, but with much lower values excluding closed areas. The length distributions revealed that in some of the species like Scyliorhinus canicula the larger specimens were the most affected by this decrease in number. Finally, the effects and consequences of one of these marine protected areas (MPAs), an artificial reef were examined in more detail for all the fishes and invertebrates. The analysis of the yield series showed an increase in total biomass after the placement of the reefs not only for S. canicula and rays but also teleosts fishes like Pagellus acarne, Trachurus trachurus, Mullus surmuletus and Trachinus draco and particularly invertebrates (sea urchins). On the contrary, the main target species of the trawl fishery (hake, monkfish and megrim among others) did not increase. 相似文献
725.
We examined the influence of the Mackenzie River plume on sinking fluxes of particulate organic and inorganic material on the Mackenzie Shelf, Canadian Arctic. Short-term particle interceptor traps were deployed under the halocline at 3 stations across the shelf during fall 2002 and at 3 stations along the shelf edge during summer 2004. During the two sampling periods, the horizontal patterns in sinking fluxes of particulate organic carbon (POC) and chlorophyll a (chl a) paralleled those in chl a biomass within the plume. Highest sinking fluxes of particulate organic material occurred at stations strongly influenced by the river plume (maximum POC sinking fluxes at 25 m of 98 mg C m− 2 d− 1 and 197 mg C m− 2 d− 1 in 2002 and 2004, respectively). The biogeochemical composition of the sinking material varied seasonally with phytoplankton and fecal pellets contributing considerably to the sinking flux in summer, while amorphous detritus dominated in the fall. Also, the sinking phytoplankton assemblage showed a seasonal succession from a dominance of diatoms in summer to flagellates and dinoflagellates in the fall. The presence of the freshwater diatom Eunotia sp. in the sinking assemblage directly underneath the river plume indicates the contribution of a phytoplankton community carried by the plume to the sinking export of organic material. Yet, increasing chl a and BioSi sinking fluxes with depth indicated an export of phytoplankton from the water column below the river plume during summer and fall. Grazing activity, mostly by copepods, and to a lesser extent by appendicularians, appeared to occur in a well-defined stratum underneath the river plume, particularly during summer. These results show that the Mackenzie River influences the magnitude and composition of the sinking material on the shelf in summer and fall, but does not constitute the only source of material sinking to depth at stations influenced by the river plume. 相似文献
726.
727.
728.
F. Bayat A. Fadaie Tehrani M. Danesh 《International Journal of Automotive Technology》2012,13(5):809-816
Proportional hydraulic valves (PHVs) have remarkable applications in different branches of industry. These valves can control an oil hydraulic system. One of the most important factors affecting a proportional solenoid (PS) is the geometry that affects its magnetic force with respect to its plunger position. Other effective factors include the size of the air gap, the current density and various soft magnetic materials that have different B-H (flux density versus field intensity) curves. Electromagnetic analysis (EMA) is used to enhance the reliability and accuracy of the PS and to reduce the total cost. In this paper, a range of PSs are software package with different air gaps, dimensional parameters, current densities and soft magnetic materials. The magnetic flux density and force are calculated using a finite element method (FEM), and the results are compared with the experimental results of an actual PS. 相似文献
729.
The mechanical characteristics of four materials used in automotive exhaust systems have been compared after an aging treatment to evaluate the combined effects of thermo-mechanical fatigue and corrosion. For this purpose, an experimental aging procedure has been developed. This procedure is composed of chemical, thermal and mechanical cycles, which are combined and repeated to simulate the actual operating conditions of automotive exhaust systems. Three austenitic steels (AISI 309, AISI 316Ti, and AISI 321) and a nickel-based alloy (Inconel 625) are tested. The results show that Inconel 625 and AISI 309 are less affected by the aging process than the other materials. 相似文献
730.
In Europe, ports are confronted with a closer integration in the maritime and shipping industries. The co-operation agreements can take several forms such as alliances and mergers among shipping lines, conferences, involvement of shipping companies in terminal management, and extending interests in inland transport of shipping companies. In this paper we give a brief overview of these different types of agreement and we examine the consequences of this evolution of the market structures in which ports and shipping companies have to operate. More specifically, attention goes to the competitive position of the port in this new environment. It is clear that the role of the port and the port authorities has to be redefined to guarantee that it remains a fully fledged player in this fast evolving integrated market. 相似文献