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171.
Stated choice experiments have proven to be a powerful tool in eliciting preferences across a broad range of choice settings. This paper outlines the elements of a group-based experiment designed for interdependent urban freight stakeholders, along with the procedure to administer the questionnaire sequentially. The focus is on the design of a computer-assisted personal survey instrument and the value in disseminating the details of a new approach to design and collect stated choice data for interacting agents. The paper also discusses how to specify a reference alternative, and then how to recruit appropriate real-market or representative decision-making group members to participate in a subsequent phase of the survey, which incorporates the reference alternative and contextual information from an initial phase. The empirical strategy, set out in some detail, provides a new framework within which to understand more fully the role that specific attributes, such as variable user charges, influencing freight distribution chains might play, and who in the supply chain is affected by specific attributes in terms of willingness to pay for the gains in distribution efficiency.
Andrew CollinsEmail:
  相似文献   
172.
In recent years, external pressures on maritime businesses have increased their need to employ high calibre personnel, educated to respond effectively to these pressures. Set against this requirement, the onus of acquiring a university education has shifted to the individual, as state subsidies to individuals seeking to undertake higher education in British universities have declined, and many corporate training programmes have been aimed at meeting the needs of an organization rather than the individuals within them. If the future supply of graduates is to match ongoing industrial requirements, one needs to understand why students enrol on particular courses, and how importantly they perceive employment considerations to be when making their decisions. This paper reports on a survey of why students at several British universities chose to enrol on undergraduate courses in Maritime Business, and considers the implications of its findings for ensuring that an adequate supply of suitably educated graduates will continue to be available to meet industrial needs.  相似文献   
173.
Variations in oxygen conditions below the permanent halocline influence the ecosystem of the Baltic Sea through a number of mechanisms. In this study, we examine the effects of physical forcing on variations in the volume of deep oxygenated water suitable for reproductive success of central Baltic cod. Recent research has identified the importance of inflows of saline and oxygenated North Sea water into the Baltic Sea for the recruitment of Baltic cod. However, other processes have been suggested to modify this reproduction volume including variations in timing and volume of terrestrial runoff, variability of the solubility of oxygen due to variations in sea surface temperature as well as the influence of variations in wind stress. In order to examine the latter three mechanisms, we have performed simulations utilizing the Kiel Baltic Sea model for a period of a weak to moderate inflow of North Sea water into the Baltic, modifying wind stress, freshwater runoff and thermal inputs. The model is started from three-dimensional fields of temperature, salinity and oxygen obtained from a previous model run and forced by realistic atmospheric conditions. Results of this realistic reference run were compared to runs with modified meteorological forcing conditions and river runoff.From these simulations, it is apparent that processes other than major Baltic inflows have the potential to alter the reproduction volume of Baltic cod. Low near-surface air temperatures in the North Sea, the Skagerrak/Kattegat area and in the western Baltic influence the water mass properties (high oxygen solubility). Eastward oriented transports of these well-oxygenated highly saline water masses may have a significant positive impact on the Baltic cod reproduction volume in the Bornholm Basin.Finally, we analysed how large scale and local atmospheric forcing conditions are related to the identified major processes affecting the reproduction volume.  相似文献   
174.
This paper presents an overview of the globalization process and its implications for international maritime distribution. Globalization is an imprecise term used to designate a way of looking at the world. It has no generally accepted definition; different commentators emphasize different aspects according to their individual predilections. Yet most are agreed that it represents a further stage in the evolution of international relations and, in particular, international business. Globalization is a break with the past, challenging accepted modes of thought and their translation into business practice. It is a post-modern phenomenon broadly characterized by, amongst other things, co-operation rather than competition, by flexible accumulation rather than centralized mass production, and by the compression of space and time. Networks, both conceptual and physical, play a key role in the globalization process by defining the relationships between individual elements such as producers, retailers, consumers etc and the flows of information and materials that pass among them. Hence ships, transportation and logistics are themselves also central to the process. This paper describes the process of globalization and goes on to consider the implications of the supply chain approach to international logistics and distribution for traditional maritime industry.  相似文献   
175.
Combating illegal and destructive resource exploitation in the Coral Triangle is central to ensuring the long-term effective management of fisheries, marine protected areas, and climate change adaptation efforts. This article presents results of an investigation of the perceived level of local compliance and enforcement with marine resource rules and regulations and evaluates the effectiveness or potential for community-supported enforcement efforts in the Coral Triangle region. The findings are consistent with those of the literature on compliance and enforcement that any compliance and enforcement system must not only use deterrence, but also be perceived by fishers as being legitimate, fair, accountable and equitable and the need for developing a personal morality and a social environment that supports compliance. There is an opportunity to strategically build on shared value and cultural norms that can promote collaborative fisheries management as a mechanism to increase compliance through non-coercive efforts. Strengthening the long-term capacity for consistent delivery of local support to marine management and enforcement will increase local compliance rates through time.  相似文献   
176.
In this paper, we develop a general random utility framework for analyzing data on individuals’ rank-orderings. Specifically, we show that in the case with three alternatives one can express the probability of a particular rank-ordering as a simple function of first choice probabilities. This framework is applied to specify and estimate models of household demand for conventional gasoline cars and alternative fuel vehicles in Shanghai based on rank-ordered data obtained from a stated preference survey. Subsequently, the framework is extended to allow for random effects in the utility specification to allow for intrapersonal correlation in tastes across stated preference questions. The preferred model is then used to calculate demand probabilities and elasticities and the distribution of willingness-to-pay for alternative fuel vehicles.  相似文献   
177.
On cost-efficiency of the global container shipping network   总被引:1,自引:0,他引:1  
This paper presents a simple formulation in the form of a pipe network for modelling the global container-shipping network. The cost-efficiency and movement-patterns of the current container-shipping network have been investigated using heuristic methods. The model is able to reproduce the overall incomes, costs, and container movement patterns for the industry as well as for the individual shipping lines and ports. It was found that the cost of repositioning empties is 27% of the total world fleet running cost and that overcapacity continues to be a problem. The model is computationally efficient. Implemented in the Java language, it takes one minute to run a full-scale network on a Pentium IV computer.  相似文献   
178.
The present paper presents the necessary crack growth statistics and suggests stochastic models for a reliability analysis of the fatigue fracture of welded steel plate joints. The reliability levels are derived from extensive testing with fillet-welded joints for which the entire crack growth history has been measured, not only the final fatigue life. The statistics for the time to reach given crack depths are determined. Fracture-mechanics-derived crack growth curves are fitted to the measured experimental curves and the best fit defines the growth parameters involved for each test specimen. The derived statistics and distribution function for these parameters are used as variables in a Monte Carlo simulation (MCS). In addition a Markov model is developed as an alternative stochastic model. It is a Markov chain for which the discrete damage states are related to chosen crack depths in the material. This model works directly with the experimental time statistics. It is a “stochastic bulk approach” not involving any random variables or fracture mechanics modeling. Both models are fitted to the data base and scaled to in-service conditions. Both methods are compared and discussed. The aim is to provide data for the variables used in a MCS and to develop a Markov chain for fast reliability calculation, especially when predicting the most likely influence of numerous future inspections.  相似文献   
179.
180.
There is growing interest amongst both practitioners and researchers in the correlates of young adults’ driving-licence-acquisition. One aspect of the ongoing scholarly debate is whether taking part in online (i.e. virtual) activities may be associated with young adults feeling less need to drive and hence to acquire a driving licence. This paper addresses this issue by drawing on analysis of two distinct datasets. Both contain rich pseudo-diary instruments in which people indicate detailed characteristics of their unique online-activity profile. This includes both indicators of the types of online activities in which respondents participate, and a separate metric of internet-use intensity. The latter is defined in one dataset as the amount of time/week spent online, and in the other dataset the frequency of their internet use. On the basis of a set of multivariate regression analyses, a positive (i.e. complementary) cross-sectional relationship between young adults’ online activity and licence-holding was found. We find that young adults who use the internet are, net of confounding effects, more likely to hold a driving licence than otherwise identical young adults who do not use the internet. Both datasets show this type of effect, and it is robust across a range of model specifications, including multi-stage estimations to address cross-correlation between indicators of internet usage. In addition to the positive net statistical association, we also report several other noteworthy effects. Of the six effects associated with online-activity types that are directly comparable between the two datasets, we find that the correlation in the parameter estimates across the two datasets is 0.63. This suggests similar types of relationships across the two datasets. Also, in several (but not all) of our analyses we found an inverted ‘U’ shaped ceteris paribus relationship between intensity-of-internet-use and licence-holding. The positive net statistical association between internet use and licence-holding is a different relationship than previously reported in the literature, and therefore further research is needed to reconcile the differences (which are likely due at least in part to different methodological approaches and data resources). Further research is also needed to continue to resolve between the relative saliency of other hypothesised determinants of licence-holding (e.g. economic and socio-demographic explanators, as well as licence-acquisition regimes that vary by time and place).  相似文献   
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