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31.
Australia port reform initiatives have taken on a variety of forms — from out-right sale and transfer of ownership, to the sale of particular assets of infrastructure or services, or to long-term lease arrangements; or in some cases state governments, unable to relinquish control, have opted for corporatization or commercialization strategies. Reform is driven by the belief that ownership impacts on efficiency and efficiency is perceived to suffer if governments either retain ownership or direct control. As a result a major aim of reform is to either remove or distance governments from day to day port operations. The sale of ports removes government control outright and privatized ports are subject to identical regulatory constraints as any company in the private sector. But corporatization strategies are such that government ownership is retained and ports have been transformed into statutory state owned corporations. Effectiveness of this strategy requires legislation to be such that port corporations are free to operate like their private sector counterparts. To date this has not occurred and some serious impediments are emerging which are embedded in legislation and which, rather than reduce, have indeed, increased government control. 相似文献
32.
The potential for improving the fuel economy of conventional, gasoline-powered automobiles through optimized application of recent technology advances is analyzed. Results are presented at three levels of technical certainty, ranging from technologies already in use to technologies facing technical constraints (such as emissions control problems) which might inhibit widespread use. A fleet-aggregate, engineering-economic analysis is used to estimate a range of U.S. new car fleet average fuel economy levels achievable given roughly 10 years of lead time. Technology cost estimates are compared to fuel savings in order to determine likely cost-effective levels of fuel economy, which are found to range from 39 miles per gallon to 51 miles per gallon depending on technology certainty level. The corresponding estimated increases in average new car price range from $540 to $790 (1993$). Estimated fuel savings payback times average less than 3 years and the cost of conserved energy averages $0.50 per gallon, indicating that these levels of fuel economy improvement are cost-effective over a vehicle lifetime. A vehicle stock turnover model is used to project the reductions in gasoline consumption and associated emissions that would follow if the estimated fuel economy levels are achieved. Potential trade-offs regarding vehicle performance, safety, and emissions are also discussed. 相似文献
33.
While various forms of social difference (e.g. gender, age, race/ethnicity, and class) have been engaged in the active school travel (AST) and children’s independent mobility (CIM) literatures, one form has gone largely unconsidered: disability. Disregard for disability within these literatures is troubling, as it leaves children’s experiences of disability associated with independent mobility and school travel unquestioned, which in turn helps to allow their experiences of exclusion to persist. This paper presents a systematic review of the AST and CIM literatures that was undertaken with a view to providing insight into three questions. (1) To what extent is disability considered in the literatures in comparison to other forms of social difference? (2) How is disability engaged? (3) How could disability be approached differently such that experiences of children (and their households) living with disability are better accounted for moving forward (e.g. provided with equitable travel/mobility options)? Following a detailed consideration of the systematic review process, this paper presents figures and tables showing the extent to which disability has been considered in the two literatures in relation to other forms of social difference. To show how transport scholars and others are engaging disability, 29 studies were identified for in-depth, qualitative review. These studies are summarized and then discussed in relation to their geographic focus, the forms of disability they considered, their treatment of children’s perspective and agency, and the disability perspectives they employed. It is suggested that disability and its relationships with other forms of social difference, as well as the largely unquestioned normalcy of children’s disability experiences, warrant further inquiry within the AST and CIM literatures. We propose that drawing upon a critical ableist studies perspective may be useful for any such inquiry due to its focus on ableism and normalcy, as well as its recognition of the complex intersectionality of disability experiences. 相似文献
34.
To assess the safety of navigation in muddy areas, a comprehensive captive manoeuvring model test program was executed. Based
on the results of this experimental program, a four-quadrant manoeuvring model was built with a separate set of coefficients
for each combination of under-keel clearance and mud layer characteristics. The disadvantage of this model is that only conditions
corresponding with the experimental ones can be simulated. A more consolidated mathematical model was needed. This was achieved
with the introduction of a fluidization parameter that determines the corresponding hydrodynamically equivalent depth above
a solid bottom. As a result, the under-keel clearance dependency of a given mathematical manoeuvring model can be reformulated
in such way that the effect of any realistic muddy condition is included. In this article, the modelling of the hull forces,
the propeller thrust and torque, and the forces acting on the rudder will be discussed. 相似文献
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36.
Montecinos Julio Ouhimmou Mustapha Chauhan Satyaveer Paquet Marc Gharbi Ali 《Transportation》2021,48(5):2401-2431
Transportation - A sharing logistics platform for less-than-truckloads could increase efficiency in city pickup and last-mile deliveries under time window constraints by pairing (matching) truck... 相似文献
37.
AbstractThe European Union (EU) promotes gradual lifting of restrictions on foreign hauliers involved in domestic road transport of goods (cabotage), and a major deregulation was scheduled in 2014. Due to complaints from several member states facing competition from new EU-countries with lower labour costs, this process was postponed until 2015. An important aspect related to such a deregulatory reform includes potential consequences for transport safety and accident risk factors. The main aims of the current paper are therefore to examine the potential transport safety outcomes of increasing internationalization of domestic road haulage, and to examine potential accident risk factors of foreign hauliers. This is done by reviewing the research literature. This paper shows that the heavy goods vehicle (HGV) accident risk varies with a factor of up to 10 in European countries, and that the accident risk of foreign HGVs is approximately two times higher than that of domestic HGVs in the studied European countries. The paper points to several risk factors and concludes that better data on accident risk and risk factors must be gathered in order to enable European authorities to correctly analyse and respond to this important traffic safety challenge. 相似文献
38.
Bahareh SehatzadehRobert B. Noland Marc D. Weiner 《Transportation Research Part A: Policy and Practice》2011,45(8):741-754
To explain walking propensity or frequency, empirical studies have generally used two sets of explanatory variables, namely, socio-demographic variables and built environment variables. They have generally shown that both socio-demographic characteristics and built environment characteristics are associated with walking propensity. We examine the traditional walkability variables that encompass density, mix of uses, and network connectivity in New Jersey, using a statewide sample including an oversample of Jersey City. We estimate a two-stage least squares model using a conditional mixed process that combines an ordered probit model of walking frequency in the second stage based on a truncated regression of car ownership in the first stage. Our results show that built environment variables have some small effects, mainly from better network connectivity associated with increased walking frequency. One of our key findings is that built environment features also work indirectly via how they influence car ownership. In general, we find sufficient evidence that suggests fewer cars are owned in areas with more walkable built environment features. The other key variable that we control for is whether a household owns a dog. This also proved to be strongly associated with walking suggesting that dog ownership is a necessary control variable to understand the frequency of walking. 相似文献
39.
Abstract State coastal zone management programs are responding to the potential impacts of accelerated sea level rise through a wide range of activities and policies. This article provides a brief overview of the Coastal Zone Management Act and other federal laws that provide the basis for coastal state regulatory activities. It surveys the level of response to sea level rise by state coastal management programs in 24 marines coastal states, from formal recognition to implementation of policies addressing the issue. Individual state CZMP responses and policies that have been implemented or proposed are categorized. The adaptation of sea level rise to ongoing institutional objectives is discussed and policy constraints and trends are summarized. 相似文献
40.
In 1997 the Australian government introduced reform measures aimed at improving the efficiency and cost effectiveneess of the Auistralian maritime sector. These measures are part of an ongoing reform programme initiated in the early 1980s; but despite concerted efforts by a succession of governments and the payout of high labour redundancy costs the problems of inefficiency, high costs and low profitability persist. This paper focuses on the structure and mechanism of the policy making processes that have attempted to deal with the problem of making the Australian national flag fleet efficient and competitive. It does so because it is a fundamental tenet of the paper that it is the process of policy making that so frequently—if not invariably—determines policy content and outcomes. 相似文献