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1.
Due to the burgeoning demand for freight movement in the era of e-commerce, freight related road safety threats have been growing in both urban and suburban areas, despite the improved general traffic safety over the past decades. The empirical evidence on how freight trucks related crashes are distributed across neighborhoods and correlated to spatially varying factors is, however, highly limited. This article uses data from the Los Angeles region in 2018 to analyze the spatial patterns of freight trucks related traffic crashes and examines the major factors that contribute to those patterns using spatial econometric models. Maps show that freight trucks related crashes are highly associated with major freight generators but less clustered than the overall traffic crashes. Results from the spatial Durbin model indicate that access to freight generators, economic attributes, land uses, road infrastructure, and road network variables all contribute to the spatial distribution of freight trucks related crashes. The findings could help transport planners understand the dynamics of freight trucks related traffic safety and develop operational measures for mitigating the impacts of growing goods movement on local communities.  相似文献   

2.
This paper suggests a flexible decision support framework for the strategic planning of a freight transport hub network in Greece. The proposed methodology treats practical aspects related to the optimal number, location and geographical covering of hubs, through the network analysis of interregional trade, based on original survey data for road freight flows during 2004–2012. The results offer insights into the hierarchical structure of the network and related investment priorities, as the hub role of a prefecture is found to be strongly influenced by high population densities and manufacturing specialization, and its location along highway corridors.  相似文献   

3.
This paper identifies and quantifies the impact of a major passenger alliance, between KLM and Northwest Airlines, on the cargo service characteristics of one of the partners, KLM. The hypothesis that the KLM/Northwest Airlines passenger alliance had led to a decline in the quantity and quality of cargo service connections is rejected, even though the first years of the alliance clearly indicate deteriorated cargo layover times. The number of possible connections and the inbound and total routing belly-hold capacity increased during the time-span considered for the research. Also, the cargo layover times eventually declined after an initial increase. Different samples of routes connecting through Minneapolis, Detroit, New York, and Chicago (the latter being KLM Cargo's hub where interlining with United Airlines is feasible) all demonstrate a consistent positive impact. Partner connections eventually outperformed interlining.  相似文献   

4.
Despite the fact that freight transport has a huge impact on the economy and the environment, Belgian datasets have always been scarce or restricted to very small a-spatial samples. Spatial data collected in Belgium for toll-paying trucks are here examined, and geographical structures and dynamics are extracted from this massive dataset. The originality of this dataset is its exhaustivity and its real-time approach: the location of all the trucks circulating in Belgium is collected every 30 s.The paper first relates to the methodology applied when using and transforming big data generated by On Board Units GNSS (cleaning, transforming and pre-processing). Second, it maps and comments on the movements (traffic) and stops of trucks within the whole country, providing a clear picture of the Belgian situation, useful for regional planners and logistics companies. Finally, the flows of trucks observed between Belgian locations enable the country to be divided into mathematical communities of places that interact the most. Analyses are performed for sub-categories based on the country of registration, underlining the spatial specificities of freight transit in Belgium. This exploratory spatial data analysis enables to reveal not only multi-level spatial structures associated with urban hierarchies and the transport infrastructure, but also firm locations or political organizations and to consider the complexity and interconnectivity of any measure taken for a more sustainable future. With a clear methodological framework to cope with the data pre-processing, this paper opens the way to various potential applications linked with freight transportation in Belgium.  相似文献   

5.
This paper provides a data based analysis of FedEx air freighter activities from selected hub locations. The basic idea is that air freighters have a set of range and payload parameters and their corresponding fuel burn depends on weight and distance. Data from 2011 to 12 (FlightAware) are used for 180,000 + flights on origin, destination and aircraft type. The particular aircraft vary widely in payload, but additional parameters may be derived from industry web sites and BTS. The research uses flight activity at hubs such as Memphis and Indianapolis (among others) and computes the aggregate distance flown on specific aircraft. The linkage between the hub and aggregate fuel use (assuming that the out bound flights are allocated to the hub) will give some quantifiable measures of the costs allocated to the hub. The paper examines particular aspects of the air freight system that are especially vulnerable to a spike in the costs of aviation fuel. These observations suggest that traffic to regional air express and air freight hubs is likely to respond in complex ways to fuel costs.  相似文献   

6.
适应现代物流理念的合肥铁路枢纽货运站布局规划   总被引:1,自引:0,他引:1  
运输市场竞争的加剧,要求铁路货运业务必须向现代物流服务转变。结合合肥经济、交通发展现状及规划,提出了完善优化合肥铁路枢纽货运站布局、合肥综合性货运站搬迁的必要性,对物流化合肥铁路枢纽货运站选址的原则、方案及结果进行详细分析。  相似文献   

7.
Published fares London–Amsterdam are used to examine the pricing practices of low-cost and legacy carriers when operating in a large and crowded market. We investigate two strategies of market segmentation involving the time before departure the ticket has been bought, inter-temporal segmentation, and the duration of the stay, implicit segmentation. We find inter-temporal price discrimination emerges as an important strategy for all pricing but the two legacy carriers involved, British Airways and KLM, differ in their use of stay restrictions; British Airways does not assign a specific role to the duration of stay, while KLM make use of such rules extensively in price setting.  相似文献   

8.
At the European level there is an increasing focus on how freight transport can be moved from trucks on roads to more environmentally friendly modes such as rail and ship. A large proportion of the transport services between OD pairs, however, cannot be substituted since there is only one alternative available. The paper investigates the magnitude of this “structural inelasticity” of modal substitution in freight transport due to a sparser layout of rail and ship-based freight networks compared to road. In the analysis we use a recent Scandinavian freight demand model covering more than 800 zones. We find that the structural inelasticity is very significant - in particular for transportation over less than 500 km. Moreover, the inelasticity varies greatly with commodity groups and between OD pairs, and it depends strongly on the port and rail infrastructure. The results suggest that pure charging instruments (road pricing for trucks) in many regions will have limited mode substitution impacts. However, if combined with structural changes in terms of improved infrastructure for rail and ship, impacts may be greater.  相似文献   

9.
This paper investigates hub carriers’ airlines-within-airlines (AinA) strategies, intended to establish low-cost divisions offering nonstop flights on rim routes. An initial hub-spoke network is optimal if passenger differentiation between one-stop and nonstop services and via-hub time cost are small. If differentiation is substantial, a mixed one-stop and nonstop (point-to-point) network under AinA is optimal when via-hub time cost is small (large). Low-cost rivals on rim routes weaken AinA adoption and enhance welfare from a monopoly mixed network. In a perfect-substitute case, hub carriers may have excessive incentive to adopt AinA from a welfare viewpoint, especially, when low-cost rivals exist.  相似文献   

10.
Inland navigation plays an important role in the hinterland access of the port of Antwerp. In this paper alternative bundling strategies for container barge transport in the port of Antwerp are analyzed. Four alternative hub scenarios are simulated and compared with the current situation with respect to the operational characteristics of the network. Discrete event simulation is used to analyze the impact on waiting times and capacity utilization at potential hubs and at sea terminals. The hub scenarios under investigation are the organization of an intermodal barge hub on the right river bank, an intermodal hub on the left river bank, a first multihub scenario with a local collection/distribution network and a potentially improved multihub scenario taking into account the specific structure of the port of Antwerp. The second multihub scenario offers most opportunities for reducing the turnaround time of all inland terminals. All hub scenarios lead to important efficiency improvements in the handling of barges at sea terminals.  相似文献   

11.
《Transport Policy》2009,16(1):12-18
The continued growth of interstate freight trucking brings with it the potential for inaccuracies in official government statistics on trucks’ road use and pollutant emission contributions. State government agency emission estimates for states within the US commonly rely on in-state truck and fuel use records. Consequently, these records can incompletely reflect overall truck activity and emissions by neglecting the trucks that are registered and/or are fueled out of state. An in-person interview survey of 433 heavy-duty truck drivers was conducted at select points of entry into California to better understand the contribution of out-of-state trucks, their fuel use, and their emissions in California. The results indicate that non-California-registered trucks and non-California-diesel fuel make up approximately 30% of Class 8 heavy-duty truck mileage on California roads. Non-California-registered-truck mileage is disproportionately concentrated in four California air basins that have significant air quality issues.  相似文献   

12.
In this paper we set up the theoretical framework for the valuation of the Asian-style options traded in the freight derivatives market. Assuming lognormal spot freight dynamics, we show that Forward Freight Agreements (FFA) are also lognormal prior to the settlement period, but that this lognormality subsequently breaks down. We suggest approximate dynamics in the settlement period for the FFA that leads to closed-form option pricing formulas for Asian call and put options written on the spot freight rate indices in the Black [Black, F., 1976. The pricing of commodity contracts. Journal of Financial Economics 3, 167–179] framework. In a Monte Carlo experiment we show that our formula gives very accurate prices, in particular for forward-starting freight options.  相似文献   

13.
In a context of limited organic growth, some low-cost airlines have considered business strategies that are changing two key principles of the low-cost airline business model: fare unbundling and point-to-point operations. Using a multivariate analysis we identify the influence of several route characteristics on the share that European pure low-cost and hybrid low-cost carriers have on the routes they operate. Results show that, from a network perspective, the distance between the archetypical low-cost carrier business model and the adapted low-cost carrier business model with a hybrid approach is widening. Differences are also clear between hybrids offering connecting services and hybrids offering fare bundling. The results are also important from an airport policy perspective, since secondary airports and legacy airports in transition could be able to reduce the gap between them and the main hub airports.  相似文献   

14.
贾磊 《铁道运输与经济》2021,(2):110-117,130
合理确定兰州铁路枢纽布局有助于完善西北地区铁路网络,促进兰州—西宁城市群发展,提升欧亚大陆桥互联互通能力,发挥兰州地区的桥头堡作用。阐述兰州铁路枢纽现状,指出枢纽内客运站分工及货运设施功能存在问题,提出枢纽发展规划;研究提出兰州铁路枢纽总图方案,包括干支线、疏解线及联络线工程方案与总图方案设计。研究结果表明,兰州将形成衔接11条铁路干线,南客北货的大型环状枢纽格局,更好地支撑西北地区核心路网运输。  相似文献   

15.
The single pricing approach fails to reflect different demand changes in response to its cargo space prices at different sales periods. This might be an obstacle to maximize the cargo space revenue of air freight carriers. This paper conducts the empirical analysis on pricing strategies in the spot market for two competitive air freight transport carriers operating on the same segment. It concludes that two carriers gain more revenues with the optimized differential pricing approach than with the single pricing approach. In theory, the research enriches the current literature in terms of pricing strategy optimization under the competition of two parties. In practice, it provides references for air freight transport carriers in their decision-making of applying the differential pricing strategy.  相似文献   

16.
We consider the carrier’s optimal bid generation problem in combinatorial auctions for transportation procurement. Bidders (carriers) employ vehicle routing models to identify sets of lanes (origin-destination pairs) based on the actual routes that a fleet of trucks will follow in order to maximize profit. Routes are constructed by optimally trading off repositioning costs of vehicles and the rewards associated with servicing lanes. The carrier optimization represents simultaneous generation and selection of routes and can incorporate any existing commitment. We employ both column generation and Lagrangian based techniques for solving the carrier optimization model and present numerical results.  相似文献   

17.
In this paper, we present an air transport connectivity model for air freight. For the purposes of this paper, connectivity is defined as all possible direct and indirect connections to or from an airport operated by wide-body aircraft, weighted for the quality of the connection in terms of transhipment and in-flight times. Using this model, we analyse the networks of seven European airports. Europe’s largest hub airports carry most air freight thanks to their extensive intercontinental passenger networks, while smaller airports with a strong focus on air freight carry large amounts of cargo on dedicated freighter aircraft. For air freight operations, the catchment area of an airport is much larger than it is for passenger services, as shipments are being trucked to their departure airport throughout all of mainland Europe. Since there are many airports sharing the same catchment area, potential competition for air freight is fierce. We found that well located regions between the four large European airports have access to large air freight networks, whilst regional air freight connectivity in northern and southern parts of Europe is substantially lower.  相似文献   

18.
This research addresses strategic planning for an interregional, hub based, intermodal logistics network operated by a logistics service provider. A tabu search meta-heuristic is used to solve a mathematical optimization model that extends the p-hub median model for interacting hub location-allocation problems to the domain of intermodal logistics. An empirical study based on a subset of US freight flows shows that intermodal logistics networks differ significantly from traditional over-the-road logistics networks in their hub locations, network structure, and their use of direct and inter-hub shipments. Furthermore, intermodal logistics networks are more sensitive to changes in service requirements and costs.  相似文献   

19.
This paper presents one of the first models explaining the choice of time-period in road freight transport. Policies that would shift some fraction of the trucks from peak to earlier and later periods will contribute to the reduction of congestion. Therefore there is an increasing interest in modelling the time-period sensitivity of road freight transport to changes in travel time and cost by period. The model developed here is based on a stated preference survey amongst receivers of goods in Flanders and was implemented in the strategic freight transport model of the Flemish authorities.  相似文献   

20.
A bi-level modelling approach is proposed to represent the interaction between the vehicle loading practices of road freight transport carriers, and the decisions of a road planning authority responsible both for road maintenance and for the enforcement of overloading control. At the lower (reactive) level, the overloading decisions of the carriers impact on road maintenance expenditure, while at the upper (anticipatory) level the planner decides fine and enforcement levels by anticipating the responses of the carriers. A case study using data from Mexico is used to illustrate the method.  相似文献   

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