Airline network choice and market coverage under high-speed rail competition

While the existing literature has focused on the short-term impacts, this paper investigates the long-term impacts of high-speed rail (HSR) competition on airlines. An analytical model is developed to study how an airline may change its network and market coverage when facing HSR competition on trunk routes. We show that prior to HSR competition, an airline is more likely to adopt a fully-connected network and cover fewer fringe markets if the trunk market is large. Under HSR competition, the airline will, for a given network structure, have a greater incentive to cover more fringe (regional or foreign) markets if the trunk market is large, or the airline network is close to hub-and-spoke. Further, the airline will, for any given market coverage, move towards a hub-and-spoke network when the trunk market is large, or the number of fringe markets covered by the airline network is large. Both effects are more prominent when the decreasing rate of airline density economies is large. We further show that HSR competition can induce the airline to adopt network structure and market coverage that are closer to the socially optimal ones, thereby suggesting a new source of welfare gain from HSR based on its long-term impacts on airlines. Implications for operators, policy makers and specific countries (such as China) are also discussed.     

Global optimization method for mixed transportation network design problem: A mixed-integer linear programming approach

This paper proposes a global optimization algorithm for solving a mixed (continuous/discrete) transportation network design problem (MNDP), which is generally expressed as a mathematical programming with equilibrium constraint (MPEC). The upper level of the MNDP aims to optimize the network performance via both expansion of existing links and addition of new candidate links, whereas the lower level is a traditional Wardrop user equilibrium (UE) problem. In this paper, we first formulate the UE condition as a variational inequality (VI) problem, which is defined from a finite number of extreme points of a link-flow feasible region. The MNDP is approximated as a piecewise-linear programming (P-LP) problem, which is then transformed into a mixed-integer linear programming (MILP) problem. A global optimization algorithm based on a cutting constraint method is developed for solving the MILP problem. Numerical examples are given to demonstrate the efficiency of the proposed method and to compare the results with alternative algorithms reported in the literature.     

养护施工总承包模式下业主与承包商的博弈分析

文章以博弈论为理论基础,分析了养护施工总承包模式下业主与总承包商的博弈关系,提出了引导双方采用合理的策略以获得最大利益及保证工程产品达到较高质量水平的博弈对策,为养护施工总承包工程的管理和施工提供方法借鉴。     

Variations in household transport expenditure within major Australian cities

A comparative analysis of intra‐urban variations in household transport expenditure in 1966–68 is undertaken for the two largest Australian cities, Sydney and Melbourne, and one of the smaller State capitals, Adelaide. Regional variations in transport expenditure are found to be greater the larger the city; however residents of small cities are more dependent upon the car for their motorised travel. In the larger cities car dependence is most evident among low‐to‐middle income groups at a relatively early stage in the life cycle, located in outer suburban areas. Consequently high levels of expenditure on transport typically coincide with relatively high levels of financial commitments to home purchase and/or operation. This has significant ramifications for the household budget, the most notable being deficit‐funding, and reduced outlays on other expenditure items such as recreation and education. The distribution of company vehicles and allowances is shown to be of relatively greater benefit to higher income groups, although is not confined to them. Although somewhat dated, the findings suggest that the social impacts of rising prices for energy will almost certainly be regressive.

Note: This paper was presented to the 7th PTRC Summer Annual Meeting held at the University of Warwick in July 1979. The authors gratefully acknowledge the contribution of the Australian Road Research Board in the preparation of the paper. Particular appreciation is expressed to Dr. M. R. Wigan, Mr. K. Sharp and Dr. M. G. Lay for their helpful comments.     

天然气管网的初始流量分配

在对天然气管网进行离线数值模拟计算时,需要给各管段分配初始流量,作为迭代计算的初始值。根据管道的流动状态多在阻力平方区的特点,建立初始流量分配的数学模型,用C 语言编制出计算程序。对实例进行计算和分析,表明用最小平方和法求解各管段初始流量时,不需手工预分初始流量,也不需预先确定各管段流体流动方向,求解所得初始值接近真实值,使数值计算的收敛速度大大提高。     

Does an increase in subsidies lead to changes in air fares? Empirical evidence from Spain

This paper examines the impact on prices of various regulatory changes in residents’ flight subsidies implemented in Spain in recent years. It draws on a large sample of domestic routes for the period 2003–2013 to estimate a price equation that accounts for the panel data and the potential endogeneity of specific explanatory variables. Price differences were not found between the treated routes (routes affected by the discounts) and the control routes (routes not affected by the discounts). This is the case regardless of the discount percentage on prices that island residents enjoy.     

Future electricity demand from battery‐powered vehicles

An important decision faced by airline schedulers is how to adapt the flight schedule and aircraft assignment to unforeseen perturbations in an established schedule. In the face of unforeseen aircraft delays, schedulers have to decide which flights to delay, and when delays become excessive, which to cancel. Current scheduling models deal with simple decision problems of delay or cancellation, but not with both simultaneously. But in practice the optimal decision may involve results from the integration of both flight cancellations and delays. In Part I of this paper, a quadratic programming model for the integration decision problem is given. The model can formulate the integration of flight cancellations and delays as well as some special cases, such as the ferrying of surplus aircraft and the possibility of swapping different types of aircraft. In this paper, based on the special structure of the model, an effective algorithm is presented, sufficient computational experiments are conducted and some results are reported. These show that we can expect to obtain a sufficiently good solution in terms of reasonable CPU time.     

Active or passive? Sustainable manufacturing in the direct-channel green supply chain: A perspective of two types of green product designs

This paper considers a supply chain in which a manufacturer produces and sells two types of green products in its direct channel under government interventions aiming to improve social welfare. There is a Stackelberg game between the two stakeholders. Our research derives the closed form solutions to the optimal tax, green degree and price for the products, and obtains the strategies for government and manufacturer under different environmental policies. By considering six scenarios, our models obtain the best choice from the comparison between the two cases in which the manufacturer determines its product green degree actively or accepts the green standard set by the government passively. Then, we conduct some sensitivity analyses and explore the scenario in which there is competition between green products and non-green products. The results of this research indicate that the government setting the product green standard and providing the manufacturer with a subsidy is significant.     

Exploring airline passengers’ willingness to pay for carbon offsets

This study examines airline passengers’ willingness to pay for carbon-offsets. Using the contingent valuation method of double-bounded dichotomous choice format and a survey of over 1000 Taiwanese passengers flying to countries in Asia, Europe, North America, and Oceania to gauge their willingness-to-pay for airline carbon-offsets. The results suggest that despite the trip characteristics and personal background, air travel passengers’ knowledge and perceptions of the carbon-offset scheme also greatly influence the stated willingness to pay.     

British location rents: an interpretation of the dual transportation problem for commodity flows

The transportation problem is solved for a number of commodity flow matrices for Britain for 1972. The commodities were selected because of the likelihood of the transportation problem producing a relatively good fit. Commodities were also chosen when it was thought that accessibility was a key location factor. The rationalisation of the interpretation of the dual values as shadow prices and location rents is outlined and, after discussing the merits of alternative means of analysing and presenting the dual values, the distribution of these values are compared with the actual location of industry. Some difficulties and further implications of the approach are suggested.     

Policy analysis of third party electronic coupons for public transit fares

Mobile technologies are generating new business models for urban transport systems, as is evident from recent startups cropping up from the private sector. Public transport systems can make more use of mobile technologies than just for measuring system performance, improving boarding times, or for analyzing travel patterns. A new transaction model is proposed for public transport systems where travelers are allowed to pre-book their fares and trade that demand information to private firms. In this public-private partnership model, fare revenue management is outsourced to third party private firms such as big box retail or large planned events (such as sports stadiums and theme parks), who can issue electronic coupons to travelers to subsidize their fares. This e-coupon pricing model is analyzed using marginal cost theory for the transit service and shown to be quite effective for monopolistic coupon rights, particularly for demand responsive transit systems that feature high cost fares, non-commute travel purposes, and a closed access system with existing pre-booking requirements. However, oligopolistic scenarios analyzed using game theory and network economics suggest that public transport agencies need to take extreme care in planning and implementing such a policy. Otherwise, they risk pushing an equivalent tax on private firms or disrupting the urban economy and real estate values while increasing ridership.     

Airline energy efficiency measures using the Virtual Frontier Network RAM with weak disposability

In this paper, airline energy efficiency is divided into three stages: the operations stage, the services stage and the sales stage. Greenhouse gas emissions are treated as an undesirable output of the services stage. This new three-stage strategic operating framework is a modification of existing models. A new model, Virtual Frontier Network Range Adjusted Measure with weak disposability, is proposed to evaluate the efficiencies of 22 international airlines, from 2008 to 2012. The results show that the new model can establish more reasonable rankings and confirm new benchmarking airlines and that inclusion in the European Union’s Emissions Trading Scheme has had little influence on the improvement of airline energy efficiency.     

基于改进Dijkstra算法的路径优化仿真研究

文章针对传统Dijkstra算法在路径优化过程中存在的不足,从路网拓扑关系存储和快速搜索技术两方面对其进行了改进,得到了一种改进的Dijkstra算法,并通过实例仿真分析,验证了该算法的有效性。