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991.
Yung-Hsiang Cheng 《Transportation》2010,37(6):875-896
Although people are often encouraged to use public transportation, the riding experience is not always comfortable. This study
uses service items to measure passenger anxieties by applying a conceptual model based on the railway passenger service chain
perspective. Passenger anxieties associated with train travel are measured using a modern psychometric method, the Rasch model.
This study surveys 412 train passengers. Analytical results indicate that the following service items cause passenger anxiety
during trains travel: crowding, delays, accessibility to a railway station, searching for the right train on a platform, and
transferring trains. Empirical results obtained using the Rasch approach can be used to derive an effective strategy to reduce
train passenger anxiety. This empirical study also demonstrates that anxiety differs based on passenger sex, age, riding frequency,
and trip type. This information will also prove useful for transportation planners and policy-makers when considering the
special travel needs of certain groups to create a user-friendly railway travel environment that promotes public use. 相似文献
992.
This paper proposes a new activity-based transit assignment model for investigating the scheduling (or timetabling) problem
of transit services in multi-modal transit networks. The proposed model can be used to generate the short-term and long-term
timetables of multimodal transit lines for transit operations and service planning purposes. The interaction between transit
timetables and passenger activity-travel scheduling behaviors is captured by the proposed model, as the activity and travel
choices of transit passengers are considered explicitly in terms of departure time choice, activity/trip chain choices, activity
duration choice, transit line and mode choices. A heuristic solution algorithm which combines the Hooke–Jeeves method and
an iterative supply–demand equilibrium approach is developed to solve the proposed model. Two numerical examples are presented
to illustrate the differences between the activity-based approach and the traditional trip-based method, together with comparison
on the effects of optimal timetables with even and uneven headways. It is shown that the passenger travel scheduling pattern
derived from the activity-based approach is significantly different from that obtained by the trip-based method, and that
a demand-sensitive (with uneven headway) timetable is more efficient than an even-headway timetable. 相似文献
993.
Mass transit projects are often a top contender of many cities to meet their increasing demand for travel. Despite the global
trend of privatization, mass transit services, as public goods, remain largely being provided and operated by the public sector.
Hong Kong is one of the few exceptions that all mass transit services are commercially operated. Both rail and bus services
in Hong Kong are reputable for their quality and profitability, often serving as benchmarks for new projects. In this study,
we investigate the factors contributing to this success. In particular, we ascertain the quality of transit service provision
by the private sector over the past two decades. Then, we conduct an in-depth analysis of the account books of leading railway
and bus operators in Hong Kong so as to shed light on their financial viability. Through this study, we hope to present crucial
factors for providing financially viable private transit services. 相似文献
994.
This paper deals with the lane assignment problem in the Automated Highway Systems (AHS). The purpose of lane assignment strategies
is to increase throughput on multi-lane highways with many entry and exit points, based on the itineraries of vehicles using
the highway (point of entry, time of entry and exit point) and the effects of maneuvers. Using partitioned lane assignment
strategies, the lane assignment problem is formulated as an optimization problem to find the proper positions of partitions.
Then the optimal problem is solved using a Genetic Algorithm (GA). The proposed algorithm has been validated by comparing
its solution with that of an all-cases algorithm for a simple case. Moreover, a traffic simulator with a realistic car-following
model as well as lane change logic has been developed. The simulation results show the efficiency of the proposed genetic
algorithm, compared with random assignment algorithms. 相似文献
995.
This paper seeks to explore the relationship between mode and destination choice in an integrated nested choice model. A fundamental
argument can be made that in certain circumstances, the ordering of choices should be reversed from the usual sequence of
destination choice preceding mode choice. This results in a travel demand model where travelers are more likely to change
destinations than to change transportation modes. For small and medium size urban areas, particularly in the United States,
with less well developed public transit systems that draw few choice riders, this assumption makes much more sense than the
traditional modeling assumptions. The models used in the new travel modeling system developed for Knoxville, Tennessee utilize
this reversed ordering, with generally good results, which required no external tinkering in the logsum parameters. 相似文献
996.
The paper reports a modelling system to simulate goods movements at an urban scale. It allows joint analysis of choices made
by end-consumers (assumed to be families) and retailers. These movements are examined at two levels: analysis of commodity
flows, in terms of quantity, generated by the consumption of commodities; analysis of commodity flows, in terms of vehicles,
due to restocking. The first level allows us to calculate the goods quantity flows due to consumption and restocking; the
second level allows us to determine the service, vehicles used and target time, as well as the route chosen for restocking
sales outlets in order to estimate vehicle flows on the urban/metropolitan transportation network. The modelling system is
a multi-step model and considers a disaggregated approach for each decisional level. 相似文献
997.
In the quest for sustainable travel, short distances appear the most amenable to curbing the use of the automobile. Existing studies about short trips evaluate the potential of shifting from the automobile to sustainable travel options while considering the population as homogeneous in its preferences and its tendency to accept these alternative travel options as realistic. However, this assumption appears quite unrealistic and the current study offers a different perspective: the mode choices when travelling short distances are likely related to lifestyle decisions. Short trip chains of a representative sample of the Danish population in the Copenhagen Region were analysed, and more specifically a latent class choice model was estimated to uncover latent lifestyle groups and choice specific travel behaviour. Results show that four lifestyle groups are identified in the population: car oriented, bicycle oriented, public transport oriented and public transport averse. Each lifestyle group has specific perceptions of travel time (with extremely different rates of substitution between alternative travel modes), transfer penalties in public transport trip chains, weather influence (especially on active travel modes), and trip purpose effect on mode selection. Consequently, when thinking about measures to increase the appeal of sustainable travel options, decision-makers should look at specific individuals within the population and more sensitive individuals to comfort and level-of-service improvements across the lifestyle groups. 相似文献
998.
The relationship between financial system, law framework or economic growth has attracted considerable attention for years. However, there are some questions still remaining unanswered: between tangible assets protection and intellectual property protection, which is more important? Between external financing and property rights protection, which does play a greater role for the economic development? According to the dynamic stochastic general equilibrium(DSGE) model with non-free market factors, we study the effectiveness of property protection and external financing, and try to answer these questions. The model fits the data well, and we find:(1) protection of intellectual property plays a more important role than that of tangible asset, in the promotion of economy;(2) relaxation of financial constraints on corporate is more effective in the short run, while the protection of intellectual property is more effectual in the long term. 相似文献
999.
An assessment of the rationale for the vertical disintegration of ship management suggests that there might be compelling economic benefits for the separation of ownership from management. In this context, as a means for developing effective marketing strategies, it is important for ship managers to know the criteria used by current and prospective clients for ship manager selection and evaluation. The aim of this paper is to empirically identify the dimensions for ship manager selection and performance evaluation and their relative importance and to discuss the implications for marketing emanating from such an assessment. The methodology adopted includes the collection of secondary and primary data, both from ship managers and their clients, using interviews and a mail survey. The results indicate the prevailing importance of certain dimensions in selection (e.g. technical ability, reputation, competency) and evaluation (responsiveness, trustworthiness, technical ability), whereas it also found that price alone is not perceived to be as important in ship manager selection. It is concluded that placing emphasis on such dimensions in the formulation of a marketing strategy will contribute towards the attraction and retention of clients, whereas cost-cutting measures to allow price reduction, as well as advertising, will be ineffective over the long term. 相似文献
1000.