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691.
Scrutinizing individuals’ leisure-shopping travel decisions to appraise activity-based models of travel demand 总被引:1,自引:0,他引:1
Diana Kusumastuti Els Hannes Davy Janssens Geert Wets Benedict G. C. Dellaert 《Transportation》2010,37(4):647-661
Activity-based models for modeling individuals’ travel demand have come to a new era in addressing individuals’ and households’
travel behavior on a disaggregate level. Quantitative data are mainly used in this domain to enable a realistic representation
of individual choices and a true assessment of the impact of different Travel Demand Management measures. However, qualitative
approaches in data collection are believed to be able to capture aspects of individuals’ travel behavior that cannot be obtained
using quantitative studies, such as detailed decision making process information. Therefore, qualitative methods may deepen
the insight into human’s travel behavior from an agent-based perspective. This paper reports on the application of a qualitative
semi-structured interview method, namely the Causal Network Elicitation Technique (CNET), for eliciting individuals’ thoughts
regarding fun-shopping related travel decisions, i.e. timing, shopping location and transport mode choices. The CNET protocol
encourages participants to think aloud about their considerations when making decisions. These different elicited aspects
are linked with causal relationships and thus, individuals’ mental representations of the task at hand are recorded. This
protocol is tested in the city centre of Hasselt in Belgium, using 26 young adults as respondents. Response data are used
to apply the Association Rules, a fairly common technique in machine learning. Results highlight different interrelated contexts,
instruments and values considered when planning a trip. These findings can give feedback to current AB models to raise their
behavioral realism and to improve modeling accuracy. 相似文献
692.
This work presents a methodology to evaluate the level of service (LOS) of an airport baggage claim. A psychometric scaling technique is employed to obtain quantitative data from qualitative data (user responses as a function of five rating categories). Regression analysis is applied to obtain a statistically valid relationship between user responses and observed operational indicators. The proposed model is developed from a case study of the West Jet baggage claim area at the Calgary International Airport – Canada, where 62 passengers have been observed and interviewed. The collected data allowed the proposal of standards, which indicate tolerable limits as a function of various LOS ranges (A–E). The results are useful for managers and designers on assessing the LOS offered in a terminal, but also during the planning and design stages of an airport. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
693.
694.
Hoyte C. Raven 《Journal of Marine Science and Technology》2010,15(4):331-344
This paper discusses a rational and systematic procedure for understanding and analysing steady ship wave patterns and their
dependence on hull form. A stepwise procedure is proposed in which the pressure distribution around the hull is invoked to
provide a qualitative understanding of the connection between hull form and wave making. In a recent publication it was shown
how this understanding explains various known trends and, in combination with wave pattern computations by free-surface potential
flow or Reynolds-averaged Navier–Stokes (RANS) methods, can often be exploited to reduce wave making by modifying the hull
form. The present paper provides support for the guidelines given, validates the decomposition into different steps and indicates
the connection with previous theoretical approaches. 相似文献
695.
This paper introduces a new method for the prediction of ship maneuvering capabilities. The new method is added to a nonlinear
six-degrees-of-freedom ship motion model named the digital, self-consistent ship experimental laboratory (DiSSEL). Based on
the first principles of physics, when the ship is steered, the additional surge and sway forces and the yaw moment from the
deflected rudder are computed. The rudder forces and moments are computed using rudder parameters such as the rudder area
and the local flow velocity at the rudder, which includes contributions from the ship velocity and the propeller slipstream.
The rudder forces and moments are added to the forces and moments on the hull, which are used to predict the motion of the
ship in DiSSEL. The resulting motions of the ship influence the inflow into the rudder and thereby influence the force and
moment on the rudder at each time step. The roll moment and resulting heel angle on the ship as it maneuvers are also predicted.
Calm water turning circle predictions are presented and correlated with model test data for NSWCCD model 5514, a pre-contract
DDG-51 hull form. Good correlations are shown for both the turning circle track and the heel angle of the model during the
turn. The prediction for a ship maneuvering in incident waves will be presented in Part 2. DiSSEL can be applied for any arbitrary
hull geometry. No empirical parameterization is used, except for the influence of the propeller slipstream on the rudder,
which is included using a flow acceleration factor. 相似文献
696.
The environment onboard a ship presents a typical example of a severe environment, displaying extreme conditions of temperature
and relative humidity, especially in the engine room. Datasheets, the international labour organization, and standards do
not provide clear information about the suitable ambience of the engine room, its design conditions, and the role of marine
engineers in preventing work-related risk. In this study, air temperature and relative humidity were monitored at several
locations onboard a merchant ship. These real monitored data were then compared with the ISO design indications to obtain
an effective work risk analysis. From these indoor temperature and relative humidity data, the corresponding parameters of
thermal comfort in the engine control room and the heat stress and sweating index of a worker in the engine room were determined.
As a function of these indices, the maximum time that a worker can stay in the engine room and the time for which he must
rest in the control room were also calculated in the present study. Some design corrections are also proposed herein to improve
these environments. 相似文献
697.
Airline alliances are a global transportation issue which is the subject of increasing attention in the literature. A simple simulation model of air carrier competition in a network is constructed to examine the economic welfare effects of different levels of alliance between the carriers serving the network. The simulations confirm that consumers derive benefits from improved access to passenger markets. However, in many cases, carriers tend to gain from a limited alliance such as code-sharing. This suggests that closer alliances may be driven by other considerations such as raising barriers to entry or the cross-subsidisation of international routes through greater control of the domestic market. 相似文献
698.
For the restricted construction site of a Beijing metro station surrounded by many important buildings and characterized by complex staggered underground pipelines, many construction difficulties and a high level of re-quired management, settlement monitoring is necessary for the sake of construction safety. A 3D model of the metro,a model of the specially shaped structure and models of many details of the metro were established using the BIM technique, allowing for: creation of a 3D presentation, extraction of construction quantities, construction conse-quence optimization, guidance of construction endeavors, simulation of the construction process, 4D dynamic con-struction management and 4D dynamic settlement monitoring. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
699.
700.
The wide adoption of location-enabled devices, together with the acceptance of services that leverage (personal) data as payment, allows scientists to push through some of the previous barriers imposed by data insufficiency, ethics and privacy skepticism. The research problems whose study require hard-to-obtain data (e.g. transportation mode detection, service contextualisation, etc.) have now become more accessible to scientists because of the availability of data collecting outlets. One such problem is the detection of a user's transportation mode. Different fields have approached the problem of transportation mode detection with different aims: Location-Based Services (LBS) is a field that focuses on understanding the transportation mode in real-time, Transportation Science is a field that focuses on measuring the daily travel patterns of individuals or groups of individuals, and Human Geography is a field that focuses on enriching a trajectory by adding domain-specific semantics. While different fields providing solutions to the same problem could be viewed as a positive outcome, it is difficult to compare these solutions because the reported performance indicators depend on the type of approach and its aim (e.g. the real-time availability of LBS requires the performance to be computed on each classified location). The contributions of this paper are three fold. First, the paper reviews the critical aspects desired by each research field when providing solutions to the transportation mode detection problem. Second, it proposes three dimensions that separate three branches of science based on their main interest. Finally, it identifies important gaps in research and future directions, that is, proposing: widely accepted error measures meaningful for all disciplines, methods robust to new data sets and a benchmark data set for performance validation. 相似文献