Research Output

@article{Feng2014c,

title = {Multicriteria evaluation on accessibility-based transportation equity in road network design problem},

author = {T. Feng and J. Zhang},

doi = {10.1002/atr.1202},

issn = {20423195},

year  = {2014},

date = {2014-01-01},

journal = {Journal of Advanced Transportation},

volume = {48},

issue = {6},

abstract = {This paper investigates the performance of accessibility-based equity measurements in transportation and proposes a multiobjective optimization model to simulate the trade-offs between equity maximization and cost minimization of network construction. The equity is defined as the spatial distribution of accessibilities across zone areas. Six representative indicators were formulated, including GINI coefficient, Theil index, mean log deviation, relative mean deviation, coefficient of variation, and Atkinson index, and incorporated into an equity maximization model to evaluate the performance sensitivity. A bilevel multiobjective optimization model was proposed to obtain the Pareto-optimal solutions for link capacity enhancement in a stochastic road network design problem. A numerical analysis using the Sioux Falls data was implemented. Results verified that the equity indicators are quite sensitive to the pattern of network scenarios in the sense that the level of equity varies according to the amount of overall capacity enhancement as well as the assignment of improved link segments. The suggested multiobjective model that enables representing the Pareto-optimal solutions can provide multiple options in the decision making of road network design.},

keywords = {accessibility, bilevel programming, equity, multiobjective optimization, network design problem},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2014d,

title = {Trade-offs between mobility and equity maximization under environmental capacity constraints: A case study of an integrated multi-objective model},

author = {T. Feng and H. J. P. Timmermans},

doi = {10.1016/j.trc.2014.03.012},

issn = {0968090X},

year  = {2014},

date = {2014-01-01},

journal = {Transportation Research Part C: Emerging Technologies},

volume = {43},

abstract = {This paper investigates the performance of a policy decision tool proposed for multi-objective decision under different policy interventions. This tool deals with the trade-off between mobility and equity maximization under environmental capacity constraints. Two system objectives, maximization of mobility and equity, are formulated in terms of the sum of total car ownership and number of trips, and the differences in accessibility between zones. Environmental capacities are based on production efficiency theory in which the frontier emission under maximum system efficiency is taken as environmental capacity. To examine the performance of the proposed model, three types of hypothetical policies (network improvement, population increase and urban sprawl) are formulated. Effects are simulated using data pertaining to Dalian City, China. Results show that the proposed model is capable of representing the trade-offs between mobility and equity based on different policy interventions. Compared with two extreme cases with the single objective of mobility maximization or equity maximization, the Pareto-optimal solutions provide more interesting practical options for decision makers. Taking the solution based on the maximum equity as an example, the policy of urban sprawl yields the most significant improvement in both emission and accessibility of the three scenarios. © 2014 Elsevier Ltd.},

keywords = {Accessibility-based equity, Car ownership, Environmental capacity, Mobility, Policy decision making},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2014e,

title = {Superimposing activity–travel sequence conditions on GPS data imputation},

author = {Tao Feng and Harry J. p. Timmermans},

doi = {10.1080/17489725.2014.977361},

issn = {1748-9725},

year  = {2014},

date = {2014-01-01},

journal = {Journal of Location Based Services},

volume = {8},

issue = {4},

pages = {256-267},

publisher = {Taylor and Francis Ltd.},

abstract = {Applications of new technology in travel surveys have demonstrated the possibility to obtain good quality activity data than traditional survey methods. However, the quality of the imputation diary data highly depends on the predictability of data processing algorithms, which are not fully ready yet. Narrowing the gap between imputation results and true activity–travel patterns is necessary to improve the ease of data confirmation in prompted recall surveys and develop fully automatic data imputation systems. This paper proposes an algorithm to decrease the discrepancies between imputed activity–travel diary and the so-called ground truth. Based on the activity–travel pattern obtained using a Bayesian belief network model, the algorithm takes into account the consistency of the full activity–travel pattern within a day in the sense that the activity–travel sequence is represented in terms of a hierarchical set of tours, and the transportation modes within a tour are logically consistent. We explore three different approaches based on the frequency at the trip/tour level and imputation probability at the epoch level, for each transportation mode. Results obtained based on the test using GPS data in the Netherlands show that the new algorithm significantly improves the imputation accuracy of transportation modes compared with an algorithm that does superimpose these pattern constraints.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2014f,

title = {Extracting activity-travel diaries from GPS data: towards integrated semi-automatic imputation},

author = {Tao Feng and Harry J. p. Timmermans},

doi = {10.1016/j.proenv.2014.11.018},

issn = {1878-0296},

year  = {2014},

date = {2014-01-01},

journal = {Procedia Environmental Sciences},

volume = {22},

pages = {178-185},

note = {12th International Conference on Design & Decision Support Systems in Architecture and Urban Planning (DDSS 2014)<br/>, DDSS 2014 ; Conference date: 25-08-2014 Through 27-08-2014},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2013,

title = {Capturing preference heterogeneity of truck drivers' route choice behavior with context effects using a latent class model},

author = {T. Feng and T. Arentze and H. Timmermans},

doi = {10.18757/ejtir.2013.13.4.3004},

issn = {15677141},

year  = {2013},

date = {2013-01-01},

journal = {European Journal of Transport and Infrastructure Research},

volume = {13},

issue = {4},

abstract = {This paper investigates heterogeneity in truck drivers' route choice preferences. A latent class model is estimated to identify heterogeneous segments of drivers. A stated choice experiment designed for identifying route choice behavior of truck drivers provides the data for model estimation. The effects of road pricing and environmental bonus are examined considering context dependency. Results reveal that size of truck is a significant segmentation variable of preferences for route attributes. Drivers of light trucks care more about congestion than drivers of heavy trucks, and are highly sensitive to road pricing and slightly sensitive to a road bonus. Drivers of heavy trucks are more sensitive to road category and urban area than drivers of light trucks, and are insensitive to bonus and slightly sensitive to pricing.},

keywords = {Context effects, Freight transport, Heterogeneity, Latent class model, Route choice behavior},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2013b,

title = {Transportation mode recognition using GPS and accelerometer data},

author = {T. Feng and H. J. P. Timmermans},

doi = {10.1016/j.trc.2013.09.014},

issn = {0968090X},

year  = {2013},

date = {2013-01-01},

journal = {Transportation Research Part C: Emerging Technologies},

volume = {37},

abstract = {Potential advantages of global positioning systems (GPS) in collecting travel behavior data have been discussed in several publications and evidenced in many recent studies. Most applications depend on GPS information only. However, transportation mode detection that relies only on GPS information may be erroneous due to variance in device performance and settings, and the environment in which measurements are made. Accelerometers, being used mainly for identifying peoples' physical activities, may offer new opportunities as these devices record data independent of exterior contexts. The purpose of this paper is therefore to examine the merits of employing accelerometer data in combination with GPS data in transportation mode identification. Three approaches (GPS data only, accelerometer data only and a combination of both accelerometer and GPS data) are examined. A Bayesian Belief Network model is used to infer transportation modes and activity episodes simultaneously. Results show that the use of accelerometer data can make a substantial contribution to successful imputation of transportation mode. The accelerometer only approach outperforms the GPS only approach in terms of the predictive accuracy. The approach which combines GPS and accelerometer data yields the best performance. © 2013 Elsevier Ltd.},

keywords = {Accelerometer, Activity type, Bayesian belief network, GPS, Transportation mode},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2013e,

title = {Map matching of GPS data with bayesian belief networks},

author = {T Feng and H J P Timmermans},

issn = {1881-1124},

year  = {2013},

date = {2013-01-01},

journal = {Journal of the Eastern Asia Society for Transportation Studies},

volume = {10},

pages = {100-112},

abstract = {This paper proposes a map matching algorithm using Bayesian belief network for GPS traces to generate the spatial-temporal information of individuals. The algorithm incorporates the road network topology, distance from trace nodes to road segments, the angle between two lines, direction difference, accuracy of measured GPS log point, and position of roads. The GPS data collected in the Eindhoven region, The Netherlands, was used to examine the performance of this algorithm. Results based on a small sample show that the algorithm has a good performance in both processing efficiency and prediction accuracy of correctly identified instances. Even with a small sample, the overall prediction accuracy reaches 87.02%.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Arentze2012,

title = {Context-dependent influence of road attributes and pricing policies on route choice behavior of truck drivers: Results of a conjoint choice experiment},

author = {T. Arentze and T. Feng and H. Timmermans and J. Robroeks},

doi = {10.1007/s11116-012-9391-z},

issn = {15729435},

year  = {2012},

date = {2012-01-01},

journal = {Transportation},

volume = {39},

issue = {6},

abstract = {In this paper, we report the results of a stated choice experiment, which was conducted to examine truck drivers' route choice behavior. Of particular interest are the questions (i) what is the relative importance of road accessibility considerations via-a-vis traditional factors influencing route choice behavior, (ii) what are the influences of particular personal and situational variables on the evaluation of route attributes, (iii) how sensitive are truck drivers for possible pricing policies, and (iv) is there a difference in impact if environmental concerns are framed as a bonus or as a pricing instrument. The main findings indicate that road accessibility characteristics have a substantial impact on route preferences which is of the same order of magnitude as variation in travel times. This suggests that provision of adequate travel information in itself can be an effective instrument to prevent negative externalities of good transport associated with shortest routes. Furthermore, the results indicate that truck drivers/route planners when choosing a route are relatively sensitive to road pricing schemes and rather insensitive to environmental bonuses. © 2012 The Author(s).},

keywords = {Freight transport, Price policies, Route choice, Stated choice experiment},

pubstate = {published},

tppubtype = {article}

}

@article{Arentze2012b,

title = {Compliance with and influence of a new in-car navigation system for trucks: Results of a field test},

author = {T. Arentze and T. Feng and J. Robroeks and M. Brakel and R. Huibers},

doi = {10.1016/j.tranpol.2012.06.011},

issn = {0967070X},

year  = {2012},

date = {2012-01-01},

journal = {Transport Policy},

volume = {23},

abstract = {The use of in-car navigation systems has rapidly grown over the last years. For freight transport, the emphasis on fastest routes is not always in the interest of the truck driver and causes negative externalities when the routes run through built-up area. This paper reports the results of a field test that was conducted to test a new navigation system for trucks. A sample of 100 truck drivers participated in the experiment where they used the new system first in a tracking mode only and next in a full navigation mode for a period of two and a half months in total. During this period drivers kept a diary where they indicated the times and reasons why they deviated from routes suggested by the system. We analyze the diary data and GPS data logged by the system to investigate compliance with and influence of the new navigation system on route choice. The results suggest that the new navigation system for trucks has significant impacts on routes, the most important of which is a shift from use of smaller roads towards larger roads with beneficial consequences in terms of both efficiency and environment. Deviation from suggested routes occurs relatively frequently and for different reasons by drivers of heavy and lighter trucks. We conclude that development of dedicated navigation systems for trucks would serve the interest of the freight transport sector and quality of environment at the same time and more so when route advice is differentiated between heavy and lighter transport. © 2012 Elsevier Ltd.},

keywords = {Compliance, Freight transport, Route choice, Route guidance},

pubstate = {published},

tppubtype = {article}

}

@article{Arentze2012c,

title = {Context-dependent influence of road attributes and pricing policies on route choice behavior of truck drivers : results of a conjoint choice experiment},

author = {T A Arentze and T Feng and H J P Timmermans and J Robroeks},

doi = {10.1007/s11116-012-9391-z},

issn = {0049-4488},

year  = {2012},

date = {2012-01-01},

journal = {Transportation},

volume = {39},

issue = {6},

pages = {1173-1188},

publisher = {Springer},

abstract = {In this paper, we report the results of a stated choice experiment, which was conducted to examine truck drivers route choice behavior. Of particular interest are the questions (i) what is the relative importance of road accessibility considerations via-a-vis traditional factors influencing route choice behavior, (ii) what are the influences of particular personal and situational variables on the evaluation of route attributes, (iii) how sensitive are truck drivers for possible pricing policies, and (iv) is there a difference in impact if environmental concerns are framed as a bonus or as a pricing instrument. The main findings indicate that road accessibility characteristics have a substantial impact on route preferences which is of the same order of magnitude as variation in travel times. This suggests that provision of adequate travel information in itself can be an effective instrument to prevent negative externalities of good transport associated with shortest routes. Furthermore, the results indicate that truck drivers/route planners when choosing a route are relatively sensitive to road pricing schemes and rather insensitive to environmental bonuses.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2012b,

title = {Spatial environmental analysis on the effects of a new navigation system for freight transport},

author = {T Feng and T A Arentze and H J P Timmermans},

doi = {10.1016/j.sbspro.2012.09.776},

issn = {1877-0428},

year  = {2012},

date = {2012-01-01},

journal = {Procedia : Social and Behavioral Sciences},

volume = {54},

pages = {589-597},

publisher = {Elsevier},

abstract = {Considerable attention has been paid to traffic pollution modeling for commercial vehicles due to their high amount of nitrogen compounds, particulate matter and greenhouse gas emissions. Conventional navigation systems for passenger cars enable the route choice process. However, commercial route guidance systems are not targeted to trucks specifically. Recently, a new navigation system has been designed to match the specific requirements of commercial vehicles. The purpose of this paper is to evaluate the effects of such a navigation system on the spatial environment. The major emissions varied by nitrogen compounds and particulate matters are approximated for hot emissions. Emissions on the fastest route and the suggested route followed by drivers are investigated respectively. Spatial analysis is used to investigate the influence on built-up areas along the routes, and a regression analysis is conducted to specify the effects of the new navigation information on total emissions. It is found that the new navigation system has a significant positive effect on the improvement of traffic emissions. The routes suggested by the new navigation system lead to less impact on the built-up areas than the shortest paths.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2011b,

title = {Instantaneous emission modeling with GPS-based vehicle activity data: results of diesel trucks for one-day trips},

author = {T Feng and T A Arentze and H J P Timmermans},

url = {https://www.jstage.jst.go.jp/article/eastpro/2011/0/2011_0_147/_article},

doi = {https://doi.org/10.11175/eastpro.2011.0.147.0},

issn = {1881-1124},

year  = {2011},

date = {2011-01-01},

urldate = {2011-01-01},

journal = {Journal of the Eastern Asia Society for Transportation Studies},

volume = {9},

pages = {756-771},

abstract = {This paper presents an instantaneous analysis for traffic emissions using GPS-based vehicle activity data. The different driving conditions, including real-time and average speed, short-time stops and long-time stops, acceleration and deceleration, etc., are extracted from GPS data. The hot emission, cold-start emission and idling emission, varied by nitrogen compounds and particulate matter are calculated, respectively, in terms of the driving condition and vehicle characteristics. Results simulated based on a one-day trip activity dataset show that trucks spend most kilometers on national roads, followed by municipal and provincial roads. The number of short-time stops is significantly higher than long-time stops, and the time spent for long-time stops is higher than short-time duration. The hot emission accounts for the largest proportion of emissions, and the idling emission also contribute substantially. Results of sensitivity analyses indicate that pollutions in urban area from freight transport can be significantly decreased by increasing the vehicle classes and guiding the heavy trucks out of the region.},

keywords = {Emission, GPS, Transport environment},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2011c,

title = {Assessing the relative importance of input variables for route choice modeling: a neural network approach},

author = {T Feng and T A Arentze and H J P Timmermans},

url = {https://www.jstage.jst.go.jp/article/easts/9/0/9_0_341/_article},

doi = {https://doi.org/10.11175/easts.9.341},

issn = {1881-1124},

year  = {2011},

date = {2011-01-01},

urldate = {2011-01-01},

journal = {Journal of the Eastern Asia Society for Transportation Studies},

volume = {9},

pages = {341-353},

abstract = {This paper identifies the relative importance of variables influencing route choice using a neural network approach. Variables related to route attributes and choice contexts are simultaneously incorporated into the model, and a weight partition algorithm is employed to calculate the strength of influence on route choice decisions. The network is trained and validated using stated preference data. Simulation results show good predictability (97.4% of accuracy) of the neural network model. The relative importance of input variables indicates that road category, pricing, bonus and passing through an urban area are more important. Among all choice contexts, the size of truck is most important, followed by travel time difference and road length. The relative importance identified by the neural network model is consistent with the results of a multinomial logit model, and provide meaningful references for variable selection and model estimation.},

keywords = {Choice models, Machine learning},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2010b,

title = {An integrated model system and policy evaluation tool for maximizing mobility under environmental capacity constraints: A case study in Dalian City, China},

author = {T. Feng and J. Zhang and A. Fujiwara and H. J. P. Timmermans},

doi = {10.1016/j.trd.2010.03.001},

issn = {13619209},

year  = {2010},

date = {2010-01-01},

journal = {Transportation Research Part D: Transport and Environment},

volume = {15},

issue = {5},

abstract = {This paper presents an integrated model system for mobility maximization based on a quantified specification of environmental capacity, and evaluates policy interaction and effectiveness by simulating a number of policy scenarios. The system is designed to specify the maximum level of car ownership and number of trips by private and public modes subject to an environmental capacity constraint defined as the frontier emission under maximum system efficiency. Four types of hypothetical policies (population change, urban sprawl, land-use pattern and network improvement) are designed and the effects of 13 policy scenarios are simulated using data of Dalian City, China. Results reveal that the integrated model system reacts sensitively to policy interventions. The urban sprawl reflected in a changing residential distribution from central to suburban areas is most instrumental from the perspective of pollution alleviation. If the goal is to simultaneously reduce emissions while accommodating mobility, two combinational policy scenarios outperform all others. © 2010 Elsevier Ltd.},

keywords = {Environmental capacity, Integrated model, Mobility maximization, Policy evaluation},

pubstate = {published},

tppubtype = {article}

}

@article{Anggraini2010,

title = {Modeling households activity participation decisions in a rule-based system of travel demand},

author = {R Anggraini and T A Arentze and H J P Timmermans and T Feng},

url = {https://www.jstage.jst.go.jp/article/easts/8/0/8_0_389/_article},

doi = {https://doi.org/10.11175/easts.8.389},

issn = {1881-1124},

year  = {2010},

date = {2010-01-01},

urldate = {2010-01-01},

journal = {Journal of the Eastern Asia Society for Transportation Studies},

volume = {8},

pages = {389-403},

abstract = {This paper describes an empirical derivation of an activity participation choice model at the household level decisions taking into account the allocated activities and joint activity participation of household heads in discretionary activities. The households that we consider here are two-heads households; each is either a worker or non-worker. Attributes of households, such as, for example the presence of young children, attributes of the work activities and space-time settings are considered as explanatory variables. To deal with this large set of attributes and account for non-linear relationships between the variables, a decision tree induction method – CHAID – is used to derive a decision tree model. We show how the decision tree model can be used as a component in an activity-scheduling model, ALBATROSS, to predict travel demand in an activity-based-micro-simulation system. The model shows a satisfactory performance as indicated by its goodness-of-fit on validation data.},

keywords = {Activity participation, Activity-based model, Travel demand},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2010d,

title = {Incorporating accessibility-based equity into stochastic road network design problem: sensitivity analysis and policy Implications},

author = {T Feng and Junyi Zhang and Akimasa Fujiiwara and H J P Timmermans},

doi = {10.11175/easts.8.997},

issn = {1881-1124},

year  = {2010},

date = {2010-01-01},

journal = {Journal of the Eastern Asia Society for Transportation Studies},

volume = {8},

issue = {2010},

pages = {997 – 1010},

abstract = {This paper aims at examining the sensitivity of an accessibility-based equity measure in the context of the stochastic road network design problem. An equity optimization model system based on the bi-level programming approach is proposed, where the upper level problem addresses equity optimization under road investment constraint and the lower level deals with a user equilibrium model reflecting route choice behavior with varied link capacity improvements. An accessibility-based equity measure is defined in terms of the Gini coefficient. To illustrate the applicability of the model, an empirical study using data collected in Dalian City, China is carried out. Results demonstrate that the accessibility-based equity measure can be applied to measure distributional differences in zonal accessibility. Comparative results also implicate that policy makers may need to trade-off the levels of zonal accessibility and the accessibility distribution.},

keywords = {Accessibility distribution, Road network design, Transportation equity},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2009,

title = {Incorporating accessibility-based equity into stochastic road network design problem: sensitive analyses and policy implications},

author = {T Feng and J Zhang and Akimasa Fujiiwara and H J P Timmermans},

issn = {1881-1124},

year  = {2009},

date = {2009-01-01},

journal = {Journal of the Eastern Asia Society for Transportation Studies},

volume = {8},

pages = {997-1010},

abstract = {This paper aims at examining the sensitivity of an accessibility-based equity measure in the context of the stochastic road network design problem. An equity optimization model system based on the bi-level programming approach is proposed, where the upper level problem addresses equity optimization under road investment constraint and the lower level deals with a user equilibrium model reflecting route choice behavior with varied link capacity improvements. An accessibility-based equity measure is defined in terms of the Gini coefficient. To illustrate the applicability of the model, an empirical study using data collected in Dalian City, China is carried out. Results demonstrate that the accessibility-based equity measure can be applied to measure distributional differences in zonal accessibility. Comparative results also implicate that policy makers may need to trade-off the levels of zonal accessibility and the accessibility distribution.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2008,

title = {An integrated modeling framework for environmentally efficient car ownership and trip balance},

author = {T. Feng and J. Zhang and A. Fujiwara},

doi = {10.1016/S0386-1112(14)60212-0},

issn = {03861112},

year  = {2008},

date = {2008-01-01},

journal = {IATSS Research},

volume = {32},

issue = {2},

abstract = {Urban transport emissions generated by automobile trips are greatly responsible for atmospheric pollution in both developed and developing countries. To match the long-term target of sustainable development, it seems to be important to specify the feasible level of car ownership and travel demand from environmental considerations. This research intends to propose an integrated modeling framework for optimal construction of a comprehensive transportation system by taking into consideration environmental constraints. The modeling system is actually a combination of multiple essential models and illustrated by using a bi-level programming approach. In the upper level, the maximization of both total car ownership and total number of trips by private and public travel modes is set as the objective function and as the constraints, the total emission levels at all the zones are set to not exceed the relating environmental capacities. Maximizing the total trips by private and public travel modes allows policy makers to take into account trip balance to meet both the mobility levels required by travelers and the environmentally friendly transportation system goals. The lower level problem is a combined trip distribution and assignment model incorporating traveler's route choice behavior. A logit-type aggregate modal split model is established to connect the two level problems. In terms of the solution method for the integrated model, a genetic algorithm is applied. A case study is conducted using road network data and person-trip (PT) data collected in Dalian city, China. The analysis results showed that the amount of environmentally efficient car ownership and number of trips by different travel modes could be obtained simultaneously when considering the zonal control of environmental capacity within the framework of the proposed integrated model. The observed car ownership in zones could be increased or decreased towards the macroscopic optimization objective with zonal limit of emissions. © 2008 International Association of Traffic and Safety Sciences.},

keywords = {Bi-level programming, Car ownership, Environmental capacity, Genetic algorithm, Integrated model, Trip balance},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2007,

title = {Modelling the level of environmentally efficient car ownership},

author = {T Feng and Junyi Zhang and Akimasa Fujiiwara},

doi = {10.11175/easts.7.1490},

issn = {1881-1124},

year  = {2007},

date = {2007-01-01},

journal = {Journal of the Eastern Asia Society for Transportation Studies},

volume = {7},

issue = {2007},

pages = {1490 – 1505},

abstract = {This study attempts to develop a macro-level car ownership model using a bi-level optimization modeling approach. The upper level of the bi-level model deals with a maximum problem of zonal car ownership. Objective function is the total zonal car ownership and the constraints are the legalized standard of air quality and the frontier emissions estimated using a stochastic frontier analysis approach. The lower level is a user equilibrium assignment model. Pollutant concentrations are estimated using an artificial neural network model. The interdependencies of car ownership, traffic flow, and the emissions and pollutant concentrations are logically represented based on an iterated optimization process. The final optimized car ownership can be used as a benchmark of realizing environmentally sustainable transportation systems. Based on the data collected in Dalian, China and the Millennium Cities Database, the effectiveness of the proposed car ownership model was empirically confirmed.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Feng2007b,

title = {Environmental efficiency analysis of transportation system: a stochastic frontier approach with flexible cause-effect structure},

author = {T Feng and Junyi Zhang and Akimasa Fujiiwara},

doi = {10.11175/easts.7.1475},

issn = {1881-1124},

year  = {2007},

date = {2007-01-01},

journal = {Journal of the Eastern Asia Society for Transportation Studies},

volume = {7},

issue = {2007},

pages = {1475 – 1489},

abstract = {This paper aims to evaluate environmental efficiency of transportation systems by integrating a multiple-output stochastic frontier analysis (SFA) model with a structural equation model (SEM) to flexibly incorporate cause-effect relationships among various factors influencing traffic emissions. The SEM is firstly specified to illustrate such complex interrelations and the calculated latent variables are taken as the inputs to SFA model. A SFA model, named the distance function approach which can accommodate multiple inputs and multiple outputs, is adopted to calculate efficiency scores in transport sectors at different cities. To examine the model performance, an empirical study is carried out considering three types of emissions, i.e., CO, VHC and NOx, based on the Millennium Cities Database. The effectiveness of the proposed model is confirmed. Efficiencies in transport sectors are compared and it is found that cities in developed countries do not consistently show higher efficiency than other developing cities.},

keywords = {Environmental efficiency, Multi-output stochastic frontier analysis (SFA), Structural equation model (SEM)},

pubstate = {published},

tppubtype = {article}

}

@article{Yang2006,

title = {Forecast on maximum car ownership with constraint of environmental capacity in urban},

author = {Z. -Z. Yang and G. -Q. Miao and T. Feng},

issn = {10017372},

year  = {2006},

date = {2006-01-01},

journal = {Zhongguo Gonglu Xuebao/China Journal of Highway and Transport},

volume = {19},

issue = {6},

abstract = {A model which is a bi-level optimal problem and can forecast the maximum car ownership in urban with constraint of urban environmental capacity was developed. The upper level maximizes the car ownership subjected to the environmental capacity constraint, where the objective function is the maximum of the sum of zonal car population and constraints are environmental capacities on all links. The lower level assigns the OD traffic on road network with user equilibrium method, which simulates the behaviors of traveller path selection and forecasts distribution and running characteristics of traffic demand on road network. In order to realize the feedback between the two levels and solve two optimization problem simultaneously, an algorithm based on sensitivity analysis was developed and a numerical test was used to verify the effectiveness of model and algorithm.},

keywords = {Bi-level programming model, Car ownership, Sensitivity analysis, Traffic engineering, Traffic environmental capacity, Traffic volume assignment},

pubstate = {published},

tppubtype = {article}

}

@article{Yang2005,

title = {Maximizing car ownership under constrains of environment sustainability in a city},

author = {Z (Zhongzhen) Yang and T Feng and Peng Jia},

doi = {10.11175/easts.6.3077},

issn = {1881-1124},

year  = {2005},

date = {2005-01-01},

journal = {Journal of the Eastern Asia Society for Transportation Studies},

volume = {6},

issue = {2005},

pages = {3077 – 3089},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {[No title]},

keywords = {},

pubstate = {published},

tppubtype = {article}

}