Yaping Zhang

Congestion Pricing for Aircraft Pushback Slot Allocation.

In order to optimize aircraft pushback management during rush hour, aircraft pushback slot allocation based on congestion pricing is explored while considering monetary compensation based on the quality of the surface operations. First, the concept of the “external cost of surface congestion” is proposed, and a quantitative study on the external cost is performed. Then, an aircraft pushback slot allocation model for minimizing the total surface cost is established. An improved discrete differential evolution algorithm is also designed. Finally, a simulation is performed on Xinzheng International Airport using the proposed model. By comparing the pushback slot control strategy based on congestion pricing with other strategies, the advantages of the proposed model and algorithm are highlighted. In addition to reducing delays and optimizing the delay distribution, the model and algorithm are better suited for use for actual aircraft pushback management during rush hour. Further, it is also observed they do not result in significant increases in the surface cost. These results confirm the effectiveness and suitability of the proposed model and algorithm.

Theory of Allocating and Scheduling Resources at Airport Passenger Terminals: A Review

This paper reviews theory of allocating and scheduling resources at airport passenger terminals, from three aspects, that are method of integrating airport operational data, method of predicting passenger flow at airport terminals and optimization method of allocating and scheduling resources at airport terminals. Directions and challenges of future research are identified.

Analysis on Adhesion Coefficient of Ice and Snow Pavement

The number of traffic accidents caused by ice and snow is generally three to four times higher than that in normal condition. In order to improve safety level when driving on ice and snow pavement, adhesion coefficient is a vital parameter need to be analyzed. The relations between adhesion coefficient and temperature, relative humidity, snow’s thickness, snow’s compactness were studied. And their relation models were established. These models may provide the basis for the road administration department to conduct traffic control decision-making according to the weather condition and the state of ice and snow.

A Flight Ground-waiting Time Threshold Optimization Model

The number of flight is increasing sharply with sustainable development of civil aviation enterprise in China, which causes a lot of fuel consumption and pollution emissions in the process of launching control, aircraft taxiing and taking off. Unreasonable waiting arrangement will also reduce the comfort of the passengers, which leads to the economic losses of air transport. By analyzing the process of flight, it was found that each flight would experience the queuing twice before entering the taxiway and at the end of the taxiway, respectively. In this study, a few key time parameters were determined to calculate the arrival rate and service time during the two queuing process, including flight pushback time (FPT), taxiway entrance service time (TEST), arrival time of taxiway queue (ATTQ), and runway service time (RST). The statistical distribution fitting test was conducted to determine the best distributions for the four key time parameters mentioned above. By putting corresponding formula of arrival rate and service time in tandem queuing basic model, the calculation formula of average waiting time, average service time and average residence time of two-level tandem queuing system were also inferred. Based on the optimization theory, this paper established a flight waiting time threshold optimization model. The optimization goal of this model is minimize the upper and lower bounds of the threshold value. And the constraint conditions of this model include wake turbulence separation and taxiway length, which setting concerned with the scale of the airport, the airport land arrangement, taxiway capacity, and number of flights and so on. The genetic algorithm was applied to solve this model. A case study showed that flight waiting time was obviously reduced after optimization.

Research on Timing Optimization for Signalized Intersections under Ice and Snowfall Conditions Based on the Queue Matrix

Ice and snow are common in the south of China and have quite a large effect on the signalized intersection traffic capacity. From the angle of signal control of signalized intersections, the paper studies the optimization methods of signal cycle time, green split and yellow light time. Taking the queue length under ice and snowfall conditions as the judging criteria, this paper introduces the judgment matrix needed to be optimized at the signalized intersection to identify the optimization scheme of cycle time and green light time in signal timing under ice and snowfall conditions. Meanwhile, this paper makes the empirical research based on the data of typical intersections -- Songshan Road-Huaihe Road and Hongqi Road-Huaihe Road in Harbin -- and the results show that the optimized signalized intersection traffic capacity under ice and snowfall conditions have been improved.

A Fuzzy Control Algorithm on Aircraft Pushback Time Sequence

From analysis of the flight departure process in an airport, this paper studied the behavioral characteristics of the departure process and built its model. Combined with the theory of fuzzy control, an algorithm of aircraft pushback control was given and the internal rules of fuzzy control were discussed. Using the Matlab/Simulink software, a simulation process was built to do a simulation experiment. Finally, the paper demonstrated the effectiveness of the fuzzy control algorithm and the scheme by comparing the simulation data with the actual data.

Chaotic Characteristics Identification on Terminal Departing Passenger Traffic Time Series

On the basis of actual survey of departing passengers to reach terminal, chaotic time series prediction theory was adopted for data analysis in this paper. In order to find out the self-similarity of time series, this paper divided passenger traffic into two kinds: holiday traffic and non-holiday traffic by changing interval scale. The optimal delay time and the best embedding dimension had been calculated by using time series phase space reconstruction method. To confirm whether the time series have chaotic characteristics or not, it took the largest Lyapunov exponent as determining criterion.Then the optimal time intervals of passenger traffic time series with chaotic character were determined. The study provides a theoretical basis for the application of chaos theory in passenger traffic forecast.

A Pushback Slot Allocation Equilibrium Model Based on Game Theory

This paper analyses the relationship between airport and airline, the time slot allocation system is portrayed as a market where the airline can be seen as consumer, airport can be seen as the trader and the goods is the occupied pushback slots of airport. In that case, the generalized nash equilibrium game is presented based on game theory. Taking the Minimize delay as a target, a decision models of airport was established. The pushback slot allocation equilibrium model based on game theory is finnally formed, and a framework for solving the equilibrium solution is proposed.

Analysis on Capacity and LOS of Signalized Intersection in Slight Snowy Weather

In order to evaluate traffic operation status of signalized intersection in slight snowy weather, it was studied that the influence of slight snow on capacity and level of service (LOS) of signalized intersection. Data of timing, vehicle’s starting loss time, saturated headway of straight vehicle and delay of one signalized intersections in sunny and slight snowy weather were observed by video method. Stop-line method was adopted to calculate the capacity of signalized intersection and LOS was evaluated by American standard. It showed that capacity of signalized intersection decreased by 7% and LOS declined one level in slight snowy weather compared with on sunny weather.

Influences of Ice-Snow on Capacity of Signalized Intersection and the Minimum Green Time

In order to evaluate traffic operation status of signalized intersection and improve pedestrian traffic safety under the condition of ice-snow, it was studied that the influence of ice-snow on capacity of signalized intersection and the minimum green time. Saturated headway data of nine signalized intersections were observed by video method. And the influence of ice-snow melting pavement, compacted partly snowy pavement, compacted snowy pavement and normal pavement on saturated flow rate of signalized intersection were analyzed respectively. Correction coefficients of capacity of signalized intersection on different ice-snow pavement were given. Pedestrian’s crossing speed at nine signalized intersection on snowy pavement, icy pavement and normal pavement were observed and compared. And then the suggestion values of minimum green time calculation parameter were put forward.