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Edmund K Burke - One of the best experts on this subject based on the ideXlab platform.
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Airport Ground Movement: Real World Data Sets and Approaches to Handling Uncertainty
2020Co-Authors: John R. Woodward, Edmund K BurkeAbstract:1 Abstract Two related topics are considered in this presentation, both concerning the Ground Movement of aircraft. The first describes the collection of data from publicly available websites and the second discusses the issue of uncertainty in this problem. The airport Ground Movement problem [1] connects together the problems of runway scheduling and gate allocation, which are often tackled separately in the research literature. The overall problem involves allocating routes for aircraft to take as they proceed along the taxiways between the runways and the gates (stands), and timings or orders for them to take them. The aim is to find a schedule that reduces delays, reduces the fuel burn associated with taxiing, and is resilient to last-minute changes. This represents a challenging problem because there are typically several pinch points where congestion is more likely to occur, and the uncertainty inherent in aircraft landing times, pushback times and taxi speeds means that routes need to be constantly updated to reflect the current situation. In addition, any solution method must be efficient enough that it can be executed within a couple of minutes, at most, to accommodate incoming, changing data. Furthermore, once an aircraft has had a route allocated and commenced its Movement, it is undesirable (and
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a fuzzy approach to addressing uncertainty in airport Ground Movement optimisation
Transportation Research Part C-emerging Technologies, 2018Co-Authors: Alexander E I Brownlee, Michal Weiszer, Jun Chen, Stefan Ravizza, John R. Woodward, Edmund K BurkeAbstract:Abstract Allocating efficient routes to taxiing aircraft, known as the Ground Movement problem, is increasingly important as air traffic levels continue to increase. If taxiways cannot be reliably traversed quickly, aircraft can miss valuable assigned slots at the runway or can waste fuel waiting for other aircraft to clear. Efficient algorithms for this problem have been proposed, but little work has considered the uncertainties inherent in the domain. This paper proposes an adaptive Mamdani fuzzy rule based system to estimate taxi times and their uncertainties. Furthermore, the existing Quickest Path Problem with Time Windows (QPPTW) algorithm is adapted to use fuzzy taxi time estimates. Experiments with simulated taxi Movements at Manchester Airport, the third-busiest in the UK, show the new approach produces routes that are more robust, reducing delays due to uncertain taxi times by 10–20% over the original QPPTW.
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a combined statistical approach and Ground Movement model for improving taxi time estimations at airports
Journal of the Operational Research Society, 2013Co-Authors: Stefan Ravizza, Jason A D Atkin, Marloes H Maathuis, Edmund K BurkeAbstract:With the expected continued increases in air transportation, the mitigation of the consequent delays and environmental effects is becoming more and more important, requiring increasingly sophisticated approaches for airside airport operations. Improved on-stand time predictions (for improved resource allocation at the stands) and take-off time predictions (for improved airport-airspace coordination) both require more accurate taxi time predictions, as do the increasingly sophisticated Ground Movement models which are being developed. Calibrating such models requires historic data showing how long aircraft will actually take to move around the airport, but recorded data usually includes significant delays due to contention between aircraft. This research was motivated by the need to both predict taxi times and to quantify and eliminate the effects of airport load from historic taxi time data, since delays and re-routing are usually explicitly considered in Ground Movement models. A prediction model is presented here that combines both airport layout and historic taxi time information within a multiple linear regression analysis, identifying the most relevant factors affecting the variability of taxi times for both arrivals and departures. The promising results for two different European hub airports are compared against previous results for US airports.
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the airport Ground Movement problem past and current research and future directions
2010Co-Authors: Jason A D Atkin, Edmund K Burke, Stefan RavizzaAbstract:Determining efficient airport operations is an impor- tant and critical problem for airports, airlines, passengers and other stakeholders. Moreover, it is likely to become even more so given the traffic increases which are expected over the next few years. The Ground Movement problem forms the link between other airside problems, such as arrival sequencing, departure sequencing and gate/stand allocation. This paper provides an overview, categorisation and critical examination of the previous research for Ground Movement and highlights various important open areas of research. Of particular importance is the ques- tion of the integration of various airport operations and their relationships which are considered in this paper. Index Terms —Airside airport operations, Ground Movement, taxiing, survey, future work, integration of airport operations.
Li Ning - One of the best experts on this subject based on the ideXlab platform.
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Ground Movement Laws Caused by the Tunnel Lining Deformation
Journal of Xi'an University of Technology, 2020Co-Authors: Han Xuan, Li NingAbstract:The numerical analysis method is used to study the Ground Movement laws caused by the ovalization variation in the cross section in the action of water and soil pressure of tunnel lining.Based on the stochastic medium theory,this paper suggests the method for calculating this Ground Movement caused by tunnel ovalization deformation.The suggested method is described via the real example calculations.Also,it is pointed out that the Ground Movement caused by the lining pressure deformation is one of the important causes of the landsurface settlement chute that divagates from Gauss distribution laws.
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Study on subsurface Ground Movement caused by urban tunneling
Rock and Soil Mechanics, 2020Co-Authors: Li NingAbstract:The research on subsurface Ground Movement has a great importance in terms of the evaluation of the risks to the subsurface structures and pipelines influenced by tunneling.However,this is a topic about which is little known.According to the research by Mair et al(1993) who analyzed the subsurface data from various tunneling projects and centrifuge tests in clays,subsurface settlement profiles could also be reasonably approximated by the form of a Gaussian distribution in the same way as surface settlement profiles.Their equation based on this observation is widely used.However,a fixed value for surface settlement trough-width parameters K is used for clay in the equation,which causes considerable errors for different geological conditions.Also,because of the data they used,Mair equation is only applicable to clays.Based on field data analysis,a normalized ratio ηd is suggested in this paper to account for the different geological conditions;and a modified Mair equation is established which is not only suitable for the cases surface settlement trough with different width parameters,but also can be used for sands.Thus this modified general expression can be used to predict the subsurface Ground Movement with a broader adaptability compared with the original Mair equation.
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A predicting model for Ground Movement induced by non-uniform convergence of tunnel
Chinese Journal of Geotechnical Engineering, 2020Co-Authors: Li NingAbstract:Stochastic Medium Model(SMM) was widely used for predicting Ground Movement induced by tunneling in China.A uniform convergence mode was assumed in this model for the transversal section of tunnel after excavation.According to the observed convergence mode of tunnel,a non-uniform convergence mode was introduced to the SMM method to achieve a better prediction of the Ground deformation,and the integral limits for various shapes of cross section,such as the circular,elliptical,rectangular and horse-shoe shaped tunnel were deduced.Based on some case studies,it was found that the uniform convergence assumption cause considerable error for shallow tunnels,so it was important to consider a proper convergence mode to take into account the influence of deformation condition and construction techniques of the tunnel.
Stefan Ravizza - One of the best experts on this subject based on the ideXlab platform.
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a fuzzy approach to addressing uncertainty in airport Ground Movement optimisation
Transportation Research Part C-emerging Technologies, 2018Co-Authors: Alexander E I Brownlee, Michal Weiszer, Jun Chen, Stefan Ravizza, John R. Woodward, Edmund K BurkeAbstract:Abstract Allocating efficient routes to taxiing aircraft, known as the Ground Movement problem, is increasingly important as air traffic levels continue to increase. If taxiways cannot be reliably traversed quickly, aircraft can miss valuable assigned slots at the runway or can waste fuel waiting for other aircraft to clear. Efficient algorithms for this problem have been proposed, but little work has considered the uncertainties inherent in the domain. This paper proposes an adaptive Mamdani fuzzy rule based system to estimate taxi times and their uncertainties. Furthermore, the existing Quickest Path Problem with Time Windows (QPPTW) algorithm is adapted to use fuzzy taxi time estimates. Experiments with simulated taxi Movements at Manchester Airport, the third-busiest in the UK, show the new approach produces routes that are more robust, reducing delays due to uncertain taxi times by 10–20% over the original QPPTW.
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A heuristic approach to greener airport Ground Movement
2014 IEEE Congress on Evolutionary Computation (CEC), 2014Co-Authors: Michal Weiszer, Jun Chen, Stefan Ravizza, Jason Atkin, Paul StewartAbstract:Ever increasing air traffic, rising costs and tighter environmental targets create a pressure for efficient airport Ground Movement. Ground Movement links other airport operations such as departure sequencing, arrival sequencing and gate/stand allocation and its operation can affect each of these. Previously, reducing taxi time was considered the main objective of the Ground Movement problem. However, this may conflict with efforts of airlines to minimise their fuel consumption as shorter taxi time may require higher speed and acceleration during taxiing. Therefore, in this paper a multi-objective multi-component optimisation problem is formulated which combines two components: scheduling and routing of aircraft and speed profile optimisation. To solve this problem an integrated solution method is adopted to more accurately investigate the trade-off between the total taxi time and fuel consumption. The new heuristic which is proposed here uses observations about the characteristics of the optimised speed profiles in order to greatly improve the speed of the graph-based routing and scheduling algorithm. Current results, using real airport data, confirm that this approach can find better solutions faster, making it very promising for application within on-line applications.
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IEEE Congress on Evolutionary Computation - A heuristic approach to greener airport Ground Movement
2014 IEEE Congress on Evolutionary Computation (CEC), 2014Co-Authors: Michal Weiszer, Jun Chen, Stefan Ravizza, Jason A D Atkin, Paul StewartAbstract:Ever increasing air traffic, rising costs and tighter environmental targets create a pressure for efficient airport Ground Movement. Ground Movement links other airport operations such as departure sequencing, arrival sequencing and gate/stand allocation and its operation can affect each of these. Previously, reducing taxi time was considered the main objective of the Ground Movement problem. However, this may conflict with efforts of airlines to minimise their fuel consumption as shorter taxi time may require higher speed and acceleration during taxiing. Therefore, in this paper a multi-objective multicomponent optimisation problem is formulated which combines two components: scheduling and routing of aircraft and speed profile optimisation. To solve this problem an integrated solution method is adopted to more accurately investigate the trade-off between the total taxi time and fuel consumption. The new heuristic which is proposed here uses observations about the characteristics of the optimised speed profiles in order to greatly improve the speed of the graph-based routing and scheduling algorithm. Current results, using real airport data, confirm that this approach can find better solutions faster, making it very promising for application within on-line applications.
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a combined statistical approach and Ground Movement model for improving taxi time estimations at airports
Journal of the Operational Research Society, 2013Co-Authors: Stefan Ravizza, Jason A D Atkin, Marloes H Maathuis, Edmund K BurkeAbstract:With the expected continued increases in air transportation, the mitigation of the consequent delays and environmental effects is becoming more and more important, requiring increasingly sophisticated approaches for airside airport operations. Improved on-stand time predictions (for improved resource allocation at the stands) and take-off time predictions (for improved airport-airspace coordination) both require more accurate taxi time predictions, as do the increasingly sophisticated Ground Movement models which are being developed. Calibrating such models requires historic data showing how long aircraft will actually take to move around the airport, but recorded data usually includes significant delays due to contention between aircraft. This research was motivated by the need to both predict taxi times and to quantify and eliminate the effects of airport load from historic taxi time data, since delays and re-routing are usually explicitly considered in Ground Movement models. A prediction model is presented here that combines both airport layout and historic taxi time information within a multiple linear regression analysis, identifying the most relevant factors affecting the variability of taxi times for both arrivals and departures. The promising results for two different European hub airports are compared against previous results for US airports.
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Enhancing Decision Support Systems for Airport Ground Movement
2013Co-Authors: Stefan RavizzaAbstract:With the expected continued increases in air transportation, the mitigation of the consequent delays and environmental effects is becoming more and more important, requiring increasingly sophisticated approaches for airside airport operations. The Ground Movement problem forms the link between other airside problems at an airport, such as arrival sequencing, departure sequencing, gate/stand allocation and stand holding. The purpose of this thesis is to contribute to airport Ground Movement research through obtaining a better understanding of the problem and producing new models and algorithms for three sub-problems. Firstly, many stakeholders at an airport can benefit from more accurate taxi time predictions. This thesis focuses upon this aim by analysing the important factors affecting taxi times for arrivals and departures and by comparing different regression models to analyse which one performs the best for this particular task. It was found that incorporating the information of the airport layout could significantly improve the accuracy and that a TSK fuzzy rule-based system outperformed other approaches. Secondly, a fast and flexible decision support system is introduced which can help Ground controllers in an airport tower to make better routing and scheduling decisions and can also absorb as much of the waiting time as possible for departures at the gate/stand, to reduce the fuel burn and environmental impact. The results show potential maximum savings in total taxi time of about 30.3%, compared to the actual performance at the airport. Thirdly, a new research direction is explored which analyses the trade-off between taxi time and fuel consumption during taxiing. A sophisticated new model is presented to make such an analysis possible. Furthermore, this research provides the basis for integrating the Ground Movement problem with other airport operations. Datasets from Zurich Airport, Stockholm-Arlanda Airport, London Heathrow Airport and Hartsfield-Jackson Atlanta International Airport were utilised to test these sub-problems.
Congxin Chen - One of the best experts on this subject based on the ideXlab platform.
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investigation of the Ground Movement due to underGround mining at the jinshandian iron mine in china
Environmental Earth Sciences, 2019Co-Authors: Congxin Chen, Zude Lu, Kuoyu Yang, Yun Zheng, Hansong PangAbstract:To investigate the mechanism responsible for mining-induced Ground Movement at the Jinshandian Iron Mine in China, the vertical and horizontal deformations of the Ground-surface were monitored in situ over a period of 8 years. The results were analyzed and combined with subsidence results derived from laser-scanning measurements and collapse/cracking behavior of the Ground. The results show that the horizontal displacement mainly occurs in the rock masses surrounding the mined voids. Moreover, several obvious onset points can be found in the displacement–time curves that are indicative of rapid increases in displacement. Currently, the scope of the Ground Movement of the footwall is larger than that of the hanging wall. This behavior is distinctive and distinguishes the Jinshandian Iron Mine from others. It can be attributed to the sliding–toppling failure of the column-shaped rock masses in the footwall under the combined effect of the in situ horizontal stress and high dip angles of the discontinuities.
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Ground Movement mechanism in tectonic stress metal mines with steep structure planes
Journal of Central South University, 2017Co-Authors: Congxin Chen, Yuan Zheng, Hua FuAbstract:When mining metal mines with steep structure planes by the caving method, there is a mechanical model in which the horizontal stress on the rock mass is simplified as a column before surface subsidence. The model is used to deduce critical support load and limiting column length for a given horizontal stress and support pressure. Considering the impact of the column effect, a method is proposed to determine the Movement of the Ground and caving area in a mine. After surface subsidence, the horizontal stress on a surrounding rock mass can be simplified to a cantilever beam mechanical model. Expressions for its bending fracture length are deduced, and a method is given to determine its stability. On this basis, an explanation for the large Ground Movement and subsidence scope was given. A case study shows that the damage effect of column and cantilever beam is significant for Ground Movement in metal-ore mine, and an appropriate correction value should be applied when designing for its angle of Ground Movements.
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mining induced Ground Movement in tectonic stress metal mines a case study
Bulletin of Engineering Geology and the Environment, 2016Co-Authors: Congxin Chen, Hua Fu, Yangyang DengAbstract:In-situ monitoring data for horizontal and vertical displacements in the Chenchao Iron Mine were collected over an eight-year period. The results were analysed to investigate Ground Movements induced by underGround mining: large-scale Ground deformation was found in mining areas of the footwall, and the angle of Ground Movement in the footwall was lower (by approximately 10°–14°) than that in the hanging wall. This was attributed to the combined response to the geomechanical setting of the orebody, many groups of structure planes, and in-situ stresses under the area of underGround mining in the footwall, which generates Ground Movement by an “onlap effect”. When a fracture plane forms in a deep rock mass, then the mining-induced Ground Movement area is divided into: a toppling-sliding zone, a toppling zone, and a stability zone. Eventually, correction factors for the influence of the in-situ stress and major structure plane on the angle of Ground Movement in metal mines are given, as the “onlap hanging” structure exists in the footwall of the mine, which required a correction of between 10° and 15° in the northeastern part on the basis of the original angle of Ground Movement, and in the northern part, of between 5° and 10°.
Yutaka Fukumoto - One of the best experts on this subject based on the ideXlab platform.
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Group effect on ultimate lateral resistance of piles against uniform Ground Movement
Soils and Foundations, 2019Co-Authors: Quang N. Pham, Satoru Ohtsuka, Koichi Isobe, Yutaka FukumotoAbstract:Abstract In earthquake engineering, pile foundations are designed to withstand the lateral loading that results from large displacements due to Ground Movement caused by strong earthquakes. The distress and failure of superstructures occurs when the lateral load exceeds the ultimate lateral resistance of the piles. The aim of this study is to estimate the ultimate lateral resistance of piles especially in terms of the group effect induced by the pile arrangement. Several experimental and numerical analyses have been conducted on pile groups to investigate the group effect when the groups are subjected to uniform large horizontal Ground Movement. However, the ultimate lateral resistance of the pile groups in these studies was calculated by applying load to the piles. The present study directly assesses the ultimate lateral resistance of pile groups against Ground Movement by systematically varying the direction of the Ground Movement. Although the load bearing ratio of each pile in a pile group, defined as the ratio of the ultimate lateral resistance of each pile in a pile group to that of a single pile, is an important design criterion, it was difficult to assess in past works. This study focuses on the load bearing ratio of each pile against Ground Movement in various directions. The use of the finite element method (FEM) provides options for simulating the pile-soil system with complex pile arrangements by taking the complicated geometry of the problem into account. The ultimate lateral resistance is examined here for pile groups consisting of a 2 × 2 arrangement of four piles, as well as two piles, three piles, four piles, and an infinite number of piles arranged in a row through case studies in which the pile spacing is changed by applying the two-dimensional rigid plastic finite element method (RPFEM). The RPFEM was extended in this work to calculate not only the total ultimate lateral resistance of pile groups, but also the load bearing ratio of the piles in the group. The obtained results indicate that the load bearing ratio generally increases with an increase in pile spacing and converges to almost unity at a pile spacing ratio of 3.0 with respect to the pile diameter. Moreover, the group effect was further investigated by considering the failure mode of the Ground around the piles.
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Ultimate Lateral Resistance of Pile Group in Clayey Soils Against Various Directions of Ground Movement
Lecture Notes in Civil Engineering, 2018Co-Authors: Quang N. Pham, Satoru Ohtsuka, Koichi Isobe, Yutaka FukumotoAbstract:This study estimated the ultimate lateral resistance of pile group against horizontal Ground Movement by using two-dimensional rigid plastic finite element method (RPFEM). The effect of Ground Movement direction on the ultimate lateral resistance was investigated through the case studies. According to the results, it can be seen that changes in both the ultimate lateral resistance and the failure mode of Ground around piles were observed. The effect of the pile spacing on load apportionment ratios was studiously investigated. Since each pile in the group affects other piles, it leads the load apportionment ratio significantly to depend on pile positions such as the front or back piles. Moreover, the load apportionment ratio of each pile went up with an increase in pile spacing, but it was obtained different remarkably among piles. The load apportionment ratio varied with the direction of the Ground Movement.
