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The aim of this study is to identify the nodes where congestion occurs in the manoeuvring area of a large-scale airport and to provide appropriate suggestions for improvement.

To investigate the air traffic flow in a highly complex system such as an airport manoeuvring area, a two-stage method based on fast- and real-time simulation techniques is applied. The first stage involves the analysis with fast- and real-time simulations of a baseline model created to determine the congestion points. Based on the analysis, improvements to be performed in the layout of the manoeuvring area are proposed. In the second stage, alternative scenarios implementing these improvements are generated and evaluated in a fast-time simulation environment. Based on the results of simulations of different runway configurations, the main areas of congestion in the baseline airport model are determined. Congestion nodes are identified in the departure queue points and in the taxiway system. To mitigate congestion at these points, three alternative models comprising taxiway and fast-exit taxiway reconfigurations are tested using the fast-time simulation technique. The alternative solution found to be the best in these tests is selected for further testing in real-time simulations.

It is shown that the solution would result in an increase in the number of hourly operations and a significant decrease in total ground delays. When conducting the studies needed to identify congestion and design improvements, simulation techniques save both expense and time. Although fast-time simulations are usually adequate for identifying solutions, when critical configurations for the airport are considered, it is shown that it is necessary to also test the results of the fast-time simulations in real-time simulations.

The effects of meteorological events, such as rain, fog and snow, etc. are ignored in the simulations. Ground movements in manoeuvring areas are significantly affected by the runways used. Consequently, to enable a comprehensive evaluation in the study, three alternative runway use scenarios are examined.

This study utilizes a combination of fast- and real-time simulation techniques to identify the points where congestion occurs in the manoeuvring areas of large-scale airports and to find solutions to minimize the congestion. This approach attempts to combine advantages of both techniques while reducing their shortcomings. No study is found in the literature using both of these techniques together for the capacity analysis of airport manoeuvring areas.

The paper aims to present the findings of a research project “Human Factors in ‘Fast‐Time’ Simulation” which was supported by Central European Air Traffic Services – CEATS Research, Development and Simulation Centre (CRDS) EUROCONTROL.

With the aim of improving fast‐time simulations by developing new models related to the air traffic controller's decisions, a simple traffic situation was chosen. It is focused on a pair of aircraft where one aircraft is cruising while the second is requesting clearance for climbing to the same flight level and proceeding flight “in‐trail” whereby flight level is not occupied with other traffic.

In order to determine parameters important to the controllers while making a decision, pilot inquiry was realized in the EUROCONTROL CRDS. The results obtained were used for determining the content and form of the final interview. The model based on the final interview results is designed on the “black box” principle – for certain inputs, output is a two‐dimensional decision: YES/NO give the clearance to the aircraft to climb. The model coincides to a high degree with the real system, confirming its credibility.

The established model could improve fast‐time simulations. By defining all relevant traffic situations, developing rule bases for every day traffic situations will be possible. Those rule bases could cover mayor situations which controllers are often confronted with. Integration of the model into fast‐time simulators could improve the credibility of simulated air traffic to the real traffic system.

The paper deals with the various aspects of human factor modelling in aviation.

The purpose of this paper was to elaborate the performance model of the remotely piloted aircraft systems (RPAS) which was destined for simulations of the construction characteristics, airspeeds and trajectory of flight in the controlled, non-segregated airspace according to the standard instrument departure and arrival procedures (SIDs and STARs).

This study used systems engineering approach: decomposition of RPAS performance model into components, relations and its connection with components of controlled the airspace system. Fast-time simulations (FTS) method, which included investigation of many scenarios of the system work, minimizing the number of input variables and low computing power demand, is also used.

Performance envelope of many fixed-wing RPAS was not published. The representative RPAS geometry configuration was feasible to implement. Power unit model and aerodynamic model needed to be accommodated to RPAS category. The range of aircraft minimum drag coefficient differed in the investigated range of take-off mass and wing loading.

Fixed-wing RPAS of small and medium categories cover take-off mass (25–450 kg), wing loading (40–900 N/m²) and power loading (8–40 W/N).

This is a research on integration of the RPAS in the controlled, non-segregated airspace. The results of the work may be used in broadening the knowledge of the RPAS characteristics from the perspective of operators, designers and air traffic services.

The elaborated performance model of the RPAS used the minimum number of three input variables (take-off mass, wing loading and power loading) in identification of the complete RPAS characteristics, i.e. construction features (aerodynamic, propulsion and loads) and flight parameters (airspeeds and flight trajectory).

The aim of the paper is to investigate the impacts of simplifications of a reduced-order simulation model of squirrel cage induction machines (SCIMs) by numerical experiments.

Design of setups to isolate the main influences on the results of the reduced-order model of SCIMs. Results of time-stepping finite element calculations are used as benchmark.

Whereas neglecting eddy current effects and the assumption of a sinusoidal rotor current distribution leads to acceptable deviations in regular inverter operation, the sampling and interpolation of the machine parameters in a two-axis coordinate system considerably deteriorate the model accuracy. Using a polar coordinate system for this purpose is expected to significantly improve the model quality.

Preparing the ground for a successful, both fast and accurate simulation model of SCIMs as parts of electrified drivetrains.

The purpose of this paper is to provide a minimum time algorithm to intercept an object on a conveyor belt by a robotic manipulator. The goal is that the robot is able to intercept objects on a conveyor line moving at a given speed in minimum time.

In order to formulate the problem, the robot and object‐arrival time functions were introduced, and conclude that the optimal point occurs at the intersection of these two functions. The search algorithm for finding the intersection point between the robot and object arrival time functions are also presented to find the optimal point in real‐time.

Simulation results show that the presented algorithm is well established for various initial robot positions.

A trapezoidal velocity profile was employed which is used in many industrial robots currently in use. Thus, it is believed that robot travel time algorithm is readily implemented for any commercially available robots.

The paper considers exhaustive cases where robot travel time functions are dependent upon initial positions of robotic end‐effectors. Also presented is a fast converging search algorithm so that real time application is more feasible in many cases.

The purpose of this paper is to create and analyze the effectiveness of a new runway system, which is totally created for the future free route operations.

This paper researches and analyses the new generated runway concept with the fast time simulation method. Fuel consumption and environmental effect of the new runway system are calculated based on simulation results.

According to different traffic density analyses the Omnidirectional Runway with Infinite Heading (ORIH) reduced fuel consumption and CO₂ emissions up to 46.97%. Also the total emissions of the ORIH concept, for the hydro carbon (HC), carbon monoxide (CO) and nitrogen oxides (NOx) pollutants were lower than the total emissions with the conventional runway up to 83.13, 74.36 and 51.49%, respectively.

Free route airspaces bring many advantages to air traffic management and airline operations. Direct routes become available from airport to airport thanks to free route airspace concept. However, conventional single runway structure does not allow aircraft operations for every direction. The landing and take-off operations of a conventional airport with a single runway must be executed with only two heading direction. This limitation brings a bottleneck direct approach and departure route usage as convenient with free route airspace concept. This paper suggests and analyzes the omnidirectional runway with infinite heading (ORIH) as a solution for free route airspace.

This paper suggests a new and futuristic runway design and operation for the free route operations. This paper has its originality from the suggested and newly created runway system.

Discretizing the magnetic vector potential formulation of eddy current problems in space results in an infinitely stiff differential algebraic equation system that is integrated in time using implicit time integration methods. Applying a generalized Schur complement to the differential algebraic equation system yields an ordinary differential equation (ODE) system. This ODE system can be integrated in time using explicit time integration schemes by which the solution of high-dimensional nonlinear algebraic systems of equations is avoided. The purpose of this paper is to further investigate the explicit time integration of eddy current problems.

The resulting magnetoquasistatic Schur complement ODE system is integrated in time using the explicit Euler method taking into account the Courant–Friedrich–Levy (CFL) stability criterion. The maximum stable CFL time step can be rather small for magnetoquasistatic field problems owing to its proportionality to the smallest edge length in the mesh. Ferromagnetic materials require updating the reluctivity matrix in nonlinear material in every time step. Because of the small time-step size, it is proposed to only selectively update the reluctivity matrix, keeping it constant for as many time steps as possible.

Numerical simulations of the TEAM 10 benchmark problem show that the proposed selective update strategy decreases computation time while maintaining good accuracy for different dynamics of the source current excitation.

The explicit time integration of the Schur complement vector potential formulation of the eddy current problem is accelerated by updating the reluctivity matrix selectively. A strategy for this is proposed and investigated.

An analytical approach is preferred to carry out the harmonic modelling of power electronics converters because it is generally faster than time simulation chained with FFT. However, the difficulty of such an approach is to build the model and to manage the uncontrolled commutations that occur in the studied static converter, and also to deal with large equations. The purpose of this paper is to propose an aid in the frequency modelling of the drive elements, in the frequency domain, including all key parameters for sizing aim i.e. a way to optimize the EMC filter using different algorithms.

The paper aims to propose an aid to create such models, and to assure its good solving, i.e. that the correct operating mode is represented. So, the solving problem is formulated as an optimization problem under constraints, to solve this difficulty.

The difficulty is to be sure to deal with the good operating mode of the static converter when soft or uncontrolled commutations occur. So, the model is formulated as a constrained optimization problem. The paper proposes a symbolic approach, that allows to build automatically the frequency model. It is translated to be solved in Matlab.

The approach does not fit for static converters with a control implying numerous commutations per operating period. However, the approach deals with natural and soft commutations.

The modelling is based on the use of linear components and ideal switches.

The purpose of this paper is to deal with the design of passive filter for power electronics voltage inverters used in aircraft electrical drives (a permanent magnet synchronous machine fed by a six-phase voltage inverter with PMW control), using optimization for both sizing and sensibility analyses.

The approach is generic. An aid allows to modify easily the frequency model and so to check various study cases, and to carry out the filter optimization for different topologies or control strategies.

The approach is generic. An aid allows to modify easily the frequency model and so to check various study cases, and to carry out the filter optimization for different topologies or control strategies.

The power electronics load is supposed to be a set of predefined harmonic sources, obtained by experiment or time simulation plus fast fourier transformation before the optimization process.

The problem has numerous constraints on the components, mainly technological constraints. The volume is minimized, respecting electromagnetic standards and an electro magnetic interference filter prototype has been made.

The frequency model is automatically generated. A complex aircraft application has been studied thanks to the approach. Several sensibility analyses have been carried out. An EMC filter has been sized and an experimental prototype has been made, comforting the sizing by optimization.

The purpose of this paper is to design a new standard instrument arrival called the point merge system (PMS) for converging runways. The PMS enables controllers to handle traffic with no heading instruction, as well as aiming to reduce a controller's frequency occupancy time.

The point merge model was designed for converging runways. Istanbul International Ataturk Airport, which has converging runways, was chosen as an application area for this model. The same 50 traffic arrivals per hour were used both for point merge and vectoring. Implementation was compared using a real time simulation.

The simulation results show that the total average number of instructions is about 33 per cent less and the frequency occupancy is about 37 per cent less for point merge than for vectoring. In addition, in terms of trajectory dispersion, in point merge, traffic is within a narrower triangular area, while in vectoring large traffic dispersion occurs.

The point merge model for converging runways proposed in this paper can be applied by airspace designers and air navigation service providers to perform efficient standard instrument arrival routes.

The PMS has been developed for single and parallel runways; however, in this study, the point merge model is designed for converging runways at Istanbul International Ataturk Airport.