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Models of the Reference Departure and Arrival IFR Procedures for the Purpose of Research in RPAS Integration in Controlled Airspace

References [1] European Organization for the Safety of the Air Navigation, UAS ATM Integration – Operational Concept , 1 st edition, 2018. [2] European RPAS Steering Group, Roadmap for the integration of civil Remotely-Piloted Aircraft Systems into the European Aviation System , 2013. [3] ICAO, Manual on Remotely Piloted Aircraft Systems (RPAS) , 1 st edition, 2015. [4] ICAO, Procedures for Air Navigation Services – Aircraft Operations (PANS-OPS), Vol. I, Flight Procedures, 5 th edition, 2006. [5] ICAO, Procedures for Air

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Using Floquet Theory in the Procedure for Investigation of the Motion Stability of a Rotor System Exhibiting Parametric and Self-Excited Vibration

Abstract

The computational procedure for investigation vibration stability of a flexible rotor consisting of an asymmetric shaft, one disc, and supported by ball bearings is developed in this work. Lagrange equations of the second kind were used for derivation of the motion equation. The vibration response stability of the Jeffcott-like rotor was studied by means of eigenvalues of a transition matrix. Three different methods for approximation of the transition matrix have been investigated. The presented simulations are focused on studying the influence of parametric excitation produced by the shaft asymmetry and self-excitation vibration caused by the shaft material damping. The numerical results proved the applicability of the developed procedure, which has been verified by the direct integration of the motion equation.

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Integrated Attitude and Navigation System for Small Airplane

Abstract

Navigation system is one of the most important aircraft systems. Accuracy and precision of position and attitude is extremely important for safe aircraft operations. The integrated INS/GNSS systems are commonly used as autonomous on-board devices for fulfilling this task. The INS sensors like accelerometers and gyroscopes are mainly affected by drift. The GNSS encounter stochastic disturbances with no tendency to grow in time but as each radio navigation system may be jammed or its signal can just be not available. These base properties of errors make these two systems well suited for integration. These were the main motivations for development of integrated navigation and attitude determination system, presented in this article. In the developed system, data is integrated from all available sensors, particularly INS, GPS, and air data computer. Navigation information from these sensors is combined using Kalman filtering algorithms to obtain robust solution, effective also in a case of failure/inaccessibility of GPS. Position calculated using the accelerations from INS is corrected by position from GPS and optionally by position calculated using the true airspeed (TAS) from ADC. Navigation system is modelled and programmed in MATLAB environment. The system was tested using the data from real experiments, proving efficiency of the method.

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Soil Load on Plastic Pipe and its Influence on Lifetime

Abstract

Lifetime of plastic pipes can be estimated by integration of a power law describing the crack kinetics. However, this procedure requires an FEM (finite element method) calculation of the possible crack propagation in the pipe to obtain stress intensity factor dependency on the crack length. It is very important for the simulation to consider every possible load that is acting on the pipe. This contribution deals with FEM modelling of a pipe that is loaded by internal pressure, residual stresses and soil loads. Comparison of the factors and pipe lifetime estimation is carried out.

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Response due to mechanical source in second axisymmetric problem of micropolar elastic medium

Abstract

The second axisymmetric problem in a micropolar elastic medium has been investigated by employing an eigen value approach after applying the Laplace and the Hankel transforms. An example of infinite space with concentrated force at the origin has been presented to illustrate the application of the approach. The integral transforms have been inversed by using a numerical technique to obtain the components of microrotation, displacement, force stress and couple stress in the physical domain. The results for these quantities are given and illustratred graphically.

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Response Due to Concentrated Force in Micropolar Elastic Solid with Voids

Abstract

The eigen value approach, following Laplace and Fourier transforms has been employed to find the general solution of the field equation in a micropolar elastic solid with voids for the plane strain problem. An application of an infinite space with impulsive force has been taken to illustrate the utility of the approach. The integral transformations have been inverted by using a numerical inversion technique to get result in physical domain. The result in the form of normal displacement, volume fraction, normal force stress, tangential force stress and tangential couple stress components has been obtained numerically and illustrated graphically to depict the effect of micropolarity and voids.

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Eigen Value Approach in Micropolar Elastic Medium with Voids

The eigen value approach, following the Laplace and Hankel transformation has been employed to find a general solution of the field equations in a micropolar elastic medium with voids for an axisymmetric problem. An infinite space with the mechanical source has been applied to illustrate the utility of the approach. The integral transformations has been inverted by using a numerical inversion technique to get the result in physical domain. The results in the form of normal displacement, volume fraction, normal force stress, tangential force stress and tangential couple stress components have been obtained numerically and illustrated graphically.

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Various Response Functions in Lattice Domes Reliability Via Analytical Integration and Finite Element Method

Abstract

The main aim of this work is to verify an influence of the response function type in direct symbolic derivation of the probabilistic moments and coefficients of the structural state variables of axisymmetric spherical steel dome structures. The second purpose is to compare four various types of domes (ribbed, Schwedler, geodesic as well as diamatic) in the context of time-independent reliability assessment in the presence of an uncertainty in the structural steel Young modulus. We have considered various analytical response functions to approximate fundamental eigenfrequencies, critical load multiplier, global extreme vertical and horizontal displacements as well as local deformations. Particular values of the reliability indices calculated here can be of further assistance in the reliability assessment by comparing the minimal one with its counterpart given in the Eurocode depending upon the durability class, reference period and the given limit state type.

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Response of Non-Linear Shock Absorbers-Boundary Value Problem Analysis

Abstract

A nonlinear boundary value problem of two degrees-of-freedom (DOF) untuned vibration damper systems using nonlinear springs and dampers has been numerically studied. As far as untuned damper is concerned, sixteen different combinations of linear and nonlinear springs and dampers have been comprehensively analyzed taking into account transient terms. For different cases, a comparative study is made for response versus time for different spring and damper types at three important frequency ratios: one at r = 1, one at r > 1 and one at r <1. The response of the system is changed because of the spring and damper nonlinearities; the change is different for different cases. Accordingly, an initially stable absorber may become unstable with time and vice versa. The analysis also shows that higher nonlinearity terms make the system more unstable. Numerical simulation includes transient vibrations. Although problems are much more complicated compared to those for a tuned absorber, a comparison of the results generated by the present numerical scheme with the exact one shows quite a reasonable agreement

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Selected Problems to Support Decision Making in a Simulation Environment

-aisle warehouse , IIE Transactions 37, 2005. [13] Garcia, J., Berlanga, A., Molina, J. M., Casar, J. R., Optimization of airport ground operations integrating genetic and dynamic flow management algorithms, AI Communications, Vol. 18, No. 2, pp. 143-164, 2005. [14] Gotteland, J. B., Durand, N., Alliot, J. M., Page, E., Aircraft Ground Traffic Optimization , 4th International Air Traffic Management R&D Seminar (ATM ’01), Santa Fe, USA 2001. [15] Gotteland, J. B., Durand, N., Alliot, J. M., Handling CFMU slots in busy airports , 5th USA/Europe Air Traffic

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