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This paper deals with stochastic Job-shop with random processing times where the objective is to find schedules robust enough in order to minimize the total completion time of all the operations. The problem is handled by use of a multi-start metaheuristic and a simulation software. At each iteration of the metaheuristic the best deterministic schedule is tested using the SIMAN simulation language;...
A back stepping controller is proposed for the trajectory tracking of an autonomous helicopter. The controller possess the capability of active disturbance rejection by using extended state observer to estimate the disturbances, such as wind gust. Simulation results based on the nonlinear helicopter model demonstrate the robustness of the controller.
Considering the demand on energy savings in future wireless networks, consumptions on cooperative links between different base stations becomes more and more critical with the rapid development of wireless communication systems. Coordinated Multi-Point Transmission/Reception (CoMP) gradually becomes popular due to the demand of higher transmission rate and more reliable Quality of Service (QoS), but...
Image quality enhancement is a crucial requirement in many applications of digital image and video processing. Removing artifacts which are suffered from image compression will lose simultaneously image texture components. This paper combines Beltrami method and the window derivative to construct the texture map in an attempt to preserve image details during filtering artifacts. Texture map enhancement...
The traditional CRT based algorithms have been proposed to solve the problem of range estimation with multi-frequency phase unwrapping, where the wavelengths of the multi-frequency signals should to be pair-wisely co-prime after they are divided by their greatest common divisor (GCD). To get a robust reconstruction result, the upper bound of the remainder errors should be smaller than a quarter of...
Aiming at classic Mean Shift based on tracking algorithm can not track target when the speed changed, the paper proposed an improved algorithm based on corrected background weighted histogram(CBWH), the algorithm used two iterations on target, first time used mean shift to iterate and calculated the similarity coefficient, second iteration used twice the current frame center minus the previous frame...
In this paper, a novel guidance scheme is presented for UAVs using the Integrated Guidance and Control (IGC) framework. The proposed guidance scheme is derived using H∞ Loop Shaping Design Procedure (LSDP). To recover from an initial cross track error, the proposed guidance algorithm produces such aileron commands that ensure the roll maneuvers without saturating the roll angle. The shaping of the...
The mathematical model of small fixed-wing UAV is difficult to determine precisely, especially for low-cost UAVs due to the limitation of the body material. Control of small UAVs with model uncertainty is an open problem both in the control community and engineering field. Active disturbance rejection control (ADRC) proposed by Jingqing Han has been shown to be an effective tool in dealing with real...
In the following paper, L1 adaptive control theory is used to design a controller for longitudinal short-period aircraft pitch. This controller accounts for the uncertainties of the aircraft model and the lack of robustness of existing methods. The aircraft handling qualities of six groups of different flight cases were used to build this model, regarding the uncertainties of the aircraft model as...
This paper is concerned with congestion control for dynamic TCP/AQM networks with random delays. A robust congestion control algorithm is presented based on the H∞ approach, and the system performance is analyzed via linear matrix inequalities (LMIs). Simulation results illustrate the effectiveness of the proposed algorithm.
In this paper, a novel active queue management scheme is proposed to control the congestion in the networks using TCP/IP protocol for transport layer. Active queue management (AQM) is a complement protocol to TCP/IP which provides feedback to the TCP sources in order to perform close loop congestion control. We use the nonlinear model of TCP/AQM system and build our controller on this realistic model...
In the present paper, proper orthogonal decomposition (POD) method is employed to derive a lumped-parameter model for systems governed by two-dimensional (2- D) parabolic convection-diffusion (PCD) equation. The POD method employs singular value decomposition (SVD) to explore the content of a data set in order to identify the most and least variation to choose lower-order basis functions that provide...
A flatness based decentralized Active Disturbance Rejection Control (ADRC) approach is here proposed as a means to deal with the fully nonlinear, exogenously perturbed, version, of the four-tank benchmark process problem under non-minimum phase behavior for the traditionally chosen system outputs. The liquid level control task, related to the two lower tanks, is transformed into a corresponding, indirect,...
This paper presents a new degree distribution based on power law so that LT code can perform well. Here, we have simulated our proposed degree distribution and have compared this distribution with robust soliton, binomial, pareto and parabolic distributions. Simulation result shows that this proposed degree distribution outperforms compared to other distribution techniques in terms of message length...
The adaptive-robust control strategy, proposed in this paper, combines the advantages of robust and adaptive control, while minimizing the computational load. Usually, a lot of mathematical operations are necessary, which limit the real time applicability of such strategies. By developing a simple, yet useful rule, the number of operations needed to determine if a new controller is needed has been...
This paper presents a treatment of variable structure discrete systems. Firstly, in order to control nonlinear single-input single-output (SISO) systems, the first sliding mode controller using the classical surface is considered. Then, a robust discrete second order sliding mode controller is investigated to overcome the effect of the chattering phenomenon. The controllers designed using the above...
This paper describes a fundamental limitation of the implicit anti-aliasing filter in continuous-time feedback compensated sigma-delta modulators and a method to overcome it. This anti-aliasing filter can be used to relax an additionally required pre filtering stage. If a strong alias rejection is required, commonly used continuous-time feedback compensated sigma-delta modulators would need some pre-filtering...
In a co-operation between the Institute of Automatic Control at the Aachen University of Technology and the Dräger Medizintechnik GmbH, Lübeck, a well-known developer and manufacturer of respiration devices, a digital feedback control strategy for the pressure-based ventilation was developed. However, the achieved controller is not robust enough against parameter variations (e.g. different patients)...
In this paper, we propose a new error criteria for determining the optimal multi-channel model system. The error criteria is based on assuming that the probability density function of the resulted error signal is t-distributed with α degrees of freedom. A small weighting factor is assigned for large amplitude signal portion parts and large weighting factor is used for small amplitude signal portion...
This paper presents a simulation-based method for performing high dimensional sensitivity analysis in multi-criteria decision making problems. The method integrates multi-criteria decision analysis, Monte Carlo simulation, and optimization techniques to assess the sensitivity of criteria weights and performance values of alternatives. It determines a ranking probability matrix by simulating stochastic...
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