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Ground station scheduling problem arises in spacecraft operations and aims to allocate ground stations to spacecraft to make possible the communication between operations teams and spacecraft systems. This problem consists in computing an optimal planning of communications between satellites or spacecraft (SC) and operations teams of Ground Station (GS). The information transmitted in these communications...
In this paper, we evaluate the performance of WMN-GA system for different settings of number of mesh clients. We consider Weibull and Exponential distribution of mesh clients, which represent hotspot scenarios. The population size is considered 64 and the number of generation 400. For evaluation, we consider average size of giant component(Avg. SGC) and average number of covered mesh clients(Avg....
The typical Sky-Wave Radar receive array require extensive leveling of the terrain in front of antenna for low side-lobe performance. This results in significant costs and may bring environmental crises. Thus, a special sparse array system is commonly adopted in this situation, which is able to avoid engineering cost problem by deploying the array elements only in the relative flat terrain and discarding...
In this paper, pioneering Adaptive Neuro Fuzzy Inference System (ANFIS) which is trained with well known traditional Proportional, Integral and Derivative (PID) controller data for Half Car (HC) model is proposed to improve the travelling comfort. The travelling performance is generally assessed at the design stage in automobile industries by simulating the vehicle response to various road excitations...
The data placement strategy is an important issue in the scientific workflows which is devoted to reducing the data movements while placing datasets in a few data centers according to the data centers' storage capacity and the data dependency. The data placement is proved to be a NP hard problem, and several methods for this problem like K-means clustering algorithm are presented in the literatures...
Lifetime is a key issue in wireless sensor network (WSN) applications. An effective way to extend WSN lifetime is to partition the set of sensors into several covers and activate them alternately. More covers then lead to longer lifetime. Finding the maximum number of covers under full coverage constraint has been formulated as an NP-complete problem—the SET K-COVER problem. This study...
In this paper, we deal with the impact of the population size and number of generations on the performance of a dense WMN. The network is compound of 8 mesh routers and 96 mesh clients. We evaluate the performance considering giant component, number of covered users and the total execution time of GA. The simulation results show that the increase of the population size or the increase of the number...
Wireless Mesh Networks (WMNs) are important networking infrastructure for providing cost-efficient broadband wireless connectivity. Mesh router node placement is important to achieve network connectivity and coverage in such networks. In this paper, we deal with the effect of changes in population size and number of generations for node placement problem in WMNs. We consider two population sizes 8...
The so-called heuristics have been widely used in solving combinatorial optimization problems because they provide a simple but effective way to find an approximate solution. These technologies are very useful for users who do not need the exact solution but who care very much about the response time. For every existing heuristic algorithm has its pros and cons, a hyper-heuristic clustering algorithm...
Radio resource management in multi-user LTE networks is considered in this paper. Subject to a transmission power constraint, genetic algorithm is firstly investigated to optimize the system transmission rate. However, result shows genetic algorithm has the flaws of slow convergence rate and cannot reach to the theoretical maximum transmission rate. Aiming at this point, ant colony algorithm (ACA)...
The Ground Station Scheduling is one of the most important problems in the field of Satellite-Scheduling. This problem consists in planning feasible planning of communications between satellites or spacecraft (SC) and operations teams of Ground Station (GS). The information received in these communications is usually basic information such as telemetry, tracking information or tasks to perform, so...
In this work, a novel point stabilization control strategy for mobile robots which moves on uneven surface is presented. Firstly, sliding mode method is adopted to extend the nonlinear kenimatic control law to dynamic system, so that the robot is driven by torques. Then, to solve the speed and torque jump problem, the neural dynamics model is integrated into the presented controller. In addition,...
Recently there has been a growing interest in mission operations scheduling problem. The problem, in a variety of formulations, arises in management of satellite/space missions requiring efficient allocation of user requests to make possible the communication between operations teams and spacecraft systems. Not only large space agencies, such as ESA (European Space Agency) and NASA, but also smaller...
Wireless Mesh Networks (WMNs) distinguish for they low cost nature that makes them very attractive for providing wireless Internet connectivity. Such infrastructures can be used to deploy community networks, metropolitan area networks, municipal and corporative networks, and to support applications for urban areas, medical, transport and surveillance systems. The main issues in WMNs are achievement...
With the emergence of several new networking paradigms, optimization modeling and resolution turns out to be crucial to achieve optimized performance networks. One such networking paradigm that requires resolution of optimization problems is Wireless Mesh Networks (WMNs). In this paper, we deal with the effects of population size in GA for node placement problem in WMNs. We evaluate the performance...
Unlike the traditional approaches that utilize original data patterns to construct the fuzzy model, an approach exploiting both data transformation techniques and heuristic method is proposed to simplify the modeling procedures. For the transferred data, firstly, the initial value of fuzzy if-then rules with nonfuzzy singletons (i.e., real numbers) in the consequent parts is generated by the heuristic...
This paper presents an implementation of the Chemical Reaction Optimization (CRO) algorithm to solve the optimal power flow (OPF) problem in power systems with the objective of minimizing generation costs. Multiple constraints, such as the balance of the power, bus voltage magnitude limits, transmission line flow limits, transformer tap settings, etc., are considered. We adapt the CRO framework to...
In this paper, we deal with a preventive maintenance (PM) scheduling and spare parts problems for a rolling stock system. We determine the optimal PM interval and the optimal number of spare parts for components in the rolling stock system to minimize the system life cycle cost during satisfying the system target availability. The system availability and system life cycle cost are estimated by simulation...
Emission reduction, this expression is one of the most frequently used in the last years. Its meaning is known very well for the ordinary people, ordinary in the sense of being not associated with the automotive industry. One of the strategies for NOx emissions reduction in personal vehicles with combustion engine is the Selective Catalytic Reduction System. The critical issue of such systems can...
This paper treats a tuning of PID controllers method using Multi-objective Differential Evolution. The objective was to apply the differential evolution algorithm in the aim of tuning the optimum solution of the PID controllers (Kp, Ki and Kd) by minimizing the multi-objective function. The potential of using Multi-objective Differential Evolution is to identify Pareto-optimal solution. A classic...
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