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The Application of Ant Algorithm in the Assignment Problem of Aircrafts to Stops Points on the Apron

Abstract

The article refers to the problem of assigning the aircrafts to stops points on the apron. The aim of this paper is to develop the algorithm, which will be used to this assignment. The assignment problem of aircrafts to stops points is the complex decision problems, which refer to the problems of designating the minimal path in the graph. The assignment model was described, i.e. decision variables, constraints and the criterion function. Decision variables take the binary form and determine the connections between the elements of infrastructure of the apron, i.e. touchdown points, intermediate points and stop points. Constraints take into account the number of aircrafts in the given period, the number of unoccupied stop points. The criterion function determines the minimum driving time of the aircraft on the apron. In order to designate the routes in international transport the heuristic algorithm, i.e. ant algorithm was developed. The steps of building this algorithm were presented. This algorithm was verified in the C# programming language. The results generating by the presented algorithm were compared with the results generating by the random algorithm.

Open access
Application of Drones in Protection of State Border

Abstract

An unmanned aerial vehicle is a flying apparatus that does not require a crewmember on board to complete a task. Its piloting is done by means of indirect control. UAVs also have the ability to perform autonomous flight on a pre-programmed flight path. The purpose of the study was to use the unmanned aircraft “Fly Eye” by WB Electronic used by the Border Guard to patrol the state border in 103 TRA zone on the section of the Republic of Poland with the Kaliningrad District of the Russian Federation. The TRA zones constitute a specially designated area for the use of the Border Guard and the army, in order to carry out flights there beyond the scope of the pattern for training purposes and to patrol the state border. The article also contains information of the Border Guard formation and the characteristics of the unmanned aerial vehicle “FlyEye”. In order to ensure the safety of the UAV flight, the test was carried out in the TRA zone, which is used for special use for the Border Guard formation and the army.

Open access
The Application of Genetic Algorithm in the Assignment Problems in the Transportation Company

Abstract

The article presents the problem of the task assignment of the vehicles for the transportation company, which deals with the transport of the cargo in the full truckload system. The presented problem is a complex decision making issue which has not been analysed in the literature before. There must be passed through two stages in order to solve the task assignment problem of the vehicles for the transportation company. The first stage is to designate the tasks, the other one is to determine the number of the vehicles that perform these tasks. The task in the analysed problem is defined as transporting the cargo from the suppliers to the recipients. The transportation routes of the cargo must be determined. In order to solve the task assignment problem of the vehicles, the genetic algorithm has been developed. The construction stages of this algorithm are presented. The algorithm has been developed to solve the multi-criteria decision problem. What is more, the algorithm is verified by the use of the real input data.

Open access
Application of Multi-Criteria Optimization to Choose Variants of Hardware Architecture for the SWPL-1 Helmet-Mounted Display System

Abstract

The paper presents the structure and basic properties of the SWPL-1 helmet-mounted flight parameter display system, constructed for the Mi-17 helicopter with analogue systems and on-board instruments. It describes the basic components of the SWPL-1 system and on board components cooperating with the SWPL-1 system necessary to ensure the imaging system’s operation (including the ADU-3200 central unit for aerodynamic data and the GPS-155XL satellite signals receiver). It presents the architecture, the principle of operation, and the main constituents of the SWPL-1 helmet-mounted flight parameter system, as well as the standards of data transmission used in digital communication between the SWPL-1 system and on-board systems (installed on the Mi-17 helicopter). It describes the scope and manner of pilot and navigation data presentation as well as control of drive unit operation parameters in detail. It presents selected optimization methods for tasks executed in the helmet mounted system’s life cycle. The particular stages of the life cycle were described in detail, from the earliest stages of needs identification, through the analytic and conceptual phase, then the implementation stage, and ending with the operation stage. It introduces tasks for optimization and related methods into the process of creating the new system at every stage of its implementation. It presents one of the methods of multi-criteria optimization based on the experts’ assessment of choice of a variant of the helmet-mounted flight parameter display system’s hardware architecture in detail.

Open access
Application of Similarity Method of Distance Courses Describing the Elements Content in Typical Cement Concrete

Abstract

The article concerns the use of similarity analysis of distance course in the internal area of cement concrete intended for airfield pavements. Research procedure was presented and the obtained laboratory tests results were discussed. The contents of diversified elements in four zones (cement matrix, contact area between air pores and cement matrix, contact area between fine aggregate and cement matrix and contact area between coarse aggregate and cement matrix) were specified by using scanning electron microscope. Based on the results obtained diagrams similarity of the analysed of areas in the concretes were prepared. The purpose of this article has been the assessment of an opportunity to apply the analysis of similarity of distance courses with respect to cement concrete intended for airfield pavements. The scope of article consisted of two stages. The analysis included cement concretes intended for airfield pavements, in compliance with requirements. The thermal analysis method was used; the selected concrete components were determined by means of quantitative method. The occurrence of crystalline stages was determined using X-ray diffraction method. Internal structure of concrete composite was assessed with the scanning electron microscope.

Open access
The Car Fleet Management Model with Including Expectations of the Users

Abstract

The paper presents a certain approach to fleet management in the company, taking into account the mobility of employees and the selection of vehicles for tasks. The main objective is to indicate the factors that significantly affect the proper selection of vehicles for the task, as well as concurrently meeting recipients' needs. The general model for fleet management was presented, taking into account not only the mobility of employees but also the method of obtaining funds for the replacement of greener cars. The current approach is based on the car purchase model in the form of credit, low-purchase leasing, and supervision over the use process and operating costs by the company's internal resources. The problem solved in the article concerns the analysis of entrusting fleet management to specialized Car Fleet Management (CFM) companies. It was pointed out that in this calculation model, CFM companies have to take into account many variables related to vehicle selection and mobility of employees in order to perform tasks. In this article, particular attention has been paid to the areas that CFM analyses when choosing a vehicle for a given company.

Open access
CFD Simulations as a Support of Experimental Research in a Rapid Compression Expansion Machine Facility

Abstract

The main aim of this study to reproduce methane combustion experiment conducted in a rapid compression-expansion machine using AVL FIRETM software in order to shed more light on the in-cylinder processes. The piston movement profile, initial and boundary conditions as well as the geometry of the combustion chamber with a prechamber were the same as in the experiment. Authors by means of numerical simulations attempted to reproduce pressure profile from the experiment. As the first step, dead volume was tuned to match pressures for a non-combustion (air-only) case. Obtained pressure profile in air compression simulations was slightly wider (prolonged occurrence of high pressure) than in the experiment, what at this stage was assumed to have negligible significance. The next step after adjusting dead volume included combustion simulations. In the real test facility, the process of filling the combustion chamber with air-fuel mixture takes 15 s. In order to shorten computational time first combustion simulations were started after the chamber is already filled assuming uniform mixture. These simulations resulted in more than two times higher maximum pressure than recorded in experiments. It was concluded that turbulence decays quickly after filling process, what was also confirmed by next combustion simulations preceded by the filling process. Then the maximum pressure was significantly decreased but still it was higher than in the experiments. Based on the obtained results it was assumed that the discrepancy noticed in air cases is further increased when combustion is included. Moreover, the obtained results indicated that pre-combustion turbulence level is very low and suggested that either piston profile movement is not correct or there is high-pressure leak in the test facility.

Open access
CFD Tests of the Exhaust System of a Sports Motorcycle

Abstract

The content of this article describes the area of the operation of speedway racing motorcycles, it reflects the specific use, and thus, the special requirements placed on the internal combustion engines used there. Then, a research tool is presented in the form of Computational Fluid Dynamics methods. The article presents basic equations as a base for software, and emphasizes the essence and necessity of adequate selection of turbulence models. Presentation of the work tool is crowned with a brief description of the application in the form of Ansys numerical analysis software and a specific place and possibilities of its application. The practical part describes the work carried out during the tests of a GM 500 type combustion engine and attempts to compare two types of exhaust systems whose advantages and disadvantages in analytical calculations are difficult to determine, whereas CFD tests accurately represent pressure fields, velocities and the most important parameter in the form of resistance of the exhaust system. The article is crowned with the results of tests enabling determination and selection of the exhaust system with lower flow resistance and recommendations adjusting the exhaust system to a specific engine.

Open access
Characteristic Features of the Process of Growth in the Mileage of Hybrid Vehicles

Abstract

For a few years, the sales of motor vehicles with hybrid drive systems (referred to as “hybrid vehicles” or “HVs”) have been rapidly growing. However, there is a lack of information about the intensity of operation of vehicles classified in this category, which is completely new. A calculation procedure has been presented that enabled evaluation of the HV mileage growth rate. An analysis of this rate provides grounds for forecasting the changes that are likely to take place in the fleet of motor vehicles, such as the progress in the process of replacement of conventional vehicles with vehicles with alternative drive systems, and this may be a basis for predicting the reduction in fuel consumption and exhaust emissions. Models of the HV mileage growth process have been defined for three different countries. They indicate high mileage growth rates in the initial period of vehicle operation, e.g. until the fourth year of operation of the Auris H cars. The highest mileage growth rates in this period were observed in the Netherlands and Poland. In Germany, this rate was lower by 41%. Significant differences in the intensity of vehicle operation have been observed between the behaviour of HV owners in the countries under analysis. A considerable drop in the annual HV mileage as early as in the fifth and sixth year of vehicle operation is an alarming signal.

Open access
Comparative Analysis of the Fuel Consumption of Vehicles Equipped with Various Types of Automatic Transmissions

Abstract

The growing number of vehicles moving on Polish roads equipped with various types of automatic transmissions prompted the authors of this publication to carry out research to assess the impact of the use of this type of transmission on the fuel consumption of these vehicles. The presented article presents a comparative analysis of the fuel consumption of vehicles of different manufacturers equipped with automatic transmissions moving in specially prepared driving cycles for research purposes. In the developed driving cycle, the vehicle speed was gradually increased every 10 km/h, maintaining each speed for a period of at least 30 seconds in order to stabilize the measurement results. The tests were carried out for various load stages of the drive system. Load differentiation was made by simulating driving in the prepared cycle for simulated different slopes of the road. The tests were carried out on the MAHA MSR500 chassis dynamometer, and the obtained results for the vehicle moving in automatic mode, where the transmission controller selected the gear ratio according to the programmed algorithm, were compared with the vehicle's fuel consumption for the vehicle gear selected by the driver in the driving cycle. The control software used to test the chassis dynamometer allows taking into account the increasing resistance of traffic along with the increase of vehicle speed, which greatly approximates the simulated conditions in the laboratory to the conditions on the road. The main purpose of this publication is to check whether using automatic transmissions or other control algorithm of these gears can achieve a reduction in fuel consumption.

Open access