Řada strojní. 2018, roč. 64 / Mechanical Series. 2018, vol. 64
Permanent URI for this collectionhttp://hdl.handle.net/10084/133292
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Item type: Item , Evaluation of the Road Surface Quality Inside the Road Tunnel(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Nemec, Dušan; Pirník, Rastislav; Hruboš, MariánThe paper discusses a method for quantitative evaluation of the road surface based on processing of the cloud of 3D points. The points are measured by high-speed laser scanner mounted on the vehicle. Such approach allows to scan the road surface without the need to stop the traffic inside the tunnel. The obtained data are processed in offline mode. The processing algorithm evaluates the structure (texture) of the surface, which has the direct impact on the safety of the road transport.Item type: Item , Simulation of a two degrees of freedom controller with a liquid tank(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Sladká, KarlaThe article is dealing with the control of liquid tank system. For the process control, it is implemented two degrees of freedom controller. The system is simulated in Matlab and the results are compared with a control system with standard controller.Item type: Item , Boundary movement in static eulerian mesh(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Kováčik, MichalThis work is focused on a procedure to treat the boundary movement associated to fluid-structure interaction. In the beginning, the theory of the procedure is described. The procedure described here is an alternative to the deformation of the Eulerian mesh bounded by the solid phase. This alternative procedure is then applied to a specific one-dimensional problem, where results are visualized and discussed. Alas, the cons and pros of the method are considered as well as alternatives to improve the method.Item type: Item , Problems of low cost carriers in the market(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Kontriková, LenkaLow cost carriers are air carriers which offer air transport for significantly lower prices than traditional carriers thus making air transport accessible even to those groups of travellers for whom air transport was unaffordable in the past. Low cost carriers also cause the air travel to be more popular and wide-spread kind of transport. From the point of view of constantly increasing number of transported passengers the low cost carriers are becoming an interesting segment of business. Unfortunately, the influence of low cost carriers in the aviation market has its drawbacks as well. As an example of such a drawback can be used the effort to transfer as many cost categories as possible to other entities, which can subsequently experience economic troubles and are forced to operate with economic loss. The article focuses on the evaluation of the influence of low cost carriers in the Czech market.Item type: Item , Mathematical models of 2D plotter components(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Jurek, MartinThis paper deals with most common 2D plotter components and provide identification procedure and exact parameters needed for mathematical modelling. Since a lot of Open-Source CNC machines use the same components, this information can be used to build-upon and improve performance of millions of machines.Item type: Item , An integrated mathematical model of crew scheduling(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Graf, VojtěchIn conditions of air transport companies, the process of planning flight schedules is one of the most important processes each airline has to deal with. The flight schedule planning process consists of several consecutive plans. The first step of the planning process is defining which air routes will be operated, the decision is based on the business plan of the air transport company. Consequently, suitable airplanes have to be assigned to the individual air routes. And finally, on the basis of the pre-vious steps shifts of pilots can be planned, the shifts are usually planned one month in advance. However, with no respect to the created plan some unexpected disruptions of the flying staff, especially of the pilots, may happen in practice due to many reasons. In such cases the original plan has to be modified in order to react to the disruptions. The modifications can represent an optimisation problem – the air transport company has a set of the pilots and on the basis of their qualification and experience the company has to create new aircrews. The pilots can be found in different localities that are different from the airports of the planned flight departures. That means the newly planned aircrews are assigned to the individual flights with respect to costs associated with transportation of the aircrews to the airports of their departure. The problem can be solved by many approaches. One of the possible approaches is a heuristic approach which is based on sequential solving two linear mathematical models. The first model decides about the aircrews (matches the pilots with respect to their compatibility). The second model solves the assignment problem – the air-crews are matched with the individual flights. The article presents an integrated linear model which deals with both problems at the same time.Item type: Item , Tuning of PID Controllers for Linear Dynamic Systems Using “Brute Force and Visual” Method(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Závada, JiříFor PID controllers in control loops, which in practice still prevails, it is necessary to determine controller parameter values which assure sufficient quality and robustness of control. A lot of PID tuning methods is described and well established in daily use. They are often based either on behavior of closed control loop or on a mathematic model of the controlled plant (and its L-transfer function), which allow to determine controller parameters by direct calculation. With increasing computing power of HW and SW aids it could be beneficial to use a method for determining the optimal setting of PID controller by simulation of control loop behavior for various meaningful combinations of controller parameter values (state space search). Proposed method “brute force and visual” of PID controller tuning is based on repeated simulation of control process as a reaction to Heaviside step of desired value and disturbing value for varying parameters of controller’s P, I, D components. For discrete controller also impact of sampling period T was considered. For each of the individual simulation runs there is kept a diagram as an image file as well as the control optimality criterion value. After execution of all the simulation runs for parameter values from the considered searched state space the simulation outputs are sorted by value of the selected control optimality criterion. The parameters of the individual simulation which has scored best are used for setting of the real controller and evaluated in the real control loop. From the simulations available for wide combination of parameter values it is possible to estimate position of isles of stability and choose the PID controller values by an expert choice.Item type: Item , RFID Technology and Blockchain in Supply Chain(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Kubáč, LukášThe paper discusses the possibility of combining RFID and Blockchain technology to more effectively prevent counterfeiting of products or raw materials, and to solve problems related to production, logistics and storage. Linking these technologies can lead to better planning by increasing the transparency and traceability of industrial or logistical processes or such as efficient detection of critical chain sites.Item type: Item , Design of a Universal Assembly Machine Concept Using the Industry 4.0 Conception(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Kristel, Peter; Kebo, VladimírThe aim of the thesis is to present the concept of the assembly device, which is based on the equipment already implemented. The concept involves deploying collaborative robots to increase the efficiency of the assembly cycle. The primary goal is to use time that is used in conventional equipment only for handling device operations. Collaborative activity reduces worker downtime, and this timeframe is significant in terms of process.Item type: Item , Measuring of Mechanical Properties of Flexible Container Fabric(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Kováčik, MichalThis work is focused on measuring mechanical properties of a fabric used in flexible intermediate bulk containers. Firstly, the methods of measuring are analyzed and discussed. Then a method of measuring is chosen with the devices needed to accomplish it. The results of the actual experiment are presented in form of pictures and charts. At last conclusions of the measured data are presented.Item type: Item , Human Fatigue Estimate: Usage of Systems from Traffic in Buildings(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Kohout, Jan; Mareš, JanFatigue monitoring is nowadays domain in traffic and transportation (e.g. system for driver's sleepness monitoring in cars or in trains). People working in offices are affected by fatigue too, but there is no general system that is able to monitor it. The fatigue in offices can cause decreasing work productivity or security risks in the industry. This review article compares the advantages and disadvantages of approaches used in traffic (e.g. an eye-movement tracking, driver activity) in internal environment (in buildings) with focus on people that work in offices with a computer. Because of the greater possibility of movement, it can not be enough. People are in offices longer than in cars and this causes that they are more affected by the quality of the internal environment. It should be useful to include this information in a system for fatigue monitoring. It can result in a system that is able to quantify fatigue level from both biological and environment variables.Item type: Item , Slip and Adhesion in a Railway Wheelset Simulink Model Proposed for Detection Driving Conditions Via Neural Networks(Vysoká škola báňská - Technická univerzita Ostrava, 2018) Dybala, Vojtěch; Libenský, Martin; Šulc, Bohumil; Oswald, CyrilConstantly enlarging operation of locomotives with a very high tractive power in modern railway transport has caused problems with optimal supplying torque from motor to wheel-sets. Losses emerging with inadequate torque values lead to wheel slipping connected with excessive wear and limited acceleration. In models simulating dynamics of torque transmission from the drive units to wheels, the most important are the submodel of the drive and the submodel of balance between traction forces and drive resistances. Some issues of this field studied within a PhD program and SGS (CTU Students Grant Competition) has been focused on increasing quality of these submodels. This contribution is aimed at an innovated part in the existing Simulink model utilizing new data sources and modeling techniques. This improvement supports application of operating point detection methods based on machine learning techniques. New control facilities provided with pulse-width modulated frequency control of the asynchronous motor will be used for automatic submission of optimal operating points. The idea of utilization of via simulation obtained data is an on-line training of polynomial neural unit as an approximation of current driving conditions.