Tag Archives: frequency

987–992 J. Hart and J. Bradna
Suitability of 2.4 GHz and 5 GHz wireless communications in production processes
Abstract |

Suitability of 2.4 GHz and 5 GHz wireless communications in production processes

J. Hart* and J. Bradna

Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 00 Prague, Czech Republic
*Correspondence: janhart77@gmail.com

Abstract:

Today, it is increasingly modern to use wireless transmissions in production. It is possible to send information messages, control messages and it is often possible to access the technologies as IoT (the Internet of Things). The aim of this work was to find out which of the selected Wi-Fi frequencies is more suitable for use in syrup processing equipment. The evaluation was performed on the basis of attenuation and download speed at each frequency (2.4 GHz and 5 GHz bandwidth). These frequencies have been chosen due to their massive deployment for wi-fi networks that currently dominate wireless communications. Measurements were made downloading files on different frequency bands. Mean and maximum data throughput and signal strengths were also measured. By measuring, it has been found that when using 2.4 GHz wireless Wi-Fi technology, you can very often encounter strong interference effects. Despite the theoretically worse 5 GHz frequency spread, you can achieve up to 30% better data throughput on average. The results show the suitability of 2.4 and 5 GHz Wi-Fi technology. The main finding is that, despite the worse frequency spread of 5 GHz, it is more appropriate. Not only due to speed but also in the future due to better transmission capacities and future channel expansion.

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711–724 V. Bulgakov, V. Adamchuk, V. Gorobey and J. Olt
Theory of the oscillations of a toothed disc opener during its movement across irregularities of the soil surface
Abstract |
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Theory of the oscillations of a toothed disc opener during its movement across irregularities of the soil surface

V. Bulgakov¹, V. Adamchuk², V. Gorobey² and J. Olt³*

¹National University of Life and Environmental Sciences of Ukraine, 15, Heroyiv Oborony Str., UK 03041 Kyiv, Ukraine
²National Scientific Centre, Institute for Agricultural Engineering and Electrification, 11, Vokzalna Str., Glevaкha-1, Vasylkiv District, UK 08631 Kiev Region, Ukraine
³Estonian University of Life Sciences, Kreutzwaldi 56, EE51014 Tartu, Estonia
*Correspondence: jyri.olt@emu.ee

Abstract:

 The paper presents the main provisions of the new theory of oscillations of the versatile combined opener assembly of the breeding seed drill with a spring-suspended furrow opening toothed disc in the vertical longitudinal plane during its movement across irregularities of the soil surface. Basing on the improved design of the opener assembly, an equivalent schematic model has been developed, which takes into account the forces applied to the structural components of the opener, forces in the springs as well as the reaction of the soil acting on the toothed disc, the hoe-type seed conductor and the packing wheel. The system of differential equations has been set up, which describes the movement of the opener across irregularities of the soil surface depending on the opener’s design parameters and the kinematic modes of performing the drilling work process. The derived mathematical model makes it possible to determine the amplitudes and frequencies of the translational oscillations of the device in order to assess their impact on the drilling work process. The developed theory provides also tools for the assessment and lowering of the energy characteristics of the versatile breeding seed drill related to the oscillating movements of its openers in soil.

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