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The pressure transducer installed in the hydraulic system play an important role for the correct work of the powered roof support. Currently, in the free market economy there are many manufacturers offering a wide range of such products, however, it is often difficult to find a solution that would meet specific requirements, for example when selecting a pressure transducer for a powered roof support. It is difficult to find an ideal transducer that would meet all the requirements for the correct operation of the s...

One of the most popular systems of simulation - GPSS World provides users (1) software tools to interact with the system in the process of simulation research and (2) software tools, realizing immediately the implementation of the model (including: syntax analyzer interpreter model, clock modeling, management of the list of events and more.). Until a few years ago the programs in the first group only automated a part of research itself, namely the creation of a text model and conduct experiments with it. In the ab...

A wireless system of continuous monitoring of pressure in a leg mounted in a powered roof support was designed in order to ensure the continuity of longwall coal mining process. Wireless multi-channel signal transmission in the longwall was applied for the first time. The extension of the power cell enabled maintenance-free use of the system and ensured comprehensive control of the support. The presented system monitors the pressure value in the spaces under the leg?s piston mounted in a powered roof support as we...

Additive manufacturing is used in multiple industries to create prototypes, visual models and objects with complex geometries. Being able to fabricate an object layer by layer, additive manufacturing offers the possibility to create objects with embedded, non-assembly joints. With Fused Deposition Modeling (FDM), one of the most common and accessible 3D printing processes, minimizing joint clearance for models with non-assembly joints presents a challenge, especially in the case of consumer-grade desktop machines....

Major efforts are directed worldwide in order to establish proper strategies for the preservation of soil quality, its protection and sustainable use by precision farming techniques. Since the in-depth distribution of soil moisture represent valuable information for farmers, electric and electromagnetic techniques were employed for its investigation. Electrical resistivity tomography (ERT) with small electrode space interval was utilized for illustrating sectors of vertical water penetration and horizontal sectors...

The Fourier Transform Infrared (FT-IR) spectroscopy is one of the suitable experimental tools for analysis of urinary calculi constituents. However, interpretation of infrared spectra for quantifying urinary calculus constituents in mixtures is difficult, requiring expert knowledge by trained technicians. The development of automated methods for determining the composition of uroconcrements is very important since it can facilitate the determination of the factors which influence the occurrence of calculi in urina...

Work safety in hard coal mines is implemented based on Geological and Mining Law. It imposes an obligation on the entrepreneur to identify hazards related to activities of the mine and to undertake actions aimed at preventing and removing these threats and hazards. The owner is required to assess the risk and propose solutions necessary to minimize it. These activities must cover all activities performed during the production process and the operation of all types of equipment, including mining machines. The most ...

An electrohydraulic control system as a part of powered roof support is required to be equipped with a safety valve. The aim of the valve is to protect the roof support against overloads that may damage hydraulic legs, and subsequently lead to loss of stability of the whole support unit. In order to select optimal operating parameters of the safety valve it is necessary to carry out tests in conditions similar to those in the mine. The tests should reflect the actual load condition of the support as much as possib...