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One of the most serious environmental problems in Poland is the pollution of the atmosphere. Due to the fact that the energy production mainly uses conventional sources of energy ? including predominantly hard coal, lignite and natural gas ? harmful products from the combustion of the raw materials get to the atmosphere. The air pollution from the combustion of hard coal is caused by many factors. They include the use of outdated furnaces, the inadequate use of furnaces and heating equipment, burning of low-qualit...

The aim of our proposals for soil sampling regarding mesofauna study in soils from greenhouses or polytunnels is motivated by the high soil heterogeneity and large variability of easy exchangeable soil properties such as water content, soluble salts distribution especially under drip irrigation and local fertilization. The intensive technology for growing vegetables or flowers, high irrigation requirements and the high soil moisture favors, in short time the degradation of morphological, physical, chemical propert...

The proportional-integral-differential (PID) law is often used to control the induction heating process. Mathematical modeling of induction heating in a three-dimensional formulation is associated with high costs of machine time to solve the electromagnetic field equations. The need to recalculate the heat dissipation field due to changing the power of the inductors at a small sampling period of PID controller leads to an excessive amount of calculations. Two methods of calculation of temperature fields of inducti...

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...

Soil animals by their size are usually subdivided into 5 groups: nano-, micro-, meso-, macrofauna and megafauna. Mesofauna is the most numerous part of soil animals. The mesofauna is represented by mokritsa, enchytraeids, insects, centipedes, spiders, mollusks, etc. Soil animals occupy, basically, the upper horizons (up to 20-40 cm deep), in dry areas only certain species penetrate to a depth of several meters. Mesofauna, along with other soil organisms, can be used as a bioindicator. In addition to the high abund...

The geographic information system is a widely used IT tool to support the management process in the field of geographic information. It is widely used in geodesy, cartography, construction and many other areas. It is used more and more frequently for spatial analyzes, the purpose of which is to determine the impact of various factors on the state of the environment or broadly understood security. Due to its versatility and the increasing availability the attempts are being made to apply this system in new areas li...

Underground hard coal exploitation is accompanied by a series of natural hazards. Their number and intensity increase along with the growing depth of exploitation. Amongst the most dangerous hazards in the mining industry, one can distinguish the following: methane hazards, seismic hazards (including the rock-burst hazard) and coal dust explosion hazards. They are a common issue in Polish coal mines, thereby making it necessary for coal mines to identify the level of these hazards. It can also be assumed that ther...

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...

The quality of the operation of broadband wireless computer networks is largely determined by the mechanism of an ordered centralized poll of terminal stations, called polling. The models of polling systems adequately describe the operation of broadband wireless networks under the control of Wi-Fi and Wi-MAX protocols with a centralized coordination function (PCF). Despite the complexity and high cost, the equipment supporting centralized management most effectively uses the most valuable resources of a broadband ...

The article presents a way of identifying and modeling sound features in an urbanized environment. The subject of article is focused on the problem of noise pollution modeling coming from moving technical objects, i.e. vehicles that are potential sources of noise. In this case, the vehicles are treated as multi-source acoustic energy emission objects. The proposed approach assumes the occurrence of variable relations in the system: source-path propagation-receiver. In the presented method the information carrier i...

The enterprises of the power industry worked by coal are one of the active sources of environmental pollution with heavy metals. The Novocherkassk State Power Station is the biggest power industry in the South of Russia. The atmospheric emissions contain heavy metals including Cu. Copper in soils exists in different chemical forms or types of binding. In environmental studies, the determination of these forms gives more information on trace metal mobility, as well as on their availability and toxicity, in comparis...

Fuel and energy management and related energy security are key issues for every country. The selection of energy sources used by individual countries depends on the possessed resources of energy raw materials, the economic position and, to an increasing extent, the approach to environmental protection. These factors shape the so-called energy policy of a given country. In the case of Poland, this policy is based on conventional energy sources. The main energy resource of the country is hard coal, the extraction of...

Facilities and technical systems used in coal mines have limited durability. This is the result of very difficult conditions in which they are used. In particular it applies to environmental conditions and not entirely predictable load states of these facilities. Mining machines and devices are also exposed to various types of hazards, which in many cases significantly reduce their durability. For this reason, it is very important to properly use them and supervise and monitor their work. In this respect, huge res...

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...

The machines used in hard coal mining must exhibit very good technical, safety and reliability parameters. These parameters determine their efficiency, operational safety and effectiveness of the entire production process. The last several decades have seen increased mechanisation of the mining process. Increasingly more cutting-edge and efficient machines have been used for this purpose. Attempts have also been made to partially or fully automate the process of mining. The concept of an ?intelligent? mine has com...