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Number of results: 56
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Abstract

The assessment of a rock’s behaviour around excavations and the effectiveness of its reinforcement in underground ore mines is dependent on the performance of the rock-bolt and rock-mass interaction, which can be estimated on the basis of appropriately designed measurements. Based on the background of various measurements solutions described in the literature, concerning rock bolt monitoring methods, the authors proposed a new, original device for mass measurements in mine conditions. After examining the advantages and disadvantages of existing constructions, the article presents the essence, principle of operation and method of measuring anchor load in an underground excavation with the a instrument, indicator WK-2/8. The prototype has been carefully researched and successfully tested in a full-scale laboratory environment. This instrument, also referred to as a load indicator or force pad, does not require electrical power and allows for relatively accurate (with a resolution of 10-14kN, up to about 90kN loading capacity) and a remote reading of the axle loading of the anchor (AGH patent) by any person present in the specified area. The device can be installed in mining excavations under loading conditions. The relatively low cost of a measuring instrument, practically used as an additional washer, as well as an easy assembly method, makes it universally applicable in mines where anchoring is used as a means of strengthening the rock.
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Abstract

The utilization of mining waste is an important problem in Poland and Ukraine. The article presents one of the variants of waste mining in the quarry in Płaza. An analysis of the resource base of the deposit and their location at the area of Płaza deposit is carried out. The Płaza deposit is located in the western part of the Małopolskie province, in the entire Chrzanów commune. The Płaza deposit is constructed of Middle Triassic carbonates represented by the limestone-dolomite Olkusz Formation and the limestone-marlized Gogolin Formation. The deposit series lies on the dolomites of Röt age (Lower Triassic – Olenekian). The most valuable raw material was the pure limestone from the lower part of the Olkusz Formation, now almost completely exploited. The article presents the current state of mineable reserves of the deposit and their quality (chemical and physical characteristics). Moreover the article shows potential consumers of raw material and the possibility of extending the life of the mine work. According to the results of the environmental monitoring the ground and hydrogeological conditions were evaluated, the results of which allowed a more efficient use of the existing quarry area for mining waste disposal to be proposed. The paper presents a conceptual waste transport scheme, planned distribution and compaction of wastes belonging to the first, second and third group and then a surface reclamation. In view of the absence of similar decisions analogs, the consideration of the open-pit as a one solid geomechanical system functioning under the conditions of uncertainty is suggested. In order to examine the dynamics of the waste compaction process, some measures are foreseen to constantly observe their subsidence. The proposed measures for the synchronous disposal of mining waste in the worked-out area of the open-pit and the simultaneous mining operation in the quarry will allow the life cycle of the open-pit to be prolonged for 15–20 years.
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Abstract

A mine cannot function without monitoring systems: environmental, basic mining machinery and equipment. The exploitation of ore in the mine depends heavily on properly functioning machines and mining equipment, and acceptable for the miner technical environmental conditions occurring in underground excavations. The monitoring systems of the technical environment in underground mines are primarily telemetry and gasometry systems. The first part of the article shows the typical structure of gasometry systems operating in the Polish underground mines. The existing provisions include the so-called security systems of the mining plant. The article presents a quantitative summary of the telephone exchange types and count of main telecommunication lines operating in these systems. Monitoring systems of machines and mining equipment are an essential element of the effec-tive management of the mine, because they affect the safe operation and increase time of effi-ciency equipment. The second part of the article shows selected monitoring systems of mining machinery and equipment currently used in the dispatcher rooms of mines. Attention was paid to the monitoring systems, which are only software tools as well as those in which additionally use dedicated IT solutions for these systems, hardware and measuring tools. The table shows the types of monitoring systems and technological configurations used in underground mines, preferred for them.
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Abstract

In the breeding season 1988/89, within the region of SSSI No. 8, nesting of 12 species of birds was observed. The highest number of nests — 24430 — belonged to three species of pygoscelid penguins; 77.1% were the Adelie penguin. Relatively high fluctuations in the number of penguins in some rookeries in particular breeding seasons were confirmed. During regular countings of mammals' in 1988 the presence of 5 species of Pinnipedia was noted, of which the southern elephant seal was most numerous in the summer season, whereas crabeater seal — in winter. In the region of SSSI No. 8, breeding of southern elephant seal and Weddell seal was observed. Fluctuations in the number of seals in this region in the period 1977—1988 were insignificant.
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Abstract

In 1989/90, in the region of SSSI 8 situated on King George Island 21 bird species were observed, 12 species were breeding. Dominants were 3 Pygoscelis species (19229 pairs). Five species of pinnipedians were noticed. Mirounga leonina was most abundant in January (623 individuals), Arctocephalus gazella — in February and March (890 individuals), Hydrurga leptonyx in October (39 individuals). The abundance of Leptonychotes weddelli was low and rather stable. As a result of mild winter during the study period such birds as Sterna vittata and Pygoscelis adeliae stayed near their breeding places. The scarcity of Lobodon carcinophagus was probably also a result of this mild winter.
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Abstract

Since the 1970s, the Legnica-Głogów Copper District has an area of intensive mining of copper. Mining activities resulted in the appearance of induced seismic activity. This situation caused the necessity of setting an underground seismological network. In the mid-1990s, due to the great damage of objects on the surface caused by the ground vibrations due to mining tremors, a surface strong motion seismic network equipped with accelerometers was created. They monitor the vibration levels of both the land and the buildings themselves. This contributed to a better knowledge of the nature of ground vibration and the resistance of objects. In recent years, anthropogenic threats, which include seismicity induced by mining activities, are arousing more and more interest. To be able to develop test methods for seismic source physics, the analysis of the impact of vibrations on the surface and the seismic hazard, network measurement should also be developed and modernized. In the years 2014–2015, the IS-EPOS “Digital research space of induced seismicity for EPOS purposes” project, extended the LUMINEOS modern seismological network presently consisting of 15 seismometers and 10 accelerometers, with the possibility of additional further expansion. The data obtained from the LUMINEOS network complements the existing underground mining network and surface strong motion network. This allows for an advanced seismic analysis.
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Abstract

The paper presents the results of seven-year survey of Antarctic seals along the western shore of Admiralty Bay, King George Island, South Shetland Islands. Five species were monitored during seven of the eight years, between 1988-95, excluding 1993. Numbers of elephant seals and Antarctic fur seals showed strong annual cycles, fur seals with two seasonal peaks. These of the other three species were more irregular. Fewer Weddell seals were seen in 1994 and 1995 then during the period 1988-92; with this exception, no overall trend in numbers was apparent during the period 1988-95.
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Abstract

Geomechnical model testing has been widely applied as a kind of research technique in underground engineering problems. However, during the practical application process, due to the influence of many factors, the desired results cannot be obtained. In order to solve this problem, based on the measurement requirements of the model test, combined with FBG(Fiber Bragg Grating) sensor technology and traditional measurement methods, an FBG monitoring system, Micro-multi-point displacement test system, resistance strain test system and surrounding rock pressure monitoring system are developed. Applying the systems to a model test of the tunnel construction process, the displacement in advance laws of tunnel face, radial displacement distribution laws and surrounding rock pressure laws are obtained. Test results show that a multivariate information monitoring system has the advantage of high precision, stability and strong anti-jamming capability. It lays a solid foundation for the real-time data monitoring of the tunnel construction process model test.
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Abstract

Lower Carboniferous limestone has been extracted in the “Czatkowice” open-pit hill-slope quarry in southern Poland since 1947, for the needs of metallurgical and building industries, as well as farming. We can distinguish two aquifers in the Czatkowice area: the Quaternary porous aquifer and the Carboniferous fissure-porous one. Two vertical zones representing different hydrodynamic characteristics can be indentified in the Carboniferous formations. One is a weathering zone and the other one the zone of fissures and interbedding planes. Groundwater inflows into the quarry workings have been observed at the lowest mining level (+315 m above the sea level (asl)) for over 30 years. This study concerns two hypotheses of the sources of such inflows originating either from (a) the aeration zone or from (b) the saturation zone. Inflows into the quarry combine into one stream flowing gravitationally to the doline under the pile in the western part of the quarry. This situation does not cause a dewatering need. Extending eastward mining and lowering of the exploitation level lead to increased inflows.
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Abstract

This paper presents mathematical models enabling the calculation of the distribution and patterns of methane inflow to the air stream in a longwall seam being exploited and spoil on a longwall conveyor, taking into account the variability of shearer and conveyor operation and simulation results of the mining team using the Ventgraph-Plus software. In the research, an experiment was employed to observe changes in air parameters, in particular air velocity and methane concentration in the Cw-4 longwall area in seam 364/2 at KWK Budryk, during different phases of shearer operation in the area of the mining wall in methane hazard conditions. Presented is the method of data recording during the experiment which included records from the mine’s system for automatic gasometry, records from a wireless system of eight methane sensors installed in the end part of the longwall and additionally from nine methane anemometers located across the longwall on a grid. Synchronous data records obtained from these three independent sources were compared against the recording the operating condition of the shearer and haulage machines at the longwall in various phases of their operation (cleaning, cutting). The results of the multipoint system measurements made it possible to determine the volume of air and methane flow across the longwall working, and, consequently, to calculate the correction coefficients for determining the volume of air and methane from measurements of local air velocity and methane concentration. An attempt was made to determine the methane inflow from a unit of the longwall body area and the unit of spoil length on conveyors depending on the mining rate. The Cw-4 longwall ventilation was simulated using the data measured and calculated from measurements and the simulation results were discussed.
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Abstract

The emerging potentials in the electronics field, which facilitate the creation of complex projects with innovative functionalities, while maintaining low costs, are becoming even more appreciated by designers and engineers. In this manuscript, a telemetry system was designed and realized for monitoring main parameters of a racing vehicle. A STM32 Nucleo board acquires data from sensors installed on vehicle and transmits them to a base station. Acquired data are both stored on a SD card and wirelessly transmitted, for ensuring robustness/reliability of operation. The carried out tests confirm the truthfulness and compatibility of acquired data related to the vehicle parameters.
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Abstract

The need for effective and rational use of land, protection, and preservation of its qualitative state (as the agricultural land soil) is due to some negative details, namely, more than a third of the land is eroded, half of which are black soil in particular, which have an average level of nutrient supply, a lot of contaminated abandoned or overdented land. The acuteness of this problem, which has developed with regard to the protection and preservation of the land qualitative state, has become particularly relevant. The solution to this problem requires truly effective methods of influence. One of such methods is the surveillance of ecological and economic monitoring of land. The article analyzes the ecological and economic factors and factors influencing the monitoring and surveillance of land in Ukraine. Perspectives and objectives for improvements in land monitoring are highlighted. The paper discloses a theoretical synthesis and new approaches to solving the problem of environmental management, which can participate in the development of innovative economic and environmental factors of rational land use, which will contribute to enhancing the transition of Ukraine to the model of sustainable land use. The purpose of this work is a scientific analysis of the various organizational factors of monitoring and surveillance of agricultural land in relation to the current legislation in Ukraine.
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Abstract

Wireless Sensor Networks (WSNs) have existed for many years and had assimilated many interesting innovations. Advances in electronics, radio transceivers, processes of IC manufacturing and development of algorithms for operation of such networks now enable creating energy-efficient devices that provide practical levels of performance and a sufficient number of features. Environmental monitoring is one of the areas in which WSNs can be successfully used. At the same time this is a field where devices must either bring their own power reservoir, such as a battery, or scavenge energy locally from some natural phenomena. Improving the efficiency of energy harvesting methods reduces complexity of WSN structures. This survey is based on practical examples from the real world and provides an overview of state-of-the-art methods and techniques that are used to create energyefficient WSNs with energy harvesting.
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Abstract

The first step towards condition based maintenance of the milling plant is the implementation of online condition monitoring of the mill. The following paper presents and analyses methods of monitoring the key performance factors of a vertical spindle mill that is suited for implementation on older power stations, i.e. the quantity (mass flow rate) and quality (particle fineness) of the pulverised fuel produced by the mill. It is shown herein that the mill throughput can be monitored on-line using a simple mill energy balance that successfully predicts the coal throughput within 2.33% as compared to a calibrated coal feeder. A sensitivity analysis reveals that the coal moisture is a critical measurement for this method to be adopted as an on-line mass flow monitoring tool. A laser based particle size analyser tool was tested for use in the power plant environment as an online monitoring solution to measure pulverised fuel fineness. It was revealed that several factors around the set-up and operation of the instrument have an influence on the perceived results. Although the instrument showed good precision and repeatability of results, these factors must be taken into account in order to improve the accuracy of the reported results before the instrument can be commissioned as an on-line monitoring solution.
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Abstract

Spatial Disorder vs. Data Collection on Spatial Planning in Poland. The article deals with the issue of spatial disorder as a consequence of lack of information about spatial planning in local government administration units. An efficient monitoring system of spatial planning on the local level is indispensable for the effective implementation of public policies, development strategies and operational programmes. Lack of full knowledge of land use leads to irrational and unsustainable use of resources in municipalities. The activities of public statistics in the field of the quality of information on spatial management concern the quality and methods of obtaining data, while adjusting the information available to the needs of authorities responsible for spatial planning at all levels.
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Abstract

Trichloroethene (TCE) and tetrachloroethene (PCE) are chemical compounds which pose a serious threat for human health. Their specific properties make it possible that these substances may linger in soil and water for many years. These are the reasons why wells with water designed for drinking purposes have been subject of monitoring since 2006. This paper presents the results of monitoring research conducted in the soil-water environment within the framework in third phase of an ecological audit of land. The ecological audit of land made it possible to identify the cause and degree of the degradation, and helped formulate rationale for remedy decisions pertaining to the land (remediation/reclamation). The objective of the paper was to determine the pollution status of the soil-water environment and, subsequently, monitor (in years 2008-2010) the contents of the hazardous substances, namely trichloroethene and tetrachloroethene, within the area of the potential impact of metallurgical plant located in borders of the Main Underground Water Reservoir Wierzbica-Ostrowiec (GZWP 420) in in voivodeship Świętokrzyskie.
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Abstract

Biodiversity conservation cannot operate in Central Eastern European countries without a well-established monitoring system, that is dependent on the citizen scientists input. Here we analyse, based on a Polish case: (1) The contribution of NGOs to the national nature monitoring scheme and their collaboration with governmental and scientific institutions and (2) the motivation of citizen scientists to volunteer for NGOs’ monitoring activities. The study comprises a focus group interview, 30 in-depth interviews with coordinators, citizen scientists, experts and a 23 days long participant observation of a model NGO. We have assessed the monitoring input of NGOs as being a contributory factor influencing the biodiversity conservation effectiveness. The cooperation between governmental, scientific institutions and NGOs exists, but is dependent on national funding. Although NGOs highlight the lack of coherence in monitoring methodology, they are willing to join the biodiversity monitoring, especially at the European Ecological Network – Natura 2000 sites. On the other hand the trust concerning cooperation with citizen scientists is limited. However, despite this, they still turned out to be trustworthy partners. The most effective way to maintain cooperation with citizen scientists is to create a bond in a group and to provide them with the opportunity to develop their passion for nature. Our findings have shed light on the growing importance of citizen scientists in biodiversity governance, providing recommendations for development of the effective monitoring schemes based on the volunteer work of citizen scientists.
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Abstract

The major downside of blasting works is blast vibrations. Extensive research has been done on the subject and many predictors, estimating Peak Particle Velocity (PPV), were published till date. However, they are either site specific or global (unified model regardless of geology) and can give more of a guideline than exact data to use. Moreover, the model itself among other factors highly depends on positioning of vibration monitoring instruments. When fitting of experimental data with best fit curve and 95% confidence line, the equation is valid only for the scaled distance (SD) range used for fitting. Extrapolation outside of this range gives erroneous results. Therefore, using the specific prediction model, to predetermine optimal positioning of vibration monitoring instruments has been verified to be crucial. The results show that vibration monitoring instruments positioned at a predetermined distance from the source of the blast give more reliable data for further calculations than those positioned outside of a calculated range. This paper gives recommendation for vibration monitoring instruments positioning during test blast on any new site, to optimize charge weight per delay for future blasting works without increasing possibility of damaging surrounding structures.
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Abstract

The aim of this study was to identify a suitable lichen species for the long−term monitoring of heavy−metal atmospheric pollution in Svalbard. Cladonia and Cetraria s.l. species that have been widely used until now for assessing heavy−metal deposition in the Arctic are in decline over extensive areas of Svalbard, mainly due to climate change and over−grazing by reindeer. Cetrariella delisei , rarely used for biomonitoring, is still common and widespread in this area. Levels of Cr, Ni, Fe, Cu, Pb, Zn, Cd and Mn were measured in three lichen species: Cetrariella delisei , Cladonia uncialis , Flavocetraria nivalis and in a moss Racomitrium lanuginosum from Sørkapp Land, South Spitsbergen. The results imply that Cetrariella delisei can be safely compared to Cladonia uncialis for identifying the levels of heavy metals, but direct comparison between Cetrariella delisei and other species studied is more difficult owing to differences in levels of heavy metals even in samples from the same site.
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Abstract

Videoplethysmography is currently recognized as a promising noninvasive heart rate measurement method advantageous for ubiquitous monitoring of humans in natural living conditions. Although the method is considered for application in several areas including telemedicine, sports and assisted living, its dependence on lighting conditions and camera performance is still not investigated enough. In this paper we report on research of various image acquisition aspects including the lighting spectrum, frame rate and compression. In the experimental part, we recorded five video sequences in various lighting conditions (fluorescent artificial light, dim daylight, infrared light, incandescent light bulb) using a programmable frame rate camera and a pulse oximeter as the reference. For a video sequence-based heart rate measurement we implemented a pulse detection algorithm based on the power spectral density, estimated using Welch’s technique. The results showed that lighting conditions and selected video camera settings including compression and the sampling frequency influence the heart rate detection accuracy. The average heart rate error also varies from 0.35 beats per minute (bpm) for fluorescent light to 6.6 bpm for dim daylight.
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Abstract

The paper presents a construction of a system for measurements of pH, concentration of calcium ions and concentration of heavy metal ions in water. Three fiber optic sensors in flow configuration were designed and tested. The system is fully automatic and can be used for water quality monitoring.
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Abstract

An on-line optimising control strategy involving a two level extended Kalman filter (EKF) for dynamic model identification and a functional conjugate gradient method for determining optimal operating condition is proposed and applied to a biochemical reactor. The optimiser incorporates the identified model and determines the optimal operating condition while maximising the process performance. This strategy is computationally advantageous as it involves separate estimation of states and process parameters in reduced dimensions. In addition to assisting on-line dynamic optimisation, the estimated time varying uncertain process parameter information can also be useful for continuous monitoring of the process. This strategy ensures that the biochemical reactor is operated at the optimal operation while taking care of the disturbances that are encountered during operation. The simulation results demonstrate the usefulness of the two level EKF assisted dynamic optimizer for on-line optimising control of uncertain nonlinear biochemical systems.
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