Technical Condition Research Articles

A study of applicability of instrumented indentation method to determine the mechanical properties of thermoplastic

The article deals with the method of instrumental indentation as an effective tool for studying the mechanical properties of thermoplastics. The method allows to determine such material properties as hardness, modulus of elasticity, rheological characteristics. The paper presents a review of examples of using the method of instrumental indentation to solve research problems in studying the properties of various types of polymeric materials, describing the parameters that affect the results of measurements. Analyses and experimental studies of the method’s capabilities were carried out on the example of high-density polyethylene, which is used in the production of gas pipelines. The results showed the applicability of this method in studying the material properties of polyethylene (PE) gas pipeline pipes for diagnosing their technical condition. In this work, samples that have been in service for a long time and a sample of new pipe were investigated. It has been revealed that the hardness values of polyethylene samples of different service life as an indicator of resistance to plastic deformation under static loads are quite close, while the rheological properties differ significantly. This peculiarity should be taken into account when conducting various mechanical tests, since the rate of load increase during such tests will significantly affect their results. It was found that the values of hardness and modulus of elasticity decrease with increasing indenter dwell time under load due to stress relaxation in the deformed region under the indenter. The influence of polyethylene structure on its mechanical properties is considered. It is also revealed that the modulus of elasticity of polyethylene samples multiply increases when the degree of crystallinity changes from 48 to 56%. The article describes the prospectivity and efficiency of using the method of instrumental indentation to analyse the elastic-plastic and rheological properties of thermoplastics, as well as their relationship with the crystal structure.

Issues of determining the technical condition of agricultural machinery

The article presents the results of studies aimed at determining the criterion for the further use of agricultural machinery that has reached its limit state: to carry out major repairs or to dispose of it, preserving material resources as much as possible, as required by the principles of the circular economy.

Desempeño Productivo y Fisiológico del Pimiento (Capsicum Annuum L.) Influenciado por Biofertilizantes Orgánicos

Organic biofertilizers represent a sustainable alternative to improve plant growth and agricultural productivity. This study evaluated the effect of Rosbusterra, Humistar WG, and Algas 600 on pepper plants (Capsicum annuum L.) under field conditions at the “La María” farm of the Technical State University of Quevedo. A completely randomized design (CRD) with four treatments and three replications was applied. Mean comparisons were conducted using Tukey’s test at a 5% significance level. Variables assessed included plant height, stem diameter, days to flowering, fruit length and diameter, fresh and dry biomass of leaves, stems and roots, root length, fruit number and weight, yield (kg ha⁻¹), and economic analysis. Treatments were applied 15 days after transplanting. The biofertilizers significantly improved plant height, flowering time, and fruit characteristics. Rosbusterra showed the highest vegetative growth with 58.20 cm and 74.13 cm at 30 and 45 days, respectively. Humistar WG achieved the highest yield with 42,573.65 kg ha⁻¹ and a benefit–cost ratio of 1.93. No significant differences were observed in biomass or root length. Rosbusterra and Humistar WG were the most effective treatments. The application of the organic biofertilizer Humistar WG increased fruit number per plant, fruit weight, and overall yield.

COMPREHENSIVE ASSESSMENT OF ENERGY EFFICIENCY OF PUMPING EQUIPMENT WITH ADJUSTABLE DRIVE

The article presents a methodology for comprehensive assessment of the energy efficiency of pumping equipment equipped with variable-speed drives. The influence of frequency control on the energy consumption of pumping systems under various operating conditions is analyzed. An algorithm for calculating specific energy consumption is proposed, taking into account the technical characteristics of the drive, hydraulic load, and consumption profile. Practical application examples of the methodology are provided based on experimental and simulation data. The results obtained confirm the feasibility of implementing variable-speed drives as an effective means of improving the energy efficiency of pumping systems. The proposed methodology can be used for the techno-economic justification of modernization or the design of new facilities for water supply, wastewater treatment, and other technological systems based on pumping equipment. The use of a regulated electric drive, in particular a frequency converter, allows you to optimize the operation of pumps in accordance with changes in load, which helps reduce energy consumption. However, for an objective assessment of efficiency, a comprehensive approach is required, which takes into account not only changes in electricity consumption, but also hydraulic efficiency, operating characteristics, technical condition of the equipment and the economic feasibility of investing in modernization.

RESTORATION OF A FISHERMAN'S HOMESTEAD IN THE OPEN-AIR MUSEUM IN OPOLE

The paper addresses the issue of contemporary reconstruction and reconstruction of wooden architecture in open-air ethnographic museums, focusing on the example of the Opole Village Museum in Opole. The reconstruction process of three buildings – a cottage, a cottage building and a barn forming a fisherman's homestead – was analysed and the paper describes in detail the conservation methods applied, the adaptation process and the technological and ideological challenges involved in this kind of undertaking. The study emphasises the value of integrating traditional construction techniques with modern solutions, enabling the faithful reproduction of historic architecture while adapting it to new educational, exhibition and training functions. The analysis includes an assessment of the technical condition of the preserved materials, methods for their reuse and the impact of advanced monitoring technologies on the preservation and durability of the reconstructed buildings. It also highlights limitations of biological degradation of wood and the challenges of restoring authenticity in changing spatial conditions. The importance of open-air museums in the protection of cultural heritage was highlighted, in that they play a vital role in preserving the material aspects of historic buildings whilst also serving as a key educational and promotional tool for traditional rural culture. The findings emphasised the necessity of a multifaceted approach, integrating field research, historical documentation analysis and innovative diagnostic technologies. The article emphasises the necessity for additional research into monitoring and preservation methods that can contribute to more effective protection of wooden architecture, while ensuring its durability and functionality in changing environmental conditions.

Justification of the provisions of the methodology for performing ground photogrammetric survey of unfinished construction projects

This article presents the results of a study that substantiates the provisions of a methodology for conducting terrestrial photogrammetric surveys of unfinished construction objects using a dual-camera system. The relevance of this work stems from the necessity of obtaining reliable information about the actual condition of structural elements at unfinished construction sites, which is important for making decisions regarding necessary actions for restoration, demolition, or conservation of the object. For the study, a terrestrial photogrammetric survey was carried out using a dual-camera photogrammetric system on an unfinished construction object. The variable parameters considered in performing and processing the photogrammetric survey were shooting frequency, method of image alignment, and the application of an optimization procedure. The results obtained showed that to ensure successful image alignment, it is necessary to consider the minimum required shooting distance between frames and to apply an optimization procedure based on the accurate coordinates of the centers of reference images. The use of general pre-selection during image alignment allows for the best results in terms of the final model’s accuracy. The conclusions drawn enable the formulation of the main provisions of a methodology for conducting terrestrial photogrammetric surveys of unfinished construction objects using a dual-camera system, ensuring the acquisition of three-dimensional models for subsequent analysis of the technical condition of structural elements.

On One Special Problem of Blades Identifi cation in Monitoring the Technical State of Gas Turbine Engine Air-Gas Channel

This article is devoted to the problem of "targeted" fixing of the measurement results of spatial position of the blades’ tips of compressor or turbine of gas turbine engine (GTE) to a specific struct ural element of the power plant (blade) in monitoring the state of engine’s gas-air channel under limitations on use of diagnostic equipment and, in particular, the impossibility of installing the shaft’s angular position sensor, that ensures the synchronization of primary converters polling with the rotation period of the turbomachine rotor. The diagnosis of disruptive and surging phenomena in GTE compressor, detection of foreign objects entering the gas-air path of the engine, determination of fatigue failure of the blades are the typical examples of the tasks that require binding of the measurement results to each individual blade on a rotor wheel. The proposed solution is based on the analysis of a unique set of radial clearance values for the complete ensemble of rotor blades with the comparison of the current and previously obtained "reference" images of the turbo compressor’s bladed wheel. Two algorithms for blades’ number determining are considered. The algorithms do not require a separate channel for synchronization and use the minimum Euclidean distance and the maximum value of the cross-correlation function between the elements of the "reference" and current arrays of codes as criteria for blades’ identifying. The results of the performance test of both algorithms on a laboratory bench with a real compressor wheel are presented. It is shown that the criterion based on cross-correlation function calculation has higher noise immunity, and therefore it is the most preferable for practical implementation in actual practice measurement systems. Low computational complexity of the criterion allows to use it at the microprocessor level and to reduce the measuring system hardware.

Assessment of changes in a technical condition of railway bridges using a novel probabilistic algorithm

Planning of rehabilitation work is important for the safety of transport infrastructure. This problem needs to be properly solved, therefore a new algorithm for planning railway bridge maintenance is proposed. The input data come from periodic inspections that assess the technical condition of a bridge. These assessments are processed using hybrid Extended Fuzzy Analytic Hierarchy Process and Dominant Analytic Hierarchy Process methods. The main part of the algorithm is the Statistic Bridge Analyser, which allows a multi-variant analysis of the impact of inaccuracy and uncertainties in sub-assessments. It also takes into account a relationship between individual bridge components and estimates missing assessments using archive data. The algorithm performance has been confirmed by analysing nine different scenarios involving ranking of 10 selected railway bridges on Maintenance, Repair & Rehabilitation (MR&R) list. It has been demonstrated that even a small error in the sub-assessment of the technical condition of one element can result in a significant change in assessment of the bridge technical condition. Considering the relationship between criteria also generates changes in the final assessment of the bridge technical condition and may result in changes in position on MR&R list. This allows to avoid sudden failures, especially with limited financial resources.

Statistical Estimation of Reliability Values for Large-Panel Buildings Based on Passportization Results

In 2017-2018 and 2023-2024, a full passportization of the housing stock of apartment buildings in the city of Almaty (Republic of Kazakhstan) was carried out for the first time. The database includes 2666 multi-story large-panel buildings of different numbers of stories, from 2 to 9 floors. The aim of this study is to assess the reliability of standard-series large-panel buildings based on previous experimental research and passportization results, as well as to evaluate their seismic resistance and reliability using passportization data. The latest earthquakes in Almaty have allowed for refinements in seismic impact models. Therefore, the reliability assessment has been conducted considering this information using the Monte Carlo method. The technical condition of large-panel buildings has been assessed. The earthquake recurrence is taken into account according to the current "Map of seismic zoning of the Republic of Kazakhstan". Reliability value for the whole group of large-panel buildings has been obtained. It is revealed that large-panel buildings with the first flexible or brick floor are not earthquake-resistant. For the first time, the theoretical analysis of reliability and failure values for 2 types of large-panel buildings with the use of experimental data is performed. Regional peculiarities of seismic impact for Almaty City are taken into account. The results of reliability and failure values estimations are used for practical recommendations on risk reduction and expected losses in case of possible earthquakes. The novelty lies in the reliability and failure assessment based on the large-scale passportization of the housing stock in Almaty. It is established that the main types of large-panel buildings are earthquake-resistant. Estimates of earthquake resistance according to the results of passportization and the results of reliability calculations coincided. It is proposed to reinforce large-panel buildings with the first flexible or brick floor (33 buildings). The method of reinforcement should be determined by special studies. Doi: 10.28991/CEJ-2025-011-05-019 Full Text: PDF

Multi-level processing of vibroacoustic signals for improving the diagnostics of gas turbine engines

The object of this study is the process of monitoring the technical condition of an aircraft gas turbine engine (GTE). One of the most dangerous causes of accidents is damage caused by foreign objects, in particular small metal particles, hailstones, bolts, fuselage fragments, etc., entering the engine turbine during flight or during takeoff and landing. The task addressed was to improve the methods of gas turbine engine vibroacoustic diagnostics, which would increase its sensitivity to small changes in diagnostic signals caused by the ingress of small foreign objects into the engine turbine. To solve this problem, it has been proposed to use multi-level processing of vibration signals obtained as a result of physical modeling of the rotating system (RS) and simulation of the ingress of small foreign objects. Multi-level processing combines the use of time-frequency, bispectral, and fractal analysis methods to determine the quantitative integrated diagnostic indicator – Minkowski dimensionality. The following average values of Minkowski dimensionality were obtained for the estimates of the bispectral modulus: without external influence – 1.075; ingress of small foreign objects – 1.01; friction of the blades against a foreign object as a result of its ingress into the RS turbine – 1.21. It has been established that an increase in the Minkowski dimensionality indicates the development of an operational disturbance caused by the ingress of foreign objects, even very small ones. This paper reports experimental confirmation of the effectiveness of using multi-level processing of vibration signals for diagnosing operational disturbances due to the ingress of foreign objects into RS. It has been established that multi-level processing makes it possible to detect hidden trends in a noisy signal that are difficult to detect using conventional processing methods

Substantiating Restoration of Bearings Mounting Area in Transport Transmission Shafts with Iron-Chrome Coatings

Introduction. During the operation of cars and other vehicles, the process of changing technical condition of parts and units takes place. With increased operation time and mileage, the failure rate increases, which leads to the problem of maintaining equipment in working condition through high-quality maintenance and repair. Parts repair has been a way to extend the service life of equipment by replacing or restoring the worn parts. Due to the problems of quality supply, the urgency of restoration becomes obvious. Numerous problems with high-quality spare parts cause the restoration as a way to overcome the above-mentioned problems. However, the restoration method should meet certain requirements, in particular, repair costs should not exceed 50% of the cost of a new part and durability should be at the level of 80-100% of the new part. Therefore, this article presents the results of research on a new method of restoring parts with iron-chromium coatings in order to maintain equipment in good condition.Materials and methods. The investigation was based on literature analysis to study the restoration methods according to various criteria, such as durability, cost of use, wear resistance and other indicators. Also, based on a preliminary analysis, one of the promising methods was selected – iron-chromium coating. Preliminary research into the effect of acidity on the performance and quality of the coating has been carried out.Results. The study of iron-chromium coating obtained from the composition of an electrolyte with 0.4-0.6 acidity has made it possible to obtain a coating with a sufficiently high microhardness (up to 8,500 MPa), current output (up to 40%) and deposition rate (up to 200 microns/hour). The resulting coating also has demonstrated a small number of microcracks, which made it possible to delay lubrication and provide increase in wear resistance.Discussion and conclusion. As a result, the coating obtained has shown good physical and mechanical properties. Therefore, it will be possible to use this method to restore the mounting area of bearings in transmission shafts operating under abrasive wear.

Assessment of the Technical Condition of Roofs of Large-Panel Residential Buildings Erected in Belarus before 1993

The paper provides an assessment of the technical condition of combined insulated rolled roofs with a sequential arrangement of layers and ventilated roofs of large-panel residential buildings of standard series built in Belarus before 1993. The results of field studies have shown that after more than 30 years of operation, the technical condition of the materials of the main structural layers (bearing structure of the coating, vapor barrier, materials of the thermal insulation layer) is operable. Defects that have a negative impact on the functional suitability of roofs as a whole are recorded only in the main waterproofing carpet and cement-sand screed. It has been established that the causes of the appearance and development of operational defects (loss of coarse-grained sprinkling with roofing material, stagnation of water on the roof, cracks in the bitumen coating layer of the rolled roof, swelling between the layers of the rolled roofing carpet) are “harsh” operating conditions of roofs: constant, throughout the entire period of operation, influence on the materials of atmospheric influences, as well as violations of the technology of roofing work. To maintain the working condition of combined insulated rolled roofs of large-panel residential buildings operated for more than 30 years, the main material and financial costs fall on partial repair of the waterproofing carpet, including local repair of cement-sand screed. The reason for the local destruction of the roof screed of large-panel residential buildings built before 1993 is its insufficient frost resistance, due to the requirement laid down in the design of such buildings to ensure the strength of the screed material in terms of frost resistance for the rated service life of large-panel residential buildings, i.e. for at least 30 years. Considering that the standard service life of all large-panel residential buildings built before 1993 is more than 30 years, the problem of ensuring the operability of the screed will become increasingly relevant. It is proposed to extend the service life of the screed without repairs and reduce heat loss through the combined coating to install an inversion roof on the existing roof.

ПОВЫШЕНИЕ НАДЕЖНОСТИ ТЯГОВОГО ПОДВИЖНОГО СОСТАВА МЕТОДАМИ ПРЕДИКТИВНОЙ АНАЛИТИКИ ПОКАЗАТЕЛЕЙ МОТОРНОГО МАСЛА

Locomotive transport is one of the relevant development areas in the general infrastructure of the sectoral economy. At the moment, a number of tasks and problems related to upgrading existing and the creation of new engine diagnostic systems for this vehicle are being updated. The main purpose of the presented paper is to analyze the possibility of improving the reliability of traction rolling stock by integrating predictive analytics tools for engine oil quality. The authors actualize the tasks related to the need to introduce innovative approaches to analyzing engine oil indicators in real time in order to take appropriate measures to adjust its composition. The paper contains data on the solution to this problem by using predictive analytics tools together with intelligence technologies for monitoring engine oil indicators. The results of the paper describe a possible solution to the problem by using artificial neural networks in determining the current state of the unit, as well as predicting possible changes in the technical condition of the engine relative to operating time. The results also include an algorithmic interpretation of the solution of the initial problem through the introduction of predictive analytics tools. The novelty of the work is in an attempt to comprehensively study and systematize the results regarding the use of predicative analytics to improve the reliability of traction rolling stock by analyzing engine oil indicators. The paper materials are of practical importance, as it is possible to use them to create applied solutions in subsequent research.

АНАЛИЗ МЕТОДОВ ОЦЕНКИ И ОБЕСПЕЧЕНИЯ БЕЗОПАСНОСТИ ДВИЖЕНИЯ ВАГОНОВ

The study objective is conditioned by the need to ensure the safety of car operation, which is a key aspect of the efficient and safe functioning of railway transport. With the increasing volume of freight and passenger traffic, the importance of developing and applying methods for assessing and ensuring traffic safety is increasing. To achieve this objective, the following task is defined: to analyze existing methods for assessing the safety of railcars, identifying their advantages and disadvantages, as well as identifying promising areas for improving the reliability of rolling stock operation. The main research method is a comparative analysis of modern methods for assessing the safety of railcars and the identification of key criteria affecting the safety of operation. Special attention is paid to innovative technologies for monitoring and diagnosing the technical condition of cars. The novelty of the work is in the attempt to sort out innovative methods for assessing and ensuring the safety of railcars, as well as in presenting the results of assessing their effectiveness, which makes it possible to identify the most effective approaches and identify areas for their further use and improvement. The study results open up a new direction in improving methods for assessing and ensuring the safety of rolling stock, taking into account trends in scientific and technological progress. The paper materials can be useful to specialists in the field of railway transport, engineers involved in the operation and maintenance of cars, as well as to developers of new technologies for ensuring traffic safety. The results obtained can be applied to increase the level of safety of railway transportation and minimize emergency situations.

Mechanical, Thermal, and Environmental Energy Harvesting Solutions in Fully Electric and Hybrid Vehicles: Innovative Approaches and Commercial Systems

Energy harvesting in the automotive sector is a rapidly growing field aimed at improving vehicle efficiency and sustainability by recovering wasted energy. Various technologies have been developed to convert mechanical, thermal, and environmental energy into electrical power, reducing dependency on traditional energy sources. This manuscript provides a comprehensive review of energy harvesting applications/methodologies, aiming to trace the research lines and future developments. This work identifies the main categories of harvesting solutions, namely mechanical, thermal, and hybrid/environmental solar–wind systems; each section includes a detailed review of the technical and scientific state of the art and a comparative analysis with detailed tables, allowing the state of the art to be mapped for identification of the strengths of each solution, as well as the challenges and future developments needed to enhance the technological level. These improvements focus on energy conversion efficiency, material innovation, vehicle integration, energy savings, and environmental sustainability. The mechanical harvesting section focuses on energy recovery from vehicle vibrations, with emphasis on regenerative suspensions and piezoelectric-based solutions. Specifically, solutions applied to suspensions with electric generators can achieve power outputs of around 1 kW, while piezoelectric-based suspension systems can generate up to tens of watts. The thermal harvesting section, instead, explores methods for converting waste heat from an internal combustion engine (ICE) into electrical power, including thermoelectric generators (TEGs) and organic Rankine cycle systems (ORC). Notably, ICEs with TEGs can recover above 1 kW of power, while ICE-based ORC systems can generate tens of watts. On the other hand, TEGs integrated into braking systems can harvest a few watts of power. Then, hybrid solutions are discussed, focusing on integrated mechanical and thermal energy recovery systems, as well as solar and wind energy harvesting. Hybrid solutions can achieve power outputs above 1 kW, with the main contribution from TEGs (≈1 kW), compared to piezoelectric systems (hundreds of W). Lastly, a section on commercial solutions highlights how current scientific research meets the automotive sector’s needs, providing significant insights for future development. For these reasons, the research results aim to be guidelines for a better understanding of where future studies should focus to improve the technological level and efficiency of energy harvesting solutions in the automotive sector.

A case study of the use of statistical processing of the armature rotation irregularities for the diagnostics of locomotive traction electric motors

Locomotive Traction Electric Motors (TEMs) generate power to rotate the wheelsets of diesel or electric locomotives, electric or diesel multiple units. TEMs are the most critical parts of traction rolling stock on which exploitation costs, reliability and train traffic safety depend. The purpose of the article is to evaluate the possibility of diagnostics the technical condition of the TEM using the rotation irregularities of the armature shaft in the electric motor as a diagnostic parameter. The article analyses the main causes of TEM failures and methods for diagnosing electric motors in operation. The expediency of using the rotation irregularities of the armature shaft in the electric motor as a diagnostic parameter is substantiated. The structural flowchart of the device for measuring the rotation irregularities of the armature is presented. Diagnosing the mechanical part of an electric motor is chosen as an implementation example. The authors confirmed the connection between the technical condition of the electric motor and the statistical indicators calculated for the signal of the rotation irregularities of the armature shaft.

Improving the cadastral registration system for real estate objects based on their technical condition indicators

The article discusses the development of a systematic approach to creating a Unified Information Database on the technical condition of real estate objects across all urban and rural development areas. The necessity of this solution is justified by the current situation in urban planning, particularly after the enactment of Russian Federal Law No. 494-FZ on the Comprehensive Development of Territories (CDT). Decision-making regarding the renovation of large urban quarter territories has been hindered by the lack of data on the technical condition of most buildings. This situation is further exacerbated by the practice of conducting major repairs (FKR) without preliminary instrumental inspections, thus failing to address the actual causes of structural deterioration. The authors propose a systematic solution to this problem, involving the establishment of professionally trained units equipped with diagnostic instruments, standardized inspection methodologies tailored to building types, specialized software, and precise task assignments that account for the specific characteristics of the territory’s development. All inspections are conducted in accordance with territorial development plans and consolidated into a dedicated GIS-based real estate database in the form of specially developed Real Estate Passports. Data on the technical condition of each object, including key indicators such as structural strength, deformations, and physical-technical characteristics of materials, are aligned with current construction standards (SP and SNiP). This information is used in designing master plans for territorial development, planning major housing repairs, and within the Russian Federal Service for State Registration, Cadastre, and Cartography (Rosreestr) cadastral registration system. The article is based on extensive real-world experience in building inspections and urban renovation planning.

DIAGNOSTICS OF POWDER CHARGE DEGRADATION BY VIBROACOUSTIC SIGNALS OF GUNSHOTS

Since the degradation of a powder charge significantly affects the effectiveness of firing missions, can lead to the destruction of the gun and injury or death of personnel, there is a practical need for systematic monitoring of its condition, and known methods and diagnostic tools do not provide the ability to conduct operational control in combat conditions. No matter what method is used to control the condition of gunpowder charges, only a sample of a larger or smaller quantity is always inspected, so there is always a non-zero probability that a certain quantity of gunpowder with an excessively high degree of degradation will be included in the ammunition of a particular artillery weapon. In addition, during transportation and storage of weapons in active combat operations, they are inevitably exposed to a variety of atmospheric factors that can significantly damage them up to the point of complete unsuitability for their intended use, but without obvious visual signs of such damage. Therefore, it is important to be able to detect an unacceptable level of powder charge degradation in time and to distinguish it from other possible factors of ineffective firing directly in combat conditions. The purpose of the research is to experimentally validate the possibility of determining the degradation of charges in combat conditions by vibroacoustic signals of gunshots. The study analyzes existing methods for diagnosing the condition of powder charges and searches for new approaches to determining the level of powder charge degradation. For the first time, a technique for diagnosing the degradation of a powder charge based on the analysis of vibroacoustic signals of gunshots is proposed. The general structure of the system for recording vibroacoustic signals of shots based on surface- mounted piezoelectric sensors is proposed. Samples of practically obtained vibroacoustic oscillations and their statistical characteristics for artillery systems with different types of barrels and projectiles are presented. The obtained results can be used for further development of methods of vibroacoustic diagnostics of the technical condition of artillery weapons, including the degradation of the gunpowder charge.

Impact of seasons on industrial grounding resistance

A properly designed and constructed ground electrode should perform well for many years. It must be periodically inspected to know its current technical condition. This obligation falls on the installation’s owner. Depending on the function of the ground electrode in the entire installation, it may be a working, protective or lightning protection earth. The choice of a measurement method depends on its function in the installation. The paper presents the results of measurements of the ground electrode resistance of a selected technical facility, performed throughout the year. Repeating the measurements multiple times in different seasons of the year was dictated by assessing the impact of environmental conditions on the results of grounding system resistance measurements. Analysis of the results performed in various environmental conditions may be the basis for recommending those performing this type of measurement to choose the appropriate method and the best date for performing the measurements. Considering the significant impact of the proper value of ground resistance on the effectiveness of protection against electric shock and lightning, its measurements should be carried out with due care.

Processing and analysis of trolleybus traction data using LINQ technology

The paper presents the processing and analysis of the recorded trolleybus data using the LINQ (Language Integrated Query) software technology. The trolleybus data acquisition system collects a huge amount of electromechanical data in real time during the vehicle operation. These data are used for the analysis in post-processing mode. In this paper, the data processing has been performed to assess the technical condition of trolleybus batteries. Selected standard query operators of the LINQ technology have been implemented in the Windows Presentation Foundation (WPF) application to process the data and to determine the charge and energy stored in the battery. The LINQ technology has been proven to be useful for analysing large amounts of data recorded from trolleybuses.