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The intensive development of photovoltaic (PV) micro-systems contributes to increased interest in energy efficiency and diagnosing the condition of such solutions. Optimizing system energy efficiency and servicing costs are particularly noteworthy among the numerous issues associated with this topic. This research paper addresses the easy and reliable diagnosis of PV system malfunctions. It discusses the original PV system energy efficiency simulation model with proprietary methods for determining total solar irradiance on the plane of cells installed at any inclination angle and azimuth, as well as PV cell temperature and efficiency as a function of solar irradiance. Based on this simulation model, the authors developed procedures for the remote diagnosis of PV micro-systems. Verification tests covered two independent PV systems over the period from April 2022 to May 2023. The obtained results confirm the high credibility level of both the adopted energy efficiency simulation model and the proposed method for diagnosing PV system functional status. [ABSTRACT FROM AUTHOR]

An education system can be considered as an anthropotechnical system consisting of an education subject (e.g., trainee, operator), examiner (teacher), system decision maker (e.g., teaching module coordinator), and the environment (e.g., administrative, social, IT). The outcomes of this system are the knowledge and skills acquired by a trained student. The educational effect is usually diagnosed in the form of an exam or test. The study addresses the issue related to the credibility of applied assessment methods, knowledge qualification levels, and assessment errors. The analysis is conducted in accordance with the principles applied in statistical quality control when studying product population defectiveness. Using known methods for testing product defectiveness, the authors characterized the trainee educational effect (i.e., his/her knowledge and skill level) in a technical manner. The probability of an event wherein the examined person demonstrating a specific knowledge level achieves an adequate grade, has been adopted as the reliability measure. The conducted calculations provided graphs of the reliability functions involving the grades received within the "traditional" examination and testing process. The authors suggested an application that tests a SCADA system user, based on tools known to the trainee. The application was developed using the SCADA suite used as a visualization element in distributed control systems. This application enables the automation of the operator diagnosis process. [ABSTRACT FROM AUTHOR]

In light of the rapidly growing number of photovoltaic micro-grids, the modelling of their short-term power yields based on meteorological measurements is increasing in significance. This requires the knowledge of total and diffuse instantaneous solar radiation; however, most meteorological stations conduct actinometric measurements only with regard to total solar radiation, especially on a minute scale. This paper contains an analysis of the currently used PV cell mathematical model and suggests its modification aimed at calculating PV cell power with satisfactory accuracy, without the knowledge of diffuse solar radiation. Three function families were proposed to approximate the relationship between diffuse irradiance and the total and theoretical total irradiance variance for a cloudless sky. A program has been implemented to identify functions from the aforementioned function families. It leverages an evolution strategy algorithm and a fitness function based on the least-squares point method. It was employed to calculate the desired functions based on actual measurement data. The outcome was the sought-after dependence that enables predicting diffuse irradiance based on more frequently available measurement data. [ABSTRACT FROM AUTHOR]

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Industrial networks combine elements of distributed control systems: process stations, operator stations and engineering stations. DCS stations often communicate using a dedicated, closed communication protocol. The industrial networks can be also used to manage communication between the stations of various systems, separate in terms of configuration. The process station communicates here with an external operator station, that is the SCADA system. For this purpose, the process stations and the SCADA systems can also communicate according to standard communication protocols, e.g. Modbus TCP. The paper examines the selected variants of diagnosing the communication status between the process station and the external operator station conducted according to the Modbus TCP protocol. The practical methods of finding the communication system unfitness causes are discussed. [ABSTRACT FROM AUTHOR]

This paper is devoted to deliberations on transmittance measurement system properties and potential Pilot- Helicopter-Environment (P-H-E), in the security context of this system. Based on the operator's transmission of the Pilot-Helicopter (P-H) and the results of the stability studies, it is possible to obtain the answer about the scope of acceptable - for safety reasons - changes the operator's transmission coefficients. On the other hand, the potential recognition allows the inference about the properties of the P-H-E system in safety and reliability areas. The basis of this interference is the assumption concerning the system which is suitable for the safe implementation of tasks in certain conditions and if the P-H system has a required stability supply at the specified time. [ABSTRACT FROM AUTHOR]

This article explores the quality of information acquired from weather station sensors. A review of literature in this field concludes that most publications concern the analysis of data acquired from weather station sensors and their characteristic properties, estimating the missing values from the data, and assessing the quality of weather information. Despite the large collection of studies devoted to these issues, there is no comprehensive approach that would consider the modelling of information uncertainty. Therefore, the article presents a proprietary method of analysing and modelling the uncertainty of the weather station sensors' information quality. For this purpose, the structure of a real meteorological station and the measurement data obtained from it were analysed. Next, an information quality model was developed using the certainty factor (CF) of hypothesis calculation. The developed method was verified on an exemplary real meteorological station. It was found that this method enables the improvement of the quality of information obtained and processed in a multi-sensor system. This becomes practical when the influence of individual measurement system elements on the information quality reaching the recipient is determined. An example is furnished by a demonstration of the usage of two sensors to improve the information quality. [ABSTRACT FROM AUTHOR]