Alexandru Salceanu

Digital Twin (DT) implementations in electrical and industrial systems are governed by fragmented ISO/IEC and IEC standards spanning terminology, architecture, interoperability, lifecycle management, and cybersecurity. This paper proposes a mathematical framework that integrates these standards into a unified compliance model. A layered DT architecture is defined as a finite set of functional abstractions, and standards are linked to layers through a multivalued mapping and an incidence matrix. Traceability, interoperability, fidelity, and security/governance indicators are normalized and aggregated through a bounded weighted functional to obtain a deterministic compliance score. The model is then extended by treating selected indicators as random variables, which enables probabilistic maturity classification and Monte Carlo-based robustness analysis. The resulting functional is bounded, monotone, and stable under bounded perturbations. Numerical experiments on a synthetic portfolio illustrate deterministic scoring and uncertainty effects. The framework provides a proof-of-concept basis for structured DT compliance assessment across heterogeneous electrical systems; however, broader empirical validation is still required before operational deployment.

There is a special concern for measuring and simulating low-frequency magnetic fields generated by underground power cables, particularly in human exposure studies. In the present study, an accurate 2D finite element model for computing magnetic fields generated by three-phase underground power cables with solid bonding is proposed. The model is developed in ANSYS Maxwell 2D low-frequency electromagnetic field simulation software for a typical 12/20 kV (medium-voltage) three-phase underground power cable in both trefoil and flat formations, but it can be adapted to any cable system. Model validation is achieved by analytical computations conducted with a software tool based on the Biot–Savart law and the superposition principle. RMS magnetic flux density profiles calculated at various heights above the ground with these two methods correlate very well. This is also true for induced shield currents. The application of the finite element model to multiple three-phase power cables laid together is also considered.

The article establishes the relevance of researching the importance of applied competencies and learning results in the standard of higher education for obtaining the bachelor's degree in the specialty “Information and measurement technolo- gies”. To achieve the goal, the description and requirements of competencies and learning results were analyzed, and an algorithm for group expert assessment of their importance was proposed and substantiated. Based on the assessment, the priority of profes- sional competencies and learning results was established. The most important competencies and learning results that can signifi- cantly influence the quality of education in the specialty are determined. Competences and learning results with the least impact on the quality of education in the specialty have been identified, which may indicate their formal nature. To better balance the system of competencies and learning results, it is necessary to pay special attention to those that have the least influence during the next revision of the standard of higher education for the training of bachelors in the specialty “Information and measurement technolo- gies”. The changes to the description of competencies and learning results proposed by the experts take into account the current trends in the development of the industry, provisions of current legislation, regulatory documents, and established terminology in the field of metrology and information and measurement technologies.

The article presents the results of comparative expert research to establish the importance of the applied national criteria for the quality of the educational program (CQEP) of higher education institutions (HEIs). For these studies, a group expert assessment of the importance of the CQEP for the educational program (EP) in the field of computer-integrated technologies was applied. The teaching staff of two universities is involved in conducting such an evaluation: The State University of Telecommunications (Ukraine) and the Gheorghe Asachi Technical University of Iași (Romania). To conduct this research, the existing CQEP and their sub-criteria and a special algorithm of group expert evaluation were used. It has been established that the most important CQEP and their sub-criteria include, first of all, CQEP regarding human resources, the educational environment, material resources, and the structure and content of the EP. The greatest spread of experts’ opinions (from the weightiest to the least weighty) can be stated for the sub-criteria of CQEP regarding access to EP and recognition of training results and transparency and publicity. With this in mind, this CQEP sub-criteria requires close attention when revising them for a better balance of the CQEP sub-criteria system. Harmonization of the list of fields of knowledge and specialties for which higher education students are trained with the International Standard Classification of Education, as well as the national terminological and conceptual apparatus with the international one, should be considered extremely appropriate in Ukraine. The issue of prioritizing the preparation of higher educational institutions for the accreditation of the EP, meeting the most essential requirements of the sub-criteria of the CQEP, and taking into account their significant number, remains relevant. This also determines the relevance and necessity of conducting special expert studies on the comparison of the importance of CQEP for different fields of knowledge.

The starting point of this paper is based on the need to design energy storage systems as correctly as possible, given that renewable energy sources, characterized by unpredictability and instability, will represent 57% of the world’s electricity production in the very next 10 years. Any large scale photovoltaic or wind power plant project must also contain a distinct part of a properly sized storage system. For the concrete case of Romania, are analyzed the seasonality index and practical potential (averaged over the entire surface of the country). These parameters influence the amount of electricity that can be produced by a certain photovoltaic plant within a year, including from the perspective of designing a system of adjacent storage. Then, for a certain geographical location, other four complementary parameters are customized and analyzed in detail. They all together provide essential information regarding the worst cases of solar illumination, for a certain number of consecutive days and for each month of the year. The calculation of these parameters was possible using the data made available by the open-source platform of the Power project supported by NASA. It is presented how to use this online tool, very functional for any calculation of electrical energy storage systems intended to ensure the autonomous operation of a photovoltaic plant not connected to the power grid. The results of the calculation of these four parameters associated with four representative locations in Romania are presented. These outputs can be displayed in graphical or tabular form. At the end there are presented considerations and comments regarding the interpretation, comparison and use of this data.

The paper presents a series of obtained results regarding the signal processing of non-electrical biological signals. To implement an application that helps people who specialize in the interpretation of entered data, such as the security of medical data. A well-known and difficult to interpret example is the respiratory signal, which is not associated with variations in electrical voltage. Therefore, with the help of some transducers, the electrical signal is associated with the respiratory signal, which can be affected by noise. The presence of these noises can be corrected by using high-performance filters, such as digital filters. A graphical interface has been developed in MATLAB 2021B for digital filtering of these signals. All necessary filtering functions have been introduced. For a user-friendly design, App Designer was used, an interactive development environment for designing programming applications that have a number of well-established functions. Programming was done using the MATLAB editor. By means of the predefined buttons the user can load the raw biological signals or choose the desired filter. At the same time, different digital filters have been implemented that can be selected from the interface: Butterworth, High pass, Low pass or Notch. To validate the filtering results, the publicly available database “ICBHI 2017 Challenge” has been accessed. Be a complex field that requires knowledge of electrical engineering and medical bioengineering to be understood and treated correctly.

Managing cardiopulmonary rehabilitation in patients with COVID-19 remains a global challenge due to the facets of this virus. The technologies used in the rehabilitation of post-COVID-19 patients fail to keep pace with the global epidemiological developments. The purpose of this article is to review the medical technologies used in post-COVID-19 cardiopulmonary rehabilitation and the innovations that have allowed us to adapt and care for our patients. The pandemic highlighted the need for seismic changes in diagnostic and rehabilitation paradigms. We discuss advances in telemedicine and telemedicine-based rehabilitation, remote patient monitoring and emerging technologies used in cardiopulmonary rehabilitation. The rapid adoption of modern technologies in the practice of post-COVID-19 cardiopulmonary rehabilitation is promising and can improve patients’ access to complex rehabilitation programs with outstanding results.

As the fundamental element that determines the well-being of each individual, health has become a growing cause of awareness and concern nowadays, as most people put more emphasis on daily activities to the detriment of health-care. In this paper, such a care system has been created and designed, allowing patients to daily store some vital parameters and transmit them through the cloud or in emergencies through mobile networks: in the form of a direct text message to the doctor's emergency number. A set of three parameters can be monitored: pulse, oxygen saturation in the blood and electrical activity of the heart which is known in literature as ECG. There is also a GPS module to determine the exact location, these being interfaced with an Arduino Mega development board. Vital parameters can be viewed on both the device and a laptop in order to download the recording history.

The paper presents an exergetic analysis of a magnetic regenerator in the current context of artificial cold production. Methods for calculating the exergetic balance for a group of physical processes were presented as component parts of integral processes. If we examine the heat transfer process and contemplate the calculation formulas of entropy generation and exergy losses, we see that in this case, the situation is much clearer than the mass exchange process. In the second case, the results obtained give the possibility to make only some qualitative comparisons. In technological processes we can find a much richer range of cases in which the specifics of energy and exergetic are not yet clear to the end. And, of course, the first and second principles of thermodynamics should be applied to their study. The results acquired after modeling in MatLab environment allow obtaining a numerical model of a magnetic regenerator performed on the principle of parallel gadolinium plates, operating at room temperature.