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Boiling Water Reactor (BWR) employs the Pressure Suppression Pool (PSP) as a heat sink to prevent overpressure of the reactor vessel and containment. Steam can be injected into the PSP through spargers in normal and accident conditions and through blowdown pipes in case of a loss of coolant accident (LOCA). There is a safety limit on the maximum PSP temperature at which such steam injection might cause dynamic loads on the containment structures. The performance of the pool can be affected if thermal stratification is developed when temperature of the hot layer grows rapidly while cold layer remains inactive. Simulation of pool behavior during realistic accident scenarios requires validated models that can sufficiently address the interaction between phenomena, safety systems and operational procedures. Direct modeling of steam injection into a water pool in long-term transients is computationally expensive due to the need to resolve simultaneously the smallest space and time scales of individual steam bubbles and the scales of the whole PSP. To enable PSP analysis for practical purposes, Effective Heat source and Effective Momentum source (EHS/EMS) models have been proposed that avoid the need to resolve steam-water interface. This paper aims to implement mechanistic approaches previously developed by authors for the simulation of transient thermal stratification and mixing phenomena induced by steam injection through spargers in a Nordic BWR PSP. The latest version of the EHS/EMS models using the ‘Unit cell’ approach has been validated against integral effect pool tests and applied to plant simulations. Several scenarios with boundary conditions corresponding to postulated accident sequences were simulated to investigate the possibility of stratification development and the effects of activation of different systems (e.g., blowdown pipes, high momentum nozzle) on the pool behavior.

In this paper, we present a novel approach for segmenting planar regions in Digital Surface Models (DSMs) by adapting the Segment Anything Model (SAM), an open-source framework. Our approach specifically tailors SAM to recognize planar regions within given building footprints, employing the Low-Rank Adaptation (LoRA) technique. This adaptation benefits from a detailed and realistic synthetic dataset, coupled with a novel labeling strategy for planar regions in our ground truth, enhancing the model’s effectiveness and reproducibility. Unlike traditional plane detection techniques, our method consistently and accurately identifies equivalent planar regions across identical DSM inputs. Following the segmentation phase, we introduced a novel plane fitting algorithm to determine the parameters for each planar region. This enables us to refine the edges of these areas and utilize the resulting plane equations to construct precise, watertight 3D models of buildings. Despite its training on synthetic data, our model exhibits remarkable performance on both synthetic and real-world datasets, exemplified by its application to the Zurich dataset.

Advanced Pressurized Water Reactors (APWRs) and Boiling Water Reactors (BWRs) employ a suppression pool as a heat sink to prevent containment overpressure. Steam can be discharged into the pool through multi-hole spargers or blowdown pipes in both normal and accident conditions. Direct Contact Condensation (DCC) creates sources of momentum and heat. The competition between these two sources determines the development of thermal stratification or mixing of the pool. Thermal stratification is of safety concern as it reduces the cooling capability compared to a completely mixed pool condition. In this work we develop a scaling approach to prediction of the thermal stratification in a water pool induced by steam injection through spargers. Experimental data obtained from large-scale pool tests conducted in the PPOOLEX and PANDA facilities, as well as simulation results obtained using validated codes are used to develop the scaling. Two injection orientations, namely radial injection through multi-hole Sparger Head (SH) and vertical injection through Load Reduction Ring (LRR), are considered. We show that the erosion rate of the cold layer can be estimated using the Richardson number. In this work, scaling laws are proposed to estimate both the (i) transient erosion velocity and (ii) the stable position of the thermocline. These scaling laws are then implemented into a 1D model to simulate the thermal behavior of the pool during steam injection through the sparger.

The source base of the study consists of literary works of fiction and publicistic genre, letters of the Republic citizens and subjects of ancient Roman emperors, who bear witness of the attitude of contemporaries to the profession of a teacher, determine its prestige and social significance. This preconditioned the aim of the study to determine the social status of a Roman teacher. The authors claim that the latter depended on both formal and informal factors. However, personal level of professional achievements, attractive individual traits, morality, support from influential people were more important than belonging to a particular class of mentors or state regulation of education. The teacher's authority regulated his right to corporal punishment of students and influenced the amount of remuneration. The researchers believe, that a certain criterion to determine the prestige of the profession is the quantitative indicator of payment, as well as the regularity of its implementation. The teacher's wealth increased his place in the system of social relations and, conversely, was a consequence of patronage by the authorities. However, the incomes of most teachers remained low, which, in combination with other criteria of prestige of the job, allows to conditionally establish the status of a teacher at a level "below average".

The research of the structure of the phenomenon of self-realization among specialists in the digital sphere in the context of information and computer activities is presented. The authors analyzed the hierarchy and components of self-realization among IT workers with different sets of individual psychological characteristics, which, through clustering, were divided into three subtypes: (1) introverted-confident; (2) extroverted-active; and (3) extroverted-prosocial. The study involved 154 people, including 42 women and 112 men aged 22-44 (mean age = 32.09 ± 5.71); all of them were employees of leading Russian IT companies in Moscow. Following psychodiagnostic techniques were applied: Individual-Typological Questionnaire (ITQ) by L.N. Sobchik, Eysenck Personality Inventory (EPI) - introversion - extroversion scale, Strategic Approach to Coping Scale (SACS) questionnaire by S. Hobfoll, and Multidimensional Personality Self-Realization Inventory (MPSI) by S.I. Kudinov. The results showed that the structure of self-realization had its own specific features depending on the personality type of the IT employees. For the respondents of cluster I (introverted-confident personality type), the main variables of the self-realization process were optimism, internality and constructiveness, which led to success and a positive assessment of the self-realization process. For the respondents with extroverted-active characteristics in the hierarchy of personal self-realization, the key components of self-realization were social and corporate attitudes, egocentric motivation, internality, conservatism, and destructiveness. The respondents with extroverted-prosocial traits had pronounced subjective personal attitudes, internality, creativity, destructiveness, and social barriers, with predominant limiting factors of self-realization. The results of the study can be considered in the context of psychological support for the IT specialists based on their individual psychological traits.

RELEVANCE. Due to the difficulties of finding eigenvalues and proper functions for bodies with axial (cylinder) and central (ball) symmetries defined in classical methods from the edge Sturm-Liouville problems, including Bessel equations whose exact analytical solutions are not obtained (known only numerical solutions, described by approximation formulas), there is a need to develop analytical methods of their solution.THE PURPOSE. Using orthogonal methods of weighted residuals, an approximate analytical method for determining eigenfunctions and eigenvalues in boundary value problems with axial and central symmetry (cylinder, ball) has been developed.METHODS. The method is based on the use of orthogonal systems of coordinate functions and additional boundary conditions. Latter are in such a form that their fulfillment by the desired solution is equivalent to the fulfillment of the differential equation of the boundary value problem at the boundary points of the region, leading to its fulfillment inside the considered region. Moreover, the accuracy of the equation depends on the number of approximations, which, in turn, depends on the number of additional boundary conditions used. Using the orthogonality property of trigonometric coordinate functions included in a series representing eigenfunctions makes it possible to increase the accuracy of the fulfillment of the differential equation of the Sturm-Liouville boundary value problem and the accuracy of determining the eigenvalues. To satisfy the initial condition, its residual is compiled and the condition of its orthogonality to all coordinate functions is required. The orthogonality of trigonometric systems of coordinate functions with respect to the unknown constants of integration leads to a system of algebraic linear equations, the number of which is equal to the number of approximations. As a result, the fulfillment of the initial condition is simplified and the accuracy of its fulfillment is increased.RESULTS. The advantage of the method is that the resulting solution contains only simple algebraic expressions, excluding special functions (Bessel function, Legendre function, gamma function).CONCLUSION. Thus, bypassing direct integration over a spatial variable, the use of additional boundary conditions makes it possible to find a solution of any complexity of the equations of the Sturm-Liouville boundary value problem, which reduces to the definition of simple integrals.

This empirical study links emotional burnout with self-attitude. The contemporary pedagogical environment subjects school teachers to emotional burnout and professional deformation. On the one hand, the state and society have extremely high professional requirements for teachers, who strive to improve their psychological, pedagogical, didactic, methodological, and digital competencies. On the other hand, the social and financial insecurity forces school teachers to increase their workload at the expense of their physical and psycho-emotional recovery. The authors hypothesized that a particular self-attitude can trigger the burnout syndrome in teachers. They relied on the subject-activity approach to the emotional burnout syndrome to survey 237 secondary school teachers (169 women, 68 men; 32–40 y.o.). Their self-attitudes were identified by the personal differential method, W. Stephenson’s Self-Image Test, and V. V. Stolin and S. R. Panteleev’s Self-Attitude Test. The level of emotional burnout was measured using V. V. Boyko’s Diagnostics of Emotional Burnout. An expert assessment served as an additional method to identify the performance indicators. The empirical research revealed that the teachers with an adequately positive self-attitude demonstrated fewer symptoms of emotional burnout, which stayed at an initial stage. They managed to maintain high standards of working capacity and professional motivation, as well as effective vertical and horizontal social communication. The teachers with a less positive self-attitude experienced severe symptoms of burnout and professional deformation, which affected their professional activities. They were confrontational and complained about low motivation, poor performance, procrastination, etc. The data obtained may help to improve psychological support programs and psychological counseling in schools.

Resistance welding in large-scale manufacturing is carried out with a significant number of disturbances, the cumulative effect of which may exceed the capabilities of modern control equipment. Most resistance welding control systems used in industry to compensate for existing disturbances provide welding current phase control depending on the measured parameters characterizing the process of welded joint formation. The efficiency of such controllers is largely determined by the accuracy of measuring and setting the phase control parameters, which include the opening and conduction angles of welding thyristors. The paper shows that when switching on a contact machine, a phase shift of the mains voltage occurs in the load mode relative to the mains voltage in the idle mode. Using a simplified electric equivalent circuit of a contact welding machine, the paper describes the nature of the phase shift of the mains voltage. Circuit active resistance and inductance are selected as parasitic parameters of the mains. The authors simulated the electrical processes in the contact machine according to the three-loop equivalent circuit. The study shows the influence of mains parasitic parameters on the phase regulation stability, the features of the obtained current and voltage oscillograms. Depending on the mains and contact welding machine parameters, the phase shift magnitude ranges from fractions to units of an electrical degree. With welding current parametric stabilization by the mains voltage, the influence of mains parasitic parameters can be neglected. When the regulator operates in the mode of maintaining the secondary current numerical value, a decrease in the generated current relative to the specified one is observed. The authors proposed and tested a technique for determining the parasitic parameters of the supply mains based on the results of a short circuit test.

The relevance of the study is due to the poor development of the problem of professional self-realization of IT specialists. The specifi city of the professional activity of this category of employees imposes special requirements on their individual psychological characteristics, which ensure the success of self-realization of specialists engaged in information and computer activities. Purpose: to identify the specifi cs of self-realization of IT professionals with diff erent individual typological features. Hypothesis: a set of certain individual-personal characteristics forms diff erent individual-psychological types of IT specialists, which act as a prerequisite for professional self-realization of the subject of this profession. Participants: employees of leading Russian IT companies (Moscow) (N = 154) – 42 women and 112 men aged 22 to 44 (average age 32.09±5.71). Methods (tools). To study the individual and personal characteristics of IT specialists, the following were involved: “IndividualTypological Questionnaire – ITQ” (L. N. Sobchik), “Personality Questionnaire – EPI” (G. Eysenck), questionnaire “Strategies for Coping with Stressful Situations - SACS” (S. Hobfall). When identifying the specifi cs of self-realization of IT specialists with diff erent individual typological features, the “Multidimensional Questionnaire of Personal Self-Realization” (S. I. Kudinov) was used. Results: it was found that such characteristics as “anxiety”, “sthenicity”, “extraversion” and “lability” are leading ones in the structure of individual traits of IT-specialists. The dominant coping strategies of IT-specialists are “entering into social contact”, “search for social support”, “cautious actions”. As a result of cluster analysis, three types of individuality of IT-specialists were identifi ed and characterized: “introverted-confi dent”, “extroverted-active”, “extraverted-prosocial”. According to the results of a comparative analysis the data on the confi guration of the types of self-realization in each cluster are presented. It has been established that specialists of the “introverted-confi dent” type demonstrate the highest rates in all types of self-realization: personal, social and professional. This allows us to consider this type of personality as the main predictor of eff ective self-realization of IT specialist’s personality. Main conclusions: 1) there is a certain specifi city in the manifestation of self-realization of IT specialists with diff erent individual typological features; 2) the practical signifi cance of the study is emphasized in the context of psychological support for the professional self-realization of IT specialists, taking into account their personal characteristics.

Aim: to assess the blood level of biological endothelial damage markers in women with previous early-onset preeclampsia (еPE) during both the preconception (PC) stage and the first trimester of pregnancy.Materials and Methods. A prospective single-center cohort study was conducted. The control group comprised 40 women with uncomplicated pregnancies. The observation group consisted of 97 patients with a history of ePE, stratified based on pregnancy outcome into the comparison group (n = 59) characterized by a favorable gestational course, and the main group (n = 38) with relapsed еPE (30 patients were excluded from the study). Markers of systemic endotheliosis were determined in women at the PC stage and at 11–13 weeks of gestation: endothelin-1 (ET-1) and endothelial extracellular vesicles (EVs; CD-144).Results. At the PC stage, women in the control group and patients from the comparison group had comparable median (Me) ET-1 levels – 0.39 and 0.40 pmol/ml (p = 0.5935), respectively; at the same time, patients with relapsed еPE vs. control group had it significantly elevated (Me = 0.55 pmol/ml; p = 0.0382). At gestational age of 11–13 weeks, ET-1 level was significantly higher in the group with relapsed еPE (Me = 0.93 pmol/ml) than in control group (Me = 0.29 pmol/ml; p < 0.0001) and comparison group (Me = 0.42 pmol/ml; p = 0.0003). No significant changes in E-EVs (CD-144) level at various PС stages were observed, whereas in the study groups such parameters remained differed.Conclusion. Biological markers evidencing about systemic endothelial dysfunction/destruction – ET-1 and E-EVs (CD-144) in patients with previous ePE can be considered as predictive tests of disease relapse with an accuracy of 63.5 % and 83.0 % at the PС stage and 85.7 % and 94.2 % at gestational age of 11–13 weeks, respectively.