New interaction solutions of the similarity reduction for the integrable (2+1)-dimensional Boussinesq equation

The nonlocal symmetry of the new integrable [Formula: see text]-dimensional Boussinesq equation is studied by the standard truncated Painlevé expansion. This nonlocal symmetry can be localized to the Lie point symmetry of the prolonged system by introducing two auxiliary dependent variables. The corresponding finite symmetry transformation and similarity reduction related to the nonlocal symmetry of the new integrable [Formula: see text]-dimensional Boussinesq equation are studied. The rational solution, the triangle solution, two solitoff-interaction solution and the soliton–cnoidal interaction solutions for the new [Formula: see text]-dimensional Boussinesq equation are presented analytically and graphically by selecting the proper arbitrary constants.

The German-Polish Tax Problems of Cross-Border Workers in the COVID-19 Pandemic – When the Remedy is Worse than the Problem

The article pertains to the tax issues arising from the COVID-19 pandemic in respect of cross-border workers. The main issue is the impact of the restriction in cross-border movements during the pandemic on the determination of the place of work. The authors refer to two situations. The first is when a Polish worker employed by a Polish employer and working abroad cannot return to Poland. The second is when he or she performs work at home in Poland instead of at the normal place of work abroad. The authors consider the legal fiction of carrying out work in the place where it would have been done before the pandemic as a rational solution. However, they are strongly critical of the introduction of such solution via the Mutual Agreement.

A probabilistic approach to the dynamic cut-off grade assessment

Cut-off grade is an important conditioning parameter that determines the quantity and quality of recoverable reserves and development efficiency. Today, Russian mining companies operate with certified quality requirements. By setting permanent quality requirements, the government seeks to prevent depletion of reserves, reduced production during periods of falling prices, and decreased budget revenues, expressing the interests of all members of society. But to what extent do the permanent quality requirements protect the interests of the state? The answer to this question is ambiguous and does not lie on the surface. The State Commission for Reserves and domestic researchers are working to find a rational solution to the problem of quality requirements. One solution is dynamic quality requirements. The effectiveness of their application has been proven for individual mining companies, but it is incorrect to transfer these conclusions to the entire mineral resource base of the country. This article presents a new approach to determining the dynamic cut-off grade, which varies depending on the price of minerals. The dynamic cut-off grade is proposed to be determined based on the indicators of constant requirements to the quality of exploration work, using the maximum allowable costs in the region. The approach allows to calculate the effect of the introduction of dynamic cut-off grade in the practice of subsurface use for the state (in the form of the amount of taxes received) and for subsoil users (in the form of the amount of income). For a group of gold-bearing deposits with open-pit mining method, it was established that the development of reserves using dynamic values of the cut-off grade in periods of price changes ensures compliance with the interests of the state and subsoil users.

Dynamic Bus Scheduling of Multiple Routes Based on Joint Optimization of Departure Time and Speed

Dynamic bus scheduling is a rational solution to the urban traffic congestion problem. Most previous studies have considered a single bus line, and research on multiple bus lines remains limited. Departure schedules have been typically planned by making separate decisions regarding departure times. In this study, a joint optimization model of the bus departure time and speed scheduling is constructed for multiple routes, and a coevolutionary algorithm (CEA) is developed with the objective function of minimizing the total waiting time of passengers. Six bus lines are selected in Shenyang, with several transfer stations between them, as a typical case. Experiments are then conducted for high-, medium-, and low-intensity case of smooth, increasing and decreasing passenger flow. The results indicate that combining the scheduling departure time and speed produces better performances than when using only scheduling departure time. The total passengers waiting time of the genetic algorithm (GA) group was reduced by approximately 25%–30% when compared to the fixed speed group. The total passengers waiting time of the CEA group can be reduced by approximately 17%–24% when compared to that in the GA group, which also holds true for a multisegment convex passenger flow. The feasibility and efficiency of the constructed algorithm were demonstrated experimentally.

A Dendritic Cell-Activating Rv1876 Protein Elicits Mycobacterium Bovis BCG-Prime Effect via Th1-Immune Response

The widely administered tuberculosis (TB) vaccine, Bacillus Calmette-Guerin (BCG), is the only licensed vaccine, but has highly variable efficiency against childhood and pulmonary TB. Therefore, the BCG prime-boost strategy is a rational solution for the development of new TB vaccines. Studies have shown that Mycobacterium tuberculosis (Mtb) culture filtrates contain proteins that have promising vaccine potential. In this study, Rv1876 bacterioferritin was identified from the culture filtrate fraction with strong immunoreactivity. Its immunobiological potential has not been reported previously. We found that recombinant Rv1876 protein induced dendritic cells’ (DCs) maturation by MAPK and NF-κB signaling activation, induced a T helper type 1 cell-immune response, and expanded the population of the effector/memory T cell. Boosting BCG with Rv1876 protein enhanced the BCG-primed Th1 immune response and reduced the bacterial load in the lung compared to those of BCG alone. Thus, Rv1876 is a good target for the prime-boost strategy.

Exploring the possibility of increasing the efficiency of the Earth remote sensing space system during modernization in the planned period

The paper considers the problem of complex optimization of the parameters of spacecraft and the space system for Earth remote sensing (ERS). The development (modernization) of equipment and technologies in the planned period is taken into account. The problem is formulated in a deterministic setting. The criterion for solving the task is the reduced total costs for the implementation of the ERS space system project during modernization in the planned period. When searching for a rational solution to the problem, its parametric decomposition is used. Variants of spacecraft modifications as part of the system and the program of modernization of the system are formed separately. The vector of variable parameters includes the parameters of the spacecraft modification and the system modernization program, i.e. the number of modifications of this spacecraft and the timing of their creation. The parameters of the ground segment and the base spacecraft are set. The study shows that the most rational approach to solving the problem is to construct a multi-level design research diagram in accordance with the structure of the system. A two-level design research model and a two-level coordinated optimization method are implemented, including a directed adaptation of the top-level design dependencies. The algorithm for solving the problem includes blocks for forming variants of the spacecraft modification, optimizing the modernization program, assessing the target efficiency, and determining the reduced total costs for the implementation of the system modernization program in the planning period. The possibility of increasing the efficiency of future ERS space systems is explored according to the results of solving the model problem. Using the model example, the parameters and the program of modernization of two alternative options for space systems of different altitudes located in sun-synchronous orbits are comprehensively assessed. The estimation of performance indicators of the considered variants of the systems is given. The assessment of technical and economic characteristics obtained on the basis of the model example can be used for a detailed analysis of the efficiency of future ERS space systems in order to predict their development and expand the field of application.

Discrete-Event Simulation of the Triangular Relations of the Components of the Working Process of a Dentist Doctor in Endodontic Manipulations

Today in modern dentistry one of the urgent tasks is to increase the level of productivity of the dentist, while maintaining his or her mental and physical health. To find a rational solution to this issue, much attention is paid to ergonomics, which is aimed at protecting the work of doctors, improving the efficiency and quality of their work, creating optimal working conditions for them, ensuring safety and comfort for patients, and developing the latest dental equipment. The purpose of the study is to describe the clinical and experimental forecasting of the influence of ergonomics derivatives of dentists on the result of endodontic manipulations. Materials and methods. The methods, which were used, are targeted research methods, in particular Rapid Entire Body Assessment and Rapid Upper Limb Assessment, software Tecnomatix Jack (Siemens), StatPlusPro for Windows. The subject of research: a sample of 32 dentists (17 male dentists) (53.13%) and 15 female dentists (46.88%), who provide dental care on the basis of the University Dental Clinic, as well as in within other clinical bases of the dental faculty of Uzhhorod National University. Results and discussion. Analyzing the final results of iatrogenic interventions, there is a direct impact of ergonomics, justified by the presence of proven relationships between the integrated quality indicator of dental rehabilitation and procedural-manual-associated components of the treatment process. Non-compliance with the basic principles of ergonomics during various dental manipulations is evidence of changes in the pathological nature of the musculoskeletal system of the dentist, but there is still lack of data on the impact of the above changes on quantitative and qualitative indicators of effectiveness and predictability of treatment. Considerable attention needs to be paid to the analysis of the influence of ergonomic features of dentists' work on the result of endodontic treatment of teeth and their post-endodontic restoration, taking into account the initial complexity of this type of manipulation. As this is significantly influenced by anatomical variations in the structure of the endodontic, limited visualization of the working field, the need to ensure mandatory isolation of the intervention and permanent control over the absence of contamination of endodontic structures during treatment, topographic features of individual teeth (molars, in particular), features and physical characteristics of mechanical (rotational) and manual endodontic instruments. Conclusion. Occurrence of complications arising from endodontic treatment directly affect the prognosis of the dentition as a complex biomechanical system of the dental apparatus in cases of further post-endodontic restoration of teeth by direct or indirect restorations, as well as when using them as supports for future crowns, and also removable and non-removable types of orthopedic structures. In cases of fixation of bridges on endodontically treated teeth, the emergence of iatrogenic-associated complications due to biomechanical and biological properties of the endodontic, is associated with a decrease in the prognosis of success and survival of the entire prosthetic structure as a whole, rather than one independent unit of the tooth. Based on this, predicting the risks associated with the development of errors and complications during endodontic treatment, as well as their minimization through the use of various types of preventive measures remains an important scientific and practical issue not only therapeutic but also orthopedic dentistry

Current standards for the conversion of flax varieties of fiber flax into conditional fiber with an assessment of the effectiveness of their use

The purpose of the research is the development of standards for the transfer of modern flax varieties of domestic and foreign selection into conventional fiber with an analysis of the problems arising in the course of their application and the proposal of ways for their rational solution. Methods. According to the current regulatory documentation using a special methodological program, the values of the following characteristics were determined: the total fiber yield, the yield and quality of long and short fiber from flax of various quality according to the results of control developments carried out in the conditions of flax processing enterprises and data from the State Variety Testing involved in the study of fiber flax varieties. Results and scope. The article presents the results of the development of standards for the conversion of different quality flax of 28 varieties of fiber flax into fiber, with their values given. It has been established that in order to obtain one ton of fiber from low grade flax trees (0.50–0.75), it is necessary to process 2.9–4.2 tonnes of flax trees; from flax trees of higher quality, with a value of 1.00 and more – 2.6–3.5 tons. Some issues related to the insufficient effectiveness of the use of translation standards in practice are considered. It is noted that when developing them, it is advisable to take into account the structure of the fiber contained in the stem material of a certain type with a division into fiber types: i. e., into long and short. At the same time, the accuracy of determining the cost of the produced fiber can increase by 20 %. It is also proposed to take into account the qualitative characteristics of long and short fibers, which can contribute to the correct orientation of an agricultural producer engaged in the cultivation of flax regarding the choice of fiber flax varieties with the most valuable economic characteristics. The reserve for increasing technical and economic indicators can be ~ 10 %. The need to develop a differentiated system is substantiated, which provides for taking into account the volume of fiber when converting into a conditional using standards specifically for each flax number in the range from 1.00 to 4.00. This may lead to an increase in the size of subsidies by 2.8–6.2 %. Scientific novelty. Standards have been developed for the conversion of flax of various quality into fiber of modern fiber flax varieties of both domestic and foreign origin, common in the flax-growing regions of the Russian Federation. The ways of increasing the efficiency of application of the established translation standards are proposed.

Soliton Molecules, Rational Positon Solution and Rogue Waves for the Extended Complex Modified KdV Equation

We consider the integrable extended complex modified Korteweg–de Vries equation, which is generalized modified KdV equation. The first part of the article considers the construction of solutions via the Darboux transformation. We obtain some exact solutions, such as soliton solution, soliton molecules, positon solution, rational positon solution, rational solution, periodic solution and rogue waves solution. The second part of the article analyzes the dynamics of rogue waves. By means of the numerical analysis, under the standard decomposition, we divide the rogue waves into three patterns: fundamental patterns, triangular patterns and ring patterns. For the fundamental patterns, we define the length and width of the rogue waves and discuss the effect of different parameters on rogue waves.

Аnalyzing existing systems of bridgework management on motorways

The existing system of bridgework management in our country does not satisfy the bridge branch as it is financially and organizationally integrated in the structure of the road organizations which allocate for operation of bridge constructions4÷10 % of all financing for road operation. This situation is explained by the fact that bridges are very capital-intensive and require in-depth preparation in the hierarchy of road organizations. Goal. The purpose of this work is to improve the system ofbridge management in the country based on the analysis of world experience. Methodology. The analysis of many bridge management systems in Europe and the United States may allow to find the most rational solution in terms of practical implementation, to improve the situation in the bridge industry – which is the transition from overhaul to preservation of structures in the first 15-20 years. Results. This preservation allows to extend their service life. During this period the repairs of road clothes (at the expense of capital repairs) should be carried out aiming to prevent from developing damages of reinforced concrete elements. Originality. The main feature of the improved system of bridgework management is ensured regulation of the process of bridges maintenance which would provide comfort for traffic and long-term safety of structure functioning. Practical value. To implement this system, it is necessary to divide the operation of roads and the operation of bridges into separate structures with separate funding.