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The growth in the number of communication satellites and the increase in antenna signal frequencies places higher demands on the accuracy and mass of reflectors. The accuracy of the reflector depends not only on its structure and materials but is also influenced by its mounting. In this paper, based on the rib-reinforced reflector designed by Bauman Moscow State Technical University, the effect of the reticulated shell mountings with different numbers of interlacing ribs in a shape of a circular truncated cone working in the geosynchronous orbit on the thermal deformation of the reflective surface is investigated by simulations using Siemens NX software. It is concluded that the desired deformation can be obtained when the number of t interlacing is 30. On thermal deformation, the effects of two weight reduction methods, namely reducing the width and thickness of ribs, were also investigated simultaneously. It is shown that reducing the thickness of ribs can achieve the target of mass reduction under the condition of ensuring the accuracy of the reflective surface. It is provided the basis for engineering calculations for practice.

The simulation model of the computational load balancing in a server complex using a balancing server is proposed. The server load balancing model was developed using MATLAB/Simulink/SimEvents/Stateflow tools. The SimEvents based model makes it possible to simulate the server complex as a queuing system and to take into account the sporadic occurrence of requests. The Stateflow based event-driven model simulates the system with a variable time delay in data transmission channels and simulates state transitions for servers. This discrete-event simulation model allows evaluating the possibility of rational use of computational resources and reducing the time of service. In addition, the model allows to investigate the effectiveness of load balancing systems at the stage of their development.

The issue of distribution of large amounts of information on server stations is researched. The analysis of existing methods for distributing data of heavily loaded web applications is carried out. A system for computing load distribution using a balancing server is proposed. A description of the software necessary for the functioning of the system and server management interface is provided.

The article deals with optimization issues in design of an automatic control system (ACS). The method of multicriteria optimization is presented, which combines simulation of ACS and optimization procedure based on a genetic algorithm and implemented by the MATLAB / Global Optimization Toolbox. The method of the generalized criterion composition based on the initial particular criteria is also proposed. The use of this generalized criterion makes it possible to reduce the complexity of determining the optimal parameters of the ACS and allows to take into account the constraints when searching for the optimal solution.

The method for parametric optimization of an automatic control system is proposed. The criterion for the quality of the functioning of the system includes control accuracy and control costs. The method takes into account the change in the operating conditions of the control object and the influence of random disturbances. A combination of a genetic algorithm procedure in MATLAB and system simulation in Simulink is proposed. Recommendations for choosing the optimal values of the system parameters are passed on to the operator of the technological process.

This article is about development and modeling of data distribution system through the server stations. An algorithm for selecting a server for downloading data based on fuzzy logic is proposed. A simulation model of a server complex created by MATLAB / Simulink / SimEvents software is presented. This model allows us to study the server complex as a system with discrete states based on the theory of queuing systems. Numerical experiments on the distribution of data among servers using different algorithms for selecting a server for user loading data were carried out. The advantage of the proposed approach to server selection based on fuzzy inference is shown. This advantage is expressed in reducing the length of queues in the system and increasing the number of serviced requests for data processing by servers.

In this article the issue of server stations status data processing for effective distribution of client data on the server stations in high load information systems is discussed. We have analyzed the existing methods for distributing data on server stations of high-loaded web applications, as well as solutions that improve the speed of data delivery to the user. Among the considered methods, we identified a prototype for development and proposed an approach to the design of data distribution systems. We have developed a model that describes the state of the servers, and proposed a structure for representing the parameters of the system. According to the obtained experimental data we have constructed graphs that reflect the dependence of server state parameters on time. In the future, we are planning to use this data about server states, as well as the data about end users (uploading or browsing files), in order to optimize server selection and ensure fast provision of information to the user.

One of the key problems in the design of nanosatellites is to provide a specified temperature range for the operation of electronic equipment. In structures of modern nanosatellites mainly used the elemental base of smartphones. To process a large amount of information, more advanced processors with high thermal power are required. The specified thermal mode of the on-board computer can be achieved using a remote heat removal system or by direct contact of the processor cover with the carbon fiber reinforced plastics (CFRP) body of the nanosatellite. Using a model of nanosatellite as an example, a thermal control system with miniature loop heat pipes and highly heat-conducting refrigerators-emitters is designed. The influence of the thermal conductivity coefficient in the reinforcement plane of the nanosatellite CFRP body on its temperature state in low Earth orbit is studied.

An important direction in the development of the shockproof devices for occupations associated with an increased risk of injury is reducing their overall size with the preservation the ability of energy absorption. The fixture protection of large joints, with the brace in the coils of an elastic-plastic material with shape memory effect, can effectively protect people from injury and can be used in the domain of occupational safety to reduce injuries by shocks or jolts. In innovative anti-shock device as elastic-plastic material applied equiatomic Titanium-Nickel alloy which has acceptable temperature phase transitions that is necessary to restore shape. As an experienced model first approximation was adopted shockproof device, having in its composition a bandage in coils of elastic-plastic material with shape memory effect and with electric contacts at the ends. This solution allows the punches to plastically deform with the absorption of the impact energy, and then recover the original shape, including at the expense of electric heating.

Following the discovery of circulating tumor cells (CTCs) in the peripheral blood of cancer patients, CTCs were initially postulated to hold promise as a valuable prognostic tool through liquid biopsy. However, a decade and a half of accumulated data have revealed significant complexities in the investigation of CTCs. A challenging aspect lies in the reduced expression or complete loss of key epithelial markers during the epithelial-mesenchymal transition (EMT). This likely hampers the identification of a pathogenetically significant subset of CTCs. Nevertheless, there is a growing body of evidence regarding the prognostic value of such molecules as CD24 expressing in the primary breast tumor. Herewith, the exact relevance of CD24 expression on CTCs remains unclear. We used two epithelial markers (EpCAM and cytokeratin 7/8) to assess the count of CTCs in 57 breast cancer patients, both with (M0 mts ) and without metastasis (M0) during the follow-up period, as well as in M1 breast cancer patients. However, the investigation of these epithelial markers proved ineffective in identifying cell population expressing different combinations of EpCAM and cytokeratin 7/8 with prognostic significance for breast cancer metastases. Surprisingly, we found CD24+ circulating cells (CCs) in peripheral blood of breast cancer patients which have no epithelial markers (EpCAM and cytokeratin 7/8) but was strongly associated with distant metastasis. Namely, the count of CD45-EpCAM-CK7/8-CD24+ N-cadherin—CCs was elevated in both groups of patients, those with existing metastasis and those who developed metastases during the follow-up period. Simultaneously, an elevation in these cell counts beyond the established threshold of 218.3 cells per 1 mL of blood in patients prior to any treatment predicted a 12-fold risk of metastases, along with a threefold decrease in distant metastasis-free survival over a 90-month follow-up period. The origin of CD45-EpCAM-CK7/8-CD24+ N-cadherin—CCs remains unclear. In our opinion their existence can be explained by two most probable hypotheses. These cells could exhibit a terminal EMT phenotype, or it might be immature cells originating from the bone marrow. Nonetheless, if this hypothesis holds true, it's worth noting that the mentioned CCs do not align with any of the recognized stages of monocyte or neutrophil maturation, primarily due to the presence of CD45 expression in the myeloid cells. The results suggest the presence in the peripheral blood of patients with metastasis (both during the follow-up period and prior to inclusion in the study) of a cell population with a currently unspecified origin, possibly arising from both myeloid and tumor sources, as confirmed by the presence of aneuploidy.