Laboratory Bench Research Articles

Barbed Dental Ti6Al4V Alloy Screw: Design and Bench Testing.

Dental implants are designed to replace a missing tooth. Implant stability is vital to achieving osseointegration and successful implantation. Although there are many implants available on the market, there is room for improvement. We describe a new dental implant with improved primary stability features. Lab bench test studies. We evaluated the new implant using static and flexion-compression fatigue tests with compression loads, 35 Ncm tightening torque, displacement control, 0.01 mm/s actuator movement speed, and 9-10 Hz load application frequency, obtaining a cyclic load diagram. We applied variable cyclic loadings of predetermined amplitude and recorded the number of cycles until failure. The test ended with implant failure (breakage or permanent deformation) or reaching five million cycles for each load. Mean stiffness was 1151.13 ± 133.62 SD N/mm, mean elastic limit force 463.94 ± 75.03 SD N, and displacement 0.52 ± 0.04 SD mm, at failure force 663.21 ± 54.23 SD N and displacement 1.56 ± 0.18 SD mm, fatigue load limit 132.6 ± 10.4 N, and maximum bending moment 729.3 ± 69.43 mm/N. The implant fatigue limit is satisfactory for incisor and canine teeth and between the values for premolars and molars for healthy patients. The system exceeds five million cycles when subjected to a 132.60 N load, ensuring long-lasting life against loads below the fatigue limit.

Design and Testing of a Smart Facemask for Respiratory Monitoring during Cycling Exercise

Given the importance of respiratory frequency (fR) as a valid marker of physical effort, there is a growing interest in developing wearable devices measuring fR in applied exercise settings. Biosensors measuring chest wall movements are attracting attention as they can be integrated into textiles, but their susceptibility to motion artefacts may limit their use in some sporting activities. Hence, there is a need to exploit sensors with signals minimally affected by motion artefacts. We present the design and testing of a smart facemask embedding a temperature biosensor for fR monitoring during cycling exercise. After laboratory bench tests, the proposed solution was tested on cyclists during a ramp incremental frequency test (RIFT) and high-intensity interval training (HIIT), both indoors and outdoors. A reference flowmeter was used to validate the fR extracted from the temperature respiratory signal. The smart facemask showed good performance, both at a breath-by-breath level (MAPE = 2.56% and 1.64% during RIFT and HIIT, respectively) and on 30 s average fR values (MAPE = 0.37% and 0.23% during RIFT and HIIT, respectively). Both accuracy and precision (MOD ± LOAs) were generally superior to those of other devices validated during exercise. These findings have important implications for exercise testing and management in different populations.

First Author Highlights

AnnouncementFirst Author HighlightsPublished Online:17 Mar 2023https://doi.org/10.1152/ajprenal.2023.324.3.AUMoreSectionsPDF (404 KB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat MOLLY BINGHAMSystems Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, United StatesFigure 1.Molly BinghamDownload figureDownload PowerPointMolly Bingham is a Postbaccalaureate Research Fellow at the National Cancer Institute. As an intern in the National Institute of Health’s 2021 Biomedical Engineering Summer Internship Program (led by Dr. Robert Lutz), she was mentored by Dr. Mark Knepper and studied circadian changes in gene expression in the kidney proximal tubule. Currently, Molly is investigating the tumor microenvironment in lung cancer under the mentorship of Dr. Chen Zhao. She hopes to pursue a career as a physician-scientist. When not in the laboratory or analyzing data, Molly enjoys cooking and spending time outdoors [Photo: Fig. 1].https://doi.org/10.1152/ajprenal.00231.2022JEROEN H. F. DE BAAIJDepartment of Physiology, Radboud University Medical Center, Nijmegen, The NetherlandsFigure 2.Jeroen de BaaijDownload figureDownload PowerPointJeroen de Baaij is an Associate Professor in renal physiology at the Radboud University Medical Center in Nijmegen, The Netherlands. His research focusses on the identification and characterization of new genes involved in renal magnesium reabsorption. Using a wide range of molecular, cellular, and physiological techniques, he examines new genes or new regulatory pathways in magnesium (re)absorption in the kidney. In his spare time, he writes about art and visits museums [Photo: Fig. 2].https://doi.org/10.1152/ajprenal.00298.2022KYLE DICKINSONDivision of Experimental Medicine, McGill University, Montreal, Quebec, CanadaFigure 3.Kyle DickinsonDownload figureDownload PowerPointKyle Dickinson is a researcher and laboratory manager in Dr. Julia Burnier’s laboratory at McGill University. He completed his PhD in Dr. Paul Goodyer’s laboratory in Experimental Medicine at McGill University. During his PhD, his research focused on understanding key signalling and DNA damage response pathways active in nephron progenitor cells during kidney development. His current research focuses on using liquid biopsy for cancer detection and monitoring treatment responses. Away from the laboratory bench, he enjoys sports, video games, and horror movies [Photo: Fig. 3].https://doi.org/10.1152/ajprenal.00207.2022MACKENZIE KUIDepartment of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United StatesFigure 4.Mackenzie KuiDownload figureDownload PowerPointMackenzie Kui is currently a third-year PhD student in Jennifer Pluznick’s laboratory at Johns Hopkins University. Mackenzie earned his Bachelor’s degree from the University of California-Santa Barbara, where he studied germline stem cell longevity in Drosophila diapause. After graduating, he worked as a Research Associate at City of Hope and then later at Oncovalent Therapeutics in small molecule discovery. Outside of the laboratory, Mackenzie enjoys climbing, volleyball, and swing dancing [Photo: Fig. 4].https://doi.org/10.1152/ajprenal.00272.2022ANDREW ORWICKDepartment of Pharmacology and Toxicology, University of Louisville, Louisville, KentuckyFigure 5.Andrew OrwickDownload figureDownload PowerPointAndrew Orwick is a PhD student in the Department of Pharmacology and Toxicology at the University of Louisville, mentored by Dr. Leah Siskind. He earned his PharmD from Sullivan University and practiced as a pharmacist for a number of years before deciding to go back to graduate school to obtain a PhD in the biomedical sciences. His PhD studies in chemotherapy-induced nephrotoxicity are supported by a National Institutes of Health National Institute of Diabetes and Digestive and Kidney Diseases F31 predoctoral fellowship. Andrew hopes to have his own research laboratory in academia one day. In his spare time, he enjoys playing soccer and spending time with his wife and two daughters [Photo: Fig. 5].https://doi.org/10.1152/ajprenal.00317.2022This article has no references to display. Download PDF Back to Top Next FiguresReferencesRelatedInformation Related ArticlesCircadian gene expression in mouse renal proximal tubule 01 Mar 2023American Journal of Physiology-Renal PhysiologyMagnesium reabsorption in the kidney 17 Feb 2023American Journal of Physiology-Renal PhysiologyWT1 regulates expression of DNA repair gene Neil3 during nephrogenesis 17 Feb 2023American Journal of Physiology-Renal PhysiologyThe transcription factor Foxi1 promotes expression of V-ATPase and Gpr116 in M-1 cells 17 Feb 2023American Journal of Physiology-Renal PhysiologyLung cancer-kidney cross talk induces kidney injury, interstitial fibrosis, and enhances cisplatin-induced nephrotoxicity 01 Mar 2023American Journal of Physiology-Renal Physiology More from this issue > Volume 324Issue 3March 2023Pages i-ii Crossmark Copyright & PermissionsCopyright © 2023 the American Physiological Society.https://doi.org/10.1152/ajprenal.2023.324.3.AUPubMed36929919History Published online 17 March 2023 Published in print 1 March 2023 Metrics

Mechanics of lumenless pacing lead strength during extraction procedures based on laboratory bench testing

With the advent of conduction system pacing, use of the Medtronic SelectSecure Model 3830 lead has increased substantially. However, with this increased use, the potential need for lead extraction also will increase. Lumenless lead construction requires an understanding of both applicable tensile forces as well as lead preparation techniques that can influence consistent extraction. The purpose of this study was to use bench testing methodologies to characterize the physical properties of lumenless leads and to describe related lead preparation methods that support known extraction techniques. Multiple 3830 lead preparation techniques, commonly used in extraction practices, were compared on the bench to assess rail strength (RS) in simple traction and use conditions with simulated scar. Retention of the IS1 connector vs severing the lead body preparation techniques were compared. Distal snare and rotational extraction tools were evaluated. The retained connector method provided higher RS compared to the modified cut lead method: mean 11.42 lbf (9.85-12.73 lbf) vs 8.51 lbf (1.66-14.32 lbf), respectively. Snare use distally did not significantly affect RS: mean 11.05 lbf (8.58-13.95 lbf). Lead damage occurred with the TightRail extraction tool at angles ≥90°, which could occur with right-sided implants. When extracting SelectSecure leads, the retained connector method to maintain cable engagement benefits preservation of the extraction RS. Limiting traction force to <10 lbf (4.5 kgf) and avoiding poor lead preparation methods are critical to consistent extraction. Femoral snaring does not change RS when needed and offers a method to regain lead rail in cases of distal cable fracture.

Газоприводная скважинная насосная установка для добычи нефти из наклонных и горизонтальных скважин

The design of a gas-driven downhole pumping unit for oil production from directional and horizontal wells has been developed. The unit has no rod string, the slide and pneumatic jack are located in the tubing string. Using these units with a compressed associated gas as a working fluid will allow, unlike the hydraulic pumps, avoiding complex surface equipment for preparing the working fluid, maintenance of which is rather labour-consuming, and increasing the reliable operation of slides and downhole pumping units as a whole. In the course of experimental study of the parameters of the proposed installation it was shown on a laboratory bench showed that the fluid feed increases in direct proportion to the rate from 0.6 to 3.6 m/min. There has been obtained an empirical dependence to determine the flow of a borehole pump depending on its geometric parameters, plunger stroke length, stroke speed and gas content in the produced oil. According to the estimated parameters of the developed gas-driven unit, the supply can reach 386 m3/day, which is comparable to the supply of hydraulic units in use.

Real-Time Power Control of Doubly Fed Induction Generator Using Dspace Hardware

Numerous studies have been undertaken to evaluate wind energy systems’ active and reactive power control, the energy produced, and their its link to distribution networks. This research makes a novel contribution to the discipline in this setting. The novelty of this work aims to design a new wind emulator and design a power control approach for a doubly fed induction generator (DFIG)-based wind system. A description of the system was provided first. Secondly, the control strategy was described in detail. Then, it was applied to both converters (machine and grid sides). Three stages were used to evaluate the control solution: (1) a MATLAB/Simulink simulation to validate the reference’s persistence (for both real and step wind speeds) and the system’s robustness, (2) implementation in real-time on a dSPACE-DS1104 board linked to an experimental laboratory bench, and (3) overlapped comparison experimental and simulated data to conduct a thorough quantitative and qualitative analysis using the root-mean-square error measures. The simulation and experimental findings demonstrate that the suggested model is valid and presents an excellent correlation between experimental and simulated results regarding wind speed variation.

Modification of sisal cellulose (Agave sisalana) with poly(vinyl alcohol) and its evaluation in a water-heavy oil system

Cellulose is a natural, non-toxic and biodegradable polymer that can have its structure modified to give it the desired properties. This study aimed to modify sisal cellulose (Agave sisalana) from its xanthate with poly (vinyl alcohol) (PVA) and to evaluate its viscosifying action on the flow behavior of a water-heavy oil system for petroleum production, on a laboratory bench. The modified process was carried out by graphitization and monitored by FTIR. The viscosifying potential was evaluated by measuring intrinsic degrees and the action of modified sisal cellulose (CSM) in the water-heavy oil system was gradually evaluated, at temperatures of 25°C and 60°C, using a brookfield viscometer. The FTIR spectra confirmed the modification by the appearance of the wavenumber band 880 cm-1, indicating the occurrence of the substitution reaction of [–OH] groups of the C-6 of the cellulose structure. The rate of the water-heavy oil system with the CSM was equal to the graduation of the heavy oil, with the same flow activation energy (Ea) in the amount of 66,509 kJ/mol, which gave potential use of the CSM in the correction of the profile of result of the system under study

Sensorless Current Pulsation Compensation in a Hybrid Energy Storage

This paper presents a dual active bridge DC/DC converter used as an AC current compensator in a hybrid energy storage application. The AC current in the DC link appears when a three-phase, four-wire inverter operates with unbalanced output currents—for example, when trying to compensate for grid voltage unbalance. This AC current has adverse effects on the operation of the electrochemical energy storage, and it should be compensated. To achieve this, a compensator is introduced into the DC link circuit of the inverter—a DC/DC converter with a capacitor bank. The DC/DC converter is responsible for compensating the AC pulsation by creating its own pulsation with the opposite phase. In the paper, the genesis of this pulsation is explained, and a compensation circuit is proposed along with a sensorless compensation algorithm. The algorithm is based on symmetrical decomposition and is used to generate a reference signal for the compensator. The numerical analysis of the algorithm is presented, and the operation of the compensator is verified on the laboratory bench.

Studying the thermal characteristics and effectiveness of structural fire proofing made of PROSASK Firepanel cement boards by means of reproducing the high-temperature effect

Introduction.The application of PROZASK fire-retardant panels demonstrates an option for and the expediency of a comprehensive study of fire proofing characteristics.Goals and objectives.The mission of this research project is to (1) obtain the results of experimental studies of fireproofing panels, containing the cement binder, (2) determine their fire proofing efficiency, using the radiant heating test bench that reproduces pre-set modes of high-temperature exposure, and (2) analyze the testing results using the method of mathematical modelling of temperature fields inside fireproof structures.Methods.Standardized laboratory techniques were used to clarify the thermal-physical characteristics of boards at relatively low temperatures. Their fire proofing efficiency was evaluated in the course of additional testing of specimens using the radiant heating test bench. A reliable and relatively uncomplicated method and programme for calculating unsteady temperature fields in fireproof structures were used to conduct the thermal analysis and generalization of experimental results. The authors summarized the results of standardized tests, conducted in a fire furnace, to determine the flame-retardant efficiency of PROZASK Firepanel boards and the fire-resistance of the full-size structures they protect.Results.Values of specific heat capacity and the thermal conductivity coefficient of boards, tested using laboratory benches at relatively low temperatures, were verified. The results of thermocouple measurements, taken during the testing of specimens with the help of the radiant heating bench in standard and hydrocarbon temperature modes, were obtained. The processing of these results, using thermal engineering analysis, allowed determining the values of the thermal conductivity coefficient in the range of operating temperatures. The influence of moisture, contained in the boards, on their fire protection efficiency was evaluated. Comparison between the results of calculations and tests, conducted in the fire furnaces, showed the practical usability of the obtained characteristics of boards and the thermo-engineering analysis used to (1) clarify the fire-proofing efficiency and the design developed using PROZASK Firepanels and (2) evaluate the fire-resistance of the constructions they protect.Conclusions.The presented integrated studies generated a considerable amount of important information, required to prognosticate the fire proofing properties and the fire-resistance of constructions that contain PROZASK Firepanels. The role of additional testing of specimens using a radiant heating test bench and the effectiveness of thermal-engineering calculations as a tool for assessing the parameters of fire proofing and the fire resistance of structures are demonstrated.

MSFP: Undergraduate 'collaborate from home' research in macromolecular structure and function.

When the COVID-19 crisis shut down most undergraduate research opportunities, we developed an online, remote, computer-based Research Experiences for Undergraduates on the topic of Macromolecular Structure and Function that was funded by the USA National Science Foundation. The REU provided a mentored research experience and training in professional skills to assist the participants in pursuing a degree and future career in STEM. This fully virtual project involved faculty at four geographically-distributed institutions specializing in diverse but complementary approaches to study macromolecular structure and function. Importantly, its online “collaborate-from-home” format made it accessible to students during the pandemic to participate fully in the research, professional development, and other activities of the program. This project can also serve as an example for future remote, online projects that would especially be helpful for students who might not have access to these kinds of programs at their universities, might not be able to travel to a university for a summer program, have physical challenges that make it difficult for them to work at a lab bench, or students whose research opportunities are limited due to political unrest. We think our experiences with our MSFP REU program would provide helpful information for members of the BPS to set up similar programs to serve additional students.

Assessment of Changes in the Abrasiveness of Solid Particles in Hydraulic Mixtures Pumped with ESPs

The statistics of using downhole electric submersible pump (ESP) units in the oil fields of Eurasia show that hydroabrasive wear is a common cause of ESP emergency failures. The authors of this study theoretically and experimentally investigated the peculiarities of water–abrasive wear of ESP components. The research methodology and construction of the laboratory bench are described, and the results of experimental studies of determination of changes in the abrasivity index of impurity particles contained in the mixture pumped with the working stages of an ESP section are given. It is shown that large particles of mechanical impurities in contact with the metal of the working stages are subjected to intensive grinding of up to 0.25…0.3 mm; after that, particle size remains practically unchanged. An increased abrasiveness index of mechanical impurities causes an increase in the intensity of wear of interstage seals along the flow of a water–abrasive mixture (from the inlet to the outlet of the pumping section). Based on the obtained results, recommendations for selection of devices for formation-fluid cleaning during development and operation of oil wells are given. The relevance of work on improving the design of interstage seals of ESP units is substantiated.

Development of the security and fire system training stand for student training

The article is devoted to the organization of the educational process using a specialized laboratory stand of security and fire systems. The main purpose of the paper is to form professional competencies of students in the field of security and safety systems. The paper describes in detail the structure and components of the laboratory stand, emphasizing the importance of its key elements - the control panel "Astra-812 Pro" and a variety of detectors. This allows students to practically apply theoretical knowledge, studying the functioning and interaction of various components of the security and fire system. The article also presents schemes of connection of detectors to the expander, allowing students to more deeply understand the technical side of the process. The steps of the bench training are disclosed to support step-by-step, sequential learning. The study emphasizes the effectiveness of the proposed learning system, which involves direct student interaction with hands-on equipment. The findings confirm the significance of using such training stands in modern higher professional education, emphasizing their contribution to the formation of the necessary professional competencies in future specialists in the field of safety and security. Scientific novelty of the work consists in the development and application of a specialized training stand for teaching students to work with security and fire systems. This allows students to get direct experience of interaction with the equipment, deepen their understanding of the technical aspects of the systems operation and improve their practical skills. The work also contributes to research on educational approaches in the field of safety and security by proposing an effective teaching methodology through the use of a laboratory bench. This provides a platform for further research and development in this area that can broaden and deepen the educational opportunities in the field.

Study of a Cutting Fluid Application System Adaptation on a Bench Milling Machine for an Academic Laboratory Environment

Abstract: Cutting fluid is a resource that can benefit machining, improving the service life, surface, and dimensional qualities of cutting tools. For the operation of a basic cutting fluid application system, it is necessary to consider the components that store, filter, and induce the flow of the cutting fluid. Some essential components are the reservoir, the filter, and the pump. Aiming to provide better machining conditions, this study presented the proposal for designing and manufacturing a cutting fluid application system for an academic laboratory's bench drill/milling machine. The experimental research characterized the study methodology, in which the system was built with the least possible resources. The main result showed that the system achieved the proposed objective. For pump selection, a system of equations was developed in Microsoft Excel software, which indicated a pressure variation in the flow system of approximately 15 kPa. After the three-dimensional modeling, a script for the manufacture and assembly of the system components was prepared, involving the processes of forming, machining and welding. Adaptations were made to the machine tool, such as the insertion of a limit switch that reduced the longitudinal displacement of the work table by 150 mm. An electronic command system was inserted to control the cutting fluid flow. In the testing phase, positive aspects were observed (reservoir position, absence of leaks, cutting fluid flow, among others) and negative aspects (cutting fluid return paths). Some further improvements proved possible, especially on a machine not designed to have a cutting fluid system.

Numerical and experimental-aided framework based on TPA for acoustic contributions of individual transfer paths on a vehicle door in the slamming event

The luxury sound quality of a vehicle door in the slamming event will increase consumers’ willingness to purchase the vehicle, thus its detailed investigation is a crucial consequence for the advancement of the automobile industry. This paper proposes a numerical and experimental approach on a transfer path analysis (TPA) to determine the sound quality for the individual transfer paths of the vehicle door in the slamming event. In our previous investigations, the transient impact loads of the vehicle door in the slamming event had been determined based upon lab experiment and bench test. These transient impact loads will be selected as input values for a numerical and experimental approach on the TPA. The noise transfer functions (NTFs) from the discretized path points to the driver’s ear are obtained by a numerical simulation technique. The sound pressure value at the driver’s ear is calculated and synthesized from the above transient impact loads and the NTFs and is verified by the sound pressure acquisition experiment. Then sound quality with objective evaluation is quantitively investigated utilizing five characteristic criterions: main impact time, low frequency duration, A-weighted sound pressure level, loudness, sharpness. Simultaneously, the subject evaluation is implemented to estimate the sound quality employing the laboratory-scale jury test. The back-propagation neural network (BPNN) improved via the genetic algorithm (GA) is suggested to appraise the mathematical relationship between the subjective and objective evaluation of the sound quality for the vehicle door slamming event. Finally, the built GA-BPNN model is applied to predict the subjective evaluation for the sound quality of the TPA. The transfer paths with a large contribution to the sound quality will be deemed to be suppressed objects in the subsequent analysis. This appraisal approach can be employed as a productive evaluation tool of the vehicle door slamming event for subsequent vibration and noise optimization.

Physical Modeling of the Drying Process Using Thermoelectric Heat Pump

A functional and technological scheme and a physical model of a convective thermoelectric dryer for vegetables, fruits, mushrooms, seeds, medicinal plants and other household materials have been developed. A laboratory bench has been prepared and studies of the thermal and electrical parameters of a thermoelectric dryer operating in a heat pump mode have been carried out. Experimental studies of the operating sample of the thermoelectric dryer have shown the high energy efficiency of the plant being developed.

Simulation of the structure of a multistory building with seismic isolation and the testing technique on a laboratory bench under dynamic ((seismic) impacts)

The article presents the main provisions of modeling multi-story buildings with seismic isolation, the characteristics of the seismic isolation device, structural elements and materials, the methodology for conducting experimental studies on a laboratory vibro-stand under dynamic (seismic) effects and the results of the modeling.

Результаты исследования горения твердых веществ в закрытом объеме

The paper presents the results of laboratory experiments to study the parameters of the gas environment during the combustion of wood, rubber and plastic under conditions that exclude oxygen access to the reaction area. A laboratory bench has been developed to create the conditions. Graphs of temperature changes and reduction of light transmission of combustion products accumulated in the upper part of the combustion chamber layer have been obtained. Changes of the controlled parameters are analysed and correlation dependences between them are obtained. The results obtained can be used as estimates for building prediction models of fire development in enclosed storage rooms, as well as for assessing the fire hazard of substances when burning in an enclosed volume.

ВИВЧЕННЯ ВИМІРЮВАННЯ ТЕМПЕРАТУРИ В ЗОНІ РІЗАННЯ ІЗ ЗАСТОСУВАННЯМ АНІМАЦІЙНОГО СИМУЛЯТОРА

The temperature that occurs in the cutting zone significantly affects the wear and stability of the tool, the quality of the surface of the part and the accuracy of processing. Therefore, the study of thermal phenomena is an important task.Nowadays, the use of a simulation software product in the study of various academic disciplines is relevant.For a better understanding of the work process of various phenomena, computers and software products are used, which give the educational process a more intensive and interactive content.When performing laboratory work "Measurement of temperature in the cutting zone" it is suggested to use advanced information technologies, namely an animation simulator.The purpose of the article is to propose the use of a simulator for measuring the temperature in the cutting zone in the educational process.The “SimulatorTEMPERATURE.exe” file is launched. “Menu” appears on the screen. After getting acquainted with the main parts of the machine, they begin to set up the laboratory bench for the specified cutting modes: spindle speed, feed, cutting depth. In the process of simulating processing, indicators are removed from the device. The results are recorded in the work protocol. According to the calibration schedule, the value of the temperature at the specified processing mode is found. In the future, the machine is adjusted for other processing modes. After the end of all experiments, the results are processed and the necessary conclusions are drawn.The educational simulator, which is proposed when performing laboratory work on the study of the temperature in the cutting zone, will allow a better understanding of the process, and is also more visual.The article is a scientific and methodological publication.

Formation of Loads on the Interstation Tunnels at Deep Grounding Subway Stations in the Geotechnical Conditions of St. Petersburg

One of the unresolved issues in the design of subway structures is the formation of loads on the interstation tunnels near subway stations on deep ground. There are three ways to determine the pattern of load changes from the full weight of the uppers soil above the station tunnel to the weight of the soil in the collapse vault above the interstation tunnel: mathematical modeling, full-scale field experiment or physical modeling. In the article, the authors analyze this problem and propose to solve it by physical modeling using the method of equivalent materials. The laboratory bench simulates the massif of the Upper Kotlin hard clays, the interface section of the station tunnel and the interstation tunnel, as well as the load from the overlying quaternary soils. In the next stages of the experiment, it is planned to simulate tunneling and take readings from the contact pressure sensors on the tunnel lining. The results of the research will allow us to proceed to a reasonable mathematical modeling of the law of distribution of loads, as well as perform adequate verification of the subsequent mathematical models.

The Development of a Laboratory Bench for Predicting the Quality of Processed Thermoplasts and Operating Characteristics of the Extruder

The Development of a Laboratory Bench for Predicting the Quality of Processed Thermoplasts and Operating Characteristics of the Extruder