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In multi-mass systems, torsional vibration is a common and annoying phenomenon. Effective vibration suppression and robustness to wide-range parameter variations are essential for a sound motion system. However, most control methods focus on the primary resonance mode, and the high-order resonance modes are not actively treated in the control design, resulting in the control bandwidth not being high enough and limiting the control performance. This paper proposes a novel two-stage design scheme to realize a wideband control to improve control performance. First, a hybrid uncertainty model is tailored for multi-mass systems, which uses an equivalent and uncertain spring constant to describe the variation of the primary mode and a dynamic uncertainty to cover the other resonance modes. This hybrid model strikes a better balance between the model conservatism and the feasibility of a less conservative design. Then, the passivity of the parameter uncertainty is utilized to conduct a phase compensation on the nominal system. After the phase compensation, all uncertainties are converted into norm-bounded ones, and the robust performance design is carried out. This method is applied to vehicle drivetrain benches, and its superiority is validated through simulation comparisons and experiments on two typical types of drivetrain benches. • Hybrid model for multi-mass systems characterizes primary resonance and other modes. • Two-stage design method with phase-shaping achieves high performance robust control. • The method is applied to drivetrain benches, outperforming the conventional methods. [ABSTRACT FROM AUTHOR]

Modular multilevel converters (MMCs) have been utilized in solid-state transformers (SSTs). With the increasing demand in high-voltage power module in MMC-SST, press-pack IGBTs are very promising. The poly-ether-ether-ketone (PEEK) frame is utilized in the submodules of press-pack IGBT to withstand the high voltage. The electric field simulation in this paper reveals that electric field concentrates on the surface of the PEEK frame. Thus, the surface partial discharge characteristics under direct current (DC) voltage is investigated by the developed test bench. The results show that surface partial discharge model of PEEK sample has polarity effect. Under positive and negative polarity voltage, the average discharge quantity, maximum discharge quantity and discharge repetition rate of the PEEK sample all increase with the voltage amplitude. Moreover, the front time of the surface partial discharge waveform reaches 20 ns, and its frequency spectrum is concentrated in range of 10–20 MHz. [ABSTRACT FROM AUTHOR]

Safety, efficiency, and reliability are essential requirements for aero-engines. Timely and accurate diagnosis of engine faults enables effective planning of maintenance operations and reduces downtime. Although traditional physics-based methods perform well under controlled test bench scenarios, their effectiveness in handling very noisy data and missing values is limited, constraining their utility in real-world settings. To address these gaps, we propose a fusion autoencoder that combines physics-informed and pattern-informed techniques, augmented with a Beta-Variational Autoencoder learning backbone to enhance the robustness of the model. Additionally, a novel health index called the piecewise anomaly index is proposed that can detect and classify faults simultaneously. To evaluate the efficacy of the novel framework, we modified the New Commercial Modular Aero-Propulsion System Simulation (N-CMAPSS) dataset to simulate real-world scenarios and conducted experiments. The results show that the proposed method can detect faults earlier than common techniques, while also achieving accurate fault classification and degree determination with the new index. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we introduce a control method for the linear quadratic tracking (LQT) problem with zero steady-state error. This is achieved by augmenting the original system with an additional state representing the integrated error between the reference and actual outputs. One of the main contributions of this paper is the integration of a linear quadratic integral component into a general LQT framework. In this framework, the reference trajectories are generated using a linear exogenous system. During a simulative implementation for the specific real-world system of a car-in-the-loop (CiL) test bench, we assumed that the 'real' system was completely known. Therefore, for model-based control, we could have a perfect model identical to the 'real' system. It became clear that for CiL, stable solutions cannot be achieved with a controller designed with a perfect model of the 'real' system. On the contrary, we show that a model trained via Bayesian optimization (BO) can facilitate a much larger set of stable controllers. It exhibited an improved control performance for CiL. To the best of the authors' knowledge, this discovery is the first in the LQT-related literature, which is a further distinctive feature of this work. [ABSTRACT FROM AUTHOR]

This study is devoted to condition-based maintenance using vibration analysis. It proposes a numerical and experimental methodology to assist in the detection and vibratory monitoring of chipping faults on gear teeth. The aim of this work is to model the dynamic behavior of the gear link and to treat the vibration behavior of gear flaws theoretically and experimentally. This article is going to study the case of a breast gear, a defect located on the wheel, another defect on the pinion and the wheel and the insufficient center distance defect based on experiments carried out on a test bench manufactured in the laboratory. [ABSTRACT FROM AUTHOR]

Using a newly developed flow test bench, several charge configurations were analyzed to quantify the influence of the charge configuration in the mold in sheet molding compound (SMC) manufacturing. A test bench was developed to satisfy the industrial needs for the incoming goods inspection as well as the need for the flow characterization of rheological models in the simulation. The test setup has a cylindrical opening for the charge placement, from where the material is pressed into a thin flow channel, forcing the material to reorient. A comparison was performed by juxtaposing the resulting compression pressure recorded during the process. The charge for this test series, placed into the cylindrical opening, has two basal configurations, one consisting of a stack of disks, and the second in a rectangular sheet rolled up into a spiral. Six charge variations were tested in total. The amount of material, the batch, the layering and the production direction of the sheet proved to have a significant influence on the necessary compression pressure. Guidelines about the recommended charge configurations could be derived for optimized production settings, such as a reduction in the compression pressure and modifications to the charge. [ABSTRACT FROM AUTHOR]

Differential evolution algorithm is a very powerful and recently proposed evolutionary algorithm. Generally, only a mutation operator and predefined parameter values of differential evolution algorithm are utilized to solve various optimization problems, which limits the performance of the algorithm. In this paper, six commonly used mutation operators are divided into three categories according to their own features. A mutation pool is established based on the three categories. A parameter pool with three predefined values is designed. During evolution, three mutation operators are randomly chosen from the three categories, and three parameter values are also randomly selected from the parameter pool. The three groups of mutation operators and parameter values are employed to produce trial vectors. The proposed algorithm makes good use of different mutation operators. Three recently proposed differential evolution variants and three non-differential evolution algorithms are used to make comparisons on the 29 testing functions from CEC. The experimental results have demonstrated that the proposed algorithm is very competitive. The proposed algorithm is utilized to solve three real applications, and the results are superior. [ABSTRACT FROM AUTHOR]

The objective of this work is to analyze and compare AC microgrid (ACMG) solutions to introduce the topic to new researchers. The methodology used to achieve this goal is a systematic literature review using five questions: (1) How have ACMGs evolved in five years? (2) What are the standards for ACMGs? (3) What are the different schemes for connecting MGs to the utility grid? (4) What are the different control schemes in ACMGs? (5) What is an appropriate way to compare results when working with ACMGs? The articles were published in Q1/Q2 journals as based on either the Scimago Journal Rank (SJR) and/or the Journal Citation Report (JCR) between 2018 and 2022 and were from three databases: (1) Web of Science (WoS), (2) Scopus, and (3) IEEE Xplore. Publications not describing pure ACMGs, review papers, publications not related to the questions, and papers describing work that did not meet a quality assessment were excluded, resulting in 34 articles being included in this review. Results show: (1) the energy sources and AC bus nature of microgrids over five years, (2) the identification and quantification of cited standards for microgrids, (3) the pros and cons of different schemes for connecting an AC microgrid to the main grid, (4) the control schemes, classified in a hierarchical control structure, and (5) the simulation tools and experimental benches used in microgrids. Most studies considered a generic energy source and a low-voltage three-phase AC bus, 16 standards were found, and the most cited standard was IEEE Standard 1547. The most common connection scheme to the utility grid was a direct connection, most of the works proposed a modification to a hierarchical control system scheme, and the most common simulation tool was MATLAB. The preferred experimental setup consisted of parallel inverters for testing a control scheme, a prototype when proposing a power electronic system, and a laboratory microgrid for testing fault detection methods. [ABSTRACT FROM AUTHOR]

This work proposes a low-cost and easy-to-implement solution for a remote voltage-sensing circuitry that can be used to ensure stability and good voltage regulation in applications with power supplies driving currents over long paths. The circuitry is implemented with general-purpose electronic components and is provided as an external feature to be attached to power supplies without remote sensing. To demonstrate its capabilities, a test bench was put together alongside a power supply module which has local sensing only. With the test bench, the output voltage from the power supply was delivered in various scenarios to an electronic load. Multiple parameters were monitored in order to assess the power supply performance to which the proposed remote voltage-sensing circuitry is attached. The measurements include stability and transient response tests, and the results were compared with the ones obtained with the standard local sensing. The tests reveal that the power supply module kept its output voltage stable with less than +/−10% voltage variation, and the average transient recovery time was less than 100 µs. The results are given for two different output voltage values of 1.2 V and 3.3 V and at high current capabilities of 3.5 A. [ABSTRACT FROM AUTHOR]

To address the issues of poor positioning accuracy, low supply efficiency and inadequate adaptability for different tray specifications of the existing seedling tray conveying device, a dual-axis positioning tray conveying device was developed, which can accommodate seedling trays ranging from 21 to 288 holes. A dual-sensor positioning algorithm and variable displacement positioning method were proposed to increase the efficiency, ensuring precise initial positioning and intermittent movements both along the seedling conveyance (X-axis) and platform movement (Y-axis). The system utilizes a precise positioning servo-control system with three-closed-loop controls and a PID algorithm enhanced through simulation to refine seedling positioning accuracy. Experiments with nine different tray specifications were conducted on a step-controlled platform to test suitability, validating the performance of the initial positioning and intermittent transport in both the X and Y directions. On the X-axis, the initial positioning deviation of the seedling tray was up to 1.34 mm and the maximum deviation in the intermission conveying was 0.85 mm. Comparatively, the deviation on the Y-axis was smaller, with the initial positioning deviation up to 0.99 mm and the intermission moving deviation up to 0.98 mm. These results demonstrate that the designed device meets the requirements for precise transport, providing essential technological foundations for seedling tray transport and retrieval steps in fully automated transplanting machines. [ABSTRACT FROM AUTHOR]

Inspired by the maxillary mouthparts of longicorn beetles, four types of bionic cutters were designed in this research to address the prevalent issues of high cutting resistance and severe stubble damage encountered during alfalfa harvesting. Finite element simulation was utilized to assess the structural integrity and cutting performance of these bionic cutters. Additionally, bench tests were conducted on a homemade stem-cutting force measurement and control rig to evaluate their effectiveness. The results indicated: (1) the bionic cutters achieved a reduction in maximum equivalent force ranging from 20.9% to 49.2% and a decrease in maximum deformation from 31.4% to 64.1% compared to conventional cutters; (2) the maximum cutting resistance of alfalfa stems was reduced by 28.6%, 43.9%, 52.4%, and 38.6%, significantly enhancing the flatness of the cut surfaces; (3) orthogonal bench tests demonstrated that the type of cutter and the slip-cutting angle significantly influenced the maximum cutting resistance of the stems (p < 0.01), with the optimal configuration being bionic cutter c, a slip-cutting angle of 10°, and a rotational speed of 2600 rpm. In conclusion, bionic cutters demonstrate substantial advantages in reducing maximum cutting resistance and improving the flatness of alfalfa stubble, suggesting their potential for widespread application and adoption. [ABSTRACT FROM AUTHOR]

High-speed and precision planting was employed to improve the yields of soybean seeds. However, most mechanical seed metering devices had a lower quality index under high-speed. In this study, a high-speed and precision metering device with gradient-feeding (GF) and control-seed (CS) for soybean planting was designed to improve the quality index at high speeds. GF was designed to make soybean seeds rapidly enter seed cells. CS prevented soybean seed that was to be released from being cleared during the clearing stage. Firstly, the range of working parameters of it was determined by theoretical analysis, which included the angle of guiding-slope (α), the angle of seed-control (θ), and mutation height (ΔH). Then, orthogonal center combination tests with three-factor and five-level were carried out to determine the corresponding quality index and miss index with different working parameters. The optimal working parameters were determined by regression equations between the quality index and the miss index. The high-speed and precision metering device with GF and CS was thus manufactured based on these optimal working parameters. The simulation test and bench test of it were carried out with different forward speeds of the planter. The results showed that the optimal angle of α, θ, ΔH were 18.06°, 136.67°, and 2.77 mm, respectively. In the bench test, all quality indices were higher than 95.00%, and all miss indices were lower than 3.00% when the forward speed of the planter was 4-16 km/h. The results of the bench test were consistent with the results of the simulation test, with an average relative error of 2.33%. High-speed and precision metering device with gradient-feeding (GF) and control-seed (CS) can realize precision planting at high speeds. [ABSTRACT FROM AUTHOR]

ezSingleCell is an interactive and easy-to-use application for analysing various single-cell and spatial omics data types without requiring prior programing knowledge. It combines the best-performing publicly available methods for in-depth data analysis, integration, and interactive data visualization. ezSingleCell consists of five modules, each designed to be a comprehensive workflow for one data type or task. In addition, ezSingleCell allows crosstalk between different modules within a unified interface. Acceptable input data can be in a variety of formats while the output consists of publication ready figures and tables. In-depth manuals and video tutorials are available to guide users on the analysis workflows and parameter adjustments to suit their study aims. ezSingleCell's streamlined interface can analyse a standard scRNA-seq dataset of 3000 cells in less than five minutes. ezSingleCell is available in two forms: an installation-free web application (https://immunesinglecell.org/ezsc/) or a software package with a shinyApp interface (https://github.com/JinmiaoChenLab/ezSingleCell2) for offline analysis. ezSingleCell is an interactive and user-friendly application for the analysis of single-cell and spatial omics data, without the need for programming expertise. Here, authors integrated top-performing publicly available methods to enable comprehensive data analysis and interactive visualisation. [ABSTRACT FROM AUTHOR]

The etiology of gastrointestinal (GI) diseases is intricate and multifactorial, encompassing complex interactions between genetic predisposition and gut microbiota. The cell fate change, immune function regulation, and microenvironment composition in diseased tissues are governed by microorganisms and mutated genes either independently or through synergistic interactions. A comprehensive understanding of GI disease etiology is imperative for developing precise prevention and treatment strategies. However, the existing models used for studying the microenvironment in GI diseases—whether cancer cell lines or mouse models—exhibit significant limitations, which leads to the prosperity of organoids models. This review first describes the development history of organoids models, followed by a detailed demonstration of organoids application from bench to clinic. As for bench utilization, we present a layer‐by‐layer elucidation of organoid simulation on host–microbial interactions, as well as the application in molecular mechanism analysis. As for clinical adhibition, we provide a generalized interpretation of organoid application in GI disease simulation from inflammatory disorders to malignancy diseases, as well as in GI disease treatment including drug screening, immunotherapy, and microbial‐targeting and screening treatment. This review draws a comprehensive and systematical depiction of organoids models, providing a novel insight into the utilization of organoids models from bench to clinic. [ABSTRACT FROM AUTHOR]

Airdeck blasting is a promising technique for improved blast efficiency, reducing explosive consumption, and enhancing fragmentation. Nevertheless, it lacks widespread adoption due to design guideline gaps and differing opinions on air deck placement. This study offers technical guidance based on field experiments to optimise air deck blasting. Full-scale blast experiments were conducted at four distinct limestone benches to evaluate the efficacy of air deck implementation. At Bench-1, experiments were performed using conventional blasting (with full-column charge) and air decks at three strategic air deck positions (i.e., top, mid, and bottom) within blast holes at a selected quarry site. For Benches 2 and 3, comparative fragmentation analyses were conducted between conventional blasts and those utilising air decks positioned in the middle of the explosive column. Furthermore, the impact of multiple mid-air decks within explosive columns was also evaluated at Bench-4. A comparison of blast fragmentation results revealed that fragments obtained through the air decking technique surpassed those from the full-column charge, regardless of air deck placement. Among the tested air deck positions, the single air deck positioned at the middle of the explosive column yielded superior fragmentation results than other locations. In addition, this technique showed a reduction in explosive charge, back break, and toe-related issues. [ABSTRACT FROM AUTHOR]

In order to solve the traditional single-spiral fertilizer discharger issue of the fluctuation of fertilizer-discharge flow and the problem of precise fertilizer discharge, the innovative design of a cantilevered oblique placement of a fertilizer-discharging spiral structure in the form of an inclined spiral fertilizer discharger was realized, in which, through the fertilizer spiral's full end-filled extrusion, uniform delivery of the discharge was achieved. Discrete element simulation was used to compare the fertilizer-discharge characteristics of inclined and traditional single-spiral fertilizer dischargers, and the results proved that the inclined spiral fertilizer discharger effectively reduced the fluctuation of the fertilizer-discharge flow rate. Through a theoretical analysis preformed to determine the theoretical fertilizer discharge and the main parameters affecting the uniformity of fertilizer discharge, we identified the tilting angle of the fertilizer discharger (θ) and the distance from the termination spiral blade to the fertilizer outlet (l). A two-factor, five-level quadratic generalized rotary combination experiment was conducted with two parameters (θ and l) as the experiment factors and the variation coefficient of fertilizer-discharge uniformity (σ) as the experiment indicator. The experimental results showed that for σ, θ was a highly significant effect, l was a significant effect, and σ was less than 8.5%; when θ was 35.02° and l was 16.87 mm, the fertilizer-discharge performance was better. A bench experiment was used to compare the traditional and inclined spiral fertilizer dischargers, and the results showed that the relative error of the variation coefficient between the bench and the simulation experiment under this combination was 2.28%. And compared with the traditional spiral fertilizer discharger's σ average increase of 80.79%, the effect of fertilizer discharge was better than the traditional spiral fertilizer discharger. A fertilizer application controller was developed, and the bench performance was tested based on the measured fertilizer-discharge flow rate fitting equation of this combined inclined spiral fertilizer discharger. The results show that the electronically controlled inclined spiral fertilizer discharger has an average deviation of 3.12% from the preset value, which can be used to regulate the flow of fertilizer discharged through the fertilizer controller to realize precise fertilizer application, and this study can provide a reference for the optimal design of the spiral fertilizer discharger. [ABSTRACT FROM AUTHOR]

Copyright of Revista Educación en Ingeniería is the property of Asociacion Colombiana de Facultades de Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to the increasing complexity of vehicle software, it is becoming increasingly difficult to comprehensively test all requirements. This inevitably means that alternative test methods, e.g., simulation-based methods, must be used more frequently. However, the challenge involves identifying appropriate requirements that can be technically tested in a simulation environment initially. The present work is aimed at evaluation and optimization of the effectiveness of software-in-the-loop (SiL) simulations in the testing process of vehicle software. The focus is on supporting the testing process by shifting specific test cases from hardware-in-the-loop (HiL) test benches to SiL-based simulations. For this purpose, a systematic approach was developed to analyze and categorize requirements, enabling precise and efficient allocation of test cases. Furthermore, a detailed review and recommendation for improving the ProSTEP iViP standard for virtual electronic control units (vECU) was carried out. The developed matrix associates the defined requirement clusters with different classifications of vECUs, facilitating the identification of suitable test environment types for conducting specific test cases. By assigning test cases to appropriate vECU levels, the testing processes can be targeted and cost-optimized. Finally, the theoretical results were evaluated in an SiL simulation environment. It was observed that a significant part of the requirements could effectively be tested using a vECU. These findings confirmed the potential of SiL simulation environments to not only support, but also enhance, the testing process for vehicle software by providing a cost-effective and flexible complement to traditional HiL test benches. [ABSTRACT FROM AUTHOR]

In order to quantitatively analyze the roughness of the bench floor during open-pit mine blasting, this study proposes a real-time measuring method for the three-dimensional terrain of the bench floor during the excavation process. Real-time monitoring is conducted at the boundary and discrete internal points of the workbench floor during electric shovel operation, utilizing real-time kinematic global navigation satellite system (RTK-GNSS) positioning technology. An improved convex hull algorithm is introduced to automatically extract the optimal boundary of discrete point clouds based on their spatial distribution characteristics. This study establishes a digital elevation model (DEM) using five interpolation algorithms for 3D terrain visualization simulation. Through cross-validation, a comparative analysis of the DEM accuracy, the simulation results of the ordinary kriging interpolation algorithm were found to be optimized. The optimized interpolation algorithm is applied to simulate the 3D terrain in the Dexing open-pit copper mine, and the relevant terrain parameters were calculated. This dataset can serve as a precise foundation for the real-time path planning of elevation blasting design and ground leveling operations. [ABSTRACT FROM AUTHOR]

This paper addresses the design of beam position monitor (BPM) devices suitable for fourth-generation diffraction-limited X-ray storage rings. Detailed investigations of the electromagnetic (EM) phenomena occurring inside the component under various working conditions are carried out by considering different BPM EM models defined by their geometry and materials. Moving from a theoretical characterization of the common round geometry, rhomboidal structures are studied through a careful numerical analysis relying on advanced computer-aided tools. Several critical elements, such as wakefields, pick-up signal extraction, and trapped and propagating modes, are explored from the simulation point of view and from the experimental one, by deploying a manufactured microwave test bench, which is employed to measure the radio frequency behavior of a BPM prototype built at Elettra Sincrotrone Trieste. The aim of the proposed study is to identify a satisfactory tradeoff between achievable performance and practical realizability for BPM devices operating in last-generation light sources. [ABSTRACT FROM AUTHOR]

This paper deals with the reactivation of three test benches of high, medium and low power electric generators for hydraulic energy conversion in the University of Carabobo Hydraulic Laboratory. The method involves three stages: i) Description of three high, medium and low power electric generators for hydraulic energy conversion, ii) Rehabilitation of three high, medium and low power electric generators for hydraulic energy conversion and iii) Evaluation of performance indexes of high, medium and low power electric generators for hydraulic conversion. The results indicate that for the low power electric generator, the position angle of the distributor blades is an experimental factor that has a significant effect on the response variables studied. With respect to the medium and high power electric generators, the most influential factor on operation and power generation is the flow supplied. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) printing is emerging as an innovative technology, which is widely used in cardiovascular disease at bench and bedside. During the last decade, with the development of 3D printing industry, many 3D printed models have been used in clinic, because it can provide the advantage of haptic feedback, direct manipulation, and enhanced doctors' understanding of cardiovascular anatomy and underlying pathologies. In addition to the preparation of 3D printed models, 3D printing technology also shows great application potential in cardiovascular regenerative medicine because it has the advantages of integrating cells, cytokines and materials. Although cardiovascular regenerative medicine application still has a gap between bench and bedside, this gap is gradually narrowing with the development of new materials and new technology of 3D printing recently. In this review, we firstly analyze the characteristics and clinical needs of cardiovascular diseases, and introduce the concept and category of 3D printing technology. Secondly, we summarize the application of 3D printed models, stents, vascular graft, vascular network, and heart organs at bench and bedside. In the end, we discuss the challenges and future perspectives of 3D printing in cardiovascular diseases. [ABSTRACT FROM AUTHOR]

In recent years, polymeric materials have gained prominence as a competitive option for gear manufacturing. Nevertheless, the absence of comprehensive literature addressing the wear due to the coupling of these materials presents a real challenge in response to this innovative trend. Wear of plastic gearwheels represents, in fact, a key issue, traditionally assessed using standard formulations under optimal dry operating conditions. These calculations often rely on coefficients derived from specialized gear tests, but their applicability is constrained to specific polymer–metal combinations. This research was dedicated to the development of a test bench tailored to evaluate the wear of glass fiber-reinforced self-lubricating polymer gearwheels under different operating conditions. This study commenced with a comprehensive exploration of wear phenomena in thermoplastic gearwheels and the inherent challenges associated with utilizing existing standards and the scientific literature for wear analysis. This was followed by a careful evaluation of the operational needs of the test bench, which, starting from a basic solution already implemented, improved its use in various aspects. Finally, this study introduced an optical-based methodology for average linear wear control. This research strived to establish a testing approach that minimizes uncertainties when assessing the wear of thermoplastic gears. [ABSTRACT FROM AUTHOR]

Blasting technology is widely applied in various engineering applications due to its cost-effectiveness and high efficiency, such as in mining, transport infrastructure construction, and building demolition. However, the occurrence of cracking in the rear row has always been a major problem that disrupts mining bench blasting. To address this issue, a three-hole simultaneous blasting technology is proposed in this study. Both numerical simulations and onsite blasting experimental testing were conducted. To aid this endeavor, the three-hole simultaneous blasting and the hole-by-hole blasting methods were adopted to comparatively analyze the severity of the damage caused to the original rock and the effect of rock fragmentation in the rear row. The obtained results highlighted that the outcome of the blast produced by the three-hole simultaneous blasting method is satisfactory, with fewer flying stones and concentrated blasting piles required. Additionally, the original rock in the rear row showed no obvious sign of tensile damage and had uniform fragmentation. It was also found that a block size of less than 60 cm accounts for 100%, while a block size of less than 50 cm accounts for 98.7% of the whole blocks, with no large blocks reported. Moreover, a penetrating horizontal crack occurred in the direction of the connection of the blast hole center when the three-hole simultaneous blasting method was adopted. This resulted in a smooth and flat rear part of the rocks at the interface. Compared to the hole-by-hole blasting method, the three-hole simultaneous blasting method improved the effective stress and displacement at each measurement point. At the measurement point directly at the front of the borehole, the maximum effective stress attained 67.9 GPa, and the maximum displacement reported was 31.9 cm. Overall, it was shown that the three-hole simultaneous blasting technology is applicable in similar applications of mine bench blasting, which is conducive to addressing the rear row original rock strain for onsite bench blasting. [ABSTRACT FROM AUTHOR]

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are currently available for the management of type 2 diabetes mellitus. SGLT2i acts by inhibiting renal SGLT2, thereby increasing glucosuria and lowering serum glucose. Recent trials are emerging supporting a role for SGLT2i irrespective of the diabetic status pointing towards that SGLT2i have other mechanisms of actions beyond blood sugar control. In this review, we will shed light on the role of this group of medications that act as SGLT2i in non-diabetics focusing on pre-clinical and clinical data highlighting the mechanism of renoprotection and effects of SGLT2i in the non-diabetic kidneys. [ABSTRACT FROM AUTHOR]

Volumetric hydraulic drive systems are quite widespread in many industrial sectors. To determine the degree of reliability of hydraulic machines, it is necessary to conduct resource tests. The main requirement for such tests is the compliance of the load level with the operating mode of the hydraulic machine. Analysis of existing methods of creating such a load showed a significant drawback of bench tests—the lack of useful work. Therefore, a number of authors suggest the use of stands with a regenerative drive system. One peculiarity of the work of such stands is the possibility of returning part of the spent energy back to the test system. However, such systems are insufficiently studied and have significant drawbacks. The purpose of this work is to increase the efficiency of the regenerative drive system of the test bench of volumetric hydraulic machines of rotational action by improving the theory and methodology of its calculation and design. This article describes the principle of operation of the circuit of the regenerative drive of the test bench of rotary hydraulic machines. A model of the elastic-dissipative state of the sections of the elements of the hydro-mechanical drive system of the stand is also proposed, which allows for the calculation of the structural and energy parameters of the regenerative hydro-mechanical system. The main structural and functional parameters affecting the operational performance of the system as a whole are also identified. A "test efficiency coefficient" is proposed, which allows for evaluation of the energy efficiency of the test process. [ABSTRACT FROM AUTHOR]

The optimization of the brake systems is crucial for vehicle performance and safety of Formula SAE (FSAE) race cars. This study introduces a specialized brake test bench designed to enhance the understanding and testing of these systems. The bench integrates a rotating mechanical system mounting a brake disc-caliper group, which is driven by an electric motor, a pneumatic brake pedal assembly to simulate real braking conditions, and a comprehensive array of sensors that facilitate the measurement of critical parameters, such as rotation speed, braking torque, oil pressure, and disc temperature. Its structure, sensor integration, and control electronics are fully described, demonstrating the capability to replicate on-track scenarios in a controlled environment. The results underscore the utility of the bench in providing precise and consistent testing conditions essential for analyzing the efficiency, durability, and safety of the braking systems of FSAE race cars. [ABSTRACT FROM AUTHOR]

In recent years, applications exploiting the advantages of tilt-rotors and other vectored thrust propulsion systems have become widespread, particularly in many novel Vertical Takeoff and Landing (VTOL) configurations. These propulsion systems can provide additional control authority, enabling more complex flight modes, but the resulting control systems can be challenging to design due to the mismatch between the vehicle degrees of freedom and physical input variables. These propulsion systems present both advantages and difficulties because they can exert the same overall forces and moments in many different propulsive configurations. This leads to the traditional non-uniqueness problem when using the inverse dynamics control allocation approach, which is the basis of many popular VTOL control algorithms. In this article, a modified Planar VTOL (PVTOL) test bench configuration, which considers an arbitrary number of co-linear tilting rotors, is introduced as a benchmark for the study of the control allocation problem. The resulting propulsion system is then modeled and linearized in a closed and compact form. This allows a simple and systematic derivation of many of the currently used control allocation approaches. According to the proposed PVTOL configuration, a two-rotor test bench is implemented experimentally and a decoupling control allocation strategy based on Singular Value Decomposition (SVD) analysis is developed. The proposed approach is compared with a traditional input mixer algorithm based on physical intuition. The results show that the SVD-based solution achieves better cross-coupling reduction and preserves the main properties of the physically derived approach. Finally, it is shown that the proposed PVTOL configuration is effective for studying the control allocation problem experimentally in a controlled environment and could serve as a benchmark for comparing different approaches. [ABSTRACT FROM AUTHOR]

Airworthiness certification requires proof of structure strength, which is performed generally through a building block approach. To achieve this, representative intermediate-scale experiments generated by test benches are, in general, needed, in addition to material characterization on a coupons scale and structure testing on a large scale. The VERTEX test bench can generate the combined loading of tension/compression-shear-pressure on structural elements and was modelled with Finite Elements to perform virtual testing, representative of its intermediate-scale specificity. The numerous bolted joints of the bench were modelled and their behavior was identified in previous tests, so the model could quantitatively estimate the transfer function of the bench, which is the relationship between the displacements imposed by the jacks and the resulting loads on a given sample. The VERTEX model was identified to represent load shapes and amplitudes based on a training set and was later confronted by a validation set of tests of tension and shear. A model with ideal boundary conditions was also developed for a comparison, but it failed to predict some load shape specificities and did not give any indication of the loading amplitude. Application cases of the developed model are shown to assess a range of virtual testing possibilities. [ABSTRACT FROM AUTHOR]

This study aimed to explore the differences in attack-defense performance between the top and bottom teams for starting and bench players during the Tokyo Olympics men's basketball competition, to determine the relationship between the attack-defense performance of starting and bench players and the final competition rankings, as well as with each performance indicator. The rank-sum ratio (RSR) comprehensive evaluation was employed to describe the attack-defense performance of starting and bench players. Additionally, an independent sample t-test, Spearman Rho Correlation, and Pearson Correlation were conducted to test the differences and relationships between the various variables at a 0.05 level of significance, respectively. The results indicated that the top four teams showed significant differences in the attack-defense performance of their starting players compared to the bottom four teams (p = 0.021), mainly in terms of 3-point shooting percentage (p = 0.042) and free throw shooting percentage (p = 0.044). Besides that, the attack-defense ranks of both starting players (p = 0.004, r = 0.757) and bench players (p = 0.020, r = 0.658) had a significant correlation with the final rankings. Points per game, 2-point field goal percentage, and assists had a statistically significant (p<0.01) and strong positive correlation (0.70

A study on the possibility of integrating a micro-turbogenerator system into a multi-rotor UAV platform was performed along with a performance evaluation of the result. This paper presents the design and development of a micro-turbogenerator system constructed from commercially available components and the associated test bench that was needed to validate the system. The goal of the micro-turbogenerator system was to replace the electrical power source (the batteries) of an experimental UAV. Substituting the electrical power source with a hybrid propulsion system has the potential to enhance the UAV's endurance and functionality, rendering it more versatile and efficient. The hybrid propulsion system involves the use of a commercially available micro-gas turbine that propels an electric generator, supplying the required electrical power for the UAV's electric propulsion system. Integrating this micro-turbogenerator system ensures a substantial increase in UAV endurance. The test bench was used to assess the performance of the micro-turbogenerator system and formulate a control law necessary for maintaining a balance between the power generated by the system and the power consumed by the UAV. The developed test bench yielded crucial data, including electric power, generated voltage, generator speed, and power consumption (simulating the UAV in this case). During the testing campaign, the variation in the main physical quantities involved in the command and control of the hybrid propulsion system was registered and analyzed. A total power of 700 W was obtained during the tests, which is the maximum that can be registered for maintaining a power of 25 V. [ABSTRACT FROM AUTHOR]

The regeneration of highly dynamic driving maneuvers on vehicle test benches is challenging due to several influences, such as power losses, vibrations in the overall system that involves the vehicle with the test bench, uncertainties in the model parameterization, and time delays from both the test bench and the measurement systems. In order to improve the dynamic response of the vehicle test bench and to overcome system disturbances, we employed different types of control algorithms for a mechanical multi-mass model. First, those controllers are extensively investigated in the frequency domain to analyze their stability and evaluate the noise rejection quality. Then, the expectations from the frequency analysis are confirmed in a time-domain simulation. Furthermore, sensitivity analysis tests were conducted to evaluate each controller's robustness against the modeling parameters' uncertainty. The linear quadratic controller with integral action demonstrated the best compromise between performance and robustness. [ABSTRACT FROM AUTHOR]

Since electric power steering has replaced hydraulic power steering in passenger cars, steering feedback has become a challenging task in steering system development. Test benches represent a valid approach for improving steering feedback since they allow investigations without the real vehicle. To improve the applicability of feedback evaluations on a steering test bench, this paper aims to identify improvements in the current evaluation technique to obtain objective parameters that correlate with a subjective evaluation of safety-relevant steering feedback. Therefore, a previously reported approach of a chirp rack force excitation, using the magnitude of the transfer function from the rack force to steering wheel torque to describe steering feedback, is compared to a similar identification approach in which a pseudo-random-binary-sequence signal is utilized. To reflect realistic applications, driving maneuvers are transferred to the test bench to identify relevant objective data. For a valid representation of the steering wheel operation, a human grip model is implemented and compared to a fixed steering wheel angle control. It is shown that the random signal represents a valid and, on average, improved approach to objectively evaluating the steering feedback. Furthermore, a recommendation can be made to include the human grip model in the feedback evaluation tests, as the identified correlation results are improved by its inclusion. The identified parameters and methods represent an improvement for future steering feedback development. [ABSTRACT FROM AUTHOR]