Stabilization System Research Articles

A Lego-Like Reconfigurable Microfluidic Stabilizer System with Tunable Fluidic RC Constants and Stabilization Ratios.

In microfluidic systems, it is important to maintain flow stability to execute various functions, such as chemical reactions, cell transportation, and liquid injection. However, traditional flow sources, often bulky and prone to unpredictable fluctuations, limit the portability and broader application of these systems. Existing fluidic stabilizers, typically designed for specific flow sources, lack reconfigurability and adaptability in terms of the stabilization ratios. To address these limitations, a modular and standardized stabilizer system with tunable stabilization ratios is required. In this work, we present a Lego-like modular microfluidic stabilizer system, which is fabricated using 3D printing and offers multi-level stabilization combinations and customizable stabilization ratios through the control of fluidic RC constants, making it adaptable to various microfluidic systems. A simplified three-element circuit model is used to characterize the system by straightforwardly extracting the RC constant without intricate calculations of the fluidic resistance and capacitance. By utilizing a simplified three-element model, the stabilizer yields two well-fitted operational curves, demonstrating an R-square of 0.95, and provides an optimal stabilization ratio below 1%. To evaluate the system's effectiveness, unstable input flow at different working frequencies is stabilized, and droplet generation experiments are conducted and discussed. The results show that the microfluidic stabilizer system significantly reduces flow fluctuations and enhances droplet uniformity. This system provides a new avenue for microfluidic stabilization with a tunable stabilization ratio, and its plug-and-play design can be effectively applied across diverse applications to finely tune fluid flow behaviors in microfluidic devices.

Implications of vertical stability control on the SPARC tokamak

To achieve its performance goals, SPARC plans to operate in equilibrium configurations with a strong elongation of κareal∼1.75 , which in turn will destabilize the n = 0 vertical instability. However, SPARC also features a relatively thick conducting wall that is designed to withstand disruption forces, leading to lower vertical instability growth rates than usually encountered. In this work, we use the TokSyS framework to survey families of accessible shapes near the SPARC baseline configuration, finding maximum growth rates in the range of γ≲100 s−1. The addition of steel vertical stability plates has only a modest ( ∼25% ) effect on reducing the vertical growth rate and almost no effect on the plasma controllability when the full vertical stability system is taken into account, providing flexibility in the plate conductivity in the SPARC design. Analysis of the maximum controllable displacement on SPARC is used to inform the power supply voltage and current limit requirements needed to control an initial vertical displacement of 5% of the minor radius. From the expected spectra of plasma disturbances and diagnostic noise, requirements for filter latency and vertical stability coil heating tolerances are also obtained. Small modifications to the outboard limiter location are suggested to allow for an unmitigated vertical disturbance as large as 5% of the minor radius without allowing the plasma to become limited. Further, investigations with the 3D COMSOL code reveal that strategic inclusion of insulating structures within the VSC supports are needed to maintain sufficient magnetic response. The workflows presented here help to establish a model for the integrated predictive design for future devices by coupling engineering decisions with physics needs.

Designing Pickering Emulsions Stabilized by Modified Cassava Starch Nanoparticles: Effect of Curcumin Encapsulation

Curcumin is a hydrophobic bioactive compound, and its incorporation into lipid-based carriers can enhance its bioaccessibility and maintain its stability over time. Pickering emulsions are long-term stability systems, effective for encapsulation, protection, and delivery of bioactive compounds. This study aimed to produce Pickering oil-in-water (O/W) emulsions stabilized by cassava starch nanoparticles (native or modified by heat–moisture treatment (HMT)) with high kinetic stability to encapsulate curcumin. The effect of curcumin incorporation on emulsion features was also assessed, as well as curcumin stability over time. Native starch nanoparticles (NSNPs) were not effective stabilizers in the concentration range of 0.8 to 4 wt%. Otherwise, modified starch nanoparticles (HSNPs) at 4 wt% produced a long-term stability Pickering emulsion, which was used to encapsulate curcumin (0.07 wt%). Confocal laser scanning microscopy (CLSM) showed that HSNPs were located at the droplet’s interface. The interfacial tension for HSNPs exhibited initial values from 40 to 33 mN/m, quickly reaching equilibrium. These findings suggest that HSNPs exhibit low surface activity and the stabilization mechanism of emulsion is based on steric hindrance. The stabilization by steric hindrance is supported by the low zeta potential value (−5.39 mV). Stable emulsions showed shear thinning behavior, and the power-law model demonstrated excellent fit to experimental data (R2 ≥ 0.998). The addition of curcumin reduced the interfacial tension, droplet size, apparent viscosity, and consistency index, indicating that this bioactive compound can also act at the interface. After 60 days, curcumin degradation was fully avoided. Our findings indicated that HSNP-stabilized Pickering emulsions can protect encapsulated curcumin from degradation.

Simplified 1.5 μm Distributed Feedback Semiconductor Laser (DFB-LD) Frequency Stabilization System Based on Gas Absorption Chamber

The classical 1.5 μm band frequency-stabilized laser using acetylene gas saturated absorption can achieve high frequency stability and reproducibility, but its system design is complex and bulky. For some practical applications, a simple, compact system containing anti-interference abilities is preferred. In this study, a low-cost and simple-structured 1.5 μm frequency-stabilized laser is constructed using digital control methods, wavelength modulation technology, and acetylene gas absorption. The fiber input and output optical devices of the system significantly simplify the optical path and reduce the volume of the system. The error signal is obtained by the first-order differential method, and a combination of the high-speed comparator circuit and the microcontroller unit (MCU) is used to detect the error signal. Through the feedback control method of coarse temperature adjustment and fine current adjustment, the second-level frequency stability of the laser is stabilized within 100 kHz, that is, the frequency stability reaches 10​−10. The designed system achieved continuous and stable operation for more than 6 h, and the long-term frequency stability reached 10​−9.

Bi-planar magnetic stabilisation coils for an inertial sensor based on atom interferometry

Inertial sensors that measure the acceleration of ultracold atoms promise unrivalled accuracy compared to classical equivalents. However, atomic systems are sensitive to various perturbations, including magnetic fields, which can introduce measurement inaccuracies. To address this challenge, we have designed, manufactured, and validated a magnetic field stabilisation system for a quantum sensor based on atom interferometry. We solve for the magnetic field generated by surface currents in-between a pair of bi-rectangular coils and approximate the surface current using discrete wires. The wires are wound by-hand onto machined panels which are retrofitted onto the existing mounting structure of the sensor without interfering with any experimental components. Along the central 60mm of the y-axis, which aligns with the trajectory of the atoms during interferometry, the coils are measured to generate an independent uniform axial magnetic field with a strength of Bz=22.81±0.01μT/A [mean±2σstd. error] and an independent linear axial field gradient of strength dBz/dy=10.6±0.1μT/Am. The uniform Bz field is measured to deviate by a maximum value of 1.3% in the same region, which is a factor of three times more uniform than the previously-used on-sensor rectangular Bz compensation set.

Synthesis of Robust System for Spatial Stabilization of Ground Vehicle Equipment

Synthesis of Robust System for Spatial Stabilization of Ground Vehicle Equipment

СПОСОБИ МЕХАНІЧНОЇ СТАБІЛІЗАЦІЇ ЧАСТОТИ ОБЕРТАННЯ ЕЛЕКТРИЧНОГО ГЕНЕРАТОРА СИЛОВОЇ УСТАНОВКИ

When studying the electrical on-board system of the vehicle as a whole, it is necessary to consider the dynamic characteristics of all its components. One of the links of the system is considered - a mechanical variator for stabilizing the frequency of rotation of the generator rotor. When the generator is driven by an aircraft engine, there are factors that prevent its stable operation. The rotation frequency of the drive motor is constantly changing, so there is a problem related to the creation of a high-quality system of mechanical stabilization of the rotation frequency. Possible methods of stabilizing the frequency of rotation of the electric generator rotor by using stepless variators are considered. When analyzing the possible types of stepless variable speed variators, mechanical variators were chosen, which have a number of advantages over other types, such as their compactness, low cost, high efficiency, etc. In particular, it is proposed to use differential gear mechanisms of various schemes as stabilizers: a differential variator made using schemes IA and AI, as well as a differential mechanism AI with a free carrier. As devices that provide self-regulation of the output rotation frequency, it is proposed to use speed regulators, the principle of operation of which is based on the use of centrifugal force, which changes when the rotation frequency changes at the input to the variator. A concrete example for a differential mechanism (AI) shows how to perform kinematic and force calculations to ensure constancy of the output speed when the input speed changes within ± 6%.

Selective and Sensitive Detection of Fe3+ Ions Using a Red-Emissive Fluorescent Probe Based on Triphenylamine and Perylene-Linked Conjugated Microporous Polymer.

The Expansion of modern industry underscores the urgent need to address heavy metal pollution, which is a threat to human-health and environment. Efforts are underwent to develop precise technologies for detecting heavy metal ions (M+-ion). One promising approach involves the use of Conjugated Microporous Polymers (CMPs) modified with Triphenylamine (TPA) anderylene (Peryl), known as TPA-Peryl-CMP, which emits strong refluorescence. Various analytical techniques, such as Brunauer-Emmett-Teller analysis, Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and thermogravimetric analysis (TGA), are utilized to characterize the synthesized TPA-Peryl-CMP and understand its functional properties. In addition to its remarkable fluorescence behavior, TPA-Peryl-CMP shows promise as a sensor for Fe3+ ions using a turn-off strategy. Due to its exceptional stability and robust π-electron system, this platform demonstrates remarkable sensitivity and selectivity, significantly improving detection capabilities for specific analytes. Detailed procedures related to the mechanism for detecting Fe3+ ions are outlined for sensing Fe3+ ions, revealing a notably strong linear correlation within the concentration range of 0-3µM, with a correlation coefficient of 0.9936 and the Limit of detection (LOD) 20nM. It is anticipated that development of such a kind of TPA-Peryl-CMP will observe broader applications in detecting various analytes related to environmental and biological systems.

Distributed optimization for interconnected nonlinear multi-agent systems via output feedback

In this paper, the distributed optimization for a class of interconnected nonlinear multi-agent systems is considered via output feedback control. The problem is challenging because only the system’s output is available. The system’s states and optimal values are estimated by two reduced-order filters and an optimal observer, respectively. Then the final optimal algorithm is designed based on a back-stepping method. The convergence analysis is built by using Lyapunov stability and perturbation system theory. Some examples are presented to illustrate the effectiveness of the designed optimal algorithm.

Numerical and Experimental Analysis of Lifting Forces of Fin Stabilizers with Fin–Hull Interaction

A fin stabilizer is one of the most effective and frequently used anti-roll devices for maintaining a ship’s operational safety and passengers’ comfort. However, the discrepancy between theoretical hydrofoil-based predictions and the actual dynamic lift force of fin stabilizers due to fin–hull interactions requires more research attention. This study investigates the effect of fin stabilizers on mitigating roll motion through the performance of extensive computational fluid dynamic (CFD) simulations over a range of fin angles and ship speeds. Model tests were carried out to validate the drag and motion results obtained from numerical analyses. The results show that fin stabilizers significantly reduce the roll motion, with the lift coefficient values influenced by the Reynolds number, leading to differences between the theoretical and Reynolds-averaged Navier–Stokes (RANS) calculations. At a high Froude number (Fr), the actual fin lift is about half of the theoretical value. These findings highlight the requirement of selecting an adequate fin area at the predominant ship speeds and ensuring an effective anti-roll effect with fin–hull interaction. This study provides a significant reference for ship design, as well as stabilization system control and optimization.

Моделювання системи стабілізації обладнання мобільного робота в умовах руху по місцевості з нахилом та нерівностями

The article is devoted to the development of a system of stabilization and guidance of equipment, which is installed on land-based small-scale mobile robots of the wheel type. During the operation of such objects, problems arise due to modes of movement, over-coming obstacles, movement on terrain with different types and profiles of the terrain. During such a movement, there are disturbances in the place of installation of the equip-ment, which leads to its deviation from the horizon plane. A stabilization system is used to ensure accuracy requirements in a wide range of movement speeds and operating condi-tions of mobile robots. In the article, the simulation of the stabilization system under the action of external disturbances caused by the influence of the movement of the mobile robot through terrain with a complex profile in combination with the inclination of the different steepness of the movement surface was carried out. A stabilization system simulation scheme with a basic structure and with an additionally introduced proportional-integrating controller was developed, realizations of various types of disturbances were generated by a combination of different inclination angles and different road profile classes. As a result of the simula-tion, the time realizations of the system’s response to the generated disturbances, which are the dependences of the stabilization error, were obtained, the root mean square devia-tions and the maximum value of the angle of deviation of the place of installation of the equipment from the horizon plane were determined. The results of the study showed that the system with an additionally introduced pro-portional-integrating regulator provides acceptable stabilization error values under the con-ditions of action of all considered types of disturbances. The obtained results will be used for the development of an adaptive digital system of stabilization of equipment installed on small-sized mobile robots of the wheel type.

Increasing Motivation of Iranian Students to Continue Education in Germany. Challenges and Opportunities in Academia

The emigration of educated individuals from Iran has become a prominent and multifaceted issue in recent years, eliciting diverse perspectives. Statistical analysis reveals a substantial surge in the number of Iranian students electing Germany as their preferred destination for higher education. Notably, the count of Iranian students studying in Germany has witnessed a more than threefold increase, soaring from 4,182 students in 2008 to 13,279 in 2023. Moreover, the student population has nearly tripled from 4,182 in 2008 to 11,573 in 2021, signifying a 45% surge compared to the preceding year. This prompts an inquiry into the factors underpinning Iranian students' preference for Germany. To delve into this phenomenon, a survey was conducted among Iranians residing in Germany. The survey outcomes reveal that the deteriorating living conditions in Iran, coupled with Germany's political stability and robust social welfare system, have played pivotal roles in motivating students and university graduates to pursue education abroad. Educational advancement emerges as a secondary consideration in their decision-making process.

A Comparative Study to Analyze the Effect of Lumbar Stabilization and Conventional Back Extension Exercises on Mechanical Pain in Patients with Chronic Low Back Pain in Greater Noida

Lumbar discomfort is a major problem due to its harmful effects on health and high frequency in the general population. Depending on where and how long the pain lasts, there are three general categorizations for Lumbar discomfort: acute less than 6 weeks, sub-acute 6 to 12 weeks, and chronic more than 12 weeks. Several theories concerning the cause of nonspecific LBP feature poor posture, low body mass, hamstring flexibility, psychological discomfort, diminished trunk extensor endurance, and faulty muscular control of trunk. Pain in the lower back is a challenging illness which can result from injuries pertaining to the muscles and ligaments providing support vertebral column or from overuse or strain. One common treatment method for Lumbar discomfort is exercise therapy. This includes diverse forms of therapies including muscular strengthening, several forms of flexibility and stretching, and cardiovascular exercise for overall physical fitness. Normally, the stabilization system's job is to give the spine enough stability to meet the demands of changing circumstances immediately due to the posture changes with static and dynamic loads. As Per traditional understanding, spinal stabilization primarily relies on spinal biomechanics, the intervertebral disc, spinal ligaments, and osseous components. The stabilization and mobility of the lumbar spine can be facilitated by any muscle that exits the lumbar region. However, according to certain research, the lumbar multifidus and transverses abdominis muscles are very crucial for the stability of the lumbar segment. There is preliminary data indicating that those with long-term Lumbar discomfort do not properly recruit their core muscles and display core weakness13. Standard Exercise for back extension and exercises for lumbar stability both are used to treat low back discomfort. Thus, an effort is undertaken to compare and investigate the benefits of traditional back extension exercises and lumbar stabilization activities in patients with chronic Lumbar discomfort.

Data‐driven adaptive control design for active stabilization of stratospheric airship imaging platform: A characteristic model approach

AbstractIn response to the problem of disturbance in the imaging equipment of stratospheric airships, this study designs a vibration isolation and stability system for carrying imaging equipment. The system mainly consists of microprocessor, gimbal, voice coil motor(VCM) and rubber ring. By using adaptive control law based on characteristic model to control the double closed control loop of the motor composed of position loop and speed loop, the camera deflection caused by disturbance is effectively eliminated. Furthermore, in vertical vibration suppression, the adaptive control law based on the characteristic model is also applied to the double closed control loop of the voice coil motor, which removes most of the vertical vibration and realizes active vibration isolation. The passive isolation of the system is completed by rubber rings. The experimental results show that the vibration isolation and stabilization system have good performance in complex disturbance environments, effectively stabilizing the imaging equipment.

A Review Study on Belt Wall in Non-Regular Buildings in Various India Earthquake Zones

To reinforce a building's central walls and external columns and boost its stability against overturning, outriggers are robust horizontal frameworks like beams and frames. While cantilevers have been an attribute of buildings for more than fifty years, their performance has been enhanced by innovative design concepts. The structural system known as the foundation system is made up of horizontal cantilever portions that are fastened to the structure's external columns and interior core. The system's lateral stiffness and central moment arm are both enhanced by this link. By joining the core and the building supports, the stabilizer lowers the back moments inside the core and transfers moments from the core to the exterior supports. Steel, concrete, and composite materials are just a few of the elements that can be used to make stabilization systems. Usually the core is positioned on one side of the building and the stabilizers expand on the opposite side, or the stabilizers expand on one side of the central core. To stop lateral movement, the perimeter of the building is attached together and expanded by column-connecting walls. Wall-mounted stabilizers are more efficient than wall-free ones. The center wall cannot freely rotate on the external columns due to the stabilizing arm. The location of outriggers and tie rods, the quantity of outriggers, the form of the structure, the type of core (steel or concrete), and the height from floor to ceiling are just a few of the elements that might impact how well outriggers and straps function in the structure. Several studies were selected for this review study with the purpose of analyzing the impact of belt walls on irregular structures. Obtain a thorough analysis of the types of irregular buildings and how earthquakes affect these constructions. Earthquake zones are used in India to categorize the degree of seismic loading. Keywords: Belt Wall, earthquake zone, Irregularities of Building, Storey displacement, bending moment etc.

Trends in corruption and shadow economy in European countries

Corruption and the shadow economy are among the most pressing issues facing European countries. These phenomena significantly impact the socio-economic development, political stability, and legal systems of states. The purpose of the paper is to analyze the trends of corruption and the shadow economy in 34 European countries over the period from 2010 to 2022. The research employed tools such as grouping, comparison and generalization methods, time series analysis, and descriptive statistics calculations. Calculations were based on World Bank data using StataSE 18 software. Analyzing the standard deviation, minimum, and maximum values of corruption and shadow economy indicators identifies the most variable indicators: the indicator of primary government expenditures as initially approved budgets and the corruption perception index. It was found that despite the implementation of numerous anti-corruption reforms and regulatory measures, countries such as Albania, Moldova, Ukraine, and Bulgaria continue to face high levels of corruption, as evidenced by their low corruption perception index levels. The main reasons for this included weak enforcement mechanisms, gaps in accountability, and low levels of transparency in public administration. The least corrupt European countries were Denmark, Norway, Finland, Switzerland, and Sweden. This research observed high levels of the shadow economy in Ukraine, Cyprus, and Moldova, while Denmark, Norway, and Sweden demonstrated the lowest levels. The results of the study can be used to develop organisational and economic measures to combat corruption and the shadow economy by public authorities, business entities and other economic agents, which is important for the economic growth of European countries.

Diet enrichment with omega-3 fatty acids: effect on productive performance, egg quality traits, yolk fatty acid profiles, oxidative stability, blood biochemistry and immune system

ABSTRACT The objective of this study was to examine the effects of enriching the diet with Omega-3 fatty acids on the productive performance, yolk fatty acid profiles, oxidative stability, blood biochemistry, and immune system of laying hens. Enriching the diet with Omega-3 improved egg production and FCR (P < 0.05). Docosahexaenoic acid (DHA) and total omega-3 fatty acids in the yolk increased linearly with Salomega level (P < 0.05). Serum cholesterol and triglyceride decreased, but HDL content increased parallel to the Salomega level in the diet (P < 0.05). The MDA level in the yolk of bird eggs of the 3 or 4% Salomega treatment was higher than the MDA level of the control group (P < 0.05). In conclusion, the enrichment of laying hens’ diet with 3 and 4% salomega can enhance egg production, elevate the levels of Omega-3 fatty acids, and decrease the oxidative stability of yolk lipids.

Advances in Exosome-Based Therapies for the Repair of Peripheral Nerve Injuries.

Peripheral nerve injuries (PNIs) are the term used to describe injuries that occur to the nerve fibers of the peripheral nervous system (PNS). Such injuries may be caused by trauma, infection, or aberrant immunological response. Although the peripheral nervous system has a limited capacity for self-repair, in cases of severe damage, this process is either interrupted entirely or is only partially completed. The evaluation of variables that promote the repair of peripheral nerves has consistently been a focal point. Exosomes are a subtype of extracellular vesicles that originate from cellular sources and possess abundant proteins, lipids, and nucleic acids, play a critical role in facilitating intercellular communication. Due to their modifiable composition, they possess exceptional capabilities as carriers for therapeutic compounds, including but not limited to mRNAs or microRNAs. Exosome-based therapies have gained significant attention in the treatment of several nervous system diseases due to their advantageous properties, such as low toxicity, high stability, and limited immune system activation. The objective of this review article is to provide an overview of exosome-based treatments that have been developed in recent years for a range of PNIs, including nerve trauma, diabetic neuropathy, amyotrophic lateral sclerosis (ALS), glaucoma, and Guillain-Barre syndrome (GBS). It was concluded that exosomes could provide favorable results in the improvement of peripheral PNIs by facilitating the transfer of regenerative factors. The development of bioengineered exosome therapy for PNIs should be given more attention to enhance the efficacy of exosome treatment for PNIs.

Financial Stability and Innovation: Interconnection and Development Prospects

The development of the modern sphere of technologies ensures active implementation of various types of innovations in the activities of modern companies. If innovations are rationally planned, they can have a positive impact on the financial stability of business and the economy as a whole. At the same time, Ukrainian innovation activity has a huge unrealised potential, which can be realised under more favourable external conditions and high-quality planning of the specifics of innovation implementation. The purpose of the study is to summarise approaches to determining the relationship between innovation and financial stability of modern business. In order to achieve this goal, it is necessary to solve a number of urgent tasks, in particular: to determine the scale of innovation activity of modern business in the world and in Ukraine; to outline the key tasks that can be solved by innovative tools if they are implemented in business activities; to specify the directions of ensuring financial stability through the introduction of innovations. The research was based on an in-depth review of more than 50 scientific sources, including articles indexed in leading scientometric databases. The study found that the global innovation market is at the stage of active development, while Ukrainian enterprises are not currently realising their full innovation potential due to unfavourable environmental conditions. The study also identifies the tasks that can be solved by innovative tools, provided they are implemented in business activities. It is determined that the application of digital marketing tools and the use of social networks to promote products allow expanding the audience, which can have a positive impact on the development of the financial stability system. Working with data, planning, and processing data using the latest technologies can also have a positive impact on financial stability. A separate link is the optimisation of business processes (financial, production, procurement, etc.) using the latest information management tools (artificial intelligence, big data, cloud technologies), which can improve the information component of financial stability.

Investigating the impact of unstable network connections on the cluster running a consensus algorithm

This study explores the effects of unstable network connections on the operational efficiency of a computing cluster executing a consensus algorithm. Consensus algorithms are critical for maintaining the integrity and consistency of distributed systems, particularly in blockchain technologies and distributed databases. However, the reliability of these systems is often challenged by network instability, which can lead to delays, decreased throughput, and, in severe cases, loss of consensus. Research employs simulation experiments to quantify the impact of network disruptions such as latency variability on cluster running consensus algorithm. By systematically varying network conditions and observing the resultant effects on a cluster running a representative consensus algorithm, we identify critical thresholds of instability that significantly impair system performance. The findings contribute to a deeper understanding of the dynamics between network stability and distributed system, offering valuable insights for developers and engineers tasked with designing and maintaining robust distributed systems in the face of network unreliability.