bluuebunny/crossref_metadata_2025_split huggingface dataset:
External field and critical exponents in controlling dynamics on complex networks
Authors: Sanhedrai Hillel , Havlin Shlomo 
Published: January 2023

Abstract
Dynamical processes on complex networks, ranging from biological, technological and social systems, show phase transitions (PTs) between distinct global states of the system. Often, such transitions rely upon the interplay between the structure and dynamics that takes place on it, such that weak connectivity, either sparse network or frail interactions, might lead to global activity collapse, while strong connectivity leads to high activity. Here, we show that controlling dynamics of a fraction of the nodes in such systems acts as an external field in a continuous PT. As such, it defines corresponding critical exponents, both at equilibrium and of the transient time. We find the critical exponents for a general class of dynamics using the leading orders of the dynamic functions. By applying this framework to three examples, we reveal distinct universality classes.
Escape from the potential well: accelerating by shaping and noise tuning
Authors: Dybiec Bartłomiej , Zawiślak Mikołaj 
Published: January 2023

Abstract
Noise driven escape from the potential well is the basic component of various noise induced effects. The efficiency of the escape process or time scales matching is responsible for occurrence of the stochastic resonance and (stochastic) resonant activation. Here, we are extending the discussion on how the structure of the potential can be used to optimize the mean first passage time. It is demonstrated that corrugation of the potential can be beneficial under action of the weak Gaussian white noise. Furthermore, we show that the noise tuning can be more effective than shaping the potential. Therefore, action of the tuned additive α-stable noise can accelerate the escape kinetics more than corrugation of the potential. Finally, we demonstrate that mean first passage time from a potential well can be a non-monotonous function of the stability index α.
Quantum teleportation in a two-superconducting qubit system under dephasing noisy channel: role of Josephson and mutual coupling energies
Authors: Zidan Nour , ur Rahman Atta , Haddadi Saeed 
Published: January 2023

Abstract
We investigate the average fidelity of teleportation for a system of two superconducting qubits under a dephasing noisy channel. Using the classical fidelity threshold concept, we disclose the effectiveness of the current channel to remain either in the classical or in the quantum domain. Various parameters of the assumed scheme help us to achieve high average fidelity of teleportation in the current configuration.
Magnetic temporal interference for noninvasive and focal brain stimulation
Authors: Khalifa Adam , Abrishami Seyed Mahdi , Zaeimbashi Mohsen , Tang Alexander D , Coughlin Brian , Rodger Jennifer , Sun Nian X , Cash Sydney S 
Published: January 2023

Abstract

Objective. Noninvasive focal stimulation of deep brain regions has been a major goal for neuroscience and neuromodulation in the past three decades. Transcranial magnetic stimulation (TMS), for instance, cannot target deep regions in the brain without activating the overlying tissues and has poor spatial resolution. In this manuscript, we propose a new concept that relies on the temporal interference (TI) of two high-frequency magnetic fields generated by two electromagnetic solenoids. Approach. To illustrate the concept, custom solenoids were fabricated and optimized to generate temporal interfering electric fields for rodent brain stimulation. C-Fos expression was used to track neuronal activation. Main result. C-Fos expression was not present in regions impacted by only one high-frequency magnetic field indicating ineffective recruitment of neural activity in non-target regions. In contrast, regions impacted by two fields that interfere to create a low-frequency envelope display a strong increase in c-Fos expression. Significance. Therefore, this magnetic temporal interference solenoid-based system provides a framework to perform further stimulation studies that would investigate the advantages it could bring over conventional TMS systems.
Instabilities and turbulence in stellarators from the perspective of global codes
Authors: Sánchez E. , Bañón Navarro A. , Wilms F. , Borchardt M. , Kleiber R. , Jenko F. 
Published: January 2023

Abstract
In this work, a comparison of the global gyrokinetic codes EUTERPE and GENE-3D in stellarator configurations of the Large Helical Device (LHD) and the Wendelstein 7-X (W7-X) is carried out. In linear simulations with adiabatic electrons, excellent agreement is found in the mode numbers, growth rate, frequency, mode structure, and spatial localization of the most unstable mode in LHD. In W7-X, the dependence of the growth rate and frequency with the mode number is well reproduced by both codes. The codes are also compared in linear simulations with kinetic ions and electrons in W7-X using model profiles, and reasonable agreement is found in the wavenumber of the most unstable modes. A stabilization of small-scale modes in kinetic-electron simulations with respect to the adiabatic-electron case is consistently found in both codes. Nonlinear simulations using adiabatic electrons and model profiles are also studied and the heat fluxes are compared. Very good agreement is found in the turbulent ion heat fluxes in both LHD and W7-X. Two problems that cannot be properly accounted for in local flux tube codes are studied: the localization of instabilities and turbulence over the flux surface and the influence of a background long-wavelength electric field. Good agreement between codes is found with respect to the spatial localization of instabilities and turbulence over the flux surface. The localization of saturated turbulence is found in both codes to be much smaller than that of the linear instabilities and smaller than previously reported in full-surface radially-local simulations. The influence of the electric field on the localization is also found to be smaller in the developed turbulent sate that in the linear phase, and smaller than in previous works. A stabilizing effect of a constant electric field on the linearly unstable modes is found in both codes. A moderate reduction of turbulent transport by the radial electric field, with small dependence with the sign of the electric field, is also found.
Radiant capillary heat exchangers – power calculation for optimal heating and cooling
Authors: Gendelis Staņislavs , Teličko Jevgēnijs , Jakovičs Andris , Bukans Indulis 
Published: January 2023

Abstract
The issue of switching to renewable energy sources becomes very actual and it is important not only to change the energy source, but also the reduce the final energy needs by improving the energy efficiency of buildings and usage of efficient heating systems. Heat pumps as the most popular renewable energy source are widely used, but their energy efficiency is depending on temperature of the supplied energy carrier. The most efficient are radiant capillary heat exchangers with a large surface area and a low temperature, which typically does not exceed 30°C. Another advantage of radiant capillary heat exchangers is the possibility to operate them in both - heating and cooling modes. Unlike the underfloor heating solution, where the role of thermal convection is very important, the built-in radiant capillary heat exchanger systems provide the energy mainly due to thermal radiation. This study explores two modelling approaches for determination of required power and corresponding area of radiant capillary heat exchangers to be installed in a room to provide heating and cooling: simplified approach, which allows to create the heat balance with a minimum amount of input data and a precise standard-based approach. Calculations were made for three different rooms with variable glazing area and spatial orientation using both approaches. Analysis of the calculation results shows the limits of the simplified method, which overestimates heating need and underestimates cooling need, and the main reason for such differences is simplification of room orientation and subsequent solar heat gains. As the calculated cooling power is less than heating power, therefore the heating estimation is sufficient to estimate the amount of radiant capillary heat exchangers in small/medium rooms for providing both heating and cooling in the climatic conditions of Riga. The use of complex, comprehensive modelling approaches is necessary for rooms with large glazed areas, where the simplified method gives incorrect estimations.
Method and apparatus for dynamic testing of structural joints
Authors: Mironovs Viktors , Zemcenkovs Vjaceslavs , Serdjuks Dmitrijs , Lapkovskis Vjaceslavs , Tatarinovs Aleksejs , Kurtenoks Viktors 
Published: January 2023

Abstract
The dynamic testing technique is used during the design phase of structures and series production. This test evaluates the structural capacity, especially of the assemblies, to withstand different forces and rates of impact encountered under realistic operational conditions. This study proposes a magnetic pulse exciter for high-speed impact loading in dynamic tests because of its capability to provide single and repeatable pulse loading over a wide range of force up to 20 kN and pulse durations from 10 up to 1000 ms. The method transforms accumulated electrical energy in a capacitor bank into mechanical energy. For experimental investigations, flat and cylindrical coil devices were used for a capacitor-type pulse current generator. The proposed method has been experimentally validated on timber beams in a specified volume of force loading. The technique demonstrated a potential for controlling force and energy parameters. The effects of operating voltage on coil and ‘metal plate - coil’ distance on the amplitude of dynamic loading have been investigated. Aluminium and steel plates fastened to the object at the point of impact were used to improve excitation efficiency. The developed technique can be used in experimental studies on model joints and real objects.
Compressive and flexural behavior of glass fiber-reinforced concrete
Authors: Annamaneni K K , Pedarla K 
Published: January 2023

Abstract
Utilizing fibre-reinforced concrete is still a difficulty for present engineers. Generally, it is acknowledged that the mechanical, cracking and fracture qualities of fibre-reinforced concrete are much better than those of conventional concrete. The addition of fibres to the concrete matrix mitigates its fragility. Typically, short fibres are utilised in concrete to prevent cracks caused by drying and autogenous shrinkage. Currently, there is a substantial increase in the use of short alkali-resistant glass fibres. This experiment was conducted to examine the influence of glass fibre reinforcement on the compressive and flexural behaviour of concrete. This research investigates the characteristics of glass fibres reinforced concrete (GFRC) after 7 and 28 days of curing, such that GFRC may be employed in construction. Concrete containing short alkali-resistant glass fibres of 36 mm in length and 1% volume fraction (VF) was developed for this purpose. The testing findings revealed that the average compressive strength of GFRC after 28 days of curing was 72.06 MPa. The flexural properties of GFRC are determined, and the 7-day and 28-day average bending strengths of GFRC concrete samples are 6.46 MPa and 7.94 MPa, respectively, indicating that GFRC responds well under loading conditions.
Rubber micro granules affect water absorption and compress the strength of concrete composite
Authors: Kolendo G , Bajare D , Korjakins A , Sahnmenko G 
Published: January 2023

Abstract

End-of-Life cars and trucks Tyres (ELT) are still an environmental issue around the world and in Latvia. The addition of rubber additives into concrete is quite well-studied worldwide. It is known that the introduction of rubber crumb in large quantities (> 5 % by volume) reduces the mechanical strength of the material and the modulus of elasticity. The results have shown us differences between rubber crumb practical size, and the amount of admixture in concrete. Achieved results clearly showed us the difference between shredded rubber micro granules and disintegrated-like admixture particles to achieve the composite concrete water absorption differences in 0,6 % but compress strength in greater diapason.
Pilot Study on Shrinkage and Fracture of Materials Based on the Alkali-Activated Slag: Influence of Curing Regime
Authors: Kucharczyková B , Šimonová H , Bílek V , Nápravník P 
Published: January 2023

Abstract
The paper presents the results of a pilot study focused on the shrinkage process and fracture parameters of two fine-grained materials prepared from ground granulated blast furnace slag and silica sand. Two different activators were used - liquid sodium silicate and sodium hydroxide. The components ratio and the activator dose were the same for both materials and were as follows: activator dose of 6% Na2O by the slag weight, 1% of lignosulfonate plasticizer, and the ratio of slag:water:sand of 1:0.45:3. All specimens matured at room temperature. For each material, four curing regimes were designed with respect to the potential application on-site (especially different upper surface treatment and demoulding time). The shrinkage measurement lasted more than 2.5 years, after which fracture tests were performed on the same sets of specimens. Although only a slight nuance was in designed curing conditions, the results showed different sensitivity of investigated materials and monitored parameters to the particular curing regimes.
Application of diatomite as a substitute for fly ash in foamed geopolymers
Authors: Brudny Karolina , Łach Michał , Bąk Agnieszka , Pławecka Kinga , Korniejenko Kinga 
Published: January 2023

Abstract
In recent years, new climate targets in EU have led to a growing demand for construction materials with a lower carbon footprint. This implies a demand for research on materials with comparable properties and reduced CO2 emission to replace those currently in use. Geopolymers belong to the group of alkali-activated aluminosilicates, whose advantages include high compressive strength and high corrosion resistance. Examples of aluminosilicate materials used to produce geopolymers are fly ash, metakaolin or volcanic tuff. Recently, there have also been papers discussing the use of diatomite as a replacement for metakaolin in geopolymer materials. The purpose of this work is to investigate the use of diatomite as a fly ash replacement in the production of foamed geopolymers. For this purpose, fly ash based geopolymer samples with different amounts of diatomite (5%, 10%, 50%) were foamed using hydrogen peroxide as a foaming agent. Then, to observe the microstructure of the produced samples, they were subjected to scanning microscope observations. Compressive strength tests according to EN 12390-3 standard were carried out to check the strength properties after 30 days of curing. In addition, the thermal conductivity coefficients of the samples were investigated to better determine their potential industrial application. The expected result is a change in strength and thermal properties with increasing diatomite content.
Foamed geopolymers: a review of recent studies
Authors: Radina L , Sprince A , Pakrastins L , Gailitis R , Sakale G 
Published: January 2023

AbstractUndoubtedly, current environmental trends force scientists to search for a way to reduce carbon dioxide emissions in the production process of building materials. Geopolymers have been called as a potential alternative to traditional concrete for decades, allowing us to obtain more sustainable and durable materials with good thermal and reasonable mechanical properties and solve the problems related to waste materials utilization. Despite the great interest of scientists and the many advantages both in the production process of geopolymers and in terms of material properties, this idea looks unattainable in the near future, so it is worth investigating alternative ways of geopolymer applications.Thereby this review paper summarizes the recent progress in the field of foamed geopolymer concrete, focusing on the different preparation methods, material base, as well as information about the obstacles and challenges that hinder the transition of foamed geopolymers from research laboratories to real application in the civil engineering. This report also describes the density, compressive strength, thermal conductivity, pore size and distribution. A random sampling method and descriptive analysis were used in the preparation of a review, taking into account the year of publication, used materials, availability and the number of citations.
Influence of alkaline activator solution ratio on the properties of biomass fly ash-based alkali-activated materials
Authors: Zhu C J , Pundienė I , Pranckevičienė J , Kligys M , Korjakins A , Vitola L 
Published: January 2023

Abstract
This study explored the use of untreated high-carbon biomass fly ash (BFA) and less alkaline Na2CO3 as an activator to create alkali-activated materials (AAM). This article investigated how the Na2CO3/Na2SiO3 (SC/SS) ratio of the alkaline activator solution (AAS) influenced the setting time, structural development and physical-mechanical properties of BFA-based AAM pastes that were cured at room temperature. With an increase in the SC/SS ratio, AAM pastes’ initial and final setting times shorten, respectively. The AAM sample with the lowest density and ultrasonic pulse velocity (UPV) value also has the maximum water absorption. The compressive strength of AAM samples dropped after 7 days of curing while the SC/SS ratio increased. Nevertheless, after 28 days of curing, the compressive strength of AAM samples rose with a rising SC/SS ratio. The results for density, water absorption, and UPV were corroborated by the scanning electron microscope (SEM) analyses, which demonstrated that when the SC/SS ratio rises, the structure of the samples gets denser and more homogeneous, in line with the increased compressive strength of the samples.
Business processes of digitalization of the agricultural land market in Ukraine
Authors: Skrypchuk P , Shpak H , Skrypchuk V , Gorodyska O 
Published: January 2023

Abstract
The article substantiates the business processes of soil use digitization in order to increase their quality and price in the conditions of the formation of the agricultural land market in Ukraine. For this purpose, environmentally appropriate, socially necessary and economically justified processes have been developed to create synergy in the balance of price and quality of agricultural land. It is proposed to use the ecological audit methodology for these reasons: expert assessment of the quality and price of land; attraction of “green” investments to restore land quality; using the digitization tool - e-calculator. The methodology for building the e-calculator is based on a system of possibilities: obtaining the maximum yield while balancing nutrients in the soil; soil quality improvement under the conditions of planning to obtain the planned harvest with minimal investments; increasing the content of nutrients in the soil to increase the price of agricultural land. The conducted calculations confirm that: preservation and reproduction of the groats fertility guarantees obtaining larger harvests in the future; increases the value of land as the main means of production; increases the investment attractiveness and liquidity of agricultural land. It is substantiated that the costs of carrying out agrochemical measures are profitable investments.
Corporate sustainability reporting and management of agricultural businesses in Ukraine
Authors: Zamlynskyi V , Kryukova I , Vlasenko T , Slutskyi E , Banar O , Anisimova L 
Published: January 2023

Abstract
Meeting the information needs of agribusiness stakeholders based on the implementation of the principles of sustainable development in practice requires appropriate information and analytical support, which is provided by corporate non-financial reporting of economic entities. The purpose of the study is to substantiate the methodological foundations of the construction of the corporate architecture of sustainable management reporting of Ukrainian agricultural companies and to assess the degree of influence of such reporting on the value of agrarian business. The assessment of the degree of influence of corporate reporting of sustainable agricultural management on the financial results and value of agribusiness showed the existence of a close direct connection between agricultural holdings and uncertainty in small agricultural companies. The main problem was identified as the low motivation of the management of medium and small agricultural companies in Ukraine to participate in sustainable development programs. The proposal for the formation of non-financial reporting of an agricultural enterprise has been made, which will help to reveal important information to investors, increase the level of transparency of enterprises and serve as an additional source of forming a positive reputation in the global economic system.
Implementation of the financial monitoring system into the Ukrainian enterprises activity based on the sustainable economic development and green financing concept
Authors: Kushnir N , Los Z , Shpak V , Malanchuk L , Tsaruk D 
Published: January 2023

AbstractThe article provides information on the financial monitoring as a critical control points observation tool, which is implemented to prevent financial stability risks. The connection of the enterprises monitoring system with the directions of the sustainable and green economy goals is characterized. At the internal level, financial monitoring is a prerequisite for the green financing projects realization and is used to evaluate the effectiveness of their implementation. It is stated that the company’s financial monitoring system serves as the instrument of achieving the sustainable development and green economy goals through the production, financial, personnel institutions mechanism and the company’s resource efficiency. Thus, the capital growth and the improvement of enterprise’s value-oriented indicators contribute to the stakeholders benefits and attracts green financing. It should be noted that the State Financial Monitoring Service closely correlates with the national and global sustainable development strategy, it takes into account international recommendations in the combating financial crime. The legislation and financial monitoring system adaptation to risks and compliance with international standards will allow green projects transparency. The article clearly states the place of internal and state financial monitoring in green financing and emphasizes its importance in studying the investment climate for green economy.