bluuebunny/crossref_metadata_2025 huggingface dataset:
Socio-Economic Consequences of Changes in the Tariff Policy of the Electric Power Industry
Authors: Yurkevich Olga
Published: December 2023

The article examines the current tariff policy for electricity in the Republic of Belarus. There has been a significant disproportion in tariffs between industrial and household consumers, including in comparison with the countries of the Eurasian Economic Union and Europe. The level of electricity cost reimbursement, which causes the problem of cross-subsidization, was analyzed. It’s noted that the share of electricity costs in the household budget has been staying at the same level for a long period of time and remains relatively insignificant. It’s noted that with the continued payment of targeted social benefits to pay for housing and communal services for households with low incomes, taking into account the insignificant share of electricity costs in the household budget, the gradual increase in tariff will not have a significant impact on the financial situation of citizens. At the same time, with an increase in energy tariffs, it is necessary to conduct a comprehensive assessment of the growth of household expenses not only in payments for housing and communal services, but also in electricity costs of companies paid by the population as part of domestic goods and services.
Analysing the development of renewable energy sources in European countries
Authors: Zoryna Tatsiana , Matyushenko Angelina
Published: December 2023

This article investigates different types of electricity generation in European countries. The authors examined the trends of renewable electricity generation in Northern, Southern, Western and Eastern Europe. A cluster analysis was performed based on the factors that may predetermine the possibility of using different types of electricity generation: the level of economic development, the amount of air pollutant emissions and the level of energy reserves. Multiple discriminant analysis was used to test the hypothesis that each cluster is characterised by a specific direction. The dependent variable was the country's membership in the clusters, and the independent variables were the types of electricity generation used by the countries: thermal power generation (oil refinery products, gas, coal), nuclear power, hydropower, wind power, solar power, and bioenergy.
Assessment of the energy systems resilience using artificial intelligence methods
Authors: Massel Liudmila , Massel Aleksey , Gaskova Daria , Uzbekov Mirsoli
Published: December 2023

Recently, in Western Europe, a direction defined by the term “Resilience” has been of great interest. Issues of energy and environmental security are of great importance in resilience research. The article discusses an approach to assessing the resilience of energy systems within the framework of the concept of situational management. It is proposed to use artificial intelligence methods: semantic (cognitive) modeling and machine learning. The choice of LSTM as a machine learning model is justified. A method for qualitative and quantitative assessment of the resilience of energy systems has been developed. An example of this method application o assess the resilience of the electric power system of the Siberian Federal District (Russia) in low-water conditions at the Angara-Yenisei cascade of hydroelectric power stations is given.
College students’ potential purchase intention of electric two-wheeled vehicles
Authors: Jou Rong-Chang , Lai Chih-Hung , Chen Tzu-Ying
Published: December 2023

Due to the rise of renewable energy/green energy issues in recent years, many countries have agreed to adopt the forms of environmental protection, cleanliness, and no impact on the environment for the sources and composition of energy. They have also drawn up relevant international agreements (i.e., Kyoto Protocol, Paris Agreement) to strictly limit and manage CO2 emissions. The newly advocated electric vehicles have gradually been regarded as a method to improve the environment by all countries. Through the introduction of new electric transport modes, the innovation and reform of the energy structure are promoted, and traditional transportation has also changed. In recent years, Taiwan has promoted the policy of replacing traditional fuel two-wheeled vehicles with electric two-wheeled vehicles (ETWVs), and gradually increased the number of ETWVs in Taiwan by replacing old fuel vehicles and subsidizing the purchase of ETWVs. This study is aimed at college students to explore the important factors that affect their willingness to buy ETWVs. As college students are the first group to buy ETWVs, if their willingness to buy ETWVs can be increased, environmental sustainability may be enhanced. Through a questionnaire designed to investigate the two-wheeled vehicle use preferences of college students in Taiwan, this paper explores the significant factors affecting college students’ purchase of ETWVs. This study applies Logistic Regression and Ordered Logit models, and the results of model estimation show that household income, gender, environmental awareness, recognition of ETWVs, the fuel costs of existing vehicles, number of people in each household, operational efficiency of ETWVs, and subsidy and incentive measures will all positively affect the purchase intention of college students.
Effects of elevated-temperature deposition on the atomic structure of amorphous Ta2O5 films
Authors: Prasai K. , Lee K. , Baloukas B. , Cheng H-P. , Fazio M. , Martinu L. , Mehta A. , Menoni C. S. , Schiettekatte F. , Shink R. , Shyam B. , Vajente G. , Fejer M. M. , Bassiri R.
Published: December 2023

Brownian thermal noise as a result of mechanical loss in optical coatings will become the dominant source of noise at the most sensitive frequencies of ground-based gravitational-wave detectors. Experiments found, however, that a candidate material, amorphous Ta2O5, is unable to form an ultrastable glass and, consequently, to yield a film with significantly reduced mechanical loss through elevated-temperature deposition alone. X-ray scattering PDF measurements are carried out on films deposited and subsequently annealed at various temperatures. Inverse atomic modeling is used to analyze the short and medium range features in the atomic structure of these films. Furthermore, in silico deposition simulations of Ta2O5 are carried out at various substrate temperatures and an atomic level analysis of the growth at high temperatures is presented. It is observed that upon elevated-temperature deposition, short range features remain identical, whereas medium range order increases. After annealing, however, both the short and medium range orders of films deposited at different substrate temperatures are nearly identical. A discussion on the surface diffusion and glass transition temperatures indicates that future pursuits of ultrastable low-mechanical-loss films through elevated temperature deposition should focus on materials with a high surface mobility, and/or lower glass transition temperatures in the range of achievable deposition temperatueres.
Asymptotic analysis of Jeffreys–Newtonian fluids flowing through a composite vertical porous layered channel: Brinkman–Forchheimer model
Authors: Saini Amit Kumar , Chauhan Satyendra Singh , Tiwari Ashish
Published: December 2023

This study examines the flow of a Newtonian fluid enclosed between two non-Newtonian Jeffreys fluids with viscosity that varies with temperature within a composite vertical channel. Including a corotational Jeffreys liquid allows for considering stress dependence on the present deformation rate and its history. The proposed study's framework comprises three distinct regions, wherein the intermediate region governs Newtonian fluid flow under temperature-dependent viscosity. However, the outer layers oversee the flow of Jeffreys fluids within the porous medium, demonstrating temperature-dependent viscosity. The Brinkman–Forchheimer equation is employed to establish the governing equations applicable to both low and high permeabilities of the porous medium. This equation is nonlinear, making it challenging to find an analytical solution. Therefore, the regular and singular perturbation methods with matched asymptotic expansions are applied to derive asymptotic expressions for velocity profiles in various regions. The hydrodynamic quantities, such as flow rate, flow resistance, and wall shear stresses, are determined by deriving their expressions using velocities from three distinct regions. The graphical analysis explores the relationships between these hydrodynamic quantities and various parameters, including the Grashof number, Forchheimer number, viscosity parameter, Jeffreys parameter, conductivity ratio, effective viscosity ratio, absorption ratio, and the presence of varying thicknesses of different layers. An interesting finding is that a more pronounced velocity profile is noticed when the permeability is high and the viscosity parameter of the Newtonian region, denoted as α2, is lower than that of the surrounding area. This heightened effect can be linked to a relatively more significant decrease in the viscosity of the Jeffreys fluid, represented by μ1, as compared to the viscosity of the Newtonian fluid, μ2, as the temperature increases. The outcomes of this research hold special significance in situations like the extraction of oil from petroleum reserves, where the oil moves through porous layers with varying viscosities, including sand, rock, shale, and limestone.
SiV center electroluminescence in high current density diamond p-i-n diode
Authors: Lobaev M. A. , Radishev D. B. , Vikharev A. L. , Gorbachev A. M. , Bogdanov S. A. , Isaev V. A. , Kraev S. A. , Okhapkin A. I. , Arhipova E. A. , Demidov E. V. , Drozdov M. N.
Published: December 2023

The study of the electroluminescence of silicon vacancy color centers (SiV centers) in the diamond p-i-n diode at high current density of 500 A/cm2 is presented. To create color centers, the internal region of the diode was doped with silicon. In the electroluminescence spectrum, the bright emission line at 738 nm corresponding to the SiV color center in a negative charge state was observed. Such bright emission is due to high current density. Additionally, the 946 nm line corresponding to the emission of the color center in a neutral charge state was observed in electroluminescence. Nanosecond voltage pulses were applied to study electroluminescence in a pulsed regime. Short emission pulses at 738 nm were demonstrated, showing the potential of creating electrically driven single photon source with “photon on demand” capability. By comparing the intensities of photoluminescence and electroluminescence, the possibility of obtaining single photon emission rate in a diode exceeding 106 photon/s is shown.
Aerodynamic performance study of propellers for Mars atmospheric environment
Authors: Zhang Wangwang , Xu Bin , Xiang Changle , Yao Zhaopu , Zhang Haitao , Fan Wei , Zhao Zhiran , Hu Yu
Published: December 2023

In terms of flight conditions, the Martian atmospheric environment is undoubtedly much harsher than the Earth atmospheric environment, with extremely low air density, ultra-low Reynolds number, and raging Martian sandstorms, all of which have serious impacts on the design of Martian unmanned aerial vehicles (UAVs), especially for the design of the power system. The purpose of this paper is to study the impact of the Martian atmospheric environment on the aerodynamic performance of the propeller system. The computational fluid dynamics numerical simulation was used to study the impact of varying degrees of sand and dust accumulation on the aerodynamic performance of Martian propellers caused by Martian sandstorms and widespread dust. It was found that in the Martian atmospheric environment, the rough surface of propeller blades after sand and dust accumulation has better aerodynamic performance than the smooth surface, which is greatly different from the Earth environment; The aerodynamic characteristics of the propeller are tested in the simulated Martian atmosphere vacuum chamber environment, and the experiment has shown that the propeller has better aerodynamic performance under the condition of 8° angle of attack; under the condition of 8° angle of attack, the aerodynamic performance of the propeller is simulated by different Reynolds numbers and different Mach numbers, so as to obtain the influence of the Reynolds number and the Mach number on lift–drag characteristics under the Martian atmospheric environment, and then, the modified blead element theory suitable for the Martian atmospheric environment is derived, which provides a detailed reference for the accurate modeling of the Mars UAV. It has important guiding significance for the design of flight controller.
p53 deficient breast cancer cells reprogram preadipocytes toward tumor-protective immunomodulatory cells
Authors: Hassin Ori , Sernik Miriam , Seligman Adi , Vogel Felix C. E. , Wellenstein Max D. , Smollich Joachim , Halperin Coral , Pirona Anna Chiara , Toledano Liron Nomi , Caballero Carolina Dehesa , Schlicker Lisa , Salame Tomer-Meir , Sarusi Portuguez Avital , Aylon Yael , Scherz-Shouval Ruth , Geiger Tamar , de Visser Karin E. , Schulze Almut , Oren Moshe
Published: December 2023

The
TP53
gene is mutated in approximately 30% of all breast cancer cases. Adipocytes and preadipocytes, which constitute a substantial fraction of the stroma of normal mammary tissue and breast tumors, undergo transcriptional, metabolic, and phenotypic reprogramming during breast cancer development and play an important role in tumor progression. We report here that p53 loss in breast cancer cells facilitates the reprogramming of preadipocytes, inducing them to acquire a unique transcriptional and metabolic program that combines impaired adipocytic differentiation with augmented cytokine expression. This, in turn, promotes the establishment of an inflammatory tumor microenvironment, including increased abundance of Ly6C+ and Ly6G+ myeloid cells and elevated expression of the immune checkpoint ligand PD-L1. We also describe a potential gain-of-function effect of common p53 missense mutations on the inflammatory reprogramming of preadipocytes. Altogether, our study implicates p53 deregulation in breast cancer cells as a driver of tumor-supportive adipose tissue reprogramming, expanding the network of non-cell autonomous mechanisms whereby p53 dysfunction may promote cancer. Further elucidation of the interplay between p53 and adipocytes within the tumor microenvironment may suggest effective therapeutic targets for the treatment of breast cancer patients.
The hydrogen-bonding dynamics of water to a nitrile-functionalized electrode is modulated by voltage according to ultrafast 2D IR spectroscopy
Authors: Ryan Matthew J. , Yang Nan , Kwac Kijeong , Wilhelm Kiera B. , Chi Benjamin K. , Weix Daniel J. , Cho Minhaeng , Zanni Martin T.
Published: December 2023

We report the hydrogen-bonding dynamics of water to a nitrile-functionalized and plasmonic electrode surface as a function of applied voltage. The surface-enhanced two-dimensional infrared spectra exhibit hydrogen-bonded and non-hydrogen-bonded nitrile features in similar proportions, plus cross peaks between the two. Isotopic dilution experiments show that the cross peaks arise predominantly from chemical exchange between hydrogen-bonded and non-hydrogen-bonded nitriles. The chemical exchange rate depends upon voltage, with the hydrogen bond of the water to the nitriles breaking 2 to 3 times slower (>63 vs. 25 ps) under a positive as compared to a negative potential. Spectral diffusion created by hydrogen-bond fluctuations occurs on a ~1 ps timescale and is moderately potential-dependent. Timescales from molecular dynamics simulations agree qualitatively with the experiment and show that a negative voltage causes a small net displacement of water away from the surface. These results show that the voltage applied to an electrode can alter the timescales of solvent motion at its interface, which has implications for electrochemically driven reactions.
Discourse markers in Spanish in the Tijuana-San Diego border area
Authors: Mata R. , Moore John
Published: December 2023

This study examines the use of discourse markers among speakers of Spanish residing in Tijuana, Mexican immigrants
in San Diego, and heritage Spanish speakers in San Diego. We find a core set of discourse markers that is common to all speakers,
as well as subsets of discourse markers for Tijuana, San Diego immigrant, and San Diego heritage speakers. Four English discourse
markers are attested in the border: okay as a general, established borrowing; so only among
immigrant and heritage speakers; and like and you know only among heritage speakers. In a
language-contact situation, discourse markers whose lexical content is less analyzable and whose functions are more operational
detach first from the pragmatically-dominant language (Matras 1998). We find that the
operational properties of okay, like, and you know make them borrowable into the Spanish of the
border. However, so is borrowed in San Diego with operational and content-related features by heritage speakers,
and with content-related features only by immigrant speakers.
Bread 41 Bakery: Minimizing Waste and the Food Waste Hierarchy
Authors: Dodds Rachel
Published: December 2023

Eoin Cluskey had a passion for sustainability but knew it took more than one person to make a difference. Bread 41 is an organic bakery located in Dublin’s inner city whose vision is ‘to create a movement that reaches into every community throughout the island of Ireland’. With a purpose based on sustainability principles that aim to have their customers eat real bread and appreciate real hand-crafted pastries, Bread 41’s goal was to drive exceptional hospitality in a sustainable way.

Information

© The Authors 2023
Virtual Area Guide Training program in Sri Lanka
Authors: Pathirana M.T. , Scott N. , Ekanayake M.P.
Published: December 2023

This case study examines the transformation of Sri Lanka’s tourism industry through a pioneering Virtual Area Guide Training Program, fostering sustainability in challenging times.

This case study explores the innovative Virtual Area Guide Training Program conducted in Sri Lanka in 2022, aimed at transforming the tourism sector from informal to formal, enhancing sustainability. In the face of challenges like terrorism, the pandemic, and an economic crisis, the program selected and trained 20 individuals from the underdeveloped Uva province as tour guides. The unique program, conducted virtually, integrated academic and industry expertise to equip participants with essential skills and licenses. The participants’ success in work-integrated learning and their transition to becoming licensed tour guides highlight the program’s impact. The case study recommends policies that promote long-term sustainability and inclusivity in the tourism industry, emphasizing the importance of contextualizing solutions for local communities.

Information

© The Authors 2023
A robust GNSS sensors in presence of signal blockage for USV application
Authors: Liu Wei , Huang Hua , Hu Yuan , Han Bing , Wang Shengzheng
Published: December 2023

Unmanned surface vehicle (USV) can navigate autonomously via the global navigation satellite system (GNSS). However, the traditional GNSS scalar tracking loop easily loses lock in low carrier-to-noise ratio (CNR) situations, such as signal occlusion and weak signals. Meanwhile, an increase in the carrier/code phase error leads to an increase in the measurement error of the navigation filter, which decreases the accuracy of the position estimation. To solve this problem, this paper proposes a carrier and code tracking structure based on a forward and backward Kalman filter to dynamically adjust the gain of the vector tracking loop. The carrier and code phase errors calculated by the loop discriminators were linearly transformed into pseudo-range rate and pseudo-range errors after filtering and smoothing, which were used as the measurements of the navigation filter. The signal CNR was used to adaptively adjust the measurement noise covariance matrix of the loop filters. The field tests used a commercial receiver’s navigation solution as the reference. In the stationary test, the proposed structure reduced the localization error by 44.3% compared with the traditional methods. In kinematic experiments, the proposed structure reduced the carrier and code phase errors in a harsh signal environment and improved the positioning accuracy at the source. The test results demonstrate that the proposed GNSS tracking method can provide a possible solution for the development of navigation systems for USV.
A novel 6-dimensional force measurement based on the electric 6-DOF loading device
Authors: Sang Yong , Liao Lianjie , Chen Tao , Liu Jiakuo
Published: December 2023

The 6-degrees-of-freedom (6-DOF) platform has gained popularity in industry owing to its advantages, especially in indoor simulation experiment requiring six-dimensional force environments. However, up to date, the measurement of such six-dimensional forces is challenging due to complex structures, difficult decoupling, and high costs. In this study, an electric 6-DOF loading device designed by ourselves is presented, with an ability to load high precision displacement and force. To measure the six-dimensional force of the device’s moving platform, this paper proposes a scheme involving embedding tension-compression sensors in each leg of the device and describes the mechanical model of the device. Then a novel method with a variable transformation matrix is proposed, complemented by a decoupling study that optimizes the variable transformation matrix. Finally, we validate the proposed method through an external force loading experiment. The results indicate that the error in Fy experiment is less than 2.7%, and the error in Fz experiment is less than 1.6%. The novel method exhibits high accuracy, easy installation, fast response, and low cost.
The Abrupt Resumptions of Pulsations in α Cygni (Deneb)
Authors: Abt Helmut A. , Guzik Joyce A. , Jackiewicz Jason
Published: December 2023

Paddock’s 1927–1935 radial velocities of α Cygni (Deneb) show semi-regular pulsations with a dominant period of about 12 days. Lucy found many periods of lesser amplitude. In Paddock’s data and subsequent 1956 data from Abt, after the large-amplitude pulsations seemed to damp down, abruptly new sets of pulsations started within a fraction of a day. Five of those resumptions occurred with intervals averaging 72.4 ± 0.3 days. These resumptions seem to start at any phase during the pulsations. We are unaware of this behavior in any other star. We also find evidence of this behavior in the 1977–1982 radial velocity data of Parthasarathy & Lambert and the 1997–2001 photometry/radial velocity data of Richardson et al., as well as in photometric data from the NASA Transiting Exoplanet Survey Satellite (TESS) spacecraft and ground-based visual observations in the AAVSO International Database. The ground-based data have too infrequent sampling intervals to confirm the ∼70-day resumption intervals or to pinpoint the day and phase of abrupt amplitude increase. The TESS data, with 2-minute cadence, shows one instance of pulsation resumption, but does not have a long enough time series to confirm a ​​​​​70-day interval. Without any evidence for duplicity, we cannot explain this behavior as being due to a companion in a highly eccentric orbit. α Cygni is one of the Luminous Blue Variables (supergiants) and these resumptions may be related to the microvariations produced in convective layers below their atmospheres, pulsation-driven shocks and rarefactions, or pulsation-convection interactions. We encourage further observations by ground-based observers and using the TESS spacecraft to confirm the ∼70-day resumption interval and lack of correlation with pulsation phase in both radial velocity and light curve data.
Towards user-centric BCI design: Markov chain-based user assessment for mental imagery EEG-BCIs
Authors: Ivanov Nicolas , Lio Aaron , Chau Tom
Published: December 2023

Objective. While electroencephalography (EEG)-based brain–computer interfaces (BCIs) have many potential clinical applications, their use is impeded by poor performance for many users. To improve BCI performance, either via enhanced signal processing or user training, it is critical to understand and describe each user’s ability to perform mental control tasks and produce discernible EEG patterns. While classification accuracy has predominantly been used to assess user performance, limitations and criticisms of this approach have emerged, thus prompting the need to develop novel user assessment approaches with greater descriptive capability. Here, we propose a combination of unsupervised clustering and Markov chain models to assess and describe user skill. Approach. Using unsupervised K-means clustering, we segmented the EEG signal space into regions representing pattern states that users could produce. A user’s movement through these pattern states while performing different tasks was modeled using Markov chains. Finally, using the steady-state distributions and entropy rates of the Markov chains, we proposed two metrics taskDistinct and relativeTaskInconsistency to assess, respectively, a user’s ability to (i) produce distinct task-specific patterns for each mental task and (ii) maintain consistent patterns during individual tasks. Main results. Analysis of data from 14 adolescents using a three-class BCI revealed significant correlations between the taskDistinct and relativeTaskInconsistency metrics and classification F1 score. Moreover, analysis of the pattern states and Markov chain models yielded descriptive information regarding user performance not immediately apparent from classification accuracy. Significance. Our proposed user assessment method can be used in concert with classifier-based analysis to further understand the extent to which users produce task-specific, time-evolving EEG patterns. In turn, this information could be used to enhance user training or classifier design.
Degree of differentiation impacts neurobiological signature and resistance to hypoxia of SH-SY5Y cells
Authors: Voogd E J H F , Doorn N , Levers M R , Hofmeijer J , Frega M
Published: December 2023

Objective. SH-SY5Y cells are valuable neuronal in vitro models for studying patho-mechanisms and treatment targets in brain disorders due to their easy maintenance, rapid expansion, and low costs. However, the use of various degrees of differentiation hampers appreciation of results and may limit the translation of findings to neurons or the brain. Here, we studied the neurobiological signatures of SH-SY5Y cells in terms of morphology, expression of neuronal markers, and functionality at various degrees of differentiation, as well as their resistance to hypoxia. We compared these to neurons derived from human induced pluripotent stem cells (hiPSCs), a well-characterized neuronal in vitro model. Approach. We cultured SH-SY5Y cells and neurons derived from hiPSCs on glass coverslips or micro-electrode arrays. We studied expression of mature neuronal markers, electrophysiological activity, and sensitivity to hypoxia at various degrees of differentiation (one day up to three weeks) in SH-SY5Y cells. We used hiPSC derived neurons as a reference. Main results. Undifferentiated and shortly differentiated SH-SY5Y cells lacked neuronal characteristics. Expression of neuronal markers and formation of synaptic puncta increased during differentiation. Longer differentiation was associated with lower resistance to hypoxia. At three weeks of differentiation, MAP2 expression and vulnerability to hypoxia were similar to hiPSC-derived neurons, while the number of synaptic puncta and detected events were significantly lower. Our results show that at least three weeks of differentiation are necessary to obtain neurobiological signatures that are comparable to those of hiPSC-derived neurons, as well as similar sensitivities to metabolic stress. Significance. This indicates that extended differentiation protocols should be used to study neuronal characteristics and to model brain disorders with SH-SY5Y cells. We provided insights that may offer the basis for the utilization of SH-SY5Y cells as a more relevant neuronal model in the study of brain disorders.
Pedestal main ion particle transport inference through gas puff modulation with experimental source measurements
Authors: Rosenthal A.M. , Hughes J.W. , Laggner F.M. , Odstrčil T. , Bortolon A. , Wilks T.M. , Mordijck S. , Miller M.A. , Sciortino F.
Published: December 2023

Transport in the DIII-D high confinement mode (H-mode) pedestal is investigated through a periodic edge gas puff modulation (GPM) which perturbs the deuterium density and source profiles. By using absolutely calibrated experimental edge ionization profile measurements, radial profiles of diffusion (D) and convection (v) are calculated into the pedestal region without depending on modeling the edge ionization source. An analytic approach with closed-form expressions for the D and v profiles and a more advanced Bayesian approach show evidence of an inward particle convection on the order of 1 m s−1 extending to normalized poloidal flux (

Ψ

N

) of 0.98. Meanwhile, diffusion reaches a minimum value of

(
0.03
±
0.02
)

 m2 s−1 in the pedestal region. Notably, the Bayesian approach, which utilizes the Aurora 1.5 D forward model inside the IMPRAD OMFIT module, provides radially resolved transport profiles with associated uncertainty without requiring an explicit form for the perturbation to the density profile or source. The combination of experimental ionization measurements and Bayesian inference provides an enhanced robust framework for investigating edge particle transport coefficients to experimentally test transport physics in order to improve predictive capabilities in the tokamak edge.
Asymptotic behaviour of the non-oscillating solutions of first order nonlinear impulsive functional-differential equations of neutral type
Authors: Donev V I
Published: December 2023

This paper deals with nonlinear first-order impulsive functional-differential equations of neutral type with variable coefficients. The asymptotic behaviour of the non-oscillating solutions of such equations is investigated as a function of the values of the variable coefficient in the neutral term to serve as a basis for further studies of the oscillation of the solutions of such equations.
Approximate Analytical Solution for Turbulent Flow in Channel
Authors: Fedoseyev Alex
Published: December 2023

In this work, the approximate analytical solutions of the Generalized Hydrodynamic Equations (GHE) for turbulent flow in channel is presented. The general solution is a superposition of the laminar (parabolic) and turbulent (superexponential) solutions. The analytical solution compares well with the experimental data by Van Doorne (2007) and Nikuradse (1933).

It is proposed to explain the nature of turbulence as oscillations between the laminar (parabolic) and turbulent (superexponential) solutions. The suggestion is confirmed by comparing the results for turbulent velocity fluctuations of the analytical formula with the experiment by Van Doorne (2007). The Navier-Stokes equations do not have the superexponential solution.

The obtained analytical solution provides a complete structure of the turbulent boundary layer that compares well with the experiments by Wei and Willmarth (1989).
An application of some machine learning methods for biological data modeling
Authors: Sapundzhi Fatima , Lazarova Meglena , Dzimbova Tatyana , Georgiev Slavi
Published: December 2023

The development of fast and reliable methods for predicting the biological activity of the substances in computational biology is of a great importance. This improves the development of some new compounds while keeping costs low. Among many scientists, an attractive target for docking experiments is the Delta-opioid receptor (DOR) and delta-opioid ligands (DOL). Their biological efficacy can be measured by various techniques, which could facilitate the establishment of the relationship between the structure of the compounds and their biological effect. The relationship between the results of the computer experiments and the biological activity of these compounds is modelled by using machine learning regressors. The primary goal of this study is to determine the most appropriate neural network for modelling the relationship between in vitro and in silico results for DOR and delta-opioid ligands.
Moving iso-contour method for solving partial differential equations
Authors: Pohjonen Aarne
Published: December 2023

The numerical solution of partial differential equations is often performed on a numerical grid, where the grid points are used for estimating the partial derivatives. The grid can be fully static as in Eulerian type of solution method, or the grid points can move during the solution, which is the case in Lagrangian type of method. In the current article, a numerical solution method is presented, where the grid points are located on iso-contours of the two-dimensional field. The method calculates the local movement of the iso-contours according to an evolution equation described by the PDE, and the solution proceeds by moving the grid points towards the calculated direction. Additional stability is obtained by setting the grid points to move along the iso-contour line. To exemplify the application of the method, numerical examples are calculated for the two-dimensional diffusion equation.
DFT techniques for resolution of significant practical materials problems
Authors: Alarco J A , Mackinnon I D R
Published: December 2023

Significant examples are presented on the capacity to predict properties of practical materials and to understand fundamental properties by informed use of Density Functional Theory (DFT) computational techniques. An example in the field of battery materials, involves understanding surface phenomena via a combination of multiple experimental techniques and DFT calculations of electronic band structures (EBS). This approach delivered significantly improved cycle life of battery cathode materials. Another example is from the field of superconductivity. In this case, analysis of results from advanced experimental techniques, interpreted with the assistance of DFT calculations, reveals that crystal symmetries of superconductors are different to the general space group symmetry routinely used. The insight on fundamental properties gained from precise DFT calculations is unparalleled and accelerates research progress. The importance of calibration that enables accurate and realistic DFT approaches to modelling, combined with regular experimental validation, cannot be overstated.
Acoustic monitoring humidity effects on the formation of water bridges at sharp contacts
Authors: Supichayanggoon Kacharat , Brockman Theodore , La Rosa Andres H
Published: December 2023

Shear-force Acoustic Near-field Microscopy (SANM) and Whispering Gallery Acoustic Sensing (WGAS) are used to evaluate the role of humidity on the formation and rupture of water meniscus bridges that form between a laterally oscillating tapered probe and a flat substrate. SANM monitors the near-field acoustic wave emitted by the meniscus, while WGAS monitors acoustically the probe’s amplitude of oscillation, as a function of the probe-sample distance. In the instances reported here, the SANM/WGAS measurements are performed in frequency modulation modality, which allows to discriminate the elastic and inelastic components of the probe-fluid-substrate interaction. The response signal traces, acquired when the probe first approaches and then retracts from the sample at 56% relative humidity (or below), revealed absence of hysteresis; this result persists when performing the same experiment a few days later. However, as the humidity increases (different trials from 56% to 67% are included) a notorious hysteresis is observed between the approach and retraction traces. The results indicate that, as the probe approaches the substrate, a higher humidity promotes an increase of stochastic instabilities in the probe-fluid-substrate interactions (reflected in higher damping effects on the probe, and instabilities in the probe-sample distance feedback control). However, the elastic response of the water meniscus prevails over damping effect, as revealed by the greater acoustic emission despite a decrease in the probe’s amplitude. These measurements are relevant to investigations on the dynamic behavior of fluids near hydrophobic/philic substrates, and wetting properties of solids and nanotribology phenomena in general.
Geant4 simulation study of low-Z material detection using muon tomography
Authors: Georgadze Anzori Sh. , Kudryavtsev Vitaly A.
Published: December 2023

Traditional X-ray scanning systems for cargo use ionising radiation which can be harmful
to operators and the environment and requires shielding. Fully passive muon tomography is a
promising alternative or a complementary approach to X-ray scanners. Muon tomography is a
non-invasive technique that uses naturally occurring cosmic-ray muons and their scattering in
various materials to create images of cargo in trucks or containers without applying ionising
radiation. Muons are high-energy particles that are produced when primary cosmic rays collide with
the Earth's atmosphere. These muons can penetrate through thick materials, such as concrete or
metal, and are therefore useful for detecting hidden objects, including contraband. Muon
tomography is expected to be used for detection of a wide range of materials, including metals,
plastics, and organic materials like drugs or cigarettes, as well as weapons and explosives. In
this work we have used the GEANT4 toolkit to simulate the performance of muon tomography in
identifying the contraband hidden inside the legal cargo. We have used the Point of Closest
Approach (PoCA) reconstruction algorithm to reconstruct the three-dimensional image of a loaded
truck.
A high throughput Intrusion Detection System (IDS) to enhance the security of data transmission among research centers
Authors: Grossi M. , Alfonsi F. , Prandini M. , Gabrielli A.
Published: December 2023

Data breaches and cyberattacks represent a severe problem in higher education institutions
and universities that can result in illegal access to sensitive information and data loss. To
enhance the security of data transmission, Intrusion Prevention Systems (IPS, i.e., firewalls) and
Intrusion Detection Systems (IDS, i.e., packet sniffers) are used to detect potential threats in
the exchanged data. IPSs and IDSs are usually designed as software programs running on a server
machine. However, when the speed of exchanged data is too high, this solution can become
unreliable. In this case, IPSs and IDSs designed on a real hardware platform, such as ASICs and
FPGAs, represent a more reliable solution. This paper presents a packet sniffer that was designed
using a commercial FPGA development board. The system can support a data throughput of 10 Gbit/s
with preliminary results showing that the speed of data transmission can be reliably extended to
100 Gbit/s. The designed system is highly configurable by the user and can enhance the data
protection of information transmitted using the Ethernet protocol. It is particularly suited for
the security of universities and research centers, where point-to-point network connections are
dominant and large amount of sensitive data are shared among different hosts.
Antibacterial Activities of Heterotrigona itama Honey Farmed in Ex-Mining Area
Authors: Ardy A T K O , Arung E T , Yuliansyah
Published: December 2023

Honey is considered to be a valuable non-timber forest product due to its numerous preventative and therapeutic properties. The nutritional content in honey is the most complete so it can boost the immune system. This study aims to determine the potential inhibition of Heterotrigona itama stingless bee honey against the activity of Staphylococcus sp bacteria and Propionibacterium sp bacteria. This research adopted the agar diffusion method to conduct antibacterial testing. The nutrient agar media was aseptically put into a sterile petri dish and thereafter left to air-dry. Following this, the bacterial suspension was reconstituted and subsequently inoculated onto the solidified agar surface by creating perforations. The experiment involved conducting antibacterial tests using many concentrations of the samples. The experimental setup included a positive control using chloramphenicol and a negative control using distilled water. The test results showed that the activity of the inhibition of Heterotrigona itama kelulut honey against Staphylococcus sp bacteria and Propionibacterium sp bacteria belonged to the strong antibacterial category. The antibacterial activity of honey exhibits an enhanced potency against both types of bacteria in direct proportion to the content of the honey sample.
Antimicrobial, antioxidant and phytochemical activities of three orangutan plant foods in Wehea-Kelay Landscape, East Kalimantan
Authors: Ibrahim  , Rosamah E , Hendra M , Sudiono E , Rifqi M A , Kusuma I W
Published: December 2023

The Bornean orangutan (Pongo pygmaeus) is an umbrella species with a high population in the Wehea-Kelay Landscape. In this landscape, at least 227 forage plant species have been identified as potential medicine plants including Eusideroxylon zwageri, Nephelium lappaceum, and Tristaniopsis whiteana. The aim of this study was to determine the yield value of extracts produced from three different plant samples, qualitatively and quantitatively trace the phytochemical content, as well as test the antioxidant and antimicrobial activities. In this study, Qualitative phytochemical assays were conducted by observing the presence of colour changes. Quantitative analysis of phytochemicals was conducted using the colorimetric test method. The assessment of antioxidant activity involves the utilisation of the DPPH radical decolorization test method. An antimicrobial test was performed at a concentration of 62,5–500 µg/well with chloramphenicol and miconazole as positive controls. The qualitative phytochemical examination revealed the presence of alkaloid, flavonoid, tannin, triterpenoid, carbohydrate, carotenoid, and coumarin components in three samples. The quantitative phytochemical analysis revealed that the plant samples possessed a total phenolic content ranging from 2,397 to 4,163 µg GAE/mg extract. The plant samples were analysed and found to have a total flavonoid content ranging from 4,493 to 5,557 µg CE/mg extract. The plant samples demonstrated potent antioxidant activity, effectively inhibiting free radicals. The IC50 values ranged from strong to extremely strong. Antimicrobial testing on medicinal plant extracts provides weak to strong inhibition.
Restoring ex mining area using Pongamia pinnata in Central Kalimantan: a reclamation program alternative base on bioenergy species
Authors: Maimunah S , Erdhani S , Suwito SB , Rawana  , Lestari NS , Leksono B , Himlal B
Published: December 2023

Malapari (Pongamia pinnata (L) Pierre) is an endemic species of Leguminosae from southeast Asia, Australia and Afrika. Malapari is one species alternative of Reclamation Program in PT Asmin Bara Bronang. The aims of this study are to know the growth and adaptation rate of Malapari in extrime area after charcoal mining and to introduce the malapari for a alternative species for reclamation program with bioenergy potential species. The research method used is the census method in areas planted with malapari at PT ABB which was observed from 2020 with parameters including malapari growth; survival rate; analysis of soil fertility; biodiversity and carbon estimate. The results showed that malapari growth on post-mining land was very rapid where within 4 years it increased in height by an average of 184,92cm with a diameter growth of 10.76 cm and a survival rate of 87,78%, above ground biomass 584,04kg (274,5kg carbon) with very good leaf growth in fresh dark green The condition of early soil fertility becomes increased after planting. The great hope in this program is that malapari can be an alternative species for post-coal mining forest restoration from local superior species of use that has the potential to be a bioenergy source.
Early Growth of Seven Local Tree Species In The Reclamation Area of PT Bara Tabang
Authors: Adman Burhanuddin , Iriyanto Yustinus , Yassir Ishak , Wahyudin  , Laban Banjar Y. , Trisnardono Rudiro , Adityawan Yustinus
Published: December 2023

Revegetation of post-mining land with local species has been carried out by coal mining companies in East Kalimantan. However, the information about plant species that can adapt to post-mining land environments is still limited. Therefore, PT Bara Tabang, as a coal mining company, has established a demonstration plot for planting local species in post-coal mining areas. The purpose is to add information on local species that can adapt to the post-mining environment. There were 7 species planted, that is Vitex pinnata, Syzygium polyanthum, Schima wallichii, Shorea balangeran, Melaleuca cajuputi, Syzygium sp., and Hopea mengarawan. 100 plants were planted for each species with the addition of 1 kg of compost for each plant. Observations for six months showed that the survival rate of local species was still above 90%, except for H. mengerawan that only 13%. The species of plants that showed the best growth in height and diameter at 6 months of age were M. leucadendron with 8.08 cm and 0.16 cm respectively. Sc. wallichii showed the lowest growth in height and diameter of 1.60 cm and 0.05 cm respectively at 6 months of age.
Effect of cow urine concentration and NPK fertilizer doses on the growth of oil palm seedlings (Elaeis guineensis Jacq)
Authors: Jamidi  , Zuliati S , Wirda Z
Published: December 2023

Application of anorganic fertilizers can be reduced by using organic fertilizers such as cow biourine. This study aimed to see the combination of cow biourine and anorganic fertilizers (NPK fertilizer) on the growth of oil palm seedlings. Research was conducted at East Reuleut Village, Muara Batu District, and Agriculture Laboratory of Malikussaleh University on April to June 2021 using factorial Randomized Block Design. Concentration of cow biourine consisting 4 levels : control (U0), 50 cc/L (U1), 75 cc/L (U2), and 100 cc/L (U3). Doses of NPK fertilizer consisting 3 levels, control (N0), 2 g/polybag (N1), and 3 g/polybag (N2), each treatment replicated 3 times. Results showed the interaction between application of cow biourine concentration and NPK fertilizer doses increase plant height on 9 WAP, and number of leave on 11 WAP of oil palm seedlings. Single-dose cow biourine increases plant height growth, stem diameter, chlorophyll content, fresh weight and dry weight of oil palm seedlings. NPK fertilizer separately increases plant height growth, leaf chlorophyll of oil palm seedlings. Interaction between 100 cc/liter of cow biourine concentration + 2 grams/polybag of NPK fertilizer dose was the best combination.