bluuebunny/crossref_metadata_2025 huggingface dataset:
High performance n-MoSe2/p-Ge-GeSn MQW/n-Ge heterojunction phototransistor for extended short-wave infrared photodetection
Authors: Wang Rui , Cai Xinwei , Yang Tianwei , Wu Qiang , Ding Haokun , Zhu Yiming , Lin Guangyang , Li Cheng
Published: December 2024

Germanium tin (GeSn) holds great potential for the development of monolithic short-wave infrared (SWIR) photodetectors. However, the large dark current and insufficient responsivity, resulting from the dense surface states and deteriorated crystal quality of high-Sn fraction GeSn thin films, pose significant challenges for their practical application. Herein, a fully strained GeSn-Ge multiple-quantum-well (MQW) bipolar heterojunction phototransistor (HPT) with an n-MoSe2/p-Ge van der Waals (vdW) heterostructure serving as the emitter-base junction is proposed to suppress dark current and enhance responsivity in the SWIR band. The fully strained GeSn-Ge MQWs are strategically employed as the absorption region, thereby extending the response wavelength up to 2000 nm and significantly reducing the dark current density. The developed HPT with a floating base achieves a low dark current density of 7.87 mA cm−2 at 2 V and a commendable responsivity of 1.3 A W−1 at 1550 nm along with rapid rise/fall times of 81.3 μs/73.1 μs. Furthermore, the phototransistor operates in self-powered mode, showcasing a high specific detectivity of 2.6 × 1010 Jones. These results suggest that the proposed GeSn-Ge MQW-based mix-dimensional vdW HPT can effectively suppress dark current and enhance detectivity for advanced SWIR imaging applications.
Swift heavy ion induced electronic structure modifications in ZnO thin films: X-ray absorption spectroscopy study
Authors: Gautam Sanjeev , Verma Monika , Thakur Anup , Chen Jin-Ming , Hwa Chae Keun
Published: December 2024

ZnO is a potential material for electronic device applications due to its versatile semiconducting properties with a direct band gap of 3.3 eV. This research represents a modification in the electronic structure of ZnO thin films (350 nm) irradiated with swift heavy ions (SHI) at different fluences. ZnO thin films were grown on a silicon substrate (100) using radio-frequency magnetron sputtering, which are highly oriented in a single phase/plane (002). The deposited thin films were subjected to SHI of 100 MeV O-ion with fluence of 3×1012 ions cm−2, 45 MeV Li-ion beams with fluence of 3×1012 ions cm−2 and 120 MeV Au-ion with varying fluence from 1×1011 to 5×1012 ions cm−2. SRIM/TRIM software was utilized to study theoretical effects of SHI like ion ranges, phonon energy, etc. Modifications in the structure and the electrical properties of ZnO thin films were investigated using high-resolution X-ray diffraction (HRXRD), Atomic Force Microscopy and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy at the O K- and Zn L

3
,
2

-edges. HRXRD employed for the structure, crystallinity, and phase of the system whereas NEXAFS for the local atom bonding symmetry via the molecular orbital hybridization between Zn and O. Furthermore, Density Functional Theory based on first principles FEFF9.6 has been incorporated for better understanding of NEXAFS while discussing the various parameters and cards. Simulations were performed to support the NEXAFS experimental data for the determination of various physical entities and their interpretations for diverse applications. NEXAFS measurements provide a deeper understanding of the effects of SHI for promising applications through the controlled fluence rate of ion beam irradiations.
C60 fullerene improves the contractile activity of the injured rat muscle gastrocnemius
Authors: Prylutskyy Yuriy , Nozdrenko Dmytro , Motuziuk Olexandr , Prylutska Svitlana , Nurishchenko Natalia , Franskevych Daria , Soroca Vasil , Cherepanov Vsevolod , Kalinin Ihor , Korzhyk Olha , Ritter Uwe
Published: December 2024

The powerful antioxidant properties of C60 fullerenes have been widely used in biomedical nanotechnology. Owing to the negative effects of free radicals in oxidative stress processes, antioxidants are required to protect injured muscles. Here, the effect of water-soluble C60 fullerenes (daily oral dose 1 mg kg−1) on the process of restoration of contractile activity of skeletal muscle of rats (muscle gastrocnemius) 15 d after the initiation of open trauma of different severity was studied for the first time. The structural organization of C60 fullerene nanoparticles in aqueous solution was analyzed by dynamic light scattering and atomic force microscopy techniques. Such biomechanical parameters of muscle gastrocnemius contraction as integrated muscle power, levels of generation of its maximum and minimum force, and time interval until reaching 50% of the level of force response of the muscle were analyzed. Such biochemical indices as concentrations of c-reactive protein, creatinine, and lactate in the rat blood, as well as indices of pro- and antioxidant balance (activities of superoxide dismutase and catalase, the concentration of reduced glutathione) in the blood and muscle tissue of experimental animals, were investigated. It was found that application of water-soluble C60 fullerenes statistically significantly improves biomechanical parameters of contraction of injured muscle gastrocnemius at the level of 30–45 ± 3%, which is confirmed by normalization of biochemical indices in the blood and muscle tissue of rats at the level of 35–50 ± 3% and 20–37 ± 3%, correspondingly, relative to the open injury group. These findings open the possibility of using C60 fullerenes as potential therapeutic nanoagents capable of correcting pathological states of the muscular system during the physiological repair of open injuries.
Preparation of novel B/ZnO/zeolite nanocomposites by simple combustion method for enhanced dye removal in an aqueous environment
Authors: Nguyen Thu Huong , Van Duong Le , Vu Anh-Tuan
Published: December 2024

In this study, the mixture of zinc acetate dehydrates and boric acid was pyrolyzed in zeolite X to prepare novel B/ZnO/zeolite nanocomposites for the enhanced removal of tartrazine (TA) in aqueous environment. The composites are porous material with a relatively large pore size (35.3 nm). The surface area of the composite (19.72 m2 g−1) is smaller than that of zeolite (248.78 m2 g−1), but its adsorption capacity is quite high (q
max of 97.6 mg g−1). The factors influencing the adsorption process were investigated in detail. Under the optimal conditions (the initial dye concentration of 20 mg l−1, the adsorbent content of 0.5 g l−1, pH equal 6, and the temperature of 25

°

C

), the removal efficiency (R
e) was 97.5%. The first and second-order equations were used to model the kinetic adsorption. The Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich models were used to study isothermal adsorption. In addition, the thermodynamic of adsorption was also investigated. The ΔH
o of −52.423

±

2.306 kJ mol−1 indicates the exothermic process and the negative ΔG
o indicates a spontaneous process. At low temperatures, the adsorption of TA proceeds smoother and more effectively, and the negative ΔS
o (−129.638 7.376 J·mol−1·K−1) indicates a decrease in the degree of freedom of the adsorbed species. The adsorption mechanism was also proposed.
A simple and versatile dual-state variable stiffness structure based on microwedge dry adhesives
Authors: Chen Gen , Bao Tingting , Chu Zhongyi , Cui Jing
Published: December 2024

The integration of softness and rigidity underpins the concept of variable stiffness, leveraging the distinct advantages of both properties. Inspired by this concept, this paper introduces a stiffness-switchable composite structure achieved through laminar jamming enabled by the inherent dry adhesion force of microwedge adhesives. This mechanism allows for a reversible transition between high flexibility and pronounced rigidity, achieving a remarkable stiffness ratio of 75, with easier implementation and enhanced functionality. Comprehensive modeling and experimentation are conducted to reveal intricate aspects of the structure’s mechanical properties, such as interlayer behavior and failure processes. This paper also outlines two potential applications for this multifunctional structure: a robotic gripper with dual modes of rigid pinch and compliant adhesion, and an integrated multifunctional sensing setup. The proposed structure might broaden the scope of dry adhesives and laminar jamming structures, suggesting new possibilities for future research and development.
Advanced processing techniques for electric field-guided electrospinning of self-organized Ag nanoparticle electrodes for real-time humidity and temperature sensing
Authors: Aoboun Assareeya , Pechyen Chiravoot , Shin Dong-Youn
Published: December 2024

With the rapid expansion of flexible electronics, there is an urgent need for sustainable production methods that enhance device performance while minimizing environmental impact. This work presents an innovative, green approach for fabricating flexible, patterned electrodes via electric field-driven self-organization of conductive fibers onto flexible substrates. By applying high voltage to both the dispensing nozzle and an underlying printed circuit board substrate, the system leverages controlled electric fields to direct fiber jets with precision, eliminating the need for conventional masking techniques. The fiber composition-polyethylene oxide integrated with silver nanoparticles-provides both conductivity and environmental compatibility. This streamlined technique notably reduces material usage, processing time, and chemical waste. Practical demonstrations involve the construction of flexible conductive electrodes for humidity and temperature sensors, achieving a low sheet resistance near 10 Ω sq−1, attesting to the method’s functional viability. The process ensures precise fiber alignment and consistent deposition, paving the way for its integration into flexible sensor and device applications. This study underscores the potential of electric field manipulation to revolutionize coating processes for sustainable and scalable production in flexible electronics.
Modeling of shear wave propagation in piezo-viscoelastic microbeam over quadratic heterogeneous viscoelastic plate with sliding contact
Authors: Sadab Mohd , Kundu Santimoy
Published: December 2024

This study analyzes the phase and attenuation dynamic behavior of piezo-viscoelastic microbeam overlying quadratic heterogeneous viscoelastic plate under sliding contact. Using the Kelvin–Voigt model, the material properties of the system are assumed to be viscoelastic. Maxwell’s relations are used to incorporate the electric potential function. The solutions for both media are derived separately by solving the second-order hyperbolic differential equation using the method of separation of variables and expansions of Bessel functions. The system of linear homogeneous equations is obtained by applying admissible boundary conditions to determine fundamental physical quantities. The key contribution of the current work is demonstrating the influence of dissipation factors, sliding contact, micro-length, heterogeneity, and thickness ratio parameters on shear wave propagation. The micro-length effect is found to suppress the attenuation of shear waves through the analysis and discussion of the dispersion and attenuation curves.
Radiation protection: assessing the shielding performance of iron-reinforced polydimethylsiloxane in comparison to lead
Authors: Yazdankish Enayatolah , Nejatolahi Mostafa , Ghobadpouri Saeed
Published: December 2024

This study evaluates the radiation shielding properties of Polydimethylsiloxane reinforced with iron. Using the Py-MLBUF program, we calculated and compared the mass attenuation coefficient, linear attenuation coefficient, half-value layer, effective atomic number, and effective electron number with those of lead. The dominance of the photoelectric effect at lower energies and pair production at higher energies is observed. The contribution of Compton scattering remains relatively constant across the energy spectrum, while Rayleigh scattering is negligible. At lower energy levels, composites reinforced with higher iron weight fractions demonstrate higher mass attenuation and linear attenuation coefficients. Increasing iron weight fractions reduces the half-value layer, improving radiation attenuation up to a threshold. The results show that while lead generally has higher attenuation coefficients, the difference is negligible at energies between 0.7 and 4 MeV. Although lead has lower half-value and tenth-value layers, higher iron weight fractions in PDMS also, provide good radiation shielding due to increased effective atomic and electron numbers. Fe-reinforced PDMS at weight fractions of 10%, 20%, 40%, and 60% show significant potential for radiation shielding, especially in the 0.7 to 4 MeV photon energy range, and in applications requiring flexibility and lightweight materials.
Synthesis and characterization of corn cob activated carbon for Pb(II) adsorption with real-time monitoring using internet of things
Authors: Muh Amar Masyhudul Haq , Tahir Dahlang , Heryanto Heryanto , Abdelilah Akouibaa , Alomari Ali , Setiawan Vicram , Putri Suriati Eka
Published: December 2024

Here, we investigate the adsorption of Pb(II) using AC derived from corn Rachis (RAC) with various carbonization temperatures: 500 °C, 700 °C, and 900 °C using KOH solution as the activator. Fourier Transform Infrared Spectroscopy (FTIR) analysis revealed the presence of hydroxyl and carbonyl functional groups and optical-dielectric function change under the carbonization process. X-ray Diffraction (XRD) patterns confirmed the presence of (002) and (100) lattice planes, indicating a graphitic phase with amorphous area (

X

a

) domination. Scanning Electron Microscopy (SEM) images showed a honeycomb-like morphology, while Energy Dispersive x-ray (EDX) analysis indicated a carbon content of over 90%. Brunauer–Emmett–Teller (BET) analysis shows the high specific surface area of each sample (>1000 m2/g). The highest Pb(II) adsorption efficiency was achieved at 99.77%, with maximum performance at pH = 7.31, and temperature ∼26.7 °C, supported by the narrowing phonon vibration (

Δ

LO
−
TO

, lower electron loss function (ELF) shifts in wavenumber, higher

X

a

, and confirmed through adsorption kinetic and isotherm study. Here, we demonstrate a fresh methodology based on real-time monitoring using the Internet of Things of RAC as a promising adsorbent for Pb(II) removal with an adsorption capacity of 2.598 mg g−1. In addition, the ability of adsorption results without stirring aids to determine their ability when applied to the environment has been studied.
Producing Type Ia Supernovae from Hybrid CONe White Dwarfs with Main-sequence Binary Companions at Low Metallicity of Z = 0.0001
Authors: Guo Boyang , Meng Xiangcun , Tian Zhijia , Luo Jingxiao , Liu Zhengwei
Published: December 2024

The nature of progenitors of Type Ia supernovae (SNe Ia) and their explosion mechanism remains unclear. It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon–oxygen–neon white dwarfs (CONe WDs) when they grow in mass to approach the Chandrasekhar mass limit by accreting matter from a binary main-sequence (MS) companion. In this work, we combine the results of detailed binary evolution calculations with population synthesis models to investigate the rates and delay times of SNe Ia in the CONe WD + MS channel at a low metallicity environment of Z = 0.0001. For a constant star formation rate of 5 M
⊙ yr−1, our calculations predict that the SN Ia rates in the CONe WD + MS channel at low metallicity of Z = 0.0001 is about 0.11−3.89 × 10−4 yr−1. In addition, delay times in this channel cover a wide range of 0.05−2.5 Gyr. We further compare our results to those given by a previous study for the CONe WD + MS channel with a higher metallicity of Z = 0.02 to explore the influence of metallicity on the results. We find that these two metallicity environments give a slight difference in rates and delay times of SNe Ia from the CONe WD + MS channel, although SNe Ia produced at a low metallicity environment of Z = 0.0001 have relatively longer delay times.
The application of the finite elements method in the step wise transient method
Authors: Malinarič S
Published: December 2024

The evaluation of the Step-wise transient (SWT) method is verified by experiment simulation using Finite elements method (FEM) and true values of the specimen thermophysical parameters, which resulted in an input response. This is evaluated by fitting the analytical temperature function providing the initial guesses of the specimen parameter values. The accuracy of the results is increased by modifying the original analytical temperature function with another FEM calculation using these initial guesses. The computed temperature response in an numerical form is transformed into an analytical one, which can be used in fitting the input response. The obtained results are compared with true values and initial guesses. This procedure is conducted with specimens made from silicate glass and polymethylmethacrylate (PMMA).
Examining capture velocity in local exhaust ventilation utilizing a purpose-built workstation
Authors: Szekeres S
Published: December 2024

HVAC systems play a pivotal role in determining the overall energy consumption of industrial production halls and workshops, thereby emphasizing the necessity to optimize ventilation levels. Consequently, there is a paramount need to devise systems that strike a balance between energy efficiency and functional efficacy. This article elucidates a comprehensive investigation into the capture velocity of local exhaust ventilation (LEV) through the utilization of a purpose-built workstation within a controlled laboratory environment. The workstation, characterized by a 900 mm width and 450 mm depth worktop, was strategically outfitted with an exhaust duct proximal to the pollutant source, aligning with the operational objectives of the LEV system. The worktop was partitioned into square sections to facilitate precise documentation and subsequent reevaluation. Controlled fresh airflow was supplied through a duct positioned above the worktop. The study primarily centered on evaluating air velocity and turbulence intensity. Diverse configurations were experimented with at specified measurement nodes, and to avoid air extraction from behind the exhaust duct, a back sheet panel was installed. The results unequivocally demonstrated that the incorporation of a back sheet augmented capture velocities, underscoring its efficacy in enhancing LEV performance. These findings significantly contribute to advancing our comprehension of LEV efficiency and underscore the imperative of thoughtful design considerations and operational adjustments to ensure effective containment of contaminants within the operation environment.
Initial investigation of the relative humidity effect on the convective heat exchange using full-scale wind tunnel experiments
Authors: Kočí J , Navara T , Trush A , Pospíšil S
Published: December 2024

In this paper, an initial investigation of the effect of relative humidity on the rate of convective heat exchange is carried out. For this reason, a specific sample design was developed that was tested in the unique closed-circuit wind tunnel laboratory that allows for investigation of various environmental loads on full-scale samples. The analysis of experimental data indicated the relative humidity as a potential key factor with a sufficient level of significancy that may seriously affect the rate of convective heat exchange between sample surface and ambient air.
Evaluation of radionucłides transport parameters based on time dependent concentration profiles
Authors: Koci V , Kucerakova M , Zelenka J , Drab M , Vratislav S , Kalvoda L , Medved I
Published: December 2024

Alkali-activated aluminosilicate samples were prepared to be for testing and determination of radionuclides transport parameters. A solution of GdNO3 was put in contact with a face side of a prismatic specimen (lateral sides were sealed to make sure one-dimensional transport mode prevails) and the solution concentration in space and time were monitored and recorded using neutron radiography. The concentration profiles in different times were then processed (Stefan-Bolzmann transformation) and evaluated to obtain the diffusion coefficients. Within the evaluation, theoretical binding isotherms of Gd were used which corresponded to various levels of concentration. In this way, a sensitivity analysis was performed to investigate and quantify the impact of an isotherm variation on the diffusion coefficients values obtained. It has been found, a 10% variation in the binding isotherm values led to a difference in diffusion coefficient of up 30%. Beside concentration profiles measurement, an increased attention should be also paid also to a precise determination of binding isotherms.
Hygienic investigation of the evaporative cooling system installed in air handling units
Authors: Kostyák A , Kostyák F , Bodnár I
Published: December 2024

A significant portion of the total summer energy consumption of buildings is allocated to the treatment of ventilation air and cooling of spaces. One possible approach to reduce mechanical cooling energy consumption is indirect evaporative cooling. By implementing this method, the mechanical cooling energy demand of air handling units can be significantly reduced. Numerous studies and literature focus on the energy analysis of direct and indirect evaporative cooling system solutions. However, the hygiene assessment of these processes has received less attention thus far. This article presents an examination of the hygiene of evaporative cooling panels and the water used in these systems. The aim of the study is to assess the level of hygiene risk and explore potential cleaning technologies. It was shown that the applied disinfection method in this cooling system, using chemical solution flushing (in the case of 3 w/w% hydrogen peroxide solution) has proven more effective than chemical surface spraying process.
The evaluation of building materials moisture using the Analysis of Covariance
Authors: Jastrzębska M , Futa A
Published: December 2024

The paper presents the evaluation of some building materials moisture using the Analysis of Covariance (ANCOVA). The readouts present the dependence between the moisture of material, evaluated gravimetrically and permittivity values determined by TDR technique. Thanks to the ANCOVA method, it is possible to determine the moisture content in the particular materials regardless of the sensor construction and type of material. Additionally, in order to compare, the data obtained in the research also were analyzed using the traditional linear regression models.
The impact of changes in the physical properties of building material surfaces on heat transfer via electromagnetic radiation
Authors: Urzędowski A
Published: December 2024

The study aimed to determine the contact resistance at the interface of material layers within building partitions by conducting thermal and geometric analyses, both of which influence heat flow. Authors specifically tested the effects of changes in surface emissivity and surface roughness on heat transfer via electromagnetic radiation between parallel surfaces of building materials. To achieve accurate modeling, reverse engineering tools, including an optical 3D scanner and CAD software, were utilized to create detailed three-dimensional representations of the wall system, capturing precise geometrical features. The analysis of surface roughness provided insights into the microstructural changes before and after applying a reflection-smoothing coating, which significantly reduced surface emissivity from 0.93 to 0.29. Heat transfer simulations were carried out using computational fluid dynamics (CFD) software, applying the finite volume method to account for variations in surface roughness, air gap thickness, and concrete types. Authors sought to explorate how changes in surface roughness influence heat transfer via electromagnetic radiation and, as a result, affect the thermal insulation of walls.
Enhancing Production and Logistics Efficiency Through Dynamic Simulation: A Case Study in Transport System Optimization
Authors: Holubek R , Matúšová M
Published: December 2024

Dynamic computer simulation verifies before implementation how the production and logistics process system will work after implementation It is equally important in process automation when bottlenecks in processes are found and need to be optimised. Simulation can be used to verify the outcome of changes in production, logistics, warehouse or management processes before they are implemented in the real system. In the digital environment, experiments are conducted with internally deployed systems or processes, for example, the impact of process sequencing, orders, random occurrence of equipment failures, their retyping, the impact of logistics on production performance, and others. The customer thus avoids potential high financial and capacity losses resulting from additional modifications to the real system and gains certainty in decision-making in the planning phase. The aim of this paper is to provide a detailed analysis of the transport system in industry and to develop a simulation case study of a transport system. The simulation will be used to verify the proposed innovations in the case study.
The volume of stones stack calculated by different methods -a case study
Authors: Paszek J
Published: December 2024

Paper presents methods for calculating the volume of a stones stack located on an area of mining plant in southern Poland, used by modern engineering programs (the C-Geo program, the WinKalk program, the Geolisp program). The volume of the solid was calculated with the relative error in relation to the initial volume obtained in the Geolisp program (97 064.91 m3) and amounted to 97 207.22 m3 + 0.15% (the C-Geo program) and 97 001.00 m3 – 0.07% (the WinKalk program). The WinKalk program allowed for volume calculation with less than twice the relative error compared to the C-Geo program, however, both programs meet the accuracy requirements specified in the polish law.
Analysis of the load structure in the processing of aluminum alloys for automotive rims
Authors: Sapta D , Socalici A , Birtok Baneasa C , Putan V
Published: December 2024

The most commonly used aluminum alloys for manufacturing rims are the deformable alloys 6082 and 6061, as well as the casting alloy AlSi11. The increasing demand for such materials has led to intensified research and development activities in the field of high-strength and high-ductility aluminum alloys. Aluminum alloy rims must meet certain critical safety requirements and adhere to high standards of design, technical conditions, and processing. This paper presents the research conducted and the results obtained regarding the load structure in the processing of 6082 aluminum alloys intended for rim manufacturing. The load consists of aluminum waste and primary aluminum in various proportions depending on the alloying elements added to the metal bath of the waste used in the recipes.
Design and development of vaginal wall mimicking poly(ϵ-caprolactone) based nanofibrous prosthetic mesh for pelvic organ prolapse: evaluation of biocompatibility and antibacterial ability
Authors: Arul Murugan Preethi , Bellare Jayesh
Published: December 2024

Mechanical non-conformance of conventionally used transvaginal non-degradable meshes has led to complications such as organ perforation, dyspareunia caused by mesh stiffness and stress shielding. In this study, we have solved the dire need to mimic the mechanical properties of the vaginal wall by designing and developing a soft and elastic mesh made of polycaprolactone (PCL), citric acid modified polyethylene glycol (PEGC) and zinc oxide (ZnO) prepared through electrospinning and tested in vitro and in vivo. The mesh containing 90:10:0.1 of PCL, PEGC and ZnO (PEGC-15 0.1ZnO mesh) conforms to the mechanical properties of the vaginal wall of the pelvic floor, has a burst strength of ∼35 N even after gamma-sterilization and 28 d of degradation in in vitro. In vitro studies using adipose-derived stem cells revealed that the PCL-PEGC-15 0.1ZnO meshes were biocompatible and supported higher collagen production than commercial mesh. An in vitro bacterial adhesion study showed a 2-log reduction compared to commercially available mesh for prolapse treatment. Initial biocompatibility assessment in a rabbit model also showed that the PCL-PEGC-15 0.1ZnO mesh is biocompatible and supports fibrosis throughout the mesh. The softness and flexibility of the PCL-PEGC-15 0.1ZnO mesh based on in vitro trials and initial in vivo trials show that the mesh has a potential clinical impact for pelvic floor repair treatment.
Productivity of coniferous forests evaluated by remote sensing and field-based models
Authors: Kusbach jun A , Krejza J , Homolová L , Fischer M , Janoutová R , Horáček P
Published: December 2024

The inadequacy of Norway spruce (NS) monocultures in fulfilling ecosystem services, due to deteriorating health and consequent forest ecosystem collapses, has recently become a concerning issue for the forestry sector in Central Europe. This study investigates spruce forest productivity using in-situ field observations (DendroNetwork) and satellite remote sensing (RS) data in the Czech Republic during the past two decades. Tree growth index and moderate resolution imaging spectroradiometer net primary productivity were used to assess productivity at the national scale along an elevation gradient. The analyses of spatiotemporal variation in carbon dynamics indicate a decreasing trend in productivity in 51% and 80% (2800 km2 and 4200 km2) of the spruce stands from the RS and in-situ data, respectively. The increasing trend is particularly evident in montane regions, where satellite data identified an elevation threshold around 900 m a.s.l. while in-situ data 700 m a.s.l. In these energy-limited montane areas, NS may benefit from increased temperatures and may remain relatively safe from drought stress. The decreasing trends detected by both approaches indicate deteriorating conditions for NS in lower elevations. This study suggests that combining in-situ and RS data provides an efficient and robust way to estimate forest productivity at the national scale. The anticipated response of spruce forests associated with declines in productivity and growth in areas with low to moderate elevation points to the adverse effects of climate change by shifting the ecological optimum to higher elevations. We conclude that detailed mapping of forest response to changing environmental conditions is critical to support sustainable forest management and decision-making, ultimately reflecting the need to adopt adequate strategies to mitigate the impacts of climate change and related natural and anthropogenic disturbances.
An evaluation approach to PM2.5 policy effectiveness over South Korea based on a newly proposed scalable spatial decomposition method
Authors: Seo Jihoon , Lee Ahreum , Park Doo-Sun R , Youn Daeok , Kim Kyung Hwan , Park Chang-Eui , Kim Jin Young
Published: December 2024

Air quality management policies often exhibit spatial inconsistencies in effectiveness due to the diverse spatial scales of air pollution variability, which result from source characteristics as well as geographical and meteorological factors. To address this, the present study proposes a scalable spatial decomposition method to separate spatiotemporal air pollution data into background (nationwide), intercity-scale (tens of kilometers), and neighborhood-scale (several kilometers) components. This decomposition was achieved by introducing spatially varying effective ranges for intercity-scale variability at each station, based on the correlation coefficient distance of the background-removed component. Applying this approach to hourly fine particulate matter (PM2.5) concentrations from 535 monitoring stations across South Korea for 2021–2022, we evaluated the effectiveness of PM2.5 management policies. During the polluted cold season (December to March), the intercity-scale component contributed an average of approximately 18% of the total PM2.5 concentration in the Seoul Metropolitan Area (SMA) and Central Area (CA), which are densely populated and industrialized regions. In contrast, this component helped reduce PM2.5 levels in southeastern coastal areas, where high winds facilitate dispersion. The neighborhood-scale component contributed positively to PM2.5 levels near industrial complexes and ports but negatively in residential and commercial areas. The results demonstrate the effectiveness of central government-led intercity-scale regulations on total emissions allowances in the SMA and CA and highlight the need for additional local management targeting individual point sources near industrial complexes and ports. This study provides intuitive spatial decomposition tools for understanding PM2.5 pollution across spatial scales and offers policymakers a foundation for developing multi-scale mitigation strategies.
Reduction of unitary operators, quantum graphs and quantum channels
Authors: Salcedo L L
Published: December 2024

Given a unitary operator in a finite dimensional complex vector space, its unitary reduction to a subspace is defined. The application to quantum graphs is discussed. It is shown how the reduction allows to generate the scattering matrices of new quantum graphs from assembling of simpler graphs. The reduction of quantum channels is also defined. The implementation of the quantum gates corresponding to the reduced unitary operator is investigated, although no explicit construction is presented. The situation is different for the reduction of quantum channels for which explicit implementations are given.
Analysis of digitalization modern global trends and factors in the context of Ukraine’s agricultural sector
Authors: Kushnir N , Tsaruk D , Shpak V , Dobrovolskyi A , Didukh R
Published: December 2024

The article outlines trends, barriers and opportunities for digitalization in Ukraine’s agricultural sector. Due to the rapid information technologies development, digitalization has become a key economic growth factor, particularly in Ukraine’s agricultural sector, which is critical for food security, especially during wartime. The article examines the Ukrainian national economy digitalization level and the ICT impact through the Network Readiness Index, which measures a country’s institutional system digital transformation readiness. The 2023 NRI score indicates that, despite being a lower-middle-income country, Ukraine outperforms many states in education, ICT service exports, and government online services, demonstrating its potential for further growth. The study also assesses the artificial intelligence, the IoT and PETs impact on agricultural value chains, which contribute to improving the agricultural management efficiency, optimizing resource use, reducing costs and enhancing products competitiveness. It was found that one of the main digitalization barriers in Ukraine’s agriculture is the innovation financing insufficient level. Moreover, in 2024, the commercial loans cost for agriculture is among the highest across economic sectors. To address these issues, it is suggested to focuse on improving digital literacy, developing partnerships, enhancing the regulatory framework, implementing remote sensing technologies, attracting digital transformation investments through grants and green financing programs.
Consideration of risks in assessing the potential of drained lands: national and international aspects
Authors: Krasovska Y , Lesniak O , Podlevska O , Podlevskyi A , Kostrychenko V
Published: December 2024

Achieving sustainable development in Ukraine requires coordinating economic growth and environmental protection strategies. At the same time, ensuring the country’s food security is impossible without developing the water and land reclamation complex, which does not consistently achieve the goal of preserving and restoring the potential of land resources. Therefore, the issues of forecasting, preventing, and minimizing economic and environmental losses are of particular importance for the development of Ukraine’s economy and its sectors. This emphasizes the need to study economic and environmental risks in land use and develop strategies to reduce their negative impact on economic activity. Such research is also of great environmental importance, contributing to optimizing the use of natural resources, reducing the anthropogenic load on ecosystems, increasing their resilience and improving their condition.
Using correlation and regression analysis methods to assess the effectiveness of environmental projects
Authors: Kovshun N , Solodkyy V , Nalyvaiko N , Zhemba A , Syrotynska A
Published: December 2024

The article uses the methods of correlation and regression analysis to determine the feasibility of environmental projects. The dynamics of the main indicators characterizing the state of the environment of Ukraine is studied. Their dynamic forecasting is carried out. It was found that all the studied indicators are best described by a polynomial trend model of the 3rd degree. The hypothesis of a close causal relationship between the amount of environmental investment and the state of environmental pollution is put forward. A multi-factor regression model of the impact on pollutant emissions of capital investments and current expenditures on major environmental protection measures, capital investments in integrated technologies and clean-up was calculated using the STATISTICA package developed by StatSoft. The closeness of the relationship and statistical significance of the results obtained were analyzed. The main indicators that need to be included in the system of indicators for assessing the effectiveness of environmental investment are allocated.
Management and controlling of processes in the field of energy saving on the basis of Industry 4.0
Authors: Kuzmynchuk Nataliia , Fedorenko Irina , Kutsenko Tetiana , Aloshyn Serhii
Published: December 2024

Improving the energy saving system requires implementing particular management style based on controlling tools aimed at developing energy-efficient solutions and taking reasonable decisions that will ensure competitiveness of industrial enterprises. The aim of this study is to provide a two-component assessment of the level at which industrial enterprises are ready to implement innovative technologies in the field of energy saving in the context of Industry 4.0 using analytical and instrumental support of the management and controlling system. Analyzing the impact of innovation potential of industrial enterprises grouped by the values of innovation potential indicators on the level of their competitiveness has been carried out within the groups taken. The impact of innovation potential components on competitiveness level has been determined only for industrial enterprises of the third group. The defined correlation-regression model for industrial enterprises of the third group contributes to determining the influence of innovation potential components on the level of competitiveness. It has been proven that application of this approach makes it possible to solve a critical task of accelerating the development of Industry 4.0 technologies towards energy saving automation and digitalization, in particular, it has significantly increased the interest of industrial enterprises in transformational changes. It has also been substantiated that improving the energy saving system at industrial enterprises with the use of controlling tools allows for creative transition to Industry 4.0, which determines the current development trend of automating the energy resource management and digitizing the production processes.
Green Building Implementation in Campus Settings
Authors: Herzanita Ayu , Trisno Lestari Rini , Prautama Dewi Atri , Airunnisa Virginia Nur , Fairuz Insyirah Amirah
Published: December 2024

Many universities have declared themselves as green campuses to integrate sustainable development into education. One effort to implement a green campus is by improving infrastructure to be more environmentally friendly through the construction of green building. This study aims to identify the green building elements that have been implemented at the Faculty of Engineering Building at Pancasila University (FTUP). The green building elements that will be identified are appropriate site development, energy efficiency and conservation, water conservation, material resources and cycle, indoor health and comfort, and building environment management. Data collection methods are carried out by observation, interviews and archive analysis. Data analysis is conducted descriptively. The results of the study indicate that the elements that have been applied include appropriate site development, energy efficiency and conservation, material resources and cycle, and indoor health and comfort. There needs to be an increase in the implementation of green buildings so that the target of a green campus will be achieved.
Features of Reflectance Spectroscopy and Geochemistry Towards REE Mineralization in Weathered Granitic Clays
Authors: Nugraha A A S , Syafrizal  , Hede A N H
Published: December 2024

The rising global demand for rare earth elements (REEs) has intensified exploration efforts, particularly in regions like Indonesia with significant REE potential. This study explores the use of reflectance spectroscopy for rapid identification of REE-bearing clay minerals derived from weathered granite in West Kalimantan. Clay samples from distinct weathering horizons were analyzed using X-ray diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS), and reflectance spectroscopy. XRD confirmed the presence of kaolinite, dickite, gibbsite, and quartz, indicating their formation as weathering products of the host granite. While ICP-MS revealed that REE concentrations in the clay samples were lower than in the host rock, this observation suggests that the REE enrichment process within the clay minerals may still be ongoing or influenced by specific local geochemical conditions. Reflectance spectroscopy identified key clay minerals based on their characteristic absorption features in the shortwave infrared (SWIR) region. However, direct detection of REE-related absorption features was challenging due to the likely low concentrations and potential masking by iron oxides. This study highlights the potential of reflectance spectroscopy as a valuable tool for initial screening and identification of clay minerals in REE exploration, particularly when combined with other analytical techniques. Further research focusing on enhancing spectral analysis methods and targeting areas with potentially higher REE concentrations will be crucial in maximizing the effectiveness of this technique for REE resource discovery.
Application of Source Independent Full Waveform Inversion to Land Seismic Data: A Case Study of Donggi Field, Indonesia
Authors: Winardhi Sonny , Saputra Sigalingging Asido , Dinanto Ekkal
Published: December 2024

Full-waveform inversion (FWI) is a data-fitting process based on seismic full-wavefield modeling that provides high-resolution images of subsurface geological structures from observed field data. However, its applicability to real-world scenarios, particularly in land data, is limited due to several factors. These factors include the lack of modeling of strong surface waves, converted waves, phase dispersion, near-surface weathering layer distortion, and wave phenomena such as attenuation energy and distortion because of complex geology. Additionally, the source wavelet information is often missing for land surveys, and recorded waveforms can vary significantly due to spatially variant shot characteristics such as source charge size, shot depth, and hole pattern, as well as the distortion caused by the near-surface weathering layer. In this study, we address the main challenges of seismic data with a low signal-to-noise ratio and an unknown correct source wavelet. To solve for the unknown source wavelet, we use a source-independent objective function and perform several preprocessing techniques on the seismic input to improve the signal-to-noise ratio without significantly changing the amplitude. We use velocity analysis data as a prior model to reduce the non-linear problem. We demonstrate the effectiveness of our technique by applying it to land seismic data from the Donggi Basin in Indonesia, and our results show that the velocity model improves and has a better correlation with well-log data.
Evaluation of Depth Dependent Seismic Anisotropy within Limited Offset on Vertical Transverse Isotropy Media: Deep Water Reservoir Case Study
Authors: Oktariena Madaniya , Triyoso W , Fatkhan  , Sukmono S , Septama E , Wardaya P D , Murdianto B S
Published: December 2024

Hydrocarbon bearing sediment in deep water reservoirs are uniquely characterized by the body of water being an additional weight on the top of vertical sedimentary layering. While large aerial extent of deep water reservoirs is known for their ability to contain substantial amount of reserves, they come with technical difficulties mainly in acquisition and imaging aspect. Deep water seismic imaging more often than not suffers from the hockey stick effect found in the long offset. At the same time, the presence of hockey stick in seismic long offset could be utilized as a tool to extract anisotropy information from seismic data. However, the deep target level requires a rather long offset in seismic data to be able in capturing a proper hockey stick condition. This research intends to evaluate seismic anisotropy behaviour in various depth level within a limited offset range instead of the commonly used very long offset. Seismic related anisotropy (η) is extracted from travel time error as a delta to the isotropic travel time. The extracted anisotropy η is to be plotted against several known VTI travel time approximation in order to identified the equation that most fitted to the deep water real data condition. Several depth levels are to be analysed as an attempt to capture depth related variation in multi reservoir scenarios. Observation is conducted on PMBG Seismic Gather around several well location as point of validation. The result shows indication of seismic anisotropy degree variation within progressed depth that could be concluded as depth dependant behaviour. The fact that the observed area has a typical character of weak anisotropy which only has a small impact on seismic data encourages a possibility to delineate anisotropy from seismic data with a certain treatment. Analysis on limited range offset seismic promotes the utilization of old vintage seismic data for seismic anisotropy extraction that contribute to the vision of using a new insight on the existing data as part of enhanced oil recovery strategies.
A High Resolution of Terrain Gravity of Bandung Area
Authors: Gunawan I , Prasetyo N , Alawiyah S
Published: December 2024

The Bandung basin spans around 30 km by 60 km and is encircled by mountains. Therefore, the gravity due to terrain variations has significantly contributed to the area’s Complete Bouguer Anomaly (CBA). In this study, we have applied a high resolution of terrain gravity (TG) using the block of rectangular prisms with 100 m x 100 m x 10 m dimensions. The investigation includes up to 70 km x 100 km terrain areas where the data was obtained from the shuttle radar topography mission digital elevation model (SRTM DEM). The results show that the southern region has about 20 mGal TG higher than the northern region due to more and higher mountain variation. Our investigation also found that the reasonable terrain areas included in the calculation must be at least 40 km wider from the outer gravity stations to get less than one mGal change in the 5 km terrain area width change. This result gives a good overview of the terrain effect on gravity calculation and interpretation, especially in the Bandung area.