bluuebunny/crossref_metadata_2025_split huggingface dataset:
Computation of the Damping Loss Factor of Heterogeneous Meta-structure using the Wave Finite Element-based Methodology
Authors: Cui Dongze , Ichchou Mohamed , Atalla Noureddine , Zine Abdel-Malek 
Published: December 2024

Abstract
Existing methodologies employed for the computation of vibroacoustic indicators of heterogeneous structures with high contrasting properties have limitations in terms of precision and computational speed. The present study, focuses on estimating the composite Damping Loss Factor (DLF) of these structures. It presents a Wave Finite Element-based methodology that uses the forced response of a Unit Cell (UC) representative of the periodic meta-structure to calculate the DLF through a power balance. Various configurations, ranging from a simple plate to complex laminated configurations, are presented to highlight the advantages and limitations of the presented methodology.
On the Significance of Parameter Uncertainties for Prediction of Leak Noise Wave Speed in Buried Pipes
Authors: Scussel O. , Muggleton J M , Karimi M , Williams P , Kalkowski M K , Joseph P F , White P. 
Published: December 2024

Abstract
The modern world is facing the challenging issue of water wastage due to leaks, which is causing severe economic, environmental and social impacts. Consequently, the inspection and maintenance of buried water pipes is crucial and there is still a lack of investigations towards the uncertain parameters affecting the wave speed associated with the predominantly fluid-borne wave s=1, the main carrier of leak noise. This study investigates the effects of uncertainties present in the pipe and soil parameters which are affecting the speed of propagation of the leak noise wave. To achieve this, a sensitivity analysis is performed using Monte Carlo simulations and Sobol’ indices. Uncertainties are commonly associated with the material and geometrical properties of the pipe along with the surrounding soil characteristics. However, the significance of these parameters varies depending on the type of soil in which the water pipe is buried. In clay soil, the soil-related parameter plays a crucial role compared to sandy soil and this is verified through some experimental work carried out in two water pipe systems with very different properties, one in the UK and the other one in Brazil. This research is of fundamental importance for determining the most critical parameters affecting the leak noise wave, allowing to evaluate and integrate uncertainty information into decision-making of current technologies, such as loggers and leak noise correlators, aiming enhanced detection and location of water leakage in buried plastic water pipes.
Estimation of loosening torque in bolted joints from experimental data and regression models
Authors: Coelho Jefferson , Machado Marcela , Dutkiewicz Maciej 
Published: December 2024

Abstract
Structures are often joined using fasteners such as rivets or bolts, which are chosen based on their ability to meet performance requirements. Bolts are popular due to their advantages, such as avoiding movement and ensuring the stability and security of bolted joints. However, one of the main issues with fasteners is loosening, which can be caused by shock and vibration and lead to serious damage and structural failure. The use of machine learning techniques for bolt joint verification is limited. Hence, this study proposes a machine learning workflow centred on estimating torque by analysing raw spectral signals derived from experimental tests. This approach accounts for intrinsic variabilities in torque estimation and enhances our results performance. To enrich the experimental dataset, the study employs a technique involving the generation of synthetic datasets based on statistical moments derived from experimental data. Results show that machine learning can estimate torque in joint structures based on data collected under various conditions, improving performance with the lowest error rate.
Nonlinear performance enhancement of imperfect ring-based Coriolis Vibratory Gyroscopes
Authors: Arifin D. , McWilliam S. 
Published: December 2024

Abstract
The rate sensing performance of ring-based capacitive Coriolis Vibratory Gyroscopes (CVGs) is susceptible to the effects of imperfections and electrostatic nonlinearities. This research investigates the use of the nonlinear electrostatic forces to nullify these effects and replicate linear and trimmed sensor performance at increased vibration amplitudes. The approach used involves applying a suitable voltage distribution to modify the mechanical sensing mode, and a mathematical model is used to demonstrate the implementation of this scheme. For the case of 8 evenly distributed electrodes, a balancing voltage component is introduced to counteract the net forces stemming from the imperfection-induced quadrature coupling and the nonlinear frequency imbalance. The effects of the implementation are demonstrated in terms of improvements to rate sensitivity, bias rate and quadrature error of the device mechanical output. Finite element results are also included to validate the potential of this force balancing scheme. It is shown that the proposed scheme enhances device performance by reducing the bias rate and mechanical quadrature response to negligible levels and increasing rate sensitivity at increased drive amplitudes.
A numerical study on the interaction between friction and vibration in a friction-involved dynamical system
Authors: Algara Ahmad , Yuan Jie 
Published: December 2024

Abstract
Friction can be regarded as a dynamic variable within a dynamical system including sliding interfaces. In general, friction and vibration effects have been studied together in many studies but usually studied in one direction, primarily focusing on the effects of friction on vibration and other direction has not been widely studied, with limited attention given to their closed-loop feedback interactions in engineering applications. The presence of friction and contact surfaces introduces nonlinearity, affecting the system’s dynamic response. Moreover, oscillations applied to these structures can influence contact mechanics at friction interfaces, particularly relevant for decommissioning large-scale structures like wind turbines. However, modelling the intricate interplay between friction and vibrations is overly complex, requiring expertise from fields such as contact mechanics, tribology, and nonlinear dynamics.
The objective of the study is to investigate the mutual influences between structural vibrations and contact friction for friction-involved dynamical systems. A two-degree-of-freedom (2-DoF) lumped-parameter model has been developed to a represent friction-involved vibration system. This model incorporates the representation of contact friction using a Jenkins element, accounting for stick, slip, and separation motions occurring at the friction interface. The steady-state response of the system is calculated using the Harmonic Balance method with an alternative frequency-time scheme where its results are validated using a time domain solver. A parametric study is then conducted to examine the mutual relationship between the frictional and vibrational behaviour such as excitation level, contact stiffness, normal load, coefficient of friction, dynamic response, and the effects of vibration on friction force through a newly introduced quantity called equivalent stiffness.
A beam with an attached damping layer with an acoustic black hole profile
Authors: Wan Zhiwei , Zhu Xiang , Li Tianyun , Liu Xinru 
Published: December 2024

Abstract
An acoustic black hole (ABH) structure whose thickness varies according to a power law has received extensive attention in vibration reduction. However, ABH cannot be used as the primary bearing component in engineering, as the thickness reduction of ABH itself reduces its stiffness. In this article, the vibration characteristic of a beam with an acoustic black hole damping layer is studied and compared with a damping layer with uniform thickness. The beam and damping layer are based on the Timoshenko beam theory, using virtual springs to connect each other. The correctness of the proposed method is verified through the finite element method. The case studies show the proposed composite beam structure has lighter mass and lower vibration levels, compared with the beam attached with uniform damping layer.
Designing stacked multi-wedge acoustic black holes using parameter variations
Authors: Käfer Max , Dohnal Fadi 
Published: December 2024

Abstract
Progressive industrialization is causing noise and vibration levels to rise. The negative impact on humans and the environment calls for protective measures to mitigate the disturbing sound and vibrations. Recent developments of noise absorbing materials have included acoustic metamaterials and acoustic black holes (ABH) into the focus of attention. It was shown analytically that no sound energy can escape from the ABH if the thickness of a tapered end goes to zero and the ABH is infinitely long. The wedge-shaped ABH serves here as a basis for further research and studies on matching focusing on specific frequency ranges. The combination of the CAD-software SOLIDWORKS, the FE-software COMSOL Multiphysics and Matlab enables a robust procedure to optimize the ABH design for specific, even low, frequency ranges. Therefore eigenfrequency, time domain and energy studies have been calculated. Combining the results is showing how the ABH performs at its eigenfrequencies. As a base structure, a simple beam was added to the ABH. If the beam stays at rest and the ABH is oscillating, its performance is positive meaning that the vibrational energy is concentrated at the tip of the ABH. The main focus here is the tuning of the ABH with parametric studies using parameter variations to the frequency range of interest. The resulting eigenfrequency curves are not only showing the optimal design parameters, but also the performance of the ABH at its frequency ranges. Furthermore a case study with a pipe system was carried out of an adapted ABH, underlining its performance.
Rectangular ring resonator-based symmetrically engineered metamaterial absorber for electromagnetic interference shielding in the S and C bands
Authors: Soliman M M , Chowdhury N M , Mansor M F , Misran N , Alam T , Baharuddin M H B , Islam M T 
Published: December 2024

Abstract
This research aims to investigate the use of metamaterial (MM) structures in S and C bands for efficient EMI shielding. The designed MM absorber consists of four rectangular ring resonators (RRR) made of copper separated by a 1.3 mm thick FR-4 dielectric layer with dimensions of 15 mm × 15 mm and a ground layer of annealed copper with a thickness of 0.035 mm. The simulated results demonstrate two absorption peaks at 4.1 GHz and 6.8 GHz, with absorption values of 99.9% and 96%, respectively. The properties of the reflection coefficient are investigated using a circuit model of the MM absorber, and the electromagnetic wave absorption mechanism is further studied by examining the surface current, H-field, and E-field distributions at absorption peaks. The metamaterial (MM) absorber exhibits almost perfect absorption across a significant angle of incidence and polarisation angle up to 60 degrees. The suggested MM design provides dual-band shielding characteristics with a -10 dB reflection coefficient (S11) at 4.0-4.14 GHz and 6.83-6.89 GHz. Furthermore, the Metamaterial (MM) absorber offers a shielding efficiency of > 20 dB in all bands, according to the theoretical analysis. The MM’s 99% absorption and shielding capability makes it suitable for a wide range of high-potential applications.
Design and Fabrication of High-Gain Dual Linearly Polarized Patch antenna at 28 GHz
Authors: Mohd Hamzah Siti Zainab , Abdul Malek Norun Farihah , Mohamad Sarah Yasmin , Mohd Isa Farah Nadia 
Published: December 2024

Abstract
Extensive research on millimeter-wave frequency bands is currently in rapid development throughout the world, specifically at an operating frequency of 28 GHz, and Malaysia is no exception. The most conventional patch antennas covered a limited polarization feature of single polarization of radiated beam signals. In order to meet the high demands of network users with a higher data rate, the radiated beam signal coverage should be as wide as possible to ensure the stability and consistency of the received signals for the users. This leads to the development of the dual polarization feature of single-layer antenna design. In this work, a dual element (70 x 70 mm2) patch antenna at 28 GHz has been designed using CST Studio Suite and fabricated using Rogers RT5880. The antenna has been oriented to the right (+45°) and to the left (-45°) from the normal plane to realize a dual linear polarization state. The simulation and measurement results show that the reflection coefficient obtained for all antennas is less than -10 dB. The simulated and measured radiation patterns of the antennas are also shown in this paper. It is observed that the proposed antenna achieves a dual-polarized state with a higher gain of 11.16 dBi, compared to 4.97 dBi for a single patch. This dual-polarized antenna can be applied in various applications, particularly for MIMO and 5G mobile communication networks.
Dielectric and microwave properties of latex rubber composites filled with various carbon-based fillers
Authors: Ayob Nur Syuhada , Yahaya Nor Zakiah , Aqiman Mohamad Zul , Ramli Ramzun Maizan , Sulaiman Shukri , Mahmud Mohd Nazri , Rahim Hasliza A 
Published: December 2024

Abstract
This study investigates the dielectric and microwave properties of latex rubber composites filled with various fillers, aiming to enhance their performance in applications such as electromagnetic interference (EMI) shielding, microwave absorption, and electronic devices. Composites were prepared by incorporating different types of fillers, including activated carbon-based rice husk (AC-RH), graphite (G), bamboo charcoal (BC), and calcium carbonate (CC). The dielectric properties were evaluated with a commercial coaxial probe (Agilent 85070E), and the microwave properties were determined with an insulated monopole sensor operating in the 2 to 20 GHz frequency range. The results showed that fillers significantly improved the dielectric and microwave properties of rubber composites, with AC-RH exhibiting the greatest improvement. AC-RH has the lowest reflection loss, -13 dB at 10 GHz.
Nutrient Content of Water at Different Landuse in Peatland in Central Kalimantan, Indonesia
Authors: Sulistiyanto Y , Jaya A , Zubaidah S , Sustiyah S , Jovani-Sancho J 
Published: December 2024

Abstract
Research on water in four different landuse in peat swamp area in Kalampangan Central Kalimantan, Indonesia was carried out and water was sampled every one month from May 2018 to April 2019 and analyzed for pH, soil electrical conductivity (EC) and total content of Ca and Mg. Aim of the research is to obtain the different in nutrient concentration in different land use. Methods, six permanent locations in each land use were used to gather water samples. The landuse were established in (a) Peat swamp forest (b) Jelutung forest (c) Agriculture area and (d) Oil Palm. Water samples were taken at 100 cm below the surface at each peatland site. Result show that water in Forest is very acid with average pH (4.24 ±0.48), Jelutung forest (4.68 ±0.33), Agriculture area (4.69 ±0.62), and Oil Palm 4.67 ±0.38). Soil Electrical Conductivity (EC) in Forest is the lowest with average 0.32 ±0.11 mS.cm -1, Jelutung forest (0.56 ±0.36), (c) Agriculture area (0.93 ±0.52), and (d) Oil Palm (0.52 ±0.19), Similary to Soil Electrical Conductivity (EC), Ca content in water in Forest is the lowest with average 8.20 ±4.54 mg.l-1, Jelutung forest (19.72 ±10.42), (c) Agriculture area (23.60 ±11.54), and (d) Oil Palm (17.45 ±8.27). Mg content in water in Forest is the lowest with average 0.51 ±0.40 mg.l- 1, Jelutung forest (0.93 ±0.47), (c) Agriculture area (2.77 ±1.57), and (d) Oil Palm 0.82 ±0.59). The highest nutrient cotents of Ca and Mg in water was Agriculture area and the lowest in Forest area. Furthermore, nutrient contents of water at each landuse during dry season was higher than wet.
CH4 Emissions on Smallholder Plantations in The Tropical Peatlands of Central Kalimantan, Indonesia
Authors: Sustiyah  , Dohong S , Ariani N P , Soemamo  , Jaya A , Sulistiyanto Y , Damanik Z , Umbing R A , Surawijaya P 
Published: December 2024

Abstract
The development of peatlands is considered a contributor to greenhouse gas (GHG) emissions originating from land clearing, burning, and land management. Greenhouse gas emissions are one of the factors causing climate change and global warming. One of the main greenhouse gas components of peatlands is methane. This study aims to determine the effect of conversion of peat land to smallholder plantations on the amount of CH4 emissions and the water table. This research was conducted in the smallholder farming at Kalampangan Village, Palangka Raya City, Central Kalimantan Province, Indonesia. The results showed that the conversion of peat land to smallholder plantations had an effect on CH4 emissions and the water table. CH4 emissions in oil palm plantations are higher and the water table is deeper than in dragon fruit plantations. CH4 emissions in oil palm plantations were 1.66-53.18 mg CH4 m−2 hours−1 and in dragon fruit orchards it ranged from 12.43-35.00 mg CH4 m−2hours−1. The water table values in oil palm plantations ranged from (-145.33- -196.67) cm and in peat land dragon fruit gardens ranged from 115.00-167.17 cm. CH4 emissions on peatlands before conversion were 0.42-3.92 mg m−2hours−1 and the water tabel value is (-69.48-+22.40) cm in rainy season conditions. This condition shows that the location of the smallerholder plantation land is in anaerobic conditions. The soil temperature in the chamber in the peatlands of oil palm plantations ranges between 27.20-38.60 °C, and in the peatlands of dragon fruit plantations ranges from 34.09-39.45°C. The soil temperature around the chamber in the peatlands of oil palm plantations ranges from 27.81-37.17 °C, and in the peatlands of dragon fruit plantations ranges from 32.51-38.59 °C.
Growth of 7 (Seven) Years Old Red Meranti (Shorea leprosula Miq.) in the Palangka Raya University Seedling Seed Orchard
Authors: Sudomo MFA , Pidjath C , Kalawa D A 
Published: December 2024

Abstract
This research aims to analyze the growth and identify peat soil chemical properties under the Shorea leprosula Miq.stand. This research was carried out at the Palangka Raya University Seedling Seed Orchard (SSO) which is located in the Green Campus Area of Palangka Raya University. The sampling method in the field uses a purposive sampling method to take the first tree sample on each route and continue with Systematic Sampling, by measuring 10 tree samples on each route, the total number of trees measured on all routes are 300 trees. Meanwhile, to identify soil by taking soil samples in 2 plots, For soil chemical characterization analysis. Based on research results S. leprosula growth annual increment in diameter, height, and volume were 0.99 cm. year-1 66.96 cm year-1 0.0023 m3. year-1 respectively. Soil fertility criteria under the Meranti Merah stand, it can be seen that the only P content is very high in the soil, while the soil pH has very strong acid and several other elements have low and shallow criteria levels.
Energy Intensity and Employment: evidence from Latin American countries
Authors: Vilema-Escudero Segundo F. , Ruiz-Martínez Miguel , Manya-Orellana Marlon , Arguello-Núñez León 
Published: December 2024

Abstract
This study investigates the relationship between energy intensity and employment in 13 Latin American countries, differentiating between countries with and without OECD relations. Using a panel data regression model from 2000 to 2017, the analysis reveals that energy intensity negatively impacts employment, particularly in OECD-related countries. The study also examines the moderating role of economic performance and foreign direct investment (FDI) in this relationship. While economic growth is associated with higher energy efficiency, it does not consistently mitigate the negative effects of energy intensity on employment. Similarly, FDI shows a limited impact in moderating the energy-employment relationship. These findings highlight the need for comprehensive policies that promote both energy efficiency and quality employment in diverse economic contexts. Future research should explore the influence of technological innovation and sector-specific factors on the energy-employment relationship in lower-income countries.
Farmers’ adaptation practices in climate-stressed coastal Bangladesh: a systematic review
Authors: Ashik Ur Rahman Md , Swarnokar Sadhon Chandra , Ahasan S M Nayem , Mohibbullah M , Mou Sadia Islam , Gain Animesh K 
Published: December 2024

Abstract
Climate change poses serious threats, making it crucial to develop strong adaptation strategies. This is especially true in Bangladesh, where agriculture, the backbone of the economy, is highly vulnerable. Local communities in Bangladesh have used Indigenous knowledge and practices to adapt, but there is a lack of systematic examination of these strategies. In this study, we review literature from Web of Science, ScienceDirect, Scopus, and Google Scholar using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We identify various adaptation strategies grouped into six main themes and twenty-six sub-themes: crop management, water management, farm management, financial management, social adaptation, and traditional/local knowledge use. Diversifying income sources stands out as a key strategy against climate challenges. However, most strategies are short-term, reactive, and lack long-term sustainability. Our study highlights the importance of local adaptation strategies and questions their integration into national and regional development plans. The dominance of foreign-funded projects in publishing research shows the vital role of international collaboration in improving research quality and global knowledge exchange. The findings are relevant for regions where coastal agriculture is vital but impacted by climate change, including countries in Asia-Pacific, Africa, and South America.
Cost-effective fabrication of NiCo-LDH

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Ni inverse opal-like electrodes for high current stable supercapacitors
Authors: Torres Soto Hiram Eli , Encinas Armando , de la Torre Medina Joaquín 
Published: December 2024

Abstract
This study presents a cost-effective fabrication process for synthesizing NiCo-layered double hydroxide (NiCo-LDH) active materials on Ni inverse opal (Ni-IO) porous networks anchored on bakelite PCB substrates without using binders. Electrodeposition at a constant reduction potential was used to grow NiCo-LDH coatings on Ni-IO current collectors to investigate the influence of their thickness on the electrochemical performance of NiCo-LDH

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Ni-IO electrodes at current densities as high as 184 A g−1. The highest specific capacitance values between 548 F g−1 and 588 F g−1 and excellent cycling stability after 5000 galvanostatic charge/discharge cycles at 150 A g−1, were achieved using a 67 nm thick LDH coating. Specifically, the capacitance retention of 92% and coulombic efficiency of 99% after the cycle life tests at high current densities validate the remarkable stability of the electrodes. Additionally, remarkable energy and power densities were recorded for electrodes with LDH thickness between 30 and 67 nm, ranging from 49 to 65.7 Wh kg−1 and 26.4 to 128 kW kg−1 at current densities between 17 and 184 A g−1. The superior cycling stability, high energy and power densities, and cost-effective production of NiCo-LDH

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Ni-IO electrodes on commercial PCB phenolic substrates highlight their potential for high-performance supercapacitor applications.