bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resilience and Loyalty in the Face of Adversity: A Case of Local Employees in Kerala’s Backwater Tourism
Authors: Ajoon E. Joshu , Hayes Stu 
Published: February 2024

Summary
This case study reports on Kerala’s backwater tourism and the associated experiences of houseboat employees in the sector. Kerala’s backwater tourism is a significant facet of the state’s tourism industry, drawing both foreign and domestic tourists. Houseboats, referred to as ‘kettuvallam,’ play a central role in backwater tourism, harmonizing tradition with modernity. Despite gaining global recognition, challenges such as escalating costs and external crises, including the COVID-19 pandemic, have impacted Kerala’s backwater tourism sector, leading to severe hardship and job insecurity among employees. Despite these adversities, interviews conducted as part of the case study reveal remarkable levels of ongoing resilience and loyalty on the part of houseboat employees, most of whom are local residents. Their resilience and loyalty are rooted in affective commitment and intrinsic motivation, wherein houseboat employees see themselves as custodians of tradition and ambassadors of the backwater region. In turn, their unwavering dedication may be seen as being a vital factor that can contribute to the ongoing adaptability and resilience of the backwater tourism sector as a whole.

Information
© The Authors 2024
Test mass charge estimation for the space inertial sensor with extended Kalman filter
Authors: Gu Weihong , Cheng Kai , Hong Wei , Zhang Jiawei , Song Wenrui , Mo Chong , Huang Jianping , Song Wenlong 
Published: February 2024

Abstract
Charge Management System (CMS), aimed at mitigating charge-induced noise on an isolated free-falling test mass (TM), is a crucial component of space inertial sensors in various spaceborne gravitational missions. The estimation of TM charge is one of the tasks of CMS, directly impacting CMS performance. However, current methods for TM charge estimation suffer from slow response and significant estimation errors. This paper presents a new charge estimation method that combines the force modulation principle with an extended Kalman filter (EKF). We analyzed the relationship between the TM surface potential and TM motion, then established a mathematical model. The estimation of TM charge is accomplished through the EKF algorithm. A charge estimation simulation model was developed in Simulink, and experiments were conducted to evaluate the performance of the charge estimation methods under varying charge conditions. The experimental results demonstrate that the EKF method obtains more accurate estimation results and faster convergence rates, compared with Kalman Filter (KF) and Quadrature demodulation (QD) methods. The KF and QD methods show larger errors when the estimated charge is greater than 106e order, meanwhile the QD method exhibits slower convergence rates. The presented method is expected to be beneficial for the CMS of on-orbit inertial sensors.
High-precision robotic kinematic parameter identification and positioning error compensation method for industrial robot
Authors: Jiang Guanchang , Ma Yinglun , Guo Zhibo , Li Ming , Chen Hongfang , Shi Zhaoyao 
Published: February 2024

Abstract
A method based on laser tracing multi-station measurement technology is proposed in this paper. The method identifies the robotic kinematic parameters and compensates for the absolute positioning errors of industrial robots to improve the absolute positioning accuracy further. The position coordinates of industrial robots are typically measured using laser tracking devices. In this study, the measurement accuracy of an industrial robot is further enhanced using laser tracer multi-station measurement technology. Additionally, the least absolute shrinkage and selection operator (LASSO) algorithm was used to identify the robotic kinematic parameters. Compared with the commonly used least squares algorithm, the LASSO algorithm improved the parameter identification accuracy and the compensation effect on absolute positioning errors. A position error model was established based on the parameters of the modified Denavit–Hartenberg model of an industrial robot. Using the LASSO algorithm, the robotic kinematic parameters were accurately identified, and the original data in the controller were replaced to compensate for the geometric errors of the industrial robot. In the compensation experiments, after implementing the geometric error compensation, the average absolute positioning error of the industrial robot decreased by 41.15%, demonstrating a significant improvement in the absolute positioning accuracy.
An iterative reconstruction algorithm for unsupervised PET image
Authors: Wang Siqi , Liu Bing , Xie Furan , Chai Li 
Published: February 2024

Abstract

Objective. In recent years, convolutional neural networks (CNNs) have shown great potential in positron emission tomography (PET) image reconstruction. However, most of them rely on many low-quality and high-quality reference PET image pairs for training, which are not always feasible in clinical practice. On the other hand, many works improve the quality of PET image reconstruction by adding explicit regularization or optimizing the network structure, which may lead to complex optimization problems. Approach. In this paper, we develop a novel iterative reconstruction algorithm by integrating the deep image prior (DIP) framework, which only needs the prior information (e.g. MRI) and sinogram data of patients. To be specific, we construct the objective function as a constrained optimization problem and utilize the existing PET image reconstruction packages to streamline calculations. Moreover, to further improve both the reconstruction quality and speed, we introduce the Nesterov’s acceleration part and the restart mechanism in each iteration. Main results. 2D experiments on PET data sets based on computer simulations and real patients demonstrate that our proposed algorithm can outperform existing MLEM-GF, KEM and DIPRecon methods. Significance. Unlike traditional CNN methods, the proposed algorithm does not rely on large data sets, but only leverages inter-patient information. Furthermore, we enhance reconstruction performance by optimizing the iterative algorithm. Notably, the proposed method does not require much modification of the basic algorithm, allowing for easy integration into standard implementations.
A harmonic method for measuring electron temperature and ion density using an asymmetric double probe
Authors: Eo Hyundong , Park Sung Joon , Kim Ju Ho , Chung Chin-Wook 
Published: February 2024

Abstract
The harmonic method using a symmetric double probe was developed for measuring electron temperature and ion density Oh et al (2012 Meas. Sci. Technol.
23 085001). When an alternating voltage is applied to the symmetric double probe where the two areas of the collector for current collection are equal, the fundamental frequency current and third harmonic currents are generated. The electron temperature and ion density are obtained by measuring the fundamental frequency current and the third harmonic current. However, it is observed that the third harmonic current can rapidly decrease to the level of base noise when the ratio of the applied voltage to the electron temperature decreases. Therefore, it is necessary to increase the harmonic currents generated to improve measurement accuracy for electron temperature and ion density. In this paper, a harmonic method using an asymmetric double probe with different collection areas is proposed to measure electron temperature and ion density. By using the double probe with different collector area, the fundamental frequency current and the second harmonic current are generated. In the proposed method, the electron temperature and ion density are obtained by measuring the fundamental frequency current and the second harmonic current. It is found that the accuracy of the electron temperature can be improved by measuring the second harmonic rather than measuring the third harmonic current. For quantitative comparison, the electron temperature and ion density obtained by the proposed method were compared with the electron temperature and electron density obtained by the measurement electron energy probability function, which showed good agreement between them in argon plasma at various conditions. In addition, it was experimentally verified that the electron temperature can be accurately measured even when the chamber is electrically insulated, and a dielectric layer is deposited on the collectors of the double probe, such as in the plasma process.
Design and experiment study of a novel dual-channel independent-coil magnetorheological grease damper
Authors: Wang Huixing , Li Dong , Xue Shuna , Sun Junjie , Wang Jiong 
Published: February 2024

Abstract
In order to address the issue of reduced damping force dynamic range in magnetorheological (MR) damper caused by the high zero-field viscosity of MR grease, known for its sedimentation stability, this paper introduces a novel dual-channel independent-coil MR damper (DCICMRD). Firstly, the dual-channel configuration and the magnetic circuit structure of independent coils were meticulously designed, and a genetic algorithm was employed to conduct multi-objective optimization of the structural parameters for DCICMRD. The optimization results indicate that all performance metrics of the damper post-optimization exhibit improvements exceeding 15%. Then, the theocratical model of the damping force for DCICMRD under three operational modes are established, and the output damping force of various input currents for different operating mode is obtained. Finally, the DCICMRD was manufactured and subjected to dynamic performance testing. The results revealed that the damping force dynamic range in Mode III, i.e. dual-channel structure, can achieve approximately 15 times, whereas Mode I, i.e. traditional single-channel structure, only attains approximately 9 times. The aforementioned research holds significant implications for expanding the further engineering applications of MR dampers.
Exploring chloride-induced corrosion in reinforced concrete structures through embedded piezo sensor technology: an experimental and numerical study
Authors: Morwal Tarun , Bansal Tushar , Azam Ammar , Talakokula Visalakshi , Jothi Saravanan T 
Published: February 2024

Abstract
Corrosion of steel in concrete is one of the major problems with respect to the durability of reinforced concrete (RC) structures. Thus, monitoring the corrosion in real-time is essential to prevent structural damage. However, one of the main challenges is to simulate the real-time development of corrosion in the RC structure. In recent years, smart aggregates, also called embedded piezo sensors (EPS), have become increasingly popular for monitoring localized and corrosion damage in RC structures using electro-mechanical impedance (EMI). This paper presents the experimental and numerical investigation of corrosion in RC structures subjected to the chloride-laden environment using EPS via the EMI technique. To fulfil this objective, the study has been carried out in two stages such as; in the first stage, the experiments are conducted on the RC specimen, and the EMI response was obtained both in a pristine state and when accelerated corrosion progressed. In the second step, a numerical model of the RC specimen has been developed based on the experimental data in the COMSOL software, and the effect of corrosion in the form of varying mass loss percentages has been simulated. Based on the results, it is concluded that the experimental and numerical conductance signatures before and after corrosion are matched. The deterioration in terms of stiffness loss in the RC specimen was 18.20% at 30% mass loss.
Mechanistic prediction of folding angles in 4D printed shape memory polymers under varied loading conditions
Authors: Li Ye , Ponnappan Harish Kumar 
Published: February 2024

Abstract
Four-dimensional printing technology empowers 3D-printed structures to change shapes upon external stimulation. However, most studies did not consider recovery under loaded conditions. This paper introduces a mechanistic prediction model for forecasting recovery angles in 4D printing utilizing shape memory polymer under various loads. The model integrates Neo–Hookean model to describe the non-linear stress–strain relationship with experimentally determined force density data to characterize polymer restoration properties under various loads. Validation was demonstrated by the recovery experiment of a 3D-printed polylactic acid-thermoplastic polyurethane composite structure loaded by means of a cord and pulley mechanism. The predictive outcomes exhibited reasonable agreement with experimental results, demonstrating a trend of more accurate forecasts as the applied load increased. The model can accommodate various active materials provided that the pertaining force density data is accessible. The predictive model supports the design, optimization and material selection for 4D-printed structures to meet specific performance requirements.
A multi-directional and multi-modal galloping piezoelectric energy harvester with tri-section beam
Authors: Xia Cuipeng , Yang Jian , Tang Lihua , Yin Peilun , Li Zifan , Wang Bin , Aw Kean C 
Published: February 2024

Abstract
A traditional wind energy harvester based on galloping can only harvest wind energy from one specific direction, which fails to work efficiently in a natural erratic environment. In this study, we propose a galloping-based piezoelectric energy harvester that can collect energy from wind flow in a wide range of incident directions with multiple vibrational modes being excited. The proposed harvester is composed of a tri-section beam with bonded piezoelectric transducers and a square bluff body with splitters. Finite element analysis of the tri-section beam structure is first performed and confirms the clustered natural frequencies that ease the excitation of different modes. Then, the aerodynamic characteristics of various bluff bodies is conducted through computational fluid dynamics to compare the capability of galloping. Finally, the wind tunnel experiment is carried out to test the wind energy harvesting performance by utilizing the harvester’s multi-modal characteristics. The results of this study demonstrate that the proposed harvester can harvest wind energy in multiple directions with the capability of galloping in multiple vibrational modes, and superior performance is achieved when the second bending mode is triggered. The novel design of the harvester from this work provides a viable solution for harvesting wind energy in a natural environment with varying wind conditions.
One-dimensional extended Su–Schrieffer–Heeger models as descendants of a two-dimensional topological model
Authors: Du Tao , Li Yue-Xun , Lu He-Lin , Zhang Hui 
Published: February 2024

Abstract
The topological phase diagrams and finite-size energy spectra of one-dimensional extended Su–Schrieffer–Heeger (SSH) models with long-range hoppings on the trimer lattice are investigated in detail. Due to the long-range hoppings, the band structure of the original SSH model becomes more complicated and new phases with the large Zak phase can emerge. Furthermore, a seeming violation of bulk-edge correspondence occurs in the one-dimensional topological system whose band topology stems from the inversion symmetry. The one-dimensional models are mapped onto a two-dimensional topological model when a parameter of the one-dimensional models is regarded as an additional degree of freedom. As Fourier components of the derived two-dimensional model, phase boudaries and the finite-size spectra of one-dimensional models can be recovered from the model in the higher spatial dimensions. Then the origin of edge modes of one-dimensional models can be understood from two dimensions and we give a reasonable explanation of the violation of bulk-edge correspondence in one spatial dimension. In fact, we may give a general perspective that the topological properties of one-dimensional (lower-dimensional) systems can be found their origin from two-dimensional (higher-dimensional) systems.
Analysis of the optical and electronic characteristics of Al/NiPc complex/p-Si diode
Authors: Güllü Ö , Efe U , Tataroğlu A 
Published: February 2024

Abstract
The primary goal of this work is to explore how the introduction of the Nickel (II) phthalocyanine tetrasulfonic acid tetrasodium salt (NiTsPc) organic interlayer influences the performance of conventional metal/semiconductor diodes. Firstly, the optical features of the NiTsPc organic film formed onto glass substrate were investigated. For this, the UV–vis spectroscopic data were used to determine various optical parameters like absorption coefficient (α), extinction coefficient (k), and refractive index (n). Then, Al/NiTsPc/p-Si diode was produced by forming ohmic and rectifier contact. The current–voltage (I-V) measurements were analyzed taking into account thermionic emission (TE) approach at room temperature. Device parameters such as ideality factor (η), barrier height (Φb), and resistance were investigated with the help of I-V technique. The Al/p-Si structure containing NiTsPc film showed good rectifying properties. In this analysis, Φb and η values were determined as 0.83 eV and 1.41, respectively, at room temperature. The device represents photovoltaic features with open-circuit voltage (Voc) of 0.37 V and a short-circuit current (Isc) of 8.17 μA under illumination of 100 mWcm−2. The results represent that the produced junction can be utilized in different photoelectric applications.
Characteristics mode analysis based wideband Sub-6 GHz flexible MIMO antenna using a unique hybrid decoupling structure for wearable applications
Authors: John Deepthi Mariam , Vincent Shweta , Pathan Sameena , Ali Tanweer 
Published: February 2024

Abstract
This article presents a compact flexible four-element multiple input multiple output (MIMO) antenna for Sub-6 GHz wearable applications. A wideband monopole antenna with a modified edge tapered radiator and a lowered ground plane is replicated to form a four-element antenna. The proposed antenna is fabricated on a flexible polyethylene terephthalate (PET) substrate and holds an overall dimension of 65 × 56 × 0.25 mm3. The antenna has a measured bandwidth of 3.55–5.3 GHz with a peak gain of 4.9 dBi. A novel hybrid decoupling structure with a neutralization line in the radiator and a unique defective ground structure (DGS) suppresses the coupling current and provides isolation better than −24 dB throughout the bandwidth. The antenna design evolution is explained using characteristics mode analysis (CMA). The MIMO diversity performance is relatively good with MIMO diversity metrics showing envelope correlation coefficient (ECC) < 0.001, diversity gain > 9.99, total active reflection coefficient (TARC) < −10 dB, channel capacity loss (CCL) < 0.3 bps Hz−1 and multiplexing efficiency (ME) < −0.5. Specific absorption rate (SAR) analysis of the antenna is performed to check the antenna’s suitability in wearable applications and the proposed antenna exhibits 0.745 W kg−1 and 0.326W kg−1 for 1g and 10g of tissue respectively which is much less than the permissible international standards.
Enhanced synergistic redox activity of SrCoS/PANI for hybrid energy storage and oxygen evolution reaction
Authors: Hassan Haseebul , Iqbal Muhammad Waqas , Akbar Saima , Afzal Amir Muhammad , Umar Ehtisham , Mohammad Saikh , Alothman Asma A , Ahmad Niaz , Elahi Ehsan 
Published: February 2024

Abstract
Supercapacitors (SCs) and secondary batteries (SBs) are commonly utilized for energy storage, although each has some limitations: low energy density (Ed) and power density (Pd), respectively. To address these issues, a hybrid supercapacitor is a new emerging technique known as supercapattery, which combines both of these devices to optimum the Ed and Pd in a single setting. The hydrothermal method was adopted to synthesize a cost-effective, eco-friendly, and non-toxic SrCoS/PANI, a composite material for optimum results of supercapattery. Crystallinity and morphology study of synthesized nanocomposites strontium cobalt sulfide with Polyaniline (SrCoS/PANI) were examined using SEM and XRD techniques. Initially, the performance was tested using a three-electrode setup of nanocomposites (SrCoS/PANI) in 1 M KOH electrolyte. The effectiveness of a SrCoS/PANI-activated carbon two-electrode supercapattery was examined through cyclic CV, GCD, and EIS techniques. In the two electrodes setup, the device performs admirably with an astonishing specific capacity of 139.4 C g−1, a high Ed of 29.56 Wh kg−1, and a high Pd of 800 W kg−1 at 1.0 A g−1. The cyclic stability was tested by putting the device through 5000 charging and discharging cycles, which maintained 91.65% of its Specific capacity (Qs). A hybrid nanocomposite (SrCoS/PANI) device was accomplished, with exceptional electrochemical capabilities at a low price making them a fascinating active material with potential applications in supercapattery technology. The electrocatalytic performance of the synthesized nanostructure (NSs) was studied comprehensively with regard to an oxygen evolution reaction (OER).
Improving the quality and properties of GaInSb crystal with Al doping
Authors: Wang Bowen , Liu Qiang , Liu Jian , Wang Chong , Liu Juncheng 
Published: February 2024

Abstract
GaInSb crystal is a promising substrate material that can be used to prepare various high-performance devices. Ga0.86In0.14Sb and Al-doped Ga0.86In0.14Sb (Ga0.86In0.14Sb:Al) crystals were grown with the vertical Bridgman method (VB). The doping concentration of aluminum (Al) is 0.005–0.015 molar ratio. The effect of Al doping on the structure and properties of Ga0.86In0.14Sb crystal was studied. The results indicated that Al doping significantly reduced the segregation of indium (In) component in the crystal, with the radial segregation reaching a minimum of 0.051 mol% mm−1 and the axial segregation reaching a minimum of 0.067 mol% mm−1. The doping of Al also improved the crystal quality (lattice structure integrity) of Ga0.86In0.14Sb. The passivation and compensation of Al on the intrinsic defects of Ga0.86In0.14Sb crystal significantly inhibited the generation of dislocation, of which density decreased to 2.461 × 103 cm−2. The doping of Al as the equivalent electron element of gallium (Ga) and In not only made the carrier concentration increase to 1.848 × 1018 cm−3 but also made the carrier mobility increase to 1.982 × 103 cm2/(V·s), resulting in the resistivity decreasing to 1.261 × 10−3 Ω·cm.
Quench dynamics of a Tonks-Girardeau gas in one dimensional anharmonic trap
Authors: Kumar Debnath Pankaj , Chakrabarti Barnali , Leslie Lekala Mantile 
Published: February 2024

Abstract
The quench dynamics of strongly interacting bosons on quartic and sextic traps are studied by exactly solving the time-dependent many-boson Schrödinger equation numerically. The dynamics are addressed by the key measures of one-body density in conjugate space and information entropy. For both cases, rich many-body dynamics are exhibited and the loss of the Bose–Fermi oscillation in the Tonks–Girardeau limit is also attributed.