bluuebunny/crossref_metadata_2025_split huggingface dataset:
Community-Based Tourism Initiatives as a Tool for Empowering Indigenous Communities: Evidence from the Yucatan Peninsula, Mexico
Authors: Lazic Stefan , Gasparini Maria Laura 
Published: December 2023

Summary
Community-based tourism (CBT) is seen as an opportunity for equitable development and sharing of benefits among host community members. It is an alternative to the mass tourism phenomenon and a way to introduce sustainable management of natural resources. Tourism social enterprises often accompany CBT initiatives, emphasising the social force of tourism as an activity. They enable communities to address social issues while developing market-based activities, deal with injustice in tourism, and respond to the capitalist development strategies applied in the so-called major destinations.
In this work, we explore four indigenous community-based initiatives in the hinterland of the Yucatan Peninsula, one of Mexico’s main tourist areas. Through a fieldwork case study approach, we examine the internal governance of these initiatives, the role of external actors and the community approach to developing conscious tourism activities that support local livelihoods, value cultural heritage, and safeguard the natural environment. We find that tourism creates a spillover effect by providing opportunities for the development of complementary economic activities, decreasing the dependence on a single sector. Concurrently, tourism development empowers women and youth members of the communities by creating the possibilities for them to take leading roles in different activities.

Information
© The Authors 2023
AdS3 Einstein gravity and boundary description: pedagogical review
Authors: Ma Chen-Te 
Published: December 2023

Abstract
We review the various aspects of the 3D Einstein gravity theory with a negative cosmological constant and its boundary description. We also explore its connections to conformal field theories (CFTs), modular symmetry, and holography. It is worth noting that this particular theory is topological in nature, which means that all the physical degrees of freedom are located on the boundary. Additionally, we can derive the boundary description on a torus, which takes the form of a 2D Schwarzian theory. This observation suggests that the relevant degrees of freedom for the theory can be described using this 2D theory. Because of the renormalizability of the 3D gravity theory, one can probe the quantum regime. This suggests that it is possible to investigate quantum phenomena. Unlike the conventional CFTs, when considering the AdS3 background, the boundary theory loses modular symmetry. This represents a departure from the usual behavior of CFT and is quite intriguing. The Weyl transformation induces anomaly in CFTs, and we indicate that applying this transformation to the 2D Schwarzian theory leads to similar results. Summing over all geometries with the asymptotic AdS3 boundary condition is equivalent to summing over a modular group. The partition function is one-loop exact and therefore an analytical expression from the summation. This theory holds potential applications in Quantum Information and is a recurring theme in the study of holography, where gravitational theories are connected with CFTs.
Enhanced carrier densities in two-dimensional electron gas formed at BaSnO3/SrTaO3 and SrSnO3/SrTaO3 interfaces
Authors: Mahatara Sharad , Comes Ryan , Kiefer Boris 
Published: December 2023

Abstract
Two-dimensional electron gases (2DEGs) realized at perovskite oxide interfaces offer great promise for high charge carrier concentrations and low-loss charge transport. BaSnO3 (BSO) and SrSnO3 (SSO) are well-known wide bandgap semiconductors for their high mobility due to the Sn-5s-dominated conduction band minimum (CBM). Ta4+ with a 5d1
valence configuration in SrTaO3 (STaO) injects the d1
electron across the interface into the unoccupied Sn-5s states in BSO and SSO. The present study uses ACBN0 density functional theory computations to explore charge transfer and 2DEG formation at BSO/STaO and SSO/STaO interfaces. The results of the ACBN0 computations confirm the Ta-5d to Sn-5s charge transfer. Moreover, the Sn-5s-dominated CBM is located ∼1.4 eV below the Fermi level, corresponding to an excess electron density in BSO of ∼1.5 × 1021 cm−3, a ∼50% increase in electron density compared to the previously studied BSO/SrNbO3 (SNO) interface. Similarly, the SSO/STaO interface shows an improvement in interface electron density by ∼20% compared to the BSO/SNO interface. The improved carrier density in SSO/STaO and BSO/STaO is further supported by ∼13% and ∼15% increase in electrical conductivities compared to BSO/SNO. In summary, BSO/STaO and SSO/STaO interfaces provide novel material platforms for 2DEGs formation and ultra-low-loss electron transport.
Uncertainties estimation in surveying measurands: application to volumes
Authors: Covián E , Puente V , Casero M , Cienfuegos Suárez P 
Published: December 2023

Abstract
Volume represents a measurand of great interest in civil engineering and construction works. The estimation of this measurand is a problem already solved by surveying engineering, but the quantification of its uncertainty has been overlooked. As a result, the inaccurate estimation of the volume can lead to significant deviations in the execution costs of earthworks. Moreover, it is not possible to comply with the internationally accepted requirements concerning the expression of measures with an indication of its uncertainty, i.e. the guidelines of the Bureau International des Poids et Mesures. In this context, this paper presents a methodology for the quantification of uncertainty in the surveying measurement of volumes, which is generally carried out through digital terrain models processed by computer-aided design or specific surveying software. Two methods for volume estimation are presented and the variance–covariance propagation laws are applied to each of them, leading to the computation of volume uncertainty from measures of position coordinates for which uncertainties are known. Then, the developed methods for uncertainty estimation are successfully tested in different scenarios. The conceptual and mathematical developments for the uncertainty quantification in the computation of volumes resulted in closed-form algorithms implemented in MATLAB that can be potentially incorporated into commercial surveying software.
Geological detection of hard rocks by GPR and signal time-frequency characteristics analysis in urban underground trenchless construction
Authors: Zhang Liang , Zhang Sheng , Deng Zongwei , Ling Tonghua 
Published: December 2023

Abstract
The hard rocks in the stratum can pose safety risks and hinder the progress of urban underground tunnel construction using shield and jacking methods, thereby reducing construction efficiency and increasing construction costs. This paper utilizes wavelet scale energy spectrum, wavelet packet theory and statistical methods to conduct research on the detection of special geological formations such as hard rocks and voids, as well as the analysis of their signal time-frequency characteristics based on the ground-penetrating radar (GPR) technique. On the basis of calibrating the permittivity of different types of rock blocks, we established a forward model for detecting hard rocks and voids, and the simulated signals were analyzed in the time and frequency domains. Subsequently, laboratory experiments were conducted to perform GPR tests on different types of hard rocks in natural and water-saturated states and voids, to explore the time-frequency characteristics, frequency band energy variations, and statistical patterns of typical single-trace signals. The results show that the granite detection signal contains more low-frequency components, the sandstone detection signal contains more medium-low frequency components, while the limestone detection signal contains more medium-high frequency components in their natural state; the signal from the karst cave has relatively more low-frequency components than the signal from the empty cavity. The geometric shape of the rock has no influence on the dominant frequency and time-frequency distribution of its reflection signal. Generally, rocks with higher rebound values (hardness) also exhibit larger variance and standard deviation in frequency band energy. The research has important theoretical significance and practical value for the measurement and assessment of special geological features such as hard rocks and voids in urban underground trenchless construction.
Automated defect detection in precision forging ultrasonic images based on deep learning
Authors: Zhao Jianjun , Zhang Yuxin , Du Xiaozhong , Sun Xiaoming 
Published: December 2023

Abstract
Ultrasonic testing is a widely used non-destructive testing technique for precision forgings. However, assessing defects in ultrasonic B-scan images can be prone to errors, misses, and inefficiencies due to human judgment. To address these challenges, we propose a method based on deep learning to automate the evaluation of such images. We started by creating a dataset comprising 8000 images, each measuring 224 × 224 pixels. These images were cropped from ultrasonic B-scan images of 7 specimens, each featuring different sizes and locations of holes and crack defects. We then used state-of-the-art deep learning models to benchmark the dataset and identified YOLOv5s as the best-performing baseline model for our study. To address the challenges of deploying deep learning models and the issue of small defects being easily confused with the background in ultrasonic B-scan images, we made lightweight improvements to the deep learning model. Additionally, we enhanced the quality of data labels through data cleaning. Our experiments show that our method achieved a precision of 97.8%, a recall of 98.1%, mAP@0.5 of 99.0%, and mAP@.5:.95 of 67.6%, with a frames per second (FPS) of 74.5. Furthermore, the number of model parameters was reduced by 43.2%, while maintaining high detection accuracy. Overall, our proposed method offers a significant improvement over the original model, making it a more reliable and efficient tool for automated defect assessment in ultrasonic B-scan images.
Dynamic digging force modeling and comparative analysis of backhoe hydraulic excavators
Authors: Li Tianyu , Ren Zhigui , Pang Xiaoping , Chen Dingjun , Cao Shusheng 
Published: December 2023

Abstract
The evaluation of excavator performance relies heavily on digging force, which serves as a crucial indicator. However, the accuracy of performance assessment is hindered by the absence of a suitable method to characterize the dynamic digging capacity of excavators. This study addresses this limitation by proposing an approach to establish a set of solution-limited inequalities for dynamic digging force. The approach incorporates D’Alembert’s principle and composite digging, while considering the influence of inertia force. Furthermore, to mitigate the issue of bucket tooth tip trajectory shaking caused by discontinuous posture during excavation, an amount of measurement data from a 20-ton machine is utilized to construct a consistent theoretical digging trajectory. The theoretical trajectory is subjected to numerical verification to determine the dynamic digging force along the trajectory. A comparative analysis is then conducted, contrasting the obtained dynamic digging force with different theoretical digging forces and measured resistances. Additionally, the dynamic digging forces within the selected digging area of the machine are characterized, without accounting for attitude continuity. The findings demonstrate that the dynamic digging force effectively captures the excavator’s performance along the trajectory, and it also provides an excellent characterization of the digging force at discrete digging spots.
EWSeg: a fast segmentation algorithm for images based on edge linking and watershed constraints
Authors: Ding Weili , Zhang Zhipeng , Guo Xinya , Su Liancheng , Hua Changchun 
Published: December 2023

Abstract
In this paper, we propose a two-stage algorithm, named watershed-constrained image segmentation, for exploring complete edge-closed regions from edges. In the first stage, the input image is pre-processed and the image gradient information is obtained using a gradient operator. Anchors are then obtained from the gradient information. Finally, initial edges are obtained by intelligently connecting the anchors. In the second stage, a marker-based watershed algorithm is adopted to obtain marker points from the gradient information obtained in the first stage. A Gaussian filtered image is then used as the input image to obtain a watershed hyper-segmented edge map. Finally, complete edge-closed regions are obtained by combining the initial edges and the hyper-segmented edge map and searching for weak edges. The image segmentation results are then obtained from the edge-closed regions, demonstrating the excellent performance of our proposed algorithm on various images and videos.
High-precision point cloud registration method based on volume image correlation
Authors: Wang Lianpo 
Published: December 2023

Abstract
With the rapid development of binocular reconstruction, fringe projection profilometry, and time of flight, 3D imaging technology has been widely applied in the field of 3D measurement. However, due to limited measurement range and self-occlusion, point cloud registration methods are often used to obtain larger or more complete 3D contours. Although many scholars have proposed various point cloud registration methods, the accuracy and efficiency of point cloud registration still need to be further improved, especially for point clouds with different density or non-rigid transformation. Image registration technology based on image correlation has been developed for many years and has achieved great success in fields such as computer vision, photomechanics, and photogrammetry. Therefore, a simple and direct idea in this paper is to transform the point cloud registration problem into volume image correlation problem. By this, an efficient image registration method based on fast Fourier transform and an inverse compositional Gaussian Newton optimization method that only needs to calculate the Hessian matrix once can be introduced into the point cloud registration field, which can greatly improve the speed and accuracy of point cloud registration. Comparative experiments have shown that our method has doubled the accuracy and efficiency compared to the iterative closest point (ICP) method, and its practicality has also been verified in impeller reconstruction experiments.
Manipulating helical phase of HHG vortex with atomic states
Authors: Liu Kecheng , Zhang Guizhong , Zhang Shenghua , Shi Wei , Yao Jianquan 
Published: December 2023

Abstract
By deploying the strong-field approximation theory, we perform numerical simulation on atomic high-order harmonic generation (HHG) of hydrogen and HHG vortices generated by hydrogen layer. Our results show that the atomic HHG spectra demonstrate peak-shifting and the helical phase of the HHG vortex can be manipulated with initial states of atoms, all ionized by oppositely polarized bicircular ω and 2ω Laguerre–Gaussian fields. The HHG peaks shift to higher frequency by ω if the initial state is switched from

ψ

100

to

ψ

211

, and the HHG peaks shift to lower frequency by ω if the initial state is switched from

ψ

100

to

ψ

21
−
1

, the final state is always the ground state

ψ

100

. The helical phase patterns of the HHG vortices are investigated in connection with the atomic HHG peak-shifting and the angular momentum conservation law. In addition, we observe that the fourth HHG harmonic is strongly dependent on the 2ω field but weakly on the ω field for an initial atomic state of magnetic quantum number −1.
X-ray single photon detection with XPOL-III
Authors: Sgrò Carmelo , Baldini Luca , Bellazzini Ronaldo , Brez Alessandro , Ceccanti Marco , Latronico Luca , Lucchesi Leonardo , Manfreda Alberto , Minuti Massimo , Orsini Leonardo , Pesce-Rollins Melissa , Pinchera Michele , Profeti Alessandro , Spandre Gloria 
Published: December 2023

Abstract
XPOL-III is a newly developed CMOS ASIC simultaneously working for
collecting charge and processing signals inside Gas Pixel Detectors (GPD).
Starting from the architecture of the XPOL ASIC and its successful
operation in the IXPE space mission, we implemented specific design changes
aiming at increasing the rate capability and the uniformity of response.
XPOL-III includes more than 100k pixels at 50 μm pitch in a total active area of about
15 × 15 mm2. Each pixel acts as a charge-collecting anode and is connected to its
charge-sensitive amplifier, followed by a shaping circuit and a sample-and-hold system. The
chip, like its predecessor, provides self-triggering capability, with automatic localization of
the region of interest (ROI) to be readout for each single photon. A new programmable
definition of the margin pixels around the ROI was implemented to reduce readout time. Other
improvements include the sensitivity of the trigger electronics and an increase in the maximum
speed for the serial event readout.
In this work we describe the design of this new ASIC and the results of its preliminary tests, in particular in the context of the gas detector application, in which imaging the photoelectron track emitted by single X-ray absorption allows us to measure beam polarization together with timing, imaging, and spectroscopy.
Characterization study of NaI(Tl) γ-summing spectrometer
Authors: Sharma Sathi 
Published: December 2023

Abstract
The accurate information regarding the β-decay
half-life, feeding pattern from the neutron-rich nuclei have utmost
importance in the field of nuclear waste management from the fission
reactors as well as correct understanding about the r-process
nucleosynthesis in stellar sites. The low capture cross-section
measurements are also considered as major task by experimental
nuclear astrophysicists. These kinds of measurements are really
difficult with conventional high-resolution gamma spectroscopy
techniques due to less efficiency of the detectors. For this
purpose, we have an almost 4π γ-summing NaI(Tl)
spectrometer at SINP, Kolkata. It is basically a cylindrical shaped
detector with six sectors of NaI(Tl) crystals read by 6
photomultiplier tubes (PMT) at one end. The detailed
characterization of the spectrometer via experiment using laboratory
standard sources and GEANT4 simulation model to interpret all the
interesting properties will be presented here in this paper.
Limit shapes from harmonicity: dominos and the five vertex model
Authors: Kenyon Richard , Prause István 
Published: December 2023

Abstract
We discuss how to construct limit shapes for the domino tiling model (square lattice dimer model) and five-vertex model, in appropriate polygonal domains. Our methods are based on the harmonic extension method of Kenyon and Prause (2022 Duke Math J.
171 3003–22).
Potential waste from felling of Eucalyptus pellita trees using Komatsu PC130F-7 in industrial plantation forest
Authors: Ruslim Y , Astuti N M , Sari D R 
Published: December 2023

AbstractEast Kalimantan has seen an increase in mechanized harvesting methods in recent years. Timber production activities in Surya Hutani Jaya Industrial Plantation Forest, Sebulu District have implemented a mechanical harvesting system, including tree felling activities. In the harvesting system by mechanical means, the presence of felling waste is inseparable. Therefore, the volume of felling waste from stumps, stems, and tree tops was calculated. From the stump waste with an area of 0.25 ha in the research plot, 50 samples were taken with a volume produced of 0.0427 m3or 0.1707 m3ha−1. In stem waste, 10 samples were taken with a total volume produced of 0.0453 m3or 0.1811 m3ha−1. From the tree top waste, 50 samples were taken with a total volume produced of 0.0374 m3or 0.1496 m3ha−1. Waste stump, stem, and tree top waste amounted to 0.5014 m3ha−1or 0.45%. The results of this study used the Komatsu PC130F-7, the lowest remaining stump height was 1.7 cm and the highest was 12.6 cm. Meanwhile, the mean stump height is only 5.44 cm. From research, it is known that this company has been able to carry out logging efficiently because the waste produced has a relatively small value. The advantage of harvesting trees with a Komatsu PC 130F-7 equipped with a shearing head is the minimum amount of wood debris that accumulates in the field.
Object Oriented Design Systems for WebGIS Flood Risk Classification in Samarinda, Indonesia
Authors: Agus F , Kamil Z A , Gifari O I 
Published: December 2023

Abstract
Floods are a prevalent environmental concern that frequently impacts urban regions. In conjunction with the growth of urbanization, the expansion of urban areas frequently gives rise to issues related to flooding. Samarinda, the administrative center of East Kalimantan Province, is intrinsically linked to the problems of flooding and waterlogging. The occurrence of floods in this urban area is frequently observed during periods of heavy rainfall and elevated water discharge from the Mahakam River and its associated tributaries. The utilization of the Web Geographics Information System to present maps depicting areas susceptible to flooding serves as a digital instrument and informational resource for urban communities. This research aims to design and implement WebGIS software for the classification of flood-prone regions in Samarinda City, employing the Object-Oriented Design System (OODS) approach. The process of flood classification modeling involves the utilization of various factors, including rainfall data, road kinds, slope gradients, and land use types. The design of this WebGIS system incorporates OODS principles, utilizing the Unified Modeling Language (UML) methodology. This approach encompasses many UML techniques, including Use Case Diagrams, Class Diagrams, and Entity Relationship Diagrams. The outcome of this study resulted in the design and implementation of the WebGIS program, which serves the purpose of classifying flood-prone areas in Samarinda City. This result encompasses object designs and interfaces that visually represent flood zones on a map. The system validation test was conducted by comparing the classification results and historical flood data, with a result of 90%.
Antibacterial and biolarvicidal activity of extracts of ethanol of Goniothalamus macrophyllus leaves and roots
Authors: Kurniawan D , Kustiawan P M , Pramaningsih V , Yuliawati R , Ismiati R 
Published: December 2023

Abstract
Tendani (Goniothalamus macrophyllus) is empirically often used by Dayak people as a mosquito repellent by burning the stem bark and roots which have the ability as anti-bacterial. The objective of this research is to evaluate the antibacterial and biolarvicidal properties of ethanol extracts of Goniothalamus macrophyllus’s leaves and roots. The research method used qualitative method with colour phytochemical test, antibacterial test, and larvicidal test. Based on the study of active compounds contained in G. macrophyllus, the results of colour phytochemical tests of ethanol extracts of leaves and roots all contain compounds of the alkaloid, flavonoid, triterpenoid/steroid, saponin, tannin and phenol groups. The results of the antibacterial tests on the leaves and roots have a strong ability to inhibit the growth of Candida albicans, Propionibacterium acne and Streptococcus mutans. The highest larval mortality rate in the biolarvicide test was obtained in the root part of tendani with a concentration of 15% at 88%. The conclusion of the study is that the leaves and roots of the tendani plant have potential as antibacterial and biolarvicidal.