bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Strategies to Promote High-quality Development of High-Tech Zones Industrial Economy in Shandong
Authors: Kong Ningning , Liu Wenhao , Zhang Jia , Wang Min
Published: September 2024

The high-tech zones is a concentrated distribution area of high-tech industrial clusters, which plays a key leading role in the high-quality development of industrial economy. This paper analyzes the current situation and existing problems of high-tech zones in Shandong Province in the development of industrial economy. Based on the above research, this paper puts forward some policy recommendations, such as speed up the cultivation of new quality productive forces, develop characteristic industries, etc. These suggestions may provide effective reference for the construction of high-tech zones in our province.
A review of Unveiling the Interconnections of Food- Energy- Water in Urban Environments
Authors: Qu Mengwen , Wang Xiaojian , Hong Xinhui
Published: September 2024

Food, energy and water are indispensable resources that meet basic human needs, and maintaining a balance among these resources is essential to ensure global food security and social stability. However, the climate is deteriorating with increasing severity due to global warming, and issues such as widespread food shortages, water pollution, and energy depletion are causing concerns across the globe. The nexus of foodenergy- water (FEW) has become the most pressing and complex issue to be addressed at present. This paper aims to provide a comprehensive and systematic review of recent research achievements and challenges in the field of FEW. It first introduces the concept of few and related policies, explores the challenges and crises of the FEW systems by different urban scales, and summarizes and concludes the research on the multivariate elements of the FEW nexus. At the end of the paper, based on the analysis of the previous literature, the paper identifies the urgent gaps and challenges that need to be addressed in future research.
Development of a mathematical model of dynamic soil deformation taking into account the variable coefficient of volumetric viscosity
Authors: Remez Natalya , Haiko Hennadii , Dychko Alina , Boiko Viktor , Haiko Svitlana , Antoniuk Olena
Published: September 2024

Determining soil deformations under the influence of dynamic loads of different nature, including during military actions, is an important scientific and practical problem. At the same time, when solving problems of determining the stress-strain state of soils under the action of short-term dynamic loads, little attention has been paid to the multicomponent composition and viscous properties. The aim of the research is to develop a mathematical model of soil deformation taking into account the variable coefficient of volumetric viscosity both during loading and unloading. The methods of mathematical modeling and numerical integration are used in the research. The possibility of using the proposed model to determine the deformation of soils under explosive and shock loads is shown, which helps control the properties of soils for the protection of shallow underground structures. The results of a comparison of the obtained analytical data with the experimental data are presented.
Integrating mining software, CAD, and GIS technologies for enhanced 3D geological mapping and visualization
Authors: Saganiak Kamil , Buketov Valentyn
Published: September 2024

This research provides a comprehensive overview of the methods and technologies applied for the mapping and visualization of three-dimensional (3D) mining and geological data, highlighting both mining-specific software and general-purpose engineering CAD and GIS tools. The study begins by addressing the challenges associated with the implementation of GIS-type spatial information systems within the mining industry, emphasizing their role in building robust information systems for mine technical departments. It then explores the application of spatial information systems in the environmental protection of mining and post-mining areas, where these technologies have found significant use. The final section delves into modern technologies for acquiring and visualizing spatial data, focusing on 3D data relevant to both surface and underground mining operations. The article underscores the growing importance of advanced visualization techniques in enhancing the accuracy and efficiency of mining operations and environmental management.
Comprehensive study on electric vehicles and infrastructure for sustainable development in Ukraine
Authors: Pivnyak Gennadiy , Olishevska Valentyna , Olishevskiy Hennadiy , Lutsenko Ivan , Lysenko Alexandra , Sala Dariusz
Published: September 2024

Purpose is a comprehensive study of the development of electric cars and related infrastructure for the period from 2010 to 2022 in Ukraine through the prism of global experience. The article studies the current state of development of electric vehicles in Ukraine in the transition from cars with internal combustion engines to electric vehicles. Electric cars in Ukraine are becoming increasingly popular. In terms of growth in sales of electric vehicles, Ukraine is ahead of such developed automotive countries as the United States and Japan. A study of the impact of electric vehicles on the development of related infrastructure in Ukraine has shown that the effective development of electric vehicles in Ukraine requires the creation of a special system for full-scale operation. This process involves car manufacturers, dealers, specialized service stations, manufacturers and installers of charging stations, government and financial institutions that provide additional benefits to owners of electric vehicles, as well as energy companies and battery recycling companies. The issues of ensuring the necessary capacity of electricity supply networks need to be further considered, taking into account the need to create a powerful network of charging stations for electric vehicles. Trends in the development of electric cars show that electric cars not only change the environment, but also create a new ecosystem, form economic models for the future of Ukraine.
Critical-Illness-Polyneuropathie und -Myopathie – Aktuelles zu
Diagnostik und Therapie
Authors: Balke Maryam
Published: September 2024

Die Critical Illness Polyneuropathie (CIP) und Critical Illness Myopathie (CIM)
bzw. Critical Illness Neuromyopathie (CINM) sind häufige Komplikationen einer
intensivmedizinischen Behandlung und werden oft unter dem Begriff der
intensive-care-unit-acquired weakness (ICU-AW) zusammengefasst. Die
Diagnosestellung erfolgt klinisch anhand der Prüfung von Kraft, der Sensibilität
und des Reflexstatus. Daneben helfen elektrophysiologische Untersuchungen und
Muskelsonografie bei der Diagnosestellung und Verlaufsbeobachtung. Bei der CIP
handelt es sich pathophysiologisch um eine Degeneration der Axone, bei der CIM
kommt es zu einer direkten Schädigung der Muskelfasern im Sinne einer primären
Myopathie. Die neuromuskuläre Dysfunktion nach intensivmedizinischer Behandlung
ist ein wichtiger Kofaktor der weiteren Morbidität und der Gesamtprognose der
Betroffenen. Eine intensivere Auseinandersetzung mit der Schädigung der Nerven
und Muskeln in der Frühphase der schweren Erkrankung wird uns helfen, unser
Verständnis von der Pathophysiologie und vom Verlauf der ICU-AW zu verbessern,
die Diagnose früher zu stellen, früher zu intervenieren und damit die Prognose
zu verbessern.
Diagnose des akuten Koronarsyndroms
Authors: Thießen Niklas , Schnabel Renate
Published: September 2024

Das akute Koronarsyndrom ist in vielen Fällen die erste klinische Manifestation der zugrunde liegenden Atherosklerose und stellt häufig eine Notfallsituation dar. In kurzer Zeit müssen die Ursache und ggf. mögliche Differenzialdiagnosen erkannt und zügig gehandelt werden. Die richtige Interpretation von Anzeichen und Symptomen und die entsprechende Auswahl der diagnostischen Methode sind die Basis für die weitere Therapie.
Pulmonary Metastasectomy after Immune Checkpoint Inhibitors in Renal Cell Carcinoma
Authors: Sakanoue Ichiro , Hamaji Masatsugu , Nakajima Daisuke , Date Hiroshi
Published: September 2024

The management of oligometastatic renal cell carcinoma with pulmonary metastases is controversial and occasionally requires multimodality management, including salvage pulmonary metastasectomy after immune checkpoint inhibitors (ICIs). However, limited data are available on these patients. We describe a case series of three consecutive patients who underwent salvage pulmonary metastasectomy after ICIs for oligometastatic renal cell carcinoma and discussed the important characteristics of these patients. After salvage pulmonary metastasectomy, none of the patients had recurrent pulmonary metastases, although one of them developed a brain metastasis postoperatively. Our case series suggests that salvage pulmonary metastasectomy after ICIs may control pulmonary metastases in carefully selected patients with oligometastatic renal cell carcinoma, although the management of extrapulmonary metastases may be required after salvage pulmonary metastasectomy.
Stakeholders’ views of online surveillance capabilities: a comparative analysis of the debates in UK, Finland and Norway
Authors: Leppänen Anna-Riitta , Flinterud Guro , Long Amy , O’Neill Megan , Boucht Johan , Schaefer Burkhard , Houtsonen Jarmo
Published: September 2024

We examine how stakeholders (n = 74) in the United Kingdom, Finland and Norway perceive security authorities’ online surveillance capabilities, and how these perceptions form patterns transcending national borders and organisational boundaries. Using a Q-methodological approach, we found variation within and between nations that is usually obscured in the polarised public debates. Furthermore, our stakeholders presented areas of consensus not usually apparent in public discourses. We argue for using awareness of this nuance and areas of convergence as platforms on which to build more effective public debates to further principles of deliberative democracy.
Research on improved YOLOV7-SSWD digital meter reading recognition algorithms
Authors: Cao Zhenguan , Yang Haixia , Fang Liao , Li Zhuoqin , Li Jinbiao , Dong Gaohui
Published: September 2024

Meter reading recognition is an important link for robots to complete inspection tasks. To solve the problems of low detection accuracy and inaccurate localization of current meter reading recognition algorithms, the YOLOV7-SSWD (YOLOV7–SiLU–SimAM–Wise-IoU–DyHeads) model is proposed, a novel detection model based on the multi-head attention mechanism, which is improved on the YOLOV7-Tiny model. First, the Wise-IoU loss function is used to solve the problem of sample quality imbalance and improve the model’s detection accuracy. Second, a new convolutional block is constructed using the SiLU activation function and applied to the YOLOV7-Tiny model to enhance the model’s generalization ability. The dynamic detection header is then built as the header of YOLOV7-Tiny, which realizes the fusion of multi-scale feature information and improves the target recognition performance. Finally, we introduce SimAM to improve the feature extraction capability of the network. In this paper, the importance of each component is fully verified by ablation experiments and comparative analysis. The experiments showed that the mAP and F1-scores of the YOLOV7-SSWD model reached 89.8% and 0.84. Compared with the original network, the mAP increased by 8.1% and the F1-scores increased by 0.1. The YOLOV7-SSWD algorithm has better localization and recognition accuracy and provides a reference for deploying inspection robots to perform automatic inspections.
Characteristic investigation of digital control four quadrant electro-hydrostatic actuator with separated hydraulic motor
Authors: Chen Xiaoming , Zhu Yuchuan , Ling Jie , Zhang Mingming
Published: September 2024

The asymmetric electro-hydrostatic actuator (EHA) is a promising distributed hydraulic actuation solution for the more-electric aircraft (MEA). However, the flow asymmetry is a common problem causing the poor position control accuracy and dynamics of EHA. To achieve good flow control in all quadrants and save energy in the assistive quadrants, a digital control four quadrant electro-hydrostatic actuator with a separated hydraulic motor using a novel four-quadrant division principle was proposed in this article. The theoretical model of the proposed EHA has been developed in MATLAB/Simulink and validated in the experiments. The theoretical results indicated that the increased external force allows the proposed EHA to have a constantly and partly linearly and varied motion velocity of the cylinder piston in the resistive and assistive quadrants, and the latter is determined by the specific external forces of 0.5 and 2.8 kN, respectively, in the extension and retraction quadrants. Compared with EHA without SHM, in the second and fourth quadrants, the energy dissipation is reduced by 104% and 36.7%, respectively, while the motion velocity of the cylinder piston is reduced by 12.9% and 25.6%, respectively. The theoretical and experimental results indicated that the proposed four quadrants division method effectively corrects the misjudgment of quadrants by using the existing four quadrants division method under the lower external force.
Linking excess entropy and acentric factor in spherical fluids
Authors: Yoon Tae Jun , Bell Ian H.
Published: September 2024

Introduced by Pitzer in 1955, the acentric factor (ω) has been used to evaluate a molecule’s deviation from the corresponding state principle. Pitzer devised ω based on a concept called perfect liquid (or centric fluid), a hypothetical species perfectly adhering to this principle. However, its physical significance remains unclear. This work attempts to clarify the centric fluid from an excess entropy perspective. We observe that the excess entropy per particle of centric fluids approximates −kB at their critical points, akin to the communal entropy of an ideal gas in classical cell theory. We devise an excess entropy dissection and apply it to model fluids (square-well, Lennard-Jones, Mie n-6, and the two-body ab initio models) to interpret this similarity. The dissection method identifies both centricity-independent and centricity-dependent entropic features. Regardless of the acentric factor, the attractive interaction contribution to the excess entropy peaks at the density where local density is most enhanced due to the competition between the local attraction and critical fluctuations. However, only in centric fluids does the entropic contribution from the local attractive potential become comparable to that of the hard sphere exclusion, making the centric fluid more structured than acentric ones. These findings elucidate the physical significance of the centric fluid as a system of particles where the repulsive and attractive contributions to the excess entropy become equal at its gas–liquid criticality. We expect these findings to offer a way to find suitable intermolecular potentials and assess the physical adequacy of equations of state.
Calculation and error analysis of virtual cathode caused by a thermionic cathode
Authors: Li Jian-Quan , Li Shu-Han
Published: September 2024

The relative errors of virtual cathodes calculated by using the one-dimensional virtual cathode theory are analyzed and discussed. The studies of the error analysis show that the cathode temperature is the major factor affecting the calculated results of virtual cathodes, especially for calculations of the virtual cathode width. The smaller the virtual cathode produced by a hot cathode, the more significant the relative error of the virtual cathode caused by the uncertainties of electron emission parameters. Using the accurate cathode temperature, the potential barrier and the spatial width of virtual cathodes generated by a tungsten filament are calculated with experimental and theoretical electron emission parameters. The calculated results show that there is a strong linear correlation between the potential barrier of the virtual cathode and the heating current of the tungsten filament, which is independent of the electron collection current. With the increase in the heating current, the variation of the virtual cathode width is very sensitive to the relation between the electron collection current and the heating current.
Measuring the topological charge of a vortex beam via the self-rotating beam phase
Authors: Shan Shengxiang , Cheng Shubo , Liu Shuo , Xiong Yan , Xu Yiping , Pan Han , Tao Shaohua , Yang Wenxing
Published: September 2024

We proposed a method to measure the topological charge of a vortex beam by using the self-rotating beam phase in this Letter. We investigated the far-field intensity patterns of the vortex beams passing through a phase hologram of the self-rotating beam with n = +2 theoretically and experimentally. The results demonstrate that the far-field intensity patterns cannot exhibit bright stripes when the topological charge of the vortex is positive (i.e., n ⋅ l > 0) and the calculated ratio relationship ξ can be used to identify the topological charge of the vortex beam. Differently, it can be found that the far-field intensity patterns exhibit several bright stripes when the topological charge of the vortex is negative (i.e., n ⋅ l < 0) and the number N of the bright stripes is equal to |l|−1(l represents the topological charge of the vortex beam). The experimental results are in good agreement with the theoretical ones. This method may inspire further research in the field of self-rotating beams.
The electrokinetic energy conversion analysis of viscoelastic Maxwell nanofluids with couple stress in circular microchannels
Authors: Zhang Yue , Zhao Guangpu , Hou Yaxin , Zhang Jiali , Xue Bo
Published: September 2024

The present study focuses on the unsteady flow of a viscoelastic Maxwell nanofluid with couple stress in a circular microchannel under the combined action of periodic pressure and magnetic field. The Green's function method is applied to the unsteady Cauchy momentum equation to derive the velocity field. We strive to check out the analytical solutions of the current model by validating them with existing results. In addition, the effects of several dimensionless parameters (such as the couple stress parameter γ, the Deborah number De, and the dimensionless frequency ω) on the streaming potential and the electrokinetic energy conversion (EKEC) efficiency of the three waveforms (cosine, square, and triangular) are portrayed via graphical illustrations. Within the range of parameters chosen in this study, the results demonstrate that increasing the value of the Deborah number or decreasing the dimensionless frequency can effectively enhance the streaming potential. The velocity field and EKEC efficiency are improved with increasing couple stress parameters. Furthermore, our investigation is extended to compare the EKEC efficiency for square and triangular waveforms when the couple stress parameters are set to 20 and 40, respectively. The results also indicate that increasing the couple stress parameter significantly improves the EKEC efficiency, particularly in the context of the square waveform. These findings will provide valuable assistance in the design of periodic pressure-driven microfluidic devices.
Effects of mosaic crystal instrument functions on x-ray Thomson scattering diagnostics
Authors: Gawne Thomas , Bellenbaum Hannah , Fletcher Luke B. , Appel Karen , Baehtz Carsten , Bouffetier Victorien , Brambrink Erik , Brown Danielle , Cangi Attila , Descamps Adrien , Goede Sebastian , Hartley Nicholas J. , Herbert Marie-Luise , Hesselbach Philipp , Höppner Hauke , Humphries Oliver S. , Konôpková Zuzana , Laso Garcia Alejandro , Lindqvist Björn , Lütgert Julian , MacDonald Michael J. , Makita Mikako , Martin Willow , Mishchenko Mikhail , Moldabekov Zhandos A. , Nakatsutsumi Motoaki , Naedler Jean-Paul , Neumayer Paul , Pelka Alexander , Qu Chongbing , Randolph Lisa , Rips Johannes , Toncian Toma , Vorberger Jan , Wollenweber Lennart , Zastrau Ulf , Kraus Dominik , Preston Thomas R. , Dornheim Tobias
Published: September 2024

Mosaic crystals, with their high integrated reflectivities, are widely employed in spectrometers used to diagnose high energy density systems. X-ray Thomson scattering (XRTS) has emerged as a powerful diagnostic tool of these systems, providing in principle direct access to important properties such as the temperature via detailed balance. However, the measured XRTS spectrum is broadened by the spectrometer instrument function (IF), and without careful consideration of the IF one risks misdiagnosing system conditions. Here, we consider in detail the IF of 40 and 100 μm mosaic Highly Annealed Pyrolytic Graphite crystals, and how the broadening varies across the spectrometer in an energy range of 6.7–8.6 keV. Notably, we find a strong asymmetry in the shape of the IF toward higher energies. As an example, we consider the effect of the asymmetry in the IF on the temperature inferred via XRTS for simulated 80 eV CH plasmas and find that the temperature can be overestimated if an approximate symmetric IF is used. We, therefore, expect a detailed consideration of the full IF will have an important impact on system properties inferred via XRTS in both forward modeling and model-free approaches.
Switching figure-of-merit, optimal design, and power loss limit of (ultra-) wide bandgap power devices: A perspective
Authors: Porter Matthew , Yang Xin , Gong Hehe , Wang Bixuan , Yang Zineng , Zhang Yuhao
Published: September 2024

Power semiconductor devices are utilized as solid-state switches in power electronics systems, and their overarching design target is to minimize the conduction and switching losses. However, the unipolar figure-of-merit (FOM) commonly used for power device optimization does not directly capture the switching loss. In this Perspective paper, we explore three interdependent open questions for unipolar power devices based on a variety of wide bandgap (WBG) and ultra-wide bandgap (UWBG) materials: (1) What is the appropriate switching FOM for device benchmarking and optimization? (2) What is the optimal drift layer design for the total loss minimization? (3) How does the device power loss compare between WBG and UWBG materials? This paper starts from an overview of switching FOMs proposed in the literature. We then dive into the drift region optimization in 1D vertical devices based on a hard-switching FOM. The punch-through design is found to be optimal for minimizing the hard-switching FOM, with reduced doping concentration and thickness compared to the conventional designs optimized for static FOM. Moreover, we analyze the minimal power loss density for target voltage and frequency, which provides an essential reference for developing device- and package-level thermal management. Overall, this paper underscores the importance of considering switching performance early in power device optimization and emphasizes the inevitable higher density of power loss in WBG and UWBG devices despite their superior performance. Knowledge gaps and research opportunities in the relevant field are also discussed.
Improving lattice-light-shift uncertainty of an 171Yb optical clock with optimized cooling and trapping lasers
Authors: Peng Chengquan , Zhang Tao , Sun Changyue , Qi Qichao , Jin Taoyun , Lei Shuai , Zhao Chengcheng , Feng Suzhen , Xia Yan , Xu Xinye
Published: September 2024

Atoms confined in the optical lattice can be interrogated with Doppler- and recoil-free operation. However, if not properly controlled, the optical lattice may limit clock accuracy. To improve the lattice-light-shift uncertainty, the cooling and trapping lasers' frequency stability is optimized, and the atom's signal stability is enhanced. A ring-cavity Ti:sapphire laser is locked to the optical frequency comb, which is referenced to a 578 nm ultra-stable laser, and the beat note's stability is on the order of 10−16. Using a 10 cm Fabry–Pérot cavity referenced to the Ti:sapphire laser, the optical frequency stability is transferred to the 399 nm cooling laser, creating favorable conditions for evaluating the lattice-light-shift accurately. We reevaluate lattice-light-shift in our 171Yb optical lattice clock with an uncertainty of 8.1 × 10−18, which is an order lower than our previous result, and the magic frequency is determined to be 394 798 266.6(1.3) MHz.
Unraveling impacts of polycrystalline microstructures on ionic conductivity of ceramic electrolytes by computational homogenization and machine learning
Authors: Peng Xiang-Long , Xu Bai-Xiang
Published: September 2024

The ionic conductivity at the grain boundaries (GBs) in oxide ceramics is typically several orders of magnitude lower than that within the grain interior. This detrimental GB effect is the main bottleneck for designing high-performance ceramic electrolytes intended for use in solid-state lithium-ion batteries, fuel cells, and electrolyzer cells. The macroscopic ionic conductivity in oxide ceramics is essentially governed by the underlying polycrystalline microstructures where GBs and grain morphology go hand in hand. This provides the possibility to enhance the ion conductivity by microstructure engineering. To this end, a thorough understanding of microstructure–property correlation is highly desirable. In this work, we investigate numerous polycrystalline microstructure samples with varying grain and grain boundary features. Their macroscopic ionic conductivities are numerically evaluated by the finite element homogenization method, whereby the GB resistance is explicitly regarded. The influence of different microstructural features on the effective ionic conductivity is systematically studied. The microstructure–property relationships are revealed. Additionally, a graph neural network-based machine learning model is constructed and trained. It can accurately predict the effective ionic conductivity for a given polycrystalline microstructure. This work provides crucial quantitative guidelines for optimizing the ionic conducting performance of oxide ceramics by tailoring microstructures.
Accelerated convergence via adiabatic sampling for adsorption and desorption processes
Authors: Desgranges Caroline , Delhommelle Jerome
Published: September 2024

Under isothermal conditions, phase transitions occur through a nucleation event when conditions are sufficiently close to coexistence. The formation of a nucleus of the new phase requires the system to overcome a free energy barrier of formation, whose height rapidly rises as supersaturation decreases. This phenomenon occurs both in the bulk and under confinement and leads to a very slow kinetics for the transition, ultimately resulting in hysteresis, where the system can remain in a metastable state for a long time. This has broad implications, for instance, when using simulations to predict phase diagrams or screen porous materials for gas storage applications. Here, we leverage simulations in an adiabatic statistical ensemble, known as adiabatic grand-isochoric ensemble (μ, V, L) ensemble, to reach equilibrium states with a greater efficiency than its isothermal counterpart, i.e., simulations in the grand-canonical ensemble. For the bulk, we show that at low supersaturation, isothermal simulations converge slowly, while adiabatic simulations exhibit a fast convergence over a wide range of supersaturation. We then focus on adsorption and desorption processes in nanoporous materials, assess the reliability of (μ, V, L) simulations on the adsorption of argon in IRMOF-1, and demonstrate the efficiency of adiabatic simulations to predict efficiently the equilibrium loading during the adsorption and desorption of argon in MCM-41, a system that exhibits significant hysteresis. We provide quantitative measures of the increased rate of convergence when using adiabatic simulations. Adiabatic simulations explore a wide temperature range, leading to a more efficient exploration of the configuration space.
A classical density functional theory for solvation across length scales
Authors: Bui Anna T. , Cox Stephen J.
Published: September 2024

A central aim of multiscale modeling is to use results from the Schrödinger equation to predict phenomenology on length scales that far exceed those of typical molecular correlations. In this work, we present a new approach rooted in classical density functional theory (cDFT) that allows us to accurately describe the solvation of apolar solutes across length scales. Our approach builds on the Lum–Chandler–Weeks (LCW) theory of hydrophobicity [K. Lum et al., J. Phys. Chem. B 103, 4570 (1999)] by constructing a free energy functional that uses a slowly varying component of the density field as a reference. From a practical viewpoint, the theory we present is numerically simpler and generalizes to solutes with soft-core repulsion more easily than LCW theory. Furthermore, by assessing the local compressibility and its critical scaling behavior, we demonstrate that our LCW-style cDFT approach contains the physics of critical drying, which has been emphasized as an essential aspect of hydrophobicity by recent theories. As our approach is parameterized on the two-body direct correlation function of the uniform fluid and the liquid–vapor surface tension, it straightforwardly captures the temperature dependence of solvation. Moreover, we use our theory to describe solvation at a first-principles level on length scales that vastly exceed what is accessible to molecular simulations.
Multi-objective optimization of Stinger PDC cutter breaking rock parameters under intrusion-cutting action using Taguchi-based gray relational analysis
Authors: Wang Minsheng , He Senlin , Xiong Chao , Wang Heng , Xuan Lingchao , Shi Huaizhong , Liao Hualin , Huang Zhongwei
Published: September 2024

To enhance the efficiency of the Stinger Polycrystalline Diamond Compact (PDC) cutter in breaking hard rocks, this study focuses on optimizing the cutter intrusion-cutting rock breaking parameters. A numerical calculation model for the rotational breaking of granite by a Stinger PDC cutter was established. A comprehensive statistical examination was performed to assess the influence of various factors on intrusion ability (IA), tangential force (TF), and mechanical specific energy (MSE). The Taguchi method was used to determine the optimal settings for each factor, while analysis of variance was employed to assess the significance and relative impact of these factors on the target outcomes. In addition, the multi-objective function was optimized using the gray relational analysis method. The primary process parameters obtained for the various performance characteristics are the cone top angle (α), the cone top radius (r), the cutter diameter (d), the cutter back inclination angle (β), and weight on bit (P). The impact ratios of these parameters are 6.20%, 7.66%, 3.93%, 17.20%, and 65.02%, respectively. The optimal geometrical parameters are α = 60°, r = 2 mm, and d = 15 mm, while the optimal working parameters are β = 30° and P = 800 N. In the optimal case, IA and MSE were reduced by 55.335% and 15.809%, respectively, compared to the initial case. Despite a 15.706% increase in TF, the overall GRG increased for all three evaluation criteria, with an overall increase in efficiency of 18.229%. The results of this paper can provide guidance for the design of Stinger cutter PDC drill bits.
Hindered intermolecular stacking of anti-parallel telomeric G-quadruplexes
Authors: Bertini Luca , Libera Valeria , Catalini Sara , Schirò Giorgio , Orecchini Andrea , Campanella Renzo , Arciuolo Valentina , Pagano Bruno , Petrillo Caterina , De Michele Cristiano , Comez Lucia , Paciaroni Alessandro
Published: September 2024

Telomeric G-quadruplexes (G4s) are non-canonical DNA structures composed of TTAGGG repeats. They are extensively studied both as biomolecules key for genome stability and as promising building blocks and functional elements in synthetic biology and nanotechnology. This is why it is extremely important to understand how the interaction between G4s is affected by their topology. We used small-angle x-ray scattering to investigate the end-to-end stacking of antiparallel telomeric G-quadruplexes formed by the sequence AG3(T2AG3)3. To represent the experimental data, we developed a highly efficient coarse-grained fitting tool, which successfully described the samples as an equilibrium mixture of monomeric and dimeric G4 species. Our findings indicate that the antiparallel topology prevents the formation of long multimeric structures under self-crowding conditions, unlike the hybrid/parallel structures formed by the same DNA sequence. This result supports the idea that the stacking of monomeric G-quadruplexes is strongly affected by the presence of diagonal loops.
Drag reduction in hypersonic flows with viscous compressible fluid–solid coupling: The role of elastic spikes and lateral jets
Authors: Wang Wen-Fan , Wang Zhi-Qiao , Mei Mei , Yuan Xin-Yi , He Yong , Wu Wei-Tao , Wang Ming-Chuan
Published: September 2024

This article introduces a novel fluid–solid interaction (FSI) method designed for high-speed flow scenarios, which addresses the intricate interactions between viscous compressible fluids and elastic solids. The proposed method, grounded in the finite volume method, balances computational efficiency and stability while accurately capturing fluid dynamics and structural elasticity. Validation against experimental and numerical data from previous studies confirmed the algorithm's effectiveness. The validated FSI model is applied to study drag reduction in elastic spikes with lateral jets under hypersonic conditions, highlighting significant changes in flow characteristics due to structural deformation and lateral jets. The study extensively examined the effects of jet total pressure, jet orifice position, and spike material density on drag reduction, deformation, and flow field characteristics. Key findings include the influence of compressible FSI on temperature, pressure, and drag distribution, the benefits of increased jet pressure ratio for thermal protection, the impact of jet position on flow characteristics, and the relationship between spike deformation and material density. This study offers valuable perspectives and effective strategies for structure design and minimizing aerodynamic resistance in superspeed fluid situations. Nevertheless, there are still obstacles to overcome, such as non-linear deformation, thermal coupling, and computational precision, highlighting the necessity for further enhancement of FSI techniques.
Undegradable dietary protein limits growth and carcass yields in crossbred Boer kids fed Desmanthus hay or Rhodes grass (Chloris gayana) hay supplemented with urea and/or cottonseed meal
Authors: Aoetpah A. , Gardiner C. , Gummow B. , Mialon A. , Walker G.
Published: September 2024

Context Low-protein tropical forages required protein supplementation, which might affect growth of meat goats. Aims This study was aimed to compare liveweight gain, carcass/non-carcass yields and meat quality in crossbred Boer kids fed isonitrogenous diets varying in undegradable (UDP) and rumen-degradable (RDP) dietary protein sources. Methods Twenty-five female crossbred Boer kids were randomly allocated into the following five dietary treatments: Rhodes grass (Chloris gayana) hay supplemented with urea (U), urea plus cottonseed meal (UCSM), cottonseed meal (CSM), gliricidia (Gliricidia sepium) (Gliri) or Desmanthus (Desmanthus leptophyllus) only (Desman). The diets were formulated to supply 135 and 195 g crude protein/kg DM for the two experiments. Experiment 1 lasted 78 days and the dietary UDP:RDP ratio (g/kg DM) was 35:102 (U), 37:100 (UCSM), 40:97 (CSM), 55:82 (Desman) and 46:91 (Gliri). Experiment 2 lasted 138 days and the dietary UDP:RDP ratio (g/kg DM) was 45:150 (U), 52:143 (UCSM), 58:137 (CSM), 83:112 (Desman) and 71:124 (Gliri) respectively. Data were subjected to one-way ANOVA and general linear model. Key results After 138 days of supplementation, the Desman goats had the highest liveweight gain (83 g/day) and heaviest cold carcass weight (12.1 kg) in Experiment 2. This was followed, in descending order, by CSM (58 g/day and 9.6 kg), UCSM (48 g/day and 7.8 kg), Gliri (41 g/day and 7.6 kg) and U (6 g/day and 6.0 kg). Heavier carcass weight was associated with larger eye-muscle area and fat depth at the 12th rib. Aus-meat Beef Colour Standard scores of 3–4 for the eye muscle of the Desman and CSM goats compared with scores of 1C-2 in the other goats meant that the darker meat in Desman and CSM diets was associated with heavier carcass weight and a more rapid rate of decline in carcass pH. Conclusions Crossbred Boer kids fed high dietary UDP had higher intakes of UDP, RDP, metabolisable protein (MP) and metabolisable energy (ME), even though an isonitrogenous diet was offered. The Desman kids had higher liveweight gain, heavier carcass yield, greater eye-muscle area, thicker fat depth and heavier mass of non-carcass components. Implications The higher liveweight gain and carcass/non-carcass yields for Desman goats than for others was associated with increased DM, UDP, RDP, MP and ME intakes.
Rapid growth and the evolution of complete metamorphosis in insects
Authors: Manthey Christin , Metcalf C. Jessica E. , Monaghan Michael T. , Steiner Ulrich K. , Rolff Jens
Published: September 2024

More than 50% of all animal species are insects that undergo complete metamorphosis. The key innovation of these holometabolous insects is a pupal stage between the larva and adult when most structures are completely rebuilt. Why this extreme lifestyle evolved is unclear. Here, we test the hypothesis that a trade-off between growth and differentiation explains the evolution of this novelty. Using a comparative approach, we find that holometabolous insects grow much faster than hemimetabolous insects. Using a theoretical model, we then show how holometaboly evolves under a growth-differentiation trade-off and identify conditions under which such temporal decoupling of growth and differentiation is favored. Our work supports the notion that the holometabolous life history evolved to remove developmental constraints on fast growth, primarily under high mortality.
Dietary Herbs: Ancient Use, Modern Advancements and Health Prospects in the 21st Century
Authors: Arooj Misha , Khalid Nauman
Published: September 2024

As the World seeks sustainable and holistic approaches to health, dietary herbs are in the spotlight due to their potential benefits. Incorporating dietary herbs into functional products to create fortified foods with enhanced nutritional values has shown health benefits. Dietary herbs and diets rich in plant-based foods and supplements have been integral to managing diseases since ancient times. In the 21st century, research advancements in dietary herbs continue to analyse and characterize bioactive compounds to develop novel herbal formulations. This case study provides an overview of the historical use of dietary herbs, highlighting their bioactive compounds and the scientific evidence of those bioactive compounds in improving health and wellness.

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© The Authors 2024
The analytical approach in testing the Kaniadakis cosmology
Authors: Salehi A
Published: September 2024

We know that a quantum-corrected cosmological scenario can emerge based on its corrected Friedmann equations corresponding to the corrected entropy of cosmic-horizon using the gravity-thermodynamics conjecture in deriving those equations. In this right, the Kaniadakis entropy associated with the apparent horizon of Friedmann–Robertson–Walker (FRW) Universe leads to a corrected Friedmann equation which contains a correction term as

Ω

K
a

=

α

(

H
2

+

k

a
2

)

−
1

H

2

where

α
≡

K
2

π
2

2

G
2

(K is the Kaniadakis parameter). Here, we derive the analytical relations between the energy density parameters

Ω

m

,

Ω

Λ

(and the ratio density Ω

Ka
of correction term) and the geometrical cosmological parameters

{
q
,
j
}

. This leads to getting

Ω

K
a

=

j
−
1

4
(
q
+
1

)

2

−
(
j
−
1
)

which enables us to put constrains on

Ω

K

a

0

using the measurable parameters

{

q

0

,

j

0

}

and H
0. It also reveals some interesting aspects of the Kaniadakis cosmology by explaining that the correction term plays different roles both in the presence and in the absence of the cosmological constant Λ. This term plays the role of dark energy in the absence of the cosmological constant Λ, while in the presence of this component, it plays the role of a small correction to dark energy. The value of Ω

Ka
then determines the amount of the deviation of Kaniadakis model from the concordance ΛCDM model. As a result, the value of j
0 is found to be close to unit for vanishing cosmological constant

Λ
=
0

and the maximum value of

Ω

K
a
0

; thereby we get

(

j

0

−
1
)
≃
0.137

and

(

j

0

−
1
)
≃<

10

−
3

for the case of

Λ
=
0

and

Λ
≠
0

, respectively. That is, the jerk parameter j can be used as a useful tool to test the Kaniadakis cosmology using the observational studies.
Matter coupled to 3d quantum gravity: one-loop unitarity
Authors: Livine Etera R , Maris Valentine
Published: September 2024

We expect quantum field theories for matter to acquire intricate corrections due to their coupling to quantum fluctuations of the gravitational field. This can be precisely worked out in 3d quantum gravity: after integrating out quantum gravity, matter fields are effectively described as noncommutative quantum field theories, with quantum-deformed Lorentz symmetries. An open question remains: Are such theories unitary or not? On the one hand, since these are effective field theories obtained after integrating out high energy degrees of freedom, we may expect the loss of unitarity. On the other hand, as rigorously defined field theories built with Lorentz symmetries and standing on their own, we naturally expect the conservation of unitarity. In an effort to settle this issue, we explicitly check unitarity for a scalar field at one-loop level in both Euclidean and Lorentzian space-time signatures. We find that unitarity requires adding an extra-term to the propagator of the noncommutative theory, corresponding to a massless mode and given by a representation with vanishing Plancherel measure, thus usually ignored in spinfoam path integrals for quantum gravity. This indicates that the inclusion of matter in spinfoam models, and more generally in quantum gravity, might be more subtle than previously thought.
Research on novel hybrid structure AACMM based on 3-RPS parallel mechanism
Authors: Huang Hao , Wang Wen , Song Meng , Dong Quan , Lu Keqing , Shi Guang , Wang Chuanyong , Chen Zhanfeng
Published: September 2024

The articulated arm coordinate measuring machine (AACMM), widely utilized in the field of industrial measurement, is assessed based on key performance indicators such as measurement accuracy, measurement space, and flexibility. To enhance these aspects of the AACMM, this paper introduces a novel type of AACMM. The new model is based on a 3-RPS (revolute joint R, prismatic joint P, spherical joint S) parallel mechanism (3-RPSPM). The working principle of the 3-RPSPM is detailed, and a corresponding computational model is established. An algorithm is proposed based on this mathematical model to determine the theoretical achievable accuracy of the 3-RPSPM. Additionally, a spatial error analysis of the 3-RPSPM is conducted to verify its compliance with AACMM accuracy requirements and to demonstrate a certain level of accuracy improvement. Through simulation analysis, the differences in measurement accuracy, measurement space, and flexibility between the new type of AACMM based on the 3-RPS parallel mechanism (3-RPSAACMM) and traditional AACMMs are compared. The results indicate that the 3-RPSAACMM, with its novel parallel structure free from series accumulation errors, not only maintains measurement flexibility but also achieves improvements in measurement accuracy and space. The hybrid structure adopted by the new 3-RPSAACMM offers a new direction for the future development of AACMMs, presenting significant research value and application prospects.
Applying machine learning to optical metrology: a review
Authors: Xue Ruidong , Hooshmand Helia , Isa Mohammed , Piano Samanta , Leach Richard
Published: September 2024

This literature review investigates the integration of machine learning (ML) into optical metrology, unveiling enhancements in both efficiency and effectiveness of measurement processes. With a focus on phase demodulation, unwrapping, and phase-to-height conversion, the review highlights how ML algorithms have transformed traditional optical metrology techniques, offering improved speed, accuracy, and data processing capabilities. Efficiency improvements are underscored by advancements in data generation, intelligent sampling, and processing strategies, where ML algorithms have accelerated the metrological evaluations. Effectiveness is enhanced in measurement precision, with ML providing robust solutions to complex pattern recognition and noise reduction challenges. Additionally, the role of parallel computing using graphics processing units and field programmable gate arrays is emphasised, showcasing their importance in supporting the computationally intensive ML algorithms for real-time processing. This review culminates in identifying future research directions, emphasising the potential of advanced ML models and broader applications within optical metrology. Through this investigation, the review articulates a future where optical metrology, empowered by ML, achieves improved levels of operational efficiency and effectiveness.
Nonlinear vibration characteristics of a rotor-bearing system with disc–shaft insufficient interference and flexible coupling misalignment fault
Authors: Ma Xingfu , Li Zhinong , Chen ChangZheng , Huang Fengchao
Published: September 2024

For a traditional rotor system, looseness faults caused by disc–shaft insufficient interference are always ignored. Considering disc–shaft looseness caused by insufficient interference, a novel dynamic model of a rotor-bearing system in the presence of coupling misalignment is established in this paper to investigate the characteristics of a disc–shaft looseness fault. Due to the nonlinearity of the contact model between disc and shaft, iterative solution of kinetic equations can be obtained by combining the Newmark-β and Newton–Raphson methods. The vibration characteristics of a rotor-bearing system with and without disc–shaft looseness caused by insufficient interference are compared and analyzed. The results show that a slight collision between disc and shaft can be caused in a disc–shaft early looseness fault, and beat vibration of the systems appears when disc–shaft looseness becomes severe. Considering the effect of coupling misalignment, the vibration responses of a system under different coupling misalignments are further discussed, and parallel misalignment is proved to have a significant effect on disc–shaft looseness. It is expected that these research results will provide a useful reference for the identification and diagnosis of looseness faults caused by disc–shaft insufficient interference.