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Chinese Physics B 2024年第7期33卷 419-428页

作者： Jackson pame Lenin SShagolsem Department of Physics National Institute of Technology ManipurImphalIndia

w. study the effect of particle size polydispersity(δ) on the melting transition(T*), local ordering, solid–liquid coexistence phase and dynamics of tw.-dimensional Lennard–Jones fluids up to moderate polydispersity by means of computer simulations. The particle sizes are draw. at random from the Gaussian(G) and uniform(U) distribution *** these systems, w. further consider tw. different kinds of particles, viz., particles having the same mass irrespective of size, and in the other case the mass of the particle scales w.th its size. It is observed that w.th increasing polydispersity,the value of T*initially increases due to improved packing efficiency(φ) follow.d by a decrease and terminates at δ ≈8%(U-system) and 14%(G-system) w.th no significant difference for both mass types. The interesting observation is that the particular value at w.ich φ drops suddenly coincides w.th the peak of the heat capacity(CP) curve, indicating a transition. The quantification of local particle ordering through the hexatic order parameter(Q_6), Voronoi construction and pair correlation function reveals that the ordering decreases w.th increasing δ and T. Furthermore, the solid–liquid coexistence region for the G-system is show. to be comparatively w.der in the T –δ plane phase diagram than that for the U system. Finally, the study of dynamics reveals that polydisperse systems relax faster compared to monodisperse systems;how.ver, no significant qualitative differences, depending on the distribution type and mass polydispersity, are observed.

关键词： polydispersity ordering phase diagram dynamics

Chirality enables thermal magnon transistors

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 161-166页

作者： Tao Yu Chengyuan Cai Gerrit e.w.Bauer School of Physics Huazhong University of Science and TechnologyWuhan 430074China .w.I-AIMR and Institute for Materials Research and SCIS Tohoku UniversitySendai 980-8577Japan Kavli Institute for Theoretical Sciences University of Chinese Academy of SciencesBeijing 100190China

w. report a theory of thermal spin pumping into proximity magnets under a transverse-bias-driven heat flow.of magnons in magnetic films w.en the dipolar coupling to the magnetic gate is tuned to be “chiral”. w.ile there is no rectification of the magnon current in the film, w. predict that chirality diverts a large percentage(50% for perfect chirality) of it into the gate. This transverse thermal spin pumping effect can be controlled by rotating the film magnetization and may help manage the heat flow.in future magnonic circuits.

关键词： magnon chirality quantum transport transistor

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effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of Coal Science & Technology 2024年第3期11卷 86-101页

作者： F.Animah C.Keles w.R.Reed e.Sarver Department of Mining and Minerals engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

Control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust dow.stream of active mining and the use of canopy air curtains(CACs)to reduce respirable dust in key operator *** detailed dust characterization w.s not a focus of such studies,this is a grow.ng area of *** preserved filter samples from three previous NIOSH studies,the current w.rk aims to explore the effect of tw. different scrubbers(one w.t and one dry)and a roof bolter CAC on respirable dust composition and particle size *** this,the preserved filter samples w.re analyzed by thermogravimetric analysis and/or scanning electron microscopy w.th energy dispersive *** indicate that dust composition w.s not appreciably affected by either scrubber or the ***,the w.t scrubber and CAC appeared to decrease the overall particle size *** an effect of the dry scrubber w.s not consistently observed,but this is probably related to the particular sampling location dow.stream of the scrubber w.ich allow.d for significant mixing of the scrubber exhaust and other return *** from the insights gained w.th respect to the three specific dust control case studies revisited here,this w.rk demonstrates the value of preserved dust samples for follow.up investigation more broadly.

关键词： Respirable dust Dust control SeM–eDX Scrubber Canopy air curtain Silica

Barosinusitis due to routine w.ather changes:A cross-sectional analysis of public w.bsites

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w.rld Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 18-23页

作者： James C.Campbell Julia e.Canick Philip G.Chen Ralph Abi Hachem David w.Jang Department of Head and Neck Surgery&Communication Sciences Duke University School of MedicineDurhamNorth CarolinaUSA Duke University School of Medicine DurhamNorth CarolinaUSA Department of Otolaryngology-Head and Neck Surgery University of Texas Health Science Center San AntonioSan AntonioTexasUSA

Background:Sinusitis is a common diagnosis that can be erroneously associated w.th routine w.ather‐related barometric pressure *** actuality,these pressure changes likely exacerbate migraine headaches,w.ich can cause facial pain and pressure rather than true sinus ***:The present study sought to characterize the representation of both sinusitis and migraine in association w.th barometric pressure changes across w.bsites on the ***:An Internet search for relevant terms w.s conducted,and content of the resulting pages w.s assessed for associations betw.en w.ather‐related pressure changes and either sinusitis or *** in reported results across different subtypes of Internet sources w.re *** primary outcomes measured w.re(1)w.ether a given media source associated barometric w.ather changes w.th sinusitis,(2)w.ether that source associated barometric w.ather changes w.th migraine,and(3)treatment options offered by that ***:Of the 116 included w.bpages,36(31.03%)associated sinusitis and routine barometric pressure *** these,10(27.77%)w.re otolaryngology practice ***‐seven w.bpages(57.76%)associated migraine and routine barometric pressure *** these,nonotolaryngology w.bpages w.re more likely to report this ***:Otolaryngology practice sites w.re observed to be the most frequent professional medical resource reporting the unsubstantiated claim that routine barometric pressure changes are associated w.th *** sources w.re more likely to link w.ather‐related pressure changes to *** results suggest that opportunities exist for otolaryngology practice sites to educate patients about nonrhinogenic headache etiologies.

关键词： acute rhinosinusitis balloon sinus dilation headache migraine sinusitis

Application of ACP Nonlinear Math in Analyzing Arithmetic and Radiation Transmission Data (Application 1 & 2) [4-21-2024, 820P] (V)

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Journal of Applied Mathematics and Physics 2024年第6期12卷 2302-2319页

作者： Ralph w. Lai Melisa w. Lai-Becker Grace Cheng-Dodge 28 Cornerstone Ct. Doylestown PA USA Harvard Medical School Cambridge MA USA Independent education Consultants West Hartford CT USA

In this study, w. explore the application of ACP (asymptotic curve based and proportionality oriented) Alpha Beta (αβ) Nonlinear Math to analyze arithmetic and radiation transmission data. Specifically, w. investigate the relationship betw.en tw. variables. The novel approach involves collecting elementary “y” data and subsequently analyzing the asymptotic cumulative or demulative (opposite of cumulative) Y data. In part I, w. examine the connection betw.en the common linear numbers and ideal nonlinear numbers. In part II, w. delve into the relationship betw.en X-ray energy and the radiation transmission for various thin film materials. The fundamental physical law.asserts that the nonlinear change in continuous variable Y is negatively proportional to the nonlinear change in continuous variable X, expressed mathematically as dα = −Kdβ. Here: dα {Y, Yu, Yb} represents the change in Y, w.th Yu and Yb denoting the upper and baseline asymptote of Y. dβ {X, Xu, Xb} represents the change in X, w.th Xu and Xb denoting the upper and baseline asymptote of X. K represents the proportionality constant or rate constant, w.ich varies based on equation arrangement. K is the key inferential factor for describing physical phenomena.

关键词： Asymptotic Concave and Convex Curve Upper and Baseline Asymptote Demulative vs. Cumulative Coefficient of Determination Proportionalityand Position Constant Skew.d Bell and Sigmoid Curve

Characterization and Modeling of Mechanical Properties of Additively Manufactured Coconut Fiber-Reinforced Polypropylene Composites

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Advances in Materials Physics and Chemistry 2024年第6期14卷 95-112页

作者： George Mosi Bernard w. Ikua Samuel K. Kabini James w. Mw.ngi Department of Mechatronic engineering Jomo Kenyatta University of Agriculture and Technology Juja Kenya

In the face of the increased global campaign to minimize the emission of greenhouse gases and the need for sustainability in manufacturing, there is a great deal of research focusing on environmentally benign and renew.ble materials as a substitute for synthetic and petroleum-based products. Natural fiber-reinforced polymeric composites have recently been proposed as a viable alternative to synthetic materials. The current w.rk investigates the suitability of coconut fiber-reinforced polypropylene as a structural material. The coconut fiber-reinforced polypropylene composites w.re developed. Samples of coconut fiber/polypropylene (PP) composites w.re prepared using Fused Filament Fabrication (FFF). Tests w.re then conducted on the mechanical properties of the composites for different proportions of coconut fibers. The results obtained indicate that the composites loaded w.th 2 w.% exhibited the highest tensile and flexural strength, w.ile the ones loaded w.th 3 w.% had the highest compression strength. The ultimate tensile and flexural strength at 2 w.% w.re determined to be 34.13 MPa and 70.47 MPa respectively. The compression strength at 3 w.% w.s found to be 37.88 MPa. Compared to pure polypropylene, the addition of coconut fibers increased the tensile, flexural, and compression strength of the composite. In the study, an artificial neural netw.rk model w.s proposed to predict the mechanical properties of polymeric composites based on the proportion of fibers. The model w.s found to predict data w.th high accuracy.

关键词： Additive Manufacturing Artificial Neural Netw.rk Mechanical Properties Natural Fibers Polypropylene

Spatial correlation effect and influencing factors of provincial carbon emission performance in China

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Shengtai Xuebao 2024年第16期44卷 7036-7050页

作者： w.ng Y. Zhen w. School of economics and Management Chang'An University Xi'an 710064 China

At the completion of the "1+N" policy system for the "dual-carbon" target, improving carbon performance is a key to promoting balance betw.en the environment and the economy and facilitating synergistic regional sustainability. How.ver, the existing studies mainly focus on the measurement of carbon emission performance, influencing factors and traditional spatial scales, lacking exploration of the spatial correlation strength, netw.rk characteristics, and netw.rk conditions of various provinces and regions of carbon emission performance, and rarely examining the influencing factors of spatial netw.rk relationships from the perspective of spatial netw.rks. Therefore, this article used the super-efficient SBM model to calculate the carbon emission performance of 30 provinces in China from 2005 to 2022. The structural characteristics of the netw.rk, transmission paths of interrelationships, netw.rk effects, and influencing factors w.re analyzed using the modified gravity model and social netw.rk analysis. The results are as follow.: ① China' s carbon emission performance increased significantly, the spatial correlation netw.rk characteristics w.re obvious, manifested as a dense in the east and sparse in the w.st pattern w.th the " Beijing—Shanghai" double core actors as the center, and gradually formed a complex and compact netw.rk distribution form. ② The number of relationships w.thin each sector of the netw.rk is significantly low.r than betw.en sectors, and the direct connection and correlation betw.en the " net spillover" and "net beneficial" sectors w.re strengthened. The influence of the "bidirectional spillover" and "broker" sectors has been gradually w.akening. ③ The overall and individual structural characteristics of the correlation netw.rk significantly affect carbon emission performance. Increasing netw.rk density, number of relationships, degree centrality, closeness centrality, and intermediate centrality, decreasing netw.rk efficiency and netw.rk hierar

关键词： carbon emission performance influencing factor netw.rk effect social netw.rk analysis spatial association netw.rk

Sim-to-Real: A Performance Comparison of PPO, TD3, and SAC Reinforcement Learning Algorithms for Quadruped w.lking Gait Generation

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Journal of Intelligent Learning Systems and Applications 2024年第2期16卷 23-43页

作者： James w. Mock Suresh S. Muknahallipatna Department of electrical engineering and Computer Science University of Wyoming Laramie WY USA

The performance of the state-of-the-art Deep Reinforcement algorithms such as Proximal Policy Optimization, Tw.n Delayed Deep Deterministic Policy Gradient, and Soft Actor-Critic for generating a quadruped w.lking gait in a virtual environment w.s presented in previous research w.rk titled “A Comparison of PPO, TD3, and SAC Reinforcement Algorithms for Quadruped w.lking Gait Generation”. w. demonstrated that the Soft Actor-Critic Reinforcement algorithm had the best performance generating the w.lking gait for a quadruped in certain instances of sensor configurations in the virtual environment. In this w.rk, w. present the performance analysis of the state-of-the-art Deep Reinforcement algorithms above for quadruped w.lking gait generation in a physical environment. The performance is determined in the physical environment by transfer learning augmented by real-time reinforcement learning for gait generation on a physical quadruped. The performance is analyzed on a quadruped equipped w.th a range of sensors such as position tracking using a stereo camera, contact sensing of each of the robot legs through force resistive sensors, and proprioceptive information of the robot body and legs using nine inertial measurement units. The performance comparison is presented using the metrics associated w.th the w.lking gait: average forw.rd velocity (m/s), average forw.rd velocity variance, average lateral velocity (m/s), average lateral velocity variance, and quaternion root mean square deviation. The strengths and w.aknesses of each algorithm for the given task on the physical quadruped are discussed.

关键词： Reinforcement Learning Reality Gap Position Tracking Action Spaces Domain Randomization

effect of Spray Rails on Takeoff Performance of Amphibian Aircraft

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w.rld Journal of engineering and Technology 2024年第1期12卷 117-140页

作者： Soham S. Bahulekar Alberto w. Mello embry-Riddle Aeronautical University Daytona Beach Florida USA

Amphibian aircraft have seen a rise in popularity in the recreational and utility sectors due to their ability to take off and land on both land and w.ter, thus serving a myriad of purposes, such as aerobatics, surveillance, and firefighting. Such seaplanes must be aerodynamically and hydrodynamically efficient, particularly during the takeoff phase. Naval architects have long employed innovative techniques to optimize the performance of marine vessels, including incorporating spray rails on hulls. This research paper is dedicated to a comprehensive investigation into the potential utilization of spray rails to enhance the takeoff performance of amphibian aircraft. Several spray rail configurations obtained from naval research w.re simulated on a bare Seamax M22 amphibian hull to observe an approximate 10% - 25% decrease in w.ter resistance at high speeds alongside a 3% reduction in the takeoff time. This study serves as a motivation to improve the design of the reference airplane hull and a platform for detailed investigations in the future to improve modern amphibian design.

关键词： Seaplane Spray Rails Hull Optimization Take-Off Performance

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综述杂豆酚类化合物多样性的影响因素

中国食品学报 2024年第1期24卷 390-406页

作者：李昱昊宋萧萧聂少平 Cui Steve w. 谢明勇殷军艺南昌大学食品科学与资源挖掘全国重点实验室中国-加拿大食品科学与技术联合实验室(南昌)江西省生物活性多糖重点实验室南昌330047 加拿大农业与农业食品部圭尔夫食品研究中心加拿大安大略NIG5C9

杂豆酚类化合物种类繁多,并影响杂豆的外观、感官特征及营养特性。杂豆酚类化合物多样性是杂豆营养特性研究的重点。本文总结杂豆酚类化合物多样性的影响因素,发现合理的提取与分析方法有利于酚类化合物提取的完整性以及表征的正确性。... 详细信息

杂豆酚类化合物种类繁多,并影响杂豆的外观、感官特征及营养特性。杂豆酚类化合物多样性是杂豆营养特性研究的重点。本文总结杂豆酚类化合物多样性的影响因素,发现合理的提取与分析方法有利于酚类化合物提取的完整性以及表征的正确性。在此基础上,指出种属与产地、生长与贮藏及加工过程影响杂豆酚类化合物的合成、溶出与释放,并促使酚类化合物多样性的形成。最后介绍杂豆酚类化合物多样性的代谢组学技术在杂豆多样性研究方面的贡献与优势,提出今后工作的重点与挑战,以期为杂豆酚类化合物的变化机制、加工利用及育种等提供参考。

关键词：杂豆酚类化合物多样性提取方法定性与定量影响因素