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A coupled legendre-laguerre polynomial method with analytical integration for the Rayleigh waves in a quasicrystal layered half-space with an imperfect interface

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1539-1556页

作者： Bo ZHANG Honghang TU Weiqiu CHEN Jiangong YU l.ElMAIMOUNI School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000Henan ProvinceChina Henan International Joint laboratory of Advanced Electronic Packaging Materials Precision Forming Henan Polytechnic UniversityJiaozuo 454000Henan ProvinceChina Department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China Polydisciplinary Faculty of Ouarzazate Ibnou Zohr UniversityOuarzazate 45000Morocco

The laguerre polynomial method has been successfully used to investigate the dynamic responses of a ***,it fails to obtain the correct stress at the interfaces in a layered half-space,especially when there are significant differences in material ***,a coupled legendre-laguerre polynomial method with analytical integration is *** Rayleigh waves in a one-dimensional(1D)hexagonal quasicrystal(QC)layered half-space with an imperfect interface are *** correctness is validated by comparison with available *** computation efficiency is *** dispersion curves of the phase velocity,displacement distributions,and stress distributions are *** effects of the phonon-phason coupling and imperfect interface coefficients on the wave characteristics are *** novel findings reveal that the proposed method is highly efficient for addressing the Rayleigh waves in a QC layered *** can save over 99%of the computation *** method can be expanded to investigate waves in various layered half-spaces,including earth-layered media and surface acoustic wave(SAW)devices.

关键词： coupled legendre-laguerre polynomial method analytical integration Rayleigh wave quasicrystal(QC)layered half-space imperfect interface

Deep bed filtration model for cake filtration and erosion

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： l.I.KUZMINA Y.V.OSIPOV A.R.PESTEREV Department of Applied Mathematics HSE UniversityMoscow 101000Russia Department of Computer Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. In the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analytical solution concentration front

新时代贵州乡村文化价值构建促进乡村振兴研究

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现代农业研究 2024年第2期30卷 56-58页

作者：冯大霓遵义师范学院贵州遵义563000

实现乡村振兴,发展农村产业、提高农民生活水平,就要在新时代条件下通过构建价值体系复兴乡村文明,为此有必要通过相应的调研,从发展的历史脉络中系统地把握乡村文明“繁荣—衰落—复兴”的发展趋势及其“传统到新生代的”建构的规律。... 详细信息

实现乡村振兴,发展农村产业、提高农民生活水平,就要在新时代条件下通过构建价值体系复兴乡村文明,为此有必要通过相应的调研,从发展的历史脉络中系统地把握乡村文明“繁荣—衰落—复兴”的发展趋势及其“传统到新生代的”建构的规律。乡村有广阔的文化培养土壤,乡村文化价值的挖掘与发行对于激发乡村振兴的农民主体性能形成一股不可小觑的动力。贵州富含丰富的文化资源,乡村文化是贵州经典的文化资源,以农村广阔天地的文化为背景,以乡村核心的文明为抓手,做到以文化价值聚合主体力量,以经济发展为再生动力助力贵州发展。

关键词：文化构建乡村振兴红色文化价值体系

Effect of relative humidity on the desulfurization performance of calcium-based desulfurizer

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Journal of Environmental Sciences 2024年第4期138卷 179-188页

作者： Juan lǖ Yu Fu Haiyan Yu HuanWang Zhe Wang Haiyan Chen School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China Guangyuan Emergency Management bureau Guangyuan 628000China

low desulfurization efficiency impedes the wide application of dry desulfurization technology,which is a low-cost and simple process,and one significant solution is the development and manufacture of high-performance *** this study,firstly,a steam jet mill was used to digest quicklime;then,we utilized numerical simulation to study the flow field distribution and analyze the driving factors of quicklime digestion;and lastly,the desulfurization performance of the desulfurizer was evaluated under different relative *** results show that the desulfurizer prepared via the steam jet mill had better apparent activity than traditional ***,the entire jet flow field of the steam jet mill is in a supersonic and highly turbulent flow state,with high crushing intensity and good particle acceleration *** contact with the nascent surface maximizes the formation of slaked *** experiments demonstrated that the operating time with 100%desulfurization efficiency and the“break-through”time for the desulfurizer prepared via the steam jet mill is longer than that of traditional desulfurizers,and has significant advantages,especially at low flue gas relative *** with traditional desulfurizers,the desulfurizer prepared via steam jet mill expands the range of acceptable flue gas temperature,and the failure temperature is 1.625 times that of traditional *** work breaks through the technical bottleneck of low dry desulfurization efficiency,which is an important step in pushing forward the application of dry desulfurization.

关键词： Dry desulfurization Relative humidity Desulfurization efficiency High-efficiency desulfurizer Quicklime digestion

Control Policy learning Design for Vehicle Urban Positioning via BeiDou Navigation

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Journal of Systems Science & Complexity 2024年第1期37卷 114-135页

作者： QIN Yahang ZHANG Chengye CHEN Ci XIE Shengli lEWIS Frank l School of Automation Guangdong University of TechnologyGuangzhou 510006China Guangdong Key laboratory of IoT Information Technology Guangzhou 510006China. Center for Intelligent Batch Manufacturing Based on IoT Technology Key laboratory of Intelligent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong-HongKong-Macao Joint laboratory for Smart Discrete Manufacturing Guangzhou 510006China Key laboratory of Intelligent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China. UTA Research Institute The University of Texas at ArlingtonFort WorthTX 76019USA

This paper presents a learning-based control policy design for point-to-point vehicle positioning in the urban environment via BeiDou *** navigating in urban canyons,the multipath effect is a kind of interference that causes the navigation signal to drift and thus imposes severe impacts on vehicle localization due to the reflection and diffraction of the BeiDou ***,the authors formulated the navigation control system with unknown vehicle dynamics into an optimal control-seeking problem through a linear discrete-time system,and the point-to-point localization control is modeled and handled by leveraging off-policy reinforcement learning for feedback *** proposed learning-based design guarantees optimality with prescribed performance and also stabilizes the closed-loop navigation system,without the full knowledge of the vehicle *** is seen that the proposed method can withstand the impact of the multipath effect while satisfying the prescribed convergence rate.A case study demonstrates that the proposed algorithms effectively drive the vehicle to a desired setpoint under the multipath effect introduced by actual experiments of BeiDou navigation in the urban environment.

关键词： BeiDou navigation multipath effect prescribed convergence rate reinforcement learning urban localization.

Two-Stream Approximation to the Radiative Transfer Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： F.Momo TEMGOUA l.Akana NGUIMDO DNJOMO Environmental Energy Technologies laboratory(EETl) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the development of the phase function and the intensity into a third-order series of legendre polynomials. This new approach, which adds one more term in the expression of the intensity and the phase function, allows in the conditions of a plane parallel atmosphere a new mathematical formulation of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta Function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion function of the proposed New Method using the fundamental definition of two-stream approximation(F-TSA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angle μ 0, but tends to deviate from the Disort method with the zenith angle, especially for high values of optical thickness. In spite of this divergence in reflectance for high values of optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained for most cases of optical thickness in this study. An analysis of the legendre polynomial series for simple functions shows that the high precision is due to the fact that the approximated functions ameliorate the accuracy when the order of approximation increases, although it has been proven that there is a limit order depending on the function from which the precision is lost. This observation indicates that increasing the order of app

关键词： Radiative Transfer Equation two-stream method legendre polynomial optical thickness moments of specific intensity conversion function transmittance reflectance

Improved Reall-Santos method for AdS black holes in general 4-derivative gravities

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 74-86页

作者： Peng-Ju Hu liang Ma Hong lü Yi Pang Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Peng Huanwu Center for Fundamental Theory Hefei 230026China

For asymptotically flat black holes,Reall-Santos method is a convenient tool to compute leading higher derivative corrections to the thermodynamic quantities without actually solving the modified field ***,there are subtleties in its generalization to asymptotically AdS black holes with general higher derivative *** of all,it is necessary to know all the higher derivative holographic counterterms and the surface terms implementing the variational principle and subtracting the *** then needs to solve for the modified AdS radius and rescale the time coordinate in an appropriate way such that the induced metric on the conformal boundary of AdS black hole is not *** observe that Reall-Santos method can be directly applied to a particular 4-derivative gravity model,known as the Einstein-Weyl gravity,which does not modify the AdS radius and requires only the Gibbons-Hawking-York term and holographic counterterms for the 2-derivative *** thus suggest that to compute the thermodynamic quantities of AdS black holes in general 4-derivative theories of gravity,one simply needs to transform it to a Einstein-Weyl gravity with identical thermodynamic variables by appropriate field *** explicitly verify this proposal with spherically-symmetric and static charged black holes in Einstein-Maxwell theory extended with generic 4-derivative interactions.

关键词： black holes thermodynamics higher-derivative corrections effective theories higher dimensional black holes quantum gravity

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Zassenhaus lemma,Schreier Refinement Theorem,and Jordan–Hölder Theorem for Gyrogroups

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Algebra Colloquium 2024年第2期31卷 323-332页

作者： Prathomjit Khachorncharoenkul Rasimate Maungchang Teerapong Suksumran l.A.Bokut School of Science Walailak UniversityNakhon Si Thammarat 80160Thailand Department of Mathematics Faculty of ScienceChiang Mai University Chiang Mai 50200Thailand 不详

In this article,we extend the Zassenhaus lemma(also called the butterfly lemma)and the Schreier refinement theorem to the case of *** addition,we use these results to prove the Jordan–Hölder theorem for gyrogroups as... 详细信息

关键词： Zassenhaus lemma Schreier refinement theoremg yrogroup subgyrogroup diagram normal subgyrogroup

Simultaneous removal of critical rare earth elements and chalcogen oxyanions by anaerobic granular sludge

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Rare Metals 2024年第9期43卷 4595-4611页

作者： Chiara Belloni Mohanakrishnan logan Stefano Papirio Piet N.l.lens University of Galway Department of Civil Architectural and Environmental EngineeringUniversity of Naples Federico II

Conventional mining of economically and strategically important critical rare earth elements(REEs)(such as neodymium, lanthanum and dysprosium), and chalcogens(such as selenium and tellurium) are associated with a huge economic and environmental cost. Therefore,the need to recover REEs as well as chalcogens from different waste streams including wastewaters is becoming urgent. Batch assays on synthetic chalcogen/REE-laden wastewater showed that the presence of REEs significantly improved the tellurite removal rate(> 80%) and enhanced selenate removal by 66% ± 10%. Three 3.9 l continuous upflow anaerobic granular sludge bed(UASB) reactors were operated at a hydraulic retention time of 24 h and30 °C. Selenate reduction was achieved with a removal efficiency of ～ 98% with an influent p H of 4.0 for more than 28 days. The effect of REEs on tellurite removal in the UASB bioreactor could not be clearly established since a soluble tellurium removal efficiency of more than 98%was observed already before the addition of REEs at elevated tellurite concentrations. The complete REE removal in both batch assays and UASB reactors at higher pH (7.0 ± 0.5) was attributed to precipitation, whereas chalcogen oxyanions removal was due to microbial reduction. However, at acidic p H, biosorption was responsible for REE's removal, and the Se-enriched sludge exhibited a superior REE's removal efficiency than the non-enriched and Te-enriched sludge.

关键词： Adsorption Bioreduction Rare earth elements Selenium Tellurium