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Enhancing force sensing in a squeezed optomechanical system with quantum nondemolition measurement

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Communications in Theoretical Physics 2024年第1期76卷 49-60页

作者： Shi-lei Chao Zi-Hao li Xin-You lü School of Physics Huazhong University of Science and Technology430074 WuhanChina

A theoretical scheme is proposed to enhance the sensitivity of force sensors with quantum nondemolition measurement(QND)in an optomechanical setup assisted by four-tone optical driving and an optical parametric amplifier(OPA).With the help of special drive,the system can be simplified as the typical type of QND for force sensing,so that the backaction noise can be evaded to surpass the standard quantum ***,the added noise can be suppressed owing to the modified optical susceptibility resulting from the *** introducing two oscillators coupling with two charged bodies respectively,the signal can be enhanced with the nonlinearity caused by Coulomb interaction,while the noise presents an exponential ***,considering the homodyne detection effect,the range of system parameters and frequency bands will be *** present investigation may provide a route toward simultaneously evading backaction noise,reducing the mechanical thermal noise,and enhancing the external signal,which can be an alternative design for sensitive devices.

关键词： force sensing optical parametric amplifier quantum non-demolition measurement optomechanical system

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

Weighted Probability Density Estimator with Updated Bandwidths

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Journal of Systems Science & Complexity 2024年第2期37卷 886-906页

作者： WU Yi YU Wei WANG Xuejun PRAKASA RAO B l S School of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000China School of Big Data and Statistics Anhui UniversityHefei 230601China CR Rao Advanced Institute of Mathematics Statistics and Computer ScienceHyderabad 500046India

In this paper,the authors study a class of weighted version of probability density *** is shown that the weighted estimator contains some existing estimators of probability density,no matter they are recursive or *** statistical results including weak consistency,strong consistency,rate of strong consistency,and asymptotic normality are established under some mild ***,the random weighted estimator is also *** numerical simulations and a real data analysis are presented to study the numerical performances of the estimators.

关键词： Asymptotic normality consistency numerical simulation probability density real data analysis updated bandwidths weighted estimator

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 Galway H91 TK33Ireland Department of Civil Architectural and Environmental EngineeringUniversity of Naples Federico II80125 NaplesItaly

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 ***,the need to recover REEs as well as chalcogens from different waste streams including wastewaters is becoming *** 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 and 30℃.Selenate reduction was achieved with a removal efficiency of~98% with an influent p H of 4.0 for more than 28 *** 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 *** 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 ***,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： Rare earth elements Selenium Tellurium Bioreduction Adsorption

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

The flattening of spacetime hierarchy of the N,N-dimethyltryptamine brain state is characterized by harmonic decomposition of spacetime(HADES) framework

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National Science Review 2024年第5期11卷 46-55页

作者： Jakub Vohryzek Joana Cabral Christopher Timmermann Selen Atasoy leor Roseman David J.Nutt Robin l.Carhart-Harris Gustavo Deco Morten l.Kringelbach Centre for Eudaimonia and Human Flourishing Linacre CollegeDepartment of Psychiatry University of Oxford Department of Psychiatry University of Oxford Center for Music in the Brain Aarhus University Center for Brain and Cognition Computational Neuroscience GroupDepartment of Information and Communication TechnologiesUniversitat Pompeu Fabra life and Health Sciences Research Institute School of MedicineUniversity of Minho ICVS/3B's-PT Government Associate laboratory Centre for Psychedelic Research Department of Brain Sciences Imperial College London Departments of Neurology and Psychiatry University of California San Francisco Institució Catalana de la Recerca i Estudis Avan?ats (ICREA) Department of Neuropsychology Max Planck Institute for Human Cognitive and Brain Sciences School of Psychological Sciences Monash University

The human brain is a complex system, whose activity exhibits flexible and continuous reorganization across space and time. The decomposition of whole-brain recordings into harmonic modes has revealed a repertoire of gradient-like activity patterns associated with distinct brain functions. However, the way these activity patterns are expressed over time with their changes in various brain states remains unclear. Here, we investigate healthy participants taking the serotonergic psychedelic N,N-dimethyltryptamine(DMT) with the Harmonic Decomposition of Spacetime(HADES) framework that can characterize how different harmonic modes defined in space are expressed over time. HADES demonstrates significant decreases in contributions across most low-frequency harmonic modes in the DMT-induced brain state. When normalizing the contributions by condition(DMT and non-DMT), we detect a decrease specifically in the second functional harmonic, which represents the uni-to transmodal functional hierarchy of the brain,supporting the leading hypothesis that functional hierarchy is changed in psychedelics. Moreover, HADES'dynamic spacetime measures of fractional occupancy, life time and latent space provide a precise description of the significant changes of the spacetime hierarchical organization of brain activity in the psychedelic state.

关键词： spatio-temporal brain dynamics DMT harmonic modes

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

Feasibility of achieving net-zero energy performance in high-rise buildings using solar energy

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Energy and Built Environment

Energy and Built Environment 2024年第6期5卷 946-956页

作者： Mehrdad Shirinbakhsh l.D.Danny Harvey University of Toronto 100St.George StreetTorontoONM5S 3G3Canada

As part of a broad strategy to reach net-zero greenhouse gas emissions and limit global warming,many countries are requiring all new buildings to have net-zero energy *** requires that on-site energy use not exceed on-site generation of renewable energy(taken here to be solar energy),or equivalently,that the building Energy Use Intensity(EUI,kWh/m^(2)a)not exceed the supply of on-site solar energy(electricity and heat)per m^(2)of floor area per *** this basis,we find that achieving net-zero energy performance in an archetype 40-story square building in 16 different cities of North America requires EUI of 17–24 kWh/m^(2)a using PV panels,and 19–28 kWh/m^(2)a using PVT *** building orientation to a non-square floor shape can improve maximum permitted EUI by up to 50%in PV and 60%in PVT ***,the best-performing residential and commercial buildings have EUIs of 50–75 kWh/m^(2)*** if building heights are limited to 5–10 floors does the available solar energy,and thus the permitted EUI,reach 50–75 kWh/m^(2)***,we recommend that policymakers not require high-rise buildings to be net-zero energy,unless they are prepared to limit building heights to 5–10 floors.

关键词： High-rise net-zero energy buildings Building geometry Building height Solar NZEB

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.