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Digital communications and Networks 2024年第1期10卷 25-37页

作者： Daosen Zhai Huan Li Xiao Tang Ruonan Zhang Haotong cao School of Electronics and Information Northwestern Polytechnical UniversityXian710072China State Key Laboratory of Integrated Services Networks Xidian UniversityXian710071China Department of computing Hong Kong Polytechnic UniversityHong Kong SARChina

Unbalanced traffic distribution in cellular networks results in congestion and degrades spectrum *** tackle this problem,we propose an Unmanned Aerial Vehicle(UAV)-assisted wireless network in which the UAV acts as an aerial relay to divert some traffic from the overloaded cell to its adjacent underloaded *** fully exploit its potential,we jointly optimize the UAV position,user association,spectrum allocation,and power allocation to maximize the sum-log-rate of all users in two adjacent *** tackle the complicated joint optimization problem,we first design a genetic-based algorithm to optimize the UAV ***,we simplify the problem by theoretical analysis and devise a low-complexity algorithm according to the branch-and-bound method,so as to obtain the optimal user association and spectrum allocation *** further propose an iterative power allocation algorithm based on the sequential convex approximation *** simulation results indicate that the proposed UAV-assisted wireless network is superior to the terrestrial network in both utility and throughput,and the proposed algorithms can substantially improve the network performance in comparison with the other schemes.

关键词： Load balance Unmanned aerial vehicle Userassociation Resource management

Targeting synaptic pathology in Alzheimer’s disease

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Zoological Research 2024年第4期45卷 875-876页

作者： Jing cao Yun-Wu Zhang Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research Institute of NeuroscienceSchool of MedicineXiamen UniversityXiamenFujian 361102China

Alzheimer’s disease(AD)is a neurodegenerative disorder characterized by memory and cognitive *** two primary pathological hallmarks of AD include the accumulation ofβ-amyloid(Aβ)plaques and formation of neurofibrillary tangles(NFTs)composed predominantly of hyperphosphorylated tau protein(Zhang et al.,2023).Moreover,synaptic dysfunction is considered another crucial factor in AD pathogenesis and is closely associated with cognitive ***,synaptic damage,loss,and dysfunction manifest earlier than the pathological features of Aβplaques and NFTs(Knopman et al.,2021).Therefore,understanding the mechanisms underlying synaptic dysfunction in AD is vital for providing insights into disease mechanisms and developing novel therapeutic strategies.

关键词： Alzheimer Aβ tau

Research on an innovative structure of an open-ribbed steel-ultra-high performance concrete composite bridge deck

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Frontiers of Structural and civil Engineering 2024年第5期18卷 716-730页

作者： Xudong SHAO Xuan SUN Deqiang ZOU Junhui cao chuanqi YANG School of civil Engineering Hunan UniversityKey Laboratory for Wind and Bridge Engineering of Hunan ProvinceChangsha 410082China china construction Fifth Engineering Division co. Ltd.Changsha 410004China

To completely solve the problem of fatigue cracking issue of orthotropic steel bridge decks(OSDs),the authors proposed a steel–ultra-high performance concrete(UHPc)lightweight composite deck(LWcD)with closed ribs in *** on the successful application of that LWcD,an adaptation incorporating an innovative composite deck structure,i.e.,the hot-rolled section steel–UHPc composite deck with open ribs(SSD)is proposed in this paper,aiming to simplify the fabrication process as well as to reduce the cost of *** on a long-span cable-stayed bridge,a design scheme is proposed and is compared with the conventional OSD ***,a finite element(FE)calculation is conducted to reflect both the global and local behavior of the SSD scheme,and it is found that the peaked stresses in the SSD components are less than the corresponding allowable values.A static test is performed for an SSD strip specimen to understand the anti-cracking behavior of the UHPc layer under negative bending *** static test results indicate that the UHPc layer exhibited a satisfactory tensile toughness,the UHPc tensile strength obtained from the test is 1.8 times the calculated stress by the FE model of the real *** addition,the fatigue stresses of typical fatigue-prone details in the SSD are calculated and evaluated,and the influences of key design parameters on the fatigue performance of the SSD are *** to the fatigue results,the peaked stress ranges for all of the 10 fatigue-prone details are within the corresponding constant amplitude fatigue *** a fatigue test is carried out for another SSD strip specimen to explore the fatigue behavior of the fillet weld between the longitudinal and transverse *** specimen failed at the fillet weld after equivalent 47.5 million cycles of loading under the design fatigue stress range,indicating that the fatigue performance of the SSD could meet the fatigue design *** calculations and experim

关键词： steel-ultra-high performance concrete composite deck open rib strip model test static and fatigue performance orthotropic steel deck

Variability Analysis for a Two-station Queueing Network in Heavy Traffic with Arrival Processes Driven by Queues

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 445-466页

作者： Jian cao Yong-jiang GUO Kai-ming YANG School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

The law of the iterated logarithm(LIL)for the performance measures of a two-station queueing network with arrivals modulated by independent queues is developed by a strong approximation *** convenience,two arrival processes modulated by queues comprise the external system,all others are belong to the internal *** is well known that the exogenous arrival has a great influence on the asymptotic variability of performance measures in *** the considered queueing network in heavy traffic,we get all the LILs for the queue length,workload,busy time,idle time and departure processes,and present them by some simple functions of the primitive *** LILs tell us some interesting insights,such as,the LILs of busy and idle times are zero and they reflect a small variability around their fluid approximations,the LIL of departure has nothing to do with the arrival process,both of the two phenomena well explain the service station’s situation of being busy all the *** external system shows us a distinguishing effect on the performance measures:an underloaded(overloaded,critically loaded)external system affects the internal system through its arrival(departure,arrival and departure together).In addition,we also get the strong approximation of the network as an auxiliary result.

关键词： two-station queueing network the law of the iterated logarithm(LIL) strong approximation fluid approximation

Ultrasound sensing with optical microcavities

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Light(Science & Applications) 2024年第8期13卷 1487-1511页

作者： Xuening cao Hao Yang Zu-Lei Wu Bei-Bei Li Beijing National Laboratory for condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of chinese Academy of Sciences Beijing 100049China School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China Songshan Lake Materials Laboratory Dongguan 523808 GuangdongChina

Ultrasound sensors play an important role in biomedical imaging,industrial nondestructive inspection,*** ultrasound sensors that use piezoelectric transducers face limitations in sensitivity and spatial resolution when miniaturized,with typical sizes at the millimeter to centimeter *** overcome these challenges,optical ultrasound sensors have emerged as a promising alternative,offering both high sensitivity and spatial *** particular,ultrasound sensors utilizing high-quality factor(Q)optical microcavities have achieved unprecedented performance in terms of sensitivity and bandwidth,while also enabling mass production on silicon *** this review,we focus on recent advances in ultrasound sensing applications using three types of optical microcavities:Fabry-Perot cavities,π-phase-shifted Bragg gratings,and whispering gallery mode *** provide an overview of the ultrasound sensing mechanisms employed by these microcavities and discuss the key parameters for optimizing ultrasound ***,we survey recent advances in ultrasound sensing using these microcavity-based approaches,highlighting their applications in diverse detection scenarios,such as photoacoustic imaging,ranging,and particle *** goal of this review is to provide a comprehensive understanding of the latest advances in ultrasound sensing with optical microcavities and their potential for future development in high-performance ultrasound imaging and sensing technologies.

关键词： optical millimeter offering

co-incorporating green manure and crop straw increases crop productivity and improves soil quality with low greenhouse-gas emissions in a crop rotation

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The crop Journal 2024年第4期12卷 1233-1241页

作者： Na Zhao Xiquan Wang Jun Ma Xiaohong Li Jufeng cao Jie Zhou Linmei Wu Peiyi Zhao Weidong cao Bayannur Academy of Agricultural and Animal Sciences Linhe 015400Inner MongoliaChina college of Agronomy Inner Mongolia Agricultural UniversityHohhot 010019Inner MongoliaChina college of Agriculture Nanjing Agricultural UniversityNanjing 210095JiangsuChina Inner Mongolia Academy of Agricultural&Animal Husbandry Sciences Hohhot 010031Inner MongoliaChina State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern china/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China

In a nine-year field experiment in a wheat-maize-sunflower cropping system in Hetao Irrigation Area,Inner Mongolia,china,organic amendments applied as straw,manure,green manure,and the combination of green manure and straw increased wheat and maize yield,soil aggregate stability,and soil microbial activity in comparison with chemical fertilizer,without changing greenhouse gas emission intensity.

关键词： Green manure Straw Manure Soil organic carbon Soil quality crop production Diversified cropping

Energy modeling and optimization of building condenser water systems with all-variable speed pumps and tower fans:A case study

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Building Simulation 2024年第7期17卷 1085-1111页

作者： Yong cao chuang Wang Sheng Wang Xiao Fu Xinguo Ming School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Air-conditioning Equipment and System Energy conservation Zhuhai 519070China GREE Electric Appliances Inc.of ZhuhaiZhuhai 519070China School of Environment and Energy Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China Beijing Advanced Innovation centerfor Future Urban Design Beijing University of Civil Engineering and ArchitectureBeijing 100044China

The emergence of building condenser water systems with all-variable speed pumps and tower fans allows for increased efficiency and flexibility of chiller plants in partial load operation but also increases the control complexity of condenser water *** study aims to develop an integrated modeling technique for evaluating and optimizing the energy performance of such a condenser water *** proposed system model is based on the semi-physical semi-empirical chiller,pump,and cooling tower models,with capabilities of fully considering the hydraulic and thermal interactions in the condenser water loop,being solved analytically and much faster than iterative solvers and supporting the explicit optimization of the pump and tower fan frequency.A mathematical approach,based on the system model and constrained optimization technique,is subsequently established to evaluate the energy performance of a typical dual setpoint-based variable speed strategy and find its energy-saving potential and most efficient operation by jointly optimizing pumps and tower *** all-variable speed chiller plant from Wuhan,china,is used for a case study to validate the system model’s accuracy and explore its *** results showed that the system model can accurately simulate the condenser water system’s performance under various operating *** optimizing the frequencies of pumps and tower fans,the total system energy consumption can be reduced by 12%–13%compared to the fixed dual setpoint-based strategy with range and approach setpoints of 4℃and 2℃.In contrast,the energy-saving potential of optimizing the cooling tower sequencing is insignificant.A simple joint speed control method for optimizing the pumps and tower fans emerged,i.e.,the optimal pump and fan frequency are linearly correlated(if both are non-extremes)and depend on the chiller part load ratio only,irrespective of the ambient wet-bulb temperature and chilled water supply *** was also foun

关键词： all-variable speed chiller plant model-based optimization hydraulic and thermal coupling analytical solution dual setpoint-based variable speed control optimal joint speed control

Ionic Liquid-Enhanced Assembly of Nanomaterials for Highly Stable Flexible Transparent Electrodes

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Nano-Micro Letters 2024年第7期16卷 441-455页

作者： Jianmin Yang Li chang Xiqi Zhang Ziquan cao Lei Jiang Key Laboratory of Bio-Inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China University of chinese Academy of Sciences Beijing 100049People’s Republic of China college of chemistry and chemical Engineering Chongqing University of TechnologyChongqing 400054People’s Republic of China Binzhou Institute of Technology Binzhou 256600People’s Republic of China Nanomics Biotechnology co. Ltd.HangzhouPeople’s Republic of China

The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological ***,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the creation of hierarchical structures with distinctive func-tionalities,remains a formidable ***,we present a method for nanomaterial assembly enhanced by ionic liquids,which enables the fabrication of highly stable,flexible,and transparent electrodes featuring an organized layered *** utilization of hydrophobic and non-volatile ionic liquids facilitates the production of stable interfaces with water,effectively preventing the sedimentation of 1D/2D nanomaterials assembled at the ***,the interfacially assembled nanomaterial monolayer exhibits an alternate self-climbing behavior,enabling layer-by-layer transfer and the formation of a well-ordered MXene-wrapped silver nanowire network *** resulting composite film not only demonstrates exceptional photoelectric performance with a sheet resistance of 9.4Ωsq^(-1) and 93%transmittance,but also showcases remarkable environmental stability and mechanical *** noteworthy is its application in transparent electromagnetic interference shielding materials and triboelectric nanogenerator *** research introduces an innovative approach to manufacture and tailor functional devices based on ordered nanomaterials.

关键词： Ionic liquids Assembly Silver nanowires MXene nanosheets Flexible transparent electrodes

A Hybrid Air Quality Prediction Model Based on Empirical Mode Decomposition

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Tsinghua Science and Technology 2024年第1期29卷 99-111页

作者： Yuxuan cao Difei Zhang Shaoqi Ding Weiyi Zhong chao Yan School of computer Science Qufu Normal UniversityRizhao 276826China School of Mathematical Sciences Qufu Normal UniversityQufu 273165China School of computer Science Qufu Normal UniversityRizhao 270826China college of Economic and Management Shandong University of Science and TechnologyQingdao 250307China

Air pollution is a severe environmental problem in urban *** air quality prediction can help governments and individuals make proper decisions to cope with potential air *** a classic time series forecasting model,the AutoRegressive Integrated Moving Average(ARIMA)has been widely adopted in air quality ***,because of the volatility of air quality and the lack of additional context information,i.e.,the spatial relationships among monitor stations,traditional ARIMA models suffer from unstable prediction *** some deep networks can achieve higher accuracy,a mass of training data,heavy computing,and time cost are *** this paper,we propose a hybrid model to simultaneously predict seven air pollution indicators from multiple monitoring *** proposed model consists of three components:(1)an extended ARIMA to predict matrix series of multiple air quality indicators from several adjacent monitoring stations;(2)the Empirical Mode Decomposition(EMD)to decompose the air quality time series data into multiple smooth sub-series;and(3)the truncated Singular Value Decomposition(SvD)to compress and denoise the expanded *** results on the public dataset show that our proposed model outperforms the state-of-art air quality forecasting models in both accuracy and time cost.

关键词： air quality prediction Empirical Mode Decomposition(EMD) Singular Value Decomposition(SVD) AutoRegressive Integrated Moving Average(ARIMA)

Non-volatile dynamically switchable color display via chalcogenide stepwise cavity resonators

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Opto-Electronic Advances 2024年第1期7卷 16-27页

作者： Kuan Liu Zhenyuan Lin Bing Han Minghui Hong Tun cao School of Optoelectronic Engineering and Instrumentation Science Dalian University of TechnologyDalian 116024China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361102China Institute of Laser Engineering Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

High-resolution multi-color printing relies upon pixelated optical nanostructures,which is crucial to promote color display by producing nonbleaching colors,yet requires simplicity in fabrication and dynamic *** trisulfide(Sb_(2)S_(3))is a newly rising chalcogenide material that possesses prompt and significant transition of its optical characteristics in the visible region between amorphous and crystalline phases,which holds the key to color-varying ***,we proposed a dynamically switchable color printing method using Sb_(2)S_(3)-based stepwise pixelated Fabry-Pérot(FP)cavities with various cavity *** device was fabricated by employing a direct laser patterning that is a less timeconsuming,more approachable,and low-cost *** switching the state of Sb_(2)S_(3) between amorphous and crystalline,the multi-color of stepwise pixelated FP cavities can be actively *** color variation is due to the profound change in the refractive index of Sb_(2)S_(3) over the visible spectrum during its phase ***,we directly fabricated sub-50 nm nano-grating on ultrathin Sb_(2)S_(3) laminate via microsphere 800-nm femtosecond laser irradiation in far *** minimum feature size can be further decreased down to~45 nm(λ/17)by varying the thickness of Sb_(2)S_(3) *** switchable Sb_(2)S_(3) photonic devices can take one step toward the next generation of inkless erasable papers or displays and enable information encryption,camouflaging surfaces,anticounterfeiting,***,our work explores the prospects of rapid and rewritable fabrication of periodic structures with nano-scale resolution and can serve as a guideline for further development of chalcogenide-based photonics components.

关键词： tunable color displays Fabry-Pérot cavity resonators color printing chalcogenide materials