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Online Computation Offloading and Trajectory Scheduling for UAV-Enabled Wireless Powered Mobile Edge Computing

China Communications 2022年第4期19卷 257-273页

作者： Han hu Xiang Zhou Qun Wang rose qingyang hu The Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China The Engineering Research Center of Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjing University of Posts and TelecommunicationsNanjing 210003China The Department of Electrical and Computer Engineering Utah State UniversityLoganUTUSA.

The unmanned aerial vehicle(UAV)-enabled mobile edge computing(MEC) architecture is expected to be a powerful technique to facilitate 5 G and beyond ubiquitous wireless connectivity and diverse vertical applications and services, anytime and anywhere. Wireless power transfer(WPT) is another promising technology to prolong the operation time of low-power wireless devices in the era of Internet of Things(IoT). However, the integration of WPT and UAV-enabled MEC systems is far from being well studied, especially in dynamic environments. In order to tackle this issue, this paper aims to investigate the stochastic computation offloading and trajectory scheduling for the UAV-enabled wireless powered MEC system. A UAV offers both RF wireless power transmission and computation services for IoT devices. Considering the stochastic task arrivals and random channel conditions, a long-term average energyefficiency(EE) minimization problem is *** to non-convexity and the time domain coupling of the variables in the formulated problem, a lowcomplexity online computation offloading and trajectory scheduling algorithm(OCOTSA) is proposed by exploiting Lyapunov optimization. Simulation results verify that there exists a balance between EE and the service delay, and demonstrate that the system EE performance obtained by the proposed scheme outperforms other benchmark schemes.

关键词： energy efficiency mobile edge computing UAV-enabled wireless power transfer trajectorys cheduling

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A Privacy-Preserving Scheme for Location-Based Services in the Internet of Vehicles

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Journal of Communications and Information Networks 2021年第4期6卷 385-395页

作者： Jiaqi huang Yi Qian rose qingyang hu University of Central Missouri 116 W South StWarrensburgMO 64093USA Unviersity of Nebraska-Lincoln 1110 S 67th StOmahaNE 68182USA Utah State University LoganUT 84322USA

Ubiquitous information exchange is achieved among connected vehicles through the increasingly smart *** concept of conventional vehicular ad hoc network is gradually transformed into the Internet of vehicles(IoV).Meanwhile,more and more locationbased services(LBSs)are created to provide convenience for ***,the frequently updated location information sent to the LBS server also puts user location privacy at ***,preserve user location privacy while allowing vehicles to have high-quality LBSs is a critical *** solutions have been proposed in the literature to preserve location ***,most of them cannot provide real-time LBS with accurate location *** this paper,we propose a novel location privacy-preserving scheme,which allows vehicles to send accurate real-time location information to the LBS server while preventing being tracked by *** the proposed scheme,a vehicle utilizes the location information of selected shadow vehicles,whose route diverge from the requester,to generate multiple virtual trajectories to the LBS server so as to mislead *** results show that our proposed scheme achieves a high privacy-preserving level and outperforms other state-of-the-art schemes in terms of location entropy and tracking success ratio.

关键词： location privacy location-based service internet of vehicles vehicular networks

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A semi-analytical multi-harmonic balance method on full-3D contact model for dynamic analysis of dry friction systems

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Chinese Journal of Aeronautics 2024年第2期37卷 309-329页

作者： He SUN Dayi ZHANG Yaguang WU qingyang SHEN Dianyin hu Research Institute of Aero-Engine Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Key Laboratory of Aero-Engine Structure and Strength Beijing 100191China Sino-French Engineering School Beihang UniversityBeijing 100191China AECC Sichuan Gas Turbine Research Establishment Chengdu 610500China

Dry friction damping structures are widely-used in aero-engines to mitigate *** nonlinear nature of friction and the two-dimensional in-plane motion on the contact interface bring challenges to accurately and efficiently predict the forced response of frictionally damped *** state-of-the-art Multi-Harmonic Balance Method(MHBM)on quasi-3D contact model in engineering cannot precisely capture the kinematics on the friction interface although the efficiency is *** full-3D contact model can describe the constitutive relationship of the interface in a more accurate manner;however,the efficiency and convergence are not guaranteed for large-scale *** this paper,a semi-analytical MHBM on full-3D contact model is *** original Trajectory Tracking Method(TTM)for evaluating the contact force is reformulated to make the calculation more concise and the derivation of the Analytical Jacobian Matrix(AJM)*** on the chain rule of derivation,the AJM which is the core to upgrade the performance is *** a shrouded blade finite element model,the accuracy and efficiency of the proposed method are compared with both the MHBM on full-3D contact model with numerical Jacobian matrix and the MHBM on quasi-3D contact model with *** results show that the AJM improves significantly the efficiency of the MHBM on full-3D contact *** time cost of the proposed method is in the same order of magnitude as that of the MHBM on quasi-3D contact *** also confirm that the full-3D contact model is necessary for the dynamic analyses of shrouded *** one uses the quasi-3D model,the estimation relative error of damping can even reach 31.8%in some *** addition,the AJM also brings benefits for stability *** is highly recommended that engineers use the MHBM on full-3D contact model for the dynamic analysis and design of shrouded blades.

关键词： Dry friction damping Multi-harmonic balance method Trajectory tracking method Jacobian matrix Shrouded blade

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Catalytic transformation of 4-nitrophenol into 4-aminophenol over ZnO nanowire array-decorated Cu nanoparticles

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Green Chemical Engineering 2024年第2期5卷 205-212页

作者： Anlin Feng Chaoyu Lin huiqin Zhou Weihong Jin Yidong hu Dongyang Li qingyang Li Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China School of Chemical Engineering and Technology Hebei University of TechnologyTianjin300401China Department of Chemical and Materials Engineering University of AlbertaEdmontonT6G 2H5Canada

To realize economical and effective removal of hazardous 4-nitrophenol from the environment,we developed an easily recyclable ZnO nanowire array decorated with Cu *** salix argyracea-shaped structure not only provides a platform to achieve stable and good dispersion of Cu nanoparticles,but also offers a great deal of catalytically active *** density functional theory calculations reveal that ZnO and Cu have a very beneficial synergistic effect on their catalytic *** synergy is ascribed to the electronic localization occurring at ZnO/Cu interface,which helps improve Cu nanoparticle’s ability to adsorb electro-negatively 4-nitrophenolate ions and to capture hydrogen radicals,thereby accelerating the hydrogen transfer from metal hydride complex to *** from these characteristics,it exhibits high efficiency and reusability towards the catalytic reduction of waste 4-nitrophenol to valuable 4-aminophenol with a rate constant of 43.02×10^(-3)s^(-1)and an average conversion of 96.5%in 90 s during 10 *** activity is superior to that of most reported noble-or non-noble-metal powder,bulk,coating,and array catalysts,indicating its competitive advantages in cost and efficiency,as well as enticing application prospects.

关键词： ZnO nanowire Cu nanoparticle Nano-heterojunction 4-Nitrophenol catalytic reduction Density functional theory

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Heavy-atom engineered hypoxia-responsive probes for precisive photoacoustic imaging and cancer therapy

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Chinese Chemical Letters 2024年第4期35卷 316-320页

作者： Ling-Ling Wu Xiangchuan Meng qingyang Zhang Xiaowan Han Feiya Yang Qinghua Wang Hai-Yu hu Nianzeng Xing Department of Urology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China State Key Laboratory of Bioactive Substances and Function of Natural Medicine Institute of Materia MedicaPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100050China

Photoacoustic agents combining photodynamic therapy(PDT) and photothermal therapy(PTT) functions have emerged as potent theranostic agents for combating cancer. The molecular approaches for enhancing the near-infrared(NIR)-absorption and maximizing non-radiative energy transfer are essential for effective photoacoustic imaging(PAI) and therapy applications. In addition, such molecules with high specificity and affinity to cancer cells are urgently needed, which would further decrease the side effect during treatments. In this study, we applied a heavy-atom engineering strategy and introduced p-aminophenol,-thio, and-seleno moieties into NIR heptamethine cyanine(Cy7) skeleton(Cy7-X-NH_(2), X = O, S, Se) to significantly increase photothermal conversion efficiency for PTT and promote intersystem crossing for ***, we designed a series of nitroreductase(NTR)-activated photoacoustic probes(Cy7-X-NO_(2),X = O, S, Se), and target hypoxic tumors with NTR overexpression. Our prostate cancer targeting probe,Cy7-Se-NO_(2)-KUE, exhibited specific tumor photoacoustic signals and effective tumor killing through outstanding synergistic PTT/PDT in vivo. These findings highlighted a versatile strategy for cancer photoacoustic diagnosis and enhanced phototherapy.

关键词： Heavy-atom effect Phototherapy Photoacoustic imaging Hypoxia-responsive Prostate cancer

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Mixed-decomposed convolutional network:A lightweight yet efficient convolutional neural network for ocular disease recognition

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CAAI Transactions on Intelligence Technology 2024年第2期9卷 319-332页

作者： Xiaoqing Zhang Xiao Wu Zunjie Xiao Lingxi hu Zhongxi Qiu qingyang Sun Risa Higashita Jiang Liu Research Institute of Trustworthy Autonomous Systems and Department of Computer Science and Engineering Southern University of Science and TechnologyShenzhenChina Tomey Corporation NagoyaJapan Guangdong Provincial Key Laboratory of Brain‐inspired Intelligent Computation Department of Computer Science and EngineeringSouthern University of Science and TechnologyShenzhenChina Singapore Eye Research Institute SingaporeSingapore

Eye health has become a global health concern and attracted broad *** the years,researchers have proposed many state-of-the-art convolutional neural networks(CNNs)to assist ophthalmologists in diagnosing ocular diseases efficiently and ***,most existing methods were dedicated to constructing sophisticated CNNs,inevitably ignoring the trade-off between performance and model *** alleviate this paradox,this paper proposes a lightweight yet efficient network architecture,mixeddecomposed convolutional network(MDNet),to recognise ocular *** MDNet,we introduce a novel mixed-decomposed depthwise convolution method,which takes advantage of depthwise convolution and depthwise dilated convolution operations to capture low-resolution and high-resolution patterns by using fewer computations and fewer *** conduct extensive experiments on the clinical anterior segment optical coherence tomography(AS-OCT),LAG,University of California San Diego,and CIFAR-100 *** results show our MDNet achieves a better trade-off between the performance and model complexity than efficient CNNs including MobileNets and ***,our MDNet outperforms MobileNets by 2.5%of accuracy by using 22%fewer parameters and 30%fewer computations on the AS-OCT dataset.

关键词： artificial intelligence deep learning deep neural networks image analysis image classification medical applications medical image processing

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Pressure Distinguishes the Dual Emissions in Pseudohalide 2D Ruddlesden-Popper Perovskite Cs_(2)Pb(SCN)_(2)Br_(2)

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CCS Chemistry 2024年第7期6卷 1748-1756页

作者： Songhao Guo Yuhong Mao Congcong Chen Yao Zhang Guoxiang Zhao Kejun Bu qingyang hu Haiming Zhu Guifu Zou Wenge Yang Lingling Mao Xujie Lü Center for High Pressure Science and Technology Advanced Research(HPSTAR) Shanghai Department of Chemistry Southern University of Science and TechnologyShenzhen Department of Chemistry Zhejiang UniversityHangzhou College of Energy Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu ProvinceSoochow UniversitySuzhou

Two-dimensional(2D)Ruddlesden-Popper(RP)halide perovskites with diverse structures and properties have drawn increasing attention due to their promising optoelectronic ***,a new all-inorganic Cs_(2)Pb(SCN)_(2)Br_(2) has been reported that opens up new potential for the development of 2D RP ***,recent reports of unusual dual emissions and two-edge absorption in Cs_(2)Pb(SCN)_(2)Br_(2) have generated intense debate about its origin and remains ***,by combining continuous pressure tuning with in situ diagnostics,we have unambiguously revealed the underlying mechanisms that the 2D Cs_(2)Pb(SCN)_(2)Br_(2) exhibits an intrinsic blue emission at 2.66 eV and an absorption edge close to the emission *** the gradually formed CsPbBr_(3) is responsible for the green emission at 2.33 eV with the absorption shoulder at 2.41 ***,by fitting the temperature-dependent intensity of the intrinsic blue emission,we have determined the corrected value of exciton binding energy for 2D Cs_(2)Pb(SCN)_(2)Br_(2) to be 90 ***,an emission enhancement of 2.5 times is achieved in Cs_(2)Pb(SCN)_(2)Br_(2) under a mild pressure within 0.8 GPa,caused by the pressuresuppressed exciton-phonon *** work not only elucidates the origin of the dual emissions and two-edge absorption in Cs_(2)Pb(SCN)_(2)Br_(2),but it also provides a potential means to regulate and optimize the optoelectronic properties of 2D perovskites.

关键词： two-dimensional perovskite dual emissions two-edge absorption high pressure in situ characterization enhanced photoluminescence

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MEIC-global-CO_(2):A new global CO_(2)emission inventory with highly-resolved source category and sub-country information

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Science China Earth Sciences 2024年第2期67卷 450-465页

作者： Ruochong XU Dan TONG qingyang XIAO Xinying QIN Cuihong CHEN Liu YAN Jing CHENG Can CUI Hanwen hu Wenyu LIU Xizhe YAN huaxuan WANG Xiaodong LIU Guannan GENG Yu LEI Dabo GUAN Kebin HE Qiang ZHANG Department of Earth System Science Ministry of Education Key Laboratory for Earth System ModelingInstitute for Global Change StudiesTsinghua UniversityBeijing100084China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China Chinese Academy of Environmental Planning Beijing100041China Institute for Carbon Neutrality Tsinghua UniversityBeijing100084China

CO_(2)emission inventory provides fundamental data for climate research and emission ***,most global CO_(2)emission inventories were developed with energy statistics from International Energy Agency(IEA)and were available at country level with limited source ***,as the first step toward a high-resolution and dynamic updated global CO_(2)emission database,we developed a data-driven approach to construct seamless and highly-resolved energy consumption data cubes for 208 countries/territories,797 sub-country administrative divisions in 29 countries,42 fuel types,and 52 sectors,with the fusion of activity data from 24 international statistics and 65 regional/local *** CO_(2)emissions from fossil fuel combustion and cement production in 1970–2021 were then estimated with highly-resolved source category(1,484 of total)and sub-country information(797 of total).Specifically,73%of global CO_(2)emissions in 2021 were estimated with sub-country information,providing considerably improved spatial resolution for global CO_(2)emission *** the support of detailed information,the dynamics of global CO_(2)emissions across sectors and fuel types were presented,representing the evolution of global economy and progress of climate *** differences of sectoral contribution were found across sub-country administrative divisions within a given country,revealing the uneven distribution of energy and economic structure among different *** estimates were generally consistent with existing databases at aggregated level for global total or large emitters,while large discrepancies were observed for middle and small *** database,named the Multiresolution Emission Inventory model for Climate and air pollution research(MEIC)is publicly available through http://*** with highly-resolved information and timely update,which provides an independent carbon emission accounting data source for climate rese

关键词： CO_(2)emissions Data-driven approach Highly-resolved source category Sub-country information

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大气增氧机制:地球表层过程与深部氧化还原状态的耦合

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科学通报 2024年第2期69卷 253-267页

作者：胡清扬罗根明李元北京高压科学研究中心北京100193 中国地质大学(武汉)地球科学学院武汉430074 中国科学院广州地球化学研究所同位素地球化学国家重点实验室广州510640

氧气是地球表面生命蓬勃发展的关键物质.目前的地球化学模型和矿物学证据认为,大气中的氧气主要源自生物作用,如通过藻类生物的光合作用.尽管源自生物作用的产氧机制占据相关研究的主流,氧元素实际占据了地球内部最大的摩尔分数,因此它... 详细信息

氧气是地球表面生命蓬勃发展的关键物质.目前的地球化学模型和矿物学证据认为,大气中的氧气主要源自生物作用,如通过藻类生物的光合作用.尽管源自生物作用的产氧机制占据相关研究的主流,氧元素实际占据了地球内部最大的摩尔分数,因此它在调整地壳和地幔的氧化还原状态方面发挥着重要作用,地球深部氧化还原水平的波动会对大气中的氧分压产生深远影响.本综述聚焦地质历史中的大气增氧机制,结合最新的生物地球化学和矿物学发现,讨论大气氧来自地球表层和深层的源与汇.越来越多的工作揭示,地球深层可能存在一个隐藏的氧储库,一些重大地质事件与这一深部氧储库可能密切相关.

关键词：氧氧化还原状态矿物化学挥发分循环

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Applying an AIE type fluorescent probe in the detection of tetracycline antibiotics

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分子科学学报 2024年第2期40卷 146-152页

作者： hu Bo ZHENG Luying WANG Rui XU Kun ZHAO Sisi YU Zhan CHEN qingyang ZHANG Hang College of Chemistry and Chemical Engineering Shenyang Normal UniversityShenyang 110034China

The typical representative TPB(tetraphenyl-1,3-butadiene)molecule with AIE effect was used as a fluorescent probe,and the specific recognition of tetracycline antibiotics was achieved through the comparison of the experimental results of the quenching of TPB by nine antibiotics of different types,which indicated that tetracycline antibiotics were found to quench TPB to the greatest extent,while the quenching of other antibiotics(***,aminoglycoside,sulfonamides,and quinolone)was not *** the quantitative relationship between the concentration of antibiotic solution and the effect of fluorescence quench was investigated by taking oxytetracycline among tetracycline antibiotics as an example,and the detection limit was ***,it was found that the UV absorption spectra of tetracycline hydrochloride and the fluorescence excitation spectra of TPB had high overlap,while the overlap between the UV absorption spectra of other antibiotics,such as sulfadimethoxine,and the fluorescence laser spectrum of TPB was low,which fulfilled the fluorescence internal filtering *** fluorescence probe has stable properties,low cost and strong anti-interference ability,which makes the method more valuable in the practical detection of *** study indicates great potent in the detection of antibiotics.

关键词： fluorescence detection technology tetraphenyl-1,3-butadiene tetracycline antibiotics

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