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Quantum receiver enhanced by adaptive learning

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Light(Science & Applications) 2022年第12期11卷 3080-3086页

作者： Chaohan Cui William Horrocks Shuhong Hao Saikat Guha Nasser Peyghambarian Quntao Zhuang Zheshen Zhang James C.Wyant College of Optical Sciences University of ArizonaTucsonAZ 85721USA Department of Materials Science and Engineering University of ArizonaTucsonAZ 85721USA Department of Electrical and Computer Engineering University of ArizonaTucsonAZ 85721USA Department of Electrical and Computer Engineering University of Southern CaliforniaLos AngelesCA 90089USA Department of Electrical Engineering and Computer Science University of MichiganAnn ArborMI 48109USA

Quantum receivers aim to effectively navigate the vast quantum-state space to endow quantum information processing capabilities unmatched by classical *** date,only a handful of quantum receivers have been constructed to tackle the problem of discriminating coherent *** receivers designed by analytical approaches,however,are incapable of effectively adapting to diverse environmental conditions,resulting in their quickly diminishing performance as the operational complexities ***,we present a general architecture,dubbed the quantum receiver enhanced by adaptive learning,to adapt quantum receiver structures to diverse operational *** adaptively learned quantum receiver is experimentally implemented in a hardware platform with record-high *** the architecture and the experimental advances,the error rate is reduced up to 40%over the standard quantum limit in two coherent-state encoding schemes.

关键词： quantum coherent matched

Peat record reflecting Holo-cene climatic change in the Zoige Plateau and ams radiocarbon dating

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Chinese Science Bulletin 2002年第1期47卷 66-70页

作者： ZHOU Weijian LU Xuefeng WU Zhengkun DENG Lin A.J.T.Jull D.Donahue W.Beck State Key Lab of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710054China Nnsf-ams facility University of Arizona

Through the use of reliable ams dating of high resolution (15-30 years) peat and the establishment of monsoon climate proxies sequence, we have been able to recognize several cold, dry events in the Tibetan Plateau during the Holocene. The more obvious ones occurred around 12800, 11300, 10200, 9580, 8900, 6400, 4400, 3700, 2800 and 1500 cal. aBP. These events correlate well with both ice rafting events recorded in high latitude North Atlantic Ocean sediment cores and cooling events in the low latitude SST. Spectral analysis indicates high frequency climate variation on centennial-millennial time scale during the Holocene. This further reflects Holocene climate instability and the existence of centennial-millenium scale rhythm in mid latitude areas as well.

关键词： Zoige Holocene high-resolution record peat ams dating climate instability.

Vegetation productivity responses to drought on tribal lands in the four corners region of the Southwest usa

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Frontiers of Earth Science 2018年第1期12卷 37-51页

作者： Mohamed Abd Salam EL-VILALY Kamel DIDAN Stuart E. MARSH Willem J.D. VAN LEEUWEN Michael A. CRIMMINS Armando Barreto MUNOZ The Intemational Food Policy Research Institute Washington DC 20006-1002 USA Vegetation Index and Phenology Lab Department of Agricultural and Biosystems Engineering The University of Arizona Tucson AZ 85721-0036 USA arizona Remote Sensing Center School of Natural Resources and the Environment The University of Arizona Tucson AZ 85721-0043 USA Department of Soils Water and Environmental Science The University of Arizona Tucson AZ 85721-0038 USA

For more than a decade, the Four Comers Region has faced extensive and persistent drought conditions that have impacted vegetation communities and local water resources while exacerbating soil erosion. These persistent droughts threaten ecosystem services, agriculture, and livestock activities, and expose the hypersensitivity of this region to inter-annual climate variability and change. Much of the intermountain Western United States has sparse climate and vegetation monitoring stations, making fine-scale drought assessments difficult. Remote sensing data offers the opportunity to assess the impacts of the recent droughts on vegetation productivity across these areas. Here, we propose a drought assessment approach that integrates climate and topographical data with remote sensing vegetation index time series. Multisensor Normalized Difference Vegetation Index （NDVI） time series data from 1989 to 2010 at 5.6 km were analyzed to characterize the vegetation productivity changes and responses to the ongoing drought. A multi-linear regression was applied to metrics of vegetation productivity derived from the NDVI time series to detect vegetation productivity, an ecosystem service proxy, and changes. The results show that around 60.13% of the study area is observing a general decline of greenness （p 〈 0.05）, while 3.87% show an unexpected green up, with the remaining areas showing no consistent change. Vegetation in the area show a significant positive correlation with elevation and precipitation gradients. These results, while, confirming the region＇s vegetation decline due to drought, shed further light on the future directions and challenges to the region＇s already stressed ecosystems. Whereas the results provide additional insights into this isolated and vulnerable region, the drought assessment approach used in this study may be adapted for application in other regions where surfacebased climate and vegetation monitoring record is spatially and temporally limited.

关键词： drought remote sensing Hopi Navajo Nation

Aspects of rock permeability

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Frontiers of Structural and Civil Engineering 2013年第2期7卷 102-116页

作者： Lianyang ZHANG Department of Civil Engineering and Engineering Mechanics University of ArizonaTucsonArizona 85721USA

Effective evaluation of rock permeability is required in different energy,engineering and environmental *** much research has been conducted on rock permeability,it is still one of the most difficult tasks for practicing rock engineers to accurately determine rock *** on a comprehensive literature review,this paper outlines the key aspects of rock permeability by presenting the representative values of the permeability of different rocks,describing the empirical and semi-empirical correlations for estimating the permeability of rocks,and discussing the main factors affecting the permeability of *** factors discussed include stress,depth,temperature,and discontinuity intensity and *** paper also highlights the scale effect on rock permeability,interconnectivity of discontinuities,and anisotropy of rock *** paper provides the fundamental and essential information required for effective evaluation of rock permeability.

关键词： rock permeability discontinuity stress temperature scale effect anisotropy

EXTENSION OF RANGE IN RADIAL ORDER IN DETECTION AND MODE CLASSIFICATION OF SOLAR LOW-DEGREE GRAVITY MODES

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Science China Mathematics 1990年第7期33卷 854-866页

作者： HENRY A.HILL 顾益民Department of Physics university of arizona Tucson AZ 85721 usa Department of Physics University of Arizona Tucson AZ 85721 USA

The 1979 differential radius observations of the Sun have been reexamined for additional evidence of gravity modes (g-modes) beyond that reported by Hill and to classify the modes for which evidence has been obtained. The basic criteria employed in the mode detection and classification procedure are extensions of the criteria introduced by Hill. The properties of the 31 multiplets classified by Hill are used as the starting point in the work reported here. Statistically significant evidence of additional g-modes has been found and the number of classified multiplets is extended from 31 to 53. The degrees and radial orders of the 53 multiplets are respectively l=1, n=47,…, 7; l=2, n=6,…, 13, 15 and 16; l=3, n=7,…, 20; l=4, n=7,…, 20; and l=5, n=16,…, 26. The m=0 eigenfrequencies are measured with an accuracy of ≈0.02 μHz and the multiplet structure linear in angular order m is measured with an accuracy of ≈0.01 μHz.

关键词： Sun: oscillations Sun: internal structure.

Evaluation of rock mass deformability using empirical methods-A review

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Underground Space 2017年第1期2卷 1-15页

作者： Lianyang Zhang Department of Civil Engineering and Engineering Mechanics University of ArizonaTucsonArizona 85721United States

Evaluation of rock mass deformability is an important but very challenging task in the analysis and design of underground structures in *** various empirical(correlation)methods have been developed for determining the deformation modulus of rock masses,they come in many forms and are scattered in different *** is often difficult,time-consuming,or even impossible for a practitioner to find appropriate information to determine the deformation modulus of rock masses for a particular ***,this paper first provides a comprehensive review of the different empirical methods for determining the deformation modulus of rock *** a comparative analysis and discussion is carried out on the accuracy and main issues of these *** many of the empirical methods for determining the deformation modulus of rock masses need to use the deformation modulus of intact rock,the various empirical methods for estimating the deformation modulus of intact rock are also *** addition,this paper highlights the scale effect on rock mass deformability,the effect of confining stress on rock mass deformability,and the anisotropy of rock mass *** this paper outlines the key aspects of rock mass deformability and provides the fundamental and essential information required for effective evaluation of rock mass deformability using the empirical methods.

关键词： Rock mass Deformability Empirical method Scale effect Stress effect Anisotropy

A new horizon for neuroscience:terahertz biotechnology in brain research

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Neural Regeneration Research 2025年第2期20卷 309-325页

作者： Zhengping Pu Yu Wu Zhongjie Zhu Hongwei Zhao Donghong Cui Shanghai Key Laboratory of Psychotic Disorders Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Department of Psychiatry Kangci Hospital of JiaxingTongxiangZhejiang ProvinceChina Shanghai Synchrotron Radiation facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghaiChina Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of ScienceShanghaiChina National facility for Protein Science in Shanghai Shanghai Advanced Research InstituteChinese Academy of SciencesShanghaiChina

Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain *** this article,we review the development of terahertz biotechnology and its applications in the field of *** evidence indicates promising prospects for the use of terahertz spectroscopy and terahertz imaging techniques in the diagnosis of amyloid disease,cerebrovascular disease,glioma,psychiatric disease,traumatic brain injury,and myelin *** vitro and animal experiments have also demonstrated the potential therapeutic value of terahertz technology in some neuropsychiatric *** the precise underlying mechanism of the interactions between terahertz electromagnetic waves and the biosystem is not yet fully understood,the research progress in this field shows great potential for biomedical noninvasive diagnostic and therapeutic ***,the biosafety of terahertz radiation requires further exploration regarding its two-sided efficacy in practical *** review demonstrates that terahertz biotechnology has the potential to be a promising method in the field of neuropsychiatry based on its unique advantages.

关键词： biological effect brain neuron neuropsychiatry neuroscience non-thermal effect terahertz imaging terahertz radiation terahertz spectroscopy terahertz technology

A DIAGONAL SPLIT-CELL MODEL FOR THE OVERLAPPING YEE FDTD METHOD

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Acta Mathematica Scientia 2009年第6期29卷 1670-1676页

作者： Jinjie Liu Moysey Brio Jerome V. Moloney Department of Mathematical Sciences Delaware State University Dover DE 19901 USA arizona Center for Mathematical Sciences Department of Mathematics University of Arizona Tucson AZ 85721 USA

In this paper, we present a nonorthogonal overlapping Yee method for solv- ing Maxwell＇s equations using the diagonal split-cell model. When material interface is presented, the diagonal split-cell model does not require permittivity averaging so that better accuracy can be achieved. Our numerical results on optical force computation show that the standard FDTD method converges linearly, while the proposed method achieves quadratic convergence and better accuracy.

关键词： FDTD method Overlapping Yee method Maxwell's equations Optical force

Reversible and Reproducible Giant Universal Electroresistance Effect

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Chinese Physics Letters 2011年第10期28卷 217-219页

作者： SYED Rizwan ZHANG Sen YU Tian ZHAO Yong-Gang ZHANG Shu-Feng HAN Xiu-Feng Institute of Physics Chinese Academy of SciencesBeijing 100190 Department of Physics Tsinghua UniversityBeijing 100084 Department of Physics University of ArizonaTucsonArizona 85721USA

After the prediction of the giant electroresistance effect,much work has been carried out to find this effect in practical *** demonstrate a novel way to obtain a large electroresistance(ER)effect in the multilayer system at room *** current-in-plane(CIP)electric transport measurement is performed on the multilayer structure consisting of(011)-Pb(Mg_(1/3)Nb_(2/3))O_(3)−PbTiO_(3)(PMN−PT)/Ta/Al-O/*** is found that the resistance of the top metallic layer shows a hysteretic behavior as a function electric field,which corresponds well with the substrate polarization versus electric field(P–E)*** reversible hysteretic R–E behavior is independent of the applied magnetic field as well as the magnetic structure of the top metallic layer and keeps its memory *** novel memory effect is attributed to the polarization reversal induced electrostatic potential,which is felt throughout the multilayer stack and is enhanced by the dielectric Al-O layer producing unique hysteretic,reversible,and reproducible resistance switching *** novel universal electroresistance effect will open a new gateway to the development of future multiferroic memory devices operating at room temperature.

关键词： resistance multilayer effect