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Optical coherence tomography angiography of optic disc perfusion in non-arteritic anterior ischemic optic neuropathy

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International Journal of Ophthalmology(English edition) 2017年第9期10卷 1402-1406页

作者： Jia-Wen Ling Xue yin qian-yi Lu yi-yi Chen pei-Rong Lu Department of Ophthalmology the First Affiliated Hospital of Soochow University Department of Ophthalmology the Third People's Hospital of Zhangjiagang

AIM：To compare the optic disc blood flow of non-arteritic ischemic optic neuropathy（NAION）eyes with normal ***：The optic disc blood flow densities of diagnosed non-acute phase NAION eyes（21 eyes,14 individuals）and normal eyes（19 eyes,12 individuals）were detected via Optovue optical coherence tomography angiography（OCTA）.The optic disc blood flow was measured via Image J *** between optic disc perfusion and visual function variables were assessed by linear regression ***：The average percentage of the optic disc nonperfusion areas in the non-acute phase NAION patients（17.84%±6.18%）was increased,when compared to the normal control eyes（8.61%±1.65%）,and the difference was statistically significant（P〈0.01）.Moreover,there was a proportional correlation between the visual field mean defect（MD）and the optic disc non-perfusion area percentage,and the relationship was statistically significant（t=3.65,P〈0.01,R2=0.4118）.In addition,the critical correlation between the best corrected visual acuity（BCVA）and the optic disc non-perfusion area percentage was statistically significant（t=4.32,P〈0.01,R2=0.4957）.CONCLUSION：The optic disc non-perfusion area percentages detected via OCTA in NAION eyes were significantly increased when compared with the normal *** the BCVA and MD were correlated with the optic disc flow detected,revealing that OCTA may be valuable in the diagnosis and estimation of NAION.

关键词： non-arteritic anterior ischemic optic neuropathy optical coherence tomography angiography visual field visualacuity

Deeply missing my career idol and role model--Professor Perry ***

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Frontiers of Environmental Science & Engineering 2023年第9期17卷 257-258页

作者： yi qian School of Environment Tsinghua UniversityBeijing 100084China

Upon hearing the news of Professor Perry ***’s passing,I felt deeply saddened and heartbroken,and was unable to contain my emotions.I couldn’t help but reminiscing about the cherished moments we shared together and the valuable lessons I learned from him over the years.I first met Professor Perry *** in *** the opportunity of attending a conference in the United States,I visited Professor McKinney at the University of Kansas,the first American expert in my field that I had ever known of.I told him that I was very interested in Professor McCarty’s research on aerobic bio-filters and wanted to learn more.“Let me give Perry a call,”he said immediately,and in less than five minutes,Perry and I became *** turned out that Professor McKinney had been Professor McCarty’s teacher and mentor in the past.I changed my flight immediately and flew to California the next day,where I met Professor McCarty,a world-renowned expert in water pollution control,and visited the aerobic bio-filter he established and their water pollution control *** had inspiring yet amiable conversations,and a friendship that lasted for over 30 years ensued.

关键词： visited career missing

Multi-target tracking algorithm based on PHD filter against multi-range-false-target jamming

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Journal of Systems Engineering and Electronics 2020年第5期31卷 859-870页

作者： TIAN Chen pei Yang HOU Peng ZHAO qian School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

Multi-range-false-target(MRFT) jamming is particularly challenging for tracking radar due to the dense clutter and the repeated multiple false targets. The conventional association-based multi-target tracking(MTT) methods suffer from high computational complexity and limited usage in the presence of MRFT *** order to solve the above problems, an efficient and adaptable probability hypothesis density(PHD) filter is proposed. Based on the gating strategy, the obtained measurements are firstly classified into the generalized newborn target and the existing target measurements. The two categories of measurements are independently used in the decomposed form of the PHD filter. Meanwhile,an amplitude feature is used to suppress the dense clutter. In addition, an MRFT jamming suppression algorithm is introduced to the filter. Target amplitude information and phase quantization information are jointly used to deal with MRFT jamming and the clutter by modifying the particle weights of the generalized newborn targets. Simulations demonstrate the proposed algorithm can obtain superior correct discrimination rate of MRFT, and high-accuracy tracking performance with high computational efficiency in the presence of MRFT jamming in the dense clutter.

关键词： multi-range-false-target(MRFT)jamming multi-target tracking(MTT) probability hypothesis density(PHD) target amplitude feature gating strategy

A Secure and Efficient Handover Authentication and Key Management Protocol for 5G Networks

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Journal of Communications and Information Networks 2020年第1期5卷 40-49页

作者： Jiaqi Huang yi qian Department of Electrical and Computer Engineering University of Nebraska-Lincoln1110 S 67th StreetOmahaNE 68182USA

As a major component of thefifth-generation(5G)wireless networks,network densification greatly increases the network capacity by adding more cell sites into the ***,the densified network increases the handover frequency of fast-moving mobile users,like ***,seamless handover with security provision is highly desirable in 5G *** third generation partnership project(3GPP)has been working on standardization of the handover procedure in 5G networks to meet the stringent efficiency and security ***,the existing handover authentication process in 5G networks has securityflaws,*** to replay and de-synchronization attacks,and cannot provide perfect forward *** this paper,we propose a secure and efficient handover authentication and key management protocol utilizing the Chinese remainder *** proposed scheme preserves the majority part of the original 5G system architecture defined by 3GPP,thus can be easily implemented in *** security analysis based on BAN-logic shows that the proposed scheme achieves secure mutual authentication and can remedy some security flaws in original 5G handover *** analysis shows that the proposed protocol has lower communication overhead and computation overhead compared with other handover authentication schemes.

关键词： 5G wireless network handover authentication key management security

Drivers of the differentiation between broad-leaved trees and shrubs in the shift from evergreen to deciduous leaf habit in forests of eastern Asian subtropics

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Plant Diversity 2023年第5期45卷 535-543页

作者： yi Jin Hong qian Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China Guizhou Normal UniversityGuiyang 550025China Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL62703USA

In eastern Asian subtropical forests,leaf habit shifts from evergreen to deciduous broad-leaved woody plants toward higher *** shift has been largely explained by the greater capacity of deciduous broad-leaved plants to respond to harsh climatic conditions(e.g.,greater seasonality).The advantages of deciduous leaf habit over evergreen leaf habit in more seasonal climates have led us to hypothesize that leaf habits would shift in response to climate changes more conspicuously in forest canopy trees than in forest understory ***,we hypothesize that in the forests of the subtropics,plants at higher latitudes,regardless of growth form,would better tolerate seasonal harsh climates,and hence show less differentiation in leaf habit shift,compared to those at lower *** test these two hypotheses,we modelled the proportion of deciduous broad-leaved species and the incidence of deciduous and evergreen broad-leaved species in woody angiosperm species compositions of ten largesized forest plots distributed in the Chinese *** found that the rate of leaf habit shift along a latitudinal gradient was higher in forest trees than in forest *** also found that the differentiation in leaf habit shift between trees and shrubs is greater at lower latitudes(i.e.,warmer climates)than at higher latitudes(i.e.,colder climates).These findings indicate that specialized forest plants are differentially affected by climate in distinct forest strata in a manner dependent on latitudinal *** differences in forest plant response to changes in climate suggest that global climate warming will alter growth forms and geographical distributions and ranges of forests.

关键词： Functional trait Leaf life span Forest dynamics plot Latitudinal gradient

Are phylogenies resolved at the genus level appropriate for studies on phylogenetic structure of species assemblages?

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Plant Diversity 2021年第4期43卷 255-263页

作者： Hong qian yi Jin Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL62703USA Key Laboratory of State Forestry Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China Guizhou Normal UniversityGuiyang550025China

Phylogenies are essential to studies investigating the effect of evolutionary history on assembly of species in ecological communities and geographical and ecological patterns of phylogenetic structure of species *** phylogenies well resolved at the species level are lacking for many major groups of organisms such as vascular plants,researchers often generate a species-level phylogenies using a phylogeny well resolved at the genus level as a backbone and attaching species to their respective genera in the phylogeny as polytomies or by using a megaphylogeny well resolved at the genus level as a backbone and adding additional species to the megaphylogeny as polytomies of their respective ***,whether the result of a study using species-level phylogenies generated in these ways is robust,compared to that based on phylogenies fully resolved at the species level,has not been ***,we use 1093 angiosperm tree assemblages(each in a 110110 km quadrat)in North America as a model system to address this question,by examining six commonly used metrics of phylogenetic structure(phylogenetic diversity and phylogenetic relatedness)and six climate variables commonly used in *** results showed that(1)the scores of phylogenetic metrics derived from species-level phylogenies resolved at the genus level with species being attached to their respective genera as polytomies are very strongly or perfectly correlated to those derived from a phylogeny fully resolved at the species level(the mean of correlation coefficients is 0.973),and(2)the relationships between the scores of phylogenetic metrics and climate variables are consistent between the two sets of analyses based on the two types of *** study suggests that using species-level phylogenies resolved at the genus level with species being attached to their genera as polytomies is appropriate in studies exploring patterns of phylogenetic structure of species in ecological communities

关键词： Genus-level phylogeny Species-level phylogeny Phylogenetic diversity Phylogenetic relatedness Community phylogenetics Environmental gradient

Spectra of rational orthonormal systems

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Science China Mathematics 2019年第10期62卷 1961-1976页

作者： Qiuhui Chen pei Dang Tao qian Department of Mathematics College of Mathematics and InformaticsSouth China Agricultural UniversityGuangzhou510642China Faculty of Information Technology Macao University of Science and TechnologyMacaoChina Macao Institute of Systems Engineering Macao University of Science and TechnologyMacaoChina

We use the Weyl correspondence approach to investigate the spectral operators of the Laguerre and the Kautz systems. We show that the basic functions in the Laguerre and the Kautz systems are the eigenvectors of modified Sturm-Liouville operators. The results are further generalized to multiple parameters of one complex variable in both the unit disc and the upper half-plane contexts.

关键词： spectral operator Laguerre and Kautz systems TM system Caley transform Heisenberg group Weyl correspondence

***: An R package that can generate large phylogenetic trees for plants and animals

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Plant Diversity 2023年第3期45卷 347-352页

The previously released packages of the PhyloMaker series(***,***,and ***2) have been broadly used to generate phylogenetic trees for ecological and biogeographical *** these packages can be used to generate phylogenetic trees for any groups of plants and animals for which megatrees are available,they focus on generating phylogenetic trees for plants based on the megatrees provided by the *** to use these packages to generate phylogenetic trees based on other megatrees is not ***,we present a new tool,which is called ‘***’,and a simple R script that can be used to easily generate large phylogenetic trees for both plants and animals at a relatively fast speed.

关键词： Animals Community phylogenetics Megatree Phylogeny Plants Species list

Predicting the shrinkage of thermal insulation mortar by probabilistic neural networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第3期11卷 212-222页

作者： yi-qun DENG pei-ming WANG Key Laboratory of Advanced Civil Engineering Materials Ministry of EducationTongji UniversityShanghai 200092China

This study explored the potential of using probabilistic neural networks (PNN) to predict shrinkage of thermal insulation *** results were obtained from the PNN model with the aid of Parzen non-parametric estimator of the probability density functions (PDF).Five variables,water-cementitious materials ratio,content of cement,fly ash,aggregate and plasticizer,were employed for input variables,while a category of 56-d shrinkage of mortar was used for the output variable.A total of 192 groups of experimental data from 64 mixtures designed using JMP7.0 software were collected,of which 120 groups of data were used for training the model and the other 72 groups of data for *** simulation results showed that the PNN model with an optimal smoothing parameter determined by the curves of the mean square error (MSE) and the number of unrecognized probability densities (UPDs) exhibited a promising capability of predicting shrinkage of mortar.

关键词： Mortar Shrinkage Probabilistic neural networks (PNN) Thermal insulation