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International Journal of digital Earth 2022年第1期15卷 2422-2439页

作者： Zohreh Alijani Julien Meloche Alexander McLaren John Lindsay Alexandre Roy aaron Berg department of Geography Environment and GeomaticsUniversity of GuelphGuelphCanada département de Géomatique Appliquée Université de SherbrookeSherbrookeCanada département des Sciences de l’Environment Université du Québec à Trois-RivièresTrois-RivièresCanada

Surface roughness plays an important role in microwave remote *** the agricultural domain,surface roughness is crucial for soil moisture retrieval methods that use electromagnetic surface scattering or microwave radiative transfer ***,improved characterization of Soil Surface Roughness(SSR)is of considerable *** this study,three approaches,including a standard pin profiler,a LidAR point cloud generated from an iPhone 12 Pro,and a Structure from Motion(SfM)photogrammetric point cloud,were applied over 24 surface profiles with different roughness variations to measure surface *** objective of this study was to evaluate the capability of smartphone-based LidAR technology to measure surface roughness parameters and compare the results of this technique with the more common *** showed that the iPhone LidAR technology,when point cloud data is captured in a fine-resolution mode,has a significant correlation with SfM photogrammetry(R2=0.70)and a relatively close agreement with pin profiler(R2=0.60).However,this accuracy tends to be greater for random surfaces and rough profiles with row structure *** results of this study confirm that smartphone-based LidAR can be used as a cost-effective,fast,and time-efficient alternative tool for measuring surface roughness,especially for rough,wide,and inaccessible areas.

关键词： LidAR surface roughness structure from motion iPhone pin profiler

Broadband achromatic dielectric metalenses

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Light(Science & Applications) 2018年第1期7卷 236-246页

作者： Sajan Shrestha Adam C.Overvig Ming Lu aaron Stein Nanfang Yu department of Applied Physics and Applied Mathematics Columbia UniversityNew YorkNY 10027USA Brookhaven National Laboratory Center for Functional NanomaterialsUptonNY 11973USA

Metasurfaces offer a unique platform to precisely control optical wavefronts and enable the realization of flat lenses,or metalenses,which have the potential to substantially reduce the size and complexity of imaging systems and to realize new imaging ***,it is a major challenge to create achromatic metalenses that produce a single focal length over a broad wavelength range because of the difficulty in simultaneously engineering phase profiles at distinct wavelengths on a single *** practical applications,there is a further challenge to create broadband achromatic metalenses that work in the transmission mode for incident light waves with any arbitrary polarization *** developed a design methodology and created libraries of meta-units—building blocks of metasurfaces—with complex cross-sectional geometries to provide diverse phase dispersions(phase as a function of wavelength),which is crucial for creating broadband achromatic *** elucidated the fundamental limitations of achromatic metalens performance by deriving mathematical equations that govern the tradeoffs between phase dispersion and achievable lens parameters,including the lens diameter,numerical aperture(NA),and bandwidth of achromatic *** experimentally demonstrated several dielectric achromatic metalenses reaching the fundamental *** metalenses work in the transmission mode with polarization-independent focusing efficiencies up to 50%and continuously provide a near-constant focal length over λ=1200–1650 *** unprecedented properties represent a major advance compared to the state of the art and a major step toward practical implementations of metalenses.

关键词： chromatic dielectric limitations

神经退行性疾病“不可成药”靶点的小分子靶向策略

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Science Bulletin 2023年第16期68卷 1715-1718页

作者：卢俊梅李朝阳 aaron d.Gitler 鲁伯埙 Neurology department at Huashan Hospital State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceNew Cornerstone Science LaboratorySchool of Life SciencesFudan UniversityShanghai 200438China department of Genetics Stanford UniversityStanfordCA 94305USA Chan Zuckerberg Biohub-San Francisco San FranciscoCA 94158USA

As our population continues to age,neurodegenerative diseases are increasing in prevalence and taking a greater toll on *** devastating diseases are disparate in their clinical presentationÐsome affect memory while others affect *** despite those differences,a common theme uniting most neurodegenerative disorders is that misfolded proteins accumulate in the brains of patients afflicted with these *** genetics discoveries have strongly implicated the accumulation of misfolded proteins as drivers of disease ***,making drugs to target these disease proteins has been challenging,owing to them being‘‘misfoldedºand thus their lack of classic activity‘‘pocketsº,whose occupancy by small molecules influences a protein’s biochemical function.

关键词：神经退行性疾病 diseases drugs

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孔隙介质中含砷聚集物的三维成像

西南交通大学学报 2011年第6期46卷 973-978页

作者：彭道平黄涛 aaron PACKMAN 西南交通大学地球科学与环境工程学院四川成都610031 美国西北大学土木与环境工程系伊利诺伊州埃文斯顿60208

为观测砷沉积导致的孔隙介质内部结构的改变,采用X射线差异微断层扫描技术,扫描从Loa流域获得的河床沉积物和实验室配制的含砷样品,对含砷聚集物在孔隙介质中的分布进行了成像分析.经过图像处理去除图像上的噪点和增强图像中砷的信息,... 详细信息

为观测砷沉积导致的孔隙介质内部结构的改变,采用X射线差异微断层扫描技术,扫描从Loa流域获得的河床沉积物和实验室配制的含砷样品,对含砷聚集物在孔隙介质中的分布进行了成像分析.经过图像处理去除图像上的噪点和增强图像中砷的信息,获得了孔隙介质中含砷聚集物的三维数据组;采用Avizo 6和Blob3d等工具,对三维数据组进行重建和可视化.成像显示:大量含砷聚集物沉积在介质孔隙和介质表面;不同尺寸聚集物的形态呈现出明显的多样化特征———小颗粒聚集物趋于球形,大颗粒聚集物则趋于扁平状.研究表明,该技术可在不破坏样品的前提下,实现对孔隙介质沉积前后内部结构变化的直接观测.

关键词：孔隙介质 X射线差异微断层扫描技术砷图像处理三维成像

Efficient Convex Optimization Approaches to Variational Image Fusion

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Numerical Mathematics(Theory,Methods and Applications) 2014年第2期7卷 234-250页

作者： Jing Yuan Brandon Miles Greg Garvin Xue-Cheng Tai aaron Fenster Medical Imaging Lab Robarts Research InstituteUniversity of Western OntarioLondon ONCanada N6A 5B7 department of Medical Imaging St Jospeh’s HealthCareLondon ONCanada department of Mathematics University of BergenBergenNorway

Image fusion is an imaging technique to visualize information from multiple imaging sources in one single image,which is widely used in remote sensing,medical imaging *** this work,we study two variational approaches to image fusion which are closely related to the standard TV-L_(2) and TV-L_(1) image approximation *** investigate their convex optimization formulations,under the perspective of primal and dual,and propose their associated new image decomposition *** addition,we consider the TV-L_(1) based image fusion approach and study the specified problem of fusing two discrete-constrained images f_(1)(x)∈L_(1) and f_(2)(x)∈L_(2),where L_(1) and L_(2) are the sets of linearly-ordered discrete *** prove that the TV-L_(1) based image fusion actually gives rise to the exact convex relaxation to the corresponding nonconvex image fusion constrained by the discretevalued set u(x)∈L_(1)∪L_(2).This extends the results for the global optimization of the discrete-constrained TV-L_(1) image approximation[8,36]to the case of image *** a big numerical advantage of the two proposed dual models,we show both of them directly lead to new fast and reliable algorithms,based on modern convex optimization *** with medical images,remote sensing images and multi-focus images visibly show the qualitative differences between the two studied variational models of image *** also apply the new variational approaches to fusing 3d medical images.

关键词： Convex optimization primal-dual programming combinatorial optimization totalvariation regularization image fusion

The Trilateral Relations Between the US,China, and the Philippines:a Model of Interaction Between One Small State and Two Big Powers

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The Trilateral Relations Between the US,China, and the Phili...

作者： aaron Jed Rabena（瑞杰龙）山东大学

学位级别：硕士

本文主要考察了一个小国与两个大国之间的互动关系。案例分析选取了作为小国的菲律宾与美国和中国的互动。本研究的重要性是要厘清在三边关系形成中发挥作用的变量,包括内在的或称体系的因素、国际组织等新行为体的作用等。为研究三边... 详细信息

本文主要考察了一个小国与两个大国之间的互动关系。案例分析选取了作为小国的菲律宾与美国和中国的互动。本研究的重要性是要厘清在三边关系形成中发挥作用的变量,包括内在的或称体系的因素、国际组织等新行为体的作用等。为研究三边关系中,各种主要的和复杂的关系,本文借助有关理论工具构建起了三边关系的互动框架,这有助于我们弄清楚互动关系的各种类型与层次。上述分析框架有助于我们把握菲律宾、美国与中国互动关系的整体图景。美国总统巴拉克·奥巴马近期关于重返亚洲的声明引起了广泛关注：美国将如何制定一个新的再同盟战略?这对美国在该地区的外交、政治、安全和经济利益有很大影响——它是国际关系主要方面。在国际体系中,国家有不同的能力,扮演不同角色。比如小国,中等国家,还有大国。在本文的案例中涉及三边关系中一个小国和两个大国组成一个特殊的权力分布。国家行为主要遵循现实主义和新现实主义理解,或者自由主义,建构主义和新自由主义理论。在后冷战世界,考虑到经济作为所有国家的生命线具有更高的重要性,国家已经倾向于后者。一个小国与一个大国的关系可能是独立的、协调的、缓和的、交战的、服从的、一致的、结盟的、追随的和不对称的。大国与其他国家的关系可能是均势的、保护的、相互依赖的、对称的和战略伙伴关系。因此,三角形成为一个新聚会的舞台,它使双方关系成为三边关系,诱发有关偏好与敌对的选择。考虑到许多结构自由主义机制的诞生,三边关系现在是复杂的。比如联合国及东盟,这些非国家行为体常常伴随着非传统安全和跨国家议题,它们引起了许多国家的注意。需要指出,国际制度作为新加入的变量发挥重要作用,它的重要性体现在国际组织会议和峰会上,领导人进行会谈和讨论。因此,国际组织延伸了国家领导人的互动,比通常国家互访更具个人和非正式的色彩。在这样的互动过程中,为新行动路线提出、新思想和新提议能撇开单纯的峰会议事日程谈话而达到效果。互惠限制只可能发生在一种情况,即当所有制国家——无论小国、中等中国或大国都被成员国身份约束在一个国际机制中,并由一揽子政策保证所有国家服从——无论国家大小。这种方式,较小国家通过政策安全网能邀请较大国家加入。同时,较大国家通过它们的成员国身份也能塑造一些小国的偏好,并影响整个组织。本质上,双边关系发生变化将影响到三边关系中的另一方,并影响整个三边互动关系发生结构上的转变。这种影响可能是包含的、排异的或是交互影响的。判定该互动模型有两点：一是必须考察小国和大国的互动,二是两大国具有互动关系。我们认为,两个大国中其一为地区性大国,另一为世界大国很重要。考虑到历史、政治系统、利益、国家角色、价值、联盟、伙伴关系、文化和外交政策,小国的互动将与两大国都不相同。不同于冷战期间存在于中美苏之间的战略三角关系,从新现实主义和新自由主义理论观点中产生出的每个双方和三方更像是实用主义关系。三方关系中的双方关系层面至关重要,因为两个国家间的互动会对第三国产生一个有利的和不利的结果,这个结果会改变总体看法和整个三方的互动结构模式。对于菲律宾作为一个小国如何与两个大国互动,大国间关系也是独立变量。因此,有不同的互动模式存在。首先,是“直接/正面互动”,意思是国家间仅有政府与政府的关系;其次是“间接/侧面互动”,意味着一种通过其他体系行为体发生的互动,比如以国家为成员的政府间组织(例如APEC, ASEAN, ARF)。最后是“秩序和偏好(OP)互动”,它指的是一个国家如何对其诉求的秩序或权力利益进行排序。第四种可能的互动是“排除异者互动”。两个国家根据他们自己共同或战略利益选择达成一致和安排。因此偶然而并非故意地排除另一个利益不在此的国家。第五种互动形式是“中心偏好(PP)互动”。它是这样一种情势,一个国家通过均势和捭阖,相对于其他两国获取最为有利的位置。诚如在其外交政策实践中所体现的,菲律宾与美国与中国的关系对其外交至关重要,也要以实体身份适应东盟和联合国并负起制定发现和参与政策的责任。菲律宾作为国家,在其与美国和中国的关系中,通过东盟和亚太经合组织间接地和有扩大地发展正面的外交纽带关系。经济上,两个大国都是菲律宾最大的贸易伙伴,由于自由贸易协定和特惠贸易协定也是最大的利益方。在政治方面,菲律宾与两个大国有重要的合作,却仅与美国有着相似的政治价值和体系。菲律宾与中国通过双边官员交流和政府间组织的方式有着合作。在安全方面,菲律宾与美国有共同防御条约。这个依赖性条约包括传统和非传统安全的关注点。由于不平等、协议规定违宪和不平衡的关系,同盟一度受到质疑。中国方面,有关于南中国海的领土争端。双边和东盟方面都在关注这个问题。在社会文化方面,由于都是亚洲国家,菲律宾深受中国儒家文化和价值体系影响,其中社会和孝道方面有广泛的共鸣,而美国对菲律宾有西方

关键词：影响角度多维外溢三边互动框架准战略三角阴影外交

Effects of Type and Content of Mineral Fillers on Engineering Properties of Asphalt Mastic

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Effects of Type and Content of Mineral Fillers on Engineerin...

作者： aaron d.Mwanza 湖南大学

学位级别：硕士

沥青胶浆由沥青结合料和矿物填料组成，是用于道路铺筑的沥青混合料的重要组成部分。然而，向沥青结合料中添加不同种类及含量的矿物填料将造成沥青胶浆工程性质的显著改变。本文就将研究添加不同种类及含量的矿物填料对沥青胶浆工程性... 详细信息

沥青胶浆由沥青结合料和矿物填料组成，是用于道路铺筑的沥青混合料的重要组成部分。然而，向沥青结合料中添加不同种类及含量的矿物填料将造成沥青胶浆工程性质的显著改变。本文就将研究添加不同种类及含量的矿物填料对沥青胶浆工程性质的影响。在实验室中，利用石灰石、波特兰水泥和消石灰三种不同的矿物填料分别作为70号石油沥青结合料的添加剂，按0.3的比例增加，制成矿粉结合料比从0到1.5的沥青胶浆试件进行试验。此外，将石灰石作为SBS I-d沥青结合料的添加剂按同样的方式制成胶浆试件用于试验。通过试验，得到了沥青胶浆针入度、针入度指数、软化点、延度及粘度等工程性质对应于不同添加剂种类及含量的函数关系。试验结果表明，对于研究中使用的所有矿物填料，沥青胶浆的针入度均随填料含量的增加而降低。25℃时，增加矿粉结合料比从0到1.2，对于70号石油沥青结合料，添加熟石灰制成的沥青胶浆针入度降低约50dmm(dmm=0.1mm)，添加石灰石和波特兰水泥制成的沥青胶浆针入度降低约25dmm，前者比后者变化显著，对于添加了石灰石的SBS I-d沥青结合料，针入度降低约25dmm。对于70号石油沥青胶浆，添加熟石灰和波特兰水泥时其针入度指数随填料含量的增加而增加，直到达到最佳矿粉结合料比，但添加石灰石时结果相反。对于添加石灰石的SBS I-d沥青胶浆，其针入度指数同样表现一最佳矿粉结合料比，该比值高于其他胶浆的最佳矿粉结合料比。对于所有胶浆，其软化点和粘度随填料含量的增加而增加，而其延度均随填料含量的增加而降低。在同等矿粉结合料比的情况下，添加熟石灰后所有胶浆工程性质的改变均比添加其他种类的填料显著。然而，矿粉结合料比为1.5时，由于添加熟石灰后试件太硬无法拌和，因此沥青胶浆的工程性质无法测试。

关键词：沥青结合料矿物填料沥青胶浆矿粉结合料比工程性质

Multi-Material ALE with AMR for Modeling Hot Plasmas and Cold Fragmenting Materials

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Plasma Science and Technology 2015年第2期17卷 117-128页

作者： Alice KONIGES Nathan MASTERS aaron FISHER david EdER Wangyi LIU Robert ANdERSON david BENSON Andrea BERTOZZI Lawrence Berkeley National Laboratory Lawrence Livermore National Laboratory Jacobs School of Engineering 9500 Gilman Dr.UCSDLa JollaCA 92093USA department of Mathematics 520 Portola PlazaUCLALos AngelesCA 90095USA

We have developed a new 3d multi-physics multi-material code, ALE-AMR, which combines Arbitrary Lagrangian Eulerian （ALE） hydrodynamics with Adaptive Mesh Refinement （AMR） to connect the continuum to the microstructural regimes. The code is unique in its ability to model hot radiating plasmas and cold fragmenting solids. New numerical techniques were developed for many of the physics packages to work efficiently on a dynamically moving and adapting mesh. We use interface reconstruction based on volume fractions of the material components within mixed zones and reconstruct interfaces as needed. This interface reconstruction model is also used for void coalescence and fragmentation. A flexible strength/failure framework allows for pluggable material models, which may require material history arrays to determine the level of accumulated damage or the evolving yield stress in J2 plasticity models. For some applications laser rays are propagating through a virtual composite mesh consisting of the finest resolution representation of the modeled space. A new 2nd order accurate diffusion solver has been implemented for the thermal conduction and radiation transport packages. One application area is the modeling of laser/target effects including debris/shrapnel generation. Other application areas include warm dense matter, EUV lithography, and material wall interactions for fusion devices.

关键词： multi-physics simulations arbitrary lagrangian eulerian hydrodynamics,adaptive mesh refinement fragmentation laser ray tracing NIF

Effects of Various Light-Emitting diode(LEd)Wavelengths on the Growth of Scenedesmus Obliquus Fachb-12 and Accumulation of Astaxanthin

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Phyton-International Journal of Experimental Botany 2019年第3期88卷 335-348页

作者： Huabing Xu Xiaojuan Liu Zhiping Mei Jinchun Lin Stephan aaron Hong du Guangdong Provincial Key Laboratory of Marine Biotechnology and STU-UNIVPM Joint Algal Research Center College of SciencesShantou UniversityShantou515063China ONCE Inc.1525523rd Ave N Plymouth MN 55447USA

Given the central role of light in the algal photosynthesis,respiration,cell division,growth and the accumulation of value products,the effects of light-emitting diodes(LEds)light wavelengths(blue,white,red and green)were studied in Scenedesmus ***,residual nutrient amount,soluble protein,astaxanthin and reactive oxygen species,superoxide dismutase(SOd),catalase(CAT)and peroxidase(POd)activity were analyzed to determine the effects of different monochromatic light wavelengths via biochemical *** results showed that blue light wavelength is the optimal light wavelength for phosphorus removal efficiency and the accumulation of biomass and astaxanthin in ***,high reactive oxygen species content under the blue light might induce the accumulation of *** high activity of SOd,CAT and POd might participate in clearing the reactive oxygen species to facilitate the growth of ***,we found mixed blue/green lights treatment is the most appropriate mixture for the nitrogen *** the blue light treatment,high light intensity and 18L:6d light cycle is the best condition for biomass and astaxanthin *** nitrogen/phosphorus removal efficiency was observed under a 24L:0d light *** results might provide a foundational data for the optimizing the productivity of high-value metabolites and treatment of wastewater.

关键词： Light-emitting diodes wavelength cell density nutrient removal efficiency astaxanthin

GANana:Unsupervised domain Adaptation for Volumetric Regression of Fruit

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Plant Phenomics 2021年第1期3卷 326-336页

作者： Zane K.J.Hartley aaron S.Jackson Michael Pound Andrew P.French School of Computer Science University of NottinghamNG71BBUK School of Biosciences University of NottinghamLE125RDUK

3d reconstruction of fruit is important as a key component of fruit grading and an important part of many size estimation *** many computer vision challenges,the 3d reconstruction task suffers from a lack of readily available training data in most domains,with methods typically depending on large datasets of high-quality image-model *** this paper,we propose an unsupervised domain-adaptation approach to 3d reconstruction where labelled images only exist in our source synthetic domain,and training is supplemented with different unlabelled datasets from the target real *** approach the problem of 3d reconstruction using volumetric regression and produce a training set of 25,000 pairs of images and volumes using hand-crafted 3d models of bananas rendered in a 3d modelling environment(Blender).Each image is then enhanced by a GAN to more closely match the domain of photographs of real images by introducing a volumetric consistency loss,improving performance of 3d reconstruction on real *** solution harnesses the cost benefits of synthetic data while still maintaining good performance on real world *** focus this work on the task of 3d banana reconstruction from a single image,representing a common task in plant phenotyping,but this approach is general and may be adapted to any 3d reconstruction task including other plant species and organs.

关键词： image render adapted