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MEMS-actuated metasurface Alvarez lens

Microsystems & Nanoengineering 2020年第1期6卷 334-344页

作者： Zheyi Han Shane Colburn Arka Majumdar karl F.Bohringer Department of Electrical and Computer Engineering University of WashingtonSeattleWashington 98195USA Institute for Nano-Engineered Systems University of WashingtonSeattleWashington 98195USA Department of Physics University of WashingtonSeattleWashington 98195USA Department of Bioengineering University of WashingtonSeattleWashington 98195USA

Miniature lenses with a tunable focus are essential components for many modern applications involving compact optical *** several tunable lenses have been reported with various tuning mechanisms,they often face challenges with respect to power consumption,tuning speed,fabrication cost,or production *** this work,we have adapted the mechanism of an Alvarez lens–a varifocal composite lens in which lateral shifts of two optical elements with cubic phase surfaces give rise to a change in the optical power–to construct a miniature,microelectromechanical system(MEMS)-actuated metasurface Alvarez *** based on an electrostatic MEMS generates fast and controllable actuation with low power *** utilization of metasurfaces–ultrathin and subwavelength-patterned diffractive optics–as optical elements greatly reduces the device volume compared to systems using conventional freeform *** entire MEMS Alvarez metalens is fully compatible with modern semiconductor fabrication technologies,granting it the potential to be mass-produced at a low unit *** the reported prototype operating at 1550 nm wavelength,a total uniaxial displacement of 6.3µm was achieved in the Alvarez metalens with a direct-current(DC)voltage application up to 20V,which modulated the focal position within a total tuning range of 68µm,producing more than an order of magnitude change in the focal length and a 1460-diopter change in the optical *** MEMS Alvarez metalens has a robust design that can potentially generate a much larger tuning range without substantially increasing the device volume or energy consumption,making it desirable for a wide range of imaging and display applications.

关键词： electrostatic optics adapted

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The records of coastline changes reflected by mangroves on the Sunda Shelf since the last 40ka

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Chinese Science Bulletin 2008年第13期53卷 2069-2076页

作者： WANG XiaoMei SUN XiangJun WANG PinXian karl Stattegger Research Institute of Petroleum Exploration and Development Beijing 100083 China Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Institute of Botany Chinese Academy of Sciences Beijing 100093 China Institute of Geosciences University of Kiel Olshausenstrasse 40 Kiel 24118 Germany

This paper presents a 40000-year-long high-resolution mangrove record from sediments of Core 18300,18302 and 18323 on the continental shelf of the southern South China Sea and reconstructs the coast-line changes on Sunda Shelf since the last 40000 years. In the period Marine Isotope 3,the old Sunda Shelf had low sea level,and it was partly exposed. Flourishing vegetations grew on the exposed old land. Mangroves developed along the coastline. On the Last Glacial Maximum,the sea level dropped greatly,coastline moved from inner shelf to outer shelf,the Old Sunda Land exposed further,and the lowering sea level induced the gradual disappearing of mangroves from the inner Sunda Shelf to the outer Sunda Shelf. And pioneer vegetation ferns covered the broadly exposed old land immediately. At the time of the last Deglaciation,sea level rose greatly,the coastline moved to the sea and the Sunda Shelf was drown again. Mangroves were emergent again from outer shelf to inner shelf and developed quickly.

关键词：红树同位素冰川海岸线

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The relationship between relative growth rate and whole-plant C:N:P stoichiometry in plant seedlings grown under nutrient-enriched conditions

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Journal of Plant Ecology 2011年第3期4卷 147-156页

作者： Youhong Peng karl J.Niklas Shucun Sun ECORES Lab Chengdu Institute of BiologyChinese Academy of Sciences9 Section 4 Renminnan RoadChengdu 610041China Department of Plant Biology Cornell UniversityIthacaNY 14850USA Department of Biology Nanjing UniversityNanjing 210093China

Aims Recent theories indicate that N is more in demand for plant growth than P;therefore,N concentration and N:C and N:P ratios are predicted to be positively correlated with relative growth rate(RGR)in plants under nutrient-enriched *** prediction was tested in this *** We examined the whole-plant concentrations of C,N and P and RGR,as well as the relationship between RGR and the concentrations and the ratios of N:C,P:C and N:P,for different harvest stages(the days after seed germination)of the seedlings of seven shrub species and four herbaceous species grown in N and P non-limiting *** relationships among plant size,nutrient concentrations and ratios were subsequently *** Findings RGR was positively correlated with N concentration and the ratios of N:PandN:C when the data were pooled for all species and for each shrub species,but not for individual herbaceous ***,the relationship between RGR and P concentration and P:C was not significantly correlated for either shrubs or *** variation of N among harvest stages and species was much greater than that of P,and the variation in N:P ratio was determined primarily by changes in N *** shrub species differed from the herbaceous species in their N and P concentrations,nutrient ratios and in intraspecific relationships between RGR and nutrient *** differences possibly reflect differences in the capacity for P storage and biomass allocation *** general,our data support recent theoretical predictions regarding the relationship between RGR and C:N:P stoichiometry,but they also show that species with different life forms differ in the relationships among RGR and C:N:P stoichimetries.

关键词： C:N:P stoichiometry RGR growth rate hypothesis life forms seedlings screening experiment

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Truffle-like fungi sporocarps in a eucalypt-dominated landscape: patterns in diversity and community structure

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Fungal Diversity 2013年第1期58卷 143-157页

作者： Melissa Danks Teresa Lebel karl Vernes Nigel Andrew Ecosystem Management University of New EnglandArmidaleNew South Wales 2351Australia National Herbarium of Victoria Royal Botanic Gardens MelbourneSouth YarraVictoria 3141Australia Centre for Behavioural and Physiological Ecology ZoologyUniversity of New EnglandArmidaleNew South Wales 2351Australia

Truffle-like fungi are highly diverse yet poorly known in *** assess the species richness,biomass,and community assemblages of truffle-like fungi in different habitats we sampled sporocarps of truffle-like fungi in three eucalypt-dominated forest types(grassy woodland,wet sclerophyll forest,and dry sclerophyll forest)once in summer and once in winter,at two sites(Mount Kaputar and New England)in northern New South Wales,*** hundred and eighteen species in 35 genera were collected;over half(51.7%)of the species were *** woodland and wet forest communities had greater species richness and a lower standing crop than dry forest *** richness and standing crop was greater in winter than in ***,species from the family Russulaceae,and the genera Dermocybe,Descomyces,and Hysterangium were *** composition varied among forest types and each forest type exhibited a suite of unique and common species,although much variation was *** in community structure was associated with some habitat attributes;at Mount Kaputar,woody plant species richness,canopy cover,litter depth,soil phosphorous,and elevation helped explain the sporocarp communities of different forest types,while at New England,woody plant species richness,rainfall,topographic aspect,soil texture,and soil nitrogen helped explain *** work contributes to knowledge of trufflelike fungal diversity,the factors affecting sporocarp distribution across landscapes,and the availability of sporocarps as a food resource for mycophagous *** understanding of fungal diversity and mammal-fungal interactions also has important implications for managing forest biodiversity.

关键词： Basidiomycetes Biodiversity Forest ecology Fungal diversity Mycorrhizal fungi Sequestrate fungi

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Adjustable white-light emission from a photo-structured micro-OLED array

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Light(Science & Applications) 2016年第1期5卷 598-603页

作者： Simonas Krotkus Daniel Kasemann Simone Lenk karl Leo Sebastian Reineke dresden Integrated Center for Applied Physics and Photonic Materials(IAPP)and Institute for Applied Physics Technische Universität Dresden01062 DresdenGermany

White organic light-emitting diodes(OLEDs)are promising candidates for future solid-state lighting applications and backplane illumination in large-area *** very specific feature of OLEDs,which is currently gaining momentum,is that they can enable tunable white light *** feature is conventionally realized either through the vertical stacking of independent OLEDs emitting different colors or in lateral arrangement of *** vertical design is optically difficult to optimize and often results in efficiency compromises between the *** contrast,the lateral concept introduces severe area losses to dark regions between the subunits,which requires a significantly larger overall device area to achieve equal *** we demonstrate a color-tunable,two-color OLED device realized by side-by-side alignment of yellow and blue p-i-n OLEDs structured down to 20μm by a simple and up-scalable orthogonal photolithography *** layout eliminates the problems of conventional lateral approaches by utilizing all area for light *** corresponding emission of the photo-patterned two-unit OLED can be tuned over a wide range from yellow to white to blue *** independent control of the different units allows the desired overall spectrum to be set at any given brightness *** as a white light source,the microstructured OLED reaches a luminous efficacy of 13 lm W^(−1) at 1000 cd m^(−2) without an additional light outcoupling enhancement and reaches a color rendering index of 68 when operated near the color point ***,we demonstrate an improved device lifetime by means of size variation of the subunits.

关键词： color tuning hydrofluoroethers orthogonal photolithography orthogonal processing white organic light-emitting diodes

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Intelligent Manufacturing for the Process Industry driven by Industrial Artificial Intelligence

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Engineering 2021年第9期7卷 1224-1230页

作者： Tao Yang Xinlei Yi Shaowen Lu karl HJohansson Tianyou Chai State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China School of Electrical Engineering and Computer Science KTH Royal Institute of TechnologyStockholm 10044Sweden

Based on the analysis of the characteristics and operation status of the process industry,as well as the development of the global intelligent manufacturing industry,a new mode of intelligent manufacturing for the process industry,namely,deep integration of industrial artificial intelligence and the Industrial Internet with the process industry,is *** paper analyzes the development status of the existing three-tier structure of the process industry,which consists of the enterprise resource planning,the manufacturing execution system,and the process control system,and examines the decision-making,control,and operation management adopted by process *** on this analysis,it then describes the meaning of an intelligent manufacturing framework and presents a vision of an intelligent optimal decision-making system based on human–machine cooperation and an intelligent autonomous control ***,this paper analyzes the scientific challenges and key technologies that are crucial for the successful deployment of intelligent manufacturing in the process industry.

关键词： Industrial artificial intelligence Industrial Internet Intelligent manufacturing Process industry

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Characterization of mechanical properties for tubular materials based on hydraulic bulge test under axial feeding force

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Fundamental Research 2023年第4期3卷 592-601页

作者： Bin Zhang Benny Endelt karl Brian Nielsen Department of Materials and Production Aalborg UniversityAalborg 9220Denmark Engineering Teaching Practice Training Center Tiangong UniversityTianjin 300387China Research and Development Lab Vestas aircoil A/SLem 6940Denmark Department of Mechanical and Production Engineering Aarhus UniversityAarhus 8000Denmark

A T-shape tube hydraulic bulge test under axial feeding force is carried out to characterize the mechanical properties of EN AW 5049-O and 6060-O aluminium *** punch displacement,T-branch height and axial compressive force are recorded online during the *** intelligent inverse identification framework combining the finite element method and numerical optimization algorithm is developed to determine material parameters by fitting simulated results to the experimental data *** identified constitutive parameters using the inverse modelling technique are compared with those determined by the theoretical analysis and uniaxial tensile *** comparison shows that the predicted bulge height and punch force based on the material parameters obtained by the three methods are different and the inverse strategy produces the smallest gap between numerical and experimental *** is possible to conclude that the hydraulic bulge test can be applied to characterize the stress-strain curve of tubular materials at the large strain scope,and the automatic inverse framework is a more accurate post-processing procedure to identify material constitutive parameters compared with the classical analytical model.

关键词： Intelligent optimization Tubular material Parameter identification Hydraulic bulge test Constitutive model

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The 2/3 scaling of twig nitrogen to phosphorus in woody plants

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Forest Ecosystems 2022年第4期9卷 521-528页

作者： Zhiqiang Wang karl JNiklas Zeqing Ma Dechun Jiang Jianming Deng Sichuan Zoige Alpine Wetland Ecosystem National Observation and Research Station Southwest Minzu UniversityChengdu610041China Institute of Qinghai-Tibetan Plateau Southwest Minzu UniversityChengdu610041China Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNY14853USA Center for Forest Ecosystem Studies and Qianyanzhou Ecological Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China Chengdu Institute of Biology Chinese Academy of SciencesChengdu610041China State Key Laboratory of Grassland Agro-Ecosystem College of EcologyLanzhou UniversityLanzhou730000China

Background:Nitrogen(N)and phosphorus(P)are important elements for plant metabolism and ***fore,the quantification of the scaling relationship of N to P in plant organs can help us understand many fundamental ecological *** general scaling relationships between N and P in leaves and in fine roots have been *** compared to leaves and fine roots,however,little information is available on the N versus P scaling relationship in the stems of woody plants,especially for *** this study,a comprehensive dataset comprising 2,038 N=P paired observations for a total of 536 woody species was compiled and analyzed to determine whether a general scaling relationship ***:The global mean values of twig N and P concentrations and N:P ratios were 9.33 mg⋅g^(-1),1.12 mg⋅g^(-1) and 10.16,*** N and P concentrations and N:P ratios differed significantly within and across functional groups and *** all of the species,a uniform 0.67 scaling exponent of twig N to P was observed across different functional groups and biomes,i.e.,a 2/3-power scaling relationship was ***,this numerical value differed across different sites,albeit converging onto 0.67 with increasing sample *** total phosphorus was the largest contributor to the variation in the numerical value of the scaling ***:These results provide useful parameters for stoichiometric growth models,and advance our understanding of the mechanisms underlying plant nutrient *** study has potential implications in predicting responses of nutrient cycling in terrestrial ecosystem responses to changes in the environment.

关键词： Nitrogen Phosphorus Scaling exponents Twigs Woody plants

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Selective deletion of the soluble Colony-Stimulating Factor 1 isoform in vivo prevents estrogen-deficiency bone loss in mice

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Bone Research 2017年第4期5卷 367-374页

作者： Gang-Qing Yao Nancy Troiano Christine A Simpson karl L Insogna Department of Internal Medicine Yale University School of MedicineNew HavenUSA Department of Orthopaedics Yale University School of MedicineNew HavenUSA

Neutralizing CSF1 in vivo completely prevents ovariectomy （OVX）-induced bone loss in mice. There are two isoforms of CSF1, soluble （sCSF1）, and membrane-bound （mCSF1）, but their individual biological functions are unclear. It had been previously reported that mCSF1 knockout （K/O） and wild type （Wt） female mice experience the same degree of bone loss following OVX. In Wt mice the expression of sCSF1 was elevated fourfold in skeletal tissue following OVX while expression of mCSF1 was unchanged. To examine the role of sCSF1 in OVX-induced bone loss, mice were engineered in which sCSF1 was not expressed but expression of mCSF1 was unaffected （sCSF1 K/O）. Isoform-specific reverse transcription PCR confirmed the absence of transcripts for sCSF1 in bone tissue isolated from these animals and no circulating CSF1 was detected by ELISA. Surprisingly, there were no significant differences in bone mineral density （BMD） between sCSF1 K/O mice and Wt controls as assessed by dual-energy X-ray absorptiometry and micro-CT. However, one month after OVX, femoral, spinal and total BMD had declined by 11.2%, 8.9%, and 8.7% respectively in OVX-Wt animals as compared to Sham-OVX. In contrast OVX sCSF1 K/O mice showed changes of ＋0.1%, - 2.4%, and ＋2.3% at the same 3 sites compared to Sham-OVX sCSF1 K/O mice. These data indicate important non-redundant functions for the two isoforms of CSF1 and suggest that sCSF1, but not mCSF1, plays a key role in estrogen-deficiency bone loss.

关键词： CSF Selective deletion of the soluble Colony-Stimulating Factor 1 isoform in vivo prevents estrogen-deficiency bone loss in mice

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ADAPTIVE FINITE ELEMENT APPROXIMATION FOR A CLASS OF PARAMETER ESTIMATION PROBLEMS

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Journal of Computational Mathematics 2010年第5期28卷 645-675页

作者： karl Kunisch Wenbin Liu Yanzhen Chang Ningning Yan Ruo Li Department of Mathematics University of Graz Austria KBS University of Kent Canterbury CT2 7NF England LSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Department of Computational Mathematics Peking University China

In this paper, we study adaptive finite element discretisation schemes for a class of parameter estimation problem. We propose to efficient algorithms for the estimation problem use adaptive multi-meshes in developing We derive equivalent a posteriori error estimators for both the state and the control approximation, which particularly suit an adaptive multi-mesh finite element scheme. The error estimators are then implemented and tested with promising numerical results.

关键词： Parameter estimation Finite element approximation Adaptive finite elementmethods A posteriori error estimate.

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