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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

One decade(2011–2020)of European agricultural water stress monitoring by MSG-SEVIRI:workflow implementation on the Virtual Earth Laboratory(VLab)platform

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International Journal of Digital Earth 2022年第1期15卷 730-747页

作者： Bagher Bayat Carsten Montzka alexander Graf Gregory Giuliani Mattia Santoro Harry Vereecken Institute of Bio-and Geosciences:Agrosphere (IBG-3) Forschungszentrum Jülich GmbHJülichGermany Institute for Environmental Sciences EnviroSPACE labUniversity of GenevaGenevaSwitzerland Institute of Atmospheric Pollution Research National Research Council of Italy (CNR)Sesto FiorentinoItaly

Cloud computing facilities can provide crucial computing support for processing the time series of satellite data and exploiting their spatio-temporal information ***,dedicated efforts are still required to develop workflows,executable on cloud-based platforms,for ingesting the satellite data,performing the targeted processes,and generating the desired *** this study,an operational workflow is proposed,based on monthly Evaporative Stress Index(ESI)anomaly,and implemented in cloud-based online Virtual Earth Laboratory(VLab)platform,as a demonstration,to monitor European agricultural water *** this end,daily time-series of actual and reference evapotranspiration(ETa and ET0),from the Spinning Enhanced Visible and Infrared Imager(SEVIRI)sensor,were used to execute the proposed workflow successfully on *** execution of the workflow resulted in obtaining one decade(2011–2020)of European monthly agricultural water stress maps at 0.04˚spatial resolution and corresponding stress reports for each *** support open science,all the workflow outputs are stored in GeoServer,documented in GeoNetwork,and made available through *** enables creating a dashboard for better visualization of the results for *** results from this study demonstrate the capability of VLab platform for water stress detection from time series of SEVIRI-ET data.

关键词： ET SEVIRI ESI water stress workflow Europe VLab demonstration

Vertical power flow forecast with LSTMs using regular training updatestrategies

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能源与人工智能(英文) 2022年第2期8卷 92-99页

作者： Katharina Brauns Christoph Scholz alexander Schultz AndréBaier Dominik Jost Fraunhofer IEE Königstor 5934119 KasselGermany

The strong growth of renewable energy sources as well as the increasing amount of volatile energy consumptionis leading to major challenges in the electrical grid. In order to ensure safety and reliability in the electricitygrid, a high quality of power flow forecasts for the next few hours are needed. In this paper we investigateforecasts of the vertical power flow at transformer between the medium and high voltage grid. Forecastingthe vertical power flow is challenging due to constantly changing characteristics of the power flow at thetransformer. We present a novel approach to deal with these challenges. For the multi step time series forecastsa Long-Short Term Memory (LSTM) is used. In our presented approach an update process where the model isretrained regularly is investigated and compared to baseline models. The model is retrained as soon as asufficient amount of new measurements are available. We show that this retraining mostly captures changesin the characteristic of the transformer that the model has not yet seen in the past and therefore cannot bepredicted by the model without an update process. To give more weight to recent data, we examined differentstrategies in terms of the number of epochs and the learning rate. We show that our new approach significantlyoutperforms the investigated baseline models. On average, we achieved an improvement of about 8% with theregular update process compared to the approach without update process.

关键词： Vertical power flow Forecasting LSTM

Safe operation of online learning data driven model predictive control of building energy systems

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Energy and AI 2023年第4期14卷 536-549页

作者： Phillip Stoffel Patrick Henkel Martin Ratz alexander Kumpel Dirk Muller RWTH Aachen University E.ON Energy Research CenterInstitute for Energy Efficient Buildings and Indoor ClimateMathieustraße 10Aachen52074Germany

Model predictive control is a promising approach to reduce the CO 2 emissions in the building ***,the vast modeling effort hampers the widescale practical ***,data-driven process models,like artificial neural networks,are well-suited to automatize the ***,the underlying data set strongly determines the quality and reliability of artificial neural *** general,the validity domain of a machine learning model is limited to the data that was used to train *** based on system states outside that domain,so-called extrapolations,are unreliable and can negatively influence the control *** present a safe operation approach combined with online learning to deal with extrapolation in data-driven model predictive ***,the k-nearest neighbor algorithm is used to detect extrapolation to switch to a robust fallback *** continuously retraining the artificial neural networks during operation,we successively increase the validity domain of the artificial neural networks and the control *** apply the approach to control a building energy system provided by the BOPTEST *** compare controllers based on two data sets,one with extensive system excitation and one with baseline *** system is controlled to a fixed temperature set point in baseline ***,the artificial neural networks trained on this data set tend to extrapolate in other operating *** show that safe operation in combination with online learning significantly improves performance.

关键词： Data-driven model predictive control Online learning Novelty detection Artificial neural networks Building energy systems

In situ Lu–Hf phosphate geochronology:Progress towards a new tool for space exploration

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Geoscience Frontiers 2022年第3期13卷 164-167页

作者： Stijn Glorie Thomas Burke Martin Hand alexander Simpson Sarah Gilbert Benjamin Wade Department of Earth Sciences The University of AdelaideSA 5005 AdelaideAustralia Adelade Microscopy The University of AdelaideSA 5005 AdelaideAustralia

Geochronology is fundamental to understanding planetary ***,as space exploration continues to expand,traditional dating methods,involving complex laboratory processes,are generally not realistic for unmanned space ***-style planetary exploration missions require dating methods that can(1)rapidly resolve age information on small samples,(2)be applied to minerals common in mafic rocks,and(3)be based on technologies that could be installed on future rover *** demonstrate the application of rapid in situ microanalytical Lu–Hf phosphate geochronology using samples of pallasite meteorites,which are representative examples of the deep interiors of differentiated planetoids that are generally difficult to *** pallasites were dated by laser ablation tandem mass-spectrometry(LA-ICP-MS/MS),demonstrating a rapid novel method for exploring planetary *** formation ages for individual pallasites agree with traditional methods and have<2%uncertainty,opening an avenue of opportunity for remote micro-analytical space exploration.

关键词： Pallasite meteorites Lu-Hf geochronology Laser ablation tandem mass-spectrometry Micro-analytical planetary exploration

Clinical view of gynecologic intraoperative frozen section diagnosis

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Gynecology and Obstetrics Clinical Medicine 2022年第1期2卷 6-8页

作者： alexander B.Olawaiye Chengquan Zhao Deporoment of Obsteprics and Gynecolagy Universiy of Piusbugh Medical CenterPinsburghPA16066USA Deparoment of Patholgy Uriversity of Piusbugh Medical CenterPitsbughPA16066USA

Intraoperative consultation includes gross evaluation and frozen section,whitch is an integral component of surgical oncology for many ***,it allows appropriate surgical procedures to be ***,it can potentially protect the patient from a second ***,it helps towards counselling of paients and their family members and lasty,it faclilitates early management *** of frozen section is justified by the reported sensi dvity,specificity,positive and negativwe predictive values all of which are as high as 90-100%in some *** is very impor tant for gynecologists to have good communication with pathologi sts,especially for cass with an indeterminate,frozen *** with the pathologist can help the gynecologist understand the diagnostic dilemma and the differential diagnosis,which can help them make best surgical decisions.

关键词： Gynecology Intraoperative Pathology

Engineering osteoarthritic cartilage model through differentiating senescent human mesenchymal stem cells for testing disease-modifying drugs

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Science China(Life Sciences) 2022年第2期65卷 309-327页

作者： Ning Wang Yuchen He Silvia Liu Meagan J.Makarcyzk Guanghua Lei alexander Chang Peter G alexander Tingjun Hao Anne-Marie Padget Nuria de Pedro Tsapekos Menelaos Hang Lin Department of Orthopaedic Surgery University of Pittsburgh School of MedicinePittsburgh PA 15219USA Department of Orthopedic Surgery Xiangya HospitalCentral South UniversityChangsha 410008China Department of Pathology University of Pittsburgh School of MedicinePittsburgh PA 15219USA Department of Bioengineering University of Pittsburgh Swanson School of EngineeringPittsburgh PA 15219USA Department of Bioinformatics University of Pittsburgh School of MedicinePittsburgh PA 15219USA McGowan Institute for Regenerative Medicine University of Pittsburgh School of MedicinePittsburgh PA 15219USA Department of Biology University of Pittsburgh Dietrich School of Arts and SciencePittsburgh PA 15219USA Department of Research B2B Life Length SLMadrid 28010Spain Xiangya Third Hospital Central South UniversityChangsha 410013China

Significant cellular senescence has been observed in cartilage harvested from patients with osteoarthritis(OA).In this study,we aim to develop a senescence-relevant OA-like cartilage model for developing disease-modifying OA drugs(DMOADs).Spe-cifically,human bone marrow-derived mesenchymal stromal cells(MSCs)were expanded in vitro up to passage 10(P10-MSCs).Following their senescent phenotype formation,P10-MSCs were subjected to pellet culture in chondrogenic *** from qRT-PCR,histology,and immunostaining indicated that cartilage generated from P10-MSCs displayed both senescent and OA-like phenotypes without using other OA-inducing agents,when compared to that from normal passage 4(P4)-***,the same gene expression differences observed between P4-MSCs and P10-MSC-derived cartilage tissues were also observed between the preserved and damaged OA cartilage regions taken from human samples,as demonstrated by RNA sequencing data and other analysis ***,the utility of this senescence-initiated OA-like cartilage model in drug development was assessed by testing several potential DMOADs and *** results suggest that pre-existing cellular senescence can induce the generation of OA-like changes in *** P4-and P10-MSCs derived cartilage models also represent a novel platform for predicting the efficacy and toxicity of potential DMOADs on both preserved and damaged cartilage in humans.

关键词： osteoarthritis MSC senescence cartilage tissue engineering disease-modifying OA drug senolytic

A modified isooctane-based DNA extraction method from crude oil

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mLife 2023年第3期2卷 328-338页

作者： Armando Alibrandi Rolando Primio alexander Bartholomäus Jens Kallmeyer GFZ German Research Centre for Geoscience Section GeomicrobiologyPotsdamGermany Aker BP LysakerNorway

Microbes from oil reservoirs shape petroleum composition through processes such as biodegradation or *** processes are considered economically detrimental and might pose health and safety *** is therefore crucial to understand the composition of a reservoir's microbial community and its metabolic ***,such analyses are hindered by difficulties in extracting DNA from such complex fluids as crude ***,we present a novel DNA extraction method from oils with a wide American Petroleum Institute(API)gravity(density)*** investigated the ability to extract cells from oils with different solvents and surfactants,the latter both nonionic and ***,we evaluated three DNA extraction ***,the best DNA yields and the highest number of 16S rRNA reads were achieved with isooctane as a solvent,followed by an ionic surfactant treatment using sodium dodecyl sulfate and DNA extraction using the PowerSoil Pro Kit(Qiagen).The final method was then applied to various oils from oil reservoirs collected in aseptic *** the expected low cell density of 10^(1)–10^(3)cells/ml,the new method yielded reliable results,with average 16S rRNA sequencing reads in the order of 41431(±8860)per ***,halophilic,and anaerobic taxa,which are most likely to be indigenous to the oil reservoir,were found in all *** gravity and DNA yield,despite the sufficient DNA obtained,did not show a correlation.

关键词： crude oil DNA extraction method oil reservoir microbiome

Viscosity of slags from the joint smelting of oxidized nickel and sulfide copper ores

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Transactions of Nonferrous Metals Society of China 2023年

作者： alexander KLYUSHNIKOV Svetlana SERGEEVA Roza GULYAEVA alexander VUSIKHIS Lyudmila UDOEVA Stanislav TYUSHNYAKOV Laboratory of Non-Ferrous Metals Pyrometallurgy， Department of Non-Ferrous Metals， Institute of Metallurgy of the Ural Branch of the Russian Academy of Sciences 2. Laboratory of Rare Refractory Metals， Department of Non-Ferrous Metals， Institute of Metallurgy of the Ural Branch of the Russian Academy of Sciences

The work is devoted to the viscosity determination of molten slags from the joint smelting of oxidized nickel and sulfide copper ores. The model slags were synthesized close in composition and structure to real samples， and limiting the investigated composition range: iron-containing slag (8.9 wt.% CaO， 11.8 MgO， 12.5 Al2O3， 47.4 SiO2， 13.3 FeO， 5.0 Fe2O3) and iron-free slag formed by removing iron oxides from the iron-containing slag (12.5 wt.% CaO， 16.0 MgO， 9.4 Al2O3， 58.3 SiO2). The experimental (vibrational method) viscosity values for iron-containing (1550–1300 ℃) and iron-free (1550–1400 ℃) model slags were 3.1–23.3 and 12.8–45.5 dPa·s， respectively. Viscosity estimation by the Kalmanovitch–Frank model showed a discrepancy with the experimental data for iron-containing slag. Regression analysis (by Weimann–Frenkel–Urbain formalism) of the experimental data was carried out， and original empirical models were proposed to predict the primary model slags viscosity in the considered temperature range. Reducing the basicity from 0.7 (iron-containing slag) to 0.6 (iron-free slag) increased viscous flow activation energy from 204 to 236 kJ·mol–1. To maintain optimal slag viscosity， joint smelting of oxidized nickel and sulfide copper ores should be carried out at a temperature not lower than 1400 ℃.

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Multi-agent reinforcement learning for edge information sharing in vehicular networks

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Digital Communications and Networks 2022年第3期8卷 267-277页

作者： Ruyan Wang Xue Jiang Yujie Zhou Zhidu Li Dapeng Wu Tong Tang alexander Fedotov Vladimir Badenko School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China Advanced Network and Intelligent Connection Technology Key Laboratory of Chongqing Education Commission of China Chongqing400065China Key Laboratory of Ubiquitous Sensing and Networking in Chongqing Chongqing400065China Peter the Great St.Petersburg Polytechnic University Polytechnicheskaya29St.Petersburg195251Russia

To guarantee the heterogeneous delay requirements of the diverse vehicular services,it is necessary to design a full cooperative policy for both Vehicle to Infrastructure(V2I)and Vehicle to Vehicle(V2V)*** paper investigates the reduction of the delay in edge information sharing for V2V links while satisfying the delay requirements of the V2I ***,a mean delay minimization problem and a maximum individual delay minimization problem are formulated to improve the global network performance and ensure the fairness of a single user,respectively.A multi-agent reinforcement learning framework is designed to solve these two problems,where a new reward function is proposed to evaluate the utilities of the two optimization objectives in a unified ***,a proximal policy optimization approach is proposed to enable each V2V user to learn its policy using the shared global network *** effectiveness of the proposed approach is finally validated by comparing the obtained results with those of the other baseline approaches through extensive simulation experiments.

关键词： Vehicular networks Edge information sharing Delay guarantee Multi-agent reinforcement learning Proximal policy optimization