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The 3-billion fossil question:How to automate classification of microfossils

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Artificial Intelligence in Geosciences

Artificial Intelligence in Geosciences 2024年第1期5卷 137-145页

作者： Iver Martinsen David Wade Benjamin Ricaud Fred Godtliebsen uit-the arctic university of norway TromsøNorway Equinor ASA StavangerNorway

Microfossil classification is an important discipline in subsurface exploration,for both oil&gas and Carbon Capture and Storage(CCS).The abundance and distribution of species found in sedimentary rocks provide valuable information about the age and depositional ***,the analysis is difficult and consuming,time-as it is based on manual work by human *** to automate this process face two key challenges:(1)the input data are very large-our dataset is projected to grow to 3 billion microfossils,and(2)there are not enough labeled data to use the standard procedure of training a deep learning *** propose an efficient pipeline for processing and grouping fossils by genus,or even species,from microscope slides using self-supervised *** we show how to efficiently extract crops from whole slide images by adapting previously trained object detection ***,we provide a comparison of a range of self-supervised learning methods to classify and identify microfossils from very few *** obtain excellent results with both convolutional neural networks and vision transformers fine-tuned by *** approach is fast and computationally light,providing a handy tool for geologists working with microfossils.

关键词： Self-supervised learning Palynology Deep learning Microfossils

Ship performance and navigation data compression and communication under autoencoder system architecture

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Journal of Ocean Engineering and Science 2018年第2期3卷 133-143页

作者： Lokukaluge P.Perera B.Mo uit The arctic university of norway TromsoNorway SINTEF Ocean TrondheimNorway

Modern vessels are designed to collect,store and communicate large quantities of ship performance and navigation information through complex onboard data handling *** data should be transferred to shore based data centers for further analysis and ***,the associated transfer cost in large-scale data sets is a major challenge for the shipping industry,*** same cost relates to the amount of data that are transferring through various communication networks(*** and wireless networks),*** vessels and shore based data ***,this study proposes to use an autoencoder system architecture(i.e.a deep learning approach)to compress ship performance and navigation parameters(*** the number of parameters)and transfer through the respective communication networks as reduced data *** data compression is done under the linear version of an autoencoder that consists of principal component analysis(PCA),where the respective principal components(PCs)represent the structure of the data *** compressed data set is expanded by the same data structure(*** autoencoder system architecture)at the respective data center requiring further analyses and storage.A data set of ship performance and navigation parameters in a selected vessel is analyzed(*** compression and expansion)through an autoencoder system architecture and the results are presented in this ***,the respective input and output values of the autoencoder are also compared as statistical distributions and sample number series to evaluate its performance.

关键词： Autoencoder Ship performance and navigation information Ship energy efficiency Data compression Data communication Principal component analysis

Ship speed power performance under relative wind profiles in relation to sensor fault detection

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Journal of Ocean Engineering and Science 2018年第4期3卷 355-366页

作者： Lokukaluge P.Perera B.Mo uit The arctic university of norway TromsoNorway SINTEF Ocean TrondheimNorway

Statistical data analysis and visualization approaches to identify ship speed power performance under relative wind(*** wind)profiles are considered in this *** performance and navigation data of a selected vessel are analyzed,where various data anomalies,*** related erroneous data conditions,are *** erroneous data conditions are investigated and several approaches to isolate such situations are also presented by considering appropriate data visualization ***,the cleaned data are used to derive various relationships among ship performance and navigation parameters that have been visualized in this study,*** results show that the wind profiles along ship routes can be used to evaluate vessel performance and navigation conditions by assuming the respective sea states relate to their wind ***,the results are useful to derive appropriate mathematical models that represent ship performance and navigation *** mathematical models can be used for weather routing type applications(*** planning),where the respective weather forecast can be used to derive optimal ship routes to improve vessel performance and reduce fuel *** study presents not only an overview of statistical data analysis of ship performance and navigation data but also the respective challenges in data anomalies(*** data intervals and sensor faults)due to onboard sensors and data handling ***,the respective solutions to such challenges in data quality have also been presented by considering data visualization approaches.

关键词： Speed power performance Data anomaly detection Sensor fault identification Weather routing Statistical data analysis Ship wind profile.

Sound waves in fluidized bed using CFD-DEM simulations

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Particuology 2018年第3期16卷 126-133页

作者： Hassan Abbas Khawaja Process and Gas Group Department of Engineering & Safety UiT-The Arctic University of Norway 9037 Langnes Tromso Norway

The speed of sound waves in a fluidized bed is investigated using CFD-DEM numerical simulations, Appro- priate initial and boundary conditions are applied to reproduce bed phenomena. The effect of varying the height of the bed is also studied. The results of the simulations matched those from the literature. The pressure and particle velocity profiles obtained feature oscillatory behavior to which functions （based on a damped standing wave） were fitted, enabling an explicit dependence on time and space variables to be established. These fitted functions were substituted into the linearized governing equations for the two-phase flow. These solutions enabled a new relationship to be derived for the speed of sound and damping in the system. The conclusion drawn is tbat the damping in the system is governed by the effective bulk viscosity of the solid phase, which arises from the particle viscosity.

关键词： Fluidized bed Sound waves Speed of sound Damping time CFD-DEM simulations

Chip-based multimodal super-resolution microscopy for histological investigations of cryopreserved tissue sections

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Light(Science & Applications) 2022年第3期11卷 35-51页

作者： Luis E.Villegas-Hernández Vishesh Dubey Mona Nystad Jean-Claude Tinguely David A.Coucheron Firehun T.Dullo Anish Priyadarshi Sebastian Acuña Azeem Ahmad JoséM.Mateos Gery Barmettler Urs Ziegler Åsa Birna Birgisdottir Aud-Malin Karlsson Hovd Kristin Andreassen Fenton Ganesh Acharya Krishna Agarwal Balpreet Singh Ahluwalia Department of Physics and Technology UiT The Arctic University of NorwayKlokkargårdsbakken N-9019TromsøNorway Department of Clinical Medicine Women’s Health and Perinatology Research GroupUiT The Arctic University of NorwayTromsøNorway Department of Obstetrics and Gynecology University Hospital of North NorwayTromsøNorway Center for Microscopy and Image Analysis University of ZurichZürichSwitzerland Division of Cardiothoracic and Respiratory Medicine University Hospital of North NorwayTromsøNorway Department of Clinical Medicine Clinical Cardiovascular Research GroupUiT The Arctic University of NorwayTromsøNorway Department of Medical Biology RNA and Molecular Pathology Research GroupUiT The Arctic University of NorwayTromsøNorway Division of Obstetrics and Gynecology Department of Clinical ScienceIntervention and TechnologyKarolinska InstituteStockholmSweden

Histology involves the observation of structural features in tissues using a *** diffraction-limited optical microscopes are commonly used in histological investigations,their resolving capabilities are insufficient to visualize details at subcellular *** a novel set of super-resolution optical microscopy techniques can fulfill the resolution demands in such cases,the system complexity,high operating cost,lack of multi-modality,and low-throughput imaging of these methods limit their wide adoption for histological *** this study,we introduce the photonic chip as a feasible high-throughput microscopy platform for super-resolution imaging of histological *** cryopreserved ultrathin tissue sections of human placenta,mouse kidney,pig heart,and zebrafish eye retina prepared by the Tokuyasu method,we demonstrate diverse imaging capabilities of the photonic chip including total internal reflection fluorescence microscopy,intensity fluctuation-based optical nanoscopy,single-molecule localization microscopy,and correlative light-electron *** results validate the photonic chip as a feasible imaging platform for tissue sections and pave the way for the adoption of super-resolution high-throughput multimodal analysis of cryopreserved tissue samples both in research and clinical settings.

关键词： resolution modal feasible

Label-free superior contrast with c-band ultra-violet extinction microscopy

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Light(Science & Applications) 2023年第3期12卷 435-445页

作者： Florian Ströhl Deanna L.Wolfson Ida S.Opstad Daniel H.Hansen Hong Mao Balpreet S.Ahluwalia Department of Physics and Technology UiT The Arctic University of NorwayTromsøNorway Department of Clinical Science Intervention and TechnologyKarolinska InstituteStockholmSweden

In 1934,Frits Zernike demonstrated that it is possible to exploit the sample’s refractive index to obtain superior contrast images of biological *** refractive index contrast of a cell surrounded by media yields a change in the phase and intensity of the transmitted light *** change can be due to either scattering or absorption caused by the *** cells are transparent at visible wavelengths,which means the imaginary component of their complex refractive index,also known as extinction coefficient k,is close to ***,we explore the use of c-band ultra-violet(UVC)light for high-contrast high-resolution label-free microscopy,as k is naturally substantially higher in the UVC than at visible *** differential phase contrast illumination and associated processing,we achieve a 7-to 300-fold improvement in contrast compared to visible-wavelength and UVA differential interference contrast microscopy or holotomography,and quantify the extinction coefficient distribution within liver sinusoidal endothelial *** a resolution down to 215 nm,we are,for the first time in a far-field label-free method,able to image individual fenestrations within their sieve plates which normally requires electron or fluorescence superresolution *** illumination also matches the excitation peak of intrinsically fluorescent proteins and amino acids and thus allows us to utilize autofluorescence as an independent imaging modality on the same setup.

关键词： wave. extinction violet

Challenges Associated with Creeping Disasters in Disaster Risk Science and Practice:Considering Disaster Onset Dynamics

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International Journal of Disaster Risk Science 2022年第1期13卷 1-11页

作者： Reidar Staupe-Delgado Olivier Rubin Department of Social Sciences and Business.Roskilde university 4000 RoskildeDenmark Department of Technology and Safety UiT The Arctic University of Norway9037 TromsONorway

In this article,we set out to reconcile a general conceptualization of disaster temporalities by drawing on the epitome example of a creeping disaster,namely *** argument is driven by the recognition that slowly manifesting disaster impacts pose distinct challenges for decision makers and researchers while there is a tendency for the disaster literature to overlook the role of disaster onset *** specifically and as a starting point,we identify four key themes that merit particular attention when dealing with creeping disasters:(1)our understanding of disaster as a phenomenon;(2)measurement and operationalization;(3)early warning and response;and(4)disaster management and *** integrating conceptual discussions of disaster with famine scholarship—a phenomenon often excluded from mainstream disaster research—this article provides fresh perspectives on disaster science as well as a number of implications for how we think about disaster risk reduction.

关键词： Disaster response Early warning Famine disasters Slow-onset disasters

Extraordinary evanescent field confinement waveguide sensor for mid-infrared trace gas spectroscopy

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Light(Science & Applications) 2021年第2期10卷 147-153页

作者： Marek Vlk Anurup Datta Sebastián Alberti Henock Demessie Yallew Vinita Mittal Ganapathy Senthil Murugan Jána Jagerská Department of Physics and Technology UiT The Arctic University of NorwayNO-9037 TromsøNorway Optoelectronics Research Centre University of SouthamptonSouthampton S0171BJUK

Nanophotonic waveguides are at the core of a great variety of optical *** structures confine light along defined paths on photonic chips and provide light-matter interaction via an evanescent ***,waveguides still lag behind free-space optics for sensitivity-critical applications such as trace gas *** optical pathlengths,low interaction strengths,and spurious etalon fringes in spectral transmission are among the main reasons why on-chip gas sensing is still in its *** this work,we report on a mid-infrared integrated waveguide sensor that successfully addresses these *** sensor operates with a 107%evanescent field confinement factor in air,which not only matches but also outperforms free-space beams in terms of the per-length optical ***,negligible facet reflections result in a flat spectral background and record-low absorbance noise that can finally compete with free-space *** sensor performance was validated at 2.566μm,which showed a 7 ppm detection limit for acetylene with only a 2 cm long waveguide.

关键词： waveguide ordinary field

Carnobacteria in fish

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Aquaculture and Fisheries 2024年第2期9卷 193-205页

作者： Einar Ring Norwegian College of Fishery Science Faculty of BioscienceFisheries and EconomicsUiT The Arctic University of NorwayTromsø9010Norway

Carnobacterium is a genus of Gram-positive bacteria,within family Carnobacteriaceae,and they are catalase-and oxidase-negative,non-sporing bacteria with properties such as CO_(2)and L(+)-lactic acid production from glucose,but they are not able to grow on acetate *** are ubiquitous lactic acid bacteria and have been isolated from both cold and temperate environments,and they are identified as components of the microbiota in the gastrointestinal(GI)tract of salmonids and several other fish species of which Carnobacterium(piscicola)maltaromaticum,Carnobacterium mobile,Carnobacterium divergens,Carnobacterium alterfunitum,and Carnobacterium inhibens are *** the last two decades several studies have revealed that carnobacteria can act as probiotics to promote health benefits of fish,as well as they in ex vivo studies to some extent can out-compete *** addition to beneficial effects,information is available that some carnobacteria species causing fish *** aim of the present review is to present an updated overview of Carnobacterium in fish,with focus on their presence in the GI tract,their use as probiotic supplement and general information on pathogenic carnobacteria.

关键词： Carnobacterium Gastrointestinal tract Probiotics Fish health Pathogenic