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Non-destructive silkworm pupa gender classification with X-ray images using ensemble learning

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Artificial Intelligence in Agriculture 2022年第1期6卷 100-110页

作者： Sania thomas Jyothi thomas Department of Computer Science and Engineering Christ(Deemed to be University)BangaloreIndia

Sericulture is the process of cultivating silkworms for the production of silk.High-quality production of silk without mixing with low quality is a great challenge faced in the silk production centers.One of the possibilities to overcome this issue is by separating male and female cocoons before extracting silk fibers from the cocoons as male cocoon silk fibers are finer than females.This study proposes a method for the classification of male and female cocoons with the help of X-ray images without destructing the cocoon.The study used popular single hybrid varieties FC1 and FC2 mulberry silkworm cocoons.The shape features of the pupa are considered for the classification process and were obtained without cutting the cocoon.A novel point interpolation method is used for the computation of the width and height of the cocoon.Different dimensionality reduction methods are employed to enhance the performance of the model.The preprocessed features are fed to the powerful ensemble learning method AdaBoost and used logistic regression as the base learner.This model attained a mean accuracy of 96.3%for FC1 and FC2 in cross-validation and 95.3%in FC1 and 95.1%in FC2 for external validation.

关键词： Sericulture Gender classification Stratified k-fold cross-validation Machine learning AdaBoost

What would a US green hydrogen energy economy look like?

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Clean Energy 2023年第5期7卷 1148-1172页

作者： thomas Tonon Independent researcher Ph.D.Aerospace and Mechanical SciencesPrinceton University1971.11 Bolfmar AvenuePrinceton JunctionNJ 08550USA

Detailed description is given for a hypothetical US hydrogen economy with solar and wind energy supplying virtually all current energy needs and with electrolytic hydrogen the energy carrier and storage medium.Fossil fuels provide nonfuel products(plastics,chemicals,cement and asphalt).Only current technologies are considered and hydrogen storage accommodates generation intermit-tency and variability,using pit storage of high-pressure vessels in open air,yielding daily storage round-trip energy installation costs of 722 and 538$/kWh for electric and thermal,respectively;and for power,2351 and 2240$/kW for electric and thermal,respectively.For long-duration storage,the costs are 94.1 and 23.8$/kWh and 937 and 845$/kW,respectively.Increased energy generation 20%over baseline accommodates low-season generation,obviates much required storage and ensures that reserves are topped off;96%of US 2022 total energy consumption is provided for.In the default scenario(demand energy portions:half photovoltaic,quarter on-shore wind and quarter offshore wind),the surface area for the farms(including offshore surface)requires~4.6%of the US 48-state land area.About 350 pit storage sites provide both daily and long-duration storage,with the latter accounting for complete loss of generation for 4 days over a quarter of the nation.Hydrogen pipelines and a renewed electric grid transmit and distribute energy.The installation cost of the public infrastructure is~$27.8 trillion for the default scenario.Alternative scenarios show significant in-frastructure and cost savings when batteries are used for transportation and/or utility storage,provided current insufficiencies can be overcome.Broadly,cost levels in money,surface and infrastructure are within existing levels already achieved in historical events and modern living.

关键词： hydrogen economy renewable energy hydrogen storage hydrogen pipelines sustainable net zero

Differential transport of a guild of mutualistic root aphids by the ant Lasius flavus

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Current Zoology 2023年第4期69卷 409-417页

作者： thomas Parmentier Research Unit of Environmental and Evolutionary Biology Namur Institute of Complex Systemsand Institute of LifeEarthand the EnvironmentUniversity of NamurRue de Bruxelles 61B-5000 NamurBelgium Terrestrial Ecology Unit(TEREC) Department of BiologyGhent UniversityK.L.Ledeganckstraat 35B-9000 GentBelgium

Mutually beneficial associations are widespread in ecological networks.They are typically assembled as multispecies guilds of symbionts that compete for one or more host species.The ant Lasius flavus engages in an intriguing and obligate mutualistic association with a community of aphids that are cultivated on plant roots in its nests.The ant displays a repertoire of amicable behaviors toward the aphids,including their transport.I examined whether L.flavus preferentially carried some of the root aphids.Using a no-choice and a choice experiment,I comparatively analyzed the transport rate of 5 obligate and one loosely associated species back to the ant nest and used the transport rate of the ant larvae as a reference.All associated root aphids were carried back to the nest,but in a clear preferential hierarchy.Geoica utricularia,Forda Formicaria,and Trama rara were rapidly transported,but slower than the own larvae.Tetraneura ulmi and Geoica setulosa were collected at a moderate rate and the loosely associated Aploneura lentisci was slowly retrieved.In contrast,different species of unassociated aphids were not transported and even provoked aggressive behavior in L.flavus.This study revealed that co-occurring symbionts may induce different degrees of host attraction,which ultimately may affect the coexistence and assembly of ant-symbiont communities.

关键词： competition Formicidae honeydew rescue behavior symbiosis trophobiont

Occurrence of an endangered grassland butterfly is mainly driven by habitat heterogeneity,food availability,and microclimate

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Insect Science 2022年第4期29卷 1211-1225页

作者： Gwydion Scherer thomas Fartmann Department of Biodiversity and Landscape Ecology University of OsnabrückOsnabrückGermany Institute of Biodiversity and Landscape Ecology(IBL) MünsterGermany

The Marsh Fritillary(Euphydryas aurinia)was once widespread in large parts of Central Europe.However,in the course of the last century,populations of the butterfly largely collapsed.Here,we surveyed patch and microhabitat occupancy and its drivers in one of the last vital populations in calcareous grasslands.Our study revealed that environmental conditions at the landscape and habitat level determined the occurrence of E.aurinia in a montane agricultural landscape with low land-use intensity.Patch occupancy increased with the cover of Devil's-bit Scabious(Succisa pratensis)grasslands in the surroundings of the patches,habitat heterogeneity and host-plant cover.Microhabitat occupancy was driven by a warm microclimate and high availability of host plants.In the well-connected landscape of nutrient-poor grasslands,patch occupancy of E.aurinia was driven by parameters defining a high habitat quality.Habitat heterogeneity very likely buffers E.aurinia populations against environmental stochasticity and,hence,enhances long-term viability.For the gregariously feeding caterpillars of E.aurinia,host-plant biomass is essential.Due to their more luxuriant growth,S.pratensis plants were clearly preferred,although the Glossy Scabious(Scabiosa lucida)was also widespread.Additionally,the growth of large Succisa plants was favored by soil humidity and grassland abandonment.To cope with the adverse macro-and mesoclimatic conditions of the study area,females of the butterfly selected host plants growing in extraordinarily warm microhabitats for oviposition.To secure long-term viability of E.aurinia populations,we recommend creating mosaics of traditionally managed grasslands and early stages of abandonment within the patches.

关键词： agricultural landscape calcarcous grassland hay meadow host-plant abundance land-use change traditional management

Daily activity rhythms, chronotypes, and risk-taking behavior in the signal crayfish

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Current Zoology 2022年第2期68卷 177-183页

作者： Valerio SBRAGAGLIA thomas BREITHAUPT Department of Marine Renewable Resources Marine Science Institute(ICM-CSIC)Passeig Maritim de la Barceloneta3708003 BarcelonaSpain Department of Biology and Ecology of Fishes Leibniz-lnstitute of Freshwater Ecology and Inland FisheriesMüggelseedamm 31012587 BerlinGermany Department of Biological and Marine Sciences University of HullCottingham RoadHull HU67RXUK

Consistent inter-individual differences in daily activity rhythms(i.e.,chronotypes)can have ecological consequences in determining access to food resources and avoidance of predators.The most common measure to characterize chronotypes in animals as well as humans is the onset of activity(i.e.,early or late chronotypes).However,daily activity rhythms may also differ in the relative amount of activity displayed at particular time periods.Moreover,chronotypes may also be linked to other consistent inter-individual differences in behavior(i.e.,personality),such as the propensity to take risks.Here,we used the signal crayfish Pacifastacus leniusculusto test the presence of chronotypes and risk-taking personality traits and a potential behavioral syndrome between these traits.We first exposed crayfish to 5 days of light-darkness to measure daily activity rhythms and then we applied a visual predator-simulating stimulus in 2 different contexts(neutral and food).Our results showed consistent(i.e.,across 5 days)inter-individual differences in the relative nocturnal activity displayed in the early and middle,but not in the late part of darkness hours.Moreover,while crayfish displayed inter-individual differences in risk-taking behavior,these were not found to be consistent across 2 contexts.Therefore,we were not able to formally test a behavioral syndrome between these 2 traits.In conclusion,our study provides the first evidence of chronotypes in the relative amount of activity displayed at particular time periods.This could be a valuable information for applied ecological aspects related to the signal crayfish,which is a major invasive species of freshwater ecosystems.

关键词： behavioral syndrome biological rhythms boldness feeding locomotor activity

CLASSIFICATIONS OF DUPIN HYPERSURFACES IN LIE SPHERE GEOMETRY

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Acta Mathematica Scientia 2024年第1期44卷 1-36页

作者： thomas E.CECIL Department of Mathematics and Computer Science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in S^(n)(or R^(n))that have been obtained in the context of Lie sphere geometry.The emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in spheres.Along with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of S^(n)(or R^(n)),are described in detail.The paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures

Nanoscale chemical segregation to twin interfaces in τ-MnAl-C and resulting effects on the magnetic properties

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Journal of Materials Science & Technology 2023年第3期134卷 22-32页

作者： Panpan Zhao Markus Gusenbauer Harald Oezelt Daniel Wolf thomas Gemming thomas Schrefl Kornelius Nielsch thomas George Woodcock Leibniz IFW Dresden Helmholtzstr.20Dresden 01069Germany TU Dresden Institute of Materials ScienceDresden 01062Germany Department for Integrated Sensor Systems Danube University KremsKrems an der Donau 3500Austria

In this study,aberration-corrected scanning transmission electron microscopy coupled with electron energy-loss spectroscopy(STEM-EELS)was used to investigate the atomistic structure and chemical com-position of true twin and order twin boundaries in ferromagneticτ-MnAl-C.True twins and order twins were distinguished based on the diffraction patterns using TEM.No elemental segregation was observed at the coherent true twin boundary but some Mn enrichment within a region of about 1.5-2 nm was found at the incoherent true twin boundary.A transition region with Mn enrichment about 4-6 nm wide was found at the order twin boundary.A carbon cluster with a size of around 5 nm was also found at the twin boundary.Micromagnetic simulations were conducted to study the effect of this chemical seg-regation at twin interfaces on the magnetic properties.The results showed that the coercivity tends to increase with increasing structural and chemical disorder at the interface.

关键词： τ-MnAl-C Twin boundaries Elemental segregation STEM-EELS Micromagnetic simulations

Development of German-Ukrainian cooperations for education and research in photogrammetry and laser scanning

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Geo-Spatial Information Science 2021年第1期24卷 152-159,I0016页

作者： thomas Luhmann Institute for Applied Sciences and Geoinformatics Jade University of Applied Sciences OldenburgOldenburgGermany

Since 2011 an intensive international cooperation has been in place between the Institute for Applied Photogrammetry and Geoinformatics(IAPG)at the Jade University of Applied Sciences in Oldenburg,Germany,and various Ukrainian universities.Following an initial contact by Prof.Gottfried Konecny,the first visit was organized,and was followed by many more.In subsequent years an intensive cooperation was established particularly with the National University for Construction and Architecture(KNUCA)in Kiev.In addition to architects and civil engineers,KNUCA also trains geodesists,geo-information scientists and landscape planners.The cooperation today includes the reciprocal exchange of scientists and students,research projects,courses and cooperation at many other levels.In addition,a commercial company has been established,SPM3D LLC,which now employs more than 14 engineers in the field of 3D acquisition,point cloud processing and modeling.This article summarizes the history of the cooperation and presents the results of associated student projects.In addition,results of joint work on the development of a virtual laser scanner are presented,part of a German-Ukrainian initiative to digitize teaching.

关键词： Internationalization technology transfer curricula reform photogrammetry laser scanning e-learning

Strategically designing layered two-dimensional SnS_(2)-based hybrid electrodes: A futuristic option for low-cost supercapacitors

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Journal of Energy Chemistry 2023年第10期85卷 394-417,I0011页

作者： Susmi Anna thomas Jayesh Cherusseri Centre for Advanced Functional Materials(CAFM) Department of PhysicsBishop Moore CollegeMavelikaraKerala 690110India Sunway Centre for Electrochemical Energy and Sustainable Technology(SCEEST) School of Engineering and TechnologySunway UniversityNo.5 Jalan UniversityBandar SunwayPetaling Jaya 47500Malaysia

Supercapacitors are promising energy storage devices in current century due to their high specific capacitance, cyclic stability, high power density, and high voltage rating. Due to their excellent electrochemical properties, supercapacitors are invariably used in a multitude of applications ranging from portable electronics to electric vehicles. The electrochemical performance of a supercapacitor mainly depends on the type of electrode-active material used in it. Thereby a careful selection is mandatory to achieve the excellency. Nanostructured electrode-active materials such as carbon nanomaterials, transition metal oxides,transition metal dichalcogenides(TMDs), electronically conducting polymers, etc. are invariably used for supercapacitor application. Among these, TMDs have received great interest, particularly transition metal disulfides such as molybdenum disulfide, tin disulfide(SnS_(2)), etc. Tin is abundant on the earth with excellent charge storage capabilities, attracted great scientific interest for application as electrode materials in supercapacitors. Good electronic conductivity, long cycling life and low-cost are its added advantages.Herein, we discuss the recent trends in layered two-dimensional(2D) SnS_(2)-based electrodes to develop low-cost supercapacitors. Initially, their crystal structure, basic properties, synthesis methods are discussed. Further, strategically designing electrode nanostructures to achieve excellent electrochemical performance is reviewed then after. This includes material design in terms of morphology, pore-size,and shape as well as preparation of 2D SnS_(2)-based nanocomposite electrodes. Furthermore, the challenges and future perspectives of 2D SnS_(2)-based supercapacitors are included.

关键词： SnS_(2) Supercapacitor Transition metal dichalcogenides Electrochemical energy storage