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Opto-Electronic Advances 2022年第6期5卷 44-54页

作者： Sarah Dittrich Maximilian Spellauge stephan Barcikowski Heinz P.Huber Bilal Gökce Technical Chemistry I and Center of Nanointegration Duisburg-Essen(CENIDE) University of Duisburg-EssenUniversitaetsstr.745141 EssenGermany Department of Applied Sciences and Mechatronics Munich University of Applied SciencesLothstr.3480335 MunichGermany Materials Science and Additive Manufacturing School of Mechanical Engineering and Safety EngineeringUniversity of WuppertalGaußstraße 2042119 WuppertalGermany.

Laser ablation in liquid is a scalable nanoparticle production method with applications in areas like catalysis and *** to laser-liquid interactions,different energy dissipation channels such as absorption by the liquid and scattering at the ablation plume and cavitation bubble lead to reduced laser energy available for nanoparticle *** pulse durations cause unwanted nonlinear effects in the liquid,and for ns pulses,intra-pulse energy deposition attenuation effects are to be ***,intermediate pulse durations ranging from hundreds of picoseconds up to one nanosecond have rarely been studied in particular in single-pulse *** this study,we explore the pico-to nanosecond pulse duration regimes to find the pulse duration with the highest ablation *** find that pulse durations around 1-2 ns enable the most efficient laser ablation in liquid since the laser beam shielding by the ablation plume and cavitation bubble sets in only at longer pulse ***,pump-probe microscopy imaging reveals that the plume dynamics in liquids start to differ from plume dynamics in air at about 2 ns after pulse impact.

关键词： colloid synthesis nanoparticles cavitation bubble power-specific productivity ablation plume vapor formation

Power flow forecasts at transmission grid nodes using Graph Neural Networks

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Energy and AI 2023年第4期14卷 189-200页

作者： Dominik Beinert Clara Holzhuter Josephine M.Thomas stephan Vogt Fraunhofer Institute for Energy Economics and Energy System Technology IEE Joseph-Beuys-Straße 8Kassel34117Germany Intelligent Embedded Systems Lab University of KasselWilhelmshöher Allee 73Kassel34121Germany

The increasing share of renewable energy in the electricity grid and progressing changes in power consumption have led to fluctuating,and weather-dependent power *** ensure grid stability,grid operators rely on power forecasts which are crucial for grid calculations and *** this paper,a Multi-Task Learning approach is combined with a Graph Neural Network(GNN)to predict vertical power flows at transformers connecting high and extra-high voltage *** proposed method accounts for local differences in power flow characteristics by using an Embedding Multi-Task Learning *** use of a Bayesian embedding to capture the latent node characteristics allows to share the weights across all transformers in the subsequent node-invariant GNN while still allowing the individual behavioral patterns of the transformers to be *** the same time,dependencies between transformers are considered by the GNN architecture which can learn relationships between different transformers and thus take into account that power flows in an electricity network are not independent from each *** effectiveness of the proposed method is demonstrated through evaluation on two real-world data sets provided by two of four German Transmission System Operators,comprising large portions of the operated German transmission *** results show that the proposed Multi-Task Graph Neural Network is a suitable representation learner for electricity networks with a clear advantage provided by the preceding embedding *** is able to capture interconnections between correlated transformers and indeed improves the performance in power flow prediction compared to standard Neural Networks.A sign test shows that the proposed model reduces the test RMSE on both data sets compared to the benchmark models significantly.

关键词： Power flow forecasting Graph Neural Network Graph Convolutional Network Embedding Multi-Task Learning

Advanced surface coil layout with intrinsic noise cancellation properties for surface-NMR applications

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Magnetic Resonance Letters 2023年第2期3卷 140-149,I0004页

作者： Thomas Hiller stephan Costabel Raphael Dlugosch Tobias Splith Mike Müller-Petke Federal Institute for Geosciences and Natural Resources Wilhelmstr.25-30Berlin13595Germany Federal Institute for Geosciences and Natural Resources Stilleweg 2Hannover3655Germany Leibniz Institute for Applied Geophysics Stilleweg 2Hannover30655Germany

A recent study demonstrated that in small-scale prepolarized surface nuclear magnetic resonance(SNMR-PP)measurements with a footprint of a few square meters,customized PP switch-off ramps can serve as an efficient excitation mechanism,eliminating the requirement for a conventional oscillating excitation *** approach enables the detection of short relaxation signals from the unsaturated soil zone and can,therefore,be used to directly provide soil moisture and pore geometry *** ultimately such small-scale SNMR-PP setups are intended for a mobile application,it is necessary to develop strategies that allow for speedy measurement progress and do not require noise cancellation protocols based on reference ***,we developed a new concentric figure-of-eight(cFOE)loop layout that combines the direction independence of a circular loop with the intrinsic noise cancellation properties of a classical *** approach significantly decreases the measurement time because suitable signal-to-noise ratios are reached much faster compared to a classical circular loop and will bring us one step further toward fast and non-invasive soil moisture mapping applications.

关键词： Surface-NMR Prepolarization Noise cancellation Loop layout

Self-consistent Maxwell–Bloch model for highorder harmonic generation in nanostructured semiconductors

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Photonics Research 2022年第9期10卷 2099-2106页

作者： ANTON RUDENKO MARIA K.HAGEN JÖRG HADER stephan W.KOCH JEROME V.MOLONEY Arizona Center for Mathematical Sciences and Wyant College of Optical Sciences University of ArizonaTucsonArizona 85721USA Department of Physics and Material Sciences Center Philipps-Universität MarburgMarburg 35032Germany

In pursuit of efficient high-order harmonic conversion in semiconductor devices,modeling insights into the complex interplay among ultrafast microscopic electron–hole dynamics,nonlinear pulse propagation,and field confinement in nanostructured materials are urgently ***,a self-consistent approach coupling semiconductor Bloch and Maxwell equations is applied to compute transmission and reflection high-order harmonic spectra for finite slab and sub-wavelength nanoparticle *** increase in the generated high harmonics by several orders of magnitude is predicted for gallium arsenide nanoparticles with a size maximizing the magnetic dipole *** as a conceptual and predictive tool for ultrafast spatiotemporal nonlinear optical responses of nanostructures with arbitrary geometry,our approach is anticipated to deliver new strategies for optimal harmonic manipulation in semiconductor metadevices.

关键词： harmonic Bloch Maxwell

Characterizing bubble interaction effects in synchronous-double-pulse laser ablation for enhanced nanoparticle synthesis

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Photonics Research 2023年第12期11卷 2054-2071页

作者： FARBOD RIAHI ALEXANDER BUßMANN CARLOS DONATE-BUENDIA STEFAN ADAMI NICOLAUS AADAMS stephan BARCIKOWSKI BILAL GOKCE Chair of Materials Science and Additive Manufacturing School of Mechanical Engineering and Safety EngineeringUniversity of Wuppertal42119 WuppertalGermany Chair of Aerodynamics and Fluid Mechanics School of Engineering and DesignTechnical University of Munich85748 Garching bei MünchenGermany Munich Institute of Integrated Materials Energyand Process Engineering(MEP)Technical University of Munich85748 Garching bei MünchenGermany Technical Chemistry I and Center for Nanointegration Duisburg-Essen(CENIDE) University of Duisburg-Essen45141 EssenGermany

To further advance nanomaterial applications and reduce waste production during synthesis,greener and sustainable production methods are *** laser ablation in liquid(PLAL)is a green technique that enables the synthesis of *** study uses synchronous-double-pulse PLAL to understand bubble interaction effects on the nanoparticle *** adjusting the lateral separation of the pulses relative to the maximum bubble size,an inter-pulse separation is identified where the nanoparticle size is *** cavitation bubble pair interaction is recorded using a unique coaxial diffuse shadowgraphy *** system allows us to record the bubble pair interaction from the top and side,enabling the identification of the bubble’s morphology,lifetime,volumetric,and displacement *** is found that the collision and collapse of the bubbles generated at a certain inter-pulse separation results in a larger nanoparticle *** results mark a significant advancement by controlling the abundance of larger nanoparticles in PLAL,where previous efforts were primarily focused on reducing the average nanoparticle *** experimentally observed trends are confirmed by numerical simulations with high spatial and temporal *** study serves as a starting point to bridge the gap between upscaled multi-bubble practices and fundamental knowledge concerning the determinants that define the final nanoparticle size.

关键词： interaction synthesis bubble

Impacts of increasing maize stalk retention amount on soil respiration and temperature sensitivity

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International Journal of Agricultural and Biological Engineering 2022年第2期15卷 135-141页

作者： Hongfang Yuan Gang Wang Dongyan Huang stephan Glatzel Jian Zhuang Honglei Jia College of Biological and Agricultural Engineering Jilin UniversityChangchun 130022China Department of Geography and Regional Research University of ViennaVienna 1090Austria Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchun 130022China

Conservation tillage with maize stalk retention is an effective method to replenish soil *** availability plays a major role in the control of soil respiration(SR).However,it is not known how different degrees of maize stalk retention control SR and its temperature sensitivity(Q_(10)).To investigate the effect of maize stalk retention amount on SR and Q_(10),four maize(Zea mays L.)stalk retention treatments,including(i)control treatment(CT)without maize stalk retention,(ii)standing maize stalk retention(SCR),(iii)partial maize stalk retention with‘three-year cycle’(TYR)and(iv)chopped maize stalk retention(CCR)was set *** order to investigate the differences in soil nutrient,soil organic carbon(SOC)quality and soil microbial biomass among four treatments,soil analysis with 6 replicates was *** experimental results showed that SR rates were 1.07,0.88,0.59 and 0.37 g/kg of dry soil,and the average Q_(10)was 1.535,1.585,1.62 and 1.725 for CT,SCR,TYR and CCR,*** maize stalk retention led to the reduction of soil microbial abundance and labile carbon *** correlation analysis showed that soil microbial abundance had a positive correlation with SR,while labile carbon fraction had a negative correlation with Q_(10).In short,increasing the amount of maize stalk retention decreases SR while increasing Q_(10)in northeast *** research could provide a reference value for balancing carbon sequestration and carbon decomposition in farming practice.

关键词： stalk management soil nutrient carbon composition microbial biomass laboratory incubation

Declaring income versus declaring taxes in tax compliance experiments:Does the design of laboratory experiments affect the results?

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Economic and Political Studies 2023年第3期11卷 334-349页

作者： stephan Muehlbacher Andre Hartmann Erich Kirchler James Alm Department of Psychology and Psychodynamics Karl Landsteiner University of Health SciencesKremsAustria Department of Occupational Economic and Social PsychologyUniversity of ViennaViennaAustria Institute for Advanced Studies ViennaAustria Department of Economics Tulane UniversityNew OrleansLAUSA

Laboratory experiments are frequently criticised,in part because of the sensitivity of the results to specific features of the *** paper addresses an important question regarding the key aspect of the experimental environment:How should the dependent variable–participants’choices–be operationalised?For the specific context of laboratory research on income tax compliance,we compare the effects of the two most common operationalisation types:the declaration of gross income versus the declaration of tax *** is found that compliance is higher when participants indicate their tax payment than when they declare their *** is also discovered that the effects of the three policy parameters of the economic model(the tax rate,audit probability and fine rate)are stronger when participants declare their taxes than when they declare their *** results are relevant for interpreting prior and future experimental evidence on tax compliance and can explain some contradictory previous *** broadly,this study suggests that the results of laboratory experiments may depend on specific features of the experimental design,which proposes a strong need for more systematic methodological research.

关键词： Laboratory experiments experimental design tax compliance tax rate audit probability fine rate

(Not) an elementary question:How to mobilize the iron in the wall?

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Molecular Plant 2021年第10期14卷 1610-1611页

作者： stephan Clemens Department of Plant Physiology and Faculty of Life Sciences:Food Nutrition and HealthUniversity of BayreuthUniversitätsstrasse 3095440 BayreuthGermany

Photosynthesis,respiration,and countless other processes are dependent on proteins that carry iron(Fe)as an essential *** Fe was recruited for biological functions early in evolution,it was an available *** Earth's at... 详细信息

关键词： element. elementary sulfide

On combinatorial Gauss-Bonnet Theorem for general Euclidean simplicial complexes

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Frontiers of Mathematics in China 2016年第5期11卷 1345-1362页

作者： stephan KLAUS Scientific Administrator of the MFO and Adjunct Professor at Mainz University Mathematisches Forschungsinstitut Oberwolfach gGmbH (MFO) Schwarzwaldstrasse 9-11 D-77709 Oberwolfach-Walke Germany

For a finitely triangulated closed surface M2, let αx be the sum of angles at a vertex x. By the well-known combinatorial version of the 2- dimensional Gauss-Bonnet Theorem, it holds ∑x（2π- αx） =2αχ（M^2）, where X denotes the Euler characteristic of M^2, αx denotes the sum of angles at the vertex x, and the sum is over all vertices of the triangulation. We give here an elementary proof of a straightforward higher-dimensional generalization to Euclidean simplicial complexes K without assuming any combinatorial manifold condition. First, we recall some facts on simplicial complexes, the Euler characteristics and its local version at a vertex. Then we define δ（τ） as the normed dihedral angle defect around a simplex τ. Our main result is ∑τ（-1）^dim（τ）δ（τ） = χ（K）, where the sum is over all simplices τ of the triangulation. Then we give a definition of curvature k（x） at a vertex and we prove the vertex-version ∑x∈K0 k（x） = χ（K） of this result. It also possible to prove Morse-type inequalities. Moreover, we can apply this result to combinatorial （n ＋ 1）-manifolds W with boundary B, where we prove that the difference of Euler characteristics is given by the sum of curvatures over the interior of W plus a contribution from the normal curvature along the boundary B： χ（W）- 1/2 χ（B） = ∑τ∈W-B（-1）^dim（τ）δ（τ）＋ ∑τB（-1）^dim（τ）ρ（τ）.

关键词： Curvature dihedral angle Euclidean simplex triangulation Euler characteristic Euler manifold combinatorial manifold pseudo manifold

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刑法中容许的案情认识错误之司法审查

法治现代化研究 2024年第3期8卷 190-200页

作者： [德]斯特凡·克里斯托夫孙晓倩(译) 蔡桂生(译) 德国雷根斯堡大学法律系中国人民大学法学院中国人民大学刑事法律科学研究中心暨法学院德国波恩大学

以假想防卫、假想避险等情形为其内容的容许的案情认识错误,是刑法总则犯罪论中的“经典问题”。为良好地解答这道有挑战性的难题,应当明了与该论题有关的各种意见的相应理论背景,以及其所对应的各种犯罪论构造。容许的案情认识错误与... 详细信息

以假想防卫、假想避险等情形为其内容的容许的案情认识错误,是刑法总则犯罪论中的“经典问题”。为良好地解答这道有挑战性的难题,应当明了与该论题有关的各种意见的相应理论背景,以及其所对应的各种犯罪论构造。容许的案情认识错误与容许错误不同,前者是对本体性的具体案情发生了认识错误,而后者是对规范性的刑法条文本身产生了理解偏差。尽管在容许的案情认识错误问题上产生了严格罪责论、消极的构成要件要素论、排除故意不法的限制罪责论和法律效果援用之限制罪责论四种不同意见,但是,以足够的信心分别权衡这各种意见的相应论据,可以在这四种方案中做出理性的选择,从而很好地回答容许的案情认识错误的问题。

关键词：假想防卫容许的案情认识错误犯罪构造意见分歧