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Cyclicity of the Lower Buntsandstein in the eastern part of the Central European Basin:implications for Early Triassic palaeogeography and for geochronological calibration

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Journal of Palaeogeography 2024年第2期13卷 252-292页

作者： Anna becker Polish Geological Institute-National Research Institute 4 Rakowiecka str.00-975 WarsawPoland

Lower Buntsandstein small—scale cycles recognized in the Central European Basin(CEB) are readily used for astrochronological calibration of the Early Triassic time scales,although they are not well studied *** borehole sections from the eastern part of the CEB,forming a south-north transect perpendicular to the basin axis,were studied in terms to better understand the depositional history of the Lower Buntsandstein developed as the Baltic Formation in the studied Polish part of the *** sedimentary facies were recognized,based on lithological and sedimentological investigations of 655.7 m of drill cores from the Otyń IG 1,Gorzów Wielkopolski IG 1 and Kamień Pomorski IG 1 *** facies can be grouped according to a lithological criterion into facies of predominantly siliciclastic lithology(including 9facies types) and facies of predominantly carbonate lithology(including 2 facies types).Facies analysis allowed to distinguish 8 facies associations of:1) alluvial fan,2) playa,3) sandy-muddy coastal plain,4)embayment and distal delta,5) lagoon,6) sand bars or shoals,7) ooidal shoals or bars,and 8) ***-upward(DC) and shallowing-upward(SC) sedimentary cycles were recognized in parts of the Baltic Formation,with DCs dominating in the southernmost located Otyń IG 1,and SCs dominating in Gorz ow Wielkopolski IG 1,located in the axial part of the *** cycles are very *** statistical significance of the sedimentary cycles is relatively low according to Markov-chain analysis conducted with the phpSedistat software of Stanova et al.(2009).Analysis of small—scale cycles performed on well logs of investigated boreholes and additional boreholes in the vicinity of Otyń IG 1,implementing the earlier study of becker(2005),showed that the correlation of well-log cycles(GR cycles) and sedimentary cycles is not *** cycles can be roughly correlated with lithological carbonate—siliciclastic cycles(c-s cycles),refle

关键词： Triassic Lower Buntsandstein Cyclicity Central European Basin

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Temperature Difference and Stack Plate Spacing Effects on Thermodynamic Performances of Standing-Wave Thermoacoustic Engines Driven by Cryogenic Liquids and Waste Heat

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Journal of Thermal Science 2022年第5期31卷 1434-1451页

作者： GUO Lixian ZHAO Dan becker Sid Department of Mechanical Engineering College of EngineeringUniversity of CanterburyPrivate Bag 4800Christchurch8041New Zealand

The standing-wave thermoacoustic engines(TAE)are applied in practice to convert thermal power into acoustic one to generate electricity or to drive cooling *** there is a number of existing numerical researches that provides a design tool for predicting standing-wave TAE performances,few existing works that compare TAE driven by cryogenic liquids and waste heat,and optimize its performance by varying the stack plate *** present work is primarily concerned with the numerical investigation of the performance of TAEs driven by cryogenic liquids and waste *** this,three-dimensional(3-D)standing-wave TAE models are ***-and time-independence studies are conducted *** validations are then performed by comparing with the numerical results available in the *** validated model is then applied to simulate the standing-wave TAEs driven by the cryogenic liquids and the waste heat,as the temperature gradientΔT is *** is found that limit cycle oscillations in both systems are successfully generated and the oscillations amplitude is increased with increasedΔ*** is identified with acoustic streaming and the flow reversal occurring through the *** studied are then conducted between the cryogenic liquid-driven TAE and that driven by waste heat in the presence of the same temperature gradientΔ*** is shown that the limit cycle frequency of the cryogenic liquid system is 4.72%smaller and the critical temperatureΔT_(cri)=131 K is lower than that of the waste heat system(ΔT_(cri)=187 K).Furthermore,the acoustic power is increased by 31%and the energy conversion efficiency is found to increase by 0.42%.Finally,optimization studies on the stack plate spacing are conducted in TAE system driven by cryogenic *** is found that the limit cycle oscillation frequency is increased with the decreased ratio between the stack plate spacing and the heat penetration *** the ratio is set to between 2 and

关键词： thermoacoustic engine standing-wave cryogenic thermodynamics acoustical energy plate spacing heat transfer acoustic streaming

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Ultrasonically Assisted Cutting of Histological Sections for Reducing the Environmental and Financial Impact of Microtomy

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Chinese Journal of Mechanical Engineering 2022年第3期35卷 200-206页

作者： Dong Wang Daniel De becker Anish Roy Wolfson School of Mechanical and Manufacturing Engineering Loughborough UniversityLoughborough LE113TUUK Department of Engineering College of EngineeringMathematics and Physical SciencesUniversity of ExeterExeter EX44QFUK

Modern-day microtomy requires high precision equipment to thinly section biological *** sectioned tissue must be of good quality not showing cutting tracks or so-called *** quality of these sections is dependent on the blade wear,which is related to the hardness of the tissue sample,cutting angle and cutting speed.A test rig has been designed and manufactured to allow these parameters to be *** has allowed for the blade wear to be analysed and quantified,and this has been completed for both ultrasonically assisted and conventional *** obtained results showed a 25.2%decrease in average blade roughness after 38 cuts when using the ultrasonically assisted cutting *** data also showed no adverse effect on the quality of the slides produced when using this cutting ***,the cutting force measured for both cutting regimes showed that ultrasonically assisted cutting required less force compared to conventional *** the reduction of surface roughness and force,it is possible to state that ultrasonically assisted cutting reduces the wear of the blade,thereby increasing the life of the *** increase of just 10%in blade life would yield a cost saving of approximately 25%thereby reducing the environmental and financial impact of microtomy.

关键词： Microtome Ultrasonically assisted cutting Blade wear

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Model Experiments on Melting of Alloys with Low Melting Temperature in a Medium with High Melting Temperature

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Journal of Iron and Steel Research International 1999年第2期6卷 1-9页

作者： becker Jens-Ulrik Oeters Franz Thyssen-Krupp Stahl GmbH Technical University Berlin

Experiments of alloy melting were carried out in water/HCl H 2O eutectic model system. The eutectic has a solid liquid equilibrium temperature of -74 ℃. 5 cm diameter spheres of the eutectic in which three thermocouples in the core, on the edge and in the middle between them had been positioned were cooled to -196 ℃ in liquid nitrogen. After cooling the spheres were immersed into water of 10 ℃, and the changes of temperatures with time in the three thermocouples were measured. In some experiments the temperature on the outer side of the spheres where an ice shell grew up was also measured. In these experiments, the growing rate of the shell was additionally determined. The results for the first minute of the melting process, where the system can be considered as one dimensional, were described by an exact solution of Fouriers equation. The density of liquid ferromanganese at 1 500 ℃ was measured.

关键词： alloy melting model experiment

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Joint Loading Estimation Method for Horse Forelimb High Jerk Locomotion:Jumping

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Journal of Bionic Engineering 2019年第4期16卷 674-685页

作者： Joanne becker Mermoz Emmanuel Linares Jean-Marc Airbus Helicopters Aeroport de Marseille ProvenceMarignane 13700France Aix Marseille Univ CNRSISMInst Movement SciMarseille 13009France

Maximal local loads in animal joints are necessary to design bio-inspired mechanical *** studies presented methods to determine joint reaction forces in humans and ***,many of these methods are invasive,and no work has been published yet about the joint reaction forces in the horse forelimb during ***-invasive methods to measure the kinematics and ground reaction force of a horse forelimb were used in this work.A musculoskeletal model of horse forelimb was built with mechanical methods for the estimation of joint reaction *** entire forelimb was reconstructed by scanning real bones geometry with a 3D optical scanner and modeling all the muscles on a Computer Assisted Design(CAD)*** model dynamics were simulated with OpenSim in order to estimate the joint *** study allows knowing an order of magnitude of the loads at the joints at jumping in order to determine latter the maximal joint contact loading values that will be a key at designing bio-inspired joints for mechanical assemblies.

关键词： joint loading jumping kinematics modelling OpenSim

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Data-driven prediction of plate velocities and plate deformation of explosive reactive armor

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Defence Technology（防务技术） 2022年第12期18卷 2141-2149页

作者： Marvin becker Andreas Klavzar Thomas Wolf Melissa Renck Institute of Saint-Louis 5 Rue du Général Cassagnou68330Saint LouisCedexFrance Ecole Centrale de Lille CitéScientifique59651Villeneuve d'AscqCedexFrance

Explosive reactive armor(ERA)is currently being actively developed as a protective system for mobile devices against ballistic threats such as kinetic energy penetrators and shaped-charge *** mobility,the aim is to design a protection system with a minimal amount of required *** efficiency of an ERA is sensitive to the impact position and the timing of the ***,different designs have to be tested for several impact scenarios to identify the best *** analytical models are not predicting the behavior of the ERA accurately enough and experiments,as well as numerical simulations,are too time-consuming,a data-driven model to estimate the displacements and deformation of plates of an ERA system is proposed *** ground truth for the artificial neural network(ANN)is numerical simulation results that are validated with *** ANN approximates the plate positions for different materials,plate sizes,and detonation point positions with sufficient accuracy in *** a future investigation,the results from the model can be used to estimate the interaction of the ERA with a given ***,a measure for the effectiveness of an ERA can be ***,an optimal ERA can be designed and analyzed for any possible impact scenario in negligible time.

关键词： Artificial neural network Explosive reactive armor Finite element simulation Particle simulation Flash X-ray

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Laboratory rearing of solitary bees and wasps

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Insect Science 2016年第6期23卷 918-923页

作者： Mira C. becker Alexander Keller Department of Animal Ecology and Tropical Biology Biocenter University of Wurzburg Wurzburg Germany

Ecological experiments often require standardized methods that exclude natural variation and allow manipulation of a single parameter. It has been shown that domesticated honey bee larvae are raisable in a controlled environment. Here we demonstrate that this approach is also transferable to wild solitary bees and wasps without inducing negative effects on their development. Wells may also be supplemented with the antibiotic substance oxytetracycline to control the presence of bacteria. The method thus provides a useful tool to investigate offspring recruitment and larval development in solitary bees and wasps, plus their responses to manipulation of factors as for example diets, toxins and microbiota.

关键词： diet manipulation ecotoxicology larval ontogeny Osmia bicornis oxytetracycline pathogens

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Why People Live in Flood-Prone Areas in Akuressa, Sri Lanka

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International Journal of Disaster Risk Science 2018年第2期9卷 143-156页

作者： Johan Askman Olof Nilsson Per becker Division of Risk Management and Societal Safety Lund University

To investigate why people live in areas at high risk of floods, a qualitative case study was carried out in the areas around Akuressa, in southwest Sri Lanka. Data collection consisted mainly of semistructured interviews with local residents and government officials. The purpose was to study why people live in areas at high risk of floods, by looking beyond the purely physical aspects of living with hazards and exploring the underlying social factors. Four main factors were identified: an overall good living situation; a sense of place; difficulties relocating; and being well-adapted to the situation. The analysis also examined whether government officials shared the views of local residents. The findings highlighted both areas of consensus and discrepancies related to risk awareness, and the efficiency of risk reduction measures that had been implemented by the government. The case study identified and explored underlying social factors, such as risk normalization, risk trade-offs, and push-and-pull processes, which seem to influence the decision to live in a high-risk area.

关键词： Flood risk Risk awareness Risk perception Sri Lanka

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Self-consistent extraction of photoabsorption time delays in attosecond streak camera

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Science China(Physics,Mechanics & Astronomy) 2024年第12期67卷 8-16页

作者： Yutong Gao Hongcheng Ni Andreas becker Jian Wu State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China JILA and Department of Physics University of ColoradoBoulder 80309-0440USA Chongqing Key Laboratoryof PrecisionOptics Chongqing Institute of East China Normal UniversityChongqing 4112China

Photoionization can generally be decomposed into a photoabsorption process plus a half-scattering *** streaking time delay observed in the attosecond streak camera,correspondingly,can be decomposed into a photoabsorption time delay and a continuum time *** propose a self-consistent method to account for the potential-laser coupling effect and extract the intrinsic absorption time delay,without invoking an implicit assumption of a constant continuum correction made in previous streaking *** concept is based on an iterative technique starting from an initial guess of the absorption time delay and using classical electron trajectories to consistently remove the coupling-induced momentum shift to the streak *** show that the self-consistent iterative algorithm converges quickly and is robust against different initial *** method is applied to laser-induced ionization of atoms to obtain the absorption time delay in resonant two-photon ionization and to explore possible time delays in above-threshold *** results confirm an absorption time delay linearly dependent on the ionizing pulse duration in resonant two-photon *** method is also shown to perform better than conventional methods and to identify a small negative absorption time delay(less than 2 attoseconds) in above-threshold ionization.

关键词： attosecond streak camera photoabsorption time delay photoionization

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Spatially simplified scatterplots for large raster datasets

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Geo-Spatial Information Science 2016年第2期19卷前插1-前插1,81-93页

作者： Bin Li Daniel A.Griffith Brian becker Department of Geography College of Science and EngineeringCentral Michigan UniversityMount PleasantMIUSA School of Economic Political and Policy SciencesUniversity of Texas at DallasRichardsonTXUSA

Scatterplots are essential tools for data exploration. However, this tool poorly scales with data-size, with overplotting and excessive delay being the main problems. Generalization methods in the attribute domain focus on visual manipulations, but do not take into account the inherent nature of information redundancy in most geographic data. These methods may also result in alterations of statistical properties of data. Recent developments in spatial statistics, particularly the formulation of effective sample size and the fast approximation of the eigenvalues of a spatial weights matrix, make it possible to assess the information content of a georeferenced data-set, which can serve as the basis for resampling such data. Experiments with both simulated data and actual remotely sensed data show that an equivalent scatterplot consisting of point clouds and fitted lines can be produced from a small subset extracted from a parent georeferenced data-set through spatial resampling. The spatially simplified data subset also maintains key statistical properties as well as the geographic coverage of the original data.

关键词： Scatterplot spatial autocorrelation effective sample size

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