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爆破器材 1982年第4期 44-45页

作者： k.r.becker J.E.Hay E.A.Day 瞿增禧美国矿山局匹兹堡研究中心

一、引言本文介绍的雷管,由灼热桥丝或热气体源激发后,与下述过程适当配合,即可获得可靠的高阶起爆: 由猛炸药或烟火药组成的“主发装药”着火,并

关键词：雷管焦耳起爆药桥丝击发药主装药延期药柱

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

EVALUATING THE WEIGHTED-SUM APPrOACH FOr MEASUrING BUILDINGS’ADAPTABILITY

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Journal of Green Building 2020年第3期15卷 37-54页

作者： Anna k becker Brandon E.ross Dustin Albright 310A Lowry Hall Clemson UniversityClemsonSC 29634-0911USA.

As urban populations increase worldwide and more demands are placed on infrastructure and buildings,the topic of adaptable building design has experienced increased interest as a way to embed adaptability into the urban building stock and avoid unnecessary demolition and *** tools for judging building adaptability based on physical characteristics have recently been *** most common approach for these tools is to use a weighted-sum of scores for different *** primary purpose of this paper was to compare a weighted-sum measurement approach against a more rigorous,less abstract measurement that involved judgements about simulated adaptation projects(called an example-based approach).These measurements were performed through expert elicitation and an analytic hierarchy process(AHP)survey,where participants evaluated the relative adaptability of four case study buildings from the Clemson University *** results showed significant correlation between the weighted-sum approach and the example-based approach,supporting the reasonableness of using weighted-sum approaches to evaluate the adaptive potential of building *** addition,a separate group of experts rated adaptability of the case study buildings by providing qualitative reasons for their *** the other approaches,this group was not given a specific tool to guide their *** qualitative data provided additional context for understanding results from the quantitative approaches.

关键词： adaptability flexibility sustainability reuse analytic hierarchy process

Agricultural growing season calendars derived from MODIS surface reflectance

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International Journal of Digital Earth 2015年第3期8卷 173-197页

作者： Alyssa k.Whitcraft Inbal becker-reshef Christopher O.Justice Department of Geographical Sciences University of MarylandCollege ParkMDUSA

In order to secure the necessary image acquisitions for global agricultural monitoring applications,we must first articulate Earth observation(EO)requirements for diverse agricultural landscapes and cropping *** to this task is the identification of agricultural growing season timing at a meaningful spatial scale,so as to better define the necessary periods of image *** this end,10 years of MODIS Terra Surface reflectance imagery have been used to determine phenological transition dates including start of season,peak period,and end of season at 0.5°*** is the first set of global,satellite-derived,cropland-specific calendar dates for major field crops within a 0.5°,herein called agricultural growing season calendars Preliminary comparison against ground-based crop-specific calendars is performed,highlighting the utility of this approach for articulating growing season timing and its interannual and within-region *** research provides critical inputs for defining the EO requirements for the Global Agricultural Monitoring initiative(GEOGLAM),an effort by the Group on Earth Observations(GEO)to synergize existing national and regional observation systems for improved agricultural production and food security monitoring.

关键词： agriculture vegetation indices Earth observation data acquisition remote sensing

MicrorNAs in NF-κB signaling

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Journal of Molecular Cell Biology 2011年第3期3卷 159-166页

作者： Xiaodong Ma Lindsey E.becker Buscaglia Juanita r.Barker Yong Li Department of Biochemistry and Molecular Biology School of MedicineUniversity of Louisville319 Abraham Flexner WayLouisvilleKY 40202USA

Nuclear factor κB(NF-κB)is a transcriptional factor that regulates a battery of genes that are critical to innate and adaptive immunity,cell proliferation,inflammation,and tumor ***(mirNAs)are short rNA molecules of 20-25 nucleotides in length that negatively regulate gene expression in animals and plants primarily by targeting 3′untranslated regions of *** this work,we review the convergence of mirNAs and NF-κB signaling and dysregulation of mirNAs and NF-κB activation in human diseases,particularly in *** function of mir-146,mir-155,mir-181b,mir-21,and mir-301a in NF-κB activation and their impact on tumorigenesis are *** that over 1000 human mirNAs have been identified,rendering mirNAs one of the most abundant classes of regulatory molecules,deciphering their biological function and pathological contribution in NF-κB dysregulation is essential to appreciate the complexity of immune systems and to develop therapeutics against cancer.

关键词： microrNA NF-κB cancer

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

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

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

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