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航空电磁方法

世界地质 1982年第2期 212-230页

作者： a.becker 朱仁学

过去的十年巳经看到了在航空电磁(AEM)测量技术中的许多较大的技术进展。虽然1967年以前对基本的航空电磁系统的许多方面进行了改进,以致使资料质量得到很大提高,但在这以后加拿大的航空测量工业应用了多频和多道方法,减小了噪声和漂移... 详细信息

过去的十年巳经看到了在航空电磁(AEM)测量技术中的许多较大的技术进展。虽然1967年以前对基本的航空电磁系统的许多方面进行了改进,以致使资料质量得到很大提高,但在这以后加拿大的航空测量工业应用了多频和多道方法,减小了噪声和漂移水平,并且增加了航空电磁仪器的接收频带宽度,很自然地由于采用了数字记录,所以能利用许多先进的资料整理和解释方法。

关键词：航空电磁矿床穿透深度航空测量导体矿藏超导态摄影测量导电体电磁系统航空电磁测量

基于主成分分析的编译错误信息分类法（英文）

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计算机教育 2016年第8期 37-44页

作者： Brett a.becker Catherine Mooney The Beijing Dublin International College School of Computer Science University College Dublin The Physiology and Medical Physics Department Royal College of Surgeons

成为一个有能力的程序员,对于所有计算学科的学生来说,至关重要,尤其是软件工程专业。程序员初学者面临着很多挑战,例如计算科学专业学生就业率的下滑,以及越来越多的非计算科学专业的学生开始学习程序开发。对于帮助学生识别风险、规... 详细信息

成为一个有能力的程序员,对于所有计算学科的学生来说,至关重要,尤其是软件工程专业。程序员初学者面临着很多挑战,例如计算科学专业学生就业率的下滑,以及越来越多的非计算科学专业的学生开始学习程序开发。对于帮助学生识别风险、规划职业生涯的方法的研究已经进行了几十年了。大多数此类研究主要关注如何分类初学者犯的错误,以帮助他们明白这些错误如何产生,帮助他们快速地克服或回避此类错误。本文展现了如何借助主成分分析方法对编译错误进行分类。我们根据学生在编程过程中产生的数据,提取相关错误的分类信息,以识别学生们的纠结之处,并给他们提供指导建议。

关键词：编译错误编译错误信息程序员初学者 CS1 错误信息分类 Java编程主成分分析

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航空电磁法

国外地质勘探技术 1983年第7期 42-47页

作者： a.becker 曹慕义

近年来航空电法(AME)的发展成果表现在以下几个力面:降低噪声水平来提高AEM系统的灵敏度和穿透深度;采用多分量接收机来提高确定导体几何形状的能力;同时发射几个频率并作二次场测量,以及改进AEM系统的窗口来确定导体的性

关键词：航空电磁法穿透深度二次场分量吊舱导体电磁法勘探超导态导电体电磁系统 AEM 导电覆盖层

The all-diode-pumped laser system POLARIS——an experimentalist's tool generating ultra-high contrast pulses with high energy

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High Power Laser Science and Engineering 2014年第3期2卷 5-11页

作者： Marco Hornung Hartmut Liebetrau Andreas Seidel Sebastian Keppler Alexander Kessler Jrg Krner Marco Hellwing Frank Schorcht Diethard Klpfel Ajay K.Arunachalam Georg a.becker Alexander Svert Jens Polz Joachim Hein Malte C.Kaluza Helmholtz-Institute Jena Germany Institute of Optics and Quantum Electronics JenaGermany

The development,the underlying technology and the current status of the fully diode-pumped solid-state laser system POLARIS is ***,the POLARIS system delivers 4 J energy,144 fs long laser pulses with an ultra-high temporal contrast of 5 × 1012 for the ASE,which is achieved using a so-called double chirped-pulse amplification scheme and cross-polarized wave generation pulse *** tightly focusing,the peak intensity exceeds 3.5 × 1020 W *** parameters predestine POLARIS as a scientific tool well suited for sophisticated experiments,as exemplified by presenting measurements of accelerated proton ***,an additional amplifier has been added to the laser *** the ramp-up phase,pulses from this amplifier are not yet compressed and have not yet reached the anticipated ***,an output energy of 16.6 J has been achieved so far.

关键词： design high power laser laser amplifiers laser plasmas interaction laser systems modelling optimization ultra-intense ultrashort pulse laser interaction with matter

SPECT心肌灌注成像和冠状动脉钙化评分评价稳定型冠状动脉疾病预后的价值——长期随访研究

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国际医学放射学杂志 2009年第6期 572-573页

作者： C.Uebleis a.becker I.G.P.Cumming C.becker P.Bartenstein 申小明 Department of Nuclear Medicine University of Munich Marchioninistrasse 1581377 MunichGermany

目的评价冠状动脉钙化评分(coronary arterycalcification,CAC)对SPECT心肌灌注成像判断稳定型冠状动脉疾病(coronary artery disease,CAD)者长期预后和生存的附加价值。材料与方法研究方案得到当地临床伦理委员会批准,且所有病人签署... 详细信息

目的评价冠状动脉钙化评分(coronary arterycalcification,CAC)对SPECT心肌灌注成像判断稳定型冠状动脉疾病(coronary artery disease,CAD)者长期预后和生存的附加价值。材料与方法研究方案得到当地临床伦理委员会批准,且所有病人签署知情同意书

关键词：心肌灌注成像 CAC SPECT 冠状动脉疾病稳定型

应用交替球管方位的快速双源CT行动态心肌应力灌注成像的初期研究

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国际医学放射学杂志 2010年第4期 396-397页

作者： F.Bamberg E.Klotz T.Flohr a.becker C.R.becker B.Schmidt 赵芳 Department of Clinical Radiology University of Munich Grosshadern CampusMarchioninistrasse 1581377 MunichGermany

目的详述CT定量模型基础上局部心肌血流量(MBF)的原理,并示范其在活体上的应用。方法双源CT扫描采用动态扫描方案,包括每30s于心电图触发收缩末期交替球管方位获

关键词：双源球管灌注成像心肌 CT

发现有血流动力学意义的冠状动脉狭窄:动态CT心肌灌注成像有额外诊断价值

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国际医学放射学杂志 2011年第6期 577-578页

作者： F.Bamberg a.becker F.Schwarz R.P.Marcus M.Greif F.V.Ziegler 王霁朏 Departments of Clinical Radiology Ludwig-Maximilians UniversityKlinikum GrosshadernMarchioninistrasse 1581377 MunichGermany

目的探讨动态CT心肌灌注成像发现有血流动力学意义的冠状动脉狭窄的可行性,冠状动脉狭窄的血流动力学改变用血流储备分数(fractional flow reserve,FFR)来定义。材料与方法该研究经伦理委员会批准,并获得病人知情同意

关键词：心肌灌注成像血流动力冠状动脉狭窄 CT

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

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