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International Journal of Digital Earth 2014年第3期7卷 194-216页

作者： Alata Elatawneh Chariton Kalaitzidis George P.Petropoulosc thomas schneider Institute of Forest Management Technische Universität Muünchen(TUM)85354 FreisingGermany Department of Geoinformation in Environmental Management Mediterranean Agronomic Institute of Chania(MAICh)Chania 73100Greece INFOCOSMOS 13341 AthensGreece

Information on Earth’s land surface cover is commonly obtained through digital image analysis of data acquired from remote sensing *** this study,we evaluated the use of diverse classification techniques in discriminating land use/cover types in a typical Mediterranean setting using Hyperion *** this purpose,the spectral angle mapper(SAM),the object-based and the non-linear spectral unmixing based on artificial neural networks(ANNs)techniques were applied.A further objective had been to investigate the effect of two approaches for training sites selection in the SAM classification,namely of the pixel purity index(PPI)and of the direct selection of training points from the Hyperion imagery assisted by a QuickBird imagery and field-based training *** classification outperformed the other techniques with an overall accuracy of 83%.Sub-pixel classification based on the ANN showed an overall accuracy of 52%,very close to that of SAM(48%).SAM applied using the training sites selected directly from the Hyperion imagery supported by the QuickBird image and the field visits returned an increase accuracy by 16%.Yet,all techniques appeared to suffer from the relatively low spatial resolution of the Hyperion imagery,which affected the spectral separation among the land use/cover classes.

关键词： Hyperion Earth’s land use/cover mapping digital image analysis spectral angle mapper sub-pixel classification artificial neural networks Greece

Tunable sharp and highly selective microwave-photonic band-pass filters based on stimulated Brillouin scattering

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Photonics Research 2014年第4期2卷 18-25页

作者： Yonatan Stern Kun Zhong thomas schneider Ru Zhang Yossef Ben-Ezra Moshe Tur Avi Zadok Faculty of Engineering Bar-Ilan UniversityRamat-Gan 5290002Israel Beijing University of Post and Telecommunications Beijing 100876China Institut für Hochfrequenztechnik Hochschule für TelekommunikationD-04277 LeipzigGermany Faculty of Engineering Holon Institute of Technology52 Golomb St.Holon 5810201Israel School of Electrical Engineering Faculty of EngineeringTel-Aviv UniversityTel-Aviv 6997801Israel

Stimulated Brillouin scattering(SBS)in optical fibers has long been used in frequency-selective optical signal processing,including in the realization of microwave-photonic(MWP)*** this work,we report a significant enhancement in the selectivity of SBS-based MWP *** having a single passband of 250 MHz–1 GHz bandwidth are demonstrated,with selectivity of up to 44 *** selectivity of the filters is better than that of the corresponding previous arrangements by about 15 *** shape factor of the filters,defined as the ratio between their−20 dB bandwidth and their−3 dB bandwidth,is between 1.35 and *** central transmission frequency,bandwidth,and spectral shape of the passband are all independently *** enhancement is based on two advances,compared with previous demonstrations of tunable SBS-basedMWPfilters:(a)the polarization attributes of SBS in standard,weakly birefringent fibers are used to discriminate between in-band and out-of-band components and(b)a sharp and uniform power spectral density of the SBS pump waves is synthesized through external modulation of an optical carrier by broadband,frequency-swept *** signal-to-noise ratio of filtered radio-frequency waveforms and the linear dynamic range of the filters are estimated analytically and quantified ***,a figure of merit for the performance of the filters is proposed and *** filters are applicable to radio-over-fiber transmission systems.

关键词： filters scattering polarization

Sharp tunable and additional noise-free optical filter based on Brillouin losses

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Photonics Research 2018年第2期6卷 132-137页

作者： CHENG FENG STEFAN PREUSSLER AND thomas schneider Institut fur Hochfrequenztechnik Technische Universitat Braunschweig 38106 Braunschweig Germany

In this paper, we propose an additional noise-free, independent center frequency and bandwidth tunable optical filter based on stimulated Brillouin scattering(SBS) losses. By suppressing the out-of-band signal with two broadened symmetric SBS losses, tunable pass bandwidths from 500 MHz to 9.5 GHz and the independent center frequency tunability are demonstrated. Considering the limited SBS interaction in the center frequency range,a flat-top response with minimum 0.3 dB ripple is achieved. Assisted by the extra suppression from polarization pulling, a maximum selectivity of 20 dB and an ultrahigh 250 dB∕GHz roll-off are reached. A gain-based SBS filter adds noise to the filtered signal. However, for our proposed filter setup, no additional noise is detected due to the transparency in the passband. Considering the wide independent bandwidth and center frequency tunability, flat-top response, and low-noise characteristic, our proposed filter can be perfectly used as a supplement of most commercialized conventional tunable optical single bandpass filters, whose minimum bandwidth is limited by 10 GHz.

关键词： (290.5900) Scattering, stimulated Brillouin (230.2285) Fiber devices and optical amplifiers (120.2440) Filters.

Brillouin-scattering-induced transparency enabled reconfigurable sensing of RF signals

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Photonics Research 2021年第8期9卷 1486-1492页

作者： JAFFAR KADUM RANJAN DAS ARIJIT MISRA thomas schneider THz-Photonics Group Technische Universitat BraunschweigSchleinitzstraβe 2238106 BraunschweigGermany

Real-time spectrum sensing is essential to enable dynamic and rapid spectrum sharing of unused frequencies to cater the substantial demands of new wireless services deploying the existing RF *** this paper,we present a novel,real-time spectrum sensing approach for widely used RF signals based on Brillouin-scattering-induced transparency(BIT).A temporal discrimination of multi-channel input frequencies is achieved through the group delay tuning by *** tuning the pump power and frequency,the proposed technique is fully reconfigurable and viable for a broad range of spectrum *** experimental illustrations of the time domain sensing are presented for two-tone channels with 0.9,1.8,and 5 GHz frequencies to detect the unused spectrum within 3 G,4 G,and 5 G signals.

关键词： scattering tuning reconfigurable

Femoral Access with Ultrasound-Guided Puncture and Z-Stitch Hemostasis for Adults with Congenital Heart Diseases Undergoing Electrophysiological Procedures

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Congenital Heart Disease 2024年第1期19卷 85-92页

作者： Fu Guan Matthias Gass Florian Berger Heiko schneider Firat Duru thomas Wolber Arrhythmia and Electrophysiology Division Department of CardiologyUniversity Heart Center ZurichZurichSwitzerland Children’s Research Center Zurich University Children’s HospitalZurichSwitzerland Center for Integrative Human Physiology University of ZurichZurichSwitzerland

Aims:Although the application of ultrasound-guided vascular puncture and Z-stitch hemostasis to manage femoral access has been widely utilized,there is limited data on this combined application in adult congenital heart disease(ACHD)patients undergoing electrophysiological(EP)*** sought to evaluate the safety and efﬁcacy of ultrasound-guided puncture and postprocedural Z-stitch hemostasis for ACHD patients under-going EP *** and Results:The population of ACHD patients undergoing transfemoral EP pro-cedures at the University of Zurich Heart Center between January 2019 and December 2022 was observed and *** the study period,femoral access(left/right,arterial/venous)was performed under real-time ultrasound *** the end of the procedure,a single Z-stitch was performed at the puncture *** eval-uated the incidence of in-hospital complications associated with femoral access puncture in this *** 101 patients who had a total of 147 previous ipsilateral vascular punctures(mean 1.5 per person),100 patients underwent successful femoral vascular access for EP *** median age of the patients was 47±15 years and 34(34%)were male.Z-stitches were performed after the procedure in 100 patients with 303 femoral vascular accesses(mean 3 punctures per person).No patient developed vascular puncture relevant inguinal hematoma,pseudo aneurysm,arteriovenousﬁstula,venous or arterial ***:In ACHD patients undergoing EP procedures,optimal femoral access management can be achieved with ultra-sound-guided puncture and postprocedural Z-stitch hemostasis.

关键词： Congenital heart disease cardiac electrophysiology cardiac catheterization femoral access hemostasis

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用铣床直接加工涡轮叶片

世界制造技术与装备市场 2003年第2期 142-143,145页

作者： thomas schneider 杨春林

在自由表面的精加工中,优化五轴联动铣削的应用需要新的CAM功能。应用新的铣削方法,也就是P铣削,所取得的初步经验表明,由于优化了精加工工艺,已在透平叶片的生产中得到了所期望的成果。以下是阐述这一新方法的报告。

关键词：五轴联动数控铣床涡轮叶片数控加工 CAM

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古代埃及的死亡观与丧葬

南方文物 2018年第1期 40-45,12页

作者：托马斯·施耐德高伟(翻译) 不详中国社会科学院考古研究所

2016年12月13日上午．加拿大英属哥伦比亚大学的埃及学家托马斯·施耐德教授在中国社会科学院考古研究所开始了其埃及系列考古讲座的第三讲，题目为“古代埃及的死亡与丧葬”。本讲座由中国社会科学院考古研究所副所长陈星灿研究员主持... 详细信息

2016年12月13日上午．加拿大英属哥伦比亚大学的埃及学家托马斯·施耐德教授在中国社会科学院考古研究所开始了其埃及系列考古讲座的第三讲，题目为“古代埃及的死亡与丧葬”。本讲座由中国社会科学院考古研究所副所长陈星灿研究员主持。来自中国社会科学院考古研究所、中国社会科学院世界历史研究所、北京师范大学、首都师范大学、中央美术学院单位的老师和学生们聆听了本次讲座。以下是本次讲座的主要内容。

关键词：古代埃及死亡观中国社会科学院丧葬历史研究所哥伦比亚大学北京师范大学首都师范大学

Crystal Structure Refinement: A Crystallographer's Guide to SHELXL

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Insights into carbon dioxide sequestration into coal seams through coupled gas flow-adsorption-deformation modelling

丛书名： IUCr texts on crystallography

2006年

作者： Peter Müller Regine Herbst-Irmer Anthony L. Spek thomas R. schneider Michael R. Sawaya

ISBN: (数字)9780191718809

ISBN: (纸本)9780198570769

This book covers advanced aspects of practical crystal structure refinement, focusing on practical problems in the everyday life of a crystallographer. After an introduction to SHELXL in the first chapter, the second chapter provides a brief survey of crystal structure refinement. The next few chapters address the various aspects of structure refinement, from the treatment of hydrogen atoms to the assignment of atom types, to disorder, to non-crystallographic symmetry and twinning. One chapter is dedicated to the refinement of macromolecular structures and two shorter chapters deal with structure validation. In most chapters, the book gives refinement examples, based on the program SHELXL, describing every problem in detail.

关键词： crystal structure determination SHELXL refinement hydrogen atoms atom types disorder twinning pseudo-symmetry artefacts structure validation crystal structure determination SHELXL refinement hydrogen atoms atom types disorder twinning pseudo-symmetry artefacts structure validation

来源：畅想之星图书光盘版（南... 评论

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 26-40页

作者： Hywel thomas Min Chen Geoenvironmental Research Centre Cardiff School of EngineeringCardiff UniversityQueen’s BuildingsThe ParadeNewport RoadCardiffCF243AAUK Key Laboratory of Marine Geology Tongji UniversityShanghai200092China

Injecting carbon dioxide(CO_(2))into coal seams may unlock substantial carbon sequestration *** the coal acts like a carbon filter,it can preferentially absorb significant amounts of CO_(2).To explore this further,desorption of the adsorbed gas due to pressure drop is investigated in this paper,to achieve an improved understanding of the long-term fate of injected CO_(2) during post-injection *** paper presents a dual porosity model coupling gas flow,adsorption and geomechanics for studying coupled processes and effectiveness of CO_(2) sequestration in coals.A new adsorption?desorption model derived based on thermodynamics is incorporated,particularly,the desorption hysteresis is *** reliability of the proposed adsorption-desorption isotherm is examined via validation *** is indicated that occurrence of desorption hysteresis is attributed to the adsorption-induced pore *** injection ceases,the injected gas continues to propagate further from the injection well,while the pressure in the vicinity of the injection well experiences a significant *** the adsorbed gas near the well also decreases,this decrease is less compared to that in pressure because of desorption *** unceasing spread of CO_(2) and drops of pressure and adsorbed gas depend on the degree of desorption hysteresis and heterogeneity of coals,which should be considered when designing CO_(2) sequestration into coal seams.

关键词： CO_(2)geological storage Coal seam Adsorption Desorption hysteresis

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 *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** 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 *** 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