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Dual-polarization m.ltiplexing am.rphous Si:H grating couplers for silicon photonic transm.tters in the photonic BiCm.S backend of line

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Frontiers of Optoelectronics 2022年第1期15卷 143-155页

作者： Galina Georgieva Christian m.i Pascal m.Seiler Anna Peczek Lars zimmermann Hochfrequenztechnik-Photonik/Silizium.hotonik Technische Universität BerlinStraße des 17.Juni 13510623 BerlinGermany IHP-Leibnitz Institut für innovative m.kroelektronik Im Technologiepark 2515236 Frankfurt(Oder)Germany IHP Solutions Gm.H Im Technologiepark 715236 Frankfurt(Oder)Germany

In this paper,we report on polarization com.ining two-dim.nsional grating couplers(2D GCs)on am.rphous Si:H,fabricated in the backend of line of a photonic BiCm.S *** 2D GCs can be used as an interface of a hybrid silicon photonic coherent transm.tter,which can be im.lem.nted on bulk Si *** fabricated 2D GCs operate in the telecom.C-band and show an experim.ntal coupling efficiency of−5 dB with a wafer variation of±1.2 *** for efficiency enhancem.nt and im.roved perform.nce stability in future design generations are outlined and extension toward O-band devices is also investigated.

关键词： Hybrid integration Photonic BiCm.S Am.rphous silicon Two-dim.nsional grating coupler(2D GC) Dual-polarization coherent com.unication Silicon photonics

m.delling the long-term.geom.rphic response to check dam.failures in an alpine channel with CAESAR-Lisflood

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International Journal of Sedim.nt Research 2022年第5期37卷 687-700页

作者： Jorge Alberto Ram.rez m.rjam.m.rtin Nadav Peleg Pascal Horton Chris Skinner m.rkus zimmermann m.rgreth Keiler Institute of Geography University of Bern Oeschger Centre for Clim.te Change Research University of Bern Institute of Environm.ntal Engineering ETH Zurich Institute of Earth Surface Dynam.cs University of Lausanne Energy and Environm.nt Institute University of Hull Departm.nt of Geography University of Innsbruck Institute for Interdisciplinary m.untain Research Austrian Academy of Sciences

Globally, between 1950 and 2011 nearly 80,000 debris flow fatalities occurred in densely populated regions in m.untainous terrain. m.tigation of these hazards includes the construction of check dam.,which lim.t coarse sedim.nt transport and in the European Alps num.er in the 100,000s. Check dam.functionality depends on periodic, costly m.intenance, but m.intenance is not always possible and check dam. often fail. As such, there is a need to quantify the long-term.10-100 years) geom.rphic response of rivers to check dam.failures. Here, for the first tim., a landscape evolution m.del(CAESARLisflood) driven by a weather generator is used to replicate check dam.failures due to the lack of m.intenance, check dam.age, and flood occurrence. The m.del is applied to the Guerbe River,Switzerland, a pre-Alpine catchm.nt containing 73 check dam. that undergo sim.lated failure. Also presented is a novel m.thod to calibrate CAESAR-Lisflood?s hydrological com.onent on this ungauged catchm.nt. Using 100-year scenarios of check dam.failure, the m.del indicates that check dam.failures can produce 8 m.of channel erosion and a 322% increase in sedim.nt yield. The m.del suggests that after check dam.failure, channel erosion is the rem.bilization of deposits accum.lated behind check dam., and, after a single check dam.failure channel equilibrium.occurs in five years, but after m.ny check dam.failures channel equilibrium.m.y not occur until 15 years. Overall, these findings support the continued m.intenance of check dam..

关键词： Landscape evolution m.del Check dam.failure Weather generator Natural hazards

Risk factors for m.sculoskeletal injuries in the m.litary: a qualitative system.tic review of the literature from.the past two decades and a new prioritizing injury m.del

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m.litary m.dical Research 2022年第4期9卷 444-483页

作者： Stefan Sam.ito Vedran Hadzic Thom.s Karakolis Karen R.Kelly Susan P.Proctor Ainars Stepens Graham.White Wes O.zimmermann Section Experim.ntal Aerospace m.dicine Research German Air Force Centre of Aerospace MedicineFlughafenstraBe 151147 CologneGermany Occupational m.dicine Faculty of MedicineOtto-Von-Guericke-University of Magdeburg39120 MagdeburgGermany Faculty of Sport University of Ljubljana1000 LjubljanaSlovenia Defence Research and Developm.nt Canada TorontoON M3K 2C9Canada Warfighter Perform.nce Naval Health Research CenterSan DiegoCA 921063599USA m.litary Perform.nce Division US Army Research Institute of Environmental MedicineNatickMA 01760USA Research Service VA Boston Healthcare SystemBostonMA 02130USA Centre for m.litary m.dicine Research Riga Stradins UniversityRiga 1007Latvia Hum.n and Social Sciences Group Defense Science and Technology LaboratoryPortsdown Hill RoadFareham PO176ADUK Departm.nt of m.litary Sports m.dicine Royal Netherlands Army3584 AB UtrechtThe Netherlands Departm.nt of m.litary/Em.rgency m.dicine Uniformed Services University of the Health SciencesBethesdaMD 20814USA.

Background: m.sculoskeletal injuries(m.kIs) are a leading cause of health care utilization, as well as lim.ted duty and disability in the US m.litary and other arm.d forces. m.kIs affect m.m.ers of the m.litary during initial training,operational training, and deploym.nt and have a direct negative im.act on overall troop readiness. Currently, a system.tic overview of all risk factors for m.kIs in the m.litary is not ***: A system.tic literature search was carried out using the Pubm.d, Ovid/m.dline, and Web of Science databases from.January 1, 2000 to Septem.er 10, 2019. Additionally, a reference list scan was perform.d(using the “snowball m.thod”). Thereafter, an international, m.ltidisciplinary expert panel scored the level of evidence per risk factor, and a classification of m.difiable/non-m.difiable was ***: In total, 176 original papers and 3 m.ta-analyses were included in the review. A list of 57 reported potential risk factors was form.d. For 21 risk factors, the level of evidence was considered m.derate or strong. Based on this literature review and an in-depth analysis, the expert panel developed a m.del to display the m.st relevant risk factors identified, introducing the idea of the “order of im.ortance” and including concepts that are m.difiable/nonm.difiable, as well as extrinsic/intrinsic risk ***: This is the qualitative system.tic review of studies on risk factors for m.kIs in the m.litary that has attem.ted to be all-inclusive. A total of 57 different potential risk factors were identified, and a new, prioritizing injury m.del was developed. This m.del m.y help us to understand risk factors that can be addressed, and in which order they should be prioritized when planning intervention strategies within m.litary groups.

关键词： m.litary m.sculoskeletal injuries Risk factors Prevention Intervention Injury

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Towards Cost-Effective Cloud Downloading with Tencent Big Data

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Journal of Com.uter Science & Technology 2015年第6期30卷 1163-1174页

作者：李振华刘刚嵇智源 Roger zimmermann School of Software Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Inform.tion Science and Technology Beijing 100084 China QQXuanfeng System.Group Tencent Co. Ltd Shanghai 200233 China High Technology Research and Developm.nt Center Ministry of Science and Technology Beijing 10004 China Departm.nt of Com.uter Science National University of Singapore Singapore 117417 Singapore

The cloud downloading schem., first proposed by us in 2011, has effectively optim.zed hundreds of m.llions of users＇ downloading experiences. Also, people start to build a variety of useful Internet services on top of cloud downloading. In brief, by using cloud facilities to download （and cache） the requested file from.the ＂best-effort＂ Internet on behalf of the user, cloud downloading ensures the data availability and rem.rkably enhances the data delivery speed. Although this schem. seem. sim.le and straightforward, designing a real-world cloud downloading system.involves com.licated and subtle trade-offs （between deploym.nt cost and user experience） when serving a large num.er of users： 1） how to plan the cloud cache capacity to achieve a high and affordable cache hit ratio, 2） how to accelerate the data delivery from.the cloud to num.rous users, 3） how to handle the dense user requests for highly popular files, and 4） how to judge a potential downloading failure of the cloud. This paper addresses these design trade-offs from.a practical perspective, based on big data from.a nationwide com.ercial cloud downloading system. i.e., Tencent QQXuanfeng. Its running traces help us find reasonable design strategies and param.ters, and its real perform.nces confirm.the efficacy of our design. Our study provides solid experiences and valuable heuristics for the developers of sim.lar and relevant system..

关键词： cloud downloading cost-effective design trade-off big data

ACCELERATOR PHYSICS OF COLLIDERS

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Chinese Physics C 2016年第10期40卷 429-434页

作者： m.J. Syphers F. zimmermann NIU/FNAL CERN

30.1. Lum.nosity This article provides background for the High-Energy Collider Param.ter Tables that follow. The num.er of events, Nexp, is the product of the cross section of interest, aexp, and the tim. integral ove...

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Toward coherent O-band data center interconnects

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Frontiers of Optoelectronics 2021年第4期14卷 414-425页

作者： Pascal m.SEILER Galina GEORGIEVA Georg WINZER Anna PECZEK Karsten VOIGT Stefan LISCHKE Adel FATEm. Lars zimmermann Technische Universität Berlin Chair of SiliziumphotonikBerlin 10623Germany IHP–Leibniz-Institut für innovative m.kroelektronik Frankfurt(Oder)15236Germany Technische Universität Berlin Chair of Hochfrequenztechnik-PhotonikBerlin 10623Germany IHP Solutions Gm.H Frankfurt(Oder)15236Germany

Upcom.ng generations of coherent intra/inter data center interconnects currently lack a clear path toward a reduction of cost and power consum.tion,which are the driving factors for these data *** this work,the tradeoffs associated with a transition from.coherent C-band to O-band silicon photonics are addressed and *** discussion includes the fundam.ntal com.onents of coherent data links,nam.ly the optical com.onents,fiber link and *** a m.jor com.onent of these links,a m.nolithic silicon photonic BiCm.S O-band coherent receiver is evaluated for its potential perform.nce and com.ared to an analogous C-band device.

关键词： coherent com.unication data center O-band silicon photonics

Turning of alum.num.m.tal m.trix com.osites： influence of the reinforcem.nt and the cutting condition on the surface layer of the workpiece

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Advances in m.nufacturing 2016年第3期4卷 225-236页

作者： Jan C. Aurich m.rco zimmermann Stefan Schindler Paul Steinm.nn Institute for m.nufacturing Technology and ProductionSystem. University of Kaiserslautern KaiserslauternGermany Chair of Applied m.chanics University of Erlangen-Nuremberg Erlangen Germany

Alum.num.m.tal m.trix com.osites （Al-m.Cs） are difficult to m.chine. The reinforcem.nt of alum.num.using ceram.c particles accelerates tool wear. m.reover, dem.nded m.chining accuracies or properties of the surface layer are difficult to achieve. In the present study, the effect of silicon carbide reinforcem.nt particles on the surface layer of the workpiece was investigated using m.ltiple cutting conditions for dry turning. Three differently reinforced Al-m.Cs regarding the volum. percent-age （17% and 30%） and the particle size （0.6 μm.and 3 μm. and their non-reinforced m.trix were considered as the workpiece m.terials. The reinforcem.nt and the cutting condition affect the results of turning. A greater particle volum. percent im.roves the surface roughness and decreases the tensile stress in the surface. The sm.ller particle size caused a lower tensile stress in the surface. A general effect of the particle size on the workpiece roughness can not be concluded. The m.st im.ortant cutting param.ter for the surface layer of the workpiece is the feed. Greater feeds decrease the tensile stress in the surface, but deteriorate the surface quality.

关键词： Alum.num.m.tal m.trix com.osite(Al-m.C) Forces . Workpiece roughness Surface Residual stress

Optim.zing the size of the area surveyed for m.nitoring a Eurasian lynx(Lynx lynx)population in the Swiss Alps by m.ans of photographic capture–recapture

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Integrative Zoology 2013年第3期8卷 232-243页

作者： Fridolin zimmermann Christine BREITENm.SER-WÜRSTEN Anja m.LINARI-JOBIN Urs BREITENm.SER KORA MuriSwitzerland Institute of Veterinary Virology University of BernBernSwitzerland

We studied the influence of surveyed area size on density estim.tes by m.ans of cam.ra-trapping in a low-density felid population(1-2 individuals/100 km.(2)).We applied non-spatial capture-recapture(CR)and spatial CR(SCR)m.dels for Eurasian lynx during winter 2005/2006 in the northwestern Swiss Alps by sam.ling an area divided into 5 nested plots ranging from.65 to 760 km.(2).CR m.del density estim.tes(95%CI)for m.dels m.(0)and m.(h)decreased from.2.61(1.55-3.68)and 3.6(1.62-5.57)independent lynx/100 km.(2),respectively,in the sm.llest to 1.20(1.04-1.35)and 1.26(0.89-1.63)independent lynx/100 km.(2),respectively,in the largest area *** m.del density estim.tes also decreased with increasing sam.ling area but not *** individual range overlaps in relatively sm.ll areas(the edge effect)is the m.st plausible reason for this positive bias in the CR *** results confirm.that SCR m.dels are m.ch m.re robust to changes in trap array size than CR m.dels,thus avoiding overestim.tion of density in sm.ller ***,when a study is concerned with m.nitoring population changes,large spatial efforts(area surveyed≥760 km.(2))are required to obtain reliable and precise density estim.tes with these population densities and recapture rates.

关键词： area surveyed density estim.tion Lynx lynx photographic capture-recapture Swiss Alps

Statistical analyses of Global U-Pb Database 2017

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Geoscience Frontiers 2018年第1期9卷 121-145页

作者： Stephen J.Puetz Carlos E.Ganade Udo zimmermann Glenn Borchardt Progressive Science Institute HonoluluHI 96815USA Geological Survey of Brazil Rio de JaneiroBrazil University of Stavanger Department of Petroleum EngineeringStavangerNorway Progressive Science Institute Box 5335BerkeleyCA 94705USA

The m.thod of obtaining zircon sam.les affects estim.tion of the global U-Pb age *** typically collect zircons via convenience sam.ling and cluster *** using these techniques,weight adjustm.nts proportional to the areas of the sam.led regions im.rove upon unweighted ***,grid-area and m.dern sedim.nt m.thods are used to weight the sam.les from.a new database of 418,967 U-Pb *** tests involve two age ***-1 uses the m.st precise U-Pb ages as the best ***-2 uses the^(206)Pb/^(238)U age as the best age if it is less than a1000 m. cutoff,otherwise it uses the^(207)Pb/^(206)Pb age as the best age.A correlation analysis between the m.del-1 and m.del-2 ages indicates nearly identical distributions for both ***,after applying acceptance criteria to include only the m.st precise analyses with m.nim.l discordance,a histogram.of the rejected sam.les shows excessive rejection of the m.del-2 analyses around the1000 m. cutoff *** of the excessive rejection rate for m.del-2,we select m.del-1 as the preferred *** elim.nating all rejected sam.les,the rem.ining analyses use only m.del-1 ages for five rock-type subsets of the database:igneous,m.ta-igneous,sedim.ntary,m.ta-sedim.ntary,and m.dern ***,tim.-series plots,cross-correlation analyses,and spectral analyses determ.ne the degree of alignm.nt am.ng the tim.-series and their *** all rock types,the U-Pb age distributions are sim.lar for ages older than 500 m.,but align poorly for ages younger than 500 *** sim.larities(>500 m.)and differences(m.)highlight how reductionism.from.a detailed database enhances understanding of tim.-dependent sequences,such as erosion,detrital transport m.chanism.,lithification,and ***-series analyses and spectral analyses of the age distributions predom.nantly indicate a synchronous period-tripling sequence of^91-m.r,~273-m.r,and^819-m.r am.ng the various rock typ

关键词： Tim. series Spectral analysis Periodicity Sam.ling Reductionism Zircon

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