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Glaciation-induced features or sediment gravity flows——An analytic review

Journal of Palaeogeography 2023年第4期12卷 487-545页

作者： Mats O.Molen Umea FoU ab Vallmov 61S-90352 Ume aSweden

For more than 150 years, geologic characteristics claimed to be evidence for pre-Pleistocene glaciations have been debated. Advancements in recent decades, in understanding features generated by mainly glacial and mass flow processes, are here reviewed. Detailed studies of data offered in support of prePleistocene glaciations have led to revisions that involve environments of mass movements. Similarities and differences between Quaternary glaciogenic and mass movement features are examined, to provide a more systematic methodology for analysing the origins of more ancient deposits. Analyses and evaluation of data are from a) Quaternary glaciogenic sediments, b) formations which have been assigned to pre-Pleistocene glaciations, and c) formations with comparable features associated with mass movements(and occasionally tectonics). Multiple proxies are assembled to develop correct interpretations of ancient strata. The aim is not per se to reinterpret specific formations and past climate changes, but to enable data to be evaluated using a broader and more inclusive conceptual *** occurring pre-Pleistocene features interpreted to be glaciogenic, have often been shown to have few or no Quaternary glaciogenic equivalents. These same features commonly form by sediment gravity flows or other non-glacial processes, which may have led to misinterpretations of ancient deposits. These features include, for example, environmental affinity of fossils, grading, bedding, fabrics, size and appearance of erratics, polished and striated clasts and surfaces(“pavements”), dropstones, and surface *** decades of progress in research relating to glacial and sediment gravity flow processes have resulted in proposals by geologists, based on more detailed field data, more often of an origin by mass movements and tectonism than *** most coherent data of this review, i.e., appearances of features produced by glaciation, sediment gravity flows and a fe

关键词： Diamictite Tillite Sediment gravity flow(SGF) Striation Groove Dropstone Paleoclimate Fossil vegetation Glaciogenic proxies Surface microtexture Late Paleozoic ice age

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On the Performance of Active Analog Self-Interference Cancellation Techniques for Beyond 5G Systems

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China Communications 2021年第10期18卷 158-168页

作者： Haifeng Luo Mark Holm Tharmalingam Ratnarajah Institute for Digital Communications School of EngineeringThe University of EdinburghEdinburghUK Huawei Technologies(sweden)ab GothenburgSweden

The in-band full-duplex(IBFD)mechanism is of interest in beyond 5 G systems due to its potential to enhance spectral efficiency and reduce *** achieve the maximum gain of IBFD systems,the significant self-interference(SI)must be efficiently *** challenges of wideband selfinterference cancellation(SIC)lie in the radio frequency(RF)domain,where the performance will be limited by the *** paper reviews current RF cancellation mechanisms and investigates an efficient mechanism for future wideband systems with minimum *** working principle and implementation details of multi-tap cancellers are first introduced,then an optical domain-based RF canceller is reviewed,and a novel low-cost design is *** minimize the cost and complexity of the canceller,the minimum required number of taps are *** results show that with the commonly used 12-bits analog-to-digital converter(ADC)at the receiver,the novel optical domain-based canceller can enable efficient SIC in the 3 GPP LTE specifications compatible system within 400 MHz bandwidth.

关键词： full-duplex beyond 5G system self-interference cancellation optical domain-based canceller

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Experimental analysis of tip vortex cavitation mitigation by controlled surface roughness

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Journal of Hydrodynamics 2020年第6期32卷 1059-1070页

作者： Urban Svennberg abolfazl Asnaghi Robert Gustafsson Rickard E.Bensow Kongsberg Hydrodynamic Research Centre Kongsberg Maritime ABKristinehamnSweden Department of Mechanics and Maritime Sciences Chalmers University of TechnologyGothenburgSweden

This study presents results of experiments where roughness applications are evaluated in delaying the tip vortex cavitation inception of an elliptical ***-speed video recordings and laser doppler velocimetry(LDV)measurements are employed to provide further details on the cavitation behavior and tip vortex flow properties in different roughness pattern *** angular momentum measurements of the vortex core region at one chord length downstream of the tip indicate that roughness leads to a lower angular momentum compared with the smooth foil condition while the vortex core radius remains similar in the smooth and roughened *** observations show that the cavitation number for tip vortex cavitation inception is reduced by 33%in the optimized roughness pattern compared with the smooth foil condition where the drag force increase is observed to be around 2%.During the tests,no obvious differences in the cavitation inception properties of uniform and non-uniform roughness distributions are ***,the drag force is found to be higher with a non-uniform roughness distribution.

关键词： Roughness tip vortex mitigation cavitation suppression

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Mapping of decentralised photovoltaic and solar thermal systems by remote sensing aerial imagery and deep machine learning for statistic generation

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Energy and AI 2023年第4期14卷 559-577页

作者： Johan Lindahl Robert Johansson David Lingfors Becquerel sweden ab SE-74142 KnivstaSweden Department of Engineering Sciences Uppsala UniversitySE-75121 UppsalaSweden

As a mean to monitor the rapid expansion of the highly decentralized PV market,identifying solar energy systems in aerial imagery by deep machine learning,is a research field that is getting increasing *** general challenge in the field is to create testing data of high quality that are representative of the end-use *** this study we use the open source convolutional neural network developed within the DeepSolar project and apply it in the country of sweden,for the purpose of generating market statistics,by scanning three complete municipalities for small decentralized photovoltaic and solar thermal *** evaluation of the performance is done against a highly accurate ground truth,which was created by cross-checking the classification results with the inventory of the local distribution system operators and the database of photovoltaic systems that have received a capital subsidy in sweden,and combining that with physical onsite inspections.A process of generate additional training data and re-training the algorithm after each municipality scan was developed,which suc-cessively improved the accuracy,resulting in that 95%of all detectable photovoltaic,excluding building inte-grated and vertical systems,and 80%of all detectable solar thermal systems were correctly identified in the last municipality *** accurate ground truth allowed a quantification of why some systems are not *** generated dataset of solar energy systems could be connected to existing building and property inventories,which allowed creation of market segment statistics with remarkably high detail information.

关键词： Photovoltaics Solar thermal Aerial imagery Remote sensing Object recognition Convolutional neural networks

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Influence of morphology on high-temperature rheological properties of bitumen modified with styrene-butadiene-styrene(SBS)copolymer

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Frontiers of Structural and Civil Engineering 2021年第3期15卷 806-819页

作者： Jiqing ZHU Xiaohu LU Swedish National Road and Transport Research Institute(VTI) Linköping SE-58195Sweden Nynas ab Nynäshamn SE-14982Sweden

Different microstructures of the same polymer-modified bitumen(PMB)were obtained by subjecting the bitumen modified with styrene-butadiene-styrene(SBS)copolymer to isothermal annealing at various *** effects of the morphology on the rheological properties of SBS-modified bitumen were investigated within the hightemperature *** PMB microstructures were quantitatively evaluated using image analysis.A dynamic shear rheometer was used to measure the rheological parameters of the PMB samples and perform the multiple stress creep and recovery(MSCR)test.A quantitative basis could be established on which to discuss the relationship between the PMB morphology and *** image analysis indicated that conditioning by isothermal annealing evidently led to a difference in the microstructure of the *** of the thermal history is demonstrated to be a practical way to vary the morphology of the PMB with the same raw materials and *** with the two-phase morphology,the single-phase microstructure tended to have a narrower linear viscoelastic(LVE)region of the *** the LVE region,especially at low frequencies,the homogenous PMB can store more energy when experiencing loadings and is more *** the LVE region,based on the MSCR test results,the homogenous morphology could assist in reaching a higher percentage of strain recovery after the creep period.

关键词： polymer bitumen microstructure rheology viscoelasticity

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Ca^(2＋) involvement in activation of extracellular-signal- regulated-kinase 1/2 and m-calpain after axotomy of the sciatic nerve

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Neural Regeneration Research 2017年第4期12卷 623-628页

作者： Lisa B. Martensson Charlotta Lindwall Blom Lars B. Dahlin Department of Translational Medicine-Hand Surgery Lund UniversityMalmoSweden Cellectricon ab MolndalSweden Department of Hand Surgery Skane University HospitalMalmoSweden

Detailed mechanisms behind regeneration after nerve injury, in particular signal transduction and the fate of Schwann cells （SCs）, are poorly understood. Here, we investigated axotomy-induced activation of extracellular- signal-regulated kinase-1/2 （ERK1/2; important for proliferation） and m-calpain in vitro, and the relation to Ca2＋ deletion and Schwann cell proliferation and death after rat sciatic nerve axotomy. Nerve segments were cultured for up to 72 hours with and without ethylene glycol-bis（β-aminoethyl ether）- N,N,N＇,N＇-tetraacetic acid （EGTA）. In some experiments, 5-bromo-2′-deoxyuridine （BrdU） was added during the last 24 hours to detect proliferating cells and propidium iodide （PI） was added at the last hour to detect dead and/or dying cells. Immunohistochemistry of sections of the cultured nerve segments was performed to label m-calpain and the phosphorylated and activated form of ERK1/2. The experiments revealed that immunoreactivity for p-ERK1/2 increased with time in organotypically cultured SCs. p-ERK1/2 and m-calpain were also observed in axons. A significant increase in the number of dead or dying SCs was observed in nerve segments cultured for 24 hours. When deprived of Ca2＋, activation of axonal m-calpain was reduced, whereas p-ERK1/2 was increased in SCs. Ca2＋ deprivation also significantly reduced the number of proliferating SCs, and instead increased the number of dead or dying SCs. Ca2＋ seems to play an important role in activation of ERK1/2 in SCs and in SC survival and proliferation. In addition, extracellular Ca2＋ levels are also required for m-calpain activation and up-regulation in axons. Thus, regulation of Ca2＋ levels is likely to be a useful method to promote SC proliferation.

关键词： nerve regeneration p-ERK1/2 m-calpain nerve injury signal transduction cell proliferation cell death activation axotomy sciatic nerve neural regeneration

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Direct GHG emissions from a pilot scale MBR-process treating municipal wastewater

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Advances in Climate Change Research 2022年第1期13卷 138-145页

作者： Christian BARESEL Jingjing YANG Niclas BORNOLD Kare TJUS Linda KANDERS Klara WESTLING IVL Swedish Environmental Research Institute ab Valhallavagen 81Stockholm 10031Sweden

To evaluate direct greenhouse gas emissions from Membrane Biological Reactor(MBR),measurements of nitrous oxide(N_(2)O)and methane(CH_(4))were made at a pilot-scale MBR treating municipal wastewater Measurements were conducted during two campaigns with some changes in processes,*** a pre-aeration tank in the second measurement,different distributions of aeration in the treatment line,not the same wastewater inflow rate,two types of ultrafiltration *** was found that about 0.004% and 0.07% of the total ammonium loads were emitted as N_(2)O,CH_(4) emissions were 0.026% and 0.12% of incoming TOC(0.008% and 0.04% of incoming COD)in 2014 and *** obtained N_(2)O emission values were relatively *** study suggested that a high aeration at the beginning of the treatment line may result in significantly high emissions of both N_(2)O and CH_(4).A significant change in aeration in the membrane ultrafiltration tank did not have the same *** MBR process is known for high quality effluent but have been questioned due to its higher carbon footprint due to energy *** study gave a reference case about direct GHG emissions from MBR process and provide information for the further evaluation of MBR processes.

关键词： Greenhouse gases(GHGs) Nitrous oxide(N_(2)O) Methane(CH_(4)) Membrane biological reactor(MBR)

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Solution strengthened ferritic ductile iron ISO 1083/JS/500-10 provides superior consistent properties in hydraulic rotators

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China Foundry 2009年第4期6卷 343-351页

作者： Richard Larker Indexator ab Box 11 S-922 21 Vindeln Sweden

Consistent mechanical and machining properties are essential in many applications where ductile irons offer the most cost-effective way to produce structural *** the production of hydraulic rotators,dimensional tolerances are typically 20μm to obtain designated *** castings where intermediate strength and ductility is required,it is common knowledge that conventional ferritic-pearlitic ductile irons such as ISO 1083/500-7 show large hardness *** are mainly caused by the notoriously varying pearlite content,both at different locations within a part and between parts in the same or different *** rate variations due to different wall thickness and position in the molding box,as well as varying amounts of pearlite-stabilizing elements,all contribute to detrimental hardness *** obvious remedy is to avoid pearlite formation,and instead obtain the necessary mechanical properties by solution strengthening of the ferritic matrix by increasing silicon content to 3.7wt%-3.8wt%.The Swedish development in this field 1998 resulted in a national standardization as SS 140725,followed in 2004 by ISO 1083/ JS/*** ab decided 2005 to specify JS/500-10 for all new ductile iron parts and to convert all existing *** include reduction by 75%in hardness variations and increase by 30%in cutting tool life,combined with consistently better mechanical properties.

关键词： ferritic ductile irons ferritic-pearlitic ductile irons properties hydraulic rotators solutionstrengthening

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Static/dynamic friction and wear of some selected polymeric materials for conformal tribo-pairs under boundary lubrication conditions

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Friction 2013年第3期1卷 232-241页

作者： Daniel NILSSON Braham PRAKASH Bosch Rexroth Mellansel ab MellanselSweden Division of Machine Elements Department of Engineering Sciences and MathematicsLuleåUniversity of TechnologyLuleåSweden

This work is aimed at investigating the friction and wear performance of different polymeric materials having potential for hydraulic system components under lubricated sliding conditions against a steel counter face.A pin-on-disc test configuration was used for the experimental *** different polymeric materials selected for these studies were commercial polyimides(PI),polyether ether ketone(PEEK),and *** of these materials were bulk materials whereas others were used as coatings applied on to the cast iron *** tribological characteristics of the polymers were compared with a reference grey cast *** frictional characteristics were evaluated in both static and dynamic *** results have shown that by using polymeric materials it is possible to reduce breakaway friction by an order of magnitude compared to grey cast ***,the breakaway friction increased significantly after the wear *** polymeric materials having lowest breakaway friction have shown the highest wear with the exception of the PEEK-PTFE coating which showed low *** with graphite fillers also showed low wear but it resulted in relatively high *** carbon fibre reinforced materials resulted in unstable friction as well as higher wear compared to the PI materials with graphite fillers.

关键词： polymer tribology static friction dynamic friction and lubricated wear

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A predictive chance constraint rebalancing approach to mobility-on-demand services

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Communications in Transportation Research 2023年第1期3卷 107-117页

作者： Sten Elling Tingstad Jacobsen Anders Lindman Balázs Kulcsár Department of Electrical Engineering Chalmers University of TechnologyGothenburg41258Sweden Volvo Cars ab Gothenburg41878Sweden

This paper considers the problem of supply-demand imbalances in Mobility-on-Demand(MoD)*** imbalances occur due to uneven stochastic travel demand and can be mitigated by proactively rebalancing empty vehicles to areas where the demand is *** achieve this,we propose a method that takes into account uncertainties of predicted travel demand while minimizing pick-up time and rebalance mileage for autonomous MoD *** precisely,first travel demand is predicted using Gaussian Process Regression(GPR)which provides uncertainty bounds on the *** then formulate a stochastic model predictive control(MPC)for the autonomous ride-hailing service and integrate the demand predictions with uncertainty *** order to guarantee constraint satisfaction in the optimization under estimated stochastic demand prediction,we employ a probabilistic constraining method with user-defined confidence interval,using Chance Constrained MPC(CCMPC).The benefits of the proposed method are ***,travel demand uncertainty prediction from data can naturally be embedded into the MoD optimization framework,allowing us to keep the imbalance at each station below a certain threshold with a user-defined ***,CCMPC can be relaxed into a Mixed-Integer-Linear-Program(MILP)and the MILP can be solved as a corresponding Linear-Program,which always admits an integral *** transportation simulations show that by tuning the confidence bound on the chance constraint,close to optimal oracle performance can be achieved,with a median customer wait time reduction of 4%compared to using only the mean prediction of the GPR.

关键词： Mobility-on-Demand Travel demand uncertainty Fleet optimization Gaussian process regression Chance constraint optimization Energy efficiency

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