检索结果-南通市图书馆

Nonlinear Reduced DNN Models for State Estimation

在线全文

学校读者我要写书评

暂无评论

Communications in Computational Physics 2022年第6期32卷 1-40页

作者： wolfgang Dahmen Min Wang Zhu Wang Department of Mathematics University of South CarolinaColumbiaSC 29208USA Department of Mathematics Duke UniversityDurhamNC 27708USA

We propose in this paper a data driven state estimation scheme for generating nonlinear reduced models for parametric families of PDEs, directly providingdata-to-state maps, represented in terms of Deep Neural Networks. A major constituentis a sensor-induced decomposition of a model-compliant Hilbert space warranting approximation in problem relevant metrics. It plays a similar role as in a ParametricBackground Data Weak framework for state estimators based on Reduced Basis concepts. Extensive numerical tests shed light on several optimization strategies that areto improve robustness and performance of such estimators.

关键词： State estimation in model-compliant norms deep neural networks sensor coordinates reduced bases ResNet structures network expansion

A possible important CO_2 sink by the global water cycle

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2008年第3期53卷 402-407页

作者： LIU ZaiHua wolfgang DREYBRODT WANG HaiJing The State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Karst Dynamics Laboratory Ministry of Land and Resources Guilin 541004 China Institute of Experimental Physics University of Bremen Bremen 28334 Germany School of Geographical Sciences Southwest University Chongqing 400715 China

The locations,magnitudes,variations and mechanisms responsible for the global CO2 sink are uncer-tain and under ***,we show,based on theoretical calculations and evidences from field monitoring results,that there is a possible important CO2 sink(as DIC-dissolved inorganic carbon)by the global water *** sink constitutes up to 0.8013 Pg C/a(or 10.1% of the total anthropogenic CO2 emission,or 28.6% of the missing CO2 sink),and is formed by the CO2 absorption of water and subsequent enhanced consumption by carbonate dissolution and aquatic plant *** the sink,0.5188 Pg C/a goes to sea via precipitation over sea(0.2748 Pg C/a)and continental rivers(0.244 Pg C/a),0.158 Pg C/a is released to the atmosphere again,and 0.1245 Pg C/a is stored in the continental aquatic ***,the net sink could be 0.6433 Pg C/*** sink may increase with the global-warming-intensified global water cycle,the increase in CO2 and carbonate dust in atmosphere,and reforestation/afforestation,the latter increasing soil CO2,and thus the concentration of the DIC in water.

关键词：二氧化碳全球水循环碳酸盐分解水生植物光合作用

Development of new classes of plasmon active nano-structures and their application in bio-sensing and energy guiding

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2014年第5期9卷 652-664页

作者： Ondrej Stranik Jacqueline Jatschka Andrea Csaki wolfgang Fritzsche Leibniz Institute of Photonic Technology Jena 07745 Germany

Metal nanostructures exhibit special optical resonance modes originating fronl tile subwavelengt.h confinement of conductive electrons in the material. These resonance modes represent a strong research focus due to their application potential in optics and sensing application, in this short review recent achievements of our group in this field are highlighted. A wet-chemistry approach synthesis of advanced metallic nanostruetures will be introduced and their exact positioning and manipulation by electric field is shown. Next. the application of these nanostructures for a detection of small molecules will be described in several examples. Also, it will be shown that inetal nanostruetures can be used for sub-wavelength light focusing and for efficient energy coupling into polymer chains.

关键词： plasmonics sensing nanostructures fabrication energy guiding

Channel adaptive rate control for energy optimization

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 82-88页

作者： BLANCH Carolina POLLIN Sofie LAFRUIT Gauthier EBERLE wolfgang Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium Interdisciplinary Institute for BroadBand TechnologyGent-Ledeberg B-9050Belgium Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium Interdisciplinary Institute for BroadBand TechnologyGent-Ledeberg B-9050 Belgium Department of Electrical EngineeringK.U.LeuvenESAT/INSYSBelgium Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium

Low energy consumption is one of the main challenges for wireless video transmission on battery limited devices. The energy invested at the lower layers of the protocol stack involved in data communication, such as link and physical layer, represent an important part of the total energy consumption. This communication energy highly depends on the channel conditions and on the transmission data rate. Traditionally, video coding is unaware of varying channel conditions. In this paper, we propose a cross-layer approach in which the rate control mechanism of the video codec becomes channel-aware and steers the instantaneous output rate according to the channel conditions to reduce the communication energy. Our results show that energy savings of up to30% can be obtained with a reduction of barely 0.1 dB on the average video quality. The impact of feedback delays is shown to be small. In addition, this adaptive mechanism has low complexity, which makes it suitable for real-time applications.

关键词： Rate control, Channel condition, Communication energy

Non-Viral Deoxyribonucleoside Kinases——Diversity and Practical Use

在线全文

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2015年第5期42卷 235-248页

作者： Louise Slot Christiansen Birgitte Munch-Petersen wolfgang Knecht Department of Biology Lund University Department of Science Systems and ModelsRoskilde University Lund Protein Production Platform Lund University

Deoxyribonucleoside kinases （dNKs） phosphorylate deoxyribonucleosides to their corresponding monophosphate compounds, dNks also phosphorylate deoxyribonucleoside analogues that are used in the treatment of cancer or viral infections. The study of the mammalian dNKs has therefore always been of great medical interest. However, during the last 20 years, research on dNKs has gone into non- mammalian organisms. In this review, we focus on non-viral dNKs, in particular their diversity and their practical applications. The diversity of this enzyme family in different organisms has proven to be valuable in studying the evolution of enzymes. Some of these newly discovered enzymes have been useful in numerous practical applications in medicine and biotechnology, and have contributed to our understanding of the structural basis of nucleoside and nucleoside analogue activation.

关键词： Nucleosides Nucleotides Nucleoside salvage pathway Evolution Suicide gene therapy Deoxynucleosides Deoxynucleotides Deoxy-nucleoside kinases

High resolution, binder-free investigation of the intrinsic activity of immobilized NiFe LDH nanoparticles on etched carbon nanoelectrodes

在线全文

学校读者我要写书评

暂无评论

Nano Research 2018年第11期11卷 6034-6044页

作者： Patrick Wilde Stefan Barwe Corina Andronescu wolfgang Schuhmann Edgar Ventosa Analytical Chemistry - Center for Electroche.mical Sciences (CES) Ruhr-Universitat Bochum Universitasstr. 150 D-44780 Bochum Germany IMDEA Energy Avda. Ramo de la Sagra 3 28935 Motoles Spain

The determination of the intrinsic properties of nanomaterials is essential for their optimization as electrocatalysts, however it poses great challenges from the standpoint of analytical tools and methods. Herein, we report a novel methodology that allows for a binder-free investigation of electrocatalyst nanoparticles. The potential-assisted immobilization of a non-noble metal catalyst, i.e., nickel-iron layered double hydroxide (NiFe LDH) nanoparticles, was employed to directly attach small nanoparticle ensembles from a suspension to the surface of etched carbon nanoelectrodes. The dimensions of this type of electrodes allowed for the immobilization of the catalyst material below the picogram scale and resulted in a high resolution towards the faradaic current response. In addition the effect of the electrochemical aging on the intrinsic activity of the catalyst was investigated in alkaline media by means of continuous cyclic voltammetry. A change in the material properties could be observed, which was accompanied by a substantial decrease in its intrinsic activity.

关键词： oxygen evolution reaction nickel-iron layered double hydroxide (NiFe LDH) immobilization nanoelectrocatalysis nanoelectrodes nanoimpacts

Particle-Image Velocimetry and Force Measurements of Leading-Edge Serrations on Owl-Based Wing Models

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2014年第3期11卷 423-438页

作者： Andrea Winzen Benedikt Roidl Stephan Klan Michael Klaas wolfgang Schroder Institute of Aerodynamics RWTH Aachen University Aachen Germany

High-resolution Particle-Image Velocimetry （PIV） and time-resolved force measurements were performed to analyze the impact of the comb-like structure on the leading edge of barn owl wings on the flow field and overall aerodynamic performance. The Reynolds number was varied in the range of 40,000 to 120,000 and the range of angle of attack was 0° to 6° for the PIV and -15° to ＋20° for the force measurements to cover the full flight envelope of the owl. As a reference, a wind-tunnel model which possessed a geometry based on the shape of a typical barn owl wing without any owl-specific adaptations was built, and measurements were performed in the aforementioned Reynolds number and angle of attack： range. This clean wing model shows a separation bubble in the distal part of the wing at higher angles of attack. Two types of comb-like structures, i.e., artificial serrations, were manufactured to model the owl＇s leading edge with respect to its length, thickness, and material properties. The artificial structures were able to reduce the size of the separation region and additionally cause a more uniform size of the vortical structures shed by the separation bubble within the Reynolds number range investigated, resulting in stable gliding flight independent of the flight velocity. However, due to increased drag coefficients in conjunction with similar lift coefficients, the overall aerodynamic performance, i.e., lift-to-drag ratio is reduced for the serrated models. Nevertheless, especially at lower Reynolds numbers the stabilizing effect of the uniform vortex size outperforms the lower aerodynamic performance.

关键词： leading-edge serrations particle-image velocimetry owl-based wing models

Interpreting Morphologically Homogeneous(Paleo-)Populations as Ecological Species Enables Comparison of Living and Fossil Organism Groups,Exemplified by Nummulitid Foraminifera

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Earth Science 2022年第6期33卷 1362-1377页

作者： Johann Hohenegger Ana Ivis Torres-Silva wolfgang Eder Institute for Paleontology University of Vienna1090ViennaAustria

Morphologically homogeneous groups,either living populations or fossil paleo-populations,must be regarded as ecological species,independent of their molecular genetic resemblance in living *** is always expressed during development by structure genes initiated from a network of regulator genes acting at different times and intensities,additionally being subjected to epigenetic ***,homogeneous populations influenced by the environment represent species better than the reproduction(biological species)or molecular-genetic approach using ancestral sequences like *** and fossil representatives of nummulitid foraminifera were chosen to demonstrate complete reconstruction of morphology using metrical growth-invariant and growth-independent *** these characters,6 models were established to define ecological species in living and fossil ***,a distinction between evolutionary and environmental effects in fossil forms was possible using discriminant analysis showing characters that are responsible for differentiating between evolutionary and environmental trends.

关键词： ecological species growth-invariant metrical characters morphology homogeneity nummulitids

Overlap of concurrent extrahepatic autoimmune diseases is associated with milder disease severity of newly diagnosed autoimmune hepatitis

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2021年第1期20卷 21-27页

作者： Tobias Mühling Helmut Rohrbach wolfgang Schepp Felix Gundling Department of Gastroenterology Internal Medicine ⅡUniversity of WürzburgWürzburgGermany Department of Pathology Academic Teaching Hospital BogenhausenTechnical University of MunichMunich 81925Germany Department of Gastroenterology Hepatology and Gastrointestinal OncologyAcademic Teaching Hospital BogenhausenTechnical University of MunichMunich 81925Germany Department of Internal Medicine Division of GastroenterologyGastrointestinal Oncology and DiabetologyKemperhof KoblenzKoblenzGermany

Background:Concurrent extrahepatic autoimmune disorders(CEHAID)are frequently observed in autoimmune hepatitis(AIH).It is not clear whether there is any prognostic significance of CEHAID on *** aim of this study was to examine the prognostic impact of CEHAID and the correlation with the disease severity of ***:This study included 65 hospitalized subjects who fulfilled the accepted criteria for AIH during an 8-year period(2009–2016).All records were manually screened for presence of associated autoimmune *** severity of AIH was assessed by liver laboratory tests including the ratio of aspartate aminotransferase to alanine aminotransferase(AST/ALT)and liver ***:Among the enrolled patients,52(80%)were female(median age 61 years,IQR 45–75).Fifty-six(86.2%)were classified as type-1 *** 26(40%)patients at least one additional extrahepatic autoimmune disease was ***-four subjects were referred to our hospital because of acute presentation of AIH(supposed by an acute elevation of hepatic enzymes)for subsequent liver biopsy resulting in initial diagnosis of *** group was stratified into 3 subgroups:(A)AIH alone(n=14);(B)overlap with primary biliary cirrhosis(PBC)/primary sclerosing cholangitis(PSC)(n=11);and(C)with CEHAID(n=9).AST/ALT ratio was the lowest in subgroup C(median 0.64,IQR 0.51–0.94;P=0.023),compared to subgroup A(median 0.91,IQR 0.66–1.10)and subgroup B(median 1.10,IQR 0.89–1.36).Patients with AIH alone showed a trend to the highest grade of fibrosis(mean 2.3;95%CI:1.5–3.0)with no statistical significance compared to subjects with CEHAID(lowest grade of fibrosis;mean 1.5;95%CI:0.2–2.8;P=0.380)whereas the ongoing inflammation was ***:AST/ALT ratio and extent of fibrosis were lower in subjects with AIH and CEHAID,compared to subjects with only ***,the occurrence of CEHAID might be a predictor for lower disease severity of newly diagnosed acute onset AIH,possibly caused by an e

关键词： Autoimmune hepatitis Concurrent extrahepatic autoimmune disease Serum aminotransferase activities