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journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1112-1122页

作者： Rohola Hasanpour jürgen schmitt Yilmaz Ozcelik jamal Rostami Institute for Tunneling and Construction Management Ruhr-University Bochum Department of Civil Engineering Darmstadt University of Applied Science Department of Mining Engineering Hacettepe University Department of Mining Engineering Colorado School of Mines

Severe shield jamming events have been reported during excavation of Uluabat tunnel through adverse geological conditions, which resulted in several stoppages at advancing a single shielded tunnel boring machine(TBM). To study the jamming mechanism, three-dimensional(3D) simulation of the machine and surrounding ground was implemented using the finite difference code FLAC3D. Numerical analyses were performed for three sections along the tunnel with a higher risk for entrapment due to the combination of overburden and geological conditions. The computational results including longitudinal displacement contours and ground pressure profiles around the shield allow a better understanding of ground behavior within the excavation. Furthermore, they allow realistically assessing the impact of adverse geological conditions on shield jamming. The calculated thrust forces, which are required to move the machine forward, are in good agreement with field observations and measurements. It also proves that the numerical analysis can effectively be used for evaluating the effect of adverse geological environment on TBM entrapments and can be applied to prediction of loads on the shield and preestimating of the required thrust force during excavation through adverse ground conditions.

关键词： Single shielded tunnel boring machine(TBM) Numerical modeling Shield jamming Squeezing ground Uluabat tunnel

Prediction of TBM jamming risk in squeezing grounds using Bayesian and artificial neural networks

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journal of Rock Mechanics and Geotechnical Engineering 2020年第1期12卷 21-31页

作者： Rohola Hasanpour jamal Rostami jürgen schmitt Yilmaz Ozcelik Babak Sohrabian Institute for Tunneling and Construction Management Ruhr-University BochumBochumGermany Department of Mining Engineering Colorado School of MinesGoldenUSA Department of Civil Engineering Darmstadt University of Applied ScienceDarmstadtGermany Department of Mining Engineering Hacettepe UniversityAnkaraTurkey Faculty of Mining and Metallurgical Engineering Urmia University of TechnologyUrmiaIran

This study presents an application of artificial neural network(ANN)and Bayesian network(BN)for evaluation of jamming risk of the shielded tunnel boring machines(TBMs)in adverse ground conditions such as squeezing *** analysis is based on database of tunneling cases by numerical modeling to evaluate the ground convergence and possibility of machine *** results of initial numerical analysis were verified in comparison with some case studies.A dataset was established by performing additional numerical modeling of various scenarios based on variation of the most critical parameters affecting shield *** includes compressive strength and deformation modulus of rock mass,tunnel radius,shield length,shield thickness,in situ stresses,depth of over-excavation,and skin friction between shield and *** the dataset,an ANN was trained to predict the contact pressures from a series of ground properties and machine ***,the continuous and discretized BNs were used to analyze the risk of shield *** results of these two different BN methods are compared to the field observations and summarized in this *** developed risk models can estimate the required thrust force in both *** BN models can also be used in the cases with incomplete geological and geomechanical properties.

关键词： Bayesian network(BN) Artificial neural network(ANN) Shielded tunnel boring machine(TBM) jamming risk Numerical simulation Squeezing ground

A force-compensated compliant MEMS-amplifier with electrostatic anti-springs

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Microsystems & Nanoengineering 2023年第3期9卷 235-244页

作者： Philip schmitt Martin Hoffmann Microsystems Technology Ruhr-Universität BochumUniversitätsstr.15044801 BochumGermany

In this paper,an electrostatic compliant mechanical amplifier intended for force-compensated displacement amplification in MEMS sensor applications is ***,mechanical transformers that enhance a small input displacement into a large output displacement generate large forces at the input of the *** microsystem proposed here allows for the reduction and compensation of the input stiffness of the amplifier and any mechanical components connected to it while providing a constant amplification ratio at the same *** amplifying mechanism features bidirectional electrostatic anti-springs enabling the control of the stiffness by applying a constant DC *** electrode design of the anti-springs and its influence on the force-displacement characteristic,the side instability and the maximal displacement are studied through analytical approaches and supported by FEA and by *** on the derived models,a compliant electromechanical amplifier is developed,featuring an amplification ratio of *** this amplifier the initial input stiffness of 422 N/m could be reduced to 6.8 N/m by applying a voltage of 100 *** an additional application,we show how the amplifier can be used as a mechanical force sensor with tuneable sensitivity,where the forces at the input are transformed into large output *** experiments,we show how the sensitivity can be adjusted and increased by a factor of 25 by applying a voltage at the anti-springs.

关键词： amplifier electrostatic spring

Multimodal nonlinear imaging of atherosclerotic plaques differentiation of triglyceride and cholesterol deposits

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journal of Innovative Optical Health Sciences 2014年第5期7卷 114-123页

作者： Christian Matthäus Riccardo Cicchi Tobias Meyer Annika Lattermann Michael schmitt Bernd F.M.Romeike Christoph Krafft Benjamin Dietzek Bernhard R.Brehm Francesco S.Pavone jürgen Popp Leibniz Institute of Photonic Technology(IPHT-jena)Albert Einstein Straβe 9 0T145 JerlaGermany Institute of Physical Chemistry and Abbe Center of PhotonicsFriedrich Schiller University jena Helmholtzweg 407743 JenaGermany National Institute of Optics National Research Council(INO-CNR)Largo E.Fermi 6-50125FlorenceItaly European Laboratory for Non-Linear Spectroscopy(LENS)University of Florence Via Nello Carrara 1-50019 Sesto Fiorentino(Firenze)Italy Clinic for Internal Medicine Jena University Hospital Friedrich-Schiller-UniversityErlanger Allee 10107747 JenaGermany Institute of Pathology Department of Neuropathology Jena University Hospital-Friedrich-Schiller-University Erlanger Allee 1010140 JenaGermany Catholic Clinic-Koblenz Intermal Medicine&Cardiology Rudolf Virchow Str.956073 KoblenzGermany

Cardiovascular diseases in general and atherothrombosis as the most common of its individualdisease entities is the leading cause of death in the developed ***,visualizationand characterization of inner arterial plaque composition is of vital diagnostic interest,especilly for the early recognition of vulnerable *** clinical techniques provide valuablemorphological information but cannot deliver information about the chemicai composition ofindividual ***,spectroscopic imaging techniques have recently drawn consider-able *** on the spectroscopic properties of the individual plaque components,as forinstance diferent types of lipids,the composition of atherosclerotic plaques can be analyzedqualitatively as well as ***,we compare the feasibility of multimodal nonlinearimaging combining,two-photon fluorescence(TPF),coherent anti-Stokes Raman scatering(CARS)and second-hamonic generation(SHG)microscopy to contrast composition and mor-phology of lipid deposits against the surrounding matrix of connective tissue with diffractionlimited spatial *** this contribution,the spatial distribution of major constituents of the arterial wall and atherosclerotic plaques like elastin,collagen,triglycerides and cholesterol can be simultaneously visualized by a combination of nonlinear imaging methods,providing a powerful label-free complement to standard histopathological methods with great potential forin vivo application.

关键词： Nonlinear microscopy Raman spectroscopy atherosclerosis.

Spatial modeling issues in future smart cities

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Geo-Spatial Information Science 2013年第1期16卷 7-12页

作者： Gerhard schmitt Department of Architecture and Future Cities Laboratory ETH ZürichZürichSwitzerlandand ETH CREATESingapore

It is our goal to make today’s and future cities smart,sustainable and *** order to achieve this,it is fundamental to understand how each city works,to formalize the knowledge gained and to apply it to a city model as the base for simulations that can generate future scenarios with a high level of *** nature of this model,which must cover design,qualitative and quantitative aspects,has changed over *** this study,we focus on the role of the spatial dimension and of geometry in a city *** from being a dominating generative force in ancient cities,spatial modeling has developed into an underlying description language for present and future cities to define functions and properties of the city in space and *** example of the stocks and flows model applied to the city depicts where and how spatial modeling influences the design,construction and performance of the future Smart City.

关键词： future cities spatial modeling stocks and flows city models reality-based 3D models

In memoriamWalter joseph Bock—a life dedicated to teaching and research in the biological sciences(20 November 1933-27 january 2022)

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Integrative Zoology 2022年第6期17卷 1215-1218页

作者： Michael schmitt john BUCKERIDGE Universität Greifswald Allgemeine&Systematische ZoologieGreifswaldGermany Professor Emeritus RMIT UniversityMelbourneVictoriaAustralia

Walter joseph Bock(Fig.1)was born in Woodhaven,Queens County,New York,NY(USA),the second of 4 children of Paul and Anne Bock,née *** grew up in a German speaking family who discontinued speaking German only at the outset of *** 1947 to 1951 he attended Brooklyn Technical High School,where there was considerable emphasis on technological *** 1951,he entered Cornell University in Ithaca,NY,graduating with a Bachelor of Science in *** Cornell,he attended a short lecture series presented by the famed ethologist Konrad Lorenz,and began an association with the ornithologist Charles *** links provided Walter with a growing appreciation of the wonders of the world of biology.

关键词： teaching Walter continued

Mitophagy:From the dark into the spotlight

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Molecular Plant 2023年第10期16卷 1487-1489页

作者： Vivian schmitt Olivier Van Aken Department of Biology Lund UniversityLundSweden

Despite the generally placid appearance of plants,many dynamicprocesses take place inside a plant *** such process thathas garnered attention in recent years is termed"autophagy."While originally discovered in yeast,our understanding of autophagy in plants has improved *** is considered a cellular recycling system in which cellular components oreven entire organelles can be encapsulated by a membranestructure(autophagosome)and then transported to the vacuole(in plants)for degradation and re-use.

关键词： attention organelle spite

Molecular dynamics simulation of the Stribeck curve: Boundary lubrication, mixed lubrication, and hydrodynamic lubrication on the atomistic level

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Friction 2023年第12期11卷 2342-2366页

作者： Simon STEPHAN Sebastian schmitt Hans HASSE Herbert M.URBASSEK Laboratory of Engineering Thermodynamics(LTD) Department of Mechanical and Process EngieeringTU KaiserslauternRheinland-Pfalz 67663Germany Physics Department and Research Center(OPTIMAS) TU KaiserslauternRheinland-Pfalz 67663Germany

Lubricated contact processes are studied using classical molecular dynamics simulations for determining the entire range of the Stribeck ***,the lateral movement of two solid bodies at different gap height are *** each simulation,a rigid asperity is moved at constant height above a flat iron surface in a lubricating *** methane and decane are considered as *** three main lubrication regimes of the Stribeck curve and their transition regions are covered by the study:Boundary lubrication(significant elastic and plastic deformation of the substrate),mixed lubrication(adsorbed fluid layer dominates the process),and hydrodynamic lubrication(shear flow is set up between the surface and the asperity).We find the formation of a tribofilm in which lubricant molecules are immersed into the metal surface—not only in the case of scratching,but also for boundary lubrication and mixed *** formation of a tribofilm is found to have important consequences for the contact ***,the two fluids are found to show distinctly different behavior in the three lubrication regimes:For hydrodynamic lubrication(large gap height),decane yields a better tribological performance;for boundary lubrication(small gap height),decane shows a larger friction coefficient than methane,which is due to the different mechanisms observed for the formation of the tribofilm;the mixed lubrication regime can be considered as a transition regime between the two other ***,it is found that the nature of the tribofilm depends on the lubricant:While methane particles substitute substrate atoms sustaining mostly the crystalline structure,the decane molecules distort the substrate surface and an amorphous tribofilm is formed.

关键词： boundary lubrication mixed lubrication hydrodynamic lubrication molecular dynamics simulation tribofilm

Evaluation of quantitative contrast harmonic imaging to assess malignancy of liver tumors:A prospective controlled two-center study

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World journal of Gastroenterology 2007年第47期13卷 6356-6364页

作者： EM jung DA Clevert AG Schreyer S schmitt j Rennert R Kubale S Feuerbach F jung Department of Diagnostic Radiology University Hospital RegensburgFranz-Josef Strauss-Allee 11Regensburg 93043Germany Department of Radiology Ultrasound SectionGroβhadern HospitalLudwig Maximilian University of MunichMarchioninistr15Mnchen 81377Germany Department of Trauma Surgery Passau HospitalInnstraβe 76Passau 94034Germany Institutes of Radiology Nuclear Medicine and UltrasoundPirmasens HospitalGermany Center for Biomaterial Development Institute of Polymer ResearchGKSSKantstr55Teltow 14513Germany

AIM: To establish the extent to which contrast enhancement with SonoVue in combination with quantitative evaluation of contrast-medium dynamics facilitates the detection of hepatic tumors. METHODS: One hundred patients with histologically confirmed malignant or benign hepatic tumor (maximum size 5 cm) were analyzed. Contrast-enhanced ultrasound (bolus injection 2.5 mL SonoVue) was carried out with intermittent breath-holding technique using a multifrequency transducer (2.5-4 MHz). Native vascularization was analyzed with power Doppler. The contrast-enhanced dynamic ultrasound investigation was carried out with contrast harmonic imaging in true detection mode during the arterial,portal venous and late phases. Mechanical index was set at 0.15. Perfusion analysis was performed by post-processing of the raw data time intensity curve (TIC) analysis. The cut-off of the gray value differences between tumor and normal liver tissue was established using Receiver Operating Characteristic (ROC) analysis 64-line multi-slice computed tomography served as reference method in all cases. Magnetic resonance tomography was used additionally in 19 cases. RESULTS: One hundred patients with 59 malignant (43 colon,5 breast,2 endocrine metastases,7 hepatocellular carcinomas and 2 kidney cancers) and 41 benign (15 hemangiomas,7 focal nodular hyperplasias,5 complicated cysts,2 abscesses and 12 circumscribed fatty changes) tumors were included. The late venous phase proved to be the most sensitive for classification of the tumor type. Fifty-eight of the 59 malignant tumors were classified as true positive,and one as false negative. This resulted in a sensitivity of 98.3%. Of the 41 benign tumors,37 were classified as true negative and 4 as false negative,which corresponds to a specificity of 90.2%. Altogether,95.0% of the diagnoses were classified as correct on the basis of the histological classification. No investigator-dependency (P = 0.23) was noted. CONCLUSION: The results show the poss

关键词： Liver tumors Malignant tumor Contrast harmonic imaging Quantitative contrast enhancement

Self-assembled bright luminescent hierarchical materials from a tripodal benzoate antenna and heptadentate Eu(III) and Tb(III) cyclen complexes

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Frontiers of Chemical Science and Engineering 2019年第1期13卷 171-184页

作者： Aramballi j.Savyasachi David F.Caffrey Kevin Byrne Gerard Tobin Bruno D'Agostino Wolfgang schmitt Thorfinnur Gunnlaugsson School of Chemistry and Trinity Biomedical Sciences Institute (TBSI) University of Dublin Trinity College Dublin Dublin 2 Ireland School of Chemistry and Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) University of Dublin Trinity College Dublin Dublin 2 Ireland

The europium heptadentate coordinatively unsaturated (Eu(III)) and the terbium (Tb(III)) 1,4,7,10-tetraazacyclododecane (cyclen) complexes 1 and 2 were used in conjunction with ligand 3 (1,3,5-benzene-trisethynylbenzoate) to form the supramolecular self-assembly structures 4 and 5;this being investigated in both the solid and the solution state. The resulting self-assemblies gave rise to metal centered emission (both in the solid and solution) upon excitation of 3, confirming its role as a sensitizing antenna. Drop-cased examples of ligand 3, and the solid forms of 4 and 5, formed from both organic and mixture of organic-aqueous solutions, were analyzed using Scanning Electron Microscopy, which showed significant changes in morphology;the ligand giving rise to one dimensional structures, while both 4 and 5 formed amorphous materials that were highly dense solid networks containing nanoporous features. The surface area (216 and 119 m2·g^-1 for 4 and 5 respectively) and the ability of these porous materials to capture and store gases such as N2 investigated at 77 K. The self-assembly formation was also investigated in diluted solution by monitoring the various photophysical properties of 3–5. This demonstrated that the most stable structures were that consisting of a single antennae 3 and three complexes of 1 or 2 (e.g., 4 and 5) in solution. By monitoring the excited state lifetimes of the Eu(III) and Tb(III) ions in H2O and D2O respectively, we showed that their hydration states (the q-value) changed from -2 to 0, upon formation of the assemblies, indicating that the three benzoates of 3 coordinated directly to the each of the three lanthanide centers. Finally we demonstrate that this hierarchically porous materials can be used for the sensing of organic solvents as the emission is highly depended on the solvent environment;the lanthanide emission being quenched in the presence of acetonitrile and THF, but greatly enhanced in the presence of methanol.

关键词： self-assembly supramolecular chemistry lanthanides Eu(III) and Tb(III) complexes luminescence metallostars