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Static-based early-damage detection using symbolic data analysis and unsupervised learning methods

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Frontiers of Structural and Civil Engineering 2015年第1期9卷 1-16页

作者： Joao Pedro SANTOS Christian CREMONA Andre D. ORCESI Paulo SILVEIRA Luis CALADO Department of Structures Av. Brasil 101 Lisbon 1700-066 Portugal Technical Center for Bridge Engineering CEREMA B.P. 214 Provins Cedex 77487 France Materials and Structures Department IFSTTAR University Paris-Est 14-20 Boulevard Newton Champs sur Marne Marne la Vallee Cedex2 F-77447 France Department of Civil Engineering Technical University Lisbon Avenida Rovisco Pais Lisbon 1096 Portugal

A large amount of researches and studies hav. been recently performed by applying statistical and machine learning techniques for vibration-based damage detection. However, the global character inherent to the limited number of modal properties issued from operational modal analysis may be not appropriate for early-damage, which has generally a local character. The present paper aims at detecting this type of damage by using static SHM data and by assuming that early-damage produces dead load redistribution. To achieve this objective a data driven strategy is proposed, consisting of the combination of advanced statistical and machine learning methods such as principal component analysis, symbolic data analysis and cluster analysis. From this analysis it was observed that, under the noise levels measured on site, the proposed strategy is able to automatically detect stiffness reduction in stay cables reaching at least 1%.

关键词： structural health monitoring early-damage detection principal component analysis symbolic data symbolic dissimilarity measures cluster analysis numerical model damage simulations

Foregut duplication cysts of the stomach with respiratory epithelium

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World Journal of Gastroenterology 2007年第8期13卷 1279-1281页

作者： Theodosios Theodosopoulos Athanasios Marinis Konstantinos Karapanos Georgios Vassilikostas Nikolaos Dafnios Lazaros Samanides Εleni Carνounis 2nd Department of Surgery Areteion University Hospital 76 Vasilisis Sofias av. Athens 11528 Greece Department of Pathology Areteion University Hospital 76 Vasilisis Sofias av. Athens 11528 Greece

Gastrointestinal duplication is a congenital rare disease entity. Gastric duplication cysts seem to appear even more rarely. Herein, two duplications cysts of the stomach in a 46 year-old female patient are presented. Abdominal computed tomography demonstrated a cystic lesion attached to the posterior aspect of the gastric fundus, while upper gastrointestinal endoscopy was negative. An exploratory laparotomy revealed a non-communicating cyst and a smaller similar cyst embedded in the gastrosplenic ligament. Excision of both cysts along with the spleen was performed and pathology reported two smooth muscle coated cysts with a pseudostratified ciliated epithelial lining (respiratory type).

关键词： Gastric Cyst Foregut Duplication Respiratory

Green ionic metal-organic frameworks as nanocatalysts for CO_(2)fixation

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Nano Research 2025年第1期18卷 260-269页

作者： Nuria Martín Miguel Maireles-Porcar Julián Sánchez Velandia Belén Altav. Francisco G.Cirujano Eduardo García-Verdugo Departamento de Química Inorgánica y Orgánica Universidad Jaume IAv.Sos Baynats/nCastellóde la PlanaCastellón 12071Spain

Co,Ni,and Zn iso-reticular coordination polymers of 2,5-dihydroxyterphthalic acid(H_(2)dot)can be rapidly obtained under room temperature and aqueous conditions using either sodium or ammonium hydroxide as the bases to deprotonate the *** use of metal bromides and tetrabutylammonium hydroxide(TBAOH)as the base allows the green synthesis of ionic metal-organic frameworks(MOFs),characterized by X-ray diffraction(XRD),Fourier transform infrared(FTIR),scanning electron microscopy(SEM),thermo grav.metric analysis(TGA),H-nuclear magnetic resonance(NMR),elemental analysis,and X-ray photoelectron spectroscopy(XPS),and employed in the pressure,solvent,and additive-free CO_(2)fixation to epoxides by its cycloaddition to epichlorohydrin,exhibiting a cooperative behav.or between the MOF and the ionic liquid formed within the framework,achieving TONs of the confined tetrabutylammonium bromide(TBABr)up to 700.

关键词： metal-organic frameworks(MOFs) ionic liquids heterogeneous catalysis CO_(2)conversion

Right colon and liver hemangiomatosis:A case report and a review of the literature

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World Journal of Gastroenterology 2006年第39期12卷 6405-6407页

作者： Athanasios Marinis Evi Kairi Theodosios Theodosopoulos Agathi Kondi-Pafiti Vassilios Smyrniotis 2nd Department of Surgery Areteion University Hospital 76 Vasilisis Sofias av. Athens 11528 Greece Department of Pathology Areteion University Hospital 76 Vasilisis Sofias av. Athens 11528 Greece

Cav.rnous hemangiomatosis of the colon and liver in a 38-year-old woman presenting with a history of cramp like abdominal pain and a mass in the right iliac fossa are presented. Abdominal ultrasonography and computed tomography demonstrated multiple liver hemangiomas as well as a noncystic lesion in the right iliac fossa. Operative findings were suggestive of diffuse hemangiomatosis of the right colon and an extensive right hemicolectomy was performed. A review of the literature is presented, considering current diagnostic and therapeutic methods.

关键词： Hemangiomatosis Right Colon Liver

Thin Film Nanocomposites for Gas Sensors

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稀有金属材料与工程 2006年第A3期35卷 33-35页

作者： E.S.Rembeza S.I.Rembeza B.M.Sinelnikov T.V.Svistova E.P.Domashevskaya Voronezh State University University sq.1394006 VoronezhRussia Voronezh State Technical University Moscow av.14394026 VoronezhRussia North Caucasian State Technical University Kulakov av.2355029 StavropolRussia

Nanocomposites on the base of thin films SnO_2 with additives of metal oxides such as SiO_2,ZrO_2,MnO_2 and others,were prepared by reactive ion-beam sputtering of metal target in the ambient of O_2+At,and then thermal treated at 500℃.Atomic composition and morphology of thin film nanocomposites were *** properties and gas sensitivity of nanocomposites were *** Was determined that the grain size of polycrystals depends on the film composition and can run down to 10 *** was found that temperature of maximal gas sensitivity of the films depends on their composition as well and it can be decreased by 100℃～150℃lower than temperature of maximal sensitivity of undoped films SnO_2.

关键词： nanocomposites metal oxides morphology electrical-physical properties gas sensitivity

Radiotherapy-customized head immobilization masks:from modeling and analysis to 3D printing

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Nuclear Science and Techniques 2019年第9期30卷 103-118页

作者： M.A.R.Loja D.S.Crav.iro L.Vieira E.Sousa J.A.Rodrigues R.J.F.Portal CIMOSM Centro de Investigacao em Modelacao e Optimizacao de Sistemas Multifuncionais ISEL IPL Instituto Superior de Engenharia de Lisboa Av. Conselheiro Emidio Navarro 1 1959-007 Lisbon Portugal LAETA IDMEC Instituto Superior Teccnico Universidade de Lisboa Av. Rovisco Pais 1 1049-001 Lisbon Portugal Department of Mechanical and Industrial Engineering Faculty of Science and Technology NOVA UNIDEMI Universidade Nova de Lisboa Caparica Portugal H&TRC -Health &Technology Research Center ESTeSL - Escola Superior de Tecnologia da Saude de Lisboa Av. D. Joao II Lote 4.69.01 1990-096 Lisbon Portugal Instituto de Biofisica e Engenharia Biomedica Faculdade de Ciencias da Universidade de Lisboa Lisbon Portugal

Immobilization devices may be a valuable aid to ensure the improved effectiveness of radiotherapy treatments where constraining the movements of specific anatomical segments is crucial. This need is also present in other situations, specifically when the superposition of various medical images is required for fine identification and characterization of some pathologies. Because of their structural characteristics, existing head immobilization systems may be claustrophobic and very uncomfortable for patients, during both the modeling and usage stages. Because of this, it is important to minimize all the discomforts related to the mask to alleviate patients’ distress and to simultaneously guarantee and maximize the restraint effectiveness of the mask. In the present work, various head immobilization mask models are proposed based on geometrical information extracted from computerized tomography images and from 3D laser scanning point clouds. These models also consider the corresponding connection to a radiotherapy table, as this connection is easily altered to accommodate various manufacturers’ solutions. A set of materials used in the radiotherapy field is considered to allow the assessment of the stiffness and strength of the masks when submitted to typical loadings.

关键词： Computed tomography 3D laser scanning Geometric modeling Head immobilization devices Stiffness and strength analyses 3D printing

The Brio System with Initial Conditions Involving Dirac Masses: A Result Afforded by a Distributional Product

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Chinese Annals of Mathematics,Series B 2014年第6期35卷 941-954页

作者： C.O.R.SARRICO CMAF University of LisbonAv. Prof. Gama Pinto 2 1649-003LisboaPortugal

The Brio system is a 2 × 2 fully nonlinear system of conservation laws which arises as a simplified model in the study of plasmas. The present paper offers explicit solutions to this system subjected to initial conditions containing Dirac masses. The concept of a solution emerges within the framework of a distributional product and represents a consistent extension of the concept of a classical solution. Among other features, the result shows that the space of measures is not sufficient to contain all solutions of this problem.

关键词： Products of distributions Brio's system δ-Shock wav.s δ-Shock wav.s Riemann problem

Assessment of k–ε models using tetrahedral grids to describe the turbulent flow field of a PBT impeller and validation through the PIV technique

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Chinese Journal of Chemical Engineering 2018年第5期26卷 942-956页

作者： Victor X. Mendoza-Escamilla Alejandro Alonzo-Garcia Helvio R. Mollinedo Israel Gonzalez-Neria J. Antonio Yanez-Varela Sergio A. Martinez-Delgadillo Depto. Electronica Universidad Autonoma Metropolitana Azcapotzalco Av. San Pablo 180 Azcapotzalco CP 07740 Mexico D.F. Mexico CONACyT-Centro de Ingenierfa y Desarrollo Industrial Av. Piaya Pie de la Cuesta 702 Desarrollo San Pablo 76125 Queretaro Qro. Mexico UPIITA Instituto Politecnico Nacional Av. IPN 2580 G.A. Madero CP 07340 Mexico D.F. Mexico Depto. Ciencias Basicas Universidad Autonoma Metropolitana Azcapotzalco Av. San Pablo 180 Azcapotzalco CP 07740 Mexico D.F Mexico

In turbulence modeling, the RNG and Realizable models hav. important improvements in the turbulent production and dissipation terms in comparison to the Standard. The selection of the appropriate turbulence model has an impact on the convergence and solution in STRs, and they are used in mixing, multiphase modeling or as starting solution of transient models as DES and LES. Although there are several studies with the pitched blade turbine(PBT) impeller, most of them used the Standard model as representative of all k–ε models, using structured hexahedral grids composed of low number of cells, and in some cases under axial symmetry ***, in this work the assessment of the Standard, RNG and Realizable models to describe the turbulent flow field of this impeller, using the Multiple Reference Frame(MRF) and Sliding Mesh(SM) approaches with tetrahedral domains in dense grids, is presented. This kind of cell elements is especially suitable to reproduce complex geometries. Flow velocities and turbulent parameters were verified experimentally by PIV and torque measurements. The three models were capable of predicting fairly the pumping number, the power number based on torque, and velocities. Although the RNG improved the predictions of the turbulent kinetic energy and dissipation rate, the Realizable model presented better performance for both approaches. All models failed in the prediction of the total dissipation rate, and a dependence of its value on the number of cells for the MRF was found.

关键词： Tetrahedral grids PIV Turbulent flow k-ε models Stirred vessel

Cladophora mats in a Crimean hypersaline lake:structure,dynamics,and inhabiting animals

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Journal of Oceanology and Limnology 2018年第6期36卷 1930-1940页

作者： Alexandr V.PRAZUKIN Elena V.ANUFRIIEVA Nickolai V.SHADRIN The A.O.Kovalevsky Institute of Marine Biological Research of RAS 2 Nakhimov Av.Sevastopol 299011Russia

Filamentous green algae play an important functional role in element cycling and productivity in the diff erent water bodies. In hypersaline lakes and lagoons of the Crimea, filamentous green algae are present and form bottom and floating mats that occupy large areas with high biomass, up to 4–5 kg(wet biomass)/m2. Cladophora spp. dominated in those mats. Five species of filamentous green algae(Chlorophyta) in Lake Chersonesskoye: C ladophora vadorum(Aresch.) Kütz., C. siwaschensis C. Meyer, C. echinus(Biasol.) Kütz., Ulothrix implexa(Kütz.) Kütz., Rhizoclonium tortuosum(Dillw.) Kütz., and seagrass(Angiospermae) R uppia cirrhosa(Petagna) Grande were found. Cladophora spp. and R. cirrhosa were found in the lake throughout the year, other types of algae were encountered episodically. In most cases the biomass of bottom mat exceeded that of the floating mat. In general, the total biomass of the bottom and floating mats in the lake areas at depths up to 30 cm was in a stable range of values from 100 to 290 mg(dry weight)/cm2. Animal and infusorian av.rage abundance in mats reach high values: infusorians—up to 15 000 000 ind./m2, Cletocamptus retrogressus(Copepoda, Harpacticoida)—up to 730 000 ind./m2, Eucypris mareotica(Ostracoda)—up to 91 000 ind./m2 and Chironomidae larvae(Insecta, Diptera)—up to 140 ind./m2. Those values were much higher than in the plankton.

关键词： green algae mats hypersaline lake photosynthesis invertebrates