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  1. Valutazione degli elementi di struttura e monitoraggio microbiologico nel Comparto operatorio comune del Dipartimento ortopedico dell'Azienda ospedaliera di Parma

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    C. Pasquarella

    2003-05-01

    Full Text Available Obiettivi: scopo di questo studio, che si inserisce nell’ambito di un progetto multicentrico promosso dal Gruppo Italiano Studio Igiene Ospedaliera, è stato quello di valutare le condizioni ambientali e gestionali delle sale operatorie del comparto ortopedico dell’Azienda ospedaliera di Parma. Metodi: l’indagine, svolta nell’ottobre 2002, ha previsto la compilazione di un questionario, riguardante gli aspetti strutturali, impiantistici, organizzativi e gestionali, e l’effettuazione di un monitoraggio microbiologico ambientale nelle diverse aree del blocco operatorio. La carica microbica dell’aria è stata valutata utilizzando piastre di sedimentazione per la rilevazione dell’Indice Microbico Aria (IMA mentre per le superfici sono state impiegate membrane di nitrocellulosa. I campionamenti sono stati effettuati prima dell’inizio e durante l’attività chirurgica. Risultati: i dati ottenuti per mezzo del questionario hanno evidenziato condizioni generalmente buone, sia dal punto di vista strutturale che gestionale del comparto operatorio studiato. Per quanto riguarda il controllo microbiologico, nelle sale operatorie, in tutte le rilevazioni prima dell’attività si sono ottenuti valori di IMA uguali a 0; durante l’attività, si è registrato un valore massimo di IMA di 4 in quelle a flusso laminare e di 19 in quelle con flusso turbolento, al di sotto dei valori limite, rispettivamente di 5 e 25; i valori di contaminazione microbica delle superfici prima dell’attività hanno oscillato da un minimo di 0 ufc/cm2 a un massimo di 0,20 ufc/cm2; durante l’attività, solo in una rilevazione si è registrato un valore di 0,58 ufc/cm2, superiore al valore soglia stabilito. Anche negli altri ambienti del comparto operatorio la contaminazione microbica è risultata complessivamente al di sotto dei limiti di riferimento. Conclusioni: il questionario si è rivelato un valido strumento

  2. Atti del seminario internazionale "Traduzioni e circolazione della letteratura economico-politica nell'Europa settecentesca" (Firenze, Dipartimento di Studi storici e geografici, 20-21 Settembre 2002

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    Niccolò Guasti (a cura di

    2004-01-01

    Full Text Available Niccolò Guasti - Rolando Minuti, Premessa. Antonella Alimento, Le traduzioni progettate, ma mai pubblicate, della Relazione dello stato in cui si trova l'opera del censimento universale dello stato di Milano di Pompeo Neri. Vieri Becagli, Circolazione e diffusione delle traduzioni di testi economici nel '700 italiano: problemi di ricerca. Sandro Landi, Censura e legittimazione del discorso politico. La traduzione toscana dell’ Histoire des Deux Indes dell’abate Raynal. Niccolò Guasti, Il ‘‘ragno di Francia’’ e la ‘‘mosca di Spagna’’: Forbonnais e la riforma della fiscalità all’epoca di Ensenada e Machault. Vicent Llombart, Traducciones españolas de economía política (1700-1812: catálogo bibliográfico y una nueva perspectiva. Jesús Astigarraga, Diálogo económico en la ‘otra’ Europa. Las traducciones españolas de los economistas de la Ilustración napolitana (A. Genovesi, F. Galiani y G. Filangieri. José Miguel Delgado Barrado, La transmisión de escritos económicos en España: el ejemplo de la Erudición política de Teodoro Ventura Argumosa Gándara (1743.

  3. Creazione di valore sanitario e sistemi di finanziamento: il caso del dipartimento di salute mentale

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    Carmine Munizza

    2000-06-01

    Full Text Available Health-value adding is the new priority and a watchword for all clinicians and health service workers. The creation of health-value requires a team work involving different actors: A. the clinical staff, whose task consists in the creation of treatment models and in their formalization into guidelines and protocols; B. the managers, since effective clinical and therapeutic practices must go along with coherent organizational models and valuable control instruments; C. the public institutions responsible for the definition of health policy guidelines: among these, a prioritary role is played by funding methods, which can affect significantly the results of health-value adding initiatives. This work aims at studying the relationships between funding methods and health-value creation, with particular reference to mental health services. Particular relevance is given to the funding of mental health departments, with a view to putting aside the shortcomings of the current models and proposing the DRG as an alternative funding method for mental health services. The procedures for patients classification and evaluation envisaged in the psychiatric DRG can assist health service managers in evaluating the outcomes and the patients’ health conditions. In other words, the issues concerning funding and management evaluation will be articulated in the same language: this, in turn, will eliminate the lack of integration which can be presently identified as the main fault of most funding methods, and improve the degree of coherence among resource allocation, activities and results. The case of mental health services can therefore be taken as an example of successful and effective cooperation among management, health policy and clinical staff.

  4. Programmazione del Network di 'Virologia Ambientale': Stato di avanzamento

    OpenAIRE

    Carlesi, Carlo

    2004-01-01

    Presentazione 'Power Point' dell'intervento all'incontro di lavoro 'VIRAMB II incontro del Network di Virologia Ambientale', presso l'Istituto Zooprofilattico Sperimentale delle Regioni Lazio e Toscana. Nell'intervento si presenta lo stato di avanzamento dei lavori riguardo la realizzazione dell'infrastruttura telematica del 'Network di Virologia Ambientale' promosso dal 'Dipartimento di Patologia Sperimentale, Biotecnologie Mediche, Infettivologia ed Epidemiologia' dell'Universit? di Pisa.

  5. Un'esperienza di didattica integrata: nuove tecnologie e formazione presso la cattedra di Storia delle dottrine politiche

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    Filomena Castaldo

    2004-01-01

    Full Text Available Presentazione di una sperimentazione di blended learning condotta al Dipartimento di Filosofia dell’Universita' “Federico II” di Napoli. L’obiettivo dell’iniziativa e' stato quello di integrare la formazione in presenza con la formazione in rete per collaudare percorsi d’interazione non solo in senso verticale (uno-molti ma anche in orizzontale (molti-molti, con particolare attenzione al processo e alla dimensione sociale dell’apprendimento in rete.

  6. Video e comunicazione scientifica. Il laboratorio MELA dell’Università di Bologna

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    Laura Corazza

    2010-07-01

    Full Text Available Al Media Education e-learning LAboratorio del Dipartimento di Scienze dell’educazione e della Facoltà di Scienze della formazione, Università di Bologna, un gruppo di esperti e di tecnici svolge attività di supporto alla didattica e alla ricerca, lavorando con i docenti per produrre audiovisivi e materiali multimediali. I prodotti MELA sono video per l’approfondimento culturale, per la produzione scientifica, per la documentazione.

  7. Altri collegamenti a lavori del gruppo di DV

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    Doctor Virtualis Redazione

    2008-08-01

    Full Text Available • Giovanni di Mirecourt, Commento alle Sentenze, libro I Attualmente non raggiungibile perché il server del Dipartimento di filosofia è stato oggetto di un attacco da parte di un hacker Edizione provvisoria on-line Il lavoro nasce dalla collaborazione tra Eugenio Randi e Massimo Parodi, e giunge alla pubblicazione on-line (provvisoria grazie all'intervento di Lucia Caccia Dominioni, che ha ordinato e ripulito il materiale a disposizione. • Seminario su Tommaso De ente et essentia - 1995/96 Il materiale prodotto dagli studenti che hanno partecipato al lavoro di discussione seminariale del De ente et essentia di Tommaso d'Aquino.

  8. Particle Image Velocimetry

    DEFF Research Database (Denmark)

    Zhang, Chen; Vasilevskis, Sandijs; Kozlowski, Bartosz

    Particle image velocimetry (PIV) is a non-intrusive, whole filed optical method providing instantaneous velocity information in fluids. The flow is seeded with tracer particles. The particles are illuminated in the target area with a light sheet at least twice within a short time interval....... The camera images the target area and captures each light pulse in separate image frames. The displacement of the particle between the light pulses can be used to determine the velocity vectors. This guideline introduces the principle of the PIV system and the system configuration. The measurement procedure...

  9. Bourgois, F. (2005, Cercando rispetto. Drug economy e cultura di strada, Roma, DeriveApprodi.

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    Giuseppe Scandurra

    2006-01-01

    Full Text Available Philippe Bourgois, professore presso il Dipartimento di Antropologia, Storia e Medicina Sociale dell’Università della California, si trasferisce per cinque anni a East Harem, uno dei ghetti più degradati e malfamati di New York. Qui frequenta spacciatori di crack di origine portoricana, passa il tempo nelle sale sotto casa dove questi ultimi giocano, entra nelle case delle loro famiglie allargate.

  10. Rainbow Particle Imaging Velocimetry

    KAUST Repository

    Xiong, Jinhui

    2017-04-27

    Despite significant recent progress, dense, time-resolved imaging of complex, non-stationary 3D flow velocities remains an elusive goal. This work tackles this problem by extending an established 2D method, Particle Imaging Velocimetry, to three dimensions by encoding depth into color. The encoding is achieved by illuminating the flow volume with a continuum of light planes (a “rainbow”), such that each depth corresponds to a specific wavelength of light. A diffractive component in the camera optics ensures that all planes are in focus simultaneously. With this setup, a single color camera is sufficient to track 3D trajectories of particles by combining 2D spatial and 1D color information. For reconstruction, this thesis derives an image formation model for recovering stationary 3D particle positions. 3D velocity estimation is achieved with a variant of 3D optical flow that accounts for both physical constraints as well as the rainbow image formation model. The proposed method is evaluated by both simulations and an experimental prototype setup.

  11. Analisi sui pigmenti di ceramica neolitica tramite tecniche Raman e LIBS

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    Cristina Fabbri

    2007-04-01

    Full Text Available I dati presentati in questo breve contributo provengono da uno studio condotto in collaborazione dal Dipartimento di Scienze Archeologiche dell’Università di Pisa e dall’Istituto per i Processi Chimico-Fisici di Fisica molecolare del CNR di Pisa. Le metodologie applicate sono basate sull’analisi integrata delle tecniche spettroscopiche Raman e LIBS già ampiamente utilizzate nel campo dei Beni Culturali; i metodi sono infatti essenzialmente non distruttivi, non richiedono di un pre trattamento del campione e l’acquisizione delle misure è immediata.

  12. Optical fibre laser velocimetry: a review

    International Nuclear Information System (INIS)

    Charrett, Thomas O H; James, Stephen W; Tatam, Ralph P

    2012-01-01

    The applications of optical fibre technology to laser velocimetry are diverse and often critical to their successful implementation, particularly in harsh environments. Applications range from the use of optical fibres for beam delivery and scattered light collection, aiding the miniaturization of instrument probes, to the use of imaging fibre bundles for imaging the flow field in planar velocimetry systems. Optical fibre techniques have also been used in signal processing, for example fibre frequency shifters, and optical fibre devices such as amplifiers and lasers have been exploited. This paper will review the use of optical fibres in point-wise laser velocimetry techniques such as laser Doppler velocimetry and laser transit anemometry, as well as in planar measurement techniques such as particle imaging velocimetry and planar Doppler velocimetry. (topical review)

  13. Pierluigi Cuzzolin. Sull'origine della costruzione dicere quod: aspetti sintattici e se­ mantici; Firenze 1994, Pubblicazioni della Facolta di Lettere e Filosofia dell'Università di Pavia, 72, Dipartimento di Lingue e Letterature Straniere Moderne

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    Matjaž Babič

    1995-12-01

    Full Text Available Das Buch ist eine überarbeitete und verbesserte Version der Doktordissertation, die an der Universität von Pavia vorgelegt wurde. Es wird darin ein vielbesprochenes Prob­ lem der lateinischen Sprache erneut aufgegriffen, es wird eine neue Antwort auf die Frage über das Verhaltnis zwischen Accusativus cum infinitivo (Acl und Nebensätzen mit quod/quia dargeboten. Der Accusativus cum infinitivo, regiert von Verben wie 'sagen, denken', gilt als eine Besonderheit des Lateinischen und Altgriechischen im Verhältnis zu den modernen indogermanischen Sprachen. Für den Ursprung und Sinn dieser Infinitivkonstruktion wurden verschiedene Erklärungen vorgeschlagen oder zu­ mindest Richtungen für eine mögliche Lösung angezeigt. Der Verfasser dieses Buches versucht, die vorhandenen Losungen mit Hilfe der allgemeinlinguistischen Erkentnisse zu erganzen und sie in eine neue Lösung zu vereinen.

  14. Volumetric velocimetry for fluid flows

    Science.gov (United States)

    Discetti, Stefano; Coletti, Filippo

    2018-04-01

    In recent years, several techniques have been introduced that are capable of extracting 3D three-component velocity fields in fluid flows. Fast-paced developments in both hardware and processing algorithms have generated a diverse set of methods, with a growing range of applications in flow diagnostics. This has been further enriched by the increasingly marked trend of hybridization, in which the differences between techniques are fading. In this review, we carry out a survey of the prominent methods, including optical techniques and approaches based on medical imaging. An overview of each is given with an example of an application from the literature, while focusing on their respective strengths and challenges. A framework for the evaluation of velocimetry performance in terms of dynamic spatial range is discussed, along with technological trends and emerging strategies to exploit 3D data. While critical challenges still exist, these observations highlight how volumetric techniques are transforming experimental fluid mechanics, and that the possibilities they offer have just begun to be explored.

  15. Edifici di culto e loro pertinenze, consumo del territorio e spending review

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    Federica Botti

    2014-09-01

    Full Text Available assegnista di ricerca nell'Università Alma Mater Studiorum di Bologna, Dipartimento di Scienze GiuridicheContributo sottoposto a valutazione SOMMARIO: 1. Crisi finanziaria dello Stato e nuovo ruolo e funzioni degli edifici di culto - 2. Configurazione degli spazi degli edifici di culto in relazione al loro uso pubblico - 3. Pertinenze “liturgiche” e pertinenze “funzionali”: un primo controllo di spesa - 4. Utilizzazione pubblica delle pertinenze, anche attraverso lo strumento delle convenzioni con gli enti pubblici. Gli edifici di culto di proprietà delle confessioni – 5. Gli edifici di culto di proprietà pubblica gestiti attraverso il F. E. C. -6. Le convenzioni per la concessione dell’utilizzazione a fini di culto di edifici di proprietà pubblica - 7. Il controllo di spesa e il patto di stabilità tra l’attuazione dell’art. 19 Cost., proprietà pubblica di edifici di culto, finanziamenti pubblici per la loro manutenzione/edificazione – 8. Spending review e rivisitazione del rapporto tra consumo del territorio, edifici esistenti e loro utilizzazione/fruizione.

  16. Cathalitic burners for residential gas appliances; Bruciatori catalitici di gas naturale per apparecchi domestici

    Energy Technology Data Exchange (ETDEWEB)

    Accornero, R.; Canci, F. [Italgas Spa, Rome (Italy)

    2000-12-01

    The growing interest for the rational use of natural gas as a primary source of energy and for the reduction of pollutant emissions from combustion processes has kindled, in recent years, a widespread interest in studies and experimental investigations on the use of premix burners (either ceramic or metallic) for heat generators in domestic applications. The present paper deals with the R and D activities developed in this field by Italgas, Politecnico di Torino (Dipartimento di Scienza dei Materiali ed Ingegneria Chimica) and Merloni TermoSanitari, (an Italian gas boiler manufacturer). The technology hereby presented aims at reducing the pollutants emissions (CO, NO{sub x}, HC) in a wide range of working regimes of the burner, typical of residential heat appliances. The positive results in a lab scale experimental pilot plant have been in some cases confirmed in experimental runs performed on boiler prototypes suitable for large scale industrial production. Some projects, financially supported by the European Community and involving, beyond the above mentioned partners, also other gas distribution companies, universities, research institutes and burner manufacturers, are currently in progress to further analyse the performance of these burners. [Italian] Il crescente interesse per l'uso razionale del gas naturale quale fonte energetica primaria e quale combustibile a basso impatto ambientale, ha suscitato, nei tempi piu' recenti, un vasto interesse per gli studi e per le ricerche nel settore dei bruciatori di gas di tipo a premiscelazione, siano essi in materiale ceramico che metallico, allo scopo di rendere praticabile la loro applicazione nei generatori di calore di tipo domestico. L'articolo descrive l'attivita' di R e S sviluppata da Italgas, Politecnico di Torino - Dipartimento di Scienza dei Materiali ed Ingegneria Chimica - e da Merloni TermoSanitari. La tecnologia sperimentata e' finalizzata alla riduzione delle emissioni di

  17. Application of particle imaging velocimetry in windtunnels

    International Nuclear Information System (INIS)

    Kompenhans, J.; Reichmuth, J.

    1987-01-01

    Recently the instantaneous and nonintrusive measurement of the flow velocity in a large area of the flow field (two-dimensional plane) became possible by means of particle imaging velocimetry (PIV). Up to now PIV has mainly been used for model experiments at low flow velocities in order to test and to improve the measuring technique. The present aim is the application of PIV in large wind tunnels at high flow velocities. 7 references

  18. Velocimetry Overview for visitors from the DOD

    Energy Technology Data Exchange (ETDEWEB)

    Briggs, Matthew E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Physics Division; Holtkamp, David Bruce [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Physics Division

    2016-08-19

    We are in the midst of a transformative period in which technological advances are making fundamental changes in the measurement techniques that form the backbone of nuclear weapon certification. Optical velocimetry has replaced electrical shorting pins in “Hydrotests,” which measure the dynamic implosion process. This advance has revolutionized nuclear weapons certification during the last 5 years. We can now measure the implosion process that drives a nuclear detonation with many orders of magnitude more resolution in both space and time than was possible just 10 years ago. It has been compared to going from Morse Code to HDTV, resulting in a dozen or more improvements in models of these weapons. These Hydrotests are carried out at LANL, LLNL and the NNSS, with the later holding the important role of allowing us to test with nuclear materials, in sub-critical configurations (i.e., no yield.) Each of these institutions has largely replaced pins with hundreds of channels of optical velocimetry. Velocimetry is non-contact and is used simultaneously with the X-ray capability of these facilities. The U1-a facility at NNSS pioneered this approach in the Gemini series in 2012, and continues to lead, both in channel count and technological advances. Close cooperation among LANL, LLNL and NSTec in these advances serves the complex by leveraging capabilities across sites and accelerating the pace of technical improvements.

  19. Il progetto Siria: una proposta di archiviazione, ricerca e presentazione dati per Gortina e Mitropolis

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    Isabella Baldini

    2010-03-01

    Full Text Available Il Progetto SIRIA, sviluppato nell’ambito di un progetto strategico del Dipartimento di Archeologia dell'Università di Bologna, è un sistema centralizzato per la gestione, la ricerca e la presentazione della documentazione archeologica. Il sistema è in grado di gestire, all'interno di un database relazionale, le classi di informazioni principali generate dalla ricerca archeologica: dati alfanumerici-tabulari, dati spaziali, immagini e in generale tutti i tipi di file che necessitano di essere archiviati. L'architettura del database, organizzata in un modo flessibile, consente agli utenti di utilizzare, in una struttura comune, gruppi specifici di informazioni (plug-in. L'obiettivo è andare incontro alle istanze dei singoli studiosi permettendo loro di organizzare liberamente i propri dati; inoltre, consentire l’integrazione dei dati e un allargamento della scala di riferimento dei singoli progetti. Il Progetto SIRIA aderisce alla filosofia e agli scopi del movimento open source: il codice è rilasciato sotto la licenza libera software GPLv3.

  20. La leucemia del bambino come causa di disgregazione familiare

    Directory of Open Access Journals (Sweden)

    G. Varchetta

    2003-05-01

    Full Text Available

    Introduzione: le patologie del bambino, soprattutto se gravi e durature, possono essere definite come “malattie della famiglia” a causa dell’intensità di assistenza richiesta, delle difficoltà organizzative quotidiane e dello stress causato. Obiettivo: identificare il ruolo di alcuni potenziali fattori di rischio coinvolti nella rottura di famiglie di bambini leucemici.

    Materiali e metodi: mediante l’uso di questionari, sono state studiate, durante l’anno 2002, 150 cartelle cliniche di bambini leucemici dell’ospedale pediatrico “Santobono-Pausillipon”- Dipartimento di Oncologia; 11 casi sono stati esclusi per incompletezza dei dati. Outcome è stata considerata la “separazione familiare.” Sono state analizzate le seguenti variabili: trapianto di midollo osseo, lavoro del padre, della madre e loro età ed educazione, sesso ed età del bambino (CA, numerosità della famiglia, stato socio-economico, probabilità clinica di guarire (CPR, appartenenza ad una associazione. Sono state condotte analisi bivariate e logistiche. Risultati: all’analisi bivariata CA e CPR, entrambi stratificati in tre livelli, sono risultati associati alla separazione. L’Odds Ratio grezzo (OR della separazione familiare con CA di 5/10 anni e bambini di 11 anni o più a confronto con quelli d’età di 0/4 era, rispettivamente, di 8.68 (p=0.02 e di 5.7 (p=0.07. L’OR grezzo della separazione con un CPR medio e un CPR buono confrontato con un CPR basso ha dato rispettivamente 0.35 (p=0.02 e 0.08 (p‹0.001. Un modello logistico che includeva CPR come variabile principale e controllata per CA ha evidenziato che la probabilità di guarigione è media o alta e, dopo aver aggiustato per l’età del bambino, è stato ottenuto un rischio di rottura familiare rispettivamente di 0.29 (p=0.01 e 0.08 (p=0.02.

    Conclusioni: la rottura dell’unità familiare è evento frequente in caso di grave

  1. Validation and application of Acoustic Mapping Velocimetry

    Science.gov (United States)

    Baranya, Sandor; Muste, Marian

    2016-04-01

    The goal of this paper is to introduce a novel methodology to estimate bedload transport in rivers based on an improved bedform tracking procedure. The measurement technique combines components and processing protocols from two contemporary nonintrusive instruments: acoustic and image-based. The bedform mapping is conducted with acoustic surveys while the estimation of the velocity of the bedforms is obtained with processing techniques pertaining to image-based velocimetry. The technique is therefore called Acoustic Mapping Velocimetry (AMV). The implementation of this technique produces a whole-field velocity map associated with the multi-directional bedform movement. Based on the calculated two-dimensional bedform migration velocity field, the bedload transport estimation is done using the Exner equation. A proof-of-concept experiment was performed to validate the AMV based bedload estimation in a laboratory flume at IIHR-Hydroscience & Engineering (IIHR). The bedform migration was analysed at three different flow discharges. Repeated bed geometry mapping, using a multiple transducer array (MTA), provided acoustic maps, which were post-processed with a particle image velocimetry (PIV) method. Bedload transport rates were calculated along longitudinal sections using the streamwise components of the bedform velocity vectors and the measured bedform heights. The bulk transport rates were compared with the results from concurrent direct physical samplings and acceptable agreement was found. As a first field implementation of the AMV an attempt was made to estimate bedload transport for a section of the Ohio river in the United States, where bed geometry maps, resulted by repeated multibeam echo sounder (MBES) surveys, served as input data. Cross-sectional distributions of bedload transport rates from the AMV based method were compared with the ones obtained from another non-intrusive technique (due to the lack of direct samplings), ISSDOTv2, developed by the US Army

  2. Particle image velocimetry a practical guide

    CERN Document Server

    Raffel, Marcus; Wereley, Steve T; Kompenhans, Jürgen

    2007-01-01

    The development of Particle Image Velocimetry (PIV), a measurement technique, which allows for capturing velocity information of whole ?ow ?elds in fractions of a second, has begun in the eighties of the last century. In 1998, when this book has been published ?rstly, the PIV technique emerged from laboratories to applications in fundamental and industrial research, in par- lel to the transition from photo-graphicalto video recording techniques. Thus this book, whose objective was and is to serve as a practical guide to the PIV technique, found strong interest within the increasing group of us

  3. ABSTRACTS OF THE “GIORNATE DI CONIGLICOLTURA ASIC 2011”

    Directory of Open Access Journals (Sweden)

    ABSTRACTS OF THE “GIORNATE DI CONIG Forlì, Italy,

    2012-10-01

    Full Text Available The fourth edition of the Italian Rabbit Days was held in Forlì (Italy on April 8-9, 2011, organized by ASIC (Italian Rabbit Scientific Association in collaboration with Dipartimento di Scienze degli Alimenti (Università di Bologna, Dipartimento di Scienze Animali (Università di Padova, Fondazione Iniziative Zooprofilattiche e Zootecniche (Brescia, ASPA (Animal Production Scientific Association and the Forli Fair. The first day included three invited lectures: “Feed restriction strategies, implications on physiology, growth and health of the growing rabbit”, presented by T. Gidenne, L. Fortun-Lamothe, S. Combes; “Ovulation induction in rabbit does: a review”, presented by A. Dal Bosco; “Factors affecting efficacy of intravaginal administration of GnRH analogues for ovulation induction in rabbit does” presented by P.G. Rebollar. In addition, three sessions of oral communications on Reproduction and Genetics, Nutrition and Physiology, Welfare, Management, and Pathology were held. During the second day it was presented a round table focused on “Management and use of drugs and vaccines in rabbit production”. Finally a Poster Session was through the two days. The meeting was attended by more than 100 participants, including researchers and technicians from France, Spain, Hungary, Belgium and Switzerland. A total of 3 invited papers, 14 oral communications and 16 posters were presented during the congress. Following the abstracts of all contributions are reported.

  4. 3D scanning particle tracking velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hoyer, Klaus; Holzner, Markus; Guala, Michele; Liberzon, Alexander; Kinzelbach, Wolfgang [Swiss Federal Institut of Technology Zurich, Institut fuer Hydromechanik und Wasserwirtschaft, Zuerich (Switzerland); Luethi, Beat [Risoe National Laboratory, Roskilde (Denmark)

    2005-11-01

    In this article, we present an experimental setup and data processing schemes for 3D scanning particle tracking velocimetry (SPTV), which expands on the classical 3D particle tracking velocimetry (PTV) through changes in the illumination, image acquisition and analysis. 3D PTV is a flexible flow measurement technique based on the processing of stereoscopic images of flow tracer particles. The technique allows obtaining Lagrangian flow information directly from measured 3D trajectories of individual particles. While for a classical PTV the entire region of interest is simultaneously illuminated and recorded, in SPTV the flow field is recorded by sequential tomographic high-speed imaging of the region of interest. The advantage of the presented method is a considerable increase in maximum feasible seeding density. Results are shown for an experiment in homogenous turbulence and compared with PTV. SPTV yielded an average 3,500 tracked particles per time step, which implies a significant enhancement of the spatial resolution for Lagrangian flow measurements. (orig.)

  5. Krypton tagging velocimetry of an underexpanded jet.

    Science.gov (United States)

    Parziale, N J; Smith, M S; Marineau, E C

    2015-06-01

    In this work, we present the excitation/emission strategy, experimental setup, and results of an implementation of krypton tagging velocimetry (KTV). KTV is performed as follows: (i) seed a base flow with krypton; (ii) photosynthesize metastable krypton atoms with a frequency-doubled dye laser to form the tagged tracer; (iii) record the translation of the tagged metastable krypton by imaging the laser-induced fluorescence (LIF) that is produced with an additional dye laser. The principle strength of KTV, relative to other tagging velocimetry techniques, is the use of a chemically inert tracer. KTV results are presented for an underexpanded jet of three mixtures of varying Kr/N2 concentration. It is demonstrated that KTV can be used in gas mixtures of relatively low krypton mole fraction (0.5% Kr/99.5% N2), and the KTV data from that experiment are found to be in good agreement with an empirical fit found in the literature. We find that KTV is useful to perform instantaneous velocity measurements with metastable krypton as a chemically inert, dilute, long-lifetime tracer in gas-phase flows.

  6. Laser doppler velocimetry and confined flows

    Directory of Open Access Journals (Sweden)

    Ilić Jelena T.

    2017-01-01

    Full Text Available Finding the mode, in which two component laser Doppler velocimetry can be applied to flows confined in cylindrical tubes or vessels, was the aim of this study. We have identified principle issues that influence the propagation of laser beams in laser Doppler velocimetry system, applied to flow confined in cylindrical tube. Among them, the most important are influences of fluid and wall refractive indices, wall thickness and internal radius ratio and beam intersection angle. In analysis of the degrees of these influences, we have applied mathematical model, based on geometrical optics. The separation of measurement volumes, that measure different velocity components, has been recognized as the main drawback. To overcome this, we propose a lens with dual focal length – primary focal length for the measurement of one velocity component and secondary focal length for the measurement of the other velocity component. We present here the procedure for calculating the optimal value of secondary focal length, depending on experimental set-up parameters. The mathematical simulation of the application of the dual focal length lens, for chosen cases presented here, confirmed the accuracy of the proposed procedure.

  7. Infanzia e malattie emorragiche congenite. Il punto di vista degli insegnanti attraverso i dati di una ricerca

    Directory of Open Access Journals (Sweden)

    Silvia Demozzi

    2009-07-01

    Full Text Available Il contributo presenta i dati raccolti dalle ricercatrici A. Gigli e S. Demozzi del Dipartimento di Scienze dell’Educazione dell’Università di Bologna per il progetto Strategico di Ateneo “Definizione di linee guida d’intervento sui pazienti pediatrici affetti da malattie emorragiche congenite: aspetti medici, psicosociali, educativi ed etici”. Si tratta dell’analisi di dodici interviste effettuate con insegnanti di scuole della Provincia di Bologna a contatto con bambini/e affetti/e da malattie emorragiche congenite (MEC per capire il loro punto di vista su vari aspetti della vita scolastica e relazionale. I dati sono presentati in relazione alle seguenti aree tematiche: le rappresentazioni degli insegnanti in merito alle malattie emorragiche congenite e le problematiche emergenti dall'incontro con i bambini e le famiglie; la qualità della relazione educativa tra docenti e bambini e del rapporto con le famiglie; la qualità del rapporto del bambino o della bambina con il gruppo dei pari e l'eventualità di una o più attività didattiche differenziate e/o di una programmazione specifica; gli eventuali bisogni formativi ed informativi espressi dagli insegnanti. L’articolo si integra con il lavoro pubblicato da A. Gigli “Una ricerca sulla qualità della vita scolastica di bambini e bambine affetti da malattie emorragiche congenite: lettura critica dei dati e considerazioni pedagogiche” che, con rimando al presente report, si sofferma sull’analisi dei dati raccolti utilizzando riferimenti e categorie specifiche della riflessione pedagogica.

  8. Cryogenic flow rate measurement with a laser Doppler velocimetry standard

    Science.gov (United States)

    Maury, R.; Strzelecki, A.; Auclercq, C.; Lehot, Y.; Loubat, S.; Chevalier, J.; Ben Rayana, F.

    2018-03-01

    A very promising alternative to the state-of-the-art static volume measurements for liquefied natural gas (LNG) custody transfer processes is the dynamic principle of flow metering. As the Designated Institute (DI) of the LNE (‘Laboratoire National de métrologie et d’Essais’, being the French National Metrology Institute) for high-pressure gas flow metering, Cesame-Exadebit is involved in various research and development programs. Within the framework of the first (2010-2013) and second (2014-2017) EURAMET Joint Research Project (JRP), named ‘Metrological support for LNG custody transfer and transport fuel applications’, Cesame-Exadebit explored a novel cryogenic flow metering technology using laser Doppler velocimetry (LDV) as an alternative to ultrasonic and Coriolis flow metering. Cesame-Exadebit is trying to develop this technique as a primary standard for cryogenic flow meters. Currently, cryogenic flow meters are calibrated at ambient temperatures with water. Results are then extrapolated to be in the Reynolds number range of real applications. The LDV standard offers a unique capability to perform online calibration of cryogenic flow meters in real conditions (temperature, pressure, piping and real flow disturbances). The primary reference has been tested on an industrial process in a LNG terminal during truck refuelling. The reference can calibrate Coriolis flow meters being used daily with all the real environmental constraints, and its utilisation is transparent for LNG terminal operators. The standard is traceable to Standard International units and the combined extended uncertainties have been determined and estimated to be lower than 0.6% (an ongoing improvement to reducing the correlation function uncertainty, which has a major impact in the uncertainty estimation).

  9. Objective speckle velocimetry for autonomous vehicle odometry.

    Science.gov (United States)

    Francis, D; Charrett, T O H; Waugh, L; Tatam, R P

    2012-06-01

    Speckle velocimetry is investigated as a means of determining odometry data with potential for application on autonomous robotic vehicles. The technique described here relies on the integration of translation measurements made by normalized cross-correlation of speckle patterns to determine the change in position over time. The use of objective (non-imaged) speckle offers a number of advantages over subjective (imaged) speckle, such as a reduction in the number of optical components, reduced modulation of speckles at the edges of the image, and improved light efficiency. The influence of the source/detector configuration on the speckle translation to vehicle translation scaling factor for objective speckle is investigated using a computer model and verified experimentally. Experimental measurements are presented at velocities up to 80  mm s(-1) which show accuracy better than 0.4%.

  10. Particle image velocimetry - Principles and first results

    International Nuclear Information System (INIS)

    Laporta, A.; Marechal, J.P.

    1997-01-01

    Particle Image Velocimetry (PIV) is a measurement technique elaborated towards the end of the 1970's, but which has developed considerably in recent years. The general principle of PIV is very simple and enables access to instantaneous velocity fields. It consists in recording images of tracer-particles injected into the flow and determining the distance covered by these particles. Since we know the time lapse between successive images of the same particle, we can derive the local fluid velocity. Among the many existing image acquisition and processing methods, the image inter-correlation analysis techniques, used with a pulsed laser source, is the most effective. Since we know the influence of different parameters (number of particles, beam power, time lapse between two successive images, size of query zones, etc.) on the quality of the final result, we can optimize practical adjustment of the PIV measurement scheme. The PIV was tested on the LAVITA hydraulic mockup (simulating the operation of a tangential fan). First results are, all in all, highly satisfactory. These have enabled the rapid drafting of instantaneous mean velocity field maps (20 images acquired in less than 90 seconds, with a post-processing time of about 10 minutes). Observation of the instantaneous fields has evidenced the presence of low frequency non-stationary phenomena which are not revealed by Laser Doppler Velocimetry (LDV). Quantitative comparison between LDV and PIV, concerning average fields, showed close results, with, however, local divergences which could be relatively marked. It must nevertheless be noted that the PIV measurements performed on LAVITA have not been optimized with a view to obtaining a consistently good accuracy level. Priority in the present case was given to the scope of the field explored, with a view to observing the large non-stationary structures within a flow. The PIV measurement technique is thus operational for prompt flow characterization. However

  11. Cruetzfieldt Jakob Disease e sindromi correlate Il centro di riferimento Piemontese e la sua sorveglianza epidemiologica

    Directory of Open Access Journals (Sweden)

    G. Catapano

    2003-05-01

    Full Text Available

    Le encefalopatie spongiformi trasmissibili (EST sono malattie del sistema nervoso dell’uomo, ad esito infausto. L’agente eziologico, la proteina prionica (PrP, può trasformarsi e accumularsi nella cellula nervosa causandone la morte. La scoperta negli anni ‘90 di una variante (v. Cruetzfieldt Jakob Disease, correlata all’encefalopatia spongiforme bovina, che colpisce soggetti sotto i 30 anni, ha aumentato l’interesse per le EST.

    I paesi della comunità europea hanno adottano misure di controllo della carne bovina e si sono dotati di osservatori epidemiologici. Pertanto anche in Italia si è avuta l’esigenza di doverne disporre. Si è deciso quindi di istituire anche in Piemonte un centro per la sorveglianza e la notifica delle EST tramite sorveglianza epidemiologica e diagnosi, per mezzo di indagini molecolari e neuropatologiche con la successiva costituzione di una banca dati condivisa con altri centri di riferimento regionali, per la raccolta di dati clinici e strumentali dai reparti di neurologia piemontesi con ricovero in sede dei casi di EST giunti all’osservazione.

    In sede vengono effettuati anche il prelievo, la raccolta, la conservazione di tessuti e altri materiali biologici e si svolgono successive indagini neurobiologiche quali:

     1 la ricerca della proteina 14 3 3 su liquor;

     2 determinazione genotipo del codone 129;

     3 determinazione della sequenza del gene della PrP,

     4 ricerca della PrP proteasi resistente a livello tissutale;

     5 determinazione del sottotipo di PrP. Le indagini neuropatologiche vengono effettuate in collaborazione con dipartimento di Neuroscienze dell’Università di Torino. Si intende inoltre fare promozione attiva delle attività e condivisione delle informazioni raccolte con altri centri.

  12. Helioseismology in a bottle: modal acoustic velocimetry

    International Nuclear Information System (INIS)

    Triana, Santiago Andrés; Zimmerman, Daniel S; Lathrop, Daniel P; Nataf, Henri-Claude; Thorette, Aurélien; Lekic, Vedran

    2014-01-01

    Measurement of the differential rotation of the Sun's interior is one of the great achievements of helioseismology, providing important constraints for stellar physics. The technique relies on observing and analyzing rotationally-induced splittings of p-modes in the star. Here, we demonstrate the first use of the technique in a laboratory setting. We apply it in a spherical cavity with a spinning central core (spherical-Couette flow) to determine the mean azimuthal velocity of the air filling the cavity. We excite a number of acoustic resonances (analogous to p-modes in the Sun) using a speaker and record the response with an array of small microphones on the outer sphere. Many observed acoustic modes show rotationally-induced splittings, which allow us to perform an inversion to determine the air's azimuthal velocity as a function of both radius and latitude. We validate the method by comparing the velocity field obtained through inversion against the velocity profile measured with a calibrated hot film anemometer. This modal acoustic velocimetry technique has great potential for laboratory setups involving rotating fluids in axisymmetric cavities. It will be useful especially in liquid metals where direct optical methods are unsuitable and ultrasonic techniques very challenging at best. (paper)

  13. FLEET Velocimetry Measurements on a Transonic Airfoil

    Science.gov (United States)

    Burns, Ross A.; Danehy, Paul M.

    2017-01-01

    Femtosecond laser electronic excitation tagging (FLEET) velocimetry was used to study the flowfield around a symmetric, transonic airfoil in the NASA Langley 0.3-m TCT facility. A nominal Mach number of 0.85 was investigated with a total pressure of 125 kPa and total temperature of 280 K. Two-components of velocity were measured along vertical profiles at different locations above, below, and aft of the airfoil at angles of attack of 0 deg, 3.5 deg, and 7deg. Measurements were assessed for their accuracy, precision, dynamic range, spatial resolution, and overall measurement uncertainty in the context of the applied flowfield. Measurement precisions as low as 1 m/s were observed, while overall uncertainties ranged from 4 to 5 percent. Velocity profiles within the wake showed sufficient accuracy, precision, and sensitivity to resolve both the mean and fluctuating velocities and general flow physics such as shear layer growth. Evidence of flow separation is found at high angles of attack.

  14. Stereo particle image velocimetry set up for measurements in the wake of scaled wind turbines

    Science.gov (United States)

    Campanardi, Gabriele; Grassi, Donato; Zanotti, Alex; Nanos, Emmanouil M.; Campagnolo, Filippo; Croce, Alessandro; Bottasso, Carlo L.

    2017-08-01

    Stereo particle image velocimetry measurements were carried out in the boundary layer test section of Politecnico di Milano large wind tunnel to survey the wake of a scaled wind turbine model designed and developed by Technische Universität München. The stereo PIV instrumentation was set up to survey the three velocity components on cross-flow planes at different longitudinal locations. The area of investigation covered the entire extent of the wind turbines wake that was scanned by the use of two separate traversing systems for both the laser and the cameras. Such instrumentation set up enabled to gain rapidly high quality results suitable to characterise the behaviour of the flow field in the wake of the scaled wind turbine. This would be very useful for the evaluation of the performance of wind farm control methodologies based on wake redirection and for the validation of CFD tools.

  15. Streamflow Observations From Cameras: Large-Scale Particle Image Velocimetry or Particle Tracking Velocimetry?

    Science.gov (United States)

    Tauro, F.; Piscopia, R.; Grimaldi, S.

    2017-12-01

    Image-based methodologies, such as large scale particle image velocimetry (LSPIV) and particle tracking velocimetry (PTV), have increased our ability to noninvasively conduct streamflow measurements by affording spatially distributed observations at high temporal resolution. However, progress in optical methodologies has not been paralleled by the implementation of image-based approaches in environmental monitoring practice. We attribute this fact to the sensitivity of LSPIV, by far the most frequently adopted algorithm, to visibility conditions and to the occurrence of visible surface features. In this work, we test both LSPIV and PTV on a data set of 12 videos captured in a natural stream wherein artificial floaters are homogeneously and continuously deployed. Further, we apply both algorithms to a video of a high flow event on the Tiber River, Rome, Italy. In our application, we propose a modified PTV approach that only takes into account realistic trajectories. Based on our findings, LSPIV largely underestimates surface velocities with respect to PTV in both favorable (12 videos in a natural stream) and adverse (high flow event in the Tiber River) conditions. On the other hand, PTV is in closer agreement than LSPIV with benchmark velocities in both experimental settings. In addition, the accuracy of PTV estimations can be directly related to the transit of physical objects in the field of view, thus providing tangible data for uncertainty evaluation.

  16. Stereo-particle image velocimetry uncertainty quantification

    International Nuclear Information System (INIS)

    Bhattacharya, Sayantan; Vlachos, Pavlos P; Charonko, John J

    2017-01-01

    Particle image velocimetry (PIV) measurements are subject to multiple elemental error sources and thus estimating overall measurement uncertainty is challenging. Recent advances have led to a posteriori uncertainty estimation methods for planar two-component PIV. However, no complete methodology exists for uncertainty quantification in stereo PIV. In the current work, a comprehensive framework is presented to quantify the uncertainty stemming from stereo registration error and combine it with the underlying planar velocity uncertainties. The disparity in particle locations of the dewarped images is used to estimate the positional uncertainty of the world coordinate system, which is then propagated to the uncertainty in the calibration mapping function coefficients. Next, the calibration uncertainty is combined with the planar uncertainty fields of the individual cameras through an uncertainty propagation equation and uncertainty estimates are obtained for all three velocity components. The methodology was tested with synthetic stereo PIV data for different light sheet thicknesses, with and without registration error, and also validated with an experimental vortex ring case from 2014 PIV challenge. Thorough sensitivity analysis was performed to assess the relative impact of the various parameters to the overall uncertainty. The results suggest that in absence of any disparity, the stereo PIV uncertainty prediction method is more sensitive to the planar uncertainty estimates than to the angle uncertainty, although the latter is not negligible for non-zero disparity. Overall the presented uncertainty quantification framework showed excellent agreement between the error and uncertainty RMS values for both the synthetic and the experimental data and demonstrated reliable uncertainty prediction coverage. This stereo PIV uncertainty quantification framework provides the first comprehensive treatment on the subject and potentially lays foundations applicable to volumetric

  17. Monitoraggio remoto delle deformazioni nell’isola di Santorini: una procedura integrata di analisi dati GPS presso la Sezione INGV di Bologna

    Directory of Open Access Journals (Sweden)

    Arianna Pesci

    2012-06-01

    Full Text Available Il GPS (Global Positioning System è un noto sistema di posizionamento globale in grado di fornire le coordinate spaziali di unoperatore, se munito di antenna e ricevitore satellitari, in qualunque punto della terra esso si trovi, in qualunque condizionemeteo ed in qualsiasi ora del giorno. Oggi al GPS, che è di proprietà del Dipartimento della Difesa degli Stati Uniti d'America(US DoD, si affiancano il GLONASS (sistema analogo russo e altri sistemi di posizionamento globale basati su tecniche interferometriche spaziali a partire da segnali a microonde, ad esempio i nascenti Galileo (europeo e BeiDou (cinese. Per questo motivo si parla diffusamente di sistemi GNSS cioè Global Navigation Satellite System.   Remote monitoring of deformations in the island of Santorini: an integrated procedure for GPS data analysis at the INGV in Bologna The GPS (Global Positioning System is a well-known global positioning  system  capable  of  providing  the  spatial  coordi-nates of an operator, if equipped with an antenna and a re-ceiver satellite, at any point on the earth , and in any weather conditions and at any time of the day. Today, the GPS, which is owned by the Department of Defense of the United States of America (U.S. DoD, is aided by the GLONASS (the Russian analogue system and other global positioning systems based on interferometry from space microwave signals, for example, the  nascent  Galileo  (European  and  Beidou  (China.  For  this reason we talk at today about GNSS Global Navigation Satel-lite System.

  18. DIAGNOSTICA PER IMMAGINI DI UN CAPOLAVORO DI CARAVAGGIO IMMAGINI OLTRE IL VISIBILE PER IL SEPPELLIMENTO DI SANTA LUCIA PROVENIENTE DALLA CHIESA DI SANTA LUCIA AL SEPOLCRO DI SIRACUSA

    Directory of Open Access Journals (Sweden)

    Fernanda Prestileo

    2012-04-01

    Full Text Available

    Il 28 maggio 1606 Michelangelo Merisi fugge da Roma dove non fará mai piú ritorno; l’ultimo duello gli è costato la condanna a morte. Iniziano per lui gli anni della latitanza, anni che trascorrerá tra Napoli, Malta e la Sicilia. Nel suo passaggio in Sicilia, Caravaggio realizza dipinti di eccezionale qualitá, sicuramente tra i piú belli della sua breve e intensa esistenza. Nell’isola l’artista arriva nell’ottobre del 1608, dopo l’ennesima fuga, questa volta da Malta. La sua prima tappa siciliana è Siracusa, dove vive un artista suo amico: Mario Minniti. Da lui trova riparo e lavoro perché dipinge su commissione una grande tela per la chiesa di Santa Lucia al Sepolcro, Il Seppellimento di Santa Lucia, realizzata in un breve lasso di tempo, trasferendosi Caravaggio a Messina nel dicembre dello stesso anno.

     

    Diagnostic campaign on Caravaggio’s painting

    The Assessorato dei Beni Culturali e dell’Identità Siciliana, Diparti-mento dei Beni Culturali e  dell'Identitá Siciliana, Regione Siciliana (i nomi italiani tutti in corsivo has carried out a diagnostic cam-paign on the painting Il Seppellimento di Santa Lucia (oil on canvas, 1608 by Michelangelo Merisi da Caravaggio, in order to evaluate the state of conservation of the work of art before its return to Syracu-se, in the Church of S. Lucia al Sepolcro (the original placing from which the painting was removed at the end of the Seventies due to the unsuitable and unstable environment conditions of the exhibi-tion area, which inevitably led to its bad conservation conditions. The diagnostic campaign has been carried out in situ with portable instruments, for a one-month period, during the open exhibition in the Regional Gallery of Sicily of Palazzo Abatellis in Palermo, where the painting has temporarily been displayed in 2006. The investigations were aimed at having a deeper knowledge of the work of art with reference

  19. L'Osservatorio delle disuguaglianze dell'Azienda USL di Ferrara

    Directory of Open Access Journals (Sweden)

    A. De Togni

    2003-05-01

    Full Text Available

    È ormai riconosciuto che bassa condizione socio-economica e limitato sviluppo culturale possono agire negativamente sul benessere individuale e sul livello di salute collettiva e determinano criticità nell’accesso alle cure, fenomeni che appaiono prevedibili, prevenibili e correggibili per migliorare la qualità e l’efficienza del sistema sanitario. Nell’area ferrarese sono presenti situazioni di svantaggio relativo non riconosciute e di difficile individuazione, il cui miglioramento si tradurrebbe in un beneficio sia per la condizione individuale che per la collettività.

    Obiettivi: la direzione sanitaria ed il Dipartimento di Sanità Pubblica dell’Azienda USL e l’Università degli Studi di Ferrara hanno dato vita al progetto “Osservatorio sulle disuguaglianze” allo scopo di sperimentare nuove modalità informative, più agili e tempestive delle rilevazioni censuarie, per individuare aree geografiche e/o fasce di popolazione verso le quali promuovere azioni di contrasto alle disuguaglianze in salute.

    Metodi: l’osservatorio prevede inizialmente tre sottoprogetti: 1. accesso agli screening femminili per definire i determinanti socio-ambientali e culturali delle donne non rispondenti; 2. salute neonati che, sulla base del nuovo certificato di assistenza al parto (CEDAP, mira a valutare situazioni di disuguaglianza in una fascia di età molto fragile; 3. coinvolgimento di medici di medicina generale (MMG, aderenti volontariamente all’indagine, nella raccolta sistematica di informazioni utili a monitorare il fenomeno delle disuguaglianze nella popolazione ferrarese. Risultati: l’attività dell’osservatorio è iniziata nell’aprile 2003 con l’elaborazione di un questionario da presentare alle donne non aderenti allo screening dei tumori del collo uterino e con la valutazione delle modalità di somministrazione del questionario (postale o telefonico avvalendosi della

  20. Flow Profile Study using miniature Laser-Doppler velocimetry

    NARCIS (Netherlands)

    Booij, W.E.; Booij, W.E.; de Jongh, A.; de Mul, F.F.M.

    1995-01-01

    We present a physics experiment, in which laser - Doppler velocimetry is used to make first - year university physics students realize that the idealized solutions offered by standard text books seldom are applicable without corrections, which often are numerical. This is demonstrated by carefully

  1. Broadband phase difference method for ultrasonic velocimetry in molten glass

    International Nuclear Information System (INIS)

    Kikura, Hiroshige; Ihara, Tomonori

    2016-01-01

    This study aims to develop ultrasonic Doppler velocimetry in molten glass. Realization of such a technique has two difficulties: ultrasonic transmission into molten salt and Doppler signal processing. Buffer rod technique was developed in our research to transmit ultrasound into high temperature molten glass. This article discusses newly developed signal processing technique named broadband phase difference method. (J.P.N.)

  2. Reusable holographic velocimetry system based on polarization multiplexing in Bacteriorhodopsin

    NARCIS (Netherlands)

    Koek, W.D.; Chan, V.S.S.; Ooms, T.A.; Bhattacharya, N.; Westerweel, J.; Braat, J.J.M.

    2005-01-01

    We present a novel holographic particle image velocimetry (HPIV) system using a reversible holographic material as the recording medium. In HPIV the three-dimensional flow field throughout a volume is detected by adding small tracer particles to a normally transparent medium. By recording the

  3. International Workshop on Detection, Classification and Localization of Marine Mammals Using Passive Acoustics (4th). International Workshop on Density Estimation of Marine Mammals Using Passive Acoustics (1st)

    Science.gov (United States)

    2009-09-13

    Università degli Studi di Pavia Dipartimento di Biologia Animale Centro Interdisciplinare di Bioacustica e Ricerche Ambientali 4th International...Dipartimento di Biologia Animale Centro Interdisciplinare di Bioacustica e Ricerche Ambientali 4th International Workshop on Detection, Classification...mail: gianni.pavan@unipv.it ORGANIZED BY: Università degli Studi di Pavia - Dipartimento di Biologia Animale CIBRA CENTRO INTERDISCIPLINARE DI

  4. Schlieren image velocimetry measurements in a rocket engine exhaust plume

    Science.gov (United States)

    Morales, Rudy; Peguero, Julio; Hargather, Michael

    2017-11-01

    Schlieren image velocimetry (SIV) measures velocity fields by tracking the motion of naturally-occurring turbulent flow features in a compressible flow. Here the technique is applied to measuring the exhaust velocity profile of a liquid rocket engine. The SIV measurements presented include discussion of visibility of structures, image pre-processing for structure visibility, and ability to process resulting images using commercial particle image velocimetry (PIV) codes. The small-scale liquid bipropellant rocket engine operates on nitrous oxide and ethanol as propellants. Predictions of the exhaust velocity are obtained through NASA CEA calculations and simple compressible flow relationships, which are compared against the measured SIV profiles. Analysis of shear layer turbulence along the exhaust plume edge is also presented.

  5. Laser speckle velocimetry applied to Rayleigh-Benard convection

    International Nuclear Information System (INIS)

    Arroyo, M.P.; Yonte, T.; Quintanilla, M.; Saviron, J.M.

    1986-01-01

    An application of speckle velocimetry technique to Rayleigh-Benard convection is presented. A 5-mW He-Ne laser allows precise determination of the two-dimensional velocity flow field, up to several mm/sec. The digital techniques used to analyze automatically the multiexposed photographs and to generate velocity and vorticity fields are described. The obtained results are in good agreement with previously reported data. The ability of the technique to cover other experimental conditions is discussed. 14 references

  6. Large scale particle image velocimetry with helium filled soap bubbles

    Energy Technology Data Exchange (ETDEWEB)

    Bosbach, Johannes; Kuehn, Matthias; Wagner, Claus [German Aerospace Center (DLR), Institute of Aerodynamics and Flow Technology, Goettingen (Germany)

    2009-03-15

    The application of particle image velocimetry (PIV) to measurement of flows on large scales is a challenging necessity especially for the investigation of convective air flows. Combining helium filled soap bubbles as tracer particles with high power quality switched solid state lasers as light sources allows conducting PIV on scales of the order of several square meters. The technique was applied to mixed convection in a full scale double aisle aircraft cabin mock-up for validation of computational fluid dynamics simulations. (orig.)

  7. Cross-correlation Doppler global velocimetry (CC-DGV)

    Science.gov (United States)

    Cadel, Daniel R.; Lowe, K. Todd

    2015-08-01

    A flow velocimetry method, cross-correlation Doppler global velocimetry (CC-DGV), is presented as a robust, simplified, and high dynamic range implementation of the Doppler global/planar Doppler velocimetry technique. A sweep of several gigahertz of the vapor absorption spectrum is used for each velocity sample, with signals acquired from both Doppler-shifted scattered light within the flow and a non-Doppler shifted reference beam. Cross-correlation of these signals yields the Doppler shift between them, averaged over the duration of the scan. With presently available equipment, velocities from 0 ms-1 to over 3000 ms-1 can notionally be measured simultaneously, making the technique ideal for high speed flows. The processing routine is shown to be robust against large changes in the vapor pressure of the iodine cell, benefiting performance of the system in facilities where ambient conditions cannot be easily regulated. Validation of the system was performed with measurements of a model wind turbine blade boundary layer made in a 1.83 m by 1.83 m subsonic wind tunnel for which laser Doppler velocimetry (LDV) measurements were acquired alongside the CC-DGV results. CC-DGV uncertainties of ±1.30 ms-1, ±0.64 ms-1, and ±1.11 ms-1 were determined for the orthogonal stream-wise, transverse-horizontal, and transverse-vertical velocity components, and root-mean-square deviations of 2.77 ms-1 and 1.34 ms-1 from the LDV validation results were observed for Reynolds numbers of 1.5 million and 2 million, respectively. Volumetric mean velocity measurements are also presented for a supersonic jet, with velocity uncertainties of ±4.48 ms-1, ±16.93 ms-1, and ±0.50 ms-1 for the orthogonal components, and self-validation done by collapsing the data with a physical scaling.

  8. Large scale particle image velocimetry with helium filled soap bubbles

    Science.gov (United States)

    Bosbach, Johannes; Kühn, Matthias; Wagner, Claus

    2009-03-01

    The application of Particle Image Velocimetry (PIV) to measurement of flows on large scales is a challenging necessity especially for the investigation of convective air flows. Combining helium filled soap bubbles as tracer particles with high power quality switched solid state lasers as light sources allows conducting PIV on scales of the order of several square meters. The technique was applied to mixed convection in a full scale double aisle aircraft cabin mock-up for validation of Computational Fluid Dynamics simulations.

  9. Particle Image Velocimetry Applications of Fluorescent Dye-Doped Particles

    OpenAIRE

    Petrosky, Brian Joseph

    2015-01-01

    Laser flare can often be a major issue in particle image velocimetry (PIV) involving solid boundaries in a flow or a gas-liquid interface. The use of fluorescent light from dye-doped particles has been demonstrated in water applications, but reproducing the technique in an airflow is more difficult due to particle size constraints and safety concerns. The following thesis is formatted in a hybrid manuscript style, including a full paper presenting the applications of fluorescent Kiton R...

  10. Particle Image Velocimetry Applications Using Fluorescent Dye-Doped Particles

    Science.gov (United States)

    Petrosky, Brian J.; Maisto, Pietro; Lowe, K. Todd; Andre, Matthieu A.; Bardet, Philippe M.; Tiemsin, Patsy I.; Wohl, Christopher J.; Danehy, Paul M.

    2015-01-01

    Polystyrene latex sphere particles are widely used to seed flows for velocimetry techniques such as Particle Image Velocimetry (PIV) and Laser Doppler Velocimetry (LDV). These particles may be doped with fluorescent dyes such that signals spectrally shifted from the incident laser wavelength may be detected via Laser Induced Fluorescence (LIF). An attractive application of the LIF signal is achieving velocimetry in the presence of strong interference from laser scatter, opening up new research possibilities very near solid surfaces or at liquid/gas interfaces. Additionally, LIF signals can be used to tag different fluid streams to study mixing. While fluorescence-based PIV has been performed by many researchers for particles dispersed in water flows, the current work is among the first in applying the technique to micron-scale particles dispersed in a gas. A key requirement for such an application is addressing potential health hazards from fluorescent dyes; successful doping of Kiton Red 620 (KR620) has enabled the use of this relatively safe dye for fluorescence PIV for the first time. In this paper, basic applications proving the concept of PIV using the LIF signal from KR620-doped particles are exhibited for a free jet and a twophase flow apparatus. Results indicate that while the fluorescence PIV techniques are roughly 2 orders of magnitude weaker than Mie scattering, they provide a viable method for obtaining data in flow regions previously inaccessible via standard PIV. These techniques have the potential to also complement Mie scattering signals, for example in multi-stream and/or multi-phase experiments.

  11. Iodine Tagging Velocimetry in a Mach 10 Wake

    Science.gov (United States)

    Balla, Robert Jeffrey

    2013-01-01

    A variation on molecular tagging velocimetry (MTV) [1] designated iodine tagging velocimetry (ITV) is demonstrated. Molecular iodine is tagged by two-photon absorption using an Argon Fluoride (ArF) excimer laser. A single camera measures fluid displacement using atomic iodine emission at 206 nm. Two examples ofMTVfor cold-flowmeasurements areN2OMTV [2] and Femtosecond Laser Electronic Excitation Tagging [3]. These, like most MTV methods, are designed for atmospheric pressure applications. Neither can be implemented at the low pressures (0.1- 1 Torr) in typical hypersonic wakes. Of all the single-laser/singlecamera MTV approaches, only Nitric-Oxide Planar Laser Induced Fluorescence-based MTV [4] has been successfully demonstrated in a Mach 10 wake. Oxygen quenching limits transit times to 500 ns and accuracy to typically 30%. The present note describes the photophysics of the ITV method. Off-body velocimetry along a line is demonstrated in the aerothermodynamically important and experimentally challenging region of a hypersonic low-pressure near-wake in a Mach 10 air wind tunnel. Transit times up to 10 µs are demonstrated with conservative errors of 10%.

  12. Verifica della qualitá delle indagini epidemiologiche per eventi epidemici di tossinfezione alimentare: l'esperienza del Servizio Igiene Pubblica della ASL RMG

    Directory of Open Access Journals (Sweden)

    A. Lancia

    2003-05-01

    Full Text Available

    Obiettivi: obiettivo dello studio è verificare il miglioramento della qualità delle indagini epidemiologiche per eventi epidemici di tossinfezione alimentare dopo l’implementazione di un protocollo aziendale condiviso tra i servizi del Dipartimento di Prevenzione della ASL RMG (SIP-SIAN-SV e l’attivazione della pronta disponibilità di una equipe dedicata.

    Metodi: sono state presi in considerazione tutti gli eventi epidemici di tossinfezione alimentare individuati dal SIP nel periodo 1998-2002: il periodo A (1998-1sem2000 è quello precedente all’attivazione del protocollo e il periodo B (2sem 2000-2002 è quello successivo. È stato realizzato un questionario per la raccolta retrospettiva dei dati archiviati; l’informatizzazione è stata effettuata con il programma EPIinfo vers. 6.0 e l’analisi con il software microsoft excel vers 7.0. Risultati: nel periodo A sono stati individuati n.14 eventi epidemici per un totale di 76 malati. Il servizio SIAN e/o SV è stato attivato nel 28% dei casi, il sopralluogo nel luogo di consumo del pasto è stato effettuato nel 42%(6/14 e nel 33% dei casi il campionamento dell’alimento ha individuato l’agente microbiologico. Nel periodo B invece sono stati individuati n.21 eventi epidemici per un totale di 202 malati. Il servizio SIAN e/o SV è stato attivato nel 71% dei casi, il sopralluogo nel luogo di consumo del pasto è stato effettuato nel 57%(12/21 e nel 57% dei casi il campionamento dell’alimento ha individuato l’agente microbiologico.

    Conclusioni: in seguito all’attivazione del protocollo è migliorata la qualità dei dati raccolti. L’istituzione di una equipe dedicata ha determinato una più accurata sorveglianza degli episodi di tossinfezione attraverso una maggiore efficienza nell’attivazione dei servizi SIAN-SV. Questa esperienza dimostra che l’integrazione tra i Servizi del Dipartimento di Prevenzione

  13. Lezioni di analisi matematica

    CERN Document Server

    Sbrana, Francesco

    1951-01-01

    Calcolo integrale delle funzioni di una variabile ; serie di funzioni di una variabile reale o complessa ; proprietà notevoli delle curve piane e sghembe ; ancora sulla intregazione delle funzioni di una variabile ; derivate e differenziali delle funzioni di più variabili ; integrali curvilinei, e di campo ; equazioni differenziali ordinarie ; cenni sulle equazioni alle derivate parziali ; cenni sulle serie di funzioni ortogonali.

  14. Design, Construction, Alignment, and Calibration of a Compact Velocimetry Experiment

    International Nuclear Information System (INIS)

    Morris I Kaufman; Robert M Malone; Brent C Frogget; David L Esquibel; Vincent T Romero; Gregory A Lare; Bart Briggs; Adam J Iverson; Daniel K Frayer; Douglas DeVore Brian Cata

    2007-01-01

    A velocimetry experiment has been designed to measure shock properties for small cylindrical metal targets (8-mm-diameter by 2-mm thick). A target is accelerated by high explosives, caught, and retrieved for later inspection. The target is expected to move at a velocity of 0.1 to 3 km/sec. The complete experiment canister is approximately 105 mm in diameter and 380 mm long. Optical velocimetry diagnostics include the Velocity Interferometer System for Any Reflector (VISAR) and Photon Doppler Velocimetry (PDV). The packaging of the velocity diagnostics is not allowed to interfere with the catchment or an X-ray imaging diagnostic. A single optical relay, using commercial lenses, collects Doppler-shifted light for both VISAR and PDV. The use of fiber optics allows measurement of point velocities on the target surface during accelerations occurring over 15 mm of travel. The VISAR operates at 532 nm and has separate illumination fibers requiring alignment. The PDV diagnostic operates at 1550 nm, but is aligned and focused at 670 nm. The VISAR and PDV diagnostics are complementary measurements and they image spots in close proximity on the target surface. Because the optical relay uses commercial glass, the axial positions of the optical fibers for PDV and VISAR are offset to compensate for chromatic aberrations. The optomechanical design requires careful attention to fiber management, mechanical assembly and disassembly, positioning of the foam catchment, and X-ray diagnostic field-of-view. Calibration and alignment data are archived at each stage of the assembly sequence

  15. Development of Hydroxyl Tagging Velocimetry for Low Velocity Flows

    Science.gov (United States)

    Andre, Matthieu A.; Bardet, Philippe M.; Burns, Ross A.; Danehy, Paul M.

    2016-01-01

    Hydroxyl tagging velocimetry (HTV) is a molecular tagging technique that relies on the photo-dissociation of water vapor into OH radicals and their subsequent tracking using laser induced fluorescence. Velocities are then obtained from time-of-flight calculations. At ambient temperature in air, the OH species lifetime is relatively short (<50 µs), making it suited for high speed flows. Lifetime and radicals formation increases with temperature, which allows HTV to also probe low-velocity, high-temperature flows or reacting flows such as flames. The present work aims at extending the domain of applicability of HTV, particularly towards low-speed (<10 m/s) and moderate (<500 K) temperature flows. Results are compared to particle image velocimetry (PIV) measurements recorded in identical conditions. Single shot and averaged velocity profiles are obtained in an air jet at room temperature. By modestly raising the temperature (100-200 degC) the OH production increases, resulting in an improvement of the signal-to-noise ratio (SNR). Use of nitrogen - a non-reactive gas with minimal collisional quenching - extends the OH species lifetime (to over 500 µs), which allows probing of slower flows or, alternately, increases the measurement precision at the expense of spatial resolution. Instantaneous velocity profiles are resolved in a 100degC nitrogen jet (maximum jet-center velocity of 6.5 m/s) with an uncertainty down to 0.10 m/s (1.5%) at 68% confidence level. MTV measurements are compared with particle image velocimetry and show agreement within 2%.

  16. Hybrid catadioptric system for advanced optical cavity velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Frayer, Daniel K.

    2018-02-06

    A probe including reflector is disclosed to measure the velocity distribution of a moving surface along many lines of sight. Laser light, directed to the surface by the probe and then reflected back from the surface, is Doppler shifted by the moving surface, collected into probe, and then directed to detection equipment through optic fibers. The received light is mixed with reference laser light and using photonic Doppler velocimetry, a continuous time record of the surface movement is obtained. An array of single-mode optical fibers provides an optic signal to one or more lens groups and a reflector, such as a parabolic reflector having a mirrored interior surface.

  17. Particle and speckle imaging velocimetry applied to a monostatic LIDAR

    Science.gov (United States)

    Halldorsson, Thorsteinn; Langmeier, Andreas; Prücklmeier, Andreas; Banakh, Viktor; Falits, Andrey

    2006-11-01

    A novel backscatter-lidar imaging method of visualization of air movement in the atmosphere is discussed in the paper. The method is based on the particle image velocimetry (PIV) principle, namely: pairs of image of laser illuminated thin atmospheric layers are recorded by CCD camera and then are cross correlated to obtain velocity information from these records. Both the way of computer simulation of atmospheric version of PIV technique and the first concept proof experiments are described in the paper. It is proposed that the method can find an application for visualization of wake vortices arising behind large aircrafts.

  18. Tomographic Particle Image Velocimetry Using Colored Shadow Imaging

    KAUST Repository

    Alarfaj, Meshal K.

    2016-02-01

    Tomographic Particle Image Velocimetry Using Colored Shadow Imaging by Meshal K Alarfaj, Master of Science King Abdullah University of Science & Technology, 2015 Tomographic Particle image velocimetry (PIV) is a recent PIV method capable of reconstructing the full 3D velocity field of complex flows, within a 3-D volume. For nearly the last decade, it has become the most powerful tool for study of turbulent velocity fields and promises great advancements in the study of fluid mechanics. Among the early published studies, a good number of researches have suggested enhancements and optimizations of different aspects of this technique to improve the effectiveness. One major aspect, which is the core of the present work, is related to reducing the cost of the Tomographic PIV setup. In this thesis, we attempt to reduce this cost by using an experimental setup exploiting 4 commercial digital still cameras in combination with low-cost Light emitting diodes (LEDs). We use two different colors to distinguish the two light pulses. By using colored shadows with red and green LEDs, we can identify the particle locations within the measurement volume, at the two different times, thereby allowing calculation of the velocities. The present work tests this technique on the flows patterns of a jet ejected from a tube in a water tank. Results from the images processing are presented and challenges discussed.

  19. Systematic Error of Acoustic Particle Image Velocimetry and Its Correction

    Directory of Open Access Journals (Sweden)

    Mickiewicz Witold

    2014-08-01

    Full Text Available Particle Image Velocimetry is getting more and more often the method of choice not only for visualization of turbulent mass flows in fluid mechanics, but also in linear and non-linear acoustics for non-intrusive visualization of acoustic particle velocity. Particle Image Velocimetry with low sampling rate (about 15Hz can be applied to visualize the acoustic field using the acquisition synchronized to the excitation signal. Such phase-locked PIV technique is described and used in experiments presented in the paper. The main goal of research was to propose a model of PIV systematic error due to non-zero time interval between acquisitions of two images of the examined sound field seeded with tracer particles, what affects the measurement of complex acoustic signals. Usefulness of the presented model is confirmed experimentally. The correction procedure, based on the proposed model, applied to measurement data increases the accuracy of acoustic particle velocity field visualization and creates new possibilities in observation of sound fields excited with multi-tonal or band-limited noise signals.

  20. Noise Studies of Externally Dispersed Interferometry for Doppler Velocimetry

    International Nuclear Information System (INIS)

    Erskine, D J; Edelstein, J; Lloyd, J; Muirhead, P

    2006-01-01

    Externally Dispersed Interferometry (EDI) is the series combination of a fixed-delay field-widened Michelson interferometer with a dispersive spectrograph. This combination boosts the spectrograph performance for both Doppler velocimetry and high resolution spectroscopy. The interferometer creates a periodic comb that multiplies against the input spectrum to create moire fringes, which are recorded in combination with the regular spectrum. Both regular and high-frequency spectral components can be recovered from the data--the moire component carries additional information that increases the signal to noise for velocimetry and spectroscopy. Here we present simulations and theoretical studies of the photon limited Doppler velocity noise in an EDI. We used a model spectrum of a 1600K temperature star. For several rotational blurring velocities 0, 7.5, 15 and 25 km/s we calculated the dimensionless Doppler quality index (Q) versus wavenumber v. This is the normalized RMS of the derivative of the spectrum and is proportional to the photon-limited Doppler signal to noise ratio

  1. The NASA Subsonic Jet Particle Image Velocimetry (PIV) Dataset

    Science.gov (United States)

    Bridges, James; Wernet, Mark P.

    2011-01-01

    Many tasks in fluids engineering require prediction of turbulence of jet flows. The present document documents the single-point statistics of velocity, mean and variance, of cold and hot jet flows. The jet velocities ranged from 0.5 to 1.4 times the ambient speed of sound, and temperatures ranged from unheated to static temperature ratio 2.7. Further, the report assesses the accuracies of the data, e.g., establish uncertainties for the data. This paper covers the following five tasks: (1) Document acquisition and processing procedures used to create the particle image velocimetry (PIV) datasets. (2) Compare PIV data with hotwire and laser Doppler velocimetry (LDV) data published in the open literature. (3) Compare different datasets acquired at the same flow conditions in multiple tests to establish uncertainties. (4) Create a consensus dataset for a range of hot jet flows, including uncertainty bands. (5) Analyze this consensus dataset for self-consistency and compare jet characteristics to those of the open literature. The final objective was fulfilled by using the potential core length and the spread rate of the half-velocity radius to collapse of the mean and turbulent velocity fields over the first 20 jet diameters.

  2. Analysis of particle kinematics in spheronization via particle image velocimetry.

    Science.gov (United States)

    Koester, Martin; Thommes, Markus

    2013-02-01

    Spheronization is a wide spread technique in pellet production for many pharmaceutical applications. Pellets produced by spheronization are characterized by a particularly spherical shape and narrow size distribution. The particle kinematic during spheronization is currently not well-understood. Therefore, particle image velocimetry (PIV) was implemented in the spheronization process to visualize the particle movement and to identify flow patterns, in order to explain the influence of various process parameters. The spheronization process of a common formulation was recorded with a high-speed camera, and the images were processed using particle image velocimetry software. A crosscorrelation approach was chosen to determine the particle velocity at the surface of the pellet bulk. Formulation and process parameters were varied systematically, and their influence on the particle velocity was investigated. The particle stream shows a torus-like shape with a twisted rope-like motion. It is remarkable that the overall particle velocity is approximately 10-fold lower than the tip speed of the friction plate. The velocity of the particle stream can be correlated to the water content of the pellets and the load of the spheronizer, while the rotation speed was not relevant. In conclusion, PIV was successfully applied to the spheronization process, and new insights into the particle velocity were obtained. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. L'espansione della criminalità organizzata nell'attività di impresa al Nord

    Directory of Open Access Journals (Sweden)

    Alberto Alessandri

    2016-12-01

    Full Text Available La presente ricerca, realizzata nell’ambito del Dipartimento di Studi Giuridici dell’Università Bocconi di Milano, si è proposta lo scopo di accertare empiricamente l’attività di contrasto all’infiltrazione mafiosa nelle attività economiche da parte della Procura e del Tribunale di Milano, nel periodo 2000 – 2015. Sono stati consultati, nella loro interezza, tutti i fascicoli dei procedimenti penali aperti (e accessibili nel periodo e per i quali vi sia stato un provvedimento di chiusura delle indagini preliminari. Poi è stata sono stati seguiti i processi fino in Cassazione. Sono stati inoltre considerati i fascicoli e i provvedimenti definitivi emessi dal Tribale di Prevenzione di Milano, riferiti allo stesso arco temporale, con attenzione centrata alle misure patrimoniali. Si è dato conto anche dei flussi dei procedimenti riguardanti aventi ad oggetto l’art. 416-bis c.p., oltre che del Tribunale di Milano, di quelli di Roma, Napoli, Reggio Calabria, Palermo. I dati ricavati dai fascicoli sono stati elaborati con un apposito software, per ottenere le correlazioni e le statistiche ritenute di maggior interesse, in specie riguardo alla penetrazione nel settore economico e imprenditoriale. Parole chiave: mafia; criminalità organizzata; ‘ndrangheta; attività economiche; Italia settentrionale.   This research, conducted within the Department of Law of Bocconi University in Milan, aims to empirically ascertain the actions implemented by the Office of the Public Prosecution and the Court of Milan to counteract the Mafia’s infiltration in economic activities in the period from 2000 to 2015. All the records pertaining to criminal proceedings opened (and accessible in the relevant period - and in relation to which preliminary investigations were closed - were consulted in their entirety. The proceedings were then followed up until the Court of Cassation. In addition, all the records and final decisions issued by the Tribunale di

  4. Control and Estimation of Distributed Parameter Systems. Volume 126, International Conference in Vorau (Austria)

    Science.gov (United States)

    1998-01-01

    Parabolic Boundary Control Problem ARIELA BRIANI AND MAURIZIO FALCONE Dipartimento di Matematica Universitä di Pisa Dipartimento di Matematica ...Ministry for University and Scientific Research (MURST Project "Analisi Numerica e Matematica Computazionale"). 50 A Priori Estimates for the...Briani Dipartimento di Matematica Universitä di Pisa Via Buonarroti 2 1-56126 Pisa e-mail:briani@dm.unipi.it Maurizio Falcone Dipartimento di

  5. Three-dimensional particle image velocimetry measurement technique

    International Nuclear Information System (INIS)

    Hassan, Y.A.; Seeley, C.H.; Henderson, J.A.; Schmidl, W.D.

    2004-01-01

    The experimental flow visualization tool, Particle Image Velocimetry (PIV), is being used to determine the velocity field in two-dimensional fluid flows. In the past few years, the technique has been improved to allow the capture of flow fields in three dimensions. This paper describes changes which were made to two existing two-dimensional tracking algorithms to enable them to track three-dimensional PIV data. Results of the tests performed on these three-dimensional routines with synthetic data are presented. Experimental data was also used to test the tracking algorithms. The test setup which was used to acquire the three-dimensional experimental data is described, along with the results from both of the tracking routines which were used to analyze the experimental data. (author)

  6. Multiparticle imaging velocimetry measurements in two-phase flow

    International Nuclear Information System (INIS)

    Hassan, Y.A.

    1998-01-01

    The experimental flow visualization tool, Particle Image Velocimetry (PIV), is being extended to determine the velocity fields in two and three-dimensional, two-phase fluid flows. In the past few years, the technique has attracted quite a lot of interest. PIV enables fluid velocities across a region of a flow to be measured at a single instant in time in global domain. This instantaneous velocity profile of a given flow field is determined by digitally recording particle (microspheres or bubbles) images within the flow over multiple successive video frames and then conducting flow pattern identification and analysis of the data. This paper presents instantaneous velocity measurements in various two and three- dimensional, two-phase flow situations. (author)

  7. Real-time particle image velocimetry based on FPGA technology

    International Nuclear Information System (INIS)

    Iriarte Munoz, Jose Miguel

    2008-01-01

    Particle image velocimetry (PIV), based on laser sheet, is a method for image processing and calculation of distributed velocity fields.It is well established as a fluid dynamics measurement tool, being applied to liquid, gases and multiphase flows.Images of particles are processed by means of computationally demanding algorithms, what makes its real-time implementation difficult.The most probable displacements are found applying two dimensional cross-correlation function. In this work, we detail how it is possible to achieve real-time visualization of PIV method by designing an adaptive embedded architecture based on FPGA technology.We show first results of a physical field of velocity calculated by this platform system in a real-time approach. [es

  8. Particle image velocimetry new developments and recent applications

    CERN Document Server

    Willert, Christian E

    2008-01-01

    Particle Image Velocimetry (PIV) is a non-intrusive optical measurement technique which allows capturing several thousand velocity vectors within large flow fields instantaneously. Today, the PIV technique has spread widely and differentiated into many distinct applications, from micro flows over combustion to supersonic flows for both industrial needs and research. Over the past decade the measurement technique and the hard- and software have been improved continuously so that PIV has become a reliable and accurate method for "real life" investigations. Nevertheless there is still an ongoing process of improvements and extensions of the PIV technique towards 3D, time resolution, higher accuracy, measurements under harsh conditions and micro- and macroscales. This book gives a synopsis of the main results achieved during the EC-funded network PivNet 2 as well as a survey of the state-of-the-art of scientific research using PIV techniques in different fields of application.

  9. Digital Particle Image Velocimetry: Partial Image Error (PIE)

    International Nuclear Information System (INIS)

    Anandarajah, K; Hargrave, G K; Halliwell, N A

    2006-01-01

    This paper quantifies the errors due to partial imaging of seeding particles which occur at the edges of interrogation regions in Digital Particle Image Velocimetry (DPIV). Hitherto, in the scientific literature the effect of these partial images has been assumed to be negligible. The results show that the error is significant even at a commonly used interrogation region size of 32 x 32 pixels. If correlation of interrogation region sizes of 16 x 16 pixels and smaller is attempted, the error which occurs can preclude meaningful results being obtained. In order to reduce the error normalisation of the correlation peak values is necessary. The paper introduces Normalisation by Signal Strength (NSS) as the preferred means of normalisation for optimum accuracy. In addition, it is shown that NSS increases the dynamic range of DPIV

  10. Multipoint photonic doppler velocimetry using optical lens elements

    Science.gov (United States)

    Frogget, Brent Copely; Romero, Vincent Todd

    2014-04-29

    A probe including a fisheye lens is disclosed to measure the velocity distribution of a moving surface along many lines of sight. Laser light, directed to the surface and then reflected back from the surface, is Doppler shifted by the moving surface, collected into fisheye lens, and then directed to detection equipment through optic fibers. The received light is mixed with reference laser light and using photonic Doppler velocimetry, a continuous time record of the surface movement is obtained. An array of single-mode optical fibers provides an optic signal to an index-matching lens and eventually to a fisheye lens. The fiber array flat polished and coupled to the index-matching lens using index-matching gel. Numerous fibers in a fiber array project numerous rays through the fisheye lens which in turn project many measurement points at numerous different locations to establish surface coverage over a hemispherical shape with very little crosstalk.

  11. New adaptive sampling method in particle image velocimetry

    International Nuclear Information System (INIS)

    Yu, Kaikai; Xu, Jinglei; Tang, Lan; Mo, Jianwei

    2015-01-01

    This study proposes a new adaptive method to enable the number of interrogation windows and their positions in a particle image velocimetry (PIV) image interrogation algorithm to become self-adapted according to the seeding density. The proposed method can relax the constraint of uniform sampling rate and uniform window size commonly adopted in the traditional PIV algorithm. In addition, the positions of the sampling points are redistributed on the basis of the spring force generated by the sampling points. The advantages include control of the number of interrogation windows according to the local seeding density and smoother distribution of sampling points. The reliability of the adaptive sampling method is illustrated by processing synthetic and experimental images. The synthetic example attests to the advantages of the sampling method. Compared with that of the uniform interrogation technique in the experimental application, the spatial resolution is locally enhanced when using the proposed sampling method. (technical design note)

  12. Characterization of extrusion flow using particle image velocimetry

    Directory of Open Access Journals (Sweden)

    2009-09-01

    Full Text Available The aim of this study was the characterization of polymer flows within an extrusion die using particle image velocimetry (PIV in very constraining conditions (high temperature, pressure and velocity. Measurements were realized on semi-industrial equipments in order to have test conditions close to the industrial ones. Simple flows as well as disrupted ones were studied in order to determine the capabilities and the limits of the method. The analysis of the velocity profiles pointed out significant wall slip, which was confirmed by rheological measurements based on Mooney's method. Numerical simulations were used to connect the two sets of measurements and to simulate complex velocity profiles for comparison to the experimental ones. A good agreement was found between simulations and experiments providing wall slip is taken into account in the simulation.

  13. Holographic Particle Image Velocimetry and its Application in Engine Development

    International Nuclear Information System (INIS)

    Coupland, J M; Garner, C P; Alcock, R D; Halliwell, N A

    2006-01-01

    This paper reviews Holographic Particle Image Velocimetry (HPIV) as a means to make three-component velocity measurements throughout a three-dimensional flow-field of interest. A simplified treatment of three-dimensional scalar wave propagation is outlined and subsequently used to illustrate the principles of complex correlation analysis. It is shown that this type of analysis provides the three-dimensional correlation of the propagating, monochromatic fields recorded by the hologram. A similar approach is used to analyse the Object Conjugate Reconstruction (OCR) technique to resolve directional ambiguity by introducing an artificial image shift to the reconstructed particle images. An example of how these methods are used together to measure the instantaneous flow fields within a motored Diesel engine is then described

  14. Lezioni di fisica teorica

    CERN Document Server

    Caldirola, Piero

    Richiami di meccanica analitica ; richiami di termodinamica ; richiami di elettromagnetismo ; appunti sulla teoria della relatività ; la non validità delle teorie classiche nel mondo microscopico ; la meccanica atomica di Bohr e Sommerfeld ; I fondamenti della meccanica quantistica ; applicazioni nell'equazione di Schroedinger ; meccanica quantistica dei sistemi l'atomo di idrogeno ; particella in un campo elettrico e magnetico ; il calcolo delle perturbazioni nella teoria quantistica ; teoria dell'emissione e dell'assorbimento della luce ; sistemi di particelle identiche ; il legame chimico omopolare nella molecola di idrogeno ; la teoria di Dirac.

  15. Full-field particle velocimetry with a photorefractive optical novelty filter

    International Nuclear Information System (INIS)

    Woerdemann, Mike; Holtmann, Frank; Denz, Cornelia

    2008-01-01

    We utilize the finite time constant of a photorefractive optical novelty filter microscope to access full-field velocity information of fluid flows on microscopic scales. In contrast to conventional methods such as particle image velocimetry and particle tracking velocimetry, not only image acquisition of the tracer particle field but also evaluation of tracer particle velocities is done all-optically by the novelty filter. We investigate the velocity dependent parameters of two-beam coupling based optical novelty filters and demonstrate calibration and application of a photorefractive velocimetry system. Theoretical and practical limits to the range of accessible velocities are discussed

  16. Storie di genere, storie di partito

    Directory of Open Access Journals (Sweden)

    Elisa Bellè

    2012-04-01

    Full Text Available Lo studio delle narrazioni di genere all'interno di questo tipo di organizzazione desta inoltre un particolare interesse anche in ragione della sottorappresentazione delle donne nella sfera della politica. Si tratta di un deficit democratico che coinvolge i sistemi politici moderni nel loro complesso, ma che interessa l'Italia con una particolare gravità ed evidenza. La questione della sottorappresentazione politica delle donne è stata sinora affrontata prevalentemente in termini tecnico-legali (politiche di pari opportunità ed azione positiva, o di teoria politica (la dicotomia pubblico-maschile e privato-femminile come fondamento del contratto sessuale della politica. Mancano invece contributi che guardino ai partiti come organizzazioni largamente responsabili dei processi di selezione e promozione delle carriere politiche, dunque come luoghi di quotidiana produzione di pratiche e culture di genere, più o meno egualitarie o, viceversa, discriminatorie. Sulla base di tale vuoto di ricerca e riflessione, il presente articolo si propone di mettere in luce le pratiche e le culture di genere che emergono dai racconti di uomini e donne all'interno di due organizzazioni partitiche, una di destra e una di sinistra, situate nel contesto territoriale della provincia di Trento. La ricerca è stata condotta attraverso lo strumento dell'intervista semi-strutturata, coinvolgendo quattro donne e quattro uomini, divisi per coppie di età (un uomo ed una donna giovani ed un uomo ed una donna da lungo presenti nel partito, accostabili per quanto concerne ruolo e posizione nelle organizzazioni partitiche considerate. L'attenzione analitica si è concentrata sulla costruzione del genere di uomini e donne intervistati/e, intesa sia come dimensione ed esperienza individuale (le storie di genere dei/lle singoli/e, sia come dimensione organizzativa più ampia (le storie di genere delle organizzazioni, narrate dalle diverse voci. Un'ulteriore dimensione analitica

  17. Development and assessment of transparent soil and particle image velocimetry in dynamic soil-structure interaction

    Science.gov (United States)

    2007-02-01

    This research combines Particle Image Velocimetry (PIV) and transparent soil to investigate the dynamic rigid block and soil interaction. In order to get a low viscosity pore fluid for the transparent soil, 12 different types of chemical solvents wer...

  18. 3D Flow Field Measurements using Aerosol Correlation Velocimetry, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — AeroMancer Technologies proposes to develop a 3D Global Lidar Airspeed Sensor (3D-LGAS) using Aerosol Correlation Velocimetry for standoff sensing of high-resolution...

  19. Demonstration of Clean Particle Seeding for Particle Image Velocimetry in a Closed Circuit Supersonic Wind Tunnel

    National Research Council Canada - National Science Library

    McNiel, Charles M

    2007-01-01

    The purpose of this research was to determine whether solid carbon dioxide (CO2) particles might provide a satisfactory, and cleaner, alternative to traditional seed material for Particle Image Velocimetry (PIV...

  20. Fondamenti di fisica dei plasmi

    CERN Document Server

    Golant, V E; Sacharov, I E

    1983-01-01

    Introduzione ; collisioni del plasma ; equazioni cinetiche per particelle cariche ; plasmi in equilibrio termodinamico ; funzione di distribuzione di particelle cariche in un campo elettrico ; equazioni dei momenti della funzione di distribuzione ; processi di trasporto nel plasma in assenza di campi magnetici ; moto di particelle cariche nel plasma in presenza di campi magnetici ; processi di trasporto in campo magnetico ; confinamento del plasma mediante campi magnetici.

  1. Proposta di utilizzo di metodologie termografiche per il controllo di qualità di componenti meccanici

    Directory of Open Access Journals (Sweden)

    Roberto D’Andrea

    2010-04-01

    Full Text Available In base all’esperienza maturata in anni di sperimentazione sull’analisi delle caratteristiche meccaniche dei materiali mediante indagine termografica, nel presente lavoro è proposta una procedura per il controllo di qualità di componenti meccanici in linea di produzione, che è già stata argomento di brevetto. Lo sviluppo di questo lavoro si colloca nell’ambito del progetto FIRB Smart Reflex “Sistemi di produzione intelligenti, flessibili e riconfigurabili”. L’attività svolta dal DIIM riguarda il controllo avanzato dell’affidabilità di componenti meccanici per l’industria automobilistica. Viene proposta, quindi, la realizzazione di una cella di controllo in linea di produzione capace di valutare la presenza di eventuali componenti difettosi attraverso l’analisi termica degli stessi, sollecitati secondo un modello predefinito. L’attività, svolta in questa prima fase in laboratorio, è facilmente trasferibile in linea di produzione, considerando la possibilità di realizzare celle di prova in ambiente controllato, con condizioni praticamente identiche a quelle di laboratorio, eliminando gli effetti di disturbo che possono influenzare la risposta dell’indagine termografica in ambiente non strutturato.

  2. Una ricerca sulla qualità della vita scolastica di bambini e bambine affetti da malattie emorragiche congenite. Lettura critica dei dati e considerazioni pedagogiche.

    Directory of Open Access Journals (Sweden)

    Alessandra Gigli

    2009-07-01

    Full Text Available Il presente rapporto di ricerca costituisce l'esito del lavoro svolto dalle ricercatrici A. Gigli, S. Demozzi del Dipartimento di Scienze dell’Educazione dell’Università di Bologna all'interno del progetto Strategico di Ateneo dal titolo “Definizione di linee guida d’intervento sui pazienti pediatrici affetti da malattie emorragiche congenite: aspetti medici, psicosociali, educativi ed etici”. L'obiettivo principale del lavoro è stato quello di analizzare il punto di vista degli insegnanti in merito alla vita scolastica dei bambini con malattie emorragiche congenite (Mec, le loro relazioni con insegnanti e compagni, i rapporti tra scuola e famiglie. Per monitorare questi aspetti legati alla vita scolastica, nel 2008 è stata realizzata un’indagine sul campo che ha coinvolto insegnanti di scuole dell’infanzia, scuole primarie, scuole secondarie di primo grado della Provincia di Bologna che hanno in classe un/a bambino/a affetti da Mec. Le rilevazioni effettuate tramite interviste semi strutturate hanno avuto i seguenti obiettivi: verificare l’esistenza di rappresentazioni “distorte” delle patologie ed eventuali pregiudizi esistenti; analizzare il processo informativo attraverso cui i docenti conoscono la situazione del bambino e vengono informati sulle Mec; rilevare i nodi problematici e punti di forza, che qualificano negativamente o positivamente le relazione scuola-famiglia; monitorare l’esistenza di pregiudizi in merito alle capacità cognitive dei bambini; verificare se, secondo i docenti, la malattia influisce sulla qualità della relazione educativa, indagando, in particolare, sugli aspetti comunicativi; rilevare eventuali problematiche di integrazione nel gruppo dei pari; verificare se l’adozione di strategie per permettere una migliore integrazione o lo svolgimento delle attività didattiche, ludiche e sportive; rilevare i bisogni formativi e informativi dei docenti. Nell’articolo si presenta una lettura

  3. Analysis of bubbly flow using particle image velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Todd, D.R.; Ortiz-Villafuerte, J.; Schmidl, W.D.; Hassan, Y.A. [Texas A and M University, Nuclear Engineering Dept., College Stagion, TX (United States); Sanchez-Silva, F. [ESIME, INP (Mexico)

    2001-07-01

    The local phasic velocities can be determined in two-phase flows if the phases can be separated during analysis. The continuous liquid velocity field can be captured using standard Particle Image Velocimetry (PIV) techniques in two-phase flows. PIV is now a well-established, standard flow measurement technique, which provides instantaneous velocity fields in a two-dimensional plane of finite thickness. PIV can be extended to three dimensions within the plane with special considerations. A three-dimensional shadow PIV (SPIV) measurement apparatus can be used to capture the dispersed phase flow parameters such as velocity and interfacial area. The SPIV images contain only the bubble images, and can be easily analyzed and the results used to separate the dispersed phase from the continuous phase in PIV data. An experimental system that combines the traditional PIV technique with SPIV will be described and sample data will be analyzed to demonstrate an advanced turbulence measurement method in a two-phase bubbly flow system. Also, a qualitative error analysis method that allows users to reduce the number of erroneous vectors obtained from the PIV measurements will be discussed. (authors)

  4. Particle Image Velocimetry (PIV) Measurements of Suspension-Feeding Velocities

    Science.gov (United States)

    Du Clos, K.; Jones, I. T.; Carrier, T. J.; Jumars, P. A.

    2016-02-01

    Active suspension feeders, such as bivalves and tunicates, connect benthic and pelagic ecosystems by packaging suspended matter into larger fecal and pseudofecal particles, greatly enhancing the flux of carbon and nutrients from the water column to the benthos. The volume of water processed by a population of suspension feeders is commonly estimated by scaling up results from experiments that measure the clearance rate (the volume of water cleared of particles per time) of one or a few individual suspension feeders. Clearance rates vary, however, between species, within a species, and over time for a single individual; and the velocity fields produced by suspension feeders are likely to interact in complex ways. We measured the water velocity fields produced by two species of bivalve, Mya arenaria and Mercenaria mercenaria, and the tunicate Ciona intestinalis, using particle image velocimetry (PIV). We used these measurements to calculate flow rates and Reynolds numbers of inhalant and exhalant siphons. We also observed strong entrainment of water by M. arenaria's exhalant siphon jet that may help to explain how the clam avoids depleting the water around it of particles and oxygen as it feeds. We are using these measurements to inform computational fluid mechanics (CFD) models of suspension feeding, allowing us to examine the interactions of flow fields produced by multiple suspension feeders and other effects not quantified by clearance-rate measurements.

  5. Hydroxyl tagging velocimetry in a supersonic flow over a cavity

    International Nuclear Information System (INIS)

    Pitz, Robert W.; Lahr, Michael D.; Douglas, Zachary W.; Wehrmeyer, Joseph A.; Hu Shengteng; Carter, Campbell D.; Hsu, Kuang-Yu; Lum, Chee; Koochesfahani, Manoochehr M.

    2005-01-01

    Hydroxyl tagging velocimetry (HTV) measurements of velocity were made in a Mach 2 (M 2) flow with a wall cavity. In the HTV method, ArF excimer laser (193 nm) beams pass through a humid gas and dissociate H2O into H + OH to form a tagging grid of OH molecules. In this study, a 7x7 grid of hydroxyl (OH) molecules is tracked by planar laser-induced fluorescence. The grid motion over a fixed time delay yields about 50 velocity vectors of the two-dimensional flow in the plane of the laser sheets. Velocity precision is limited by the error in finding the crossing location of the OH lines written by the excimer tag laser. With a signal-to-noise ratio of about 10 for the OH lines, the determination of the crossing location is expected to be accurate within ±0.1 pixels. Velocity precision within the freestream, where the turbulence is low, is consistent with this error. Instantaneous, single-shot measurements of two-dimensional flow patterns were made in the nonreacting M 2 flow with a wall cavity under low- and high-pressure conditions. The single-shot profiles were analyzed to yield mean and rms velocity profiles in the M 2 nonreacting flow

  6. Evaluation of magnetic resonance velocimetry for steady flow.

    Science.gov (United States)

    Ku, D N; Biancheri, C L; Pettigrew, R I; Peifer, J W; Markou, C P; Engels, H

    1990-11-01

    Whole body magnetic resonance (MR) imaging has recently become an important diagnostic tool for cardiovascular diseases. The technique of magnetic resonance phase velocity encoding allows the quantitative measurement of velocity for an arbitrary component direction. A study was initiated to determine the ability and accuracy of MR velocimetry to measure a wide range of flow conditions including flow separation, three-dimensional secondary flow, high velocity gradients, and turbulence. A steady flow system pumped water doped with manganese chloride through a variety of test sections. Images were produced using gradient echo sequences on test sections including a straight tube, a curved tube, a smoothly converging-diverging nozzle, and an orifice. Magnetic resonance measurements of laminar and turbulent flows were depicted as cross-sectional velocity profiles. MR velocity measurements revealed such flow behavior as spatially varying velocity, recirculation and secondary flows over a wide range of conditions. Comparisons made with published experimental laser Doppler anemometry measurements and theoretical calculations for similar flow conditions revealed excellent accuracy and precision levels. The successful measurement of velocity profiles for a variety of flow conditions and geometries indicate that magnetic resonance imaging is an accurate, non-contacting velocimeter.

  7. Application of adaptive Kalman filter in vehicle laser Doppler velocimetry

    Science.gov (United States)

    Fan, Zhe; Sun, Qiao; Du, Lei; Bai, Jie; Liu, Jingyun

    2018-03-01

    Due to the variation of road conditions and motor characteristics of vehicle, great root-mean-square (rms) error and outliers would be caused. Application of Kalman filter in laser Doppler velocimetry(LDV) is important to improve the velocity measurement accuracy. In this paper, the state-space model is built by using current statistical model. A strategy containing two steps is adopted to make the filter adaptive and robust. First, the acceleration variance is adaptively adjusted by using the difference of predictive observation and measured observation. Second, the outliers would be identified and the measured noise variance would be adjusted according to the orthogonal property of innovation to reduce the impaction of outliers. The laboratory rotating table experiments show that adaptive Kalman filter greatly reduces the rms error from 0.59 cm/s to 0.22 cm/s and has eliminated all the outliers. Road experiments compared with a microwave radar show that the rms error of LDV is 0.0218 m/s, and it proves that the adaptive Kalman filtering is suitable for vehicle speed signal processing.

  8. Analysis of bubbly flow using particle image velocimetry

    International Nuclear Information System (INIS)

    Todd, D.R.; Ortiz-Villafuerte, J.; Schmidl, W.D.; Hassan, Y.A.; Sanchez-Silva, F.

    2001-01-01

    The local phasic velocities can be determined in two-phase flows if the phases can be separated during analysis. The continuous liquid velocity field can be captured using standard Particle Image Velocimetry (PIV) techniques in two-phase flows. PIV is now a well-established, standard flow measurement technique, which provides instantaneous velocity fields in a two-dimensional plane of finite thickness. PIV can be extended to three dimensions within the plane with special considerations. A three-dimensional shadow PIV (SPIV) measurement apparatus can be used to capture the dispersed phase flow parameters such as velocity and interfacial area. The SPIV images contain only the bubble images, and can be easily analyzed and the results used to separate the dispersed phase from the continuous phase in PIV data. An experimental system that combines the traditional PIV technique with SPIV will be described and sample data will be analyzed to demonstrate an advanced turbulence measurement method in a two-phase bubbly flow system. Also, a qualitative error analysis method that allows users to reduce the number of erroneous vectors obtained from the PIV measurements will be discussed. (authors)

  9. Particle image velocimetry investigation of a finite amplitude pressure wave

    Science.gov (United States)

    Thornhill, D.; Currie, T.; Fleck, R.; Chatfield, G.

    2006-03-01

    Particle image velocimetry is used to study the motion of gas within a duct subject to the passage of a finite amplitude pressure wave. The wave is representative of the pressure waves found in the exhaust systems of internal combustion engines. Gas particles are accelerated from stationary to 150 m/s and then back to stationary in 8 ms. It is demonstrated that gas particles at the head of the wave travel at the same velocity across the duct cross section at a given point in time. Towards the tail of the wave viscous effects are plainly evident causing the flow profile to tend towards parabolic. However, the instantaneous mean particle velocity across the section is shown to match well with the velocity calculated from a corresponding measured pressure history using 1D gas dynamic theory. The measured pressure history at a point in the duct was acquired using a high speed pressure transducer of the type typically used for engine research in intake and exhaust systems. It is demonstrated that these are unable to follow the rapid changes in pressure accurately and that they are prone to resonate under certain circumstances.

  10. Microparticle tracking velocimetry as a tool for microfluidic flow measurements

    Science.gov (United States)

    Salipante, Paul; Hudson, Steven D.; Schmidt, James W.; Wright, John D.

    2017-07-01

    The accurate measurement of flows in microfluidic channels is important for commercial and research applications. We compare the accuracy of flow measurement techniques over a wide range flows. Flow measurements made using holographic microparticle tracking velocimetry (µPTV) and a gravimetric flow standard over the range of 0.5-100 nL/s agree within 0.25%, well within the uncertainty of the two flow systems. Two commercial thermal flow sensors were used as the intermediaries (transfer standards) between the two flow measurement systems. The gravimetric flow standard was used to calibrate the thermal flow sensors by measuring the rate of change of the mass of liquid in a beaker on a micro-balance as it fills. The holographic µPTV flow measurements were made in a rectangular channel and the flow was seeded with 1 µm diameter polystyrene spheres. The volumetric flow was calculated using the Hagen-Pouiseille solution for a rectangular channel. The uncertainty of both flow measurement systems is given. For the gravimetric standard, relative uncertainty increased for decreasing flows due to surface tension forces between the pipette carrying the flow and the free surface of the liquid in the beaker. The uncertainty of the holographic µPTV measurements did not vary significantly over the measured flow range, and thus comparatively are especially useful at low flow velocities.

  11. Channel flow structure measurements using particle image velocimetry

    International Nuclear Information System (INIS)

    Norazizi Mohamed; Noraeini Mokhtar; Aziz Ibrahim; Ramli Abu Hassan

    1996-01-01

    Two different flow structures in a laboratory channel were examined using a flow visualization technique, known as Particle Image Velocimetry (PIV). The first channel flow structure was that of a steady flow over a horizontal channel bottom. Photographs of particle displacements were taken in the boundary layer in a plane parallel to the flow. These photographs were analyzed to give simultaneous measurements of two components of the velocity at hundreds of points in the plane. Averaging these photographs gave the velocity profile a few millimeters from the bottom of the channel to the water surface. The results gave good agreement with the known boundary layer theory. This technique is extended to the study of the structure under a progressive wave in the channel. A wavelength of the propagating wave is divided into sections by photographing it continously for a number of frames. Each frame is analyzed and a velocity field under this wave at various phase points were produced with their respective directions. The results show that velocity vectors in a plane under the wave could be achieved instantaneously and in good agreement with the small amplitude wave theory

  12. Zebrafish swimming in the flow: a particle image velocimetry study

    Directory of Open Access Journals (Sweden)

    Violet Mwaffo

    2017-11-01

    Full Text Available Zebrafish is emerging as a species of choice for the study of a number of biomechanics problems, including balance development, schooling, and neuromuscular transmission. The precise quantification of the flow physics around swimming zebrafish is critical toward a mechanistic understanding of the complex swimming style of this fresh-water species. Although previous studies have elucidated the vortical structures in the wake of zebrafish swimming in placid water, the flow physics of zebrafish swimming against a water current remains unexplored. In an effort to illuminate zebrafish swimming in a dynamic environment reminiscent of its natural habitat, we experimentally investigated the locomotion and hydrodynamics of a single zebrafish swimming in a miniature water tunnel using particle image velocimetry. Our results on zebrafish locomotion detail the role of flow speed on tail beat undulations, heading direction, and swimming speed. Our findings on zebrafish hydrodynamics offer a precise quantification of vortex shedding during zebrafish swimming and demonstrate that locomotory patterns play a central role on the flow physics. This knowledge may help clarify the evolutionary advantage of burst and cruise swimming movements in zebrafish.

  13. Il rifornimento della rete commerciale al dettaglio della Provincia di Napoli

    Directory of Open Access Journals (Sweden)

    Marino de Luca

    2010-07-01

    Full Text Available Nella nota vengono sintetizzate le principali conclusioni cui è pervenuta una ricerca finanziata dalla Camera di Commercio di Napoli e realizzata da Uniontrasporti e dal dipartimento di Ingegneria dei trasporti della Federico II. Il lavoro ha riguardato il settore prevalente della city logistics e cioè il rifornimento di quegli esercizi della rete commerciale al dettaglio che non dispongono di organizzazioni autonome già oggi sotto controllo come, ad esempio, hanno la Grande distribuzione, il trasporto dei giornali, dei prodotti farmaceutici, degli ortofrutticoli ecc. Il lavoro è stato caratterizzato da alcune specificità: • è basato su una conoscenza quantitativa diretta della domanda di rifornimento merci nell’area metropolitana di Napoli ottenuta da una rilevazione campionaria sul campo (2000 interviste • si riferisce ad un’area metropolitana e non ad una singola città, prevedendo che una diversa organizzazione del rifornimento deve riguardare tutti gli esercizi del territorio sul quale operano le aziende del settore, territorio che, per le grandi città, coincide con l’area metropolitana • prevede la realizzazione di due tipologie di “nodi” nei quali effettuare manipolazione delle merci: centri merci inseriti negli interporti dell’area per i flussi provenienti o destinati in zone molto distanti (Italia del centro, del nord e del sud e transit point “di quartiere” dai quali partire per raggiungere il destinatario finale con mezzi a mano o ad emissione zero o anche con ritiro a cura del destinatario stesso. Le principali dimensioni della domanda desunte dall’indagine eseguita possono essere sintetizzate nelle seguenti cifre: 27.000 consegne/giorno-medio (0,87 per esercizio per 260.000 colli (9,72 a consegna su tutto il territorio della provincia; il 44% destinate alla città di Napoli, il 45% destinato al resto dell’area metropolitana di Napoli e l’11% al resto della provincia; il 34% proviene invece da

  14. Digital particle image thermometry/velocimetry: a review

    Energy Technology Data Exchange (ETDEWEB)

    Dabiri, Dana [University of Washington, Department of Aeronautics and Astronautics, Seattle, WA (United States)

    2009-02-15

    Digital particle image thermometry/velocimetry (DPIT/V) is a relatively new methodology that allows for measurements of simultaneous temperature and velocity within a two-dimensional domain, using thermochromic liquid crystal tracer particles as the temperature and velocity sensors. Extensive research has been carried out over recent years that have allowed the methodology and its implementation to grow and evolve. While there have been several reviews on the topic of liquid crystal thermometry (Moffat in Exp Therm Fluid Sci 3:14-32, 1990; Baughn in Int J Heat Fluid Flow 16:365-375, 1995; Roberts and East in J Spacecr Rockets 33:761-768, 1996; Wozniak et al. in Appl Sci Res 56:145-156, 1996; Behle et al. in Appl Sci Res 56:113-143, 1996; Stasiek in Heat Mass Transf 33:27-39, 1997; Stasiek and Kowalewski in Opto Electron Rev 10:1-10, 2002; Stasiek et al. in Opt Laser Technol 38:243-256, 2006; Smith et al. in Exp Fluids 30:190-201, 2001; Kowalewski et al. in Springer handbook of experimental fluid mechanics, 1st edn. Springer, Berlin, pp 487-561, 2007), the focus of the present review is to provide a relevant discussion of liquid crystals pertinent to DPIT/V. This includes a background on liquid crystals and color theory, a discussion of experimental setup parameters, a description of the methodology's most recent advances and processing methods affecting temperature measurements, and finally an explanation of its various implementations and applications. (orig.)

  15. Peak-locking reduction for particle image velocimetry

    International Nuclear Information System (INIS)

    Michaelis, Dirk; Wieneke, Bernhard; Neal, Douglas R

    2016-01-01

    A parametric study of the factors contributing to peak-locking, a known bias error source in particle image velocimetry (PIV), is conducted using synthetic data that are processed with a state-of-the-art PIV algorithm. The investigated parameters include: particle image diameter, image interpolation techniques, the effect of asymmetric versus symmetric window deformation, number of passes and the interrogation window size. Some of these parameters are found to have a profound effect on the magnitude of the peak-locking error. The effects for specific PIV cameras are also studied experimentally using a precision turntable to generate a known rotating velocity field. Image time series recorded using this experiment show a linear range of pixel and sub-pixel shifts ranging from 0 to  ±4 pixels. Deviations in the constant vorticity field (ω z ) reveal how peak-locking can be affected systematically both by varying parameters of the detection system such as the focal distance and f -number, and also by varying the settings of the PIV analysis. A new a priori technique for reducing the bias errors associated with peak-locking in PIV is introduced using an optical diffuser to avoid undersampled particle images during the recording of the raw images. This technique is evaluated against other a priori approaches using experimental data and is shown to perform favorably. Finally, a new a posteriori anti peak-locking filter (APLF) is developed and investigated, which shows promising results for both synthetic data and real measurements for very small particle image sizes. (paper)

  16. Lezioni di Cosmologia Teorica

    CERN Document Server

    Gasperini, Maurizio

    2012-01-01

    Il libro è basato sulle lezioni attualmente tenute dall'autore presso l’Università di Bari, ed è progettato in modo da rappresentare un testo di riferimento il più possibile moderno, completo e autosufficiente per i corsi semestrale di Cosmologia, Astrofisica o Fisica Astroparticellare che compaiono nel piano di studi della Laurea Magistrale in Fisica e in Astronomia. Contiene gli elementi di base della cosmologia relativistica, del modello cosmologico standard e del suo completamento inflazionario. E' organizzato per servire da traccia ad un corso di cosmologia di stampo teorico, ma cerca di non perdere mai di vista il confronto con i principali risultati osservativi: molta attenzione viene infatti dedicata alla fenomenologia dei fondi cosmici, e in particolare alla  radiazione gravitazionale fossile perché la sua rivelazione, diretta o indiretta, potrebbe dare indicazioni  cruciali sulla scelta del corretto modello per l'Universo primordiale. Non mancano infine alcuni accenni ad argomenti di inter...

  17. Sintesi stereoselettiva di piridilammine

    OpenAIRE

    Chelucci, Giorgio Adolfo; Baldino, Salvatore; Pinna, Gérard Aimé; Soccolini, Francesco

    2006-01-01

    Ammino piridine chirali hanno dimostrato la loro validità come leganti per la formazione di complessi metallici utilizzati nella catalisi asimmetrica. Tra i possibili approcci alla sintesi di questi composti noi abbiamo investigato la riduzione diastereoselettiva di N-sostituite (p-totil e tert-butil) piridil chetimmine con una serie di agenti riducenti (NaBH4, L-Selectride, DIBAL, 9-BBN) in diverse condizioni di reazione.

  18. Principi di Marketing

    OpenAIRE

    P. Kotler; G. Armstrong; F. Ancarani; M. Costabile

    2015-01-01

    Principi di marketing propone un quadro dei processi di gestione del marketing relativamente innovativo, ispirato a un modello rigoroso e semplice al tempo stesso: il valore, dei clienti, per i clienti e delle relazioni con i clienti. È su questo modello che vengono declinati i princìpi del marketing e che se ne progettano le strategie – segmentazione, targeting e posizionamento – da cui hanno origine le scelte di differenziazione di prodotti, marche, modalità di distribuzione e comunicazione...

  19. Il SIT del Servizio Geologico d’Italia implementa i contenuti La banca dati dei sondaggi profondi per la ricerca di idrocarburi

    Directory of Open Access Journals (Sweden)

    Marco Pantaloni

    2007-04-01

    Full Text Available Il Servizio Geologico d’Italia - Dipartimento Difesa del Suolo, ha raccolto l’archivio storico dei pozzi per ricerca petrolifera perforati in Italia. Tale possibilità ci è stata consentita grazie alla cortese collaborazione dell’Ufficio Nazionale Minerario per gli Idrocarburi e la Geotermia (UNMIG della Direzione Generale dell’Energia e delle Risorse Minerarie (DGERM del Ministero dello Sviluppo Economico. Nell’archivio sono contenuti tutti i dati dell’attività di esplorazione e produzione degli idrocarburi in Italia depositati presso l’UNMIG dal 1957 a oggi, e che per legge possono essere resi pubblici dopo un anno dalla cessazione del titolo minerario della società che li ha realizzati.

  20. Iced airfoil separation bubble measurements by particle image velocimetry

    Science.gov (United States)

    Jacobs, Jason J.

    Not long after the birth of aviation, pilots began to recognize the dangers posed by aircraft icing. Since that time, research has improved the awareness of this problem and the scientific understanding of the associated aerodynamic impacts, however, few studies have involved detailed, quantitative, flowfield measurements. For this reason, the current investigation was conducted in which high spatial-resolution flowfield measurements were acquired of a NACA 0012 airfoil with two- and three-dimensional, simulated, leading-edge, horn-ice accretions utilizing particle image velocimetry (PIV). These measurements complemented existing iced airfoil performance measurements, revealed previously unknown details regarding the structure and behavior of these flowfields, and could potentially facilitate the development and improvement of computational schemes used to predict largely separated flows, including that of an iced airfoil near stall. Previous iced airfoil investigations have demonstrated somewhat reduced aerodynamic penalties resulting from a three-dimensional ice simulation, compared to those of a two-dimensional ice simulation of a representative cross section. Correspondingly, the current measurements revealed accelerated transition of the separated shear layer emanating from a three-dimensional ice simulation and therefore enhanced pressure recovery and reduced mean separation bubble length, each relative to the flowfield of a representative two-dimensional ice simulation. These effects appeared to result from the quasi-steady distribution of discrete, streamwise vortices which aided the turbulent entrainment of fluid from the recirculation region of the three-dimensional ice simulation separation bubble flowfield. These vortices were generated by a streamwise-vortex instability excited by roughness along the three-dimensional ice simulation and produced spanwise-cell structures throughout this flowfield, as well as significant spanwise variation in peak

  1. Taratura di un 'apparecchiatura per misura di piccole percentuali di uranio in soluzione acida di acqua distillata

    Directory of Open Access Journals (Sweden)

    d. Diana

    1965-06-01

    Full Text Available Si descrive una tecnica elio permette di misurare ilnumero di atomi di Uranio di una soluzione, con un errore non superioreal 10%.Il sistema consiste in un tubo di Geiger (Philips 18503 sistemato inun contenitore di vetro nel quale viene diluita una certa quantità di peso dinitrato di Uranile, misurato con una precisione migliore dell'1%. Al variaredella diluizione si registra il numero di particelle che il Geiger conta, e quindisi riporta in grafico. Da questi per diverse quantità di sale sciolto si determinala retta di taratura.

  2. Effect of non-Poisson samples on turbulence spectra from laser velocimetry

    Science.gov (United States)

    Sree, Dave; Kjelgaard, Scott O.; Sellers, William L., III

    1994-01-01

    Spectral analysis of laser velocimetry (LV) data plays an important role in characterizing a turbulent flow and in estimating the associated turbulence scales, which can be helpful in validating theoretical and numerical turbulence models. The determination of turbulence scales is critically dependent on the accuracy of the spectral estimates. Spectral estimations from 'individual realization' laser velocimetry data are typically based on the assumption of a Poisson sampling process. What this Note has demonstrated is that the sampling distribution must be considered before spectral estimates are used to infer turbulence scales.

  3. Testimonianze di vittime degli anni di piombo

    DEFF Research Database (Denmark)

    Cecchini, Leonardo

    Testimonianze di vittime degli anni di piombo In un articolo pubblicato nel 2008 sulla webzine Nazione indiana Christian Raimo criticava quello che poi Giovanni De Luna qualche anno dopo nel suo libro La Repubblica del dolore (2011) ha chiamato “paradigma vittimario”; cioè la presenza predominante...

  4. Multipurpose Pressure Vessel Scanner and Photon Doppler Velocimetry

    Science.gov (United States)

    Ellis, Tayera

    2015-01-01

    Critical flight hardware typically undergoes a series of nondestructive evaluation methods to screen for defects before it is integrated into the flight system. Conventionally, pressure vessels have been inspected for flaws using a technique known as fluorescent dye penetrant, which is biased to inspector interpretation. An alternate method known as eddy current is automated and can detect small cracks better than dye penetrant. A new multipurpose pressure vessel scanner has been developed to perform internal and external eddy current scanning, laser profilometry, and thickness mapping on pressure vessels. Before this system can be implemented throughout industry, a probability of detection (POD) study needs to be performed to validate the system’s eddy current crack/flaw capabilities. The POD sample set will consist of 6 flight-like metal pressure vessel liners with defects of known size. Preparation for the POD includes sample set fabrication, system operation, procedure development, and eddy current settings optimization. For this, collaborating with subject matter experts was required. This technical paper details the preparation activities leading up to the POD study currently scheduled for winter 2015/2016. Once validated, this system will be a proven innovation for increasing the safety and reliability of necessary flight hardware.Additionally, testing of frangible joint requires Photon Doppler Velocimetry (PDV) and Digital Image Correlation instrumentation. There is often noise associated with PDV data, which necessitates a frequency modulation (FM) signal-to-noise pre-test. Generally, FM radio works by varying the carrier frequency and mixing it with a fixed frequency source, creating a beat frequency which is represented by audio frequency that can be heard between about 20 to 20,000 Hz. Similarly, PDV reflects a shifted frequency (a phenomenon known as the Doppler Effect) from a moving source and mixes it with a fixed source frequency, which results in

  5. Problemi di Fisica

    CERN Document Server

    Fazio, Michelangelo

    2008-01-01

    L’introduzione delle lauree triennali ha in molti casi costretto i docenti a ridurre drasticamente il numero di ore di insegnamento e quindi l’estensione dei programmi dei corsi di Fisica. In questo volumetto l'autore si è proposto di esporre sinteticamente ma con il massimo rigore possibile il corso di Fisica Generale I evitando le dimostrazioni delle leggi fisiche, ma dando la priorità alle applicazioni di tali leggi e allo svolgimento di esercizi che in genere viene trascurato in molti corsi. Ha cercato pertanto di presentare i fenomeni fisici sottolineando, dove possibile, la loro presenza nella vita quotidiana e le loro più semplici e immediate applicazioni, consentendo in tal modo agli studenti di vedere la Fisica non più come una interminabile serie di formule ma come un nuovo modo di interpretare e di capire i fenomeni naturali inanimati (del resto non dobbiamo dimenticare che il termine greco da cui deriva il suo nome è fisis, fisis, ovvero natura). Il contenuto è completo, comprendendo anc...

  6. Il Cratilo di Platone

    Directory of Open Access Journals (Sweden)

    Maria Chiara Pievatolo

    2015-06-01

    Full Text Available La guida ipertestuale alla lettura del Cratilo di Platone composta per gli studenti della facoltà di Scienze politiche dell’università di Pisa è ora visibile a tutti qui. L’ipertesto ha tratto vantaggio dall’Introduzione alla linguistica generale del professor Manuel Barbera dell’università...

  7. Particle Image Velocimetry and Computational Fluid Dynamics Analysis of Fuel Cell Manifold

    DEFF Research Database (Denmark)

    Lebæk, Jesper; Blazniak Andreasen, Marcin; Andresen, Henrik Assenholm

    2010-01-01

    The inlet effect on the manifold flow in a fuel cell stack was investigated by means of numerical methods (computational fluid dynamics) and experimental methods (particle image velocimetry). At a simulated high current density situation the flow field was mapped on a 70 cell simulated cathode...

  8. Comparative assessment of pressure field reconstructions from particle image velocimetry measurements and Lagrangian particle tracking

    NARCIS (Netherlands)

    van Gent, P.L.; Michaelis, D; van Oudheusden, B.W.; Weiss, P.E.; de Kat, R.; Laskari, A.; Jeon, Y.J.; David, L; Schanz, D; Huhn, F.; Gesemann, S; Novara, M.; McPhaden, C.; Neeteson, N. J.; Rival, David E.; Schneiders, J.F.G.; Schrijer, F.F.J.

    2017-01-01

    A test case for pressure field reconstruction from particle image velocimetry (PIV) and Lagrangian particle tracking (LPT) has been developed by constructing a simulated experiment from a zonal detached eddy simulation for an axisymmetric base flow at Mach 0.7. The test case comprises sequences

  9. QUANTITATIVE FLOW-ANALYSIS AROUND AQUATIC ANIMALS USING LASER SHEET PARTICLE IMAGE VELOCIMETRY

    NARCIS (Netherlands)

    STAMHUIS, EJ; VIDELER, JJ

    Two alternative particle image velocimetry (PIV) methods have been developed, applying laser light sheet illumination of particle-seeded flows around marine organisms, Successive video images, recorded perpendicular to a light sheet parallel to the main stream, were digitized and processed to map

  10. Analysis of propeller-induced ground vortices by particle image velocimetry

    NARCIS (Netherlands)

    Yang, Y.; Sciacchitano, A.; Veldhuis, L.L.M.; Eitelberg, G.

    2017-01-01

    Abstract: The interaction between a propeller and its self-induced vortices originating on the ground is investigated in a scaled experiment. The velocity distribution in the flow field in two different planes containing the self-induced vortices is measured by particle image velocimetry (PIV).

  11. Endovascular Device Testing with Particle Image Velocimetry Enhances Undergraduate Biomedical Engineering Education

    Science.gov (United States)

    Nair, Priya; Ankeny, Casey J.; Ryan, Justin; Okcay, Murat; Frakes, David H.

    2016-01-01

    We investigated the use of a new system, HemoFlow™, which utilizes state of the art technologies such as particle image velocimetry to test endovascular devices as part of an undergraduate biomedical engineering curriculum. Students deployed an endovascular stent into an anatomical model of a cerebral aneurysm and measured intra-aneurysmal flow…

  12. Three-dimensional particle image velocimetry in a generic can-type gas turbine combustor

    CSIR Research Space (South Africa)

    Meyers, BC

    2009-09-01

    Full Text Available The three-dimensional flow field inside a generic can-type, forward flow, experimental combustor was measured. A stereoscopic Particle Image Velocimetry (PIV) system was used to obtain the flow field of the combustor in the non-reacting condition...

  13. Rainbow particle imaging velocimetry for dense 3D fluid velocity imaging

    KAUST Repository

    Xiong, Jinhui

    2017-07-21

    Despite significant recent progress, dense, time-resolved imaging of complex, non-stationary 3D flow velocities remains an elusive goal. In this work we tackle this problem by extending an established 2D method, Particle Imaging Velocimetry, to three dimensions by encoding depth into color. The encoding is achieved by illuminating the flow volume with a continuum of light planes (a

  14. Particle imaging velocimetry experiments and lattice-Boltzmann simulations on a single sphere settling under gravity

    NARCIS (Netherlands)

    Ten Cate, A.; Nieuwstad, C.H.; Derksen, J.J.; Van den Akker, H.E.A.

    2002-01-01

    A comparison is made between experiments and simulations on a single sphere settling in silicon oil in a box. Cross-correlation particle imaging velocimetry measurements were carried out at particle Reynolds numbers ranging from 1.5 to 31.9. The particle Stokes number varied from 0.2 to 4 and at

  15. Particle image velocimetry measurements and numerical modeling of a saline density current

    CSIR Research Space (South Africa)

    Gerber, G

    2011-03-01

    Full Text Available Particle image velocimetry scalar measurements were carried out on the body of a stably stratified density current with an inlet Reynolds number of 2,300 and bulk Richardson number of 0.1. These measurements allowed the mass and momentum transport...

  16. Three-component particle image velocimetry in a generic can-type gas turbine combustor

    CSIR Research Space (South Africa)

    Meyers, Bronwyn C

    2012-11-01

    Full Text Available -1 Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy November 2012/ Vol. 226(7) Three-componentParticle Image Velocimetry in a Generic Can-type Gas Turbine Combustor B C Meyers 1, 2* , G C Snedden 1 , J P...

  17. Fluid Flow Characterization of High Turbulent Intensity Compressible Flow Using Particle Image Velocimetry

    Science.gov (United States)

    2015-08-01

    completed in order to begin further experimentation. A 10 kHz Time Resolved Particle Image Velocimetry (TR-PIV) system and a 3 kHz Planer Laser ...9 2.3.2 Planar Laser Induced Fluorescence (PLIF...35 Figure 4.4: Solenoid valve (a), proportional control valve (b) and flowmeter (c) ...................................... 36 Figure 4.5

  18. Drag coefficient accuracy improvement by means of particle image velocimetry for a transonic NACA0012 airfoil

    International Nuclear Information System (INIS)

    Ragni, D; Van Oudheusden, B W; Scarano, F

    2011-01-01

    A method to improve the reliability of the drag coefficient computation by means of particle image velocimetry measurements is made using experimental data acquired on a NACA0012 airfoil tested in the transonic regime, using the combination of a variable pulse separation with a new high-order Poisson spectral pressure reconstruction algorithm. (technical design note)

  19. Application of stereoscopic particle image velocimetry to studies of transport in a dusty (complex) plasma

    International Nuclear Information System (INIS)

    Thomas, Edward Jr.; Williams, Jeremiah D.; Silver, Jennifer

    2004-01-01

    Over the past 5 years, two-dimensional particle image velocimetry (PIV) techniques [E. Thomas, Jr., Phys. Plasmas 6, 2672 (1999)] have been used to obtain detailed measurements of microparticle transport in dusty plasmas. This Letter reports on an extension of these techniques to a three-dimensional velocity vector measurement approach using stereoscopic PIV. Initial measurements using the stereoscopic PIV diagnostic are presented

  20. Basics and principles of particle image velocimetry (PIV) for mapping biogenic and biologically relevant flows

    NARCIS (Netherlands)

    Stamhuis, Eize J.

    2006-01-01

    Particle image velocimetry (PIV) has proven to be a very useful technique in mapping animal-generated flows or flow patterns relevant to biota. Here, theoretical background is provided and experimental details of 2-dimensional digital PIV are explained for mapping flow produced by or relevant to

  1. The application of particle image velocimetry for the analysis of high-speed craft hydrodynamics

    NARCIS (Netherlands)

    Jacobi, G.; Thill, C.H.; Huijsmans, R.H.M.; Huijsmans, R.H.M.

    2016-01-01

    The particle image velocimetry (PIV) technique has become a reliable method for capturing the velocity field and its derivatives, even in complex flows and is now also widely used for validation of numerical codes. As the imaging system is sensitive to vibrations, the application in environments

  2. Equazione di Dirac

    CERN Document Server

    Monti, Dalida

    1996-01-01

    Relativamente poco noto al gran pubblico, il premio Nobel Paul Adrien Maurice Dirac appartiene a quel gruppo di uomini di ingegno che nei primi decenni del secolo contribuirono a dare alla nostra concezione del mondo fisico la sua impronta attuale. Assolutamente cruciali, per una valutazione dell'opera di Dirac, sono gli anni compresi tra il 1925 e il 1931: un periodo in cui il fisico fornisce la prima spiegazione chiara e coerente delle proprietà di spin dell'elettrone (equazione di Dirac) e perviene, in forza della pura deduzione matematica, alla scoperta dell'esistenza dell'elettrone positivo o positrone.

  3. Characterization of an evaporating direct-injected gasoline spray using laser-induced exciplex fluorescence and particle image velocimetry techniques

    Energy Technology Data Exchange (ETDEWEB)

    Dong-Seok Choi; Choongsik Bae [Korea Advanced Institute of Science and Technology, Taejon (Korea). Dept. of Mechanical Engineering; Duck-Jool Kim [Pusan National University (Korea). School of Mechanical Engineering

    2004-07-01

    The purpose of this study is to characterize an evaporating direct-injected (DI) gasoline spray from a high-pressure swirl injector using the laser-induced exciplex fluorescence (LIEF) technique and particle image velocimetry (PIV). A fluorobenzene/diethylmethylamine (DEMA) system was used as the exciplex-forming dopants. The behaviour of the liquid and vapour phases was analysed by image processing. For the analysis of vorticity inside the spray, droplet velocity data obtained by PIV were used. The experiments were performed at two ambient temperatures (293 and 473 K) and three different ambient pressures (0.1, 0.5 and 1.0 MPa). It was found that ambient temperature had a significant effect on the axial and radial growth of the liquid phase of the evaporating spray at atmospheric pressure while it had little effect under elevated pressures. Radial growth of the vapour phase of the evaporating spray was more dominant than axial growth under high temperature and pressure conditions. As the ambient pressure was elevated, the liquid phase of the spray transformed from a hollow cone to a solid cone of bell shape, while the vapour phase varied from a widespread distribution to a compact shape with a locally richer mixture. The evaporating spray could be divided into two spray regions from the analysis of vorticity and the distributions of liquid and vapour phases. The cone region (penetrations of 0.3-0.5) was mainly liquid phase and disappeared rapidly at the end of injection. The mixing region contained the active interaction between entrained air and fuel vapour. (author)

  4. Single-cycle Pulse Synthesis by Coherent Superposition of Ultra-broadband Optical Parametric Amplifiers

    Science.gov (United States)

    2011-08-01

    Research Council Centre of Excellence, School of Physics, University of Sydney, NSW 2006, Australia, 3IFN-CNR, Dipartimento di Fisica , Politecnico di...Cristian Manzoni, 1,* Jeffrey Moses, 2 Franz X. Kärtner, 2,3 and Giulio Cerullo 1 1IFN-CNR, Dipartimento di Fisica , Politecnico di Milano, Piazza L...Cerullo1 1 IFN-CNR, Dipartimento di Fisica , Politecnico di Milano, Piazza L. Da Vinci 32, 20133 Milano, Italy 2 Department of Electrical

  5. Numerical Optimization.

    Science.gov (United States)

    1988-01-01

    TASK AREA & WORK UNIT NUMBERS Dipartimento di Matematica -G.--iattelnuoz .’ Universita di Roma "La Sapienze" rlnlRr% Pnmaq (Tt-al’g) I$. CONTROLLING...guaranteed. 3. Adminisrtrative actions The following investigators are working on the contract: (i) Francesco Zirilli Dipartimento di Matematica "G...Castelnuovo" Universiti di Roma "La Sapienza" 00185 Romna (Italy) (ii) Filippo Aluffi-Pentini Dipartimento di Matematica Universiti di Barn 80125 Bari (Italy

  6. X-ray Observations of the Sun: Solar Flares and their Impact on the Geophysical Space

    Science.gov (United States)

    2012-07-01

    Michele Piana Universita’ di Genova Dipartimento Di Matematica Via Dodecaneso 35 Genova, Italy 16146 EOARD Grant 09-3050 Report...ORGANIZATION NAME(S) AND ADDRESS(ES) Universita’ di Genova Dipartimento Di Matematica Via Dodecaneso 35 Genova, Italy 16146 8. PERFORMING...Piana, DIpartimento di Matematica , Universita’ di Genova Scientific Report The aim of the present project was to apply computational tools based on

  7. Design e valutazione di una esperienza di mobile learning

    Directory of Open Access Journals (Sweden)

    Marco Arrigo

    2008-01-01

    Full Text Available Analisi dello sviluppo scientifico e tecnologico nel campo di mobile learning, con particolare riferimento ai problemi di progettazione e valutazione nelle esperienze. Vengono analizzate le caratteristiche di metodologia didattica innovativa insieme a delle proposte per strumenti operativi concreti che consentano di progettare interventi didattici di mobile learning.

  8. Esercizi scelti di algebra

    CERN Document Server

    Chirivì, Rocco; Dvornicich, Roberto

    2017-01-01

    Questo libro – primo di due volumi -  presenta oltre 250 esercizi scelti di algebra ricavati dai compiti d'esame dei corsi di Aritmetica tenuti dagli autori all'Università di Pisa. Ogni esercizio viene presentato con una o più soluzioni accuratamente redatte con linguaggio e notazioni uniformi. Caratteristica distintiva del libro è che gli esercizi proposti sono tutti diversi uno dall'altro e le soluzioni richiedono sempre una piccola idea originale; ciò rende il libro unico nel genere. Gli argomenti di questo primo volume sono: principio d'induzione, combinatoria, congruenze, gruppi abeliani, anelli commutativi, polinomi, estensioni di campi, campi finiti. Il libro contiene inoltre una dettagliata sezione di richiami teorici e può essere usato come libro di riferimento per lo studio. Una serie di esercizi preliminari introduce le tecniche principali da usare per confrontarsi con i testi d'esame proposti. Il volume è rivolto a tutti gli studenti del primo anno dei corsi di laur ea in Matematica e Inf...

  9. Autobiografia di un fisico

    CERN Document Server

    Born, Max

    1980-01-01

    Questa non è solo un'autobiografia scientifica. Il ritratto che Max Born ci offre di se stesso va oltre il profilo dell'uomo di scienza, che pure è stato tra i maggiori del nostro secolo. Di lui veniamo a sapere tutto ciò che occorre per accostarsi alle teorie che gli valsero il premio Nobel, ma anche i tratti di una normale vita borghese nella quale si intrecciavano le influenze dell'ambiente intellettuale e commerciale. Il tono è quello di una rievocazione piana e distesa che ci accompagna per le varie fasi della carriera dello studente, del docente, dello scienziato, nelle università tedesche e inglesi, negli anni delle persecuzioni naziste, alle quali l'ebreo Max Born ebbe la fortuna di sopravvivere, e nel dopoguerra, quando egli tornò in Germania e seppe dare un contributo di idee e di iniziative ai movimenti pacifisti. E' la lunga e operosa vita di un uomo di genio, del quale si ricorda la profonda umanità, la vastità degli interessi culturali, l'acutezza dei giudizi sulle persone, sulle vicend...

  10. Journal of Genetics | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Istituto di Scienze Marine, Sezione di Venezia, CNR, Castello 1364/a, 30122 Venezia, Italy; Dipartimento di Biologia Animale, Università di Palermo, Via Archirafi 18, 90123 Palermo, Italy; Dipartimento di Scienze Ambientali, Università “Ca' Foscari”, Castello 2737/b - 30122 Venezia, Italy; Istituto di Ecologia e Biologia ...

  11. Journal of Astrophysics and Astronomy | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Dipartimento di Fisica 'G. Galilei', Università di Padova 35131 Padova, Italy. N.F.N. Sezione di Padova 35131 Padova, Italy. Dipartimento di Fisica, Università di Perugia 06100 Perugia, Italy. Agenzia Spaziale Italiana & Istituto Nazionale di Astrofisica, Rome, Italy. Tuorla Obs., Department of Physics and ...

  12. Introduzione alle teorie di gauge

    CERN Document Server

    Cabibbo, Nicola; Benhar, Omar

    2016-01-01

    "Introduzione alle Teorie di Gauge" completa la serie di tre volumi basati sulle lezioni dei corsi di Meccanica Quantistica Relativistica, Interazioni Elettrodeboli e Teorie di Gauge, impartite dagli autori agli studenti delle Lauree Magistrali in Fisica e Astronomia & Astrofisica dell'Universita "La Sapienza" di Roma, nell'arco di qualche decennio. L'obiettivo principale del volume è di introdurre i concetti di base della rinormalizzazione nella teoria quantistica dei campi e i fondamenti delle moderne teorie di Gauge. Anche se collegato ai volumi precedenti, il libro si presta ad una lettura indipendente, che presume solo conoscenze generali di relativita speciale, della seconda quantizzazione e della fenomenologia delle interazioni elettrodeboli. Lo strumento di base è l'integrale sui cammini di Feynman, introdotto nei capitoli iniziali e sistematicamente impiegato nel seguito. L'esposizione segue un percorso pedagogico, che parte dal caso semplice dell'ampiezza di transizione in meccanica quantistic...

  13. RICERCHE DI STATISTICA METEOROLOGICA

    Directory of Open Access Journals (Sweden)

    EZIO ROSINI

    1956-06-01

    Full Text Available statistica
    non ha goduto di buona stampa nel passato anche recente; particolarmente
    poco apprezzata è stata la statistica meteorologica e climatologica.
    Occorre riconoscere che tale atteggiamento era almeno in
    parte frutto di un preconcetto errato sul significato della statistica, ma
    che d'altra parte la natura dei lavori di tal genere che venivano alla
    luce sembrava a volte confermare la giustezza del preconcetto. Il fatto
    è che una parte degli studiosi di meteorologia avvertiva più di altri,
    probabilmente per la propria stessa costituzione mentale, l'astrattezza
    dei metodi fisico-matematici applicati alla grandiosa e al tempo stesso
    minuta complessità dei fenomeni meteorologici, sentendo dunque maggiormente
    la necessità di far costante ricorso alla realtà delle osservazioni
    effettivamente eseguite.

  14. Dai bisogni di salute al consumo di risorse sanitarie in provincia di Bergamo: profilo degli indicatori di bisogno, domanda, offerta

    Directory of Open Access Journals (Sweden)

    A. Zucchi

    2003-05-01

    Full Text Available

    Introduzione: la complessità interpretativa dei dati relativi ad alcuni fenomeni sanitari a livello territoriale impone la necessità di uno strumento semplice di lettura “epidemiologica”; tale lettura si fonda sull’utilizzo di una serie di “indicatori”, fondamenta di un processo dinamico di monitoraggio temporale e spaziale in grado di descrivere sinteticamente fenomeni di per sé complessi, al fine di fornire al decisore un supporto sintetico ma scientificamente solido.

    Obiettivi: istituzione di un sistema di monitoraggio sanitario community-based; definizione di indicatori sanitari comparabili tramite un esame critico dei dati esistenti; sviluppo di metodologie per la raccolta e la validazione dei dati; supporto alla creazione di un sistema efficace e affidabile di trasferimento e scambio dei dati e degli indicatori stessi con uso spinto della tecnologia telematica; elaborazione di metodi e di strumenti necessari alla produzione di analisi e relazioni.

    Materiali e metodi: gli indicatori analizzati fanno riferimento
    all’elenco definito dal decreto ministeriale n. 27 del 12 dicembre 2001 “sistema di garanzie per il monitoraggio dell’assistenza sanitaria”. A questo elenco ne sono stati aggiunti altri, per un totale di 127, divisi in grandi capitoli tematici: assistenza sanitaria, assistenza distrettuale, assistenza ospedaliera, indicatori stato di salute, consumo di risorse sanitarie (cui è stato dato particolare enfasi, indicatori di domanda/accessibilità. Per definire infine un
    profilo di sintesi di questi grandi capitoli e delle relative
    eterogeneità territoriali si è successivamente applicata la tecnica statistica dello “z-score”.
    Risultati: le differenze emerse a livello distrettuale hanno permesso di disegnare una ‘mappa’ degli indicatori sanitari in provincia di Bergamo.

    Conclusioni:i risultati di

  15. Combined Lorentz force and ultrasound Doppler velocimetry in a vertical convection liquid metal flow

    Science.gov (United States)

    Zürner, Till; Vogt, Tobias; Resagk, Christian; Eckert, Sven; Schumacher, Jörg

    2017-11-01

    We report experimental studies on turbulent vertical convection flow in the liquid metal alloy gallium-indium-tin. Flow measurements were conducted by a combined use of local Lorentz force velocimetry (LLFV) and ultrasound Doppler velocimetry (UDV). It is known that the forced convection flow in a duct generates a force on the LLFV magnet system, that grows proportional to the flow velocity. We show that for the slower flow of natural convection LLFV retains this linear dependence in the range of micronewtons. Furthermore experimental results on the scaling of heat and momentum transport with the thermal driving are presented. The results cover a range of Rayleigh numbers 3 ×105 Deutsche Forschungsgemeinschaft under Grant No. GRK 1567.

  16. Improvement in the independence of relaxation method-based particle tracking velocimetry

    International Nuclear Information System (INIS)

    Jia, P; Wang, Y; Zhang, Y

    2013-01-01

    New techniques are developed to improve the independence of relaxation method-based particle tracking velocimetry (RM-PTV). Firstly, Delaunay tessellation (DT) is employed to form clusters of neighboring particles with similar motion in the same frame; and then a bidirectional calculation concept is adopted to improve the way of particle pairing. These new techniques are tested with both self-defined particle images and the particle image velocimetry standard synthetic particle images. The results indicate that the DT method performs well and efficiently in determining the particle clusters, and the particle pairing process is well optimized by the bidirectional calculation concept. With these methods, three computation parameters are eliminated, which makes RM-PTV more autonomous in applications. (paper)

  17. Pulsed operation of high-power light emitting diodes for imaging flow velocimetry

    International Nuclear Information System (INIS)

    Willert, C; Klinner, J; Moessner, S; Stasicki, B

    2010-01-01

    High-powered light emitting diodes (LED) are investigated for possible uses as light sources in flow diagnostics, in particular, as an alternative to laser-based illumination in particle imaging flow velocimetry in side-scatter imaging arrangements. Recent developments in solid state illumination resulted in mass-produced LEDs that provide average radiant power in excess of 10 W. By operating these LEDs with short duration, pulsed currents that are considerably beyond their continuous current damage threshold, light pulses can be generated that are sufficient to illuminate and image micron-sized particles in flow velocimetry. Time-resolved PIV measurements in water at a framing rate of 2kHz are presented. The feasibility of LED-based PIV measurements in air is also demonstrated

  18. Reti di città, mobilità e ambiente: il Preliminare di PTCP di Avellino

    Directory of Open Access Journals (Sweden)

    Carmela Gargiulo

    2010-02-01

    Full Text Available  L’articolo propone la lettura dei contenuti del Preliminare del PTCP di Avellino, un piano per molti aspetti innovativo, soprattutto per aver coniugato pianificazione di area vasta di tipo tradizionale e logica “strategica”. In particolare, l’articolo descrive idee guida, contenuti e strategie del piano orientate, prevalentemente, a stimolare lo sviluppo sostenibile di un’area in ritardo di sviluppo come la provincia irpina, attraverso la salvaguardia e valorizzazione delle risorse naturali e storico-culturali, la costruzione di reti di medie e piccole città e reti di mobilità alle diverse scale, da quella urbana a quella internazionale, e interventi sul sistema della mobilità. Nel 2004, ormai più di cinque anni fa, è stato adottato, a maggioranza assoluta (solo due gli astenuti, il Preliminare di Piano Territoriale di Coordinamento della Provincia di Avellino, dopo un lavoro di oltre due anni che ha visto impegnati gli uffici provinciali con due dipartimenti universitari. Il lavoro, che va ben oltre il significato e la valenza di un preliminare e che coniuga due pratiche di piano diverse (quella tradizionale e quella strategica ruota attorno a tre idee di fondo, tra loro strettamente interrelate, che costituiscono i criteri guida che finora ha inteso seguire la provincia di Avellino nell’attività di governo delle trasformazioni. Tali idee, quindi, costituiscono le fondamenta su cui è stato costruito il Preliminare e sono la griglia di specificazione delle strategie e degli obiettivi di piano. Esse sono alla base delle scelte elaborate per lo sviluppo compatibile del territorio, e sono riferibili alle azioni operative di trasformazione del territorio che gli Enti locali, cui è demandato tale compito, nel prossimo futuro dovranno affrontare. Le tre idee forza del Preliminare, descritte nel seguito, sono riferibili ai sistemi di risorse principali della provincia di Avellino, oggetto di una indagine analitico

  19. Assessment of Doppler velocimetry versus nonstress test in antepartum surveillance of high risk pregnancy

    OpenAIRE

    Nishi Choudhury; Barun Kumar Sharma; Bikram Kishor Kanungo; Ruby Yadav; Hafizur Rahman

    2017-01-01

    Background: High risk pregnancies increase the maternal and fetal morbidity and mortality; and there is a need for appropriate investigation which can diagnose it early and predicts the morbidity and mortality. The objectives of this study were to compare the efficacy of Doppler velocimetry studies and NST in predicting fetal compromise in utero and compare their ability in predicting the perinatal outcome in cases of high risk pregnancies. Methods: It was a prospective cross-sectional ho...

  20. Abnormal Doppler flow velocimetry in the growth restricted foetus as a predictor for necrotising enterocolitis.

    Directory of Open Access Journals (Sweden)

    Bhatt A

    2002-07-01

    Full Text Available BACKGROUND: Obstetric decision- making for the growth restricted foetus has to take into consideration the benefits and risks of waiting for pulmonary maturity and continued exposure to hostile intra-uterine environment. Necrotising Enterocolitis (NEC results from continued exposure to hostile environment and is an important cause of poor neonatal outcome. AIMS: To evaluate the predictive value of abnormal Doppler flow velocimetry of the foetal umbilical artery for NEC and neonatal mortality. SETTINGS AND DESIGN: A retrospective study carried out at a tertiary care centre for obstetric and neonatal care. MATERIALS AND METHOD: Seventy-seven neonates with birth weight less than 2000 gm, born over a period of 18 months were studied. These pregnancies were identified as having growth abnormalities of the foetus. Besides other tests of foetal well-being, they were also subjected to Doppler flow velocimetry of the foeto-placental vasculature. Obstetric outcome was evaluated with reference to period of gestation and route of delivery. The neonatal outcome was reviewed with reference to birth weight, Apgar scores and evidence of NEC. STATISTICAL ANALYSIS USED: Chi square test. RESULTS: In the group of patients with Absent or Reverse End Diastolic Frequencies (A/R EDF in the umbilical arteries, positive predictive value for NEC was 52.6%, (RR 30.2; OR 264. The mortality from NEC was 50%. When umbilical artery velocimetry did not show A/REDF, there were no cases of NEC or mortality. Abnormal umbilical or uterine artery flow increased the rate of caesarean section to 62.5% as compared to 17.6% in cases where umbilical artery flow was normal. CONCLUSION: In antenatally identified pregnancies at risk for foetal growth restriction, abnormal Doppler velocimetry in the form of A/REDF in the umbilical arteries is a useful guide to predict NEC and mortality in the early neonatal period.

  1. Tomographic Particle Image Velocimetry using Pulsed, High Power LED Volume Illumination

    OpenAIRE

    Buchmann, N. A.; Willert, C.; Soria, J.

    2011-01-01

    This paper investigates the use of high-power light emitting diode (LED) illumination in Particle Image Velocimetry (PIV) as an alternative to traditional laser-based illumination. The solid-state LED devices can provide averaged radiant power in excess of 10W and by operating the LEDs with short current pulses, considerably higher than in continuous operation, light pulses of sufficient energy suitable for imaging micron-sized particles can be generated. The feasibility of this LED-based ill...

  2. Lezioni di meccanica razionale con elementi di statica grafica

    CERN Document Server

    Sbrana, Francesco

    1950-01-01

    Elementi di calcolo vettoriale ; riduzione di un sistema qualunque di vettori applicati ; trattazione analitica dei sistemi di vettori applicati ; uso dei poligni funicolari per la composizione di più vettori applicati complanari ; vettori variabili ; cinematica del punto ; studio del moto di un punto in un piano in coordinate polari ; cinematica de sistemi rigidi ; moto di un sistema rigido con un punto fisso (moto rigido sferico) ; moto relativo ; sistemi di punti in general, vincoli ; concetti e postulati fondamentali della meccanica ; unità mecchaniche, omogeneità, modelli ; equilibrio di un punto e di un sistema di punti materiali ; statica dei solidi indeformabili (sistemi rigidi) ; sistemi deformabili, travature reticolari ; equilibrio dei poligoni funicolari e delle curve funicolari ; nozioni sull'attrito ; integrazione grafica ; baricentri ; momenti d'inerzia ; calcolo grafico dei momenti statici e dei momenti d'inerzia dei sistemi piani ; dinamica del punto libero ; dinamica del punto vincolato ;...

  3. Elaborazione didattica di Learning Objects.

    Directory of Open Access Journals (Sweden)

    Luigi Guerra

    2006-01-01

    Full Text Available L’idea di un modello didattico problematico per la realizzazione di Learning Objects riprende i temi del problematicismo pedagogico e si impegna a definire un’ipotesi formativa complessa capace di valorizzare la possibile positiva compresenza integrata di strategie didattiche diverse (finanche antitetiche ma componibili in una logica appunto di matrice problematicista. Il punto di partenza del modello proposto è rappresentato dalla opportunità di definire tre tipologie fondamentali di Learning Objects, rispettivamente centrati sull’oggetto, sul processo e sul soggetto dell’apprendimento.

  4. Velocimetry using scintillation of a laser beam for a laser-based gas-flux monitor

    Science.gov (United States)

    Kagawa, Naoki; Wada, Osami; Koga, Ryuji

    1999-05-01

    This paper describes a velocimetry system using scintillation of a laser-beam with spatial filters based on sensor arrays for a laser- based gas flux monitor. In the eddy correlation method, gas flux is obtained by mutual relation between the gas density and the flow velocity. The velocimetry system is developed to support the flow velocity monitor portion of the laser-based gas flux monitor with a long span for measurement. In order to sense not only the flow velocity but also the flow direction, two photo diode arrays are arranged with difference of a quarter period of the weighting function between them; the two output signals from the sensor arrays have phase difference of either (pi) /2 or -(pi) /2 depending on the sense of flow direction. In order to obtain the flow velocity and the flow direction instantly, an electronic apparatus built by the authors extracts frequency and phase from crude outputs of the pair of sensors. A feasibility of the velocimetry was confirmed indoors by measurement of the flow- velocity vector of the convection. Measured flow-velocity vector of the upward flow agreed comparatively with results of an ultrasonic anemometer.

  5. Development of two-dimensional velocity field measurement using particle tracking velocimetry on neutron radiography

    International Nuclear Information System (INIS)

    Saito, Y.; Mishima, K.; Suzuki, T.; Matsubayashi, M.

    2003-01-01

    The structures of liquid metal two-phase flow are investigated for analyzing the core meltdown accident of fast reactor. The experiments of high-density ratio two-phase flow for lead-bismuth molten metal and nitrogen gases are conducted to understand in detail. The liquid phase velocity distributions of lead-bismuth molten metal are measured by neutron radiography using Au-Cd tracer particles. The liquid phase velocity distributions are obtained usually by using particle image velocimetry (PIV) on the neutron radiography. The PIV, however is difficult to get the velocity vector distribution quantitatively. An image of neutron radiography is divided into two images of the bubbles and the tracer particles each in particle tracking velocimetry (PTV), which distinguishes tracer contents in the bubble from them in the liquid phase. The locations of tracer particles in the liquid phase are possible to determine by particle mask correlation method, in which the bubble images are separated from the tracer images by Σ-scaling method. The particle tracking velocimetry give a full detail of the velocity vector distributions of the liquid phase in two-phase flow, in comparison with the PIV method. (M. Suetake)

  6. Elementi di fisica teorica

    CERN Document Server

    Cini, Michele

    2006-01-01

    Le idee e le tecniche della Fisica Teorica del XX secolo (meccanica analitica, meccanica statistica, relatività e meccanica quantistica non relativistica) non sono più appannaggio esclusivo dei fisici. Ormai, specialmente con la recente introduzione di nuovi corsi di laurea, le conoscenze di base rientrano nel bagaglio culturale comune ai laureati in materie scientifiche e tecnologiche affini alla Fisica e alle sue applicazioni. Un laureato in queste materie non può non conoscere l’equazione E=mc2 e la media di Gibbs; inoltre deve avere i concetti e i metodi fondamentali della meccanica quantistica che ha cambiato la concezione del mondo ed è alla base della rivoluzione tecnologica in corso. Eppure quelle idee rimangono distanti dal comune modo di pensare e richiedono molto studio e un insegnamento ben mirato. La trattazione in questo libro, è meno formale rispetto ai tradizionali corsi di Istituzioni di Fisica Teorica. Lo scopo è comunque quello di raggiungere una reale comprensione dei concetti fisi...

  7. Elementi di chimica fisica

    CERN Document Server

    Atkins, Peter W

    1994-01-01

    Elementi di chimica physica mira a presentare i concetti e le tecniche basilari della materia. I primi trovano utilizzazione in molte altre branche della chimica - la biochimica, l'ingegneria chimica, e (sempre di più) le scienze biologiche e mediche - mentre la materia in sé mette a disposizione procedimenti idonei ad esprimere idee qualitative in forma quantitativa e verificabile.

  8. Le Fumarole di Vulcano

    OpenAIRE

    Chiodini, G.; Russo, M.

    2011-01-01

    In tempi storici l’Isola di Vulcano è stata interessata da numerose eruzioni. Come già detto l’ultima attività vulcanica è avvenuta fra il 1888 e il 1890. Da allora l’attività del vulcano è caratterizzata dalla presenza di numerose aree fumarolizzate...

  9. Studio del comportamento di agenti di contrasto in campi ultracustici per tecniche di ecografia diagnostica

    OpenAIRE

    BIAGIONI, ANGELO

    2011-01-01

    Il presente lavoro di ricerca è stato articolato intorno a temi attinenti l’ingegneria biomedica, riguardando, in particolare, lo studio del comportamento di agenti di contrasto in campi ultracustici per tecniche di ecografia diagnostica. Nell’ambito di tale settore scientifico, un ruolo di fondamentale importanza è svolto dalla diagnostica medica per immagini e in particolare dalle tecniche ecografiche. Queste ultime rappresentano un ottimo compromesso tra la pericolosità per l’organismo e l...

  10. Duality and Unified Analysis of Discrete Approximations in Structural Dynamics and Wave Propagation: Comparison of rho-method Finite Elements with kappa-method NURBS (Preprint)

    Science.gov (United States)

    2007-10-10

    Dipartimento di Meccanica Strutturale, Università degli Studi di Pavia cDipartimento di Matematica , Università degli Studi di Pavia dEuropean Centre...for Training and Research in Earthquake Engineering, Pavia eIstituto di Matematica Applicata e Tecnologie Informatiche del CNR, Pavia “Comparisons

  11. Book review. Gli animali, l'uomo e l'ambiente. (a cura di Giorgio Battelli, Raffaella Baldelli, Fabio Ostanello, Santino Prosperi

    Directory of Open Access Journals (Sweden)

    Manuel Graziani

    2013-12-01

    Full Text Available Da sempre i Servizi Veterinari Pubblici sono una componente poco conosciuta del Servizio Sanitario Nazionale, le loro prestazioni vengono spesso fruite in modo inconsapevole sia dalla popolazione che dall'amministrazione pubblica. È pleonastico ricordare che si tratta di attività sanitarie il cui scopo prevalente è quello di tutelare la salute animale e umana e di promuovere la produttività e il benessere delle popolazioni animali. Ma vale la pena ribadire che tali attività hanno un ruolo assai rilevante anche sotto il profilo economico e sociale. Questo corposo volume fa il punto sulle competenze che le diverse componenti professionali devono possedere. Un volume importante per comprendere la realtà veterinaria italiana, pubblica e privata, nato dal lavoro congiunto di figure di primo livello della medicina veterinaria del Paese: i curatori sono tutti docenti del Dipartimento di Scienze Mediche Veterinarie dell'Università di Bologna, convinti assertori del ruolo sociale della Medicina veterinaria, del concetto di Medicina/Salute unica e della necessità di migliorare l'aspetto formativo. I professori Battelli, Baldelli, Ostanello e Prosperi fanno parte di quella che viene definita la "Scuola bolognese di Sanità Pubblica Veterinaria" il cui fondatore è stato Adriano Mantovani (scomparso a marzo dello scorso anno, unanimemente considerato il Padre della SPV italiana e di cui vengono qui pubblicati 3 scritti e una breve scheda biografica che lo ricorda. Il volume è suddiviso in tre parti allo scopo di fornire al lettore un percorso interpretativo logico che si sviluppa verso la comprensione delle competenze e dei campi di attività dei Servizi Veterinari nel nostro Paese, fino a mettere in luce le sfide attuali e future che la SPV deve affrontare. Particolare attenzione viene posta nei confronti dell'evoluzione che tali attività sanitarie potranno avere nel prossimo futuro, in riferimento ai cambiamenti socio-economici, alle attivit

  12. Improvement of image velocimetry based on a spatio-temporal correlation method; Jikukan sokan ni motozuku ryushi gazo sokudoba keisokuho no kaiseki seino kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, H. [Tokuyama College of Technology, Yamaguchi (Japan); Arifuku, T. [Komatsu Ltd., Tokyo (Japan); Koga, K. [Yamaguchi University, Yamaguchi (Japan). Faculty of Engineering

    1998-05-31

    In the image velocimetry, it is generally required to detect the various velocity in each position of the flow field. But the maximum velocity which the usual velocimetry can detect has been limited in about 1 pixel per frame. Then, in order to measure the wide range of velocity vectors from the dynamic image, the improvement of performance in the image velocimetry based on a spatio-temporal correlation method would be attempted by enlarging the analytical region and by interpolating the new frame. The analytical performance of velocimetry was estimated by measuring the velocity from the flow dynamic image made artificially on the personal computer so as to simulate the flow of fluid containing a lot of small particles. As the results, the velocity range of the improved velocimetry became larger than that of the usual velocimetry. 21 refs., 13 figs., 1 tab.

  13. Cacciatori di particelle

    CERN Document Server

    Ne'eman, Yuval

    1988-01-01

    Capostipite dei "cacciatori di particelle" fu J.J. Thomson, il quale nel 1897 scoprì la prima particella subatomica, l'elettrone. Poco dopo, negli anni tra il 1910 e il 1932, veniva rivelata la natura del nucleo atomico, grazie al lavoro di Rutherford. Partendo da queste prime storiche conquiste della fisica, gli autori introducono gradualmente il lettore nel micromondo delle particelle: dall'elettroscopio a foglie d'oro al dualismo onda-particella, all'enigma di una asimmetria destra-sinistra in natura, all'invenzione dei grandi acceleratori. Poi tra la fine degli anni cinquanta e i primi anni sessanta, l'esplosione di nuove specie particellari sembra vanificare ogni speranza di spiegazione. Lo schema di classificazione introdotto nel 1964 da Ne'eman (e, indipendentemente, da Gell-Mann), pone fine a tale confusione, consentendo una sistemazione coerente: quella che porta al concetto di quark e alle ultime conquiste, teoriche e sperimentali. Oggi, che i fisici sono divenuti più "coltivatori" che "cacciatori...

  14. Note di fotonica

    CERN Document Server

    Degiorgio, Vittorio

    2012-01-01

    L’invenzione del laser ha generato una vera rivoluzione nella scienza e nella tecnologia e ha dato luogo alla nascita di una nuova disciplina chiamata Fotonica. Le più importanti applicazioni della Fotonica che hanno un impatto cruciale in molti ambiti della nostra vita sono le comunicazioni in fibra ottica su cui si basa il funzionamento di Internet e del traffico telefonico su grandi distanze, i dischi ottici (CD, DVD, Blue-ray), la sensoristica ottica di tipo industriale e ambientale, la lavorazione dei materiali, l’illuminazione con i LED e la chirurgia. Questo volume ha come obiettivo quello di colmare un vuoto nel panorama italiano di testi universitari riguardanti la Fotonica. Lo scopo principale è quello di esporre in modo sintetico ma rigoroso i concetti che stanno alla base del funzionamento del laser e della propagazione della luce nella materia, e di descrivere i principali componenti e dispositivi ottici e optoelettronici, quali le fibre ottiche, gli amplificatori, i modulatori e i rivelato...

  15. The Fermi Large Area Telescope on Orbit: Event Classification, Instrument Response Functions, and Calibration

    Science.gov (United States)

    2012-11-01

    Technology (KTH), AlbaNova, SE-106 91 Stockholm, Sweden 8 Università di Pisa and Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa, Italy...France 10 Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste, Italy 11 Dipartimento di Fisica , Università di Trieste, I-34127...Trieste, Italy 12 Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova, Italy; rando@pd.infn.it 13 Dipartimento di Fisica e

  16. Il libro di fisica

    CERN Document Server

    Asimov, Isaac

    1986-01-01

    Isaac Asimov, illustre studioso e brillante divulgatore scientifico, ma anche grandissimo scrittore di science fiction, ha costruito questa volta una vera e propria «biografia delle scienze fisiche». Il presente volume, che nel mondo anglosassone è diventato una «bibbia della fisica», ci introduce, in forma semplice ma rigorosa, ai segreti dei quasar e dei buchi neri, dei quark e degli acceleratori di particelle, dell'intelligenza artificiale e delle fonti di energia, sia essa quella «sporca» sia quella «pulita». Un vero, completo manuale, ma anche un «romanzo» affascinante sia per il profano sia per l'uomo di scienza.

  17. Note di fotonica

    CERN Document Server

    Degiorgio, Vittorio

    2016-01-01

    L’invenzione del laser ha generato una vera rivoluzione nella scienza e nella tecnologia e ha dato luogo alla nascita di una nuova disciplina chiamata Fotonica. Le applicazioni della Fotonica che hanno un impatto cruciale in molti ambiti della nostra vita sono le comunicazioni in fibra ottica su cui si basa il funzionamento di Internet e del traffico telefonico su grandi distanze, i dischi ottici (CD, DVD, Blu-ray), la sensoristica ottica di tipo industriale e ambientale, la lavorazione dei materiali e la chirurgia con il laser, l’illuminazione con i LED. Questa seconda edizione contiene diversi ampliamenti e modifiche al testo pubblicato nel 2012, che ha colmato un vuoto nel panorama italiano di testi universitari riguardanti la Fotonica. Dopo avere esposto in modo sintetico ma rigoroso i concetti che stanno alla base del funzionamento del laser e della propagazione della luce nella materia, sono descritti i principali componenti e dispositivi ottici e optoelettronici, quali le fibre ottiche, gli amplifi...

  18. Appunti di meccanica relativistica

    CERN Document Server

    Cattaneo, Carlo

    1972-01-01

    Gli assiomi della fisica classica ; esame di alcuni esperimenti ottici alla luce dei principi della fisica classica ; i fondamenti generali della relatività ; conferme sperimentali della cinematica relativistica ; dinamica del punto materiale.

  19. Il Bosone di Higgs

    CERN Multimedia

    Hemmer, Sabine

    2018-01-01

    Poster di ATLAS sul bosone di Higgs indirizzato al pubblico generico, che spiega il meccanismo di Brout-Englert-Higgs e la sua importanza. Spiega anche il ruolo del Bosone di Higgs, come viene cercato, il percorso della sua scoperta e cosa viene dopo la scoperta. Disponibile anche in Francese (http://cds.cern.ch/record/1697501) e Inglese (http://cds.cern.ch/record/1697389). Non esitate a utilizzarlo nelle sedi dei vostri Istituti e negli eventi divulgativi! Il poster è in formato A0. Cliccate sull'immagine per scaricare il .pdf ad alta qualità e stamparlo dove preferite. Per qualisasi domanda o commento potete contattare atlas-outreach-coordination@cern.ch

  20. Manuale di ottica

    CERN Document Server

    Giusfredi, Giovanni

    2015-01-01

    Questo libro costituisce un fondamento solido per la conoscenza dell’Ottica Fisica, presentando vari modi di trattare la propagazione di onde elettromagnetiche e indicando quali siano i metodi utili a specifici casi. Iniziando dall’elettromagnetismo, la riflessione, la rifrazione e la dispersione delle onde, espone argomenti quali l’Ottica Geometrica, l’Interferenza, la Diffrazione, la Coerenza, i fasci Laser, la Polarizzazione, la Cristallografia e l’Anisotropia. Tratta componenti ottici come lenti, specchi, prismi, interferometri classici, Fabry-Perot e cavità risonanti, multistrati dielettrici, filtri interferenziali e spaziali, reticoli di diffrazione, polarizzatori e lamine birifrangenti. Vi sono inoltre argomenti poco reperibili, come il metodo delle matrici 4x4 per lo studio di fronti d’onda generalmente astigmatici, i metodi numerici tramite FFT per il calcolo della diffrazione, e la Bi-anisotropia, che tratta relativisticamente l’attività ottica e gli effetti Faraday e Fresnel-Fizeau....

  1. Stress indotto dalla guida di autoveicoli: studio di parametri psicofisiologici

    Directory of Open Access Journals (Sweden)

    R. Vivoli

    2003-05-01

    Full Text Available

    La guida di un autoveicolo, specie in condizioni di intenso traffico o di cattive condizioni meteoclimatiche, è considerata uno dei principali fattori stressanti della vita odierna. Durante la guida si possono infatti osservare significative risposte simpatoadrenergiche e cardiovascolari con la comparsa anche di episodi coronarici. Tali risposte presentano un’ampia variabilità interindividuale in quanto sono influenzate da vari fattori (stile di vita, personalità etc..

    In questa rassegna, vengono presentati i principali risultati degli studi da noi condotti sulle risposte psicofisiologiche indotte dalla guida di diversi tipi di autoveicoli. In conducenti di autobus urbani è stato registrato un sensibile aumento del tasso urinario di adrenalina durante il turno lavorativo rispetto alla stessa fascia oraria di un giorno di riposo. Tale risposta adrenergica era esaltata dall’abitudine tabagica e dall’assunzione di caffè e bevande alcoliche. In soggetti che alla guida di camion coprono lunghe distanze, i più elevati tassi urinari di catecolamine e i più alti livelli di frequenza cardiaca sono stati registrati quando la guida era particolarmente stressante per la presenza di nebbia o di intenso traffico. In soggetti che partecipano, a livello amatoriale, a manifestazioni agonistiche di velocità su pista, abbiamo osservato che durante la gara, rispetto al periodo pre-gara, l’escrezione urinaria di catecolamine aumenta in misura molto rilevante. Analogamente a quanto osservato in autisti di camion, l’attivazione del sistema adrenergico è risultata direttamente associata ai livelli di ansietà. Dall’elettrocardiogramma dinamico è emerso che durante la gara la frequenza cardiaca raggiunge un valore medio di 163.5±7.4 battiti/min. (range: 146,180 battiti/min..

    Un significativo peggioramento della percezione visiva stereoscopica, con potenziale ricaduta negativa sulla performance dei guidatori, è stato osservato in

  2. Laboratory observations of sediment transport using combined particle image and tracking velocimetry (Conference Presentation)

    Science.gov (United States)

    Frank, Donya; Calantoni, Joseph

    2017-05-01

    Improved understanding of coastal hydrodynamics and morphology will lead to more effective mitigation measures that reduce fatalities and property damage caused by natural disasters such as hurricanes. We investigated sediment transport under oscillatory flow over flat and rippled beds with phase-separated stereoscopic Particle Image Velocimetry (PIV). Standard PIV techniques severely limit measurements at the fluid-sediment interface and do not allow for the observation of separate phases in multi-phase flow (e.g. sand grains in water). We have implemented phase-separated Particle Image Velocimetry by adding fluorescent tracer particles to the fluid in order to observe fluid flow and sediment transport simultaneously. While sand grains scatter 532 nm wavelength laser light, the fluorescent particles absorb 532 nm laser light and re-emit light at a wavelength of 584 nm. Optical long-pass filters with a cut-on wavelength of 550 nm were installed on two cameras configured to perform stereoscopic PIV to capture only the light emitted by the fluorescent tracer particles. A third high-speed camera was used to capture the light scattered by the sand grains allowing for sediment particle tracking via particle tracking velocimetry (PTV). Together, these overlapping, simultaneously recorded images provided sediment particle and fluid velocities at high temporal and spatial resolution (100 Hz sampling with 0.8 mm vector spacing for the 2D-3C fluid velocity field). Measurements were made under a wide range of oscillatory flows over flat and rippled sand beds. The set of observations allow for the investigation of the relative importance of pressure gradients and shear stresses on sediment transport.

  3. Comparison of Simultaneous PIV and Hydroxyl Tagging Velocimetry in Low Velocity Flows

    Science.gov (United States)

    Andre, Matthieu A.; Bardet, Philippe M.; Burns, Ross A.; Danehy, Paul M.

    2016-01-01

    Hydroxyl tagging velocimetry (HTV) is a molecular tagging velocimetry (MTV) technique that relies on the photo- dissociation of water vapor into OH radicals and their subsequent tracking using laser-induced fluorescence. At ambient temperature in air, the OH species lifetime is about 50 micro-s. The feasibility of using HTV for probing low- speed flows (a few m/s) is investigated by using an inert, heated gas as a means to increase the OH species lifetime. Unlike particle-based techniques, MTV does not suffer from tracer settling, which is particularly problematic at low speeds. Furthermore, the flow needs to be seeded with only a small mole fraction of water vapor, making it safer for both the user and facilities than other MTV techniques based on corrosive or toxic chemical tracers. HTV is demonstrated on a steam-seeded nitrogen jet at approximately 75 C in the laminar (Umean=3.31 m/s, Re=1,540), transitional (Umean=4.48 m/s, Re=2,039), and turbulent (Umean=6.91 m/s, Re=3,016) regimes at atmospheric pressure. The measured velocity profiles are compared with particle image velocimetry (PIV) measurements performed simultaneously with a second imager. Seeding for the PIV is achieved by introducing micron-sized water droplets into the flow with the steam; the same laser sheet is used for PIV and HTV to guarantee spatial and temporal overlap of the data. Optimizing each of these methods, however, requires conflicting operating conditions: higher temperatures benefit the HTV signals but reduce the available seed density for the PIV through evaporation. Nevertheless, data are found to agree within 10% for the instantaneous velocity profiles and within 5% for the mean profiles and demonstrate the feasibility of HTV for low-speed flows at moderate to high temperatures.

  4. Retrodatazioni di viaggio

    Directory of Open Access Journals (Sweden)

    Mario Piotti

    2013-07-01

    Full Text Available La letteratura di viaggio, in specie quella sette-ottocentesca, presenta, tra molteplici motivi di interesse, ricchi spunti di indagine anche per la storia della lingua e certamente non è il minore quello relativo agli aspetti lessicali. Nell’articolo non si intende dare una descrizione lessicale completa dei testi odeporici esaminati, ma più limitatamente si presenta una serie cospicua di retrodatazioni e datazioni di parole raccolte in quei testi e quindi ricercate, così allargando lo spettro testuale oltre i limiti della letteratura periegetica, attraverso Google libri. Ma nonostante questo parziale spostamento di sguardo, le schede seguenti continuano a documentare la ricchezza del lessico dell’odeporica: termini scientifici, storici, stranierismi e regionalismi ben testimoniano la varia curiosità dei viaggiatori.  Backdating through travelsSeventeenth and eighteenth century travel literature features, among many points of interest, ideas for researching the history of the language, especially lexical aspects. The article does not intend to give a complete lexical description of the odeporic texts examined, but is limited to a substantial number of backdatings and datings of words collected in those texts, thusgoing beyond the limits of textual periegetic literature, through Google books. Despite this partial shift of attention, we continue to document the richness of odeporic vocabulary: scientifically, historically, through foreign terms and regionalisms, bearing witness to the varied curiosity of travelers.

  5. Identificazione, caratterizzazione ed industrializzazione di ceppi di Streptococcus thermophilus per la produzione di yogurt

    OpenAIRE

    D'Alonges, Sara

    2013-01-01

    Il contesto globale del comparto agro-alimentare richiede ad oggi una ricerca continua per assicurare qualità e sicurezza degli alimenti. La produzione moderna di alimenti richiede elevato grado di standardizzazione, particolarmente la produzione gli alimenti fermentati che include un processo biotecnologico in cui la componente biotica gioca un ruolo fondamentale Di qui la necessità disporre di un’ampia gamma di microrganismi atti alla conduzione del processo fermentativo in modo da im...

  6. A new paradigm for particle tracking velocimetry, based on graph-theory and pulsed neural network

    International Nuclear Information System (INIS)

    Derou, D.; Herault, L.

    1994-01-01

    The Particle Tracking Velocimetry (PTV) technique works by recording, at different instances in time, positions of small tracers particles following a flow and illuminated by a sheet, or pseudo sheet, of light. It aims to recognize each particle trajectory, constituted of n different spots and determine thus each particle velocity vector. In this paper, we devise a new method, taking into account a global consistency of the trajectories to be extracted, in terms of visual perception and physical properties. It is based on a graph-theoretic formulation of the particle tracking problem and the use of an original neural network, called pulsed neural network. (authors). 4 figs

  7. Coherent optical transients observed in rubidium atomic line filtered Doppler velocimetry experiments

    Energy Technology Data Exchange (ETDEWEB)

    Fajardo, Mario E., E-mail: mario.fajardo@eglin.af.mil; Molek, Christopher D.; Vesely, Annamaria L. [Air Force Research Laboratory, Munitions Directorate, Ordnance Division, Energetic Materials Branch, AFRL/RWME, 2306 Perimeter Road, Eglin AFB, Florida 32542-5910 (United States)

    2015-10-14

    We report the first successful results from our novel Rubidium Atomic Line Filtered (RALF) Doppler velocimetry apparatus, along with unanticipated oscillatory signals due to coherent optical transients generated within pure Rb vapor cells. RALF is a high-velocity and high-acceleration extension of the well-known Doppler Global Velocimetry (DGV) technique for constructing multi-dimensional flow velocity vector maps in aerodynamics experiments [H. Komine, U.S. Patent No. 4,919,536 (24 April 1990)]. RALF exploits the frequency dependence of pressure-broadened Rb atom optical absorptions in a heated Rb/N{sub 2} gas cell to encode the Doppler shift of reflected near-resonant (λ{sub 0} ≈ 780.24 nm) laser light onto the intensity transmitted by the cell. The present RALF apparatus combines fiber optic and free-space components and was built to determine suitable operating conditions and performance parameters for the Rb/N{sub 2} gas cells. It yields single-spot velocities of thin laser-driven-flyer test surfaces and incorporates a simultaneous Photonic Doppler Velocimetry (PDV) channel [Strand et al., Rev. Sci. Instrum. 77, 083108 (2006)] for validation of the RALF results, which we demonstrate here over the v = 0 to 1 km/s range. Both RALF and DGV presume the vapor cells to be simple Beer's Law optical absorbers, so we were quite surprised to observe oscillatory signals in experiments employing low pressure pure Rb vapor cells. We interpret these oscillations as interference between the Doppler shifted reflected light and the Free Induction Decay (FID) coherent optical transient produced within the pure Rb cells at the original laser frequency; this is confirmed by direct comparison of the PDV and FID signals. We attribute the different behaviors of the Rb/N{sub 2} vs. Rb gas cells to efficient dephasing of the atomic/optical coherences by Rb-N{sub 2} collisions. The minimum necessary N{sub 2} buffer gas density ≈0.3 amagat translates into a

  8. Flow-Tagging Velocimetry for Hypersonic Flows Using Fluorescence of Nitric Oxide

    Science.gov (United States)

    Danehy, P. M.; OByrne, S.; Houwing, A. F. P.

    2001-01-01

    We investigate a new type of flow-tagging velocimetry technique for hypersonic flows. The technique involves exciting a thin line of nitric oxide molecules with a laser beam and then, after some delay, acquiring an image of the displaced line. One component of velocity is determined from the time of flight. This method is applied to measure the velocity profile in a Mach 8.5 laminar, hypersonic boundary layer in the Australian National Universities T2 free-piston shock tunnel. The velocity is measured with an uncertainty of approximately 2%. Comparison with a CFD simulation of the flow shows reasonable agreement.

  9. Spatial filtering velocimetry of objective speckles for measuring out-of-plane motion

    DEFF Research Database (Denmark)

    Jakobsen, Michael Linde; Yura, H. T.; Hanson, Steen Grüner

    2012-01-01

    This paper analyzes the dynamics of objective laser speckles as the distance between the object and the observation plane continuously changes. With the purpose of applying optical spatial filtering velocimetry to the speckle dynamics, in order to measure out-of-plane motion in real time......, a rotational symmetric spatial filter is designed. The spatial filter converts the speckle dynamics into a photocurrent with a quasi-sinusoidal response to the out-of-plane motion. The spatial filter is here emulated with a CCD camera, and is tested on speckles arising from a real application. The analysis...

  10. Surge Flow in a Centrifugal Compressor Measured by Digital Particle Image Velocimetry

    Science.gov (United States)

    Wernet, Mark P.

    2000-01-01

    A planar optical velocity measurement technique known as Particle Image Velocimetry (PIV) is being used to study transient events in compressors. In PIV, a pulsed laser light sheet is used to record the positions of particles entrained in a fluid at two instances in time across a planar region of the flow. Determining the recorded particle displacement between exposures yields an instantaneous velocity vector map across the illuminated plane. Detailed flow mappings obtained using PIV in high-speed rotating turbomachinery components are used to improve the accuracy of computational fluid dynamics (CFD) simulations, which in turn, are used to guide advances in state-of-the-art aircraft engine hardware designs.

  11. New Developments In Particle Image Velocimetry (PIV) For The Study Of Complex Plasmas

    International Nuclear Information System (INIS)

    Thomas, Edward Jr.; Fisher, Ross; Shaw, Joseph; Jefferson, Robert; Cianciosa, Mark; Williams, Jeremiah

    2011-01-01

    Particle Image Velocimetry (PIV) is a fluid measurement technique in which the average displacement of small groups of particles is made by comparing a pair of images that are separated in time by an interval Δt. For over a decade, a several variations of the PIV technique, e.g., two-dimensional, stereoscopic, and tomographic PIV, have been used to characterize particle transport, instabilities, and the thermal properties of complex plasmas. This paper describes the basic principles involved in the PIV analysis technique and discusses potential future applications of PIV to the study of complex plasmas.

  12. Correcting for particle size effects on plasma actuator particle image velocimetry measurements

    Science.gov (United States)

    Masati, A.; Sedwick, R. J.

    2018-01-01

    Particle image velocimetry (PIV) is often used to characterize plasma actuator flow, but particle charging effects are rarely taken into account. A parametric study was conducted to determine the effects of particle size on the velocity results of plasma actuator PIV experiments. Results showed that smaller particles more closely match air flow velocities than larger particles. The measurement uncertainty was quantified by deconvolving the particle image diameter from the correlation diameter. The true air velocity was calculated by linearly extrapolating to the zero-size particle diameter.

  13. Time-resolved Particle Image Velocimetry measurements of the 3D random Richtmyer-Meshkov Instability

    Science.gov (United States)

    Sewell, Everest; Krivets, Vitaliy; Jacobs, Jeffrey

    2017-11-01

    The vertical shock tube at the University of Arizona is used to perform experiments on the multi-mode three-dimensional Richtmyer-Meshkov Instability (RMI). An interface of air and sulfur hexafluoride is formed in a counter flow configuration, and is excited using voice coils to produce faraday-like multi-modal perturbations.This interface is shock accelerated by an approximately Mach 1.2 shockwave to form the RMI. Time resolved Particle Image Velocimetry (PIV) is used to perform analysis of the evolving instability.

  14. cimitero di Praga' di Umberto Eco

    Directory of Open Access Journals (Sweden)

    Maria Grazia Cossu

    2012-12-01

    Full Text Available Examples of Cultural Anti-Semitism in Umberto Eco’s Novel Il cimitero di PragaThe article draws upon Umberto Eco’s recent novel, Il cimitero di Praga, in the consideration of the relationship between narrative fiction and the collective imagination in regards to the genesis and dispersion of The Protocols of the Elders of Zion in the second half of the nineteenth century. A dangerous and mysterious text, The Protocols evoked general clamor and persecutory backlash, as it appeared to document the existence of a Judeo-Masonic conspiracy.In the work, the author also reconstructs sources of the fictional text and traces the historical, political and editorial events surrounding it, plunging into them with a gritty and irreverent realism in a chronicle of the obsession that flowed into the madness of the Shoah.Treating the subject, which is found elsewhere in the scholar’s oeuvre, requires mention of the repertoire of prejudicial accusations against the Jews throughout history, which creates, toward the end of the book, a heated and contentious debate regarding whether such delicate and reckless statements should even be made public at all. This article questions the authorial strategy in Il cimitero di Praga, and considers the novel’s literary agenda, which can be almost interpreted as a call for vigilance against manifestations of anti-Semitism still present in today’s cultural imagination.

  15. Anisotropies in the Diffuse Gamma-Ray Background Measured by the Fermi LAT

    Science.gov (United States)

    2012-05-02

    Particle Physics, The Ohio State University, Columbus, Ohio 43210, USA 4Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa, Italy... Fisica Nucleare, Sezione di Trieste, I-34127 Trieste, Italy 7Dipartimento di Fisica , Università di Trieste, I-34127 Trieste, Italy 8Istituto Nazionale...di Fisica Nucleare, Sezione di Padova, I-35131 Padova, Italy 9Dipartimento di Fisica ‘‘G. Galilei,’’ Università di Padova, I-35131 Padova, Italy

  16. Elementi di interfaccia per l’analisi di strutture murarie

    Directory of Open Access Journals (Sweden)

    Jessica Toti

    2009-04-01

    Full Text Available Il presente articolo riguarda la modellazione del comportamento meccanico di elementi in muratura intesi come sistemi eterogenei composti da malta, blocchi ed interfacce di connessione. La strategiacomputazionale che viene adottata consiste nel modellare separatamente i blocchi, i letti di malta ed le interfacce responsabili di fenomeni di decoesione malta-blocco; a tale scopo, si propone uno speciale modello di interfaccia che combina il danneggiamento con l’attrito. Si sviluppa una procedura numerica, basata sull’algoritmo backward di Eulero, per risolvere il problema evolutivo; per il passo temporale si utilizza invece la tecnica predictor-corrector a controllo di spostamenti. Si effettuano alcune applicazioni numeriche con lo scopodi verificare la capacità del modello e dell’algoritmo proposto nel riprodurre la risposta non lineare della muratura dovuta a fenomeni di degrado localizzati. Infine, si conduce lo studio della modellazione di un arco murario, confrontando i risultati numerici con quelli sperimentali; si dimostra la abilità del modello proposto nel simulare il comportamento globale della struttura ad arco in termini di carico ultimo e di meccanismo di collasso.

  17. Measuring the 3D motion of particles in microchannel acoustophoresis using astigmatism particle tracking velocimetry

    DEFF Research Database (Denmark)

    Augustsson, P.; Barnkob, Rune; Bruus, Henrik

    2012-01-01

    We introduce full three-dimensional tracking of particles in an acoustophoresis microchannel using Astigmatism Particle Tracking Velocimetry (APTV) [1]. For the first time the interaction between acoustic streaming and the primary acoustic radiation force in microchannel acoustophoresis are exami...... relative to the influence from the acoustic radiation force. The current study opens the route to optimized acoustophoretic system design and operation to enable manipulation of small biological components such as spores, bacteria and viruses.......We introduce full three-dimensional tracking of particles in an acoustophoresis microchannel using Astigmatism Particle Tracking Velocimetry (APTV) [1]. For the first time the interaction between acoustic streaming and the primary acoustic radiation force in microchannel acoustophoresis...... are examined in three dimensions. We have quantified the velocity of particles driven by the primary acoustic radiation force and acoustic streaming, respectively, using 0.5-μm and 5-μm particles. Increased ultrasound frequency and lowered viscosity of the medium reduced the influence of acoustic streaming...

  18. Performing particle image velocimetry using artificial neural networks: a proof-of-concept

    Science.gov (United States)

    Rabault, Jean; Kolaas, Jostein; Jensen, Atle

    2017-12-01

    Traditional programs based on feature engineering are underperforming on a steadily increasing number of tasks compared with artificial neural networks (ANNs), in particular for image analysis. Image analysis is widely used in fluid mechanics when performing particle image velocimetry (PIV) and particle tracking velocimetry (PTV), and therefore it is natural to test the ability of ANNs to perform such tasks. We report for the first time the use of convolutional neural networks (CNNs) and fully connected neural networks (FCNNs) for performing end-to-end PIV. Realistic synthetic images are used for training the networks and several synthetic test cases are used to assess the quality of each network’s predictions and compare them with state-of-the-art PIV software. In addition, we present tests on real-world data that prove ANNs can be used not only with synthetic images but also with more noisy, imperfect images obtained in a real experimental setup. While the ANNs we present have slightly higher root mean square error than state-of-the-art cross-correlation methods, they perform better near edges and allow for higher spatial resolution than such methods. In addition, it is likely that one could with further work develop ANNs which perform better that the proof-of-concept we offer.

  19. A multi-time-step noise reduction method for measuring velocity statistics from particle tracking velocimetry

    Science.gov (United States)

    Machicoane, Nathanaël; López-Caballero, Miguel; Bourgoin, Mickael; Aliseda, Alberto; Volk, Romain

    2017-10-01

    We present a method to improve the accuracy of velocity measurements for fluid flow or particles immersed in it, based on a multi-time-step approach that allows for cancellation of noise in the velocity measurements. Improved velocity statistics, a critical element in turbulent flow measurements, can be computed from the combination of the velocity moments computed using standard particle tracking velocimetry (PTV) or particle image velocimetry (PIV) techniques for data sets that have been collected over different values of time intervals between images. This method produces Eulerian velocity fields and Lagrangian velocity statistics with much lower noise levels compared to standard PIV or PTV measurements, without the need of filtering and/or windowing. Particle displacement between two frames is computed for multiple different time-step values between frames in a canonical experiment of homogeneous isotropic turbulence. The second order velocity structure function of the flow is computed with the new method and compared to results from traditional measurement techniques in the literature. Increased accuracy is also demonstrated by comparing the dissipation rate of turbulent kinetic energy measured from this function against previously validated measurements.

  20. Fundamental uncertainty limit of optical flow velocimetry according to Heisenberg's uncertainty principle.

    Science.gov (United States)

    Fischer, Andreas

    2016-11-01

    Optical flow velocity measurements are important for understanding the complex behavior of flows. Although a huge variety of methods exist, they are either based on a Doppler or a time-of-flight measurement principle. Doppler velocimetry evaluates the velocity-dependent frequency shift of light scattered at a moving particle, whereas time-of-flight velocimetry evaluates the traveled distance of a scattering particle per time interval. Regarding the aim of achieving a minimal measurement uncertainty, it is unclear if one principle allows to achieve lower uncertainties or if both principles can achieve equal uncertainties. For this reason, the natural, fundamental uncertainty limit according to Heisenberg's uncertainty principle is derived for Doppler and time-of-flight measurement principles, respectively. The obtained limits of the velocity uncertainty are qualitatively identical showing, e.g., a direct proportionality for the absolute value of the velocity to the power of 32 and an indirect proportionality to the square root of the scattered light power. Hence, both measurement principles have identical potentials regarding the fundamental uncertainty limit due to the quantum mechanical behavior of photons. This fundamental limit can be attained (at least asymptotically) in reality either with Doppler or time-of-flight methods, because the respective Cramér-Rao bounds for dominating photon shot noise, which is modeled as white Poissonian noise, are identical with the conclusions from Heisenberg's uncertainty principle.

  1. Reconstruction of an acoustic pressure field in a resonance tube by particle image velocimetry.

    Science.gov (United States)

    Kuzuu, K; Hasegawa, S

    2015-11-01

    A technique for estimating an acoustic field in a resonance tube is suggested. The estimation of an acoustic field in a resonance tube is important for the development of the thermoacoustic engine, and can be conducted employing two sensors to measure pressure. While this measurement technique is known as the two-sensor method, care needs to be taken with the location of pressure sensors when conducting pressure measurements. In the present study, particle image velocimetry (PIV) is employed instead of a pressure measurement by a sensor, and two-dimensional velocity vector images are extracted as sequential data from only a one- time recording made by a video camera of PIV. The spatial velocity amplitude is obtained from those images, and a pressure distribution is calculated from velocity amplitudes at two points by extending the equations derived for the two-sensor method. By means of this method, problems relating to the locations and calibrations of multiple pressure sensors are avoided. Furthermore, to verify the accuracy of the present method, the experiments are conducted employing the conventional two-sensor method and laser Doppler velocimetry (LDV). Then, results by the proposed method are compared with those obtained with the two-sensor method and LDV.

  2. High Dynamic Velocity Range Particle Image Velocimetry Using Multiple Pulse Separation Imaging

    Directory of Open Access Journals (Sweden)

    Tadhg S. O’Donovan

    2010-12-01

    Full Text Available The dynamic velocity range of particle image velocimetry (PIV is determined by the maximum and minimum resolvable particle displacement. Various techniques have extended the dynamic range, however flows with a wide velocity range (e.g., impinging jets still challenge PIV algorithms. A new technique is presented to increase the dynamic velocity range by over an order of magnitude. The multiple pulse separation (MPS technique (i records series of double-frame exposures with different pulse separations, (ii processes the fields using conventional multi-grid algorithms, and (iii yields a composite velocity field with a locally optimized pulse separation. A robust criterion determines the local optimum pulse separation, accounting for correlation strength and measurement uncertainty. Validation experiments are performed in an impinging jet flow, using laser-Doppler velocimetry as reference measurement. The precision of mean flow and turbulence quantities is significantly improved compared to conventional PIV, due to the increase in dynamic range. In a wide range of applications, MPS PIV is a robust approach to increase the dynamic velocity range without restricting the vector evaluation methods.

  3. High dynamic velocity range particle image velocimetry using multiple pulse separation imaging.

    Science.gov (United States)

    Persoons, Tim; O'Donovan, Tadhg S

    2011-01-01

    The dynamic velocity range of particle image velocimetry (PIV) is determined by the maximum and minimum resolvable particle displacement. Various techniques have extended the dynamic range, however flows with a wide velocity range (e.g., impinging jets) still challenge PIV algorithms. A new technique is presented to increase the dynamic velocity range by over an order of magnitude. The multiple pulse separation (MPS) technique (i) records series of double-frame exposures with different pulse separations, (ii) processes the fields using conventional multi-grid algorithms, and (iii) yields a composite velocity field with a locally optimized pulse separation. A robust criterion determines the local optimum pulse separation, accounting for correlation strength and measurement uncertainty. Validation experiments are performed in an impinging jet flow, using laser-Doppler velocimetry as reference measurement. The precision of mean flow and turbulence quantities is significantly improved compared to conventional PIV, due to the increase in dynamic range. In a wide range of applications, MPS PIV is a robust approach to increase the dynamic velocity range without restricting the vector evaluation methods.

  4. A tracer liquid image velocimetry for multi-layer radial flow in bioreactors.

    Science.gov (United States)

    Gao, Yu-Bao; Liang, Jiu-Xing; Luo, Yu-Xi; Yan, Jia

    2015-02-13

    This paper presents a Tracer Liquid Image Velocimetry (TLIV) for multi-layer radial flow in bioreactors used for cells cultivation of tissue engineering. The goal of this approach is to use simple devices to get good measuring precision, specialized for the case in which the uniform level of fluid shear stress was required while fluid velocity varied smoothly. Compared to the widely used Particles Image Velocimetry (PIV), this method adopted a bit of liquid as tracer, without the need of laser source. Sub-pixel positioning algorithm was used to overcome the adverse effects of the tracer liquid deformation. In addition, a neighborhood smoothing algorithm was used to restrict the measurement perturbation caused by diffusion. Experiments were carried out in a parallel plates flow chamber. And mathematical models of the flow chamber and Computational Fluid Dynamics (CFD) simulation were separately employed to validate the measurement precision of TLIV. The mean relative error between the simulated and measured data can be less than 2%, while in similar validations using PIV, the error was around 8.8%. TLIV avoided the contradiction between the particles' visibility and following performance with tested fluid, which is difficult to overcome in PIV. And TLIV is easier to popularize for its simple experimental condition and low cost.

  5. Introduction to Kinetic Model Equations

    Science.gov (United States)

    2011-01-01

    application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 ∗Dipartimento di Matematica del Politecnico di Milano Piazza Leonardo da Vinci 32...NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Dipartimento di Matematica del Politecnico di Milano Piazza Leonardo da Vinci 32, 20133 Milano

  6. Solving Kinetic Equations on GPU’s

    Science.gov (United States)

    2011-01-01

    7 Acknowledgments 23 8 Appendix: CUDA pseudo-codes 27 ∗Dipartimento di Matematica del Politecnico di Milano Piazza Leonardo da Vinci 32, 20133 Milano...PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Dipartimento di Matematica del Politecnico di Milano Piazza Leonardo da Vinci 32, 20133 Milano, Italy 8

  7. SAW-Based Phononic Crystal Microfluidic Sensor-Microscale Realization of Velocimetry Approaches for Integrated Analytical Platform Applications.

    Science.gov (United States)

    Oseev, Aleksandr; Lucklum, Ralf; Zubtsov, Mikhail; Schmidt, Marc-Peter; Mukhin, Nikolay V; Hirsch, Soeren

    2017-09-23

    The current work demonstrates a novel surface acoustic wave (SAW) based phononic crystal sensor approach that allows the integration of a velocimetry-based sensor concept into single chip integrated solutions, such as Lab-on-a-Chip devices. The introduced sensor platform merges advantages of ultrasonic velocimetry analytic systems and a microacoustic sensor approach. It is based on the analysis of structural resonances in a periodic composite arrangement of microfluidic channels confined within a liquid analyte. Completed theoretical and experimental investigations show the ability to utilize periodic structure localized modes for the detection of volumetric properties of liquids and prove the efficacy of the proposed sensor concept.

  8. L'ISOLA DI ARTURO DI ELSA MORANTE

    African Journals Online (AJOL)

    User

    Vi è una curiosa atmosfera di attesa negli anni '50, ed è questa temperie morale che Elsa Morante rappresenta e interpreta nell'Isola di Arturo. Nel romanzo la Morante ci dà veramente un ritratto intero di quegli anni, nel senso che dal testo sorge una attitudine complessa, contenente in sè la percezione del tempo in corso, ...

  9. Konservatisme Akuntansi di Indonesia

    Directory of Open Access Journals (Sweden)

    Hans Hananto Andreas

    2017-04-01

    Dalam penyajian laporan keuangan yang berkualitas, perusahaan dihadapkan oleh pertimbangan yang salah satunya adalah penerapan konservatisme akuntansi. Penelitian ini bertujuan untuk memberikan bukti empiris pengaruh company growth, profitability, dan investment opportunity set (IOS terhadap penerapan prinsip konservatisme akuntansi. Konservatisme akuntansi dalam penelitian ini diukur menggunakan perhitungan total akrual. Total akrual adalah selisih antara laba sebelum extraordinary item ditambah dengan depresiasi dikurangi dengan arus kas operasi untuk mengetahui apakah perusahaan menggunakan konservatisme akuntansi tinggi atau rendah di dalam perusahaan. Sampel yang digunakan sebanyak 114 perusahaan manufaktur yang terdaftar di Bursa Efek Indonesia (BEI di tahun 2012 dan 2013. Metoda pemilihan sampel yang digunakan yaitu purposive sampling. Alat analisis yang digunakan untuk pengujian adalah regresi linier berganda yang sebelumnya harus lolos uji asumsi klasik. Hasil pengujian secara parsial menunjukkan company growth, profitability dan investment opportunity set berpengaruh positif signifikan terhadap konservatisme akuntansi.

  10. Gli atomi di Boltzmann

    CERN Document Server

    Lindley, David

    2002-01-01

    Ludwig Boltzmann (1844-1906) è il fisico e matematico austriaco che negli ultimi decenni dell'Ottocento e ancora ai primi del Novecento lottò contro l'opinione dominante tra gli scienziati dell'epoca per affermare la teoria atomica della materia. È noto come con Albert Einstein e fino a oggi la fisica si sia sviluppata e abbia celebrato i propri trionfi lungo le linee anticipate da Boltzmann. La controversia con Mach non riguardava soltanto l'esistenza degli atomi, ma l'intero modo di fare fisica che Boltzmann non riteneva di dover limitare allo studio di quantità misurabili, introducendo invece spiegazioni più elaborate basate su ipotesi più ampie.

  11. Sospensione di potestà

    Directory of Open Access Journals (Sweden)

    Maria Fausta Maternini

    2011-03-01

    Full Text Available La voce è destinata alla pubblicazione, in lingua spagnola, nel Diccionario general de Derecho canónico edito dall’Instituto Martìn de Azpilcueta, Universidad de Navarra. SOMMARIO: 1. Il concetto di potestà nella Chiesa – 2. La sospensione di potestà quale atto amministrativo - 3. … in relazione al munus santificandi - 4. … in relazione alla potestà di magistero - 5 … in relazione alla potestà di governo.

  12. Le collezioni di Mammiferi del Museo Civico di Zoologia di Roma: una sintesi storica

    Directory of Open Access Journals (Sweden)

    Gloria Svampa

    2003-10-01

    Full Text Available Il Museo Civico di Zoologia di Roma è sorto nel 1932 all?interno del Giardino Zoologico dell?allora Governatorato di Roma, di cui ha condiviso la direzione tecnica ed amministrativa sino al 1998. Il nucleo centrale delle collezioni è costituito dal materiale di proprietà universitaria, di quello che fu il Museo di Zoologia della Regia Università, a sua volta diretto discendente delle collezioni del Museo di Zoologia ed Anatomia Comparata del Pontificio Archiginnasio Romano. La quasi totalità degli esemplari tassidermizzati risale al periodo in cui l?Istituto di Zoologia fu diretto da Antonio Carruccio (1883-1914. Dal 1932, la collezione teriologica si è andata arricchendo, in particolare di materiale osteologico, soprattutto con acquisizioni provenienti dal Giardino Zoologico e da rare spedizioni scientifiche, come quella organizzata dal CNR nell?Alto Rio Negro del 1962-3, guidata da Ettore Biocca. Anche a causa del fatto che per molti anni il Museo è stato privo di curatori, mancano importanti collezioni teriologiche da studio, fatta eccezione per quella cetologica. In molti casi, singoli esemplari potenzialmente di grande valore scientifico, mancano di dati esatti sulla località di cattura. Nell?ambito di un programma di ricatalogazione della collezione recentemente intrapreso, particolare attenzione è stata posta all?acquisizione di tutti i dati legati alla storia dei singoli esemplari, rintracciabili attraverso i resoconti di viaggio dei singoli esploratori. Nel periodo universitario, infatti, il Museo della nuova capitale d?Italia fu oggetto di grande attenzione da parte di privati ed enti, a partire dai Savoia, che donarono le loro collezioni o il materiale raccolto durante le spedizioni effettuate. Il lavoro di revisione in corso sta mettendo in luce una serie di esemplari meritevoli di ulteriori, dettagliate ricerche. È probabile che molto del materiale del Museo, pervenuto a Roma attraverso donazioni della famiglia reale

  13. Breve Manuale di Geografia Umana

    NARCIS (Netherlands)

    Minca, C.; Colombino, A.

    2012-01-01

    Il percorso per andare al lavoro, la scelta sul dove trascorrere le prossime vacanze, le nostre opinioni sulla politica estera, le nostre preoccupazioni per la crisi economica, le nostre affermazioni di identità, il nostro desiderio di fuga dal quotidiano, perfino la scelta di acquistare una casa in

  14. Peste equina: descrizione di focolai di malattia in Namibia

    Directory of Open Access Journals (Sweden)

    Massimo Scacchia

    2009-06-01

    Full Text Available La peste equina è una malattia virale degli equidi trasmessa da vettori. Scopo di questo lavoro è di riferire su casi di malattia verificatisi in Namibia nel corso degli anni 2006-2008, osservati dal personale dell'Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise “G. Caporale” e del Central Veterinary Laboratory di Windhoek, Namibia e confermati dagli esami di laboratorio. Il lavoro è stato possibile anche grazie alla fattiva collaborazione stabilitasi con i veterinari pubblici, privati e allevatori Namibiani.

  15. I problemi di matematica della Scuola Normale Superiore di Pisa

    CERN Document Server

    Profeti, Alessandro

    1998-01-01

    Nasce come aggiornamento del volume precedente ("I problemi di Matematica della Scuola Normale", 1984) e raccoglie gli esercizi di matematica assegnati all'esame di ammissione alla Scuola Normale Superiore di Pisa dal 1985 al 1997, con la loro risoluzione. Per rendere più efficace lo scopo didattico viene anche presentata una scelta di problemi relativi al periodo precedente (1905-1984). Il libro si rivolge a studenti e docenti della Scuola Secondaria, e si chiude con un Glossario in cui vengono richiamati i termini usati.

  16. Red wine and cardiovascular health the "French Paradox" revisited

    OpenAIRE

    Giuseppe Lippi; Massimo Franchini; Gian Cesare Guidi

    2010-01-01

    Giuseppe Lippi1, Massimo Franchini2, Gian Cesare Guidi31U.O. di Diagnostica Ematochimica, 2Servizio di Immunoematologia e Trasfusione, Dipartimento di Patologia e Medicina di Laboratorio, Azienda Ospedaliero, Universitaria di Parma, Parma, Italy; 3Sezione di Chimica Clinica, Dipartimento di Scienze Morfologico-Biomediche, Università degli Studi di Verona, Verona, ItalyAbstract: The healthful and nutritive properties of wine have been acknowledged for thousands of years, but the obs...

  17. Study of flow around model of cooling tower by means of 2D Particle Image Velocimetry measurement

    Science.gov (United States)

    Barraclough, Veronika; Novotný, Jan; Šafařík, Pavel

    This paper deals with flow around a bluff body of hyperboloid shape. It combines results gathered in the course of research by means of Particle Image Velocimetry (PIV). The experiments were carried out by means of low-frequency 2D PIV and the Reynolds number was 43 000.

  18. Effects of Injection Timing on Fluid Flow Characteristics of Partially Premixed Combustion Based on High-Speed Particle Image Velocimetry

    KAUST Repository

    Izadi Najafabadi, Mohammad; Tanov, Slavey; Wang, Hua; Somers, Bart; Johansson, Bengt; Dam, Nico

    2017-01-01

    behavior. The scope of the present study is to investigate the fluid flow characteristics of PPC at different injection timings. To this end, high-speed Particle Image Velocimetry (PIV) is implemented in a light-duty optical engine to measure fluid flow

  19. Acoustic radiation- and streaming-induced microparticle velocities determined by microparticle image velocimetry in an ultrasound symmetry plane

    DEFF Research Database (Denmark)

    Barnkob, Rune; Augustsson, Per; Laurell, Thomas

    2012-01-01

    We present microparticle image velocimetry measurements of suspended microparticles of diameters from 0.6 to 10μm undergoing acoustophoresis in an ultrasound symmetry plane in a microchannel. The motion of the smallest particles is dominated by the Stokes drag from the induced acoustic streaming...

  20. Selectivity and balance of spatial filtering velocimetry of objective speckles for measuring out-of-plane motion

    DEFF Research Database (Denmark)

    Jakobsen, Michael Linde; Yura, Hal T.; Hanson, Steen Grüner

    2015-01-01

    We probe the dynamics of objective laser speckles as the axial distance between the object and the observation plane changes. With the purpose of measuring out-of-plane motion in real time, we apply optical spatial filtering velocimetry to the speckle dynamics. To achieve this, a rotationally sym...

  1. Study of flow around model of cooling tower by means of 2D Particle Image Velocimetry measurement

    Directory of Open Access Journals (Sweden)

    Barraclough Veronika

    2017-01-01

    Full Text Available This paper deals with flow around a bluff body of hyperboloid shape. It combines results gathered in the course of research by means of Particle Image Velocimetry (PIV. The experiments were carried out by means of low-frequency 2D PIV and the Reynolds number was 43 000.

  2. Applicazione delle linee guida nazionali nell'attivitá di notifica di casi di legionellosi

    Directory of Open Access Journals (Sweden)

    E. Corsano

    2003-05-01

    Full Text Available

    Obiettivi: é noto che effettuare diagnosi di Legionellosi risulta difficile a causa della sovrapposizione della sintomatologia con altre forme di polmonite. Questo spiega, in parte, perché i casi di Legionellosi siano sottostimati. I metodi diagnostici disponibili, sebbene richiedano tempi relativamente lunghi, sono necessari per l’esatta stima di prevalenza della Legionellosi e per gli eventuali interventi preventivi.

    Metodi: nell’Azienda Ospedaliera “G. Panico” di Tricase, seguendo i criteri delle Linee Guida della Legionellosi (G.U. 5 maggio 2000 n. 103 durante la degenza dei pazienti che presentavano segni clinici ed obiettivi di polmonite sono state eseguite indagini radiologiche (Rx Torace, TAC, esami di laboratorio (espettorato, sangue, urina ed avviata terapia antibiotica (macrolidi e cefalosporine di III generazione. L’antigene urinario e le IgG anti-Legionella (metodo IFA, sono stati determinati in collaborazione con il Laboratorio di riferimento Regionale.

    Risultati: nel periodo ottobre 2001 gennaio 2003 sono stati notificati nel nostro ospedale 11 casi di Legionellosi accertati da indagini clinico-strumentali e di laboratorio: tutti i casi avevano titoli anticorpali abbastanza elevati, confermati poi da un secondo controllo a distanza di tempo. Solo due hanno presentato una positività per l’antigene urinario. All’atto della dimissione, per il 63.6% dei casi è stato documentato un miglioramento delle condizioni clinico-laboratoristico-strumentali, nel 18.2% si è avuta una effettiva guarigione. La letalità è stata pari al 18.2%. In tutti casi si è provveduto alla sorveglianza ambientale.

    Considerazioni: i nostri dati evidenziano che i casi di Legionellosi registrati sono stati tutti di tipo comunitario. Una corretta applicazione delle Linee Guida nel sistema di notifica permette l’avvio dell’attività di prevenzione oltre

  3. Determinan Kebahagiaan Di Indonesia

    Directory of Open Access Journals (Sweden)

    Theresia Puji Rahayu

    2016-08-01

      Tujuan penelitian ini adalah untuk menganalisis faktor-faktor penentu kebahagiaan di Indonesia. Dengan menggunakan data antar ruang/silang tempat dari Indonesia Family Life Survey (IFLS wave 4, 2007, studi ini mengambil 17,650 pengamatan yang diestimasi menggunakan model Oprobit. Model Oprobit dipilih karena adanya variabel respon ordinal dan asumsi normal dalam distribusi kesalahan. Hasil penelitian menunjukkan bahwa kebahagiaan di Indonesia secara positif dipengaruhi oleh pendapatan, tingkat pendidikan, status kesehatan yang dirasakan dan modal sosial. Namun demikian, modal sosial yang berkaitan dengan agama dan etnis tidak memiliki pengaruh yang signifikan terhadap kebahagiaan. Semua prediktor bersifat robust. Karakteristik demografi menginformasikan bahwa orang yang menikah, bukan kepala rumah tangga, tinggal di daerah perkotaan, berada di luar pulau Jawa-Bali dan dari suku Jawa lebih bahagia daripada yang lain. Riset ini juga menemukan bahwa tidak terdapat perbedaan dalam tingkat kebahagiaan antara pria dan wanita. Kemudian, hubungan antara kebahagiaan dan usia menunjukkan kurva yang berbentuk U. Terakhir, efek marjinal menunjukkan efek yang berbeda untuk setiap tingkat kebahagiaan karena perubahan unit variabel independen.

  4. DiSC-OPAL

    DEFF Research Database (Denmark)

    Kemal, Mohammed Seifu; Pedersen, Rasmus; Iov, Florin

    2017-01-01

    of such systems. The simulation tool should be able to model Electrical Grid and flexible assets with different time scales and resolution levels fulfilling specific functionalities. In this paper DiSC-OPAL, an OPAL-RT compatible toolbox library for modelling of assets is presented. The library is suitable...

  5. Il Simposio di Platone

    Directory of Open Access Journals (Sweden)

    Maria Chiara Pievatolo

    2013-01-01

    Full Text Available Pensate che i testi antichi siano semplicemente vecchi? Che l’amore platonico non vada mai  al sodo? Leggere il Simposio di Platone confrontandosi direttamente col testo, com’è possibile fare grazie al Perseus Project, vi farà cambiare idea.

  6. Akademi Golf di Surabaya

    OpenAIRE

    Santoso, Indra Purnama

    2013-01-01

    Golf adalah salah satu olahraga yang mulaipopular pada tahun-tahun ini. Popularitasnya makinmeningkat yang berdampak pada meningkatnya jumlahpemain golf padahal fasilitas yang mewadahinya sangatminim. Dalam Perancangan Akademi Golf di Surabaya,diharapkan dapat menambah fasilitas khususnya dalambidang pendidikan mengingat penggunanya mulaibanyak pada kaum muda. Fasilitas-fasilitas yangdirencanakan secara keseluruhan berhubungan denganpendidikan golf dimana juga mempertahankan kondisieksisting ...

  7. Estimation of the measurement uncertainty in magnetic resonance velocimetry based on statistical models

    Energy Technology Data Exchange (ETDEWEB)

    Bruschewski, Martin; Schiffer, Heinz-Peter [Technische Universitaet Darmstadt, Institute of Gas Turbines and Aerospace Propulsion, Darmstadt (Germany); Freudenhammer, Daniel [Technische Universitaet Darmstadt, Institute of Fluid Mechanics and Aerodynamics, Center of Smart Interfaces, Darmstadt (Germany); Buchenberg, Waltraud B. [University Medical Center Freiburg, Medical Physics, Department of Radiology, Freiburg (Germany); Grundmann, Sven [University of Rostock, Institute of Fluid Mechanics, Rostock (Germany)

    2016-05-15

    Velocity measurements with magnetic resonance velocimetry offer outstanding possibilities for experimental fluid mechanics. The purpose of this study was to provide practical guidelines for the estimation of the measurement uncertainty in such experiments. Based on various test cases, it is shown that the uncertainty estimate can vary substantially depending on how the uncertainty is obtained. The conventional approach to estimate the uncertainty from the noise in the artifact-free background can lead to wrong results. A deviation of up to -75% is observed with the presented experiments. In addition, a similarly high deviation is demonstrated with the data from other studies. As a more accurate approach, the uncertainty is estimated directly from the image region with the flow sample. Two possible estimation methods are presented. (orig.)

  8. Estimation of the measurement uncertainty in magnetic resonance velocimetry based on statistical models

    Science.gov (United States)

    Bruschewski, Martin; Freudenhammer, Daniel; Buchenberg, Waltraud B.; Schiffer, Heinz-Peter; Grundmann, Sven

    2016-05-01

    Velocity measurements with magnetic resonance velocimetry offer outstanding possibilities for experimental fluid mechanics. The purpose of this study was to provide practical guidelines for the estimation of the measurement uncertainty in such experiments. Based on various test cases, it is shown that the uncertainty estimate can vary substantially depending on how the uncertainty is obtained. The conventional approach to estimate the uncertainty from the noise in the artifact-free background can lead to wrong results. A deviation of up to -75 % is observed with the presented experiments. In addition, a similarly high deviation is demonstrated with the data from other studies. As a more accurate approach, the uncertainty is estimated directly from the image region with the flow sample. Two possible estimation methods are presented.

  9. Stereoscopic particle image velocimetry investigations of the mixed convection exchange flow through a horizontal vent

    Science.gov (United States)

    Varrall, Kevin; Pretrel, Hugues; Vaux, Samuel; Vauquelin, Olivier

    2017-10-01

    The exchange flow through a horizontal vent linking two compartments (one above the other) is studied experimentally. This exchange is here governed by both the buoyant natural effect due to the temperature difference of the fluids in both compartments, and the effect of a (forced) mechanical ventilation applied in the lower compartment. Such a configuration leads to uni- or bi-directional flows through the vent. In the experiments, buoyancy is induced in the lower compartment thanks to an electrical resistor. The forced ventilation is applied in exhaust or supply modes and three different values of the vent area. To estimate both velocity fields and flow rates at the vent, measurements are realized at thermal steady state, flush the vent in the upper compartment using stereoscopic particle image velocimetry (SPIV), which is original for this kind of flow. The SPIV measurements allows the area occupied by both upward and downward flows to be determined.

  10. PIV-DCNN: cascaded deep convolutional neural networks for particle image velocimetry

    Science.gov (United States)

    Lee, Yong; Yang, Hua; Yin, Zhouping

    2017-12-01

    Velocity estimation (extracting the displacement vector information) from the particle image pairs is of critical importance for particle image velocimetry. This problem is mostly transformed into finding the sub-pixel peak in a correlation map. To address the original displacement extraction problem, we propose a different evaluation scheme (PIV-DCNN) with four-level regression deep convolutional neural networks. At each level, the networks are trained to predict a vector from two input image patches. The low-level network is skilled at large displacement estimation and the high- level networks are devoted to improving the accuracy. Outlier replacement and symmetric window offset operation glue the well- functioning networks in a cascaded manner. Through comparison with the standard PIV methods (one-pass cross-correlation method, three-pass window deformation), the practicability of the proposed PIV-DCNN is verified by the application to a diversity of synthetic and experimental PIV images.

  11. Capillary red blood cell velocimetry by phase-resolved optical coherence tomography.

    Science.gov (United States)

    Tang, Jianbo; Erdener, Sefik Evren; Fu, Buyin; Boas, David A

    2017-10-01

    We present a phase-resolved optical coherence tomography (OCT) method to extend Doppler OCT for the accurate measurement of the red blood cell (RBC) velocity in cerebral capillaries. OCT data were acquired with an M-mode scanning strategy (repeated A-scans) to account for the single-file passage of RBCs in a capillary, which were then high-pass filtered to remove the stationary component of the signal to ensure an accurate measurement of phase shift of flowing RBCs. The angular frequency of the signal from flowing RBCs was then quantified from the dynamic component of the signal and used to calculate the axial speed of flowing RBCs in capillaries. We validated our measurement by RBC passage velocimetry using the signal magnitude of the same OCT time series data.

  12. Velocity Field Measurements of Human Coughing Using Time Resolved Particle Image Velocimetry

    Science.gov (United States)

    Khan, T.; Marr, D. R.; Higuchi, H.; Glauser, M. N.

    2003-11-01

    Quantitative fluid mechanics analysis of human coughing has been carried out using new Time Resolved Particle Image Velocimetry (TRPIV). The study involves measurement of velocity vector time-histories and velocity profiles. It is focused on the average normal human coughing. Some work in the past on cough mechanics has involved measurement of flow rates, tidal volumes and sub-glottis pressure. However, data of unsteady velocity vector field of the exiting highly time-dependent jets is not available. In this study, human cough waveform data are first acquired in vivo using conventional respiratory instrumentation for various volunteers of different gender/age groups. The representative waveform is then reproduced with a coughing/breathing simulator (with or without a manikin) for TRPIV measurements and analysis. The results of this study would be useful not only for designing of indoor air quality and heating, ventilation and air conditioning systems, but also for devising means of protection against infectious diseases.

  13. Spatial filtering velocimetry revisited: exact short-time detecting schemes from arbitrarily small-size reticles

    International Nuclear Information System (INIS)

    Ando, S; Nara, T; Kurihara, T

    2014-01-01

    Spatial filtering velocimetry was proposed in 1963 by Ator as a velocity-sensing technique for aerial camera-control systems. The total intensity of a moving surface is observed through a set of parallel-slit reticles, resulting in a narrow-band temporal signal whose frequency is directly proportional to the image velocity. However, even despite its historical importance and inherent technical advantages, the mathematical formulation of this technique is only valid when infinite-length observation in both space and time is possible, which causes significant errors in most applications where a small receptive window and high resolution in both axes are desired. In this study, we apply a novel mathematical technique, the weighted integral method, to solve this problem, and obtain exact sensing schemes and algorithms for finite (arbitrarily small but non-zero) size reticles and short-time estimation. Practical considerations for utilizing these schemes are also explored both theoretically and experimentally. (paper)

  14. Correcting for color crosstalk and chromatic aberration in multicolor particle shadow velocimetry

    International Nuclear Information System (INIS)

    McPhail, M J; Fontaine, A A; Krane, M H; Goss, L; Crafton, J

    2015-01-01

    Color crosstalk and chromatic aberration can bias estimates of fluid velocity measured by color particle shadow velocimetry (CPSV), using multicolor illumination and a color camera. This article describes corrections to remove these bias errors, and their evaluation. Color crosstalk removal is demonstrated with linear unmixing. It is also shown that chromatic aberrations may be removed using either scale calibration, or by processing an image illuminated by all colors simultaneously. CPSV measurements of a fully developed turbulent pipe flow of glycerin were conducted. Corrected velocity statistics from these measurements were compared to both single-color PSV and LDV measurements and showed excellent agreement to fourth-order, to well into the viscous sublayer. Recommendations for practical assessment and correction of color aberration and color crosstalk are discussed. (paper)

  15. Investigating fundamental properties of wind turbine wake structure using particle image velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Whale, J. [Univ. of Edinburgh, Dept. of Mechanical Engineering, Edinburgh (United Kingdom)

    1997-08-01

    Low Reynolds number flow visualization tests are often used for showing the flow pattern changes associated with changes in lift-coefficients at a higher Reynolds number. In wind turbine studies, analysis of measured wake structures at small scale may reveal fundamental properties of the wake which will offer wake modellers a more complete understanding of rotor flows. Measurements are presented from experiments on a model wind turbine rig conducted in a water channel. The laser-optics technique of Particle Image Velocimetry (PIV) is used to make simultaneous multi-point measurements of the wake flow behind small-scale rotors. Analysis of the PIV data shows trends in velocity and vorticity structure in the wake. Study of the flow close to the rotor plane reveals information on stalled flow and blade performance. (au)

  16. Study of fish response using particle image velocimetry and high-speed, high-resolution imaging

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Z. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Richmond, M. C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mueller, R. P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gruensch, G. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2004-10-01

    Fish swimming has fascinated both engineers and fish biologists for decades. Digital particle image velocimetry (DPIV) and high-speed, high-resolution digital imaging are recently developed analysis tools that can help engineers and biologists better understand how fish respond to turbulent environments. This report details studies to evaluate DPIV. The studies included a review of existing literature on DPIV, preliminary studies to test the feasibility of using DPIV conducted at our Flow Biology Laboratory in Richland, Washington September through December 2003, and applications of high-speed, high-resolution digital imaging with advanced motion analysis to investigations of fish injury mechanisms in turbulent shear flows and bead trajectories in laboratory physical models. Several conclusions were drawn based on these studies, which are summarized as recommendations for proposed research at the end of this report.

  17. Speckle and fringe dynamics in imagingspeckle-pattern interferometry for spatial-filtering velocimetry

    DEFF Research Database (Denmark)

    Jakobsen, Michael Linde; Iversen, Theis F. Q.; Yura, Harold T.

    2011-01-01

    This paper analyzes the dynamics of laser speckles and fringes, formed in an imaging-speckle-pattern interferometer with the purpose of sensing linear three-dimensional motion and out-of-plane components of rotation in real time, using optical spatial-filtering-velocimetry techniques. The ensemble......-average definition of the cross-correlation function is applied to the intensity distributions, obtained in the observation plane at two positions of the object. The theoretical analysis provides a description for the dynamics of both the speckles and the fringes. The analysis reveals that both the magnitude...... and direction of all three linear displacement components of the object movement can be determined. Simultaneously, out-ofplane rotation of the object including the corresponding directions can be determined from the spatial gradient of the in-plane fringe motion throughout the observation plane. The theory...

  18. Shock Initiation of Wedge-shaped Explosive Measured with Smear Camera and Photon Doppler Velocimetry

    Science.gov (United States)

    Gu, Yan

    2017-06-01

    Triaminotrinitrobenzene (TATB) is an important insensitive high explosive in conventional weapons due to its safety and high energy. In order to have an insight into the shock initiation performance of a TATB-based insensitive high explosive (IHE), experimental measurements of the particle velocity histories of the TATB-based Explosive using Photon Doppler Velocimetry and shock wave profile of the TATB-based explosive using High Speed Rotating Mirror Smear Camera had been performed. In this paper, we would describe the shock initiation performance of the TATB-based explosive by run-to-detonation distance and the particle velocity history at an initialization shock of about 7.9 GPa. The parameters of hugoniot of unreacted the TATB-based explosive and Pop relationship could be derived with the particle velocity history obtained in this paper.

  19. X-ray doppler velocimetry for diagnosis of fluid motion in ICF implosions

    Science.gov (United States)

    Koch, J. A.; King, J. A.; Huffman, E.; Freeman, R. R.; Dutra, E. C.; Field, J. E.; Kilkenny, J. D.; Hall, G. N.; Harding, E.; Rochau, G. A.; Porter, J. L.; Covington, A. M.; Beg, F. N.

    2017-08-01

    We are developing a novel diagnostic for measurement of bulk fluid motion in materials, that is particularly applicable to very hot, x-ray emitting plasmas in the High Energy Density Physics (HEDP) regime. The X-ray Doppler Velocimetry (XDV) technique relies on monochromatic imaging in multiple x-ray energy bands near the center of an x-ray emission line in a plasma, and utilizes bent imaging crystals. Higher energy bands are preferentially sensitive to plasma moving towards the viewer, while lower energy bands are preferentially sensitive to plasma moving away from the viewer. Combining multiple images in different energy bands allows for a reconstruction of the fluid velocity field integrated along the line of sight. We review the technique, and we discuss progress towards benchmarking the technique with proof-of-principle HEDP experiments.

  20. Spatial filtering velocimetry for real-time out-of-plane displacement measurements

    DEFF Research Database (Denmark)

    Olesen, Anders Sig; Yura, H.T.; Jakobsen, Michael Linde

    2016-01-01

    power spectrum of the photocurrent produced by this filter. This main contribution of this paper is a model, which describe the selectivity of the sensor, applied to speckle dynamics generated by an object moving out-of-plane. To motivate our interest in these filters we also present an all optical......We probe the dynamics of objective laser speckles as the axial distance between the object and the observation plane changes. With the purpose of measuring out-of-plane motion in real time, we apply optical spatial filtering velocimetry to the speckle dynamics. To achieve this, a rotationally...... symmetric spatial filter is designed. The spatial filter converts the speckle dynamics into a photocurrent with a quasi-sinusoidal response to the out-of-plane motion. The selectivity of the sensor relates directly to the uncertainty on sensor measurements. The selectivity most be derived from a temporal...

  1. Spectroscopic interpretation and velocimetry analysis of fluctuations in a cylindrical plasma recorded by a fast camera

    Science.gov (United States)

    Oldenbürger, S.; Brandt, C.; Brochard, F.; Lemoine, N.; Bonhomme, G.

    2010-06-01

    Fast visible imaging is used on a cylindrical magnetized argon plasma produced by thermionic discharge in the Mirabelle device. To link the information collected with the camera to a physical quantity, fast camera movies of plasma structures are compared to Langmuir probe measurements. High correlation is found between light fluctuations and plasma density fluctuations. Contributions from neutral argon and ionized argon to the overall light intensity are separated by using interference filters and a light intensifier. Light emitting transitions are shown to involve a metastable neutral argon state that can be excited by thermal plasma electrons, thus explaining the good correlation between light and density fluctuations. The propagation velocity of plasma structures is calculated by adapting velocimetry methods to the fast camera movies. The resulting estimates of instantaneous propagation velocity are in agreement with former experiments. The computation of mean velocities is discussed.

  2. Spectroscopic interpretation and velocimetry analysis of fluctuations in a cylindrical plasma recorded by a fast camera

    International Nuclear Information System (INIS)

    Oldenbuerger, S.; Brandt, C.; Brochard, F.; Lemoine, N.; Bonhomme, G.

    2010-01-01

    Fast visible imaging is used on a cylindrical magnetized argon plasma produced by thermionic discharge in the Mirabelle device. To link the information collected with the camera to a physical quantity, fast camera movies of plasma structures are compared to Langmuir probe measurements. High correlation is found between light fluctuations and plasma density fluctuations. Contributions from neutral argon and ionized argon to the overall light intensity are separated by using interference filters and a light intensifier. Light emitting transitions are shown to involve a metastable neutral argon state that can be excited by thermal plasma electrons, thus explaining the good correlation between light and density fluctuations. The propagation velocity of plasma structures is calculated by adapting velocimetry methods to the fast camera movies. The resulting estimates of instantaneous propagation velocity are in agreement with former experiments. The computation of mean velocities is discussed.

  3. Two-phase velocity measurements around cylinders using particle image velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Y.A.; Philip, O.G.; Schmidl, W.D. [Texas A& M Univ., College Station, TX (United States)] [and others

    1995-09-01

    The particle Image Velocimetry flow measurement technique was used to study both single-phase flow and two-phase flow across a cylindrical rod inserted in a channel. First, a flow consisting of only a single-phase fluid was studied. The experiment consisted of running a laminar flow over four rods inserted in a channel. The water flow rate was 126 cm{sup 3}/s. Then a two-phase flow was studied. A mixture of water and small air bubbles was used. The water flow rate was 378 cm{sup 3}/s and the air flow rate was approximately 30 cm{sup 3}/s. The data are analyzed to obtain the velocity fields for both experiments. After interpretation of the velocity data, forces acting on a bubble entrained by the vortex were calculated successfully. The lift and drag coefficients were calculated using the velocity measurements and the force data.

  4. Particle image velocimetry investigation of flow over unsteady airfoil with trailing-edge strip

    Energy Technology Data Exchange (ETDEWEB)

    Gerontakos, P.; Lee, T. [McGill University, Montreal, QC (Canada)

    2008-04-15

    The flow over a flapped NACA 0012 airfoil, oscillated slightly through the static-stall angle, was investigated by using particle image velocimetry, and was supplemented by surface pressure and dynamic-load measurements. A significant increase in the dynamic lift force and nose-down pitching moment was observed. The most pronounced flow phenomenon was the formation and detachment of an energetic leading-edge vortex compared to the no-flapped airfoil. The details of the underlying physical mechanisms responsible for the various light-stall flow processes were provided via the instantaneous velocity and vorticity fields measurements. In contrast to the Gurney flap, the inverted trailing-edge strip led to an improved negative damping while a reduced lift force. The addition of an inverted strip always led to the appearance of a Karman-type vortex shedding street immediately downstream of the strip over the entire oscillation cycle. (orig.)

  5. Rainbow Particle Imaging Velocimetry for Dense 3D Fluid Velocity Imaging

    KAUST Repository

    Xiong, Jinhui

    2017-04-11

    Despite significant recent progress, dense, time-resolved imaging of complex, non-stationary 3D flow velocities remains an elusive goal. In this work we tackle this problem by extending an established 2D method, Particle Imaging Velocimetry, to three dimensions by encoding depth into color. The encoding is achieved by illuminating the flow volume with a continuum of light planes (a “rainbow”), such that each depth corresponds to a specific wavelength of light. A diffractive component in the camera optics ensures that all planes are in focus simultaneously. For reconstruction, we derive an image formation model for recovering stationary 3D particle positions. 3D velocity estimation is achieved with a variant of 3D optical flow that accounts for both physical constraints as well as the rainbow image formation model. We evaluate our method with both simulations and an experimental prototype setup.

  6. Particle Data Management Software for 3DParticle Tracking Velocimetry and Related Applications – The Flowtracks Package

    Directory of Open Access Journals (Sweden)

    Yosef Meller

    2016-06-01

    Full Text Available The Particle Tracking Velocimetry (PTV community employs several formats of particle information such as position and velocity as function of time, i.e. trajectory data, as a result of diverging needs unmet by existing formats, and a number of different, mostly home-grown, codes for handling the data. Flowtracks is a Python package that provides a single code base for accessing different formats as a database, i.e. storing data and programmatically manipulating them using format-agnostic data structures. Furthermore, it offers an HDF5-based format that is fast and extensible, obviating the need for other formats. The package may be obtained from https://github.com/OpenPTV/postptv and used as-is by many fluid-dynamics labs, or with minor extensions adhering to a common interface, by researchers from other fields, such as biology and population tracking.

  7. Particle image and acoustic Doppler velocimetry analysis of a cross-flow turbine wake

    Science.gov (United States)

    Strom, Benjamin; Brunton, Steven; Polagye, Brian

    2017-11-01

    Cross-flow turbines have advantageous properties for converting kinetic energy in wind and water currents to rotational mechanical energy and subsequently electrical power. A thorough understanding of cross-flow turbine wakes aids understanding of rotor flow physics, assists geometric array design, and informs control strategies for individual turbines in arrays. In this work, the wake physics of a scale model cross-flow turbine are investigated experimentally. Three-component velocity measurements are taken downstream of a two-bladed turbine in a recirculating water channel. Time-resolved stereoscopic particle image and acoustic Doppler velocimetry are compared for planes normal to and distributed along the turbine rotational axis. Wake features are described using proper orthogonal decomposition, dynamic mode decomposition, and the finite-time Lyapunov exponent. Consequences for downstream turbine placement are discussed in conjunction with two-turbine array experiments.

  8. Functionalised alginate flow seeding microparticles for use in Particle Image Velocimetry (PIV).

    Science.gov (United States)

    Varela, Sylvana; Balagué, Isaac; Sancho, Irene; Ertürk, Nihal; Ferrando, Montserrat; Vernet, Anton

    2016-01-01

    Alginate microparticles as flow seeding fulfil all the requirements that are recommended for the velocity measurements in Particle Image Velocimetry (PIV). These spherical microparticles offer the advantage of being environmentally friendly, having excellent seeding properties and they can be produced via a very simple process. In the present study, the performances of alginate microparticles functionalised with a fluorescent dye, Rhodamine B (RhB), for PIV have been studied. The efficacy of fluorescence is appreciated in a number of PIV applications since it can boost the signal-to-noise ratio. Alginate microparticles functionalised with RhB have high emission efficiency, desirable match with fluid density and controlled size. The study of the particles behaviour in strong acid and basic solutions and ammonia is also included. This type of particles can be used for measurements with PIV and Planar Laser Induced Fluorescence (PLIF) simultaneously, including acid-base reactions.

  9. Acceleration Characteristics of a Rock Slide Using the Particle Image Velocimetry Technique

    Directory of Open Access Journals (Sweden)

    Guoqing Chen

    2016-01-01

    Full Text Available The Particle Image Velocimetry (PIV technique with high precision and spatial resolution is a suitable sensor for flow field experiments. In this paper, the PIV technology was used to monitor the development of a displacement field, velocity field and acceleration field of a rock slide. It was found that the peak acceleration of the sliding surface appeared earlier than the peak acceleration of the sliding body. The characteristics of the rock slide including the short failure time, high velocities, and large accelerations indicate that the sliding forces and energy release rate of the slope are high. The deformation field showed that the sliding body was sliding outwards along the sliding surface while the sliding bed moved in an opposite direction. Moving upwards at the top of the sliding bed can be one of the warning signs for rock slide failure.

  10. Measurement of fluid velocity development behind a circular cylinder using particle image velocimetry (PIV)

    International Nuclear Information System (INIS)

    Goharzadeh, Afshin; Molki, Arman

    2015-01-01

    In this paper we present a non-intrusive experimental approach for obtaining a two-dimensional velocity distribution around a 22 mm diameter circular cylinder mounted in a water tunnel. Measurements were performed for a constant Reynolds number of 7670 using a commercial standard particle image velocimetry (PIV) system. Different flow patterns generated behind the circular cylinder are discussed. Both instantaneous and time-averaged velocity distributions with corresponding streamlines are obtained. Key concepts in fluid mechanics, such as contra-rotating vortices, von Kármán vortex street, and laminar-turbulent flow, are discussed. In addition, brief historical information pertaining to the development of flow measurement techniques—in particular, PIV—is described. (paper)

  11. High resolution measurement of the velocity profiles of channel flows using the particle image velocimetry technique

    International Nuclear Information System (INIS)

    Nor Azizi Mohamed

    2000-01-01

    The high resolution velocity profiles of a uniform steady channel flow and a flow beneath waves were obtained using the particle image velocimetry (PIV) technique. The velocity profiles for each flow were calculated for both components. It is shown that the profiles obtained are very precise, displaying the point velocities from a few millimeters from the bottom of the channel up to the water surface across the water depth. In the case of the wave-induced flow, the profiles are shown under the respective wave phases and given in a plane representation. High resolution measurement of point velocities in a flow is achievable using PIV and invaluable when applied to a complex flow. (Author)

  12. Application of FLEET Velocimetry in the NASA Langley 0.3-meter Transonic Cryogenic Tunnel

    Science.gov (United States)

    Burns, Ross A.; Danehy, Paul M.; Halls, Benjamin R.; Jiang, Naibo

    2015-01-01

    Femtosecond laser electronic excitation and tagging (FLEET) velocimetry is demonstrated in a large-scale transonic cryogenic wind tunnel. Test conditions include total pressures, total temperatures, and Mach numbers ranging from 15 to 58 psia, 200 to 295 K, and 0.2 to 0.75, respectively. Freestream velocity measurements exhibit accuracies within 1 percent and precisions better than 1 m/s. The measured velocities adhere closely to isentropic flow theory over the domain of temperatures and pressures that were tested. Additional velocity measurements are made within the tunnel boundary layer; virtual trajectories traced out by the FLEET signal are indicative of the characteristic turbulent behavior in this region of the flow, where the unsteadiness increases demonstrably as the wall is approached. Mean velocities taken within the boundary layer are in agreement with theoretical velocity profiles, though the fluctuating velocities exhibit a greater deviation from theoretical predictions.

  13. Shifted knife-edge aperture digital in-line holography for fluid velocimetry.

    Science.gov (United States)

    Palero, Virginia; Lobera, Julia; Andrés, Nieves; Arroyo, M Pilar

    2014-06-01

    We describe a digital holography technique that, with the simplicity of an in-line configuration, produces holograms where the real and virtual images are completely separated, as in an off-axis configuration. An in-line setup, in which the object is imaged near the sensor, is modified by placing a shifted knife-edge aperture that blocks half the frequency spectrum at the focal plane of the imaging lens. This simple modification of the in-line holographic configuration allows discriminating the virtual and real images. As a fluid velocimetry technique, the use of this aperture removes the minimum defocusing distance requisite and reduces the out-of-plane velocity measurement errors of classical in-line holography. Results with different test objects are shown.

  14. Particle image velocimetry measurements of 2-dimensional velocity field around twisted tape

    Energy Technology Data Exchange (ETDEWEB)

    Song, Min Seop; Park, So Hyun; Kim, Eung Soo, E-mail: kes7741@snu.ac.kr

    2016-11-01

    Highlights: • Measurements of the flow field in a pipe with twisted tape were conducted by particle image velocimetry (PIV). • A novel matching index of refraction technique utilizing 3D printing and oil mixture was adopted to make the test section transparent. • Undistorted particle images were clearly captured in the presence of twisted tape. • 2D flow field in the pipe with twisted tape revealed the characteristic two-peak velocity profile. - Abstract: Twisted tape is a passive component used to enhance heat exchange in various devices. It induces swirl flow that increases the mixing of fluid. Thus, ITER selected the twisted tape as one of the candidates for turbulence promoting in the divertor cooling. Previous study was mainly focused on the thermohydraulic performance of the twisted tape. As detailed data on the velocity field around the twisted tape was insufficient, flow visualization study was performed to provide fundamental data on velocity field. To visualize the flow in a complex structure, novel matching index of refraction technique was used with 3-D printing and mixture of anise and mineral oil. This technique enables the camera to capture undistorted particle image for velocity field measurement. Velocity fields at Reynolds number 1370–9591 for 3 different measurement plane were obtained through particle image velocimetry. The 2-dimensional averaged velocity field data were obtained from 177 pair of instantaneous velocity fields. It reveals the characteristic two-peak flow motion in axial direction. In addition, the normalized velocity profiles were converged with increase of Reynolds numbers. Finally, the uncertainty of the result data was analyzed.

  15. Particle image velocimetry measurements of Mach 3 turbulent boundary layers at low Reynolds numbers

    Science.gov (United States)

    Brooks, J. M.; Gupta, A. K.; Smith, M. S.; Marineau, E. C.

    2018-05-01

    Particle image velocimetry (PIV) measurements of Mach 3 turbulent boundary layers (TBL) have been performed under low Reynolds number conditions, Re_τ =200{-}1000, typical of direct numerical simulations (DNS). Three reservoir pressures and three measurement locations create an overlap in parameter space at one research facility. This allows us to assess the effects of Reynolds number, particle response and boundary layer thickness separate from facility specific experimental apparatus or methods. The Morkovin-scaled streamwise fluctuating velocity profiles agree well with published experimental and numerical data and show a small standard deviation among the nine test conditions. The wall-normal fluctuating velocity profiles show larger variations which appears to be due to particle lag. Prior to the current study, no detailed experimental study characterizing the effect of Stokes number on attenuating wall-normal fluctuating velocities has been performed. A linear variation is found between the Stokes number ( St) and the relative error in wall-normal fluctuating velocity magnitude (compared to hot wire anemometry data from Klebanoff, Characteristics of Turbulence in a Boundary Layer with Zero Pressure Gradient. Tech. Rep. NACA-TR-1247, National Advisory Committee for Aeronautics, Springfield, Virginia, 1955). The relative error ranges from about 10% for St=0.26 to over 50% for St=1.06. Particle lag and spatial resolution are shown to act as low-pass filters on the fluctuating velocity power spectral densities which limit the measurable energy content. The wall-normal component appears more susceptible to these effects due to the flatter spectrum profile which indicates that there is additional energy at higher wave numbers not measured by PIV. The upstream inclination and spatial correlation extent of coherent turbulent structures agree well with published data including those using krypton tagging velocimetry (KTV) performed at the same facility.

  16. Il concetto di Natura nella filosofia di Denis Diderot

    Directory of Open Access Journals (Sweden)

    Francesco Consiglio

    2014-03-01

    Full Text Available L’immagine della Natura che emerge dalla lettura delle opere di Diderot, è quella di una sorta di organismo in cui tutto risulta legato da una rete di forze inquadrate in un ordine omogeneo e dinamico. Le leggi di quest’ordine sono riscontrabili in tutti gli eventi naturali ed ogni fenomeno non è mai frutto del caso, ma ordinato deterministicamente. Allo spinozismo di quest’ordine geometrico si coniuga un atomismo di matrice epicurea, speci camente nella versione lucreziana del De Rerum Natura: gli atomi che costituiscono la materia si combinano da sempre e all’in nito in un continuo divenire di forme normate da leggi intrinseche, e gli individui nascono dal cozzare e dall’ammassarsi di questi atomi. Non esiste uno stadio culmine di questa “evoluzione”, piuttosto esistono in nite varianti, nel tempo e nello spazio, di un unico modello prototipico che, secondo Diderot, evolve in una specie o in un'altra in maniera totalmente a- nalistica, sebbene assolutamente determinis- tica. La regolarità dell’ordine (per no nell’apparente caos di un turbine di pol- vere e il continuo farsi e rifarsi delle forme si connettono al principio di conti- nuità della natura: la natura non fa salti, tutto è connesso come in una ragnatela e la materia continua muta la sua disposizione in grumi di atomi che, secondo il principio dell’epigenesi, giungono a formare gli individui. Le opere in cui Diderot elabora in maniera più organica e precisa la sua concezione della natura sono particolarmente due: L’interpretazione della natura (1753 e Il sogno di d’Alembert (1769. In mezzo a queste stanno gli scritti sui Sa- lons, tra i quali è particolarmente saliente, per il discorso sulla natura, quello del 1767, in cui, con la Promenade Vernet, molti di questi temi vengono a rontati o ripresi nel pittoricismo della narrazione, attraverso limpide metafore. Natura e arte, in Diderot, sono strettamente connesse. La seconda imita la prima, ma non tenta

  17. Integrazione rigorosa di dati provenienti da fonti di acquisizione differenti

    Directory of Open Access Journals (Sweden)

    Leandro Bornaz

    2011-04-01

    Full Text Available La geomatica mette oggi a disposizione di esperti di diverse discipline un’ampia gamma di strumenti e tecniche che vengono utilizzate estensivamente come sostegno per l’acquisizione, la contestualizzazione e la georeferenziazione di informazioni molto diversificate come ad esempio dati georadar, geosismici, interferometrici, provenienti da strumenti di misura spesso utilizzati in diversi ambiti e con sistemi di riferimento differenti, talvolta non direttamente compatibili tra loro. Questa problematica, spesso trascurata utilizzando un approccio di tipo classico, è stata affrontata e risolta in modo rigoroso dagli autori permettendo così l’integrazione corretta di dati di differente natura e provenienza.Integration of data acquired from different sourcesGeomatics today offers to experts from different disciplines a wide range of tools and techniques, which are used extensively as technical support for the acquisition, context and geo-refer-encing data coming from different investigations: geo radar, interpherometry, geophysics analysis. Each technology gener-ally provide data with different reference systems, often not di-rectly compatible each other. This problem, often overlooked by using a classical approach, has been resolved in a rigorous way by the authors thus allowing proper integration of data of different nature.

  18. ANTROPOLOGIA DI UN INTELLETTUALE, GIUSEPPE CASSIERI

    African Journals Online (AJOL)

    Di conseguenza la mancata possibilità di esprimersi, di esistere, di vivere si ripercuote nell'assenza di sogni, a discapito di una attività e creatività mentale che viene inibita nei livelli più profondi. “Il trio canonico di memoria, tradizione ed identità”. (106) viene ad essere messo in discussione dallo stesso Cassieri perché.

  19. Il crowdfunding finalizzato al co-finanziamento di progetti di valorizzazione di complessi di elevato valore storico architettonico: il caso di “Torino Esposizioni”

    Directory of Open Access Journals (Sweden)

    Paola Marinò

    2015-12-01

    Full Text Available L’articolo affronta il tema del finanziamento degli interventi di restauro e riuso delle grandi architetture del ‘900, in un momento storico in cui le risorse finanziarie pubbliche sono sempre più scarse e difficili da reperire. La ricerca affronta la possibilità di ricorrere al crowdfunding attraverso il caso studio del progetto di “Torino Esposizioni”, un’architettura del ‘900, parzialmente utilizzata, in stato di degrado, nonostante sia riconosciuta dalla critica internazionale come un’opera di eccezionale valore. A partire dal Master Plan, messo a punto dal Politecnico di Torino in collaborazione con la Città di Torino, è stata simulata l’applicabilità del crowdfunding attraverso un’indagine che valuta la disponibilità a contribuire da parte dei potenziali fruitori del complesso di “Torino Esposizioni” e, quindi, a comprendere l’interesse dei cittadini nei confronti del valore storico del complesso di “Torino Esposizioni” e del progetto di riuso che dovrebbe valorizzarlo. Gli esiti della ricerca, nell’evidenziare un’inattesa scarsa disponibilità a contribuire al finanziamento collettivo del progetto, hanno messo in evidenza, non solo la scarsa conoscenza del crowdfunding come strumento di finanziamento, ma anche la scarsa consapevolezza del valore storico architettonico del patrimonio moderno della città di Torino, di cui “Torino Esposizioni” rappresenta un esempio eccezionale, seppur non l’unico.

  20. Prospettive della reazione di idroformilazione nella sintesi di composti biologicamente attivi

    OpenAIRE

    Marchetti, Mauro

    2000-01-01

    Il nostro gruppo sta conducendo uno studio su complessi di rodio con una nuova classe di leganti idrosolubili di origine proteica, tali complessi impiegati nell’idroformilazione bifasica in solvente acquoso di diversi substrati hanno fornito buoni risultati.

  1. Un sistema di supporto alla decisione per facilitare nuove azioni di finanziamento in ambito pubblico

    Directory of Open Access Journals (Sweden)

    Maria Franca Norese

    2014-12-01

    Full Text Available Un approfondimento analitico sulle modalità di finanziamento che hanno interessato la Regione Piemonte, sviluppato con il contributo di chi vi ha operato direttamente, ha permesso di acquisire, codificare e organizzare importanti elementi di conoscenza e di proporne l’uso per accrescere la cultura valutativa in Regione. Un accresciuto interesse a rendere più efficienti le azioni di finanziamento pubblico ha spinto ad utilizzare i risultati dell’analisi effettuata in un modello multicriteri di valutazione e in un sistema di supporto alla decisione rivolto a facilitare i nuovi processi di finanziamento e rendere operative attività di monitoraggio in un contesto di apprendimento organizzativo.

  2. Parlare di olio. Terminologia della degustazione e tipi di testi

    OpenAIRE

    Silvia Gilardoni

    2013-01-01

    In questo contributo analizziamo la terminologia italiana del settore olivicolo con attenzione ai termini impiegati nella descrizione delle proprietà degustative dell’olio di oliva. Sulla base di un corpus costituito da una documentazione di carattere lessicografico e testuale in lingua italiana presentiamo un’analisi concettuale e terminologica del dominio dell’analisi sensoriale dell’olio. Una parte del lavoro è poi dedicata ad esaminare le modalità espressive e le variazioni terminologiche...

  3. Penanganan Cyber Crime di Sektor Perbankan di Indonesia

    OpenAIRE

    Putra, Prima Agusdani

    2011-01-01

    Di dalam dunia perbankan perkembangan cyber crime cukup mengejutkan dengan terjadi beberapa kasus yang merugikan pihak perbankan seperti; kasus pembobolan BNI New York oleh mantan karyawannya sendiri, mutasi kredit fiktif melalui komputer di BDN Cabang Bintaro Jaya, pencurian dana di Bank Danamon Pusat. Sementara itu sejumlah nasabah pemegang credit card juga mengeluh, karena nomor kartu kreditnya telah dipakai pihak lain untuk melakukan transaksi e-commerce sehingga menimbu...

  4. Fitotossine di Inula viscosa per il controllo di piante parassite

    OpenAIRE

    Avolio, Fabiana

    2013-01-01

    Le piante parassite sono incapaci di sintetizzare dagli elementi minerali e nutritivi materiali sufficienti per la loro crescita e sopperiscono a questa deficienza fisiologica utilizzando le sostanze elaborate dalle piante ospiti, che di conseguenza manifestano generalmente una crescita ridotta. Le Orobanche, la Striga e la Cuscuta sono le piante parassite più diffuse nelle regioni del Mediterraneo e del continente africano interessando colture di rilevanza strategica. Diverse strategie...

  5. Hotel di Kawasan Kenjeran

    OpenAIRE

    Soetjipto, Michael Reinhart

    2014-01-01

    Hotel yang terletak di kawasan Kenjeran ini bertujuan untuk memfasilitasi para wisatawan domestik atau ataupun Internasional. Selain itu seiring dengan pengembangan kenpark yang mulai merencanakan pengembangan fasilitas hiburan serta apartemen yang dapat mendukung dari adanya hotel tersebut sebagai bangunan yang dapat melengkapi komplek tersebut. Fasilitas yang ada saat ini dan cukup ramai dikunjungi masyarakat adalah sebuah tempat ibadah orang tionghoa, banyak masyarakat yang datang untuk be...

  6. Hyperfast Numerical Integration of Ocean Surface Wave Dynamics Extensions to Higher Order

    Science.gov (United States)

    2008-09-30

    Osborne Dipartimento di Fisica Generale, Università di Torino Via Pietro Giuria 1 10125 Torino, Italy Phone: (+39) 11-670-7451 or (+39) 11-329...Universit?i Torino,Dipartimento di Fisica Generale,Via Pietro Giuria 1,10125 Torino, Italy, , 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING

  7. Physics, Nonlinear Time Series Analysis, Data Assimilation and Hyperfast Modeling of Nonlinear Ocean Waves

    Science.gov (United States)

    2010-09-30

    Hyperfast Modeling of Nonlinear Ocean Waves A. R. Osborne Dipartimento di Fisica Generale, Università di Torino Via Pietro Giuria 1, 10125...PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Universit?i Torino,Dipartimento di Fisica Generale,Via Pietro Giuria 1,10125 Torino, Italy, 8. PERFORMING

  8. Mid-Infrared Optoelectronics: Materials and Devices. MIOMD-XII

    Science.gov (United States)

    2014-10-01

    University, 6100 Main Street, Houston, TX 77005‐1827, USA 3Dipartimento Interateneo di Fisica , Università e Politecnico di Bari Via Amendola 173, I‐70126, Bari...Lancaster University, Lancaster, LA1 4YB, UK 2School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK 3Dipartimento di Fisica

  9. Numerical Solution of Hamilton-Jacobi Equations in High Dimension

    Science.gov (United States)

    2012-11-23

    high dimension FA9550-10-1-0029 Maurizio Falcone Dipartimento di Matematica SAPIENZA-Universita di Roma P. Aldo Moro, 2 00185 ROMA AH930...solution of Hamilton-Jacobi equations in high dimension AFOSR contract n. FA9550-10-1-0029 Maurizio Falcone Dipartimento di Matematica SAPIENZA

  10. Definition of dose intensity (DI), average relative DI and effective DI

    International Nuclear Information System (INIS)

    Alberto, P.

    1995-01-01

    The cytotoxic activity of cancer chemotherapy is related to the dose and to the amount of drug delivered per time unit. the significance of time in the effectiveness of a treatment program is frequently overlooked. The term of dose intensity (DI) is used to define the drug dose delivered per time unit and is expressed as mg/m 2 per week. A delay in the sequence of treatment cycles decreases the DI in the DI in the same proportion as a reduction of dose. Average relative DI corresponds to the mean DI of combined agents and is expressed as a fraction of a similar combination selected as a standard. Di is useful to compare the dose actually received with the prescribed dose. The relation of DI with tumor response or survival has not been fully demonstrated. A threshold DI level for therapeutic activity is evident. Above this threshold, a linear relationship of DI and effectiveness is not obvious, particularly regarding high-dose chemotherapy. The term of DI is more useful in its principle than in the significance of its calculated value. (authors). 19 refs., 3 tabs., 3 figs

  11. Narrazioni di narrazioni: orientamento narrativo e progetto di vita (Federico Batini, Gabriel Del Sarto

    Directory of Open Access Journals (Sweden)

    Manuela Ladogana

    2007-03-01

    Full Text Available Il volume, denso di contenuti e ricco di riferimenti teorici, traccia con chiarezza le sue linee di sviluppo ed apre alla riflessione, anche pedagogica, sull’esigenza di recuperare la dimensione narrativa e autobiografica per la realizzazione di una pratica orientativa che guidi e sostenga il soggetto in orientamento verso la riscoperta e ricostruzione del proprio progetto di vita.

  12. Gerakan Filantropi Islam di Amerika

    Directory of Open Access Journals (Sweden)

    Fuad Hasyim

    2018-01-01

    Penelitian bertujuan untuk mengetahui perkembangan gerakan filantropi Islam di Amerika yang meliputi pembahasan tentang basis kelembagaan filantropi Islam dan kontribusinya terhadap solidaritas dan pemberdayaan umat Islam di Amerika. Penelitian ini adalah kajian literatur dengan menggunakan metode penelitian kualitatif dan pendekatan multidisiplin. Hasil penelitian menunjukan empat basis kelembagaan gerakan filantropi Islam di Amerika; yaitu masjid, lembaga pendidikan, etnis dan aliran atau madzhab pemikiran. Didapatkan pula fakta hubungan signifikan antara eksistensi lembaga filantropi Islam terhadap kebijakan politik pemerintah terkait isu radikalisme yang melekat pada umat Islam di Amerika. Kata Kunci : Amerika, Filantropi, Islam, Muslim

  13. La filosofia clinica di Wittgenstein

    Directory of Open Access Journals (Sweden)

    Lorenzo Ghirelli

    2017-01-01

    Full Text Available Intento del presente saggio è quello di tracciare le linee principali della filosofia di Wittgenstein definendone l’orizzonte operativo e la strategia d’azione. Seguiremo inizialmente i cambiamenti nella concezione del linguaggio e del significato del filosofo austriaco utilizzandoli come traccia per registrare le corrispondenti revisioni degli obiettivi, delle tecniche e delle forme del far filosofia da lui proposte. Cercheremo poi di analizzare la pratica filosofica prospettata dal Wittgenstein maturo evidenziandone alcuni aspetti che ci consentiranno di qualificarla come clinica.

  14. Il viaggio gastronomico di Paolo Monelli

    Directory of Open Access Journals (Sweden)

    Alberto Salarelli

    2013-01-01

    Full Text Available Il ghiottone errante di Paolo Monelli, pubblicato nel 1935, rappresenta uno dei primi esempi di narrativa di viaggio in tema di enogastronomia, un genere destinato a grande successo nel secondo dopoguerra. In questo articolo, oltre a ripercorrere la vicenda biografica di Monelli, si sottolineano le relazioni tra Il ghiottone e la cultura gastronomica del regime fascista, e si evidenziano alcuni tratti caratteristici del suo stile di scrittura.

  15. Il museo della scienza di Villa Farnesina

    Directory of Open Access Journals (Sweden)

    Francesca Salvemini

    2005-02-01

    Full Text Available Rappresentavano l’Astronomia le due logge romane del viridario di villa Farnesina con la Sala adiacente del Trionfo di Ercole: lo spazio, l’astrolabio zodiacale della Sala di Galatea - in testa le stelle dell’Orsa minore fatte di “sasso” da Medusa, Peruzzi nella biografia di Vasari - e il tempo, la meccanica dello gnomone solare del Trionfo di Cupido.

  16. Il viaggio gastronomico di Paolo Monelli.

    OpenAIRE

    Salarelli, Alberto

    2013-01-01

    Il ghiottone errante di Paolo Monelli, pubblicato nel 1935, rappresenta uno dei primi esempi di narrativa di viaggio in tema di enogastronomia, un genere destinato a grande successo nel secondo dopoguerra. In questo articolo, oltre a ripercorrere la vicenda biografica di Monelli, si sottolineano le relazioni tra Il ghiottone e la cultura gastronomica del regime fascista, e si evidenziano alcuni tratti caratteristici del suo stile di scrittura. Paolo Monelli‟s Il ghiottone errante (The Wand...

  17. A method for three-dimensional interfacial particle image velocimetry (3D-IPIV) of an air–water interface

    International Nuclear Information System (INIS)

    Turney, Damon E; Anderer, Angelika; Banerjee, Sanjoy

    2009-01-01

    A new stereoscopic method for collecting particle image velocimetry (PIV) measurements within ∼1 mm of a wavy air–water interface with simultaneous measurements of the morphology of the interface is described. The method, termed three-dimensional interfacial particle image velocimetry (3D-IPIV), is tested in a wind wave channel with a wind speed of 5.8 m s −1 , water depth of 10 cm and a fetch of ∼9 m. Microscale breaking waves populate the interface and their flow patterns are clearly visible in the velocimetry results. The associated capillary waves and surface divergence patterns are observed. Several statistical measurements of the flow are compared with independent measurements and good agreement is found. The method shows great promise for investigating the transfer of momentum, heat and gases across an air–water interface, both in the laboratory and in field settings. Additional methods are described for manufacturing the flow tracers needed for the 3D-IPIV method. These tracers are likely to be useful for other researchers, and have the characteristics of being fluorescent, neutrally buoyant, non-toxic, monodisperse, inexpensive and easy to manufacture

  18. Computational fluid dynamics and particle image velocimetry assisted design tools for a new generation of trochoidal gear pumps

    Directory of Open Access Journals (Sweden)

    M Garcia-Vilchez

    2015-06-01

    Full Text Available Trochoidal gear pumps produce significant flow pulsations that result in pressure pulsations, which interact with the system where they are connected, shortening the life of both the pump and circuit components. The complicated aspects of the operation of a gerotor pump make computational fluid dynamics the proper tool for modelling and simulating its flow characteristics. A three-dimensional model with deforming mesh computational fluid dynamics is presented, including the effects of the manufacturing tolerance and the leakage inside the pump. A new boundary condition is created for the simulation of the solid contact in the interteeth radial clearance. The experimental study of the pump is carried out by means of time-resolved particle image velocimetry, and results are qualitatively evaluated, thanks to the numerical simulation results. Time-resolved particle image velocimetry is developed in order to adapt it to the gerotor pump, and it is proved to be a feasible alternative to obtain the instantaneous flow of the pump in a direct mode, which would allow the determination of geometries that minimize the non-desired flow pulsations. Thus, a new methodology involving computational fluid dynamics and time-resolved particle image velocimetry is presented, which allows the obtaining of the instantaneous flow of the pump in a direct mode without altering its behaviour significantly.

  19. Particle image velocimetry and infrared thermography in a levitated droplet with nanosilica suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Abhishek; Kumar, Ranganathan [University of Central Florida, Department of Mechanical Materials and Aerospace Engineering, Orlando, FL (United States); Basu, Saptarshi [Indian Institute of Science, Department of Mechanical Engineering, Bangalore (India)

    2012-03-15

    Preferential accumulation and agglomeration kinetics of nanoparticles suspended in an acoustically levitated water droplet under radiative heating has been studied. Particle image velocimetry performed to map the internal flow field shows a single cell recirculation with increasing strength for decreasing viscosities. Infrared thermography and high speed imaging show details of the heating process for various concentrations of nanosilica droplets. Initial stage of heating is marked by fast vaporization of liquid and sharp temperature rise. Following this stage, aggregation of nanoparticles is seen resulting in various structure formations. At low concentrations, a bowl structure of the droplet is dominant, maintained at a constant temperature. At high concentrations, viscosity of the solution increases, leading to rotation about the levitator axis due to the dominance of centrifugal motion. Such complex fluid motion inside the droplet due to acoustic streaming eventually results in the formation of a ring structure. This horizontal ring eventually reorients itself due to an imbalance of acoustic forces on the ring, exposing larger area for laser absorption and subsequent sharp temperature rise. (orig.)

  20. A tomographic particle image velocimetry investigation of the flow development over dual step cylinders

    Energy Technology Data Exchange (ETDEWEB)

    Morton, C., E-mail: chris.morton@ucalgary.ca [Department of Mechanical and Manufacturing Engineering, University of Calgary, 2500 University Dr NW, Calgary, Alberta T2N 1N4 (Canada); Yarusevych, S. [Department of Mechanical and Mechatronics Engineering, University of Waterloo, 200 University Ave W, Waterloo, Ontario N2L 3G1 (Canada); Scarano, F. [Department of Aerospace Engineering, Delft University of Technology, 2628 Delft (Netherlands)

    2016-02-15

    This experimental study focuses on the near wake development of a dual step cylinder geometry consisting of a long base cylinder of diameter d to which a larger diameter (D) cylinder of length L is attached coaxially at mid-span. The experiments cover a range of Reynolds numbers, 2000 ≤ Re{sub D} ≤ 5000, diameter ratios, 1.33 ≤ D/d ≤ 2.0 and large cylinder aspect ratios, 0.5 ≤ L/D ≤ 5 using Tomographic particle image velocimetry. Distinct changes in wake topology are observed varying the above parameters. Supporting previous experimental studies on the same geometry involving flow visualization and planar measurements, four distinct flow regimes are identified to which a distinct three-dimensional wake topology can be associated. The vortex-dominated wake dynamical behaviour is investigated with Proper Orthogonal Decomposition (POD) and conditional averaging of three-dimensional velocity fields is used to exemplify the different shedding regimes. The conditionally averaged flow fields are shown to quantitatively resolve flow features equivalent to those obtained from a reduced order model consisting of the first ten to twenty POD modes, identifying the dominant vortex shedding cells and their interactions.

  1. Small-scale deflagration cylinder test with velocimetry wall-motion diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Hooks, Daniel E [Los Alamos National Laboratory; Hill, Larry G [Los Alamos National Laboratory; Pierce, Timothy H [Los Alamos National Laboratory

    2010-01-01

    Predicting the likelihood and effects of outcomes resultant from thermal initiation of explosives remains a significant challenge. For certain explosive formulations, the general outcome can be broadly predicted given knowledge of certain conditions. However, there remain unexplained violent events, and increased statistical understanding of outcomes as a function of many variables, or 'violence categorization,' is needed. Additionally, the development of an equation of state equivalent for deflagration would be very useful in predicting possible detailed event consequences using traditional hydrodynamic detonation moders. For violence categorization, it is desirable that testing be efficient, such that it is possible to statistically define outcomes reliant on the processes of initiation of deflagration, steady state deflagration, and deflagration to detonation transitions. If the test simultaneously acquires information to inform models of violent deflagration events, overall predictive capabilities for event likelihood and consequence might improve remarkably. In this paper we describe an economical scaled deflagration cylinder test. The cyclotetramethylene tetranitramine (HMX) based explosive formu1lation PBX 9501 was tested using different temperature profiles in a thick-walled copper cylindrical confiner. This test is a scaled version of a recently demonstrated deflagration cylinder test, and is similar to several other thermal explosion tests. The primary difference is the passive velocimetry diagnostic, which enables measurement of confinement vessel wall velocities at failure, regardless of the timing and location of ignition.

  2. Krypton tagging velocimetry in a turbulent Mach 2.7 boundary layer

    Science.gov (United States)

    Zahradka, D.; Parziale, N. J.; Smith, M. S.; Marineau, E. C.

    2016-05-01

    The krypton tagging velocimetry (KTV) technique is applied to the turbulent boundary layer on the wall of the "Mach 3 Calibration Tunnel" at Arnold Engineering Development Complex (AEDC) White Oak. Profiles of velocity were measured with KTV and Pitot-pressure probes in the Mach 2.7 turbulent boundary layer comprised of 99 % {N}2/1 % Kr at momentum-thickness Reynolds numbers of {Re}_{\\varTheta }= 800, 1400, and 2400. Agreement between the KTV- and Pitot-derived velocity profiles is excellent. The KTV and Pitot velocity data follow the law of the wall in the logarithmic region with application of the Van Driest I transformation. The velocity data are analyzed in the outer region of the boundary layer with the law of the wake and a velocity-defect law. KTV-derived streamwise velocity fluctuation measurements are reported and are consistent with data from the literature. To enable near-wall measurement with KTV (y/δ ≈ 0.1-0.2), an 800-nm longpass filter was used to block the 760.2-nm read-laser pulse. With the longpass filter, the 819.0-nm emission from the re-excited Kr can be imaged to track the displacement of the metastable tracer without imaging the reflection and scatter from the read-laser off of solid surfaces. To operate the Mach 3 AEDC Calibration Tunnel at several discrete unit Reynolds numbers, a modification was required and is described herein.

  3. Local velocity measurements in lead-bismuth and sodium flows using the ultrasound doppler velocimetry

    International Nuclear Information System (INIS)

    Eckert, S.; Gerbeth, G.

    2003-01-01

    We will present measurements of the velocity profiles in liquid sodium and eutectic lead-bismuth by means of the Ultrasonic Doppler Velocimetry (UDV). A sodium flow in a rectangular duct exposed to an external, transverse magnetic field has been examined. To demonstrate the capability of UDV the transformation of the well-known turbulent, piston-like profile to an M-shaped velocity profile for growing magnetic field strength was observed. The significance of artifacts such as caused by the existence of reflecting interfaces in the measuring domain will be discussed. In the sodium case, the measurements were performed through the channel wall. An integrated ultrasonic sensor with acoustic wave-guide has been developed to overcome the limitation of ultrasonic transducers to temperatures lower than 200 .deg. C. This sensor can presently be applied at maximum temperatures up to 800 .deg. C. Stable and robust measurements have been performed in various PbBi flows in our laboratory at FZR as well as at the THESYS loop of the KALLA laboratory of the ForschungsZentrum Karlsruhe (FZK). We will also present experimental results obtained in a PbBi bubbly flow at 250...300 .deg. C. Argon bubbles were injected through a single orifice in a cylindrical container filled with stagnant PbBi. Velocity profiles were measured in the bubble plume. Mean values of the liquid as well as the bubble velocity were extracted from the data and will be presented as function of the gas flow rate

  4. Velocity profile measurement of lead-lithium flows by high-temperature ultrasonic doppler velocimetry

    International Nuclear Information System (INIS)

    Ueki, Y.; Kunugi, T.; Hirabayashi, Masaru; Nagai, Keiichi; Saito, Junichi; Ara, Kuniaki; Morley, N.B.

    2014-01-01

    This paper describes a high-temperature ultrasonic Doppler Velocimetry (HT-UDV) technique that has been successfully applied to measure velocity profiles of the lead-lithium eutectic alloy (PbLi) flows. The impact of tracer particles is investigated to determine requirements for HT-UDV measurement of PbLi flows. The HT-UDV system is tested on a PbLi flow driven by a rotating-disk in an inert atmosphere. We find that a sufficient amount of particles contained in the molten PbLi are required to successfully measure PbLi velocity profiles by HT-UDV. An X-ray diffraction analysis is performed to identify those particles in PbLi, and indicates that those particles were made of the lead mono-oxide (PbO). Since the specific densities of PbLi and PbO are close to each other, the PbO particles are expected to be well-dispersed in the bulk of molten PbLi. We conclude that the excellent dispersion of PbO particles enables in HT-UDV to obtain reliable velocity profiles for operation times of around 12 hours. (author)

  5. Particle image velocimetry measurements of the flow in the converging region of two parallel jets

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huhu, E-mail: huhuwang@tamu.edu; Lee, Saya, E-mail: sayalee@tamu.edu; Hassan, Yassin A., E-mail: y-hassan@tamu.edu

    2016-09-15

    Highlights: • The flow behaviors in the converging region were non-intrusively investigated using PIV. • The PIV results using two measuring scales and LDV data matched very well. • Significant momentum transfer was observed in the merging region right after the merging point. • Instantaneous vector field revealed characteristic interacting patterns of the jets. - Abstract: The interaction between parallel jets plays a critical role in determining the characteristics of the momentum and heat transfer in the flow. Specifically for next generation VHTR, the output temperature will be about 900 °C, and any thermal oscillations will create safety issues. The mixing variations of the coolants in the reactor core may influence these power oscillations. Numerous numerical tools such as computational fluid dynamics (CFD) simulations have been used to support the reactor design. The validation of CFD method is important to ensure the fidelity of the calculations. This requires high-fidelity, qualified benchmark data. Particle image velocimetry (PIV), a non-intrusive measuring technique, was used to provide benchmark data for resolving a simultaneous flow field in the converging region of two submerged parallel jets issued from rectangular channels. The jets studied in this work had an equal discharge velocity at room temperature. The turbulent characteristics including the distributions of mean velocities, turbulence intensities, Reynolds stresses and z-component vorticity were studied. The streamwise mean velocity measured by PIV and LDV were compared, and they agreed very well.

  6. Ultrasonic particle image velocimetry for improved flow gradient imaging: algorithms, methodology and validation

    International Nuclear Information System (INIS)

    Niu Lili; Qian Ming; Yu Wentao; Jin Qiaofeng; Ling Tao; Zheng Hairong; Wan Kun; Gao Shen

    2010-01-01

    This paper presents a new algorithm for ultrasonic particle image velocimetry (Echo PIV) for improving the flow velocity measurement accuracy and efficiency in regions with high velocity gradients. The conventional Echo PIV algorithm has been modified by incorporating a multiple iterative algorithm, sub-pixel method, filter and interpolation method, and spurious vector elimination algorithm. The new algorithms' performance is assessed by analyzing simulated images with known displacements, and ultrasonic B-mode images of in vitro laminar pipe flow, rotational flow and in vivo rat carotid arterial flow. Results of the simulated images show that the new algorithm produces much smaller bias from the known displacements. For laminar flow, the new algorithm results in 1.1% deviation from the analytically derived value, and 8.8% for the conventional algorithm. The vector quality evaluation for the rotational flow imaging shows that the new algorithm produces better velocity vectors. For in vivo rat carotid arterial flow imaging, the results from the new algorithm deviate 6.6% from the Doppler-measured peak velocities averagely compared to 15% of that from the conventional algorithm. The new Echo PIV algorithm is able to effectively improve the measurement accuracy in imaging flow fields with high velocity gradients.

  7. Visualization of nasal airflow patterns in a patient affected with atrophic rhinitis using particle image velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, G J M [Hamner Institutes for Health Sciences, NC (United States); Mitchell, G [The Queens University of Belfast, Belfast (United Kingdom); Bailie, N [The Queens University of Belfast, Belfast (United Kingdom); Thornhill, D [The Queens University of Belfast, Belfast (United Kingdom); Watterson, J [The Queens University of Belfast, Belfast (United Kingdom); Kimbell, J S [Hamner Institutes for Health Sciences, NC (United States)

    2007-10-15

    The relationship between airflow patterns in the nasal cavity and nasal function is poorly understood. This paper reports an experimental study of the interplay between symptoms and airflow patterns in a patient affected with atrophic rhinitis. This pathology is characterized by mucosal dryness, fetor, progressive atrophy of anatomical structures, a spacious nasal cavity, and a paradoxical sensation of nasal congestion. A physical replica of the patient's nasal geometry was made and particle image velocimetry (PIV) was used to visualize and measure the flow field. The nasal replica was based on computed tomography (CT) scans of the patient and was built in three steps: three-dimensional reconstruction of the CT scans; rapid prototyping of a cast; and sacrificial use of the cast to form a model of the nasal passage in clear silicone. Flow patterns were measured by running a water-glycerol mixture through the replica and evaluating the displacement of particles dispersed in the liquid using PIV. The water-glycerol flow rate used corresponded to an air flow rate representative of a human breathing at rest. The trajectory of the flow observed in the left passage of the nose (more affected by atrophic rhinitis) differed markedly from what is considered normal, and was consistent with patterns of epithelial damage observed in cases of the condition. The data are also useful for validation of computational fluid dynamics predictions.

  8. Study of particles clouds ejected under shock: the contributions of Photonic Doppler Velocimetry

    International Nuclear Information System (INIS)

    Prudhomme, Gabriel

    2014-01-01

    A metal plate subjected to a shock (tin, 10 GPa) undergoes a variety of damages such as spalling or the ejection of a cloud of particles. Two main mechanisms govern the formation of this cloud: the micro-jetting and the melting under shock. Photonic Doppler Velocimetry (PDV, a.k.a. LDV or het-V) is a multi-velocity time-resolved diagnostic. Developed from 2000's, the all-fibered conception makes its integration easy into shock experiments. The purpose of the thesis is to describe the contributions of PDV systems for high-velocity (several km/s) particle-cloud characterization, including micro-jetting cloud. This document presents a state of the art of shock generators, diagnostics and (numerical and experimental) studies involved in metallic micro-machined jetting. An extensive study of a PDV system is proposed. It leads to the definition of time-velocity spectrogram, evaluated in units of collected power, and a detection capability limit. Thanks to photon diffusion models, a threshold in the diameter of the measured particle is estimated. A PDV spectrogram simulation program is shown within the framework of particle clouds. Finally, several experimental campaigns are exposed. They emphasize the remarkable capacities of the system; results are compared to simulations. Diameter distributions are inferred using slowing down in air or in other gazes. Some radiometric analyses are also performed. (author) [fr

  9. Comparison of Global Sizing Velocimetry and Phase Doppler Anemometry measurements of alternative jet fuel sprays

    Science.gov (United States)

    Sadr, Reza; Kannaiyan, Kumaran

    2013-11-01

    Atomization plays a crucial precursor role in liquid fuel combustion that directly affects the evaporation, mixing, and emission levels. Laser diagnostic techniques are often used to study the spray characteristics of liquid fuels. The objective of this work is to compare the spray measurements of Gas-to Liquid (GTL) jet fuels obtained using Global Sizing Velocimetry (GSV) and Phase Doppler Anemometry (PDA) techniques at global and local levels, respectively. The chemical and physical properties of GTL fuels are different from conventional jet fuels, owing to the difference in their production methodology. In this work, the experimental facility, the measurement techniques, and spray characteristics of two different GTL fuels are discussed and compared with those of Jet A-1 fuel. Results clearly demonstrate that although the global measurement gives an overall picture of the spray, fine details are obtained only through local measurements and complement in gaining more inferences into the spray characteristics. The results also show a close similarity in spray characteristics between GTL and Jet A-1 fuels. Funded by Qatar Science and Technology Park.

  10. Velocity Deficits in the Wake of Model Lemon Shark Dorsal Fins Measured with Particle Image Velocimetry

    Science.gov (United States)

    Terry, K. N.; Turner, V.; Hackett, E.

    2017-12-01

    Aquatic animals' morphology provides inspiration for human technological developments, as their bodies have evolved and become adapted for efficient swimming. Lemon sharks exhibit a uniquely large second dorsal fin that is nearly the same size as the first fin, the hydrodynamic role of which is unknown. This experimental study looks at the drag forces on a scale model of the Lemon shark's unique two-fin configuration in comparison to drag forces on a more typical one-fin configuration. The experiments were performed in a recirculating water flume, where the wakes behind the scale models are measured using particle image velocimetry. The experiments are performed at three different flow speeds for both fin configurations. The measured instantaneous 2D distributions of the streamwise and wall-normal velocity components are ensemble averaged to generate streamwise velocity vertical profiles. In addition, velocity deficit profiles are computed from the difference between these mean streamwise velocity profiles and the free stream velocity, which is computed based on measured flow rates during the experiments. Results show that the mean velocities behind the fin and near the fin tip are smallest and increase as the streamwise distance from the fin tip increases. The magnitude of velocity deficits increases with increasing flow speed for both fin configurations, but at all flow speeds, the two-fin configurations generate larger velocity deficits than the one-fin configurations. Because the velocity deficit is directly proportional to the drag force, these results suggest that the two-fin configuration produces more drag.

  11. Flow mapping of multiphase flows using a novel single stem endoscopic particle image velocimetry instrument

    International Nuclear Information System (INIS)

    Lad, N; Adebayo, D; Aroussi, A

    2011-01-01

    Particle image velocimetry (PIV) is a successful flow mapping technique which can optically quantify large portions of a flow regime. This enables the method to be completely non-intrusive. The ability to be non-intrusive to any flow has allowed PIV to be used in a large range of industrial sectors for many applications. However, a fundamental disadvantage of the conventional PIV technique is that it cannot easily be used with flows which have no or limited optical access. Flows which have limited optical access for PIV measurement have been addressed using endoscopic PIV techniques. This system uses two separate probes which relay a light sheet and imaging optics to a planar position within the desired flow regime. This system is effective in medical and engineering applications. The present study has been involved in the development of a new endoscopic PIV system which integrates the illumination and imaging optics into one rigid probe. This paper focuses on the validation of the images taken from the novel single stem endoscopic PIV system. The probe is used within atomized spray flow and is compared with conventional PIV measurement and also pitot-static data. The endoscopic PIV system provides images which create localized velocity maps that are comparable with the global measurement of the conventional PIV system. The velocity information for both systems clearly show similar results for the spray characterization and are also validated using the pitot-static data

  12. A 3D velocimetry study of the flow through prosthetic heart valves

    Science.gov (United States)

    Ledesma, R.; Zenit, R.; Pulos, G.; Sanchez, E.; Juarez, A.

    2006-11-01

    Blood damage commonly appears in medical valve prothesis. It is a mayor concern for the designers and surgeons. It is well known that this damage and other complications result from the modified fluid dynamics through the replacement valve. To evaluate the performance of prosthetic heart valves, it is necessary to study the flow through them. To conduct this study , we have built a flow channel that emulates cardiac conditions and allows optical access such that a 3D-PIV velocimetry system could be used. The experiments are aimed to reconstruct the downstream structure of the flow through a mechanical and a bio-material tricuspid heart valve prothesis. Preliminary results show that the observed coherent structures can be related with haemolysis and trombosis, illnesses commonly found in valve prothesis recipients. The mean flow, the levels of strain rate and the turbulence intensity generated by the valves can also be directly related to blood damage. In general, bio-material made valves tend to reduce these complications.

  13. Experimental characterization of solid particle transport by slug flow using Particle Image Velocimetry

    International Nuclear Information System (INIS)

    Goharzadeh, A; Rodgers, P

    2009-01-01

    This paper presents an experimental study of gas-liquid slug flow on solid particle transport inside a horizontal pipe with two types of experiments conducted. The influence of slug length on solid particle transportation is characterized using high speed photography. Using combined Particle Image Velocimetry (PIV) with Refractive Index Matching (RIM) and fluorescent tracers (two-phase oil-air loop) the velocity distribution inside the slug body is measured. Combining these experimental analyses, an insight is provided into the physical mechanism of solid particle transportation due to slug flow. It was observed that the slug body significantly influences solid particle mobility. The physical mechanism of solid particle transportation was found to be discontinuous. The inactive region (in terms of solid particle transport) upstream of the slug nose was quantified as a function of gas-liquid composition and solid particle size. Measured velocity distributions showed a significant drop in velocity magnitude immediately upstream of the slug nose and therefore the critical velocity for solid particle lifting is reached further upstream.

  14. Ghost Particle Velocimetry implementation in millimeters devices and comparison with μPIV

    Science.gov (United States)

    Riccomi, Marco; Alberini, Federico; Brunazzi, Elisabetta; Vigolo, Daniele

    2016-11-01

    Micro/milli-fluidic devices are becoming an important reference for several disciplines and are quickly increasing their applications in scientific, as well as industrial, environment. As a consequence, the development of techniques able to analyse these kinds of systems is required to allow their progress. Here we show the implementation of the Ghost Particle Velocimetry (GPV) for the flow velocity field investigation in milli-fluidic devices. This innovative technique has been recently introduced, and has been already proven to be useful in describing rapid phenomenon at a small scale. In this work, the GPV has been used to characterize the trapping of light suspended material in a branching junction. Experiments have been performed to identify the flow velocity field close to a millimeters scale T-junction, at different Reynolds numbers. Particularly interesting are the complex structures, such as vortices and recirculation zones, induced by the vortex breakdown phenomenon. The results obtained have been deeply validated and compared with the well-established μPIV, highlighting the differences in terms of qualitative and quantitative parameters. A performance comparison has been designed to underline the strengths and weaknesses of the two experimental techniques.

  15. Visualization of air flow around soccer ball using a particle image velocimetry

    Science.gov (United States)

    Hong, Sungchan; Asai, Takeshi; Seo, Kazuya

    2015-10-01

    A traditional soccer ball is constructed using 32 pentagonal and hexagonal panels. In recent years, however, the likes of the Teamgeist and Jabulani balls, constructed from 14 and 8 panels, respectively, have entered the field, marking a significant departure from conventionality in terms of shape and design. Moreover, the recently introduced Brazuca ball features a new 6-panel design and has already been adopted by many soccer leagues. However, the shapes of the constituent panels of these balls differ substantially from those of conventional balls. Therefore, this study set out to investigate the flight and aerodynamic characteristics of different orientations of the soccer ball, which is constructed from panels of different shapes. A wind tunnel test showed substantial differences in the aerodynamic forces acting on the ball, depending on its orientation. Substantial differences were also observed in the aerodynamic forces acting on the ball in different directions, corresponding to its orientation and rotation. Moreover, two-dimensional particle image velocimetry (2D-PIV) measurements showed that the boundary separation varies depending on the orientation of the ball. Based on these results, we can conclude that the shape of the panels of a soccer ball substantially affects its flight trajectory.

  16. Aortic isthmus Doppler velocimetry: role in assessment of preterm fetal growth restriction.

    LENUS (Irish Health Repository)

    Kennelly, M M

    2012-02-01

    Intrauterine fetal growth restriction (IUGR) is an important pregnancy complication associated with significant adverse clinical outcome, stillbirth, perinatal morbidity and cerebral palsy. To date, no uniformly accepted management protocol of Doppler surveillance that reduces mortality and cognitive morbidity has emerged. Aortic isthmus (AoI) evaluation has been proposed as a potential monitoring tool for IUGR fetuses. In this review, the current knowledge of the relationship between AoI Doppler velocimetry and preterm fetal growth restriction is reviewed. Relevant technical aspects and reproducibility data are reviewed as we discuss AoI Doppler and its place within the existing repertoire of Doppler assessments in placental insufficiency. The AoI is a link between the right and left ventricles which perfuse the lower and upper body, respectively. The clinical use of AoI waveforms for monitoring fetal deterioration in IUGR has been limited, but preliminary work suggests that abnormal AoI impedance indices are an intermediate step between placental insufficiency-hypoxemia and cardiac decompensation. Further prospective studies correlating AoI indices with arterial and venous Doppler indices and perinatal outcome are required before encorporating this index into clinical practice.

  17. A review on noise suppression and aberration compensation in holographic particle image velocimetry

    Directory of Open Access Journals (Sweden)

    K.F. Tamrin

    2016-12-01

    Full Text Available Understanding three-dimensional (3D fluid flow behaviour is undeniably crucial in improving performance and efficiency in a wide range of applications in engineering and medical fields. Holographic particle image velocimetry (HPIV is a potential tool to probe and characterize complex flow dynamics since it is a truly three-dimensional three-component measurement technique. The technique relies on the coherent light scattered by small seeding particles that are assumed to faithfully follow the flow for subsequent reconstruction of the same the event afterward. However, extraction of useful 3D displacement data from these particle images is usually aggravated by noise and aberration which are inherent within the optical system. Noise and aberration have been considered as major hurdles in HPIV in obtaining accurate particle image identification and its corresponding 3D position. Major contributions to noise include zero-order diffraction, out-of-focus particles, virtual image and emulsion grain scattering. Noise suppression is crucial to ensure that particle image can be distinctly differentiated from background noise while aberration compensation forms particle image with high integrity. This paper reviews a number of HPIV configurations that have been proposed to address these issues, summarizes the key findings and outlines a basis for follow-on research.

  18. A blood-mimicking fluid for particle image velocimetry with silicone vascular models

    Science.gov (United States)

    Yousif, Majid Y.; Holdsworth, David W.; Poepping, Tamie L.

    2011-03-01

    For accurate particle image velocimetry measurements in hemodynamics studies, it is important to use a fluid with a refractive index ( n) matching that of the vascular models (phantoms) and ideally a dynamic viscosity matching human blood. In this work, a blood-mimicking fluid (BMF) composed of water, glycerol, and sodium iodide was formulated for a range of refractive indices to match most common silicone elastomers ( n = 1.40-1.43) and with corresponding dynamic viscosity within the average cited range of healthy human blood (4.4 ± 0.5 cP). Both refractive index and viscosity were attained at room temperature (22.2 ± 0.2°C), which eliminates the need for a temperature-control system. An optimally matched BMF, suitable for use in a vascular phantom ( n = 1.4140 ± 0.0008, Sylgard 184), was demonstrated with composition (by weight) of 47.38% water, 36.94% glycerol (44:56 glycerol-water ratio), and 15.68% sodium iodide salt, resulting in a dynamic viscosity of 4 .31 ± 0 .03 cP.

  19. Deriving a blood-mimicking fluid for particle image velocimetry in Sylgard-184 vascular models.

    Science.gov (United States)

    Yousif, Majid Y; Holdsworth, David W; Poepping, Tamie L

    2009-01-01

    A new blood-mimicking fluid (BMF) has been developed for particle image velocimetry (PIV), which enables flow studies in vascular models (phantoms). A major difficulty in PIV that affects measurement accuracy is the refraction and distortion of light passing through the interface between the model and the fluid, due to the difference in refractive index (n) between the two materials. The problem can be eliminated by using a fluid with a refractive index matching that of the model. Such fluids are not commonly available, especially for vascular research where the fluid should also have a viscosity similar to human blood. In this work, a blood-mimicking fluid, composed of water (47.38% by weight), glycerol (36.94% by weight) and sodium iodide salt (15.68% by weight), was developed for compatibility with our silicone (Sylgard 184; n = 1.414) phantoms. The fluid exhibits a dynamic viscosity of 4.31+/-0.03 cP which lies within the range of human blood viscosity (4.4+/-0.6 cP). Both refractive index and viscosity were attained at 22.2+/-0.2 degrees C, which is a feasible room temperature, thus eliminating the need for a temperature-control system. The fluid will be used to study hemodynamics in vascular flow models fabricated from Sylgard 184.

  20. Identification of hydrodynamic forces around 3D surrogates using particle image velocimetry in a microfluidic channel

    Science.gov (United States)

    Afshar, Sepideh; Nath, Shubhankar; Demirci, Utkan; Hasan, Tayyaba; Scarcelli, Giuliano; Rizvi, Imran; Franco, Walfre

    2018-02-01

    Previous studies have demonstrated that flow-induced shear stress induces a motile and aggressive tumor phenotype in a microfluidic model of 3D ovarian cancer. However, the magnitude and distribution of the hydrodynamic forces that influence this biological modulation on the 3D cancer nodules are not known. We have developed a series of numerical and experimental tools to identify these forces within a 3D microchannel. In this work, we used particle image velocimetry (PIV) to find the velocity profile using fluorescent micro-spheres as surrogates and nano-particles as tracers, from which hydrodynamic forces can be derived. The fluid velocity is obtained by imaging the trajectory of a range of florescence nano-particles (500-800 μm) via confocal microscopy. Imaging was done at different horizontal planes and with a 50 μm bead as the surrogate. For an inlet current rate of 2 μl/s, the maximum velocity at the center of the channel was 51 μm/s. The velocity profile around the sphere was symmetric which is expected since the flow is dominated by viscous forces as opposed to inertial forces. The confocal PIV was successfully employed in finding the velocity profile in a microchannel with a nodule surrogate; therefore, it seems feasible to use PIV to investigate the hydrodynamic forces around 3D biological models.

  1. Photonic-Doppler-Velocimetry, Paraxial-Scalar Diffraction Theory and Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Ambrose, W. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-07-20

    In this report I describe current progress on a paraxial, scalar-field theory suitable for simulating what is measured in Photonic Doppler Velocimetry (PDV) experiments in three dimensions. I have introduced a number of approximations in this work in order to bring the total computation time for one experiment down to around 20 hours. My goals were: to develop an approximate method of calculating the peak frequency in a spectral sideband at an instant of time based on an optical diffraction theory for a moving target, to compare the ‘measured’ velocity to the ‘input’ velocity to gain insights into how and to what precision PDV measures the component of the mass velocity along the optical axis, and to investigate the effects of small amounts of roughness on the measured velocity. This report illustrates the progress I have made in describing how to perform such calculations with a full three dimensional picture including tilted target, tilted mass velocity (not necessarily in the same direction), and small amounts of surface roughness. With the method established for a calculation at one instant of time, measured velocities can be simulated for a sequence of times, similar to the process of sampling velocities in experiments. Improvements in these methods are certainly possible at hugely increased computational cost. I am hopeful that readers appreciate the insights possible at the current level of approximation.

  2. Vortex ring formation at the open end of a shock tube: A particle image velocimetry study

    Science.gov (United States)

    Arakeri, J. H.; Das, D.; Krothapalli, A.; Lourenco, L.

    2004-04-01

    The vortex ring generated subsequent to the diffraction of a shock wave from the open end of a shock tube is studied using particle image velocimetry. We examine the early evolution of the compressible vortex ring for three-exit shock Mach numbers, 1.1, 1.2, and 1.3. For the three cases studied, the ring formation is complete at about tUb/D=2, where t is time, Ub is fluid velocity behind shock as it exits the tube and D is tube diameter. Unlike in the case of piston generated incompressible vortex rings where the piston velocity variation with time is usually trapezoidal, in the shock-generated vortex ring case the exit fluid velocity doubles from its initial value Ub before it slowly decays to zero. At the end of the ring formation, its translation speed is observed to be about 0.7 Ub. During initial formation and propagation, a jet-like flow exists behind the vortex ring. The vortex ring detachment from the tailing jet, commonly referred to as pinch-off, is briefly discussed.

  3. Measurement of fast-changing low velocities by photonic Doppler velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Song Hongwei; Wu Xianqian; Huang Chenguang; Wei Yangpeng; Wang Xi [Key Laboratory for Hydrodynamics and Ocean Engineering, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China)

    2012-07-15

    Despite the increasing popularity of photonic Doppler velocimetry (PDV) in shock wave experiments, its capability of capturing low particle velocities while changing rapidly is still questionable. The paper discusses the performance of short time Fourier transform (STFT) and continuous wavelet transform (CWT) in processing fringe signals of fast-changing low velocities measured by PDV. Two typical experiments are carried out to evaluate the performance. In the laser shock peening test, the CWT gives a better interpretation to the free surface velocity history, where the elastic precursor, main plastic wave, and elastic release wave can be clearly identified. The velocities of stress waves, Hugoniot elastic limit, and the amplitude of shock pressure induced by laser can be obtained from the measurement. In the Kolsky-bar based tests, both methods show validity of processing the longitudinal velocity signal of incident bar, whereas CWT improperly interprets the radial velocity of the shocked sample at the beginning period, indicating the sensitiveness of the CWT to the background noise. STFT is relatively robust in extracting waveforms of low signal-to-noise ratio. Data processing method greatly affects the temporal resolution and velocity resolution of a given fringe signal, usually CWT demonstrates a better local temporal resolution and velocity resolution, due to its adaptability to the local frequency, also due to the finer time-frequency product according to the uncertainty principle.

  4. Microfluidic rheometry of a polymer solution by micron resolution particle image velocimetry: a model validation study

    International Nuclear Information System (INIS)

    Hemaka Bandalusena, H C; Zimmerman, William B; Rees, Julia M

    2009-01-01

    The main purpose of this study is to model non-Newtonian fluid flows in microgeometries. Velocity fields of dilute xanthan gum solutions in a microfluidic T-junction have been measured for pressure-driven flow using micron resolution particle image velocimetry (µ-PIV). Xanthan gum at a fixed concentration is a power-law fluid. Varying the concentration changes the rheology, effectively altering the power-law parameters reflecting the changes in the fluid's shear response since viscoelasticity and extensional viscosity are negligible for dilute solutions of this substance. As the flow is forced to turn the corner of the T-junction, a range of shear rates, and hence viscosities, is produced. If this feature could be incorporated into a viscometer, then potentially the constitutive parameters of a complex fluid could be ascertained from a single experiment. A mathematical model based on a finite element technique has been developed to simulate the fluid flow in the experimental system. Model predictions of the velocity field are found to agree well (less than 5% error) with observations, thus validating the model

  5. Estimating Horizontal Displacement between DEMs by Means of Particle Image Velocimetry Techniques

    Directory of Open Access Journals (Sweden)

    Juan F. Reinoso

    2015-12-01

    Full Text Available To date, digital terrain model (DTM accuracy has been studied almost exclusively by computing its height variable. However, the largely ignored horizontal component bears a great influence on the positional accuracy of certain linear features, e.g., in hydrological features. In an effort to fill this gap, we propose a means of measurement different from the geomatic approach, involving fluid mechanics (water and air flows or aerodynamics. The particle image velocimetry (PIV algorithm is proposed as an estimator of horizontal differences between digital elevation models (DEM in grid format. After applying a scale factor to the displacement estimated by the PIV algorithm, the mean error predicted is around one-seventh of the cell size of the DEM with the greatest spatial resolution, and around one-nineteenth of the cell size of the DEM with the least spatial resolution. Our methodology allows all kinds of DTMs to be compared once they are transformed into DEM format, while also allowing comparison of data from diverse capture methods, i.e., LiDAR versus photogrammetric data sources.

  6. Laser correlation velocimetry performance in diesel applications: spatial selectivity and velocity sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Hespel, Camille [Universite d' Orleans, Laboratoire PRISME, Orleans (France); Blaisot, Jean-Bernard; Gazon, Matthieu; Godard, Gilles [CORIA, UMR 6614, CNRS, Universite et INSA de Rouen, Saint Etienne du Rouvray (France)

    2012-07-15

    The characterization of diesel jets in the near field of the nozzle exit still presents challenges for experimenters. Detailed velocity measurements are needed to characterize diesel injector performance and also to establish boundary conditions for CFD codes. The present article examines the efficiency of laser correlation velocimetry (LCV) applied to diesel spray characterization. A new optical configuration based on a long-distance microscope was tested, and special care was taken to examine the spatial selectivity of the technique. Results show that the depth of the measurement volume (along the laser beam) of LCV extends beyond the depth of field of the imaging setup. The LCV results were also found to be particularly sensitive to high-speed elements of a spray. Results from high-pressure diesel jets in a back-pressure environment indicate that this technique is particularly suited to the very near field of the nozzle exit, where the flow is the narrowest and where the velocity distribution is not too large. It is also shown that the performance of the LCV technique is controlled by the filtering and windowing parameters used in the processing of the raw signals. (orig.)

  7. Laser correlation velocimetry performance in diesel applications: spatial selectivity and velocity sensitivity

    Science.gov (United States)

    Hespel, Camille; Blaisot, Jean-Bernard; Gazon, Matthieu; Godard, Gilles

    2012-07-01

    The characterization of diesel jets in the near field of the nozzle exit still presents challenges for experimenters. Detailed velocity measurements are needed to characterize diesel injector performance and also to establish boundary conditions for CFD codes. The present article examines the efficiency of laser correlation velocimetry (LCV) applied to diesel spray characterization. A new optical configuration based on a long-distance microscope was tested, and special care was taken to examine the spatial selectivity of the technique. Results show that the depth of the measurement volume (along the laser beam) of LCV extends beyond the depth of field of the imaging setup. The LCV results were also found to be particularly sensitive to high-speed elements of a spray. Results from high-pressure diesel jets in a back-pressure environment indicate that this technique is particularly suited to the very near field of the nozzle exit, where the flow is the narrowest and where the velocity distribution is not too large. It is also shown that the performance of the LCV technique is controlled by the filtering and windowing parameters used in the processing of the raw signals.

  8. Application of photon Doppler velocimetry to direct impact Hopkinson pressure bars

    Energy Technology Data Exchange (ETDEWEB)

    Lea, Lewis J., E-mail: ll379@cam.ac.uk; Jardine, Andrew P. [SMF Fracture and Shock Physics Group, Cavendish Laboratory, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom)

    2016-02-15

    Direct impact Hopkinson pressure bar systems offer many potential advantages over split Hopkinson pressure bars, including access to higher strain rates, higher strains for equivalent striker velocity and system length, lower dispersion, and faster achievement of force equilibrium. Currently, these advantages are gained at the expense of all information about the striker impacted specimen face, preventing the experimental determination of force equilibrium, and requiring approximations to be made on the sample deformation history. In this paper, we discuss an experimental method and complementary data analysis for using photon Doppler velocimetry to measure surface velocities of the striker and output bars in a direct impact bar experiment, allowing similar data to be recorded as in a split bar system. We discuss extracting velocity and force measurements, and the precision of measurements. Results obtained using the technique are compared to equivalent split bar tests, showing improved stress measurements for the lowest and highest strains in fully dense metals, and improvement for all strains in slow and non-equilibrating materials.

  9. Simultaneous broadband laser ranging and photonic Doppler velocimetry for dynamic compression experiments

    Energy Technology Data Exchange (ETDEWEB)

    La Lone, B. M., E-mail: lalonebm@nv.doe.gov; Marshall, B. R.; Miller, E. K.; Stevens, G. D.; Turley, W. D. [National Security Technologies, LLC, Special Technologies Laboratory, Santa Barbara, California 93111 (United States); Veeser, L. R. [National Security Technologies, LLC, Los Alamos Operations, Los Alamos, New Mexico 87544 (United States)

    2015-02-15

    A diagnostic was developed to simultaneously measure both the distance and velocity of rapidly moving surfaces in dynamic compression experiments, specifically non-planar experiments where integrating the velocity in one direction does not always give the material position accurately. The diagnostic is constructed mainly from fiber-optic telecommunications components. The distance measurement is based on a technique described by Xia and Zhang [Opt. Express 18, 4118 (2010)], which determines the target distance every 20 ns and is independent of the target speed. We have extended the full range of the diagnostic to several centimeters to allow its use in dynamic experiments, and we multiplexed it with a photonic Doppler velocimetry (PDV) system so that distance and velocity histories can be measured simultaneously using one fiber-optic probe. The diagnostic was demonstrated on a spinning square cylinder to show how integrating a PDV record can give an incorrect surface position and how the ranging diagnostic described here obtains it directly. The diagnostic was also tested on an explosive experiment where copper fragments and surface ejecta were identified in both the distance and velocity signals. We show how the distance measurements complement the velocity data. Potential applications are discussed.

  10. Three-dimensional three-component particle velocimetry for microscale flows using volumetric scanning

    International Nuclear Information System (INIS)

    Klein, S A; Moran, J L; Posner, J D; Frakes, D H

    2012-01-01

    We present a diagnostic platform for measuring three-dimensional three-component (3D3C) velocity fields in microscopic volumes. The imaging system uses high-speed Nipkow spinning disk confocal microscopy. Confocal microscopy provides optical sectioning using pinhole spatial filtering which rejects light originating from out-of-focus objects. The system accomplishes volumetric scanning by rapid translation of the high numerical aperture objective using a piezo objective positioner. The motion of fluorescent microspheres is quantified using 3D3C super resolution particle-imaging velocimetry with instantaneous spatial resolutions of the order of 5 µm or less in all three dimensions. We examine 3D3C flow in a PDMS microchannel with an expanding section at 3D acquisition rates of 30 Hz, and find strong agreement with a computational model. Equations from the PIV and PTV literature adapted for a scanning objective provide estimates of maximum measurable velocity. The technique allows for isosurface visualization of 3D particle motion and robust high spatial resolution velocity measurements without requiring a calibration step or reconstruction algorithms. (paper)

  11. Pressure from particle image velocimetry for convective flows: a Taylor’s hypothesis approach

    International Nuclear Information System (INIS)

    De Kat, R; Ganapathisubramani, B

    2013-01-01

    Taylor’s hypothesis is often applied in turbulent flow analysis to map temporal information into spatial information. Recent efforts in deriving pressure from particle image velocimetry (PIV) have proposed multiple approaches, each with its own weakness and strength. Application of Taylor’s hypothesis allows us to counter the weakness of an Eulerian approach that is described by de Kat and van Oudheusden (2012 Exp. Fluids 52 1089–106). Two different approaches of using Taylor’s hypothesis in determining planar pressure are investigated: one where pressure is determined from volumetric PIV data and one where pressure is determined from time-resolved stereoscopic PIV data. A performance assessment on synthetic data shows that application of Taylor’s hypothesis can improve determination of pressure from PIV data significantly compared with a time-resolved volumetric approach. The technique is then applied to time-resolved PIV data taken in a cross-flow plane of a turbulent jet (Ganapathisubramani et al 2007 Exp. Fluids 42 923–39). Results appear to indicate that pressure can indeed be obtained from PIV data in turbulent convective flows using the Taylor’s hypothesis approach, where there are no other methods to determine pressure. The role of convection velocity in determination of pressure is also discussed. (paper)

  12. Particle image velocimetry (PIV) study of rotating cylindrical filters for animal cell perfusion processes.

    Science.gov (United States)

    Figueredo-Cardero, Alvio; Chico, Ernesto; Castilho, Leda; de Andrade Medronho, Ricardo

    2012-01-01

    In the present work, the main fluid flow features inside a rotating cylindrical filtration (RCF) system used as external cell retention device for animal cell perfusion processes were investigated using particle image velocimetry (PIV). The motivation behind this work was to provide experimental fluid dynamic data for such turbulent flow using a high-permeability filter, given the lack of information about this system in the literature. The results shown herein gave evidence that, at the boundary between the filter mesh and the fluid, a slip velocity condition in the tangential direction does exist, which had not been reported in the literature so far. In the RCF system tested, this accounted for a fluid velocity 10% lower than that of the filter tip, which could be important for the cake formation kinetics during filtration. Evidence confirming the existence of Taylor vortices under conditions of turbulent flow and high permeability, typical of animal cell perfusion RCF systems, was obtained. Second-order turbulence statistics were successfully calculated. The radial behavior of the second-order turbulent moments revealed that turbulence in this system is highly anisotropic, which is relevant for performing numerical simulations of this system. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

  13. Microparticle image velocimetry approach to flow measurements in isolated contracting lymphatic vessels.

    Science.gov (United States)

    Margaris, Konstantinos N; Nepiyushchikh, Zhanna; Zawieja, David C; Moore, James; Black, Richard A

    2016-02-01

    We describe the development of an optical flow visualization method for resolving the flow velocity vector field in lymphatic vessels in vitro. The aim is to develop an experimental protocol for accurately estimating flow parameters, such as flow rate and shear stresses, with high spatial and temporal resolution. Previous studies in situ have relied on lymphocytes as tracers, but their low density resulted in a reduced spatial resolution whereas the assumption that the flow was fully developed in order to determine the flow parameters of interest may not be valid, especially in the vicinity of the valves, where the flow is undoubtedly more complex. To overcome these issues, we have applied the time-resolved microparticle image velocimetry (μ -PIV) technique, a well-established method that can provide increased spatial and temporal resolution that this transient flow demands. To that end, we have developed a custom light source, utilizing high-power light-emitting diodes, and associated control and image processing software. This paper reports the performance of the system and the results of a series of preliminary experiments performed on vessels isolated from rat mesenteries, demonstrating, for the first time, the successful application of the μ -PIV technique in these vessels.

  14. Development of a compact x-ray particle image velocimetry for measuring opaque flows.

    Science.gov (United States)

    Lee, Sang Joon; Kim, Guk Bae; Yim, Dae Hyun; Jung, Sung Yong

    2009-03-01

    A compact x-ray particle image velocimetry (PIV) system employing a medical x-ray tube as a light source was developed to measure quantitative velocity field information of opaque flows. The x-ray PIV system consists of a medical x-ray tube, an x-ray charge coupled device camera, a programmable shutter for a pulse-type x ray, and a synchronization device. Through performance tests, the feasibility of the developed x-ray PIV system as a flow measuring device was verified. To check the feasibility of the developed system, we tested a tube flow at two different mean velocities of 1 and 2 mm/s. The x-ray absorption of tracer particles must be quite different from that of working fluid to have a good contrast in x-ray images. All experiments were performed under atmospheric pressure condition. This system is unique and useful for investigating various opaque flows or flows inside opaque conduits.

  15. Investigation of the hydrodynamic behavior of diatom aggregates using particle image velocimetry.

    Science.gov (United States)

    Xiao, Feng; Li, Xiaoyan; Lam, Kitming; Wang, Dongsheng

    2012-01-01

    The hydrodynamic behavior of diatom aggregates has a significant influence on the interactions and flocculation kinetics of algae. However, characterization of the hydrodynamics of diatoms and diatom aggregates in water is rather difficult. In this laboratory study, an advanced visualization technique in particle image velocimetry (PIV) was employed to investigate the hydrodynamic properties of settling diatom aggregates. The experiments were conducted in a settling column filled with a suspension of fluorescent polymeric beads as seed tracers. A laser light sheet was generated by the PIV setup to illuminate a thin vertical planar region in the settling column, while the motions of particles were recorded by a high speed charge-coupled device (CCD) camera. This technique was able to capture the trajectories of the tracers when a diatom aggregate settled through the tracer suspension. The PIV results indicated directly the curvilinear feature of the streamlines around diatom aggregates. The rectilinear collision model largely overestimated the collision areas of the settling particles. Algae aggregates appeared to be highly porous and fractal, which allowed streamlines to penetrate into the aggregate interior. The diatom aggregates have a fluid collection efficiency of 10%-40%. The permeable feature of aggregates can significantly enhance the collisions and flocculation between the aggregates and other small particles including algal cells in water.

  16. Flow visualization through particle image velocimetry in realistic model of rhesus monkey's upper airway.

    Science.gov (United States)

    Kim, Ji-Woong; Phuong, Nguyen Lu; Aramaki, Shin-Ichiro; Ito, Kazuhide

    2018-05-01

    Studies concerning inhalation toxicology and respiratory drug-delivery systems require biological testing involving experiments performed on animals. Particle image velocimetry (PIV) is an effective in vitro technique that reveals detailed inhalation flow patterns, thereby assisting analyses of inhalation exposure to various substances. A realistic model of a rhesus-monkey upper airway was developed to investigate flow patterns in its oral and nasal cavities through PIV experiments performed under steady-state constant inhalation conditions at various flow rates-4, 10, and 20 L/min. Flow rate of the fluid passing through the inlet into the trachea was measured to obtain characteristic flow mechanisms, and flow phenomena in the model were confirmed via characterized flow fields. It was observed that increase in flow rate leads to constant velocity profiles in upper and lower trachea regions. It is expected that the results of this study would contribute to future validation of studies aimed at developing in silico models, especially those involving computational fluid dynamic (CFD) analysis. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Development of a compact x-ray particle image velocimetry for measuring opaque flows

    International Nuclear Information System (INIS)

    Lee, Sang Joon; Kim, Guk Bae; Yim, Dae Hyun; Jung, Sung Yong

    2009-01-01

    A compact x-ray particle image velocimetry (PIV) system employing a medical x-ray tube as a light source was developed to measure quantitative velocity field information of opaque flows. The x-ray PIV system consists of a medical x-ray tube, an x-ray charge coupled device camera, a programmable shutter for a pulse-type x ray, and a synchronization device. Through performance tests, the feasibility of the developed x-ray PIV system as a flow measuring device was verified. To check the feasibility of the developed system, we tested a tube flow at two different mean velocities of 1 and 2 mm/s. The x-ray absorption of tracer particles must be quite different from that of working fluid to have a good contrast in x-ray images. All experiments were performed under atmospheric pressure condition. This system is unique and useful for investigating various opaque flows or flows inside opaque conduits.

  18. Particle image velocimetry measurements in an anatomical vascular model fabricated using inkjet 3D printing

    Science.gov (United States)

    Aycock, Kenneth I.; Hariharan, Prasanna; Craven, Brent A.

    2017-11-01

    For decades, the study of biomedical fluid dynamics using optical flow visualization and measurement techniques has been limited by the inability to fabricate transparent physical models that realistically replicate the complex morphology of biological lumens. In this study, we present an approach for producing optically transparent anatomical models that are suitable for particle image velocimetry (PIV) using a common 3D inkjet printing process (PolyJet) and stock resin (VeroClear). By matching the index of refraction of the VeroClear material using a room-temperature mixture of water, sodium iodide, and glycerol, and by printing the part in an orientation such that the flat, optical surfaces are at an approximately 45° angle to the build plane, we overcome the challenges associated with using this 3D printing technique for PIV. Here, we summarize our methodology and demonstrate the process and the resultant PIV measurements of flow in an optically transparent anatomical model of the human inferior vena cava.

  19. Investigation and visualization of internal flow through particle aggregates and microbial flocs using particle image velocimetry.

    Science.gov (United States)

    Xiao, Feng; Lam, Kit Ming; Li, Xiao-yan

    2013-05-01

    An advanced particle-tracking and flow-visualization technology, particle image velocimetry (PIV), was utilized to investigate the hydrodynamic properties of large aggregates in water. The laser-based PIV system was used together with a settling column to capture the streamlines around two types of aggregates: latex particle aggregates and activated sludge (AS) flocs. Both types of the aggregates were highly porous and fractal with fractal dimensions of 2.13±0.31 for the latex particle aggregates (1210-2144 μm) and 1.78±0.24 for the AS flocs (1265-3737 μm). The results show that PIV is a powerful flow visualization technique capable of determining flow field details at the micrometer scale around and through settling aggregates and flocs. The PIV streamlines provided direct experimental proof of internal flow through the aggregate interiors. According to the PIV images, fluid collection efficiency ranged from 0.052 to 0.174 for the latex particle aggregates and from 0.008 to 0.126 for AS flocs. AS flocs are apparently less permeable than the particle aggregates, probably due to the extracellular polymeric substances (EPSs) produced by bacteria clogging the pores within the flocs. The internal permeation of fractal aggregates and bio-flocs would enhance flocculation between particles and material transport into the aggregates. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Sadhana | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Author Affiliations. Miriam Petitti1 Antonello A Barresi1 Daniele L Marchisio1. Dipartimento di Scienza Applicata e Tecnologia, Istituto di Ing. Chimica, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italia ...

  1. Avaliação do bem-estar fetal pela dopplervelocimetria com mapeamento em cores Evaluation of fetal well-being through color doppler velocimetry

    Directory of Open Access Journals (Sweden)

    Cleide Mara Mazzotti de Oliveira Franzin

    1999-01-01

    Full Text Available Objetivos: Avaliar a eficiência do exame dopplervelocimétrico no diagnóstico do bem-estar fetal. Metodologia: Foram analisadas 130 gestantes atendidas no Serviço de Ultra-Sonografia do Centro de Atenção Integral à Saúde da Mulher da Universidade Estadual de Campinas, entre a 28ª e a 42ª semana. Foram feitas correlações entre o Doppler das artérias umbilical, cerebral média e aorta abdominal fetal com os resultados perinatais adversos. As gestantes selecionadas para o estudo foram submetidas eletivamente ao parto cesáreo, no máximo quatro horas após o exame Doppler. Considerou-se como resultados perinatais adversos: índice de Apgar ao 5º minuto menor que sete, internação em unidade de terapia intensiva neonatal, retardo de crescimento intra-uterino, sofrimento fetal agudo, mortalidade perinatal, hipoglicemia, enterocolite necrosante e hemorragia cerebral. Os índices de impedância das artérias umbilical, cerebral média e aorta abdominal foram relacionados caso a caso com os resultados perinatais adversos. Resultados: a relação sístole/diástole da artéria umbilical apresentou maior sensibilidade (80,76% do que o índice de pulsatilidade e índice de resistência da artéria umbilical. O estudo Doppler da artéria umbilical apresentou melhor sensibilidade que o da artéria cerebral média e da aorta abdominal na detecção de resultados perinatais adversos. Conclusão: a dopplervelocimetria das artérias umbilical e cerebral média apresentou boa capacidade de avaliação do bem-estar fetal e associação significativa com resultados perinatais adversos.Purpose: to evaluate the accuracy of Doppler velocimetry in the diagnosis of fetal well-being. Methods: a total of 130 pregnant women assisted at the Ultrasound Unit of the Center for Integral Assistance of Women's Health, UNICAMP, between the 28th and 42nd gestational weeks was analyzed. The correlation between fetal umbilical and middle cerebral arteries, abdominal

  2. Kriptosporidiosis di Indonesia

    Directory of Open Access Journals (Sweden)

    Tri Wijayanti

    2017-07-01

    Full Text Available ABSTRACTCryptosporidiosis included to waterborne and soil transmited diseases, caused by Cryptosporidium, obligat intraceluller pathogen organism. Cryptosporidium cause intestinal infection of human and animal acute diarrhea. Lung cryptosporidiosis on HIV/AIDS and tuberculosis  patients was reported. Diarrhea still be important health problem because diarrhea was be the third dominant contributor of children morbidity and mortality at some country include Indonesia. Every children have 1,6-2x diarrhea onset annually. Diarrhea cases caused by Cryptosporidium sp parasite was around 4-11%. Focus of this review is  about cryptosporidiosis on children, HIV/AIDS and tuberculosis patients, animal, environment, diagnostic and it’s prevention and control. Cryptosporidium species confirmed in Indonesia are C. wrairi, C. muris,  C. felis, C. hominis, C. meleagridis and C. parvum, indicated that there was a big rule of animal on Cryptosporidium transmission. Cryptosporidium was necessary to be one of diseases diagnose on HIV/AIDS and tuberculosis patients. Transmission of Cryptosporidium by  respiratory secretion (droplet, aerosol or contact with vomiting must be anticipated to prevent cryptosporidiosis especially on imunocompromissed/imunodeficiency people. Rapid Diagnostic Test that have highly sensitivity and spesificity is very important on Cryptosporidium cases finding and surveillance in Indonesia. Environment and cattle sanitation, personal hygiene, water and food treatment, is necessary to prevent cryptosporidiosis transmission.  Kriptosporidiosis termasuk waterborne dan soil transmitted diseases, disebabkan oleh Cryptosporidium yang bersifat obligat intraseluler. Cryptosporidium menyebabkan infeksi pada usus halus dan dapat menyebabkan diare akut pada manusia dan hewan. Kriptosporidiosis paru telah dilaporkan pada penderita HIV/AIDS dan tuberkulosis. Diare merupakan penyumbang utama ketiga angka kesakitan dan kematian anak di berbagai negara

  3. PhD Dissertations Tesi di dottorato

    Directory of Open Access Journals (Sweden)

    Redazione Reti Medievali (a cura di

    2005-12-01

    Full Text Available Report of PhD Dissertations.Anna Airò La scrittura delle regole. Politica e istituzioni a Taranto nel Quattrocento, Tesi di dottorato di ricerca in Storia medievale, Università degli studi di Firenze, 2005 Pasquale Arfé La Clavis Physicae II (316-529 di Honorius Augustodunensis. Studio ed edizione critica, Tesi di dottorato in Storia della filosofia medievale, Università degli Studi di Napoli "L'Orientale", 2005 Alessandro Azzimonti Scrittura agiografica e strutture di potere nell'Italia centro-settentrionale (X-XII secolo, Tesi di dottorato di ricerca in Forme del sapere storico dal medioevo alla contemporaneità, Università degli Studi di Trieste, 2004 Domenico Cerami Il "Confine conteso". Uomini, istituzioni, culture a Monteveglio tra VIII-XII secolo, Tesi di dottorato di ricerca in Storia Medievale, Università degli studi di Bologna, 2005 Federica Chilà Ostaggi. Uno strumento di pacificazione e governo tra i secoli VIII e XII, Tesi di dottorato di ricerca in Istituzioni, società, religioni dal Tardo Antico alla fine del Medioevo, Università degli Studi di Torino, 2004 Enrico Faini Firenze nei secoli X-XIII: economia e società, Tesi di dottorato di ricerca in Storia medievale, Università degli studi di Firenze, 2005Alessio FioreStrutture e pratiche del potere signorile in area umbro-marchigiana (secoli XI-XIII, Tesi di dottorato ricerca in Storia, Università degli studi di Pisa, 2004Giampaolo FrancesconiTra Riforma, vescovo e clientes. Camaldoli e le società locali (secoli XI-XIII, Tesi di dottorato di ricerca in Storia medievale, Università degli studi di Firenze, 2005 [09/05] Giuseppe Gardoni "Episcopus et potestas". Vescovi e società a Mantova nella prima metà del Duecento, Tesi di dottorato di ricerca in Storia del Cristianesimo e delle Chiese (antichità, medioevo, età moderna, Università degli Studi di Padova, 2005 Nicola Mancassola La gestione delle campagne tra Langobardia e Romània in età carolingia e post

  4. Esercizi di fisica meccanica e termodinamica

    CERN Document Server

    Dalba, G

    2006-01-01

    La risoluzione di esercizi rappresenta uno strumento indispensabile per raggiungere una comprensione sicura e approfondita dei concetti di Fisica appresi dai corsi e dai testi di teoria. Frutto di una lunga esperienza didattica dei due autori nell'insegnamento universitario della meccanica e della termodinamica, questa raccolta contiene 188 esercizi, di cui 91 completamente risolti ed accompagnati da un ampio corredo di figure. Il peimo capitolo presenta un'introduzione ai sistemi di unità di misura, al calcolo dimensionale, all'uso corretto delle cifre significative e degli arrotondamenti, ai grafici. Gli altri capitoli contengono gli esercizi, suddivisi per argomento e preceduti da una serie di paragrafi riassuntivi dei concetti fondamentali. Criterio ispiratore di questo lavoro è l'adozione di una metodologia per la soluzione degli esercizi basata sempre sull'analisi accurata dei dati a disposizione e sul riferimento ai principi e alle leggi della Fisica, mai alla sola intuizione.

  5. Sistemi tecnologici innovativi di involucro per il recupero del patrimonio edilizio recente. L'edilizia scolastica nel Comune di Bologna

    OpenAIRE

    Mazzoli, Cecilia

    2015-01-01

    La ricerca è volta a presentare un nuovo approccio integrato, a supporto di operatori e progettisti, per la gestione dell’intero processo progettuale di interventi di riqualificazione energetica e architettonica del patrimonio edilizio recente, mediante l’impiego di soluzioni tecnologiche innovative di involucro edilizio. Lo studio richiede necessariamente l’acquisizione di un repertorio selezionato di sistemi costruttivi di involucro, come base di partenza per l’elaborazione di soluzioni ...

  6. Study of Fish Response Using Particle Image Velocimetry and High-Speed, High-Resolution Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Zhiqun; Richmond, Marshall C.; Guensch, Gregory R.; Mueller, Robert P.

    2004-10-23

    Existing literature of previous particle image velocimetry (PIV) studies of fish swimming has been reviewed. Historically, most of the studies focused on the performance evaluation of freely swimming fish. Technological advances over the last decade, especially the development of digital particle image velocimetry (DPIV) technique, make possible more accurate, quantitative descriptions of the flow patterns adjacent to the fish and in the wake behind the fins and tail, which are imperative to decode the mechanisms of drag reduction and propulsive efficiency. For flows generated by different organisms, the related scales and flow regimes vary significantly. For small Reynolds numbers, viscosity dominates; for very high Reynolds numbers, inertia dominates, and three-dimensional complexity occurs. The majority of previous investigations dealt with the lower end of Reynolds number range. The fish of our interest, such as rainbow trout and spring and fall chinook salmon, fall into the middle range, in which neither viscosity nor inertia is negligible, and three-dimensionality has yet to dominate. Feasibility tests have proven the applicability of PIV to flows around fish. These tests have shown unsteady vortex shedding in the wake, high vorticity region and high stress region, with the highest in the pectoral area. This evident supports the observations by Nietzel et al. (2000) and Deng et al. (2004) that the operculum are most vulnerable to damage from the turbulent shear flow, because they are easily pried open, and the large vorticity and shear stress can lift and tear off scales, rupture or dislodge eyes, and damage gills. In addition, the unsteady behavior of the vortex shedding in the wake implies that injury to fish by the instantaneous flow structures would likely be much higher than the injury level estimated using the average values of the dynamics parameters. Based on existing literature, our technological capability, and relevance and practicability to

  7. Particle image velocimetry correlation signal-to-noise ratio metrics and measurement uncertainty quantification

    International Nuclear Information System (INIS)

    Xue, Zhenyu; Charonko, John J; Vlachos, Pavlos P

    2014-01-01

    In particle image velocimetry (PIV) the measurement signal is contained in the recorded intensity of the particle image pattern superimposed on a variety of noise sources. The signal-to-noise-ratio (SNR) strength governs the resulting PIV cross correlation and ultimately the accuracy and uncertainty of the resulting PIV measurement. Hence we posit that correlation SNR metrics calculated from the correlation plane can be used to quantify the quality of the correlation and the resulting uncertainty of an individual measurement. In this paper we extend the original work by Charonko and Vlachos and present a framework for evaluating the correlation SNR using a set of different metrics, which in turn are used to develop models for uncertainty estimation. Several corrections have been applied in this work. The SNR metrics and corresponding models presented herein are expanded to be applicable to both standard and filtered correlations by applying a subtraction of the minimum correlation value to remove the effect of the background image noise. In addition, the notion of a ‘valid’ measurement is redefined with respect to the correlation peak width in order to be consistent with uncertainty quantification principles and distinct from an ‘outlier’ measurement. Finally the type and significance of the error distribution function is investigated. These advancements lead to more robust and reliable uncertainty estimation models compared with the original work by Charonko and Vlachos. The models are tested against both synthetic benchmark data as well as experimental measurements. In this work, U 68.5 uncertainties are estimated at the 68.5% confidence level while U 95 uncertainties are estimated at 95% confidence level. For all cases the resulting calculated coverage factors approximate the expected theoretical confidence intervals, thus demonstrating the applicability of these new models for estimation of uncertainty for individual PIV measurements. (paper)

  8. Numerical and experimental study on vorticity measurement in liquid metal using local Lorentz force velocimetry

    Science.gov (United States)

    Hernández, Daniel; Marangoni, Rafael; Schleichert, Jan; Karcher, Christian; Fröhlich, Thomas; Wondrak, Thomas

    2018-03-01

    Local Lorentz force velocimetry (local LFV) is a contactless velocity measurement technique for liquid metals. Due to the relative movement between an electrically conductive fluid and a static applied magnetic field, eddy currents and a flow-braking Lorentz force are generated inside the metal melt. This force is proportional to the flow rate or to the local velocity, depending on the volume subset of the flow spanned by the magnetic field. By using small-size magnets, a localized magnetic field distribution is achieved allowing a local velocity assessment in the region adjacent to the wall. In the present study, we describe a numerical model of our experiments at a continuous caster model where the working fluid is GaInSn in eutectic composition. Our main goal is to demonstrate that this electromagnetic technique can be applied to measure vorticity distributions, i.e. to resolve velocity gradients as well. Our results show that by using a cross-shaped magnet system, the magnitude of the torque perpendicular to the surface of the mold significantly increases improving its measurement in a liquid metal flow. According to our numerical model, this torque correlates with the vorticity of the velocity in this direction. Before validating our numerical predictions, an electromagnetic dry calibration of the measurement system composed of a multicomponent force and torque sensor and a cross-shaped magnet was done using a rotating disk made of aluminum. The sensor is able to measure simultaneously all three components of force and torque, respectively. This calibration step cannot be avoided and it is used for an accurate definition of the center of the magnet with respect to the sensor’s coordinate system for torque measurements. Finally, we present the results of the experiments at the mini-LIMMCAST facility showing a good agreement with the numerical model.

  9. Numerical and experimental study of the effect of the induced electric potential in Lorentz force velocimetry

    Science.gov (United States)

    Hernández, Daniel; Boeck, Thomas; Karcher, Christian; Wondrak, Thomas

    2018-01-01

    Lorentz force velocimetry (LFV) is a contactless velocity measurement technique for electrically conducting fluids. When a liquid metal or a molten glass flows through an externally applied magnetic field, eddy currents and a flow-braking force are generated inside the liquid. This force is proportional to the velocity or flow rate of the fluid and, due to Newton’s third law, a force of the same magnitude but in opposite direction acts on the source of the applied magnetic field which in our case are permanent magnets. According to Ohm’s law for moving conductors at low magnetic Reynolds numbers, an electric potential is induced which ensures charge conservation. In this paper, we analyze the contribution of the induced electric potential to the total Lorentz force by considering two different scenarios: conducting walls of finite thickness and aspect ratio variation of the cross-section of the flow. In both the cases, the force component generated by the electric potential is always in the opposite direction to the total Lorentz force. This force component is sensitive to the electric boundary conditions of the flow of which insulating and perfectly conducting walls are the two limiting cases. In the latter case, the overall electric resistance of the system is minimized, resulting in a considerable increase in the measured Lorentz force. Additionally, this force originating from the electric potential also decays when the aspect ratio of the cross-section of the flow is changed. Hence, the sensitivity of the measurement technique is enhanced by either increasing wall conductivity or optimizing the aspect ratio of the cross-section of the flow.

  10. Displacement fields from point cloud data: Application of particle imaging velocimetry to landslide geodesy

    Science.gov (United States)

    Aryal, Arjun; Brooks, Benjamin A.; Reid, Mark E.; Bawden, Gerald W.; Pawlak, Geno

    2012-01-01

    Acquiring spatially continuous ground-surface displacement fields from Terrestrial Laser Scanners (TLS) will allow better understanding of the physical processes governing landslide motion at detailed spatial and temporal scales. Problems arise, however, when estimating continuous displacement fields from TLS point-clouds because reflecting points from sequential scans of moving ground are not defined uniquely, thus repeat TLS surveys typically do not track individual reflectors. Here, we implemented the cross-correlation-based Particle Image Velocimetry (PIV) method to derive a surface deformation field using TLS point-cloud data. We estimated associated errors using the shape of the cross-correlation function and tested the method's performance with synthetic displacements applied to a TLS point cloud. We applied the method to the toe of the episodically active Cleveland Corral Landslide in northern California using TLS data acquired in June 2005–January 2007 and January–May 2010. Estimated displacements ranged from decimeters to several meters and they agreed well with independent measurements at better than 9% root mean squared (RMS) error. For each of the time periods, the method provided a smooth, nearly continuous displacement field that coincides with independently mapped boundaries of the slide and permits further kinematic and mechanical inference. For the 2010 data set, for instance, the PIV-derived displacement field identified a diffuse zone of displacement that preceded by over a month the development of a new lateral shear zone. Additionally, the upslope and downslope displacement gradients delineated by the dense PIV field elucidated the non-rigid behavior of the slide.

  11. Multiparticle imaging technique for two-phase fluid flows using pulsed laser speckle velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, T.A.

    1992-12-01

    The practical use of Pulsed Laser Velocimetry (PLV) requires the use of fast, reliable computer-based methods for tracking numerous particles suspended in a fluid flow. Two methods for performing tracking are presented. One method tracks a particle through multiple sequential images (minimum of four required) by prediction and verification of particle displacement and direction. The other method, requiring only two sequential images uses a dynamic, binary, spatial, cross-correlation technique. The algorithms are tested on computer-generated synthetic data and experimental data which was obtained with traditional PLV methods. This allowed error analysis and testing of the algorithms on real engineering flows. A novel method is proposed which eliminates tedious, undersirable, manual, operator assistance in removing erroneous vectors. This method uses an iterative process involving an interpolated field produced from the most reliable vectors. Methods are developed to allow fast analysis and presentation of sets of PLV image data. Experimental investigation of a two-phase, horizontal, stratified, flow regime was performed to determine the interface drag force, and correspondingly, the drag coefficient. A horizontal, stratified flow test facility using water and air was constructed to allow interface shear measurements with PLV techniques. The experimentally obtained local drag measurements were compared with theoretical results given by conventional interfacial drag theory. Close agreement was shown when local conditions near the interface were similar to space-averaged conditions. However, theory based on macroscopic, space-averaged flow behavior was shown to give incorrect results if the local gas velocity near the interface as unstable, transient, and dissimilar from the average gas velocity through the test facility.

  12. Smooth- and rough-wall boundary layer structure from high spatial range particle image velocimetry

    Science.gov (United States)

    Squire, D. T.; Morrill-Winter, C.; Hutchins, N.; Marusic, I.; Schultz, M. P.; Klewicki, J. C.

    2016-10-01

    Two particle image velocimetry arrangements are used to make true spatial comparisons between smooth- and rough-wall boundary layers at high Reynolds numbers across a very wide range of streamwise scales. Together, the arrangements resolve scales ranging from motions on the order of the Kolmogorov microscale to those longer than twice the boundary layer thickness. The rough-wall experiments were obtained above a continuous sandpaper sheet, identical to that used by Squire et al. [J. Fluid Mech. 795, 210 (2016), 10.1017/jfm.2016.196], and cover a range of friction and equivalent sand-grain roughness Reynolds numbers (12 000 ≲δ+≲ 18000, 62 ≲ks+≲104 ). The smooth-wall experiments comprise new and previously published data spanning 6500 ≲δ+≲17 000 . Flow statistics from all experiments show similar Reynolds number trends and behaviors to recent, well-resolved hot-wire anemometry measurements above the same rough surface. Comparisons, at matched δ+, between smooth- and rough-wall two-point correlation maps and two-point magnitude-squared coherence maps demonstrate that spatially the outer region of the boundary layer is the same between the two flows. This is apparently true even at wall-normal locations where the total (inner-normalized) energy differs between the smooth and rough wall. Generally, the present results provide strong support for Townsend's [The Structure of Turbulent Shear Flow (Cambridge University Press, Cambridge, 1956), Vol. 1] wall-similarity hypothesis in high Reynolds number fully rough boundary layer flows.

  13. Hypersonic Boundary Layer Measurements with Variable Blowing Rates Using Molecular Tagging Velocimetry

    Science.gov (United States)

    Bathel, Brett F.; Danehy, Paul M.; Johansen, Craig T.; Jones, Stephen B.; Goyne, Christopher P.

    2012-01-01

    Measurements of mean and instantaneous streamwise velocity profiles in a hypersonic boundary layer with variable rates of mass injection (blowing) of nitrogen dioxide (NO2) were obtained over a 10-degree half-angle wedge model. The NO2 was seeded into the flow from a slot located 29.4 mm downstream of the sharp leading edge. The top surface of the wedge was oriented at a 20 degree angle in the Mach 10 flow, yielding an edge Mach number of approximately 4.2. The streamwise velocity profiles and streamwise fluctuating velocity component profiles were obtained using a three-laser NO2->NO photolysis molecular tagging velocimetry method. Observed trends in the mean streamwise velocity profiles and profiles of the fluctuating component of streamwise velocity as functions of the blowing rate are described. An effort is made to distinguish between the effect of blowing rate and wall temperature on the measured profiles. An analysis of the mean velocity profiles for a constant blowing rate is presented to determine the uncertainty in the measurement for different probe laser delay settings. Measurements of streamwise velocity were made to within approximately 120 gm of the model surface. The streamwise spatial resolution in this experiment ranged from 0.6 mm to 2.6 mm. An improvement in the spatial precision of the measurement technique has been made, with spatial uncertainties reduced by about a factor of 2 compared to previous measurements. For the quiescent flow calibration measurements presented, uncertainties as low as 2 m/s are obtained at 95% confidence for long delay times (25 gs). For the velocity measurements obtained with the wind tunnel operating, average single-shot uncertainties of less than 44 m/s are obtained at 95% confidence with a probe laser delay setting of 1 gs. The measurements were performed in the 31-inch Mach 10 Air Tunnel at the NASA Langley Research Center.

  14. Trip-Induced Transition Measurements in a Hypersonic Boundary Layer Using Molecular Tagging Velocimetry

    Science.gov (United States)

    Bathel, Brett F.; Danehy, Paul M.; Jones, Stephen B.; Johansen, Craig T.; Goyne, Christopher P.

    2013-01-01

    Measurements of mean streamwise velocity, fluctuating streamwise velocity, and instantaneous streamwise velocity profiles in a hypersonic boundary layer were obtained over a 10-degree half-angle wedge model. A laser-induced fluorescence-based molecular tagging velocimetry technique was used to make the measurements. The nominal edge Mach number was 4.2. Velocity profiles were measured both in an untripped boundary layer and in the wake of a 4-mm diameter cylindrical tripping element centered 75.4 mm downstream of the sharp leading edge. Three different trip heights were investigated: k = 0.53 mm, k = 1.0 mm and k = 2.0 mm. The laminar boundary layer thickness at the position of the measurements was approximately 1 mm, though the exact thickness was dependent on Reynolds number and wall temperature. All of the measurements were made starting from a streamwise location approximately 18 mm downstream of the tripping element. This measurement region continued approximately 30 mm in the streamwise direction. Additionally, measurements were made at several spanwise locations. An analysis of flow features show how the magnitude, spatial location, and spatial growth of streamwise velocity instabilities are affected by parameters such as the ratio of trip height to boundary layer thickness and roughness Reynolds number. The fluctuating component of streamwise velocity measured along the centerline of the model increased from approximately 75 m/s with no trip to +/-225 m/s with a 0.53-mm trip, and to +/-240 m/s with a 1-mm trip, while holding the freestream Reynolds number constant. These measurements were performed in the 31-inch Mach 10 Air Tunnel at the NASA Langley Research Center.

  15. Track benchmarking method for uncertainty quantification of particle tracking velocimetry interpolations

    International Nuclear Information System (INIS)

    Schneiders, Jan F G; Sciacchitano, Andrea

    2017-01-01

    The track benchmarking method (TBM) is proposed for uncertainty quantification of particle tracking velocimetry (PTV) data mapped onto a regular grid. The method provides statistical uncertainty for a velocity time-series and can in addition be used to obtain instantaneous uncertainty at increased computational cost. Interpolation techniques are typically used to map velocity data from scattered PTV (e.g. tomographic PTV and Shake-the-Box) measurements onto a Cartesian grid. Recent examples of these techniques are the FlowFit and VIC+  methods. The TBM approach estimates the random uncertainty in dense velocity fields by performing the velocity interpolation using a subset of typically 95% of the particle tracks and by considering the remaining tracks as an independent benchmarking reference. In addition, also a bias introduced by the interpolation technique is identified. The numerical assessment shows that the approach is accurate when particle trajectories are measured over an extended number of snapshots, typically on the order of 10. When only short particle tracks are available, the TBM estimate overestimates the measurement error. A correction to TBM is proposed and assessed to compensate for this overestimation. The experimental assessment considers the case of a jet flow, processed both by tomographic PIV and by VIC+. The uncertainty obtained by TBM provides a quantitative evaluation of the measurement accuracy and precision and highlights the regions of high error by means of bias and random uncertainty maps. In this way, it is possible to quantify the uncertainty reduction achieved by advanced interpolation algorithms with respect to standard correlation-based tomographic PIV. The use of TBM for uncertainty quantification and comparison of different processing techniques is demonstrated. (paper)

  16. Radial basis function interpolation of unstructured, three-dimensional, volumetric particle tracking velocimetry data

    International Nuclear Information System (INIS)

    Casa, L D C; Krueger, P S

    2013-01-01

    Unstructured three-dimensional fluid velocity data were interpolated using Gaussian radial basis function (RBF) interpolation. Data were generated to imitate the spatial resolution and experimental uncertainty of a typical implementation of defocusing digital particle image velocimetry. The velocity field associated with a steadily rotating infinite plate was simulated to provide a bounded, fully three-dimensional analytical solution of the Navier–Stokes equations, allowing for robust analysis of the interpolation accuracy. The spatial resolution of the data (i.e. particle density) and the number of RBFs were varied in order to assess the requirements for accurate interpolation. Interpolation constraints, including boundary conditions and continuity, were included in the error metric used for the least-squares minimization that determines the interpolation parameters to explore methods for improving RBF interpolation results. Even spacing and logarithmic spacing of RBF locations were also investigated. Interpolation accuracy was assessed using the velocity field, divergence of the velocity field, and viscous torque on the rotating boundary. The results suggest that for the present implementation, RBF spacing of 0.28 times the boundary layer thickness is sufficient for accurate interpolation, though theoretical error analysis suggests that improved RBF positioning may yield more accurate results. All RBF interpolation results were compared to standard Gaussian weighting and Taylor expansion interpolation methods. Results showed that RBF interpolation improves interpolation results compared to the Taylor expansion method by 60% to 90% based on the average squared velocity error and provides comparable velocity results to Gaussian weighted interpolation in terms of velocity error. RMS accuracy of the flow field divergence was one to two orders of magnitude better for the RBF interpolation compared to the other two methods. RBF interpolation that was applied to

  17. Particle image velocimetry correlation signal-to-noise ratio metrics and measurement uncertainty quantification

    Science.gov (United States)

    Xue, Zhenyu; Charonko, John J.; Vlachos, Pavlos P.

    2014-11-01

    In particle image velocimetry (PIV) the measurement signal is contained in the recorded intensity of the particle image pattern superimposed on a variety of noise sources. The signal-to-noise-ratio (SNR) strength governs the resulting PIV cross correlation and ultimately the accuracy and uncertainty of the resulting PIV measurement. Hence we posit that correlation SNR metrics calculated from the correlation plane can be used to quantify the quality of the correlation and the resulting uncertainty of an individual measurement. In this paper we extend the original work by Charonko and Vlachos and present a framework for evaluating the correlation SNR using a set of different metrics, which in turn are used to develop models for uncertainty estimation. Several corrections have been applied in this work. The SNR metrics and corresponding models presented herein are expanded to be applicable to both standard and filtered correlations by applying a subtraction of the minimum correlation value to remove the effect of the background image noise. In addition, the notion of a ‘valid’ measurement is redefined with respect to the correlation peak width in order to be consistent with uncertainty quantification principles and distinct from an ‘outlier’ measurement. Finally the type and significance of the error distribution function is investigated. These advancements lead to more robust and reliable uncertainty estimation models compared with the original work by Charonko and Vlachos. The models are tested against both synthetic benchmark data as well as experimental measurements. In this work, {{U}68.5} uncertainties are estimated at the 68.5% confidence level while {{U}95} uncertainties are estimated at 95% confidence level. For all cases the resulting calculated coverage factors approximate the expected theoretical confidence intervals, thus demonstrating the applicability of these new models for estimation of uncertainty for individual PIV measurements.

  18. Simultaneous particle image velocimetry and infrared imagery of microscale breaking waves

    International Nuclear Information System (INIS)

    Siddiqui, M.H. Kamran; Loewen, Mark R.; Richardson, Christine; Asher, William E.; Jessup, Andrew T.

    2001-01-01

    We report the results from a laboratory investigation in which microscale breaking waves were detected using an infrared (IR) imager and two-dimensional (2-D) velocity fields were simultaneously measured using particle image velocimetry (PIV). In addition, the local heat transfer velocity was measured using the controlled flux technique. To the best of our knowledge these are the first measurements of the instantaneous 2-D velocity fields generated beneath microscale breaking waves. Careful measurements of the water surface profile enabled us to make accurate estimates of the near-surface velocities using PIV. Previous experiments have shown that behind the leading edge of a microscale breaker the cool skin layer is disrupted creating a thermal signature in the IR image [Jessup et al., J. Geophys. Res. 102, 23145 (1997)]. The simultaneously sampled IR images and PIV data enabled us to show that these disruptions or wakes are typically produced by a series of vortices that form behind the leading edge of the breaker. When the vortices are first formed they are very strong and coherent but as time passes, and they move from the crest region to the back face of the wave, they become weaker and less coherent. The near-surface vorticity was correlated with both the fractional area coverage of microscale breaking waves and the local heat transfer velocity. The strong correlations provide convincing evidence that the wakes produced by microscale breaking waves are regions of high near-surface vorticity that are in turn responsible for enhancing air-water heat transfer rates

  19. Turbulent Structure of a Simplified Urban Fluid Flow Studied Through Stereoscopic Particle Image Velocimetry

    Science.gov (United States)

    Monnier, Bruno; Goudarzi, Sepehr A.; Vinuesa, Ricardo; Wark, Candace

    2018-02-01

    Stereoscopic particle image velocimetry was used to provide a three-dimensional characterization of the flow around a simplified urban model defined by a 5 by 7 array of blocks, forming four parallel streets, perpendicular to the incoming wind direction corresponding to a zero angle of incidence. Channeling of the flow through the array under consideration was observed, and its effect increased as the incoming wind direction, or angle of incidence ( AOI), was changed from 0° to 15°, 30°, and 45°. The flow between blocks can be divided into two regions: a region of low turbulence kinetic energy (TKE) levels close to the leeward side of the upstream block, and a high TKE area close to the downstream block. The centre of the arch vortex is located in the low TKE area, and two regions of large streamwise velocity fluctuation bound the vortex in the spanwise direction. Moreover, a region of large spanwise velocity fluctuation on the downstream block is found between the vortex legs. Our results indicate that the reorientation of the arch vortex at increasing AOI is produced by the displacement of the different TKE regions and their interaction with the shear layers on the sides and top of the upstream and downstream blocks, respectively. There is also a close connection between the turbulent structure between the blocks and the wind gusts. The correlations among gust components were also studied, and it was found that in the near-wall region of the street the correlations between the streamwise and spanwise gusts R_{uv} were dominant for all four AOI cases. At higher wall-normal positions in the array, the R_{uw} correlation decreased with increasing AOI, whereas the R_{uv} coefficient increased as AOI increased, and at {it{AOI}}=45° all three correlations exhibited relatively high values of around 0.4.

  20. Irrigant flow during photon-induced photoacoustic streaming (PIPS) using Particle Image Velocimetry (PIV).

    Science.gov (United States)

    Koch, Jon D; Jaramillo, David E; DiVito, Enrico; Peters, Ove A

    2016-03-01

    This study aimed to compare fluid movements generated from photon-induced photoacoustic streaming (PIPS) and passive ultrasonic irrigation (PUI). Particle Image Velocimetry (PIV) was performed using 6-μm melamine spheres in water. Measurement areas were 3-mm-long sections of the canal in the coronal, midroot and apical regions for PIPS (erbium/yttrium-aluminium garnet (Er:YAG) laser set at 15 Hz with 20 mJ), or passive ultrasonic irrigation (PUI, non-cutting insert at 30% unit power) was performed in simulated root canals prepared to an apical size #30/0.04 taper. Fluid movement was analysed directly subjacent to the apical ends of ultrasonic insert or fiber optic tips as well as at midroot and apically. During PUI, measured average velocities were around 0.03 m/s in the immediate vicinity of the sides and tip of the ultrasonic file. Speeds decayed to non-measureable values at a distance of about 2 mm from the sides and tip. During PIPS, typical average speeds were about ten times higher than those measured for PUI, and they were measured throughout the length of the canal, at distances up to 20 mm away. PIPS caused higher average fluid speeds when compared to PUI, both close and distant from the instrument. The findings of this study could be relevant to the debriding and disinfecting stage of endodontic therapy. Irrigation enhancement beyond needle irrigation is relevant to more effectively eradicate microorganisms from root canal systems. PIPS may be an alternative approach due to its ability to create high streaming velocities further away from the activation source compared to ultrasonic activation.

  1. In vitro characterization of bicuspid aortic valve hemodynamics using particle image velocimetry.

    Science.gov (United States)

    Saikrishnan, Neelakantan; Yap, Choon-Hwai; Milligan, Nicole C; Vasilyev, Nikolay V; Yoganathan, Ajit P

    2012-08-01

    The congenital bicuspid aortic valve (BAV) is associated with increased leaflet calcification, ascending aortic dilatation, aortic stenosis (AS) and regurgitation (AR). Although underlying genetic factors have been primarily implicated for these complications, the altered mechanical environment of BAVs could potentially accelerate these pathologies. The objective of the current study is to characterize BAV hemodynamics in an in vitro system. Two BAV models of varying stenosis and jet eccentricity and a trileaflet AV (TAV) were constructed from excised porcine AVs. Particle Image Velocimetry (PIV) experiments were conducted at physiological flow and pressure conditions to characterize fluid velocity fields in the aorta and sinus regions, and ensemble averaged Reynolds shear stress and 2D turbulent kinetic energy were calculated for all models. The dynamics of the BAV and TAV models matched the characteristics of these valves which are observed clinically. The eccentric and stenotic BAV showed the strongest systolic jet (V = 4.2 m/s), which impinged on the aortic wall on the non-fused leaflet side, causing a strong vortex in the non-fused leaflet sinus. The magnitudes of TKE and Reynolds stresses in both BAV models were almost twice as large as comparable values for TAV, and these maximum values were primarily concentrated around the central jet through the valve orifice. The in vitro model described here enables detailed characterization of BAV flow characteristics, which is currently challenging in clinical practice. This model can prove to be useful in studying the effects of altered BAV geometry on fluid dynamics in the valve and ascending aorta. These altered flows can be potentially linked to increased calcific responses from the valve endothelium in stenotic and eccentric BAVs, independent of concomitant genetic factors.

  2. Surface pressure and aerodynamic loads determination of a transonic airfoil based on particle image velocimetry

    International Nuclear Information System (INIS)

    Ragni, D; Ashok, A; Van Oudheusden, B W; Scarano, F

    2009-01-01

    The present investigation assesses a procedure to extract the aerodynamic loads and pressure distribution on an airfoil in the transonic flow regime from particle image velocimetry (PIV) measurements. The wind tunnel model is a two-dimensional NACA-0012 airfoil, and the PIV velocity data are used to evaluate pressure fields, whereas lift and drag coefficients are inferred from the evaluation of momentum contour and wake integrals. The PIV-based results are compared to those derived from conventional loads determination procedures involving surface pressure transducers and a wake rake. The method applied in this investigation is an extension to the compressible flow regime of that considered by van Oudheusden et al (2006 Non-intrusive load characterization of an airfoil using PIV Exp. Fluids 40 988–92) at low speed conditions. The application of a high-speed imaging system allows the acquisition in relatively short time of a sufficient ensemble size to compute converged velocity statistics, further translated in turbulent fluctuations included in the pressure and loads calculation, notwithstanding their verified negligible influence in the computation. Measurements are performed at varying spatial resolution to optimize the loads determination in the wake region and around the airfoil, further allowing us to assess the influence of spatial resolution in the proposed procedure. Specific interest is given to the comparisons between the PIV-based method and the conventional procedures for determining the pressure coefficient on the surface, the drag and lift coefficients at different angles of attack. Results are presented for the experiments at a free-stream Mach number M = 0.6, with the angle of attack ranging from 0° to 8°

  3. Estimation of uncertainty bounds for individual particle image velocimetry measurements from cross-correlation peak ratio

    International Nuclear Information System (INIS)

    Charonko, John J; Vlachos, Pavlos P

    2013-01-01

    Numerous studies have established firmly that particle image velocimetry (PIV) is a robust method for non-invasive, quantitative measurements of fluid velocity, and that when carefully conducted, typical measurements can accurately detect displacements in digital images with a resolution well below a single pixel (in some cases well below a hundredth of a pixel). However, to date, these estimates have only been able to provide guidance on the expected error for an average measurement under specific image quality and flow conditions. This paper demonstrates a new method for estimating the uncertainty bounds to within a given confidence interval for a specific, individual measurement. Here, cross-correlation peak ratio, the ratio of primary to secondary peak height, is shown to correlate strongly with the range of observed error values for a given measurement, regardless of flow condition or image quality. This relationship is significantly stronger for phase-only generalized cross-correlation PIV processing, while the standard correlation approach showed weaker performance. Using an analytical model of the relationship derived from synthetic data sets, the uncertainty bounds at a 95% confidence interval are then computed for several artificial and experimental flow fields, and the resulting errors are shown to match closely to the predicted uncertainties. While this method stops short of being able to predict the true error for a given measurement, knowledge of the uncertainty level for a PIV experiment should provide great benefits when applying the results of PIV analysis to engineering design studies and computational fluid dynamics validation efforts. Moreover, this approach is exceptionally simple to implement and requires negligible additional computational cost. (paper)

  4. A three-dimensional strain measurement method in elastic transparent materials using tomographic particle image velocimetry.

    Directory of Open Access Journals (Sweden)

    Azuma Takahashi

    Full Text Available The mechanical interaction between blood vessels and medical devices can induce strains in these vessels. Measuring and understanding these strains is necessary to identify the causes of vascular complications. This study develops a method to measure the three-dimensional (3D distribution of strain using tomographic particle image velocimetry (Tomo-PIV and compares the measurement accuracy with the gauge strain in tensile tests.The test system for measuring 3D strain distribution consists of two cameras, a laser, a universal testing machine, an acrylic chamber with a glycerol water solution for adjusting the refractive index with the silicone, and dumbbell-shaped specimens mixed with fluorescent tracer particles. 3D images of the particles were reconstructed from 2D images using a multiplicative algebraic reconstruction technique (MART and motion tracking enhancement. Distributions of the 3D displacements were calculated using a digital volume correlation. To evaluate the accuracy of the measurement method in terms of particle density and interrogation voxel size, the gauge strain and one of the two cameras for Tomo-PIV were used as a video-extensometer in the tensile test. The results show that the optimal particle density and interrogation voxel size are 0.014 particles per pixel and 40 × 40 × 40 voxels with a 75% overlap. The maximum measurement error was maintained at less than 2.5% in the 4-mm-wide region of the specimen.We successfully developed a method to experimentally measure 3D strain distribution in an elastic silicone material using Tomo-PIV and fluorescent particles. To the best of our knowledge, this is the first report that applies Tomo-PIV to investigate 3D strain measurements in elastic materials with large deformation and validates the measurement accuracy.

  5. Teoria dei quanti di luce

    CERN Document Server

    Einstein, Albert

    1992-01-01

    In questo scritto un’intuizione storica limpida e penetrante, con la quale il giovane Einstein pose le basi per i successivi studi sulla teoria della relatività, è consegnata al lettore in forma chiara ed essenziale. Nel 1905, appena ventiseienne, Einstein intervenne nel dibattito sulle leggi di distribuzione della radiazione luminosa che all’epoca animava gli ambienti scientifici e che si inseriva nel più ampio processo di revisione delle scienze fisiche e naturali. Il giovane scienziato tentò di dimostrare come «...una radiazione monocromatica di densità ridotta... si comporta, per quanto riguarda la termodinamica, come se fosse composta da quanti di energia indipendenti l’uno dall’altro». In altre parole, nel caso limite di basse temperature e piccole lunghezze d’onda, la teoria ondulatoria della luce, tradizionalmente accettata e riconosciuta dai fisici, sembrava destituita di ogni fondamento, e si faceva strada l’ipotesi che la radiazione viaggiasse “a pacchetti”. Lo sviluppo succe...

  6. Compendio di meccanica razionale

    CERN Document Server

    Levi-Civita, Tullio

    1948-01-01

    Questa seconda edizione, pur conforme nel suo complesso alla precedente, ha subìto un'accurata revisione generale e svariati ritocchi particolari. Ci limitiamo qui a rivelare che nella I Parte abbiamo aggiunto un'analisi della nozione di "tempo", diretta a lumeggiare il momento preciso del distacco fra l'impostazione classica della Meccanica e della Fisica e quelle relativistica; e, per quel che concerne la Statica, vi abbiamo inquadrato, senza ammissioni estranee, la determinazione delle reazioni nel cosidetto "arco a tre cerniere" e ridotto a forma didatticamente più semplie ed espressiva il paragrafo sull'"attrito volvente". Nella II Parte abbiamo ulteriormente semplificato la teoria elementare dei "fenomeni giroscopici", seguendo G. Bisconcini.

  7. Force Measurements on Plasma Actuators Using Phase-locked Particle Image Velocimetry

    Science.gov (United States)

    2015-05-01

    structured as follows. In Section 2, the details of the experimental apparatus and procedures, including the plasma actuator, the electronics used for...was placed ing the plasm wire gauge ( tage probe. l, which wa a ratio of 2 on signal wa he excitation ft) and the di DRDC-RDD on the force a...a Trek Mod t 2.5 kHz an e plasma cope (right). 1 a t el d DRDC F Durin using metho magn plasm -RDDC-2015 igure 4: Sche Figu g each exper the

  8. Sardegna chiama Friuli: storia di una cooperazione

    Directory of Open Access Journals (Sweden)

    Sandra Bianchi

    2001-01-01

    Full Text Available Un progetto sperimentale, attuato nella scuola dell'obbligo, in cui l'esperienza di precedenti corsi di formazione a distanza da parte delle due insegnanti coordinatrici del lavoro e l'organizzazione di una virtual classroom si sono coniugate nella realizzazione di "Gli Eroi Dimenticati" e "La Meglio Gioventu'", iniziative prodotte all'interno del piu' ampio progetto di cooperazione telematica "Sardegna Chiama Friuli".

  9. A Mobile System for Measuring Water Surface Velocities Using Unmanned Aerial Vehicle and Large-Scale Particle Image Velocimetry

    Science.gov (United States)

    Chen, Y. L.

    2015-12-01

    Measurement technologies for velocity of river flow are divided into intrusive and nonintrusive methods. Intrusive method requires infield operations. The measuring process of intrusive methods are time consuming, and likely to cause damages of operator and instrument. Nonintrusive methods require fewer operators and can reduce instrument damages from directly attaching to the flow. Nonintrusive measurements may use radar or image velocimetry to measure the velocities at the surface of water flow. The image velocimetry, such as large scale particle image velocimetry (LSPIV) accesses not only the point velocity but the flow velocities in an area simultaneously. Flow properties of an area hold the promise of providing spatially information of flow fields. This study attempts to construct a mobile system UAV-LSPIV by using an unmanned aerial vehicle (UAV) with LSPIV to measure flows in fields. The mobile system consists of a six-rotor UAV helicopter, a Sony nex5T camera, a gimbal, an image transfer device, a ground station and a remote control device. The activate gimbal helps maintain the camera lens orthogonal to the water surface and reduce the extent of images being distorted. The image transfer device can monitor the captured image instantly. The operator controls the UAV by remote control device through ground station and can achieve the flying data such as flying height and GPS coordinate of UAV. The mobile system was then applied to field experiments. The deviation of velocities measured by UAV-LSPIV of field experiments and handhold Acoustic Doppler Velocimeter (ADV) is under 8%. The results of the field experiments suggests that the application of UAV-LSPIV can be effectively applied to surface flow studies.

  10. Prospek bisnis franchise di Indonesia

    OpenAIRE

    Suud, Muhammad

    2016-01-01

    Kentucky Fried Chicken (KFC), Mc. Donald, Pizza Hut, dan sebagainya, kini telah merambah di hampir semua kota besar. Kenyataan tersebut menunjukkan bahwa globalisasi tak terelakkan lagi. Bangsa-bangsa telah menjalin hubungan bisnis, melampaui batas-batas negara.

  11. La lunga attesa di Marsis

    Directory of Open Access Journals (Sweden)

    Fabrizio Bernardini

    2005-10-01

    Full Text Available Abbiamo parlato in altre occasioni di MARSIS e della sua progenie SHARAD, due esperimenti italiani per la misura di caratteristiche sottosuperficiali del pianeta Marte. Prodotti innovativi ed unici che nascondono un potenziale scientifico elevato. La strada per Marte però non è così facile come può sembrare e se la realizzazione degli strumenti non è stata esente da dolori, l’interpretazione e la divulgazione dei risultati non sono da meno. Le incertezze ed i dubbi sono però ora dissipati: l’esperimento MARSIS funziona perfettamente e per la prima volta nella storia dell’umanità abbiamo uno strumento e gli elementi per capire cosa c’è nel sottosuolo di un altro pianeta, senza aver inviato sul posto geologi ne’ tantomeno squadre per movimenti di terra.

  12. I ministri di culto delle confessioni religiose di minoranza: problematiche attuali

    Directory of Open Access Journals (Sweden)

    Matteo Carnì

    2015-06-01

    SOMMARIO: 1. I ministri di culto nell’ordinamento giuridico italiano - 2. I ministri di culto delle confessioni religiose dotate di intesa - 2.1. (segue L’individuazione dei ministri di culto - 2.2. (segue L’assistenza spirituale nelle strutture segreganti - 2.3.(segue Il matrimonio celebrato dai ministri di culto - 2.4 (segue Problematiche attinenti ai ministri di culto buddhisti – 3. I ministri di culto delle confessioni prive di intesa - 3.1. (segue In attesa della legge di approvazione: i ministri di culto della Congregazione cristiana dei Testimoni di Geova - 3.2. (segue Islam e ministri di culto - 4. Osservazioni conclusive.

  13. Pratiche di Social Networking: una prima sperimentazione nei corsi di italiano L2 per studenti Erasmus

    Directory of Open Access Journals (Sweden)

    Emanuela Cotroneo

    2012-04-01

    Full Text Available Tre Social Network realizzati con ilPratiche di social networking:  web service Ning in affiancamento alla didattica presenziale di alcuni corsi di lingua italiana per studenti Erasmus

  14. Tomographic particle image velocimetry of a water-jet for low volume harvesting of fat tissue for regenerative medicine

    Directory of Open Access Journals (Sweden)

    Drobek Christoph

    2015-09-01

    Full Text Available Particle Image Velocimetry (PIV measurements of a water-jet for water-assisted liposuction (WAL are carried out to investigate the distribution of velocity and therefore momentum and acting force on the human sub-cutaneous fat tissue. These results shall validate CFD simulations and force sensor measurements of the water-jet and support the development of a new WAL device that is able to harvest low volumes of fat tissue for regenerative medicine even gentler than regular WAL devices.

  15. Un improbabile precursore di Gutenberg?

    Directory of Open Access Journals (Sweden)

    Antonio Sartori

    2010-03-01

    Full Text Available The reconsideration of the small silver foil epigraph of the so called “Tesoro di Marengo” clarly demonstrates that the inscription has been made not “per mezzo di punzoni e stampi”, as proposed by the first publisher and never more discussed, but using a deep-drawing technique applied to the upper side, which the succeeding phases of deepening, rethink, corrections to many imperfections can be followed of.

  16. Profil Merokok pada Pelajar di Tiga SMP di Kota Padang

    Directory of Open Access Journals (Sweden)

    Yessy Susanti Sabti

    2015-09-01

    Full Text Available Abstrak   Merokok merupakan kontributor utama kematian.  Jumlah perokok semakin meningkat di seluruh dunia dan sebagian besar berada dinegara berkembang, termasuk Indonesia. Sebagai negara dengan perokok terbanyak ketiga di dunia, prevalensi perokok remaja di Indonesia semakin meningkat setiap tahun. Dengan menggunakan kuesionerGlobal Youth Tobacco Survey, kami meneliti profil merokok pada pelajar di tida SMP di kota Padang. Desain peneitian adalah crossectional. Data diperoleh dari kuesioner Global Youth Tobacco Survey, berbahasa Indonesia. Didapatkan sampel 240  murid dari 3 SMP dipilih secara acak di Kota Padang. Hasil : 27,7% murid pernah merokok, dan semuanya adalah laki-laki. 29%  mencoba rokok pada usia kurang dari 10 tahun. 37%  murid masih merokok sampai sekarang, 46% diantaranya sudah ketagihan rokok. Sebanyak 77,1% murid yang pernah merokok mempunyai orang tua perokok. Sebagian besar dari total sampel terpapar asap rokok lingkungan baik di rumah dan di tempat-tempat umum. Kesimpulan: Lebih dari seperempat pelajar di tiga SMP di kota Padang pernah merokok dan semuanya laki laki, dan mencoba merokok padausia kurang dari 10 tahun. Hampir seperlima sudah ketagihan merokok.Kata kunci: Pelajar, Merokok, Global Youth Tobacco SurveyAbstract Smoking is the mayor contibutor of death, and the number of smoker is growing overworld. More of them live in the developing country, including Indonesia. As the third of most smoker number, the teenager smoker prevalence in Indonesia is increase over year. By using Indonesian language adapted of Global Youth Tobacco Survey quessionaires, we researched smoking teenager behaviour and realted factors at Junior High School of Padang. Design of study is crossectional, datas collected from 240 students of three randomized selected Junior High School, by  Global Youth Tobacco Survey quessionaires that has adapted to Indonesian language. Results : 27,7% of students reported that they ever smoked cigarettes

  17. Modelling Ferroelectric Nanoparticles in Nematic Liquid Crystals (FERNANO)

    Science.gov (United States)

    2015-02-26

    DIPARTIMENTO DI CHIMICA FISICA ED INORGANICA VIALE DEL RISORGIMENTO 4 BOLOGNA, 40136 ITALY EOARD GRANT #FA8655-11-1-3046 Report...AND ADDRESS(ES) DIPARTIMENTO DI CHIMICA FISICA ED INORGANICA VIALE DEL RISORGIMENTO 4 BOLOGNA, 40136 ITALY 8. PERFORMING ORGANIZATION

  18. Pramana – Journal of Physics | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Author Affiliations. A Vitturi1 E G Lanza2 M V Andrés3 F Catara2 D Gambacurta2. Dipartimento di Fisica and INFN, Padova, Italy; Dipartimento di Fisica and INFN, Catania, Italy; Departamento de FAMN, Facultad de F ́ısica, Sevilla, Spain ...

  19. Interpolating Polynomial Macro-Elements with Tension Properties

    Science.gov (United States)

    2000-01-01

    Univ. Calgary, 1978. Paolo Costantini Dipartimento di Matematica " Roberto Magari" Via del Capitano 15 53100 Siena, Italy costantini~unisi. it Carla...Manni Dipartimento di Matematica Via Carlo Alberto 10 10123 Torino, Italy manniDdm .unito. it

  20. EGNOS: è ora di usarlo

    Directory of Open Access Journals (Sweden)

    Fabrizio Bernardini

    2006-04-01

    Full Text Available Dall’inizio di quest’anno EGNOS, European Geostationary Navigation Overlay Service, iniziativa dell’Unione Europea e dell’Agenzia Spaziale Europea, è operativo e nel corso dell’anno raggiungerà i livelli di servizio richiesti dapprima per le applicazioni commerciali e, all’inizio del 2007, quelli per le applicazioni Safety Of Life. Sarà dunque il conseguimento finale di EGNOS V2.1 al quale farà seguito un programma di evoluzione articolato in tre altre fasi che si estenderanno almeno fino alla fine del 2011 con ampliamenti della copertura, della fornitura di servizi anche nella nuovabanda L5, fino all’integrazione con Galileo. In questo articolo,che gode della collaborazione della Next SpA, realizzatriceanche dell’applicazione descritta nella rubrica Reports di questo stesso numero, vogliamo evidenziare alcuni aspetti del sistema che non ci sembra ancora ben apprezzato a livello utente e due prospettive note come SISNET ed ESA ALIVE.

  1. Fertilitas Remaja di Indonesia

    Directory of Open Access Journals (Sweden)

    Mugia Bayu Raharja

    2014-08-01

    Full Text Available Fertilitas remaja merupakan isu penting dari segi kesehatan dan sosial karena berhubungan dengan tingkat morbiditas serta mortalitas ibu dan anak. Tujuan penelitian adalah mempelajari faktor-faktor yang memengaruhi fertilitas remaja di Indonesia. Data yang digunakan adalah hasil Survei Demografi dan Kesehatan Indonesia tahun 2012 dengan unit analisis wanita usia subur yang termasuk dalam kategori usia remaja (15 - 19 tahun. Jumlah sampel sebanyak 6.927 responden. Analisis dilakukan dengan metode deskriptif dan inferensial menggunakan model regresi logistik biner. Hasil analisis menunjukkan bahwa satu dari sepuluh remaja wanita tersebut pernah melahirkan dan atau sedang hamil saat survei dilakukan; sebesar 95,2% dari remaja yang sudah pernah melahirkan, memiliki satu anak sisanya sebesar 4,8% memiliki dua atau tiga anak; sebesar 11,1% dari remaja wanita yang pernah kawin, pertama kali kawin pada usia 10 - 14 tahun. Secara statistik, terdapat hubungan yang signifikan antara kejadian fertilitas remaja dengan daerah tempat tinggal, pendidikan, status bekerja, serta tingkat kesejahteraan keluarga. Wanita berisiko tinggi mengalami fertilitas pada usia remaja adalah mereka yang tinggal di perdesaan, berpendidikan rendah, tidak bekerja dan berstatus ekonomi rendah. Rekomendasi berdasarkan hasil penelitian adalah akses ke tingkat pendidikan formal yang lebih tinggi bagi remaja wanita, penyediaan pelatihan usaha ekonomi kreatif terutama pada daerah perdesaan, peningkatan pengetahuan kesehatan reproduksi bagi remaja melalui pendidikan. Adolescent fertility is an important issue in terms of health and social care as it relates to the morbidity and mortality of mothers and children. This study aimed to know the factors that influence adolescent fertility in Indonesia. The data used was the result of Indonesian Demography and Health Survey in 2012 with units of analysis included women of childbearing age in the adolescent age group (15 - 19 years. Total

  2. DUALISME PENDIDIKAN DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Abdul Wahab

    2013-12-01

    Full Text Available Abstrak: Dalam konteks pendidikan istilah dualisme dan dikotomi memiliki makna yang sama yaitu pemisahan antara pendidikan umum dari pendidikan agama. Dikotomi selalu melahirkan pandangan pembedaaan di satu sisi dan penyamaaan di sisi yang lain. Pandangan dikotomis pada hakikatnya mengabaikan esensi atau nilai sprit pendidikan. Membedakan dan menyamakan lebih dimaknai pada ta-taran permukaan sehingga jelas merusak nilai spirit dari pendidikan Islam. Dua-lisme dan dikotomi bukan hanya pada tataran pemilahan, tetapi telah masuk pada wilayah pemisahan yang dalam operasionalnya memisahkan mata pelajaran umum dari mata pelajaran agama, sekolah umum dan madrasah yang penge-lolaannya berjalan terpisah-pisah. Puncaknya pada pemerintah Orde Baru yang mengeluarkan melalui Surat Keputusan Bersama (SKB pada tanggal 24 Maret 1975 yang menguatkan pemisahan itu hingga saat ini. Dampaknya terasa meru-gikan dan makna Islam menjadi sempit karena pengotak-kotakan ilmu akhirnya menomorduakan dan menganaktirikan pendidikan Islam. Sebagai solusi alter-natif harus diikuti upaya integrasi pengetahuan serta reposisi, yaitu cara pandang yang ilmu-ilmu Islam pada posisi yang sebenarnya. Abstract: In the educational context, the term dualism and dichotomy have the same mea-ning, namely the separation between general education and religious education. The terms also mean the separation between education system of Islamic and ge-neral educations. Moreover, talking about Islamic education is often addressed to Islamic institutions. Such perspectives are triggered by dichotomous view on education, differentiate in one side and equate on the other side. Consequently, the spirit value that is integrated into Islamic education is neglected. The terms, currently, have pervaded on the separation of general and Islamic subjects, public and madrasas Institutions, where the management has a policy respectively. The impacts are narrow minded in interpreting Islamic meaning

  3. Doppler Velocimetry of Current Driven Spin Helices in a Two-Dimensional Electron Gas

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Luyi [Univ. of California, Berkeley, CA (United States)

    2013-05-17

    Spins in semiconductors provide a pathway towards the development of spin-based electronics. The appeal of spin logic devices lies in the fact that the spin current is even under time reversal symmetry, yielding non-dissipative coupling to the electric field. To exploit the energy-saving potential of spin current it is essential to be able to control it. While recent demonstrations of electrical-gate control in spin-transistor configurations show great promise, operation at room temperature remains elusive. Further progress requires a deeper understanding of the propagation of spin polarization, particularly in the high mobility semiconductors used for devices. This dissertation presents the demonstration and application of a powerful new optical technique, Doppler spin velocimetry, for probing the motion of spin polarization at the level of 1 nm on a picosecond time scale. We discuss experiments in which this technique is used to measure the motion of spin helices in high mobility n-GaAs quantum wells as a function of temperature, in-plane electric field, and photoinduced spin polarization amplitude. We find that the spin helix velocity changes sign as a function of wave vector and is zero at the wave vector that yields the largest spin lifetime. This observation is quite striking, but can be explained by the random walk model that we have developed. We discover that coherent spin precession within a propagating spin density wave is lost at temperatures near 150 K. This finding is critical to understanding why room temperature operation of devices based on electrical gate control of spin current has so far remained elusive. We report that, at all temperatures, electron spin polarization co-propagates with the high-mobility electron sea, even when this requires an unusual form of separation of spin density from photoinjected electron density. Furthermore, although the spin packet co-propagates with the two-dimensional electron gas, spin diffusion is strongly

  4. Near-ground tornado-like vortex structure resolved by particle image velocimetry (PIV)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei [Iowa State University, Aerospace Engineering Department, Ames, IA (United States); University of Minnesota, Saint Anthony Falls Laboratory, Minneapolis, MN (United States); Sarkar, Partha P. [Iowa State University, Aerospace Engineering Department, Ames, IA (United States)

    2012-02-15

    The near-ground flow structure of tornadoes is of utmost interest because it determines how and to what extent civil structures could get damaged in tornado events. We simulated tornado-like vortex flow at the swirl ratios of S = 0.03-0.3 (vane angle {theta}{sub v} = 15 -60 ), using a laboratory tornado simulator and investigated the near-ground-vortex structure by particle imaging velocimetry. Complicated near-ground flow was measured in two orthogonal views: horizontal planes at various elevations (z = 11, 26 and 53 mm above the ground) and the meridian plane. We observed two distinct vortex structures: a single-celled vortex at the lowest swirl ratio (S = 0.03, {theta}{sub v} = 15 ) and multiple suction vortices rotating around the primary vortex (two-celled vortex) at higher swirl ratios (S = 0.1-0.3, {theta}{sub v} = 30 -60 ). We quantified the effects of vortex wandering on the mean flow and found that vortex wandering was important and should be taken into account in the low swirl ratio case. The tangential velocity, as the dominant velocity component, has the peak value about three times that of the maximum radial velocity regardless of the swirl ratio. The maximum velocity variance is about twice at the high swirl ratio ({theta}{sub v} = 45 ) that at the low swirl ratio ({theta}{sub v} = 15 ), which is contributed significantly by the multiple small-scale secondary vortices. Here, the results show that not only the intensified mean flow but greatly enhanced turbulence occurs near the surface in the tornado-like vortex flow. The intensified mean flow and enhanced turbulence at the ground level, correlated with the ground-vortex interaction, may cause dramatic damage of the civil structures in tornadoes. This work provides detailed characterization of the tornado-like vortex structure, which has not been fully revealed in previous field studies and laboratory simulations. It would be helpful in improving the understanding of the interaction between the

  5. An innovative experimental setup for Large Scale Particle Image Velocimetry measurements in riverine environments

    Science.gov (United States)

    Tauro, Flavia; Olivieri, Giorgio; Porfiri, Maurizio; Grimaldi, Salvatore

    2014-05-01

    Large Scale Particle Image Velocimetry (LSPIV) is a powerful methodology to nonintrusively monitor surface flows. Its use has been beneficial to the development of rating curves in riverine environments and to map geomorphic features in natural waterways. Typical LSPIV experimental setups rely on the use of mast-mounted cameras for the acquisition of natural stream reaches. Such cameras are installed on stream banks and are angled with respect to the water surface to capture large scale fields of view. Despite its promise and the simplicity of the setup, the practical implementation of LSPIV is affected by several challenges, including the acquisition of ground reference points for image calibration and time-consuming and highly user-assisted procedures to orthorectify images. In this work, we perform LSPIV studies on stream sections in the Aniene and Tiber basins, Italy. To alleviate the limitations of traditional LSPIV implementations, we propose an improved video acquisition setup comprising a telescopic, an inexpensive GoPro Hero 3 video camera, and a system of two lasers. The setup allows for maintaining the camera axis perpendicular to the water surface, thus mitigating uncertainties related to image orthorectification. Further, the mast encases a laser system for remote image calibration, thus allowing for nonintrusively calibrating videos without acquiring ground reference points. We conduct measurements on two different water bodies to outline the performance of the methodology in case of varying flow regimes, illumination conditions, and distribution of surface tracers. Specifically, the Aniene river is characterized by high surface flow velocity, the presence of abundant, homogeneously distributed ripples and water reflections, and a meagre number of buoyant tracers. On the other hand, the Tiber river presents lower surface flows, isolated reflections, and several floating objects. Videos are processed through image-based analyses to correct for lens

  6. High-resolution velocimetry in energetic tidal currents using a convergent-beam acoustic Doppler profiler

    Science.gov (United States)

    Sellar, Brian; Harding, Samuel; Richmond, Marshall

    2015-08-01

    An array of single-beam acoustic Doppler profilers has been developed for the high resolution measurement of three-dimensional tidal flow velocities and subsequently tested in an energetic tidal site. This configuration has been developed to increase spatial resolution of velocity measurements in comparison to conventional acoustic Doppler profilers (ADPs) which characteristically use divergent acoustic beams emanating from a single instrument. This is achieved using geometrically convergent acoustic beams creating a sample volume at the focal point of 0.03 m3. Away from the focal point, the array is also able to simultaneously reconstruct three-dimensional velocity components in a profile throughout the water column, and is referred to herein as a convergent-beam acoustic Doppler profiler (C-ADP). Mid-depth profiling is achieved through integration of the sensor platform with the operational commercial-scale Alstom 1 MW DeepGen-IV Tidal Turbine deployed at the European Marine Energy Center, Orkney Isles, UK. This proof-of-concept paper outlines the C-ADP system configuration and comparison to measurements provided by co-installed reference instrumentation. Comparison of C-ADP to standard divergent ADP (D-ADP) velocity measurements reveals a mean difference of 8 mm s-1, standard deviation of 18 mm s-1, and an order of magnitude reduction in realisable length scale. C-ADP focal point measurements compared to a proximal single-beam reference show peak cross-correlation coefficient of 0.96 over 4.0 s averaging period and a 47% reduction in Doppler noise. The dual functionality of the C-ADP as a profiling instrument with a high resolution focal point make this configuration a unique and valuable advancement in underwater velocimetry enabling improved quantification of flow turbulence. Since waves are simultaneously measured via profiled velocities, pressure measurements and surface detection, it is expected that derivatives of this system will be a powerful tool in

  7. Further development of microparticle image velocimetry analysis for characterisation of gas streams as a novel method of fuel cell development. Final report; Weiterentwicklung des Mikro-Particle Image Velocimetry Analyseverfahrens zur Charakterisierung von Gasstroemungen als neuartige Entwicklungsmethodik fuer Brennstoffzellen. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    The project aimed at a better understanding of the complex fluid-mechanical processes in the small ducts of bipolar plates. So far, an appropriate technology for in-situ measurement was lacking. The project therefore focused on the further development of microparticle image velocimetry in order to enable analyses of the local velocity distribution of a gas stream in a microduct. Further, measurements were carried out in the microducts of a fuel cell in the more difficult conditions of actual operation. (orig./AKB) [German] Anlass des Forschungsvorhabens war die komplizierten stroemungsmechanischen Zusammenhaenge in den kleinen Kanaelen der Bipolarplatten zu verstehen. Bisher stand keine Messtechnik zur Verfuegung, dies es erlaubt, die stroemungsmechanischen Prozesse in den Mikrokanaelen unter Realbedingungen in situ zu vermessen und mit der instantanen Zellleistung zu korrelieren, Ziel des Projektes war es daher, die Methode der Mikro-Partikel-Image-Velocimetry in der Art weiterzuentwickeln, dass eine Analyse der lokalen Geschwindigkeitsverteilung einer Gasstroemung in einem Mikrokanal ermoeglicht wird. Darueber hinaus wird als zweites Ziel des Projekts eine solche Messung unter den erschwerten Bedingungen einer betriebenen Brennstoffzelle in Mikrokanaelen einer Zelle durchgefuehrt.

  8. Rectification of Image Velocity Results (RIVeR): A simple and user-friendly toolbox for large scale water surface Particle Image Velocimetry (PIV) and Particle Tracking Velocimetry (PTV)

    Science.gov (United States)

    Patalano, Antoine; García, Carlos Marcelo; Rodríguez, Andrés

    2017-12-01

    LSPIV (Large Scale Particle Image Velocimetry) and LSPTV (Large Scale Particle Tracking Velocimetry) are used as relatively low-cost and non-intrusive techniques for water-surface velocity analysis and flow discharge measurements in rivers or large-scale hydraulic models. This paper describes a methodology based on state-of-the-art tools (for example, that apply classical PIV/PTV analysis) resulting in large-scale surface-flow characterization according to the first operational version of the RIVeR (Rectification of Image Velocity Results). RIVeR is developed in Matlab and is designed to be user-friendly. RIVeR processes large-scale water-surface characterization such as velocity fields or individual trajectories of floating tracers. This work describes the wide range of application of the techniques for comparing measured surface flows in hydraulic physical models to flow discharge estimates for a wide range of flow events in rivers (for example, low and high flows).

  9. Is obesity in women protective against osteoporosis?

    OpenAIRE

    Migliaccio, Silvia; Greco, Emanuela A; Fornari, Rachele; Donini, Lorenzo M; Lenzi, Andrea

    2011-01-01

    Silvia Migliaccio1,2, Emanuela A Greco1, Rachele Fornari1, Lorenzo M Donini1, Andrea Lenzi11Dipartimento di Medicina Sperimentale, Sezione di Fisiopatologia, Endocrinologia e Nutrizione, Università Sapienza di Roma, 2Dipartimento di Scienze della Salute, Università Foro Italico di Roma, ItaliaAbstract: The belief that obesity is protective against osteoporosis has recently come into question. The latest epidemiologic and clinical studies have shown that a high level of f...

  10. Esercizi di relatività generale

    CERN Document Server

    De Felice, Fernando

    2007-01-01

    La teoria della Relatività Generale ha la duplice funzione di descrivere la gravitazione come fenomeno fisico in sé e di fornire al contempo un algoritmo adeguato a descrivere tutte le altre leggi della fisica in presenza di gravitazione, sia essa reale o semplicemente indotta da uno stato di accelerazione. A tale scopo la teoria si presenta con una struttura matematica molto elaborata che richiede come requisito indispensabile conoscenze di geometria differenziale e di calcolo differenziale assoluto. La maggiore difficoltà nell'uso della teoria è riconoscere il legame fra la sua struttura formale e i fenomeni fisici che essa descrive, potendo in tal modo procedere alla loro verificabilità sperimentale. Gli esercizi sono essenziali al raggiungimento di tale obiettivo; lo scopo del libro pertanto è quello di fornire a studenti e cultori della materia una guida all'applicazione dei concetti teorici della Relatività Generale a una vasta gamma di situazioni fisiche.

  11. Pendidikan Karakter Di Sekolah

    Directory of Open Access Journals (Sweden)

    Edi Rohendi

    2016-08-01

    Full Text Available AbstrakPendidakan karakter tiba-tiba menjadi wacana hangat di dunia pendidikanIndonesiWa laupun gagasan ihwal karakter adalah gagasan tua setua sejarahpendidikan, namun kemunculan gagasan “pendidikan karakter “(characterbuildingmenginterupsi bangsa kita khususnya yang sedang melanda bangsaIndonesia. Masalah-masalah yang terjadi seperti kekerasan, korupsi, manipulasi,praktek-praktek kebohongan dalam dunia pendidikan mulai dari menyontekdalamujian sampai plagiat,kurang keteladanan dikalangan para pemimpin bangsa, dan sebagainya, sebenarnya menyangkut masalah karakter. Walaupun sudah terlambat dalam menerapkan pendidikan karakter disekolah, “But late than never”, masih banyak generasi kita para peserta didik yang duduk dibangku sekolah dan butuh pendidikan karakter agar dimasa depannya menjadi orang yang tidak hanya cerdas secara intelek tapi juga memiliki karakter. Dunia pendidikan diharapkan menjadi motor penggerak sebagaimana telah dikemukakan oleh Mendinas Muhammad Nuh dalam peringatan Hardiknas tahun2010 yang lalu bahwa “ Pembangunan dan Pendidikan Karakter menjadi keharusan karena pendidikan tidak hanya menjadikan peserta didik cerdas. Pendidikan juga untuk membangun budi pekerti dan sopan santun dalam kehidupan “. Batasan karakter berada dalam dua wilayah. Ia diyakini ada sebagai sifat fitri manusia, sementara pada sisi lain ia diyakini harus “dibentuk”melalui pendidikan , salah satunya melalui pendidikan karakterdisekolah. Pelaksanaan Pendidikan karakter disekolah sebagai alternativedikemukakan dalam makalah ini adalah: melalui Pembidanan dengan formula 4M (mengetaqhui, mencintai, menginginkan dan mengerjakan, juga dengan metode pembiasaan . Selain itu melalui metode : mengajarkan, keteladanan, mmenentukan prioritas dan praksis prioriotas. Kata Kunci : Pendidikian Karakter, pendidikan Akhlak dan pendidikan Moral.

  12. Stereo Imaging Velocimetry of Mixing Driven by Buoyancy Induced Flow Fields

    Science.gov (United States)

    Duval, W. M. B.; Jacqmin, D.; Bomani, B. M.; Alexander, I. J.; Kassemi, M.; Batur, C.; Tryggvason, B. V.; Lyubimov, D. V.; Lyubimova, T. P.

    2000-01-01

    Mixing of two fluids generated by steady and particularly g-jitter acceleration is fundamental towards the understanding of transport phenomena in a microgravity environment. We propose to carry out flight and ground-based experiments to quantify flow fields due to g-jitter type of accelerations using Stereo Imaging Velocimetry (SIV), and measure the concentration field using laser fluorescence. The understanding of the effects of g-jitter on transport phenomena is of great practical interest to the microgravity community and impacts the design of experiments for the Space Shuttle as well as the International Space Station. The aim of our proposed research is to provide quantitative data to the community on the effects of g-jitter on flow fields due to mixing induced by buoyancy forces. The fundamental phenomenon of mixing occurs in a broad range of materials processing encompassing the growth of opto-electronic materials and semiconductors, (by directional freezing and physical vapor transport), to solution and protein crystal growth. In materials processing of these systems, crystal homogeneity, which is affected by the solutal field distribution, is one of the major issues. The understanding of fluid mixing driven by buoyancy forces, besides its importance as a topic in fundamental science, can contribute towards the understanding of how solutal fields behave under various body forces. The body forces of interest are steady acceleration and g-jitter acceleration as in a Space Shuttle environment or the International Space Station. Since control of the body force is important, the flight experiment will be carried out on a tunable microgravity vibration isolation mount, which will permit us to precisely input the desired forcing function to simulate a range of body forces. To that end, we propose to design a flight experiment that can only be carried out under microgravity conditions to fully exploit the effects of various body forces on fluid mixing. Recent

  13. BUDIDAYA LOBSTER (Panulirus sp. DI VIETNAM DAN APLIKASINYA DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Akhmad Mustafa

    2013-12-01

    Full Text Available Desa Xuan Tun di Kecamatan Van Ninh Kota Nha Trang Provinsi Khanh Hoa merupakan lokasi pertama kegiatan budidaya lobster di Vietnam yang dilakuan pada tahun 1992. Secara umum di Kota Nha Trang, ada tiga jenis lobster yang dibudidayakan yaitu lobster mutiara (Panulirus ornatus, lobster pasir (Panulirus homarus, dan lobster batik (Panulirus longipes, karena benih lobster tersebut mudah didapat pada awalnya, cepat tumbuh, berukuran besar, warna cerah, dan memiliki harga yang tinggi. Kegiatan budidaya lobster pada dasarnya terdiri atas: penangkapan benih lobster, produksi tokolan lobster, dan pembesaran lobster yang masing-masing merupakan segmen usaha tersendiri. Pakan yang digunakan dalam produksi tokolan dan pembesaran lobster adalah berupa udang, kerang, tiram, cumi-cumi, dan ikan rucah, di mana sebagian besar dari pakan tersebut digunakan ikan rucah terutama pada pembesaran lobster. Sebagai akibat penggunaan pakan tersebut dan peningkatan jumlah keramba jaring apung yang cukup signifikan berdampak pada penurunan kualitas perairan yang memicu berkembangya penyakit susu (milky haemolymph disease sehingga terjadi penurunan produksi. Terkait dengan hasil yang didapatkan tersebut, ke depan diperlukan berbagai kegiatan termasuk untuk dapat diaplikasikan di Indonesia. Kegiatan tersebut meliputi: produksi benih lobster secara buatan di hatcheri dan penggunaan pakan buatan berupa moist pellet. Upaya pencegahan penyakit susu dan perlakuan-perlakuan praktis untuk mencegah perkembangan serangan penyakit susu juga perlu mendapat perhatian. Perkembangan budidaya lobster yang begitu cepat memicu terjadinya penurunan daya dukung lahan. Oleh karena itu, kegiatan untuk menentukan daya dukung lahan dan kesesuaian lahan menjadi penting untuk dilakukan untuk menentukan lokasi dan jumlah keramba jaring apung yang dapat dioperasikan. Penentuan daya dukung lahan dan evaluasi kesesuaian lahan tidak hanya dilakukan pada daerah yang

  14. Diasporici metropolitani: nuovi scenari quotidiani di lotta di classe

    Directory of Open Access Journals (Sweden)

    Sergio Straface

    2009-04-01

    Full Text Available Uno dei concetti su cui mi piace riflettere è quello della velocità. Più precisamente se sia possibile connettere l’intelligenza alla velocità. Oggi è necessario essere veloci e il vivere velocemente ha conquistato la quotidianità confondendosi strategicamente con la nozione di intelligenza. Le coordinate della surmodernità: l’accelerazione della storia, il restringimento dello spazio e l’individualizzazione dei destini pare abbiano imposto la velocità come conditio sine qua non sia improbabile conquistare un dignitoso ruolo sociale. Velocità come chiave di accesso, password obbligatoria, condizione connettiva con cui l’io finalmente accede all’attuale e soprattutto intelligente modo di vivere. La mia riflessione si concentrerà sull’esempio di lentezza proposto dai barboni, da ora in poi definiti diasporici metropolitani. Velocità vs lentezza, dunque, per una riflessione sulle contemporanee dinamiche del vivere metropolitano. Mi soffermerò su sensazioni, emozioni, ricordi e principalmente dubbi, per articolare una prima critica dell’equazione normativa “velocità uguale intelligenza” nonché per mostrare un esempio di resistenza, un modello altro in opposizione da quello dominate.

  15. CHE COSA RESTA DI CHERUBINI OGGI? DUE CASI DI STUDIO

    Directory of Open Access Journals (Sweden)

    Emanuele Miola

    2016-09-01

    Full Text Available A partire dagli anni Duemila, il fenomeno delle cosiddette risorgenze dialettali si è manifestato, nel panorama linguistico italiano, anche attraverso l’emergenza dei dialetti negli ambiti propri della Comunicazione Mediata dal Computer e, specialmente, sui siti internet creati ‘dal basso’, come l’enciclopedia libera e multilingue online Wikipedia. In questo articolo, si esaminerà il lascito di Cherubini e del suo Vocabolario milanese-italiano sull’edizione regionale lombarda della Wikipedia: gli articoli di quest’ultima saranno passati in rassegna, sia dal punto di vista ortografico, comparando le scelte del lessicografo milanese con quelle più in voga online, sia dal punto di vista morfo-sintattico, discutendo in questo secondo caso la presenza e la produttività di alcuni verbi sintagmatici. What remains of Cherubini today? Two case studies Since the beginning of the twenty-first century, the phenomenon of dialect resurgence has manifested in Italy through the emergence of dialects in Computer Mediated Communication, especially, on bottom-up created Web sites, like the free, multilingual, online encyclopedia Wikipedia. In this article, we will examine the legacy of Cherubini and his Milanese-Italian dictionary on the regional Lombard version of Wikipedia. We will review the articles both in terms of spelling, comparing the choices of Milanese lexicographer with those most utilized currently online, and from a morpho-syntactic point of view, discussing the presence and the productivity of some phrasal verbs.

  16. Volumetric 3-component velocimetry measurements of the flow field on the rear window of a generic car model

    Directory of Open Access Journals (Sweden)

    Tounsi Nabil

    2012-01-01

    Full Text Available Volumetric 3-component Velocimetry measurements are carried out in the flow field around the rear window of a generic car model, the so-called Ahmed body. This particular flow field is known to be highly unsteady, three dimensional and characterized by strong vortices. The volumetric velocity measurements from the present experiments provide the most comprehensive data for this flow field to date. The present study focuses on the wake flow modifications which result from using a simple flow control device, such as the one recently employed by Fourrié et al. [1]. The mean data clearly show the structure of this complex flow and confirm the drag reduction mechanism suggested by Fourrié et al. The results show that strengthening the separated flow leads to weakening the longitudinal vortices and vice versa. The present paper shows that the Volumetric 3-component Velocimetry technique is a powerful tool used for a better understanding of a threedimensional unsteady complex flow such that developing around a bluffbody.

  17. Particle image velocimetry measurement of complex flow structures in the diffuser and spherical casing of a reactor coolant pump

    Directory of Open Access Journals (Sweden)

    Yongchao Zhang

    2018-04-01

    Full Text Available Understanding of turbulent flow in the reactor coolant pump (RCP is a premise of the optimal design of the RCP. Flow structures in the RCP, in view of the specially devised spherical casing, are more complicated than those associated with conventional pumps. Hitherto, knowledge of the flow characteristics of the RCP has been far from sufficient. Research into the nonintrusive measurement of the internal flow of the RCP has rarely been reported. In the present study, flow measurement using particle image velocimetry is implemented to reveal flow features of the RCP model. Velocity and vorticity distributions in the diffuser and spherical casing are obtained. The results illuminate the complexity of the flows in the RCP. Near the lower end of the discharge nozzle, three-dimensional swirling flows and flow separation are evident. In the diffuser, the imparity of the velocity profile with respect to different axial cross sections is verified, and the velocity increases gradually from the shroud to the hub. In the casing, velocity distribution is nonuniform over the circumferential direction. Vortices shed consistently from the diffuser blade trailing edge. The experimental results lend sound support for the optimal design of the RCP and provide validation of relevant numerical algorithms. Keywords: Diffuser, Flow Structures, Particle Image Velocimetry, Reactor Coolant Pump, Spherical Casing, Velocity Distribution

  18. Aeroacoustic analysis of an airfoil with Gurney flap based on time-resolved particle image velocimetry measurements

    Science.gov (United States)

    Zhang, Xueqing; Sciacchitano, Andrea; Pröbsting, Stefan

    2018-05-01

    Particle image velocimetry for the experimental assessment of trailing edge noise sources has become focus of research in recent years. The present study investigates the feasibility of the noise prediction for high-lift devices based on time-resolved particle image velocimetry (PIV). The model under investigation is a NACA 0015 airfoil with a Gurney flap with a height of 6% of the chord length. The velocity fields around and downstream of the Gurney flap were measured by PIV and used to compute the corresponding pressure fields by solving the Poisson equation for incompressible flows. The reconstructed pressure fluctuations on the airfoil surface constitute the source term for Curle's aeroacoustic analogy, which was employed in both the distributed and compact formulation to estimate the noise emission from PIV. The results of the two formulations are compared with the simultaneous far-field microphone measurements in the temporal and spectral domains. Both formulations of Curle's analogy yield acoustic sound pressure levels in good agreement with the simultaneous microphone measurements for the tonal component. The estimated far-field sound power spectra (SPL) from the PIV measurements reproduce the peak at the vortex shedding frequency, which also agrees well with the acoustic measurements.

  19. Hybrid micro-/nano-particle image velocimetry for 3D3C multi-scale velocity field measurement in microfluidics

    International Nuclear Information System (INIS)

    Min, Young Uk; Kim, Kyung Chun

    2011-01-01

    The conventional two-dimensional (2D) micro-particle image velocimetry (micro-PIV) technique has inherent bias error due to the depth of focus along the optical axis to measure the velocity field near the wall of a microfluidics device. However, the far-field measurement of velocity vectors yields good accuracy for micro-scale flows. Nano-PIV using the evanescent wave of total internal reflection fluorescence microscopy can measure near-field velocity vectors within a distance of around 200 nm from the solid surface. A micro-/nano-hybrid PIV system is proposed to measure both near- and far-field velocity vectors simultaneously in microfluidics. A near-field particle image can be obtained by total internal reflection fluorescence microscopy using nanoparticles, and the far-field velocity vectors are measured by three-hole defocusing micro-particle tracking velocimetry (micro-PTV) using micro-particles. In order to identify near- and far-field particle images, lasers of different wavelengths are adopted and tested in a straight microchannel for acquiring the three-dimensional three-component velocity field. We found that the new technique gives superior accuracy for the velocity profile near the wall compared to that of conventional nano-PIV. This method has been successfully applied to precisely measure wall shear stress in 2D microscale Poiseulle flows

  20. Experimental Assessment of Flow Fields Associated with Heart Valve Prostheses Using Particle Image Velocimetry (PIV): Recommendations for Best Practices.

    Science.gov (United States)

    Raghav, Vrishank; Sastry, Sudeep; Saikrishnan, Neelakantan

    2018-03-12

    Experimental flow field characterization is a critical component of the assessment of the hemolytic and thrombogenic potential of heart valve substitutes, thus it is important to identify best practices for these experimental techniques. This paper presents a brief review of commonly used flow assessment techniques such as Particle image velocimetry (PIV), Laser doppler velocimetry, and Phase contrast magnetic resonance imaging and a comparison of these methodologies. In particular, recommendations for setting up planar PIV experiments such as recommended imaging instrumentation, acquisition and data processing are discussed in the context of heart valve flows. Multiple metrics such as residence time, local velocity and shear stress that have been identified in the literature as being relevant to hemolysis and thrombosis in heart valves are discussed. Additionally, a framework for uncertainty analysis and data reporting for PIV studies of heart valves is presented in this paper. It is anticipated that this paper will provide useful information for heart valve device manufacturers and researchers to assess heart valve flow fields for the potential for hemolysis and thrombosis.

  1. Optimization of in-line phase contrast particle image velocimetry using a laboratory x-ray source

    International Nuclear Information System (INIS)

    Ng, I.; Fouras, A.; Paganin, D. M.

    2012-01-01

    Phase contrast particle image velocimetry (PIV) using a laboratory x-ray microfocus source is investigated using a numerical model. Phase contrast images of 75 μm air bubbles, embedded within water exhibiting steady-state vortical flow, are generated under the paraxial approximation using a tungsten x-ray spectrum at 30 kVp. Propagation-based x-ray phase-contrast speckle images at a range of source-object and object-detector distances are generated, and used as input into a simulated PIV measurement. The effects of source-size-induced penumbral blurring, together with the finite dynamic range of the detector, are accounted for in the simulation. The PIV measurement procedure involves using the cross-correlation between temporally sequential speckle images to estimate the transverse displacement field for the fluid. The global error in the PIV reconstruction, for the set of simulations that was performed, suggests that geometric magnification is the key parameter for designing a laboratory-based x-ray phase-contrast PIV system. For the modeled system, x-ray phase-contrast PIV data measurement can be optimized to obtain low error ( 15 μm) of the detector, high geometric magnification (>2.5) is desired, while for large source size system (FWHM > 30 μm), low magnification (<1.5) would be suggested instead. The methods developed in this paper can be applied to optimizing phase-contrast velocimetry using a variety of laboratory x-ray sources.

  2. Iodine Tagging Velocimetry and Mechanism in the Hypersonic Near Wake of a MultiPurpose Crew Vehicle

    Science.gov (United States)

    Balla, R. Jeffrey

    2013-01-01

    This study demonstrates a new molecular tagging velocimetry (MTV) method for velocity measurements of high speed flow. It demonstrates offbody Iodine Tagging Velocimetry (ITV) in the hypersonic near wake of a MultiPurpose Crew Vehicle (MPCV) model. Experiments are performed in the NASA-Langley 31-inch Mach 10 air wind tunnel. A 0.5% I2 / N2 mixture is seeded on the leeward backshell of the model using a pressure tap. I2 laser-induced fluorescence is excited along a 5.5 mm line using an ArF excimer laser near 193 nm. Results indicate I2 absorbs at least 2 photons to produce iodine ions and electrons. These recombine as the tagged region is displaced downstream to produce I (2P3/2) whose emission is monitored at 206 nm. Results at P0 = 2.41 MPa (350 psi), T0 = 990K, and 10 micro-sec transit times produce velocities from 630-820 m/sec across the I2 seeded jet at a distance of 38.2 mm (25.5 jet diameters) downstream from the jet orifice. Maximum wake jet velocities near the shear layer are 59% of freestream velocity.

  3. Studio del comportamento di Acanthamoeba. polyphaga in presenza di Legionella pneumophila e di altri batteri ad habitat acquatico

    Directory of Open Access Journals (Sweden)

    M. Bondi

    2003-05-01

    Full Text Available Le amebe a vita libera sono state oggetto di diversi studi negli ultimi anni, non solo per le loro potenzialità patogene nei confronti dell’uomo, ma anche per l’importante ruolo che svolgono in natura, dove agiscono come predatori in grado di controllare le popolazioni batteriche. Alcuni degli organismi fagocitati però possono evitare la lisi fagosomiale e mantenere la loro condizione vitale a livello intracellulare, divenendo endosimbionti. Le amebe fungono così da riserva per questi batteri, proteggendoli da difficili condizioni extracellulari e provvedendo ad un ambiente consono alla loro replicazione. Tale tipo di interazione è particolarmente studiata in Legionella pneumophila, dal momento che l’ampia diffusione di questo germe, nonché la sua virulenza, pare siano fortemente influenzate dalla capacità di parassitare protozoi appartenenti ai generi Acanthamoeba, Naegleria e Balamuthia. Al fine di ottenere maggiori informazioni sui fattori favorenti o inibenti lo sviluppo di questi protozoi, è stato studiato il comportamento di un ceppo di Acanthamoeba polyphaga coltivato, in solido e in liquido, in associazione con L. pneumophila ed altri batteri ad habitat acquatico (Pseudomonas, Aeromonas, Achromobacter, Burkholderia. Su tappeti di cellule batteriche allestiti in Non Nutrient Agar (NNA, A.polyphaga si è mostrata in grado di moltiplicarsi utilizzando come nutrimento tutti i ceppi testati, nonostante alcuni, come Burkholderia cepacia SSV6 e Achromobacter xylox SS28, risultino più idonei al suo sviluppo. In piastre a pozzetti addizionate di acqua condottata autoclavata, il protozoo ha mostrato una buona capacità di sopravvivenza, non risultando inoltre influenzato dalla presenza di legionella o dei batteri acquatici testati. Dal momento che, fra i batteri descritti come capaci di vita intra-amebica, sono inclusi patogeni quali Chlamydia, Legionella, Listeria e Rickettsiae, risulta necessario riconsiderare la rilevanza clinica

  4. Proposal of development of an advanced IORT system; Proposta di sviluppo di un sistema IORT di avanguardia

    Energy Technology Data Exchange (ETDEWEB)

    Ronsivalle, C. [ENEA, Centro Ricerche Frascati, Rome (Italy). Unita tecnico scientifica Tecnologie Fisiche Avanzate; Casali, F. [Bologna Univ., Bologna (Italy), Dipartimento di fisica; Colavita, E. [Calabria Univ., Arcavacata (Italy). Diparimento di fisica; Lamanna, E. [Magna Graecia Univ., Germaneto (Italy). Dipartimento di medicina sperimentale e clinica

    2005-07-15

    In the last years there has been an increasing interest on IORT (Intraoperative Radiation Therapy), also because of the development of dedicated accelerators. This technique represents a very effective oncological treatment consisting in delivering a single high dose on a tumour bed soon after surgery resection. In the following we present the proposal of development of a last generation IORT system based on the use of a linear accelerator with variable energy in the range 3-15 MeV, operating in C band (5712 MHz). Respect to the accelerator used in the commercial IORT systems operating at a typical frequency of 2998 MHz (S band) limited to a maximum energy of 12 MeV, the use of a higher RF frequency allows an increase of the maximum energy. This extends the use of the IORT technique to a wider field of tumors and an improvement of the system in terms of compactness and weight reduction. In addition the machine will be provided with a devoted absolute dosimetry system that will strongly simplify the procedures of dosimetric characterization. We intend to develop the system by a collaboration between ENEA, some Universities (Bologna, Catanzaro and Cosenza) and the national industry. [Italian] Negli ultimi anni si e sviluppato un sempre maggior interesse intorno alla Radioterapia IntraOperatoria (IORT), una particolare tecnica radioterapica che permette di irradiare la zona interessata da un tumore durante un intervento chirurgico utilizzando un fascio di elettroni prodotto da un acceleratore. La diffusione di questa metodica e stata favorita dalla presenza sul mercato di acceleratori installabili direttamente in sala operatoria. Come conseguenza di questa disponibilita sono emerse sia nuove esigenze legate alle particolari applicazioni cliniche, sia richieste di facilita di utilizzo e perfomances sempre piu sofisticate. Viene qui presentata una proposta di sviluppo di un sistema IORT di ultima generazione basato sull'utilizzo di un acceleratore lineare con

  5. Proposal of development of an advanced IORT system; Proposta di sviluppo di un sistema IORT di avanguardia

    Energy Technology Data Exchange (ETDEWEB)

    Ronsivalle, C [ENEA, Centro Ricerche Frascati, Rome (Italy). Unita tecnico scientifica Tecnologie Fisiche Avanzate; Casali, F [Bologna Univ., Bologna (Italy), Dipartimento di fisica; Colavita, E [Calabria Univ., Arcavacata (Italy). Diparimento di fisica; Lamanna, E [Magna Graecia Univ., Germaneto (Italy). Dipartimento di medicina sperimentale e clinica

    2005-07-15

    In the last years there has been an increasing interest on IORT (Intraoperative Radiation Therapy), also because of the development of dedicated accelerators. This technique represents a very effective oncological treatment consisting in delivering a single high dose on a tumour bed soon after surgery resection. In the following we present the proposal of development of a last generation IORT system based on the use of a linear accelerator with variable energy in the range 3-15 MeV, operating in C band (5712 MHz). Respect to the accelerator used in the commercial IORT systems operating at a typical frequency of 2998 MHz (S band) limited to a maximum energy of 12 MeV, the use of a higher RF frequency allows an increase of the maximum energy. This extends the use of the IORT technique to a wider field of tumors and an improvement of the system in terms of compactness and weight reduction. In addition the machine will be provided with a devoted absolute dosimetry system that will strongly simplify the procedures of dosimetric characterization. We intend to develop the system by a collaboration between ENEA, some Universities (Bologna, Catanzaro and Cosenza) and the national industry. [Italian] Negli ultimi anni si e sviluppato un sempre maggior interesse intorno alla Radioterapia IntraOperatoria (IORT), una particolare tecnica radioterapica che permette di irradiare la zona interessata da un tumore durante un intervento chirurgico utilizzando un fascio di elettroni prodotto da un acceleratore. La diffusione di questa metodica e stata favorita dalla presenza sul mercato di acceleratori installabili direttamente in sala operatoria. Come conseguenza di questa disponibilita sono emerse sia nuove esigenze legate alle particolari applicazioni cliniche, sia richieste di facilita di utilizzo e perfomances sempre piu sofisticate. Viene qui presentata una proposta di sviluppo di un sistema IORT di ultima generazione basato sull'utilizzo di un acceleratore lineare con energia

  6. Trasforiiazioni Termoelastiche Finite di Solidi Incomprimibili

    Science.gov (United States)

    Signorini, A.

    Queste lezlioni hanno come direttiva una sintesi di quanto si trova sistematicamente sviluppato in una mia Memoria sulle trasformazioni termoelastiche finite di solidi incomprimibili, in corso di stampa negli Annali di Matematica pura e applicata t. XXXIX ( 1955) pp. 147-201 , Verranno anche esposti, come necessaria premessa, alcuni d ei risultati di due precedenti Memorie degli stessi Annali. Invece, per motivo di brevità, non potrò dare neppure un cenno delle ulteriori ricerche svilup pate dal prof. T. Manacorda in tre recentissimi suoi lavori:

  7. Questa è la storia di due ragazzi

    Directory of Open Access Journals (Sweden)

    Maria Lombardo

    2015-07-01

    Full Text Available Questa è la storia di due ragazzi per i quali le speranze di riuscita in una professione artistica come quella dell’attore - già difficile per chiunque - in percentuale erano una su dieci. Forse zero. E invece ce l’hanno fatta: uno a Parigi, l’altro a Roma. Entrambi di colore, entrambi di umili origini, arrivati in Europa come tanti, centinaia di migliaia, nel loro caso non da clandestini. Le storie di Bakary e Federico mostrano come il talento e la fortuna possano vincere le avversità, l’emarginazione, i pregiudizi.

  8. Studio di prevalenza delle polmoniti in un'Azienda opsedaliera di Bologna

    Directory of Open Access Journals (Sweden)

    E. Leoni

    2003-05-01

    Full Text Available

    Obiettivi: nell’ambito di un progetto di sorveglianza attiva dei casi di polmonite da legionella, è stata studiata la prevalenza di tutti i casi di polmonite ricoverati in un ospedale di Bologna, allo scopo di definirne la distribuzione per origine (comunitaria o nosocomiale, eziologia, caratteristiche individuali e di confrontarle con le polmoniti da legionella.

    Metodi: per ogni caso con diagnosi clinica e/o radiologica di polmonite è stato compilato un questionario, raccogliendo le informazioni dalle cartelle cliniche. Tutti i casi di polmonite non specificata sono stati inoltre sottoposti al test per la ricerca dell’antigene di legionella nelle urine.

  9. Studio di prototipo di calorimetro per neutroni per l'esperimento ALICE

    CERN Document Server

    Arnaldi, R; Cicalò, C; Cortese, P; De Falco, A; Dellacasa, G; De Marco, N; Gallio, M; Macciotta, P; Masoni, A; Musso, A; Oppedisano, C; Piccotti, A; Puddu, G; Scomparin, E; Siddi, S; Serci, E; Soave, C; Usai, G L; Vercellin, Ermanno

    1999-01-01

    ALICE e uno dei quattro esperimenti previsti ad LHC, al CERN, il cui scopo e lo studio delle osservabili che danno informazioni rilevanti sulla formazione del quark gluon plasma, che potrebbe essere prodotto in collisioni centrali Pb-Pb, di energia nel centro di massa di 5.5 A TeV.Il parametro di impatto di tali collisioni verra determinato grazie ad un insieme di calorimetri per protoni e neutroni che misureranno l'energia portata in avanti dai nucleoni non interagenti(spettatori).E' stato costruito un prototipo di calometro per neutroni, formato da piani di fibre di quarzo, posti a 45 gradi rispetto all'asse del fascio e inframmezzati da piani di materiale passivo denso(tungsteno). La luce Cerenkov prodotta nelle fibre dallo sciame sviluppato nel materiale passivo,viene raccolta da guide ottiche in aria.Verranno presentati i rilustati di un test previsto al CERN SPS per il luglio 1999.

  10. PhD Dissertations Tesi di dottorato

    Directory of Open Access Journals (Sweden)

    Redazione Reti Medievali (a cura di

    2003-12-01

    Full Text Available Report of PhD Dissertations.Guido Antonioli Conservator pacis et iustitie. La signoria di Taddeo Pepoli a Bologna (1337-1347, Tesi di dottorato di ricerca in Filologia romanza e cultura medievale (XIII ciclo, Università degli Studi di Bologna, 2001   Elisabetta Filippini «In vassallatico episcopi permanere debent». Rapporti vassallatici e concessioni beneficiali dei vescovi di Cremona fra X e XIII secolo, Tesi di dottorato di Ricerca in Storia Medievale (XV ciclo, Università Cattolica del Sacro Cuore di Milano, 2003   Marco Meschini, Innocenzo III e il "negotium pacis et fidei" in Linguadoca tra il 1198 e il 1215, Tesi di dottorato di ricerca in Storia medievale, Università Cattolica del Sacro Cuore, 2003   Fabrizio Ricciardelli The Politics of Exclusion in Florence (1215-1434, thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in History, University of Warwick, Department of History, April 2003 Renata Salvarani Baptizare pueros et decimas dare. Cura delle anime, strutturazione ecclesiastica e organizzazione delle campagne in area gardesana fra VIII e XIII secolo (diocesi di Brescia, Verona, Mantova e Trento, Tesi di dottorato in Storia medievale (XV ciclo, Università Cattolica del Sacro Cuore di Milano, 2002-2003   Vito Sibilio Le parole della prima crociata, Tesi di dottorato di ricerca in Storia dei centri delle vie e della cultura dei pellegrinaggi nel medioevo euromediterraneo, Università degli studi di Lecce, 2003Segnalazione di tesi di dottorato. Guido Antonioli Conservator pacis et iustitie. La signoria di Taddeo Pepoli a Bologna (1337-1347, Tesi di dottorato di ricerca in Filologia romanza e cultura medievale (XIII ciclo, Università degli Studi di Bologna, 2001   Elisabetta Filippini «In vassallatico episcopi permanere debent». Rapporti vassallatici e concessioni beneficiali dei vescovi di Cremona fra X e XIII secolo, Tesi di dottorato di Ricerca in Storia Medievale (XV

  11. Problemi di traduzione della Politica di AristoteleIl caso della traduzione in francese di Nicole Oresme

    Directory of Open Access Journals (Sweden)

    Claudio Fiocchi

    2008-07-01

    Full Text Available Necessità pratiche e riflessioni teoriche accompagnano il lavoro di Oresme, nella consapevolezza che la traduzione delle grandi opere è uno strumento fondamentale per la grandezza di un popolo.

  12. SULL’ALIMENTAZIONE DI DIECI SPECIE DI PASSERIFORMES IN ITALIA

    Institute of Scientific and Technical Information of China (English)

    RICCARDO GROPPALI

    1992-01-01

    <正> Dalla determinazione dei contenuti stomacali è stata studiata I’alimentazione insettivoradi dieci differenti specie di Passeriformi di provenienza italiana: Prispolone, Scricciolo, Pettirosso, Paglia-rolo, Capinera, Lui piccolo, Codibugnolo, Cinciallegra, Rigogolo ed Averla cenerina. On the feeding of ten species of Passeriformes in Italy. The feeding of ten different speciesof Passeriformes from Italy was studied thanks to identification of Insects and other Arthropoda foundin their stomach contents. The species examined are: Anthus trivialis, Troglodytes troglodytes, Erithacusrubecula, Acrocephalus paludicola, Sylvia atricapilla, Phylloscopus collybita, Aegithalos caudatus, Parusmajor, Oriolus oriolus and Lanius minor.

  13. Efficient optical probes for fast surface velocimetry: multiple frequency issues for Fabry and VISAR methods

    Science.gov (United States)

    Goosman, David R.; Avara, George R.; Perry, Stephen J.

    2001-04-01

    We have in the past used several types of optical probe lenses for delivering and collecting laser light to an experiment for laser velocimetry. When the test surface was in focus, however, the collected light would fill mostly the laser fiber rather than the collection fiber(s). We have designed, developed and used for 8 years nested-lens probe assemblies that solve this problem. Our first version used a commercial AR-coated glass achromat, which we cored to remove the inner fourth of its area. The core was then reinserted with its optical center offset from that of annulus by an amount slightly less than the separation between the laser and collector fibers. The laser and collector fibers are placed in contact with each other behind the lens and have NA values of 0.11 and 0.22, respectively. Because most of the collected light now focused on the collection fiber, this system was far superior to the single lens systems, but was laborious. For the last five years we used injection-molded acrylic aspheric nested lenses, which are inexpensive in quantity and require little labor to install into a probe. Only an azimuthal rotation and positioning of the fiber plane are needed to incorporate the plastic lens into a probe. Special ray-trace codes were written and used to design the lens, and many iterations by the molder were required to develop the injection processing parameters to produce a good lens, since it was thick for its diameter. These probes have real light collection efficiencies of 75% of theoretical, work well over a wide range of distances, with collection depths of field matching theory. The lenses can take 100 watts of pulsed power many times without damage, since the lens is designed so that reflections from the lens surface do not focus within the lens. The collection fiber size is designed to work with our manybeam velocimeter facility reported in a previous Congress, where the collection NA times collection fiber size exceeds the acceptance of the

  14. Attività antimicrobica, antivirale ed immunomodulante di peptidi anticorpali

    OpenAIRE

    Ciociola, Tecla

    2011-01-01

    Il progetto complessivo si è proposto di studiare le potenzialità immunoterapeutiche ed immunomodulanti di peptidi sintetici di derivazione anticorpale. I peptidi correlati ai CDR e molti decapeptidi, rappresentanti la regione variabile di un Ab anti-idiotipico ricombinante immagine interna di una tossina killer di lievito, hanno esibito attività fungicida in vitro nei confronti di Candida albicans. Un derivato alaninico di un decapeptide candidacida ha mostrato una incrementata efficacia ter...

  15. Fisica del nucleo stelle di neutroni

    CERN Document Server

    Bernardini, Carlo

    1982-01-01

    Studio sistematico delle masse nucleari ; energia di legame ; raggi nucleari dai nuclei speculari ; il nucleo in approssimazione di Thomas-Fermi ; introduzione allo scattering : caratterizzazione cinematica degli urti ; la sezione d'urto ; il fattore di forma dei nuclei ; gli atomi u-mesici ; proprieta elettromagnetiche statiche dei nuclei (momenti di multipolo) ; momento di quadrupolo elettrico dei nuclei ; momento d dipolo magnetico dei nuclei ; metodo delle risonanze magnetiche nucleari (NMR) ; misura del fattore giromagnetico e del momento di quadrupolo ; modelli nucleari a particelle indipendenti, il modello a shell ; l'interazione spin-orbita ; il modello a shell e le linee di Schmidt per il momento magnetico dei nuclei con "A" dispari ; nuclei non sferici (deformati) ; stelle di neutroni.

  16. LI PIRANDELLISMO DI BUZZATI (Prima Parte)

    African Journals Online (AJOL)

    User

    generazione, di ogni tipo d'ispirazione, inclusi i cosiddetti scrittori cattolici quale ... fantasticheria: lettura de “Il borghese stregato” di Buzzati, “Lingua e letteratura”, V, 8, ... padre. Profondamente lirica diventa la rievocazione della madre, specie.

  17. Indagine su un primo cittadino al di sopra di ogni sospetto. Renato Accorinti performer

    Directory of Open Access Journals (Sweden)

    Katia Trifiro'

    2014-05-01

    Lo studio, condotto all’insegna dei Performance Studies di impostazione schechneriana, si propone di interpretare, attraverso l’analisi dei comportamenti di Accorinti performer, alcuni dispositivi tipici delle forze antagoniste nel momento in cui, in tempi recenti, hanno assunto o assumono posizioni di potere.

  18. Coming to terms with our colonial past: Regina di fiori e di perle by ...

    African Journals Online (AJOL)

    Il romanzo Regina di fiori e di perle (2007) di Gabriella Ghermandi presenta due filoni narrativi: quello nel quale vengono raccolti oralmente i racconti dei testimoni degli anni coloniali sotto il fascismo, e quello del bildungsroman, nel quale il personaggio principale, Mahlet, cresce e si rende conto del proprio destino di ...

  19. Valutazione della sostenibilità ambientale tramite metodologia LCA di sistemi per lo sfruttamento di fonti alternative di energia e materiali

    OpenAIRE

    Chiavetta, Cristian

    2013-01-01

    La dissertazione ha riguardato l’analisi di sostenibilità di un sistema agronomico per la produzione di olio vegetale a fini energetici in terreni resi marginali dall’infestazione di nematodi. Il processo indagato ha previsto il sovescio di una coltura con proprietà biofumiganti (brassicacea) coltivata in precessione alla specie oleosa (soia e tabacco) al fine di contrastare il proliferare dell’infestazione nel terreno. Tale sistema agronomico è stato confrontato attraverso una analisi di cic...

  20. Principi generali di gestione della manutenzione

    CERN Document Server

    Furlanetto, Luciano; Macchi, Marco

    2006-01-01

    In questo volume vengono fornite le premesse per il superamento della tradizionale visione della manutenzione, quale inevitabile accidente e costo da ridurre, a favore di un'immagine culturale innovativa in cui la manutenzione consente un superamento del modello consumistico delle sostituzioni verso una ecosostenibilità del patrimonio di impianti e infrastrutture. Sulla base di queste premesse, ci si rivolge a manager, imprese, studiosi e studenti del campo dei servizi di manuntenzione.

  1. 2003: Censimento dei sistemi di Istituto

    OpenAIRE

    Carlesi, Carlo

    2003-01-01

    La procedura di 'Censimento' si propone di raccogliere informazioni relative a tutte le 'macchine' o 'sistemi' (Personal Computer, Workstation e Server) disponibili in Istituto per una migliore ed efficace utilizzazione delle risorse ai fini della sicurezza informatica. La procedura e' rivolta agli utenti che a qualunque titolo utilizzano e/o sono responsabili di una o piu' macchine. La procedura prevede la compilazione guidata (via browse) di due moduli: il primo modulo riguarda essenzialmen...

  2. Uno strumento per la creazione di valore nella realizzazione di edifici sostenibili: la certificazione LEED

    Directory of Open Access Journals (Sweden)

    S. Rick Fedrizzi

    2014-06-01

    Full Text Available Il presente lavoro ha l’obiettivo di delineare gli aspetti chiave della sostenibilità in ambito edilizio focalizzando l’attenzione sul sistema di certificazione LEED® quale strumento “universale” di supporto per la realizzazione, gestione e valutazione di edifici sostenibili. Nella prima parte del lavoro si descrive la rapida diffusione della certificazione LEED nel recente passato quale diretta conseguenza della capacità di questo strumento di rating di adattarsi sia alle specifiche tipologie di edifici, sia alle diversità climatiche e morfologiche dei siti. Nella seconda parte si procede invece a presentare ed analizzare gli aspetti economico-finanziari degli edifici sostenibili con riferimento sia alle metodologie valutative applicabili, sia ai dati della letteratura. Partendo dalle esperienze internazionali in tema di sostenibilità, si procede successivamente a descrivere la situazione italiana, evidenziando la percezione del mercato e le opportunità di sviluppo future.

  3. IL PIRANDELLISMO DI BUZZATI (Seconda Parte) - AJOL

    African Journals Online (AJOL)

    User

    del “Corriere”, ma al quale vuole confessare una strana storia iniziata all'epoca del suo apprendistato giornalistico. Il flashback, costellato da ..... pirandelliani anche della realtà primitiva della Sicilia, la storia che narra è una storia emblematica di un individuo maledetto, di un essere soggiogato dalle mani di un destino ...

  4. "Operations & innovation management. Alcuni casi di successo"

    OpenAIRE

    F. Gallmann; V. Veronesi; S. Zamboni

    2007-01-01

    La Unit Produzione e Tecnologia della SDA Bocconi svolge dal 1998 il progetto International Best Factory Award. Il successo dell’iniziativa ha indotto a estendere il campo di indagine al processo di innovazione: nel 2006 sono state lanciate due nuove iniziative di benchmarking, il Best Innovation Award e il Best Service Award.

  5. Lezioni di fisica teorica meccanica quantistica

    CERN Document Server

    Verde, Mario

    Ottica geometrica ed ottica ondulatoria ; risoluzion spettrale di Fourier ; meccanica classica e meccanica ondulatoria ; esempi di alcuni moti semplici in meccanica ondulatoria ; operatori lineari e loro rappresentazioni ; formulazione più generale della nuova meccanica ; costanti del movimento ; l'atomo di Idrogeno ; teoria delle perturbazioni.

  6. Le narrazioni come metodo di indagine sociologica

    Directory of Open Access Journals (Sweden)

    Rita Bichi

    2012-04-01

    Full Text Available L'incontro trentino ha dimostrato l'interesse crescente dei giovani sociologi per lo sviluppo dei metodi narrativi e la capacità che questi hanno di essere efficaci nell'analisi di svariati temi, dai racconti di malattia alle narrazioni identitarie, dallo studio di lavoro e organizzazioni a quello delle migrazioni, di genere e memoria. Tuttavia, l'interesse della sociologia italiana va visto in un quadro di sviluppo più ampio a livello europeo e americano dove, a partire dagli anni '90, l'intervento di alcuni autori come Lyotard, Bruner e Macintyre, ha sancito quella che alcuni autori hanno definito svolta narrativa. La sociologia, infatti, tende sempre più a valorizzare la narrazione come processo di conoscenza peculiare che è attivato costantemente nella vita quotidiana; la "rivoluzione" risiede nel fatto che la narrazione diventa oggetto della sociologia e la disciplina stessa valorizza il suo uso sia come strumento di indagine scientifica, sia come modo di conoscere che come modo di comunicare, rivendicando la legittimità scientifica all'ascolto della parola diretta degli individui coinvolti all'interno delle ricerche di stampo sociologico.

  7. La gestione dei flussi turistici tramite sistemi di trasporto innovativi: l’esempio di Perugia

    Directory of Open Access Journals (Sweden)

    Leonardo Naldini

    2010-10-01

    Full Text Available La città di Perugia ha, fin dagli anni ’70, unito alla sua capacità di attrazione turistica, dovuta al patrimonio storico ambientale plurimillenario, una volontà di affrontare il tema della mobilità urbana in maniera profondamente innovativa ed ambientalmente sostenibile. Il concetto della creazione di parcheggi di attestazione, serviti da percorsi meccanizzati di risalita verso l’acropoli, è stato recentemente ampliato dalla creazione del Minimetro, mezzo di trasporto innovativo, dal ridottissimo impatto ambientale, che unisce in soli 12 minuti, con un servizio semicontinuo, l’area di valle di Pian di Massiano, dotata di un capace parcheggio da circa 2800 posti auto, al centro cittadino, servendo diversi quartieri urbani. Tale sistema di trasporto, corridoio forte del trasporto pubblico urbano, ha fornito lo spunto per attuare una nuova modalità di gestione dei flussi turistici, che individua nel Minimetro la modalità principale di accesso al centro storico sia per i gruppi a numero ridotto, sia per i gruppi organizzati in arrivo con i bus turistici. L’organizzazione della mobilità turistica che ne è derivata costituisce un ulteriore passo in avanti lungo quell’itinerario di gestione della città che cerca di coniugare l’attrattiva turistica, con le sue ricadute in termini di crescita economica, e la salvaguardia del patrimonio storico artistico e della qualità della vita dei cittadini. Gli scenari futuri vedono un’iniezione di tecnologia in questo contesto, con l’introduzione nella gestione dei flussi turistici dei concetti di accreditamento, dell’infomobilità come supporto alle politiche urbane, del controllo unito alla fornitura di servizi georeferenziati.

  8. La logistica nei processi di trasformazione dell’area orientale di Napoli

    Directory of Open Access Journals (Sweden)

    Adriana Galderisi

    2010-07-01

    Full Text Available Stoccaggio e trasporto merci hanno assunto, già da alcuni anni, un ruolo rilevante nell’area orientale di Napoli, con impatti significativi sulla qualità urbana ed ambientale dell’area. In quest’area, anche grazie alla sua vicinanza ai principali nodi della mobilità (porto, aeroporto, stazione ferroviaria e alla significativa presenza di aree produttive dismesse o in dismissione, trovano oggi spazio numerose attività di stoccaggio e spedizione merci, in molti casi localizzate all’interno di ex aree industriali, in assenza di una reale ottica “sistemica”. Pertanto, a partire da una breve disamina dell’evoluzione dell’area orientale e di quanto previsto dagli strumenti urbanistici vigenti per la sua trasformazione, il contributo focalizza l’attenzione sul ruolo attuale dslle attività di stoccaggio e trasporto merci nell’area. Quindi, sulla base di alcune recenti esperienze di italiane e in riferimento ad ipotesi già avanzate per l’organizzazione di una piattaforma logistica nell’area orientale di Napoli -quale strumento per ottimizzare le necessità di stoccaggio e trasporto merci riducendone le esternalità negative- valuta la compatibilità di tali scelte con le prospettive di evoluzione/trasformazione dell’area e il potenziale ruolo che l’area potrebbe svolgere in una prospettiva di ri-organizzazione del trasporto merci in ambito urbano.

  9. Selective Two-Photon Absorptive Resonance Femtosecond-Laser Electronic-Excitation Tagging (STARFLEET) Velocimetry in Flow and Combustion Diagnostics

    Science.gov (United States)

    Jiang, Naibo; Halls, Benjamin R.; Stauffer, Hans U.; Roy, Sukesh; Danehy, Paul M.; Gord, James R.

    2016-01-01

    Selective Two-Photon Absorptive Resonance Femtosecond-Laser Electronic-Excitation Tagging (STARFLEET), a non-seeded ultrafast-laser-based velocimetry technique, is demonstrated in reactive and non-reactive flows. STARFLEET is pumped via a two-photon resonance in N2 using 202.25-nm 100-fs light. STARFLEET greatly reduces the per-pulse energy required (30 µJ/pulse) to generate the signature FLEET emission compared to the conventional FLEET technique (1.1 mJ/pulse). This reduction in laser energy results in less energy deposited in the flow, which allows for reduced flow perturbations (reactive and non-reactive), increased thermometric accuracy, and less severe damage to materials. Velocity measurements conducted in a free jet of N2 and in a premixed flame show good agreement with theoretical velocities and further demonstrate the significantly less-intrusive nature of STARFLEET.

  10. Phase identification of quasi-periodic flow measured by particle image velocimetry with a low sampling rate

    International Nuclear Information System (INIS)

    Pan, Chong; Wang, Hongping; Wang, Jinjun

    2013-01-01

    This work mainly deals with the proper orthogonal decomposition (POD) time coefficient method used for extracting phase information from quasi-periodic flow. The mathematical equivalence between this method and the traditional cross-correlation method is firstly proved. A two-dimensional circular cylinder wake flow measured by time-resolved particle image velocimetry within a range of Reynolds numbers is then used to evaluate the reliability of this method. The effect of both the sampling rate and Reynolds number on the identification accuracy is finally discussed. It is found that the POD time coefficient method provides a convenient alternative for phase identification, whose feasibility in low-sampling-rate measurement has additional advantages for experimentalists. (paper)

  11. Investigation on convective mixing of triple-jet. Evaluation of turbulent quantities using particle image velocimetry and direct numerical simulation

    International Nuclear Information System (INIS)

    Kimura, Nobuyuki; Igarashi, Minoru; Kamide, Hideki

    2002-01-01

    We performed a water experiment on parallel triple-jet and a calculation using a direct numerical simulation (DNS) for a quantification of thermal striping. The local temperatures and velocities were measured by using thermocouples and the particle image velocimetry (PIV), respectively. The calculation was carried out using the quasi-DNS code, DINUS-3, which was based on the finite difference method. The oscillation of the jets obtained from the flow visualization was related to the movements of the twin vortices between the jets by using the PIV. The experimental temperatures/velocities results were close to the numerical results. The heat transportation among the jets was evaluated by using the turbulent heat fluxes obtained from the quasi-DNS. (author)

  12. Laser Doppler velocimetry based on the optoacoustic effect in a RF-excited CO{sub 2} laser

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Teaghee; Choi, Jong Woon [Department of Information and Communication, Honam University, Seobong-dong 59-1, Gwansan-gu, Gwangju 506-714 (Korea, Republic of); Kim, Yong Pyung [College of Electronics and Information, Kyunghee University, 1 Seocheon-dong, Giheung-gu, Yongin-si, Gyeonggi-do 446-701 (Korea, Republic of)

    2012-09-15

    We present a compact optoacoustic laser Doppler velocimetry method that utilizes the self-mixing effect in a RF-excited CO{sub 2} laser. A portion of a Doppler-shifted laser beam, produced by irradiating a single wavelength laser beam on a moving object, is mixed with an originally existing laser beam inside a laser cavity. The fine change of pressure in the laser cavity modulated by the Doppler-shifted frequency is detected by a condenser microphone in the laser tube. In our studies, the frequency of the Doppler signal due to the optoacoustic effect was detected as high as 50 kHz. Our measurements also confirmed that the signal varied linearly with the velocity of the external scatterer (the moving object) and the cosine of the angle between the laser beam and the velocity vector of the object.

  13. Identification of patients at risk for preeclampsia with the use of uterine artery Doppler velocimetry and copeptin.

    Science.gov (United States)

    Yeşil, Ali; Kanawati, Ammar; Helvacıoğlu, Çağlar; Kaya, Cihan; Özgün, Çağseli Göksu; Cengiz, Hüseyin

    2017-11-01

    To investigate the relationship between maternal copeptin levels and uterine artery Doppler examination and progress of preeclampsia. A cross-sectional study was designed with women those were screened at 20 + 0 - 24+  6 weeks' gestation between May 2014 and August 2014. The obstetric records of all normotensive women were examined. Uterine artery Doppler velocimetry results and serum copeptin levels were measured. The patients were divided into two groups according to normal (n = 67) and abnormal uterine artery Doppler (n = 21) findings. Maternal age was significantly lower in group 1 (n = 21, 23.9%) than in group 2 (n= 67, 76.1%) (p preeclampsia. There was also a significant correlation between copeptin levels and the presence of preeclampsia. (p = 0.002). Copeptin levels are significantly higher in patients who develop preeclampsia.

  14. Experimental investigation of the dynamics of a hybrid morphing wing: time resolved particle image velocimetry and force measures

    Science.gov (United States)

    Jodin, Gurvan; Scheller, Johannes; Rouchon, Jean-François; Braza, Marianna; Mit Collaboration; Imft Collaboration; Laplace Collaboration

    2016-11-01

    A quantitative characterization of the effects obtained by high frequency-low amplitude trailing edge actuation is performed. Particle image velocimetry, as well as pressure and aerodynamic force measurements, are carried out on an airfoil model. This hybrid morphing wing model is equipped with both trailing edge piezoelectric-actuators and camber control shape memory alloy actuators. It will be shown that this actuation allows for an effective manipulation of the wake turbulent structures. Frequency domain analysis and proper orthogonal decomposition show that proper actuating reduces the energy dissipation by favoring more coherent vortical structures. This modification in the airflow dynamics eventually allows for a tapering of the wake thickness compared to the baseline configuration. Hence, drag reductions relative to the non-actuated trailing edge configuration are observed. Massachusetts Institute of Technology.

  15. L2F and LDV velocimetry measurement and analysis of the 3-D flow field in a centrifugal compressor

    Science.gov (United States)

    Fagan, John R., Jr.; Fleeter, Sanford

    1989-01-01

    The flow field in the Purdue Research Centrifugal Compressor is studied using a laser two-focus (L2F) velocimeter. L2F data are obtained which quantify: (1) the compressor inlet flow field; (2) the steady-state velocity field in the impeller blade passages; and (3) the flow field in the radial diffuser. The L2F data are compared with both laser Doppler velocimetry (LDV) data and predictions from three-dimensional inviscid and viscous flow models. In addition, a model is developed to calculate the effect on the measurement volume geometry of refraction by curved windows. Finally, the advantages and disadvantages of using the L2F for turbomachinery measurements is discussed in terms of measurement accuracy, ease of use, including sample time per correlated event and the ability to make measurements in regions of high noise due to stray radiation from wall reflections.

  16. A synchronized particle image velocimetry and infrared thermography technique applied to convective mass transfer in champagne glasses

    Science.gov (United States)

    Beaumont, Fabien; Liger-Belair, Gérard; Bailly, Yannick; Polidori, Guillaume

    2016-05-01

    In champagne glasses, it was recently suggested that ascending bubble-driven flow patterns should be involved in the release of gaseous carbon dioxide (CO2) and volatile organic compounds. A key assumption was that the higher the velocity of the upward bubble-driven flow patterns in the liquid phase, the higher the volume fluxes of gaseous CO2 desorbing from the supersaturated liquid phase. In the present work, simultaneous monitoring of bubble-driven flow patterns within champagne glasses and gaseous CO2 escaping above the champagne surface was performed, through particle image velocimetry and infrared thermography techniques. Two quite emblematic types of champagne drinking vessels were investigated, namely a long-stemmed flute and a wide coupe. The synchronized use of both techniques proved that the cloud of gaseous CO2 escaping above champagne glasses strongly depends on the mixing flow patterns found in the liquid phase below.

  17. Eulerian-Lagrangian analysis for particle velocities and trajectories in a pure wave motion using particle image velocimetry.

    Science.gov (United States)

    Umeyama, Motohiko

    2012-04-13

    This paper investigates the velocity and the trajectory of water particles under surface waves, which propagate at a constant water depth, using particle image velocimetry (PIV). The vector fields and vertical distributions of velocities are presented at several phases in one wave cycle. The third-order Stokes wave theory was employed to express the physical quantities. The PIV technique's ability to measure both temporal and spatial variations of the velocity was proved after a series of attempts. This technique was applied to the prediction of particle trajectory in an Eulerian scheme. Furthermore, the measured particle path was compared with the positions found theoretically by integrating the Eulerian velocity to the higher order of a Taylor series expansion. The profile of average travelling distance is also presented with a solution of zero net mass flux in a closed wave flume.

  18. Rimozione Urbana: La Necessità di una Nuova Direzione di Attività di Pubblica Amministrazione

    Directory of Open Access Journals (Sweden)

    Eneida Criscuolo Gabriel Bueno Silva

    2015-12-01

    Full Text Available Questo lavoro si propone di discutere la legitimità delle decisioni amministrative nel democratico Stato di diritto; il discorso e la democrazia sono correlati nel mondo contemporaneo, mostrando la necessità di discussione pubblica in attività amministrativa, in tale contesto, con il passare dell'atto amministrativo, la razionalità degli decisioni amministrativa dovrebbe essere dimostrata attraverso del processo amministrativo come mezzo di discussione in una prospettiva democratica. Pacifico che il discorso è un mezzo attraverso il quale la democrazia può avvenire, ma devono osservare qui: senza partecipazione sociale, senza coscienza politica, il discorso porta a una democrazia apparente. Questo articolo discute la relazione tra democrazia, discorso e attività amministrativa in processi di rimozione urbana, indagando gli aspette che riguardano, a fini de equilibrio nel rapporto tra stato e cittadino. Questo lavoro ha origine de una ricerca de 2232 documenti, utilizzando la tecnica di analisi di contenuto.

  19. EGNOS: è ora di usarlo

    Directory of Open Access Journals (Sweden)

    Fabrizio Bernardini

    2006-04-01

    anche dell’applicazione descritta nella rubrica Reports di questo stesso numero, vogliamo evidenziare alcuni aspetti del sistema che non ci sembra ancora ben apprezzato a livello utente e due prospettive note come SISNET ed ESA ALIVE.

  20. Dinamika Perjuangan Muslim di Palestina

    OpenAIRE

    Rosyid, Moh

    2015-01-01

    Upaya negara Palestina untuk mewujudkan kedaulatannya sebagai negara mendapat tantangan oleh arogansi Israel yang ingin menganeksasinya dengan dalih 'ajaran' dan keyakinannya. Usaha optimal Israel mencaplok wilayah negara Israel dirancang dengan langkah yang rapi, yakni sejak munculnya protokol zionis hingga eksisnya negara Israel. Sejak itu, konflik yang diderita negara Palestina membuat negaranya makin miskin karena energinya tersedot untuk memperjuangkan kedaulatan, di tengah upaya yang ha...

  1. DINAMIKA MASYARAKAT LOKAL DI PERBATASAN

    Directory of Open Access Journals (Sweden)

    Zaenuddin Hudi Prasojo

    2012-12-01

    Masyarakat perbatasan yang ada di Indonesia cenderung masuk dalam kelompok masyarakat yang tertinggal dari berbagai aspek pembangunan. Kajian mengenai masyarakat lokal di wilayah-wilayah perbatasan di Indonesia belum terlalu meng­gembirakan baik dari segi jumlah maupun dari segi dampak hasil kajian yang berupa aksi kebijakan pasca kajian. Nanga Badau yang terletak di daerah per­batasan Kalimantan Barat (Indonesia dan Serawak (Malaysia merupakan salah satu wilayah perbatasan yang tertinggal. Tulisan ini memoret isu-isu dinamika dan eksistensi tradisi lokal dalam kerangka globalisasi. Tampak bahwa sikap ramah dan menghormati pendatang merupakan salah satu bentuk nyata bahwa mereka sangat terbuka dengan adanya arus global dan lokal. Mereka juga me­miliki kesadaran diri akan posisi mereka sebagai bagian dari penduduk dunia. Adanya ruang interaksi bagi dunia luar, seperti mudahnya akses keluar masuk ke negara lain mengakibatkan pola interaksi, informasi dan komunikasi etnis Iban menjadi berkembang. Hal tersebut dapat dilihat pada aktivitas masyarakat Iban sehari-hari yang telah memanfaatkan dan menggunakan perangkat handphone, televisi dan teknologi modern lainnya.

  2. nelle pagine di dolores prato

    African Journals Online (AJOL)

    User

    il libro possa vedere la luce. Passeranno altri diciassette anni prima dell'uscita dell'edizione integrale del testo, curata da Giorgio Zampa sul dattiloscritto originale. 3. Cfr. a riguardo Veschi (2008:82) che, nel sottolineare l'importanza dell'organizzazione. «spaziale» del libro, individua nella casa degli zii il primo di una serie ...

  3. Improved di-electric composition

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, R C

    1915-03-29

    An improved di-electric composition is disclosed composed of pitch or bitumen which is melted, and to which is added, while molten, a quantity of finely ground or pulverized spent shale, the whole being mixed or stirred to make a homogeneous composition, substantially as described.

  4. Simulating Dynamic Stall in a 2D VAWT: Modeling strategy, verification and validation with Particle Image Velocimetry data

    International Nuclear Information System (INIS)

    Ferreira, C J Simao; Bijl, H; Bussel, G van; Kuik, G van

    2007-01-01

    The implementation of wind energy conversion systems in the built environment renewed the interest and the research on Vertical Axis Wind Turbines (VAWT), which in this application present several advantages over Horizontal Axis Wind Turbines (HAWT). The VAWT has an inherent unsteady aerodynamic behavior due to the variation of angle of attack with the angle of rotation, perceived velocity and consequentially Reynolds number. The phenomenon of dynamic stall is then an intrinsic effect of the operation of a Vertical Axis Wind Turbine at low tip speed ratios, having a significant impact in both loads and power. The complexity of the unsteady aerodynamics of the VAWT makes it extremely attractive to be analyzed using Computational Fluid Dynamics (CFD) models, where an approximation of the continuity and momentum equations of the Navier-Stokes equations set is solved. The complexity of the problem and the need for new design approaches for VAWT for the built environment has driven the authors of this work to focus the research of CFD modeling of VAWT on: .comparing the results between commonly used turbulence models: URANS (Spalart-Allmaras and k-ε) and large eddy models (Large Eddy Simulation and Detached Eddy Simulation) .verifying the sensitivity of the model to its grid refinement (space and time), .evaluating the suitability of using Particle Image Velocimetry (PIV) experimental data for model validation. The 2D model created represents the middle section of a single bladed VAWT with infinite aspect ratio. The model simulates the experimental work of flow field measurement using Particle Image Velocimetry by Simao Ferreira et al for a single bladed VAWT. The results show the suitability of the PIV data for the validation of the model, the need for accurate simulation of the large eddies and the sensitivity of the model to grid refinement

  5. Droplet morphometry and velocimetry (DMV): a video processing software for time-resolved, label-free tracking of droplet parameters.

    Science.gov (United States)

    Basu, Amar S

    2013-05-21

    Emerging assays in droplet microfluidics require the measurement of parameters such as drop size, velocity, trajectory, shape deformation, fluorescence intensity, and others. While micro particle image velocimetry (μPIV) and related techniques are suitable for measuring flow using tracer particles, no tool exists for tracking droplets at the granularity of a single entity. This paper presents droplet morphometry and velocimetry (DMV), a digital video processing software for time-resolved droplet analysis. Droplets are identified through a series of image processing steps which operate on transparent, translucent, fluorescent, or opaque droplets. The steps include background image generation, background subtraction, edge detection, small object removal, morphological close and fill, and shape discrimination. A frame correlation step then links droplets spanning multiple frames via a nearest neighbor search with user-defined matching criteria. Each step can be individually tuned for maximum compatibility. For each droplet found, DMV provides a time-history of 20 different parameters, including trajectory, velocity, area, dimensions, shape deformation, orientation, nearest neighbour spacing, and pixel statistics. The data can be reported via scatter plots, histograms, and tables at the granularity of individual droplets or by statistics accrued over the population. We present several case studies from industry and academic labs, including the measurement of 1) size distributions and flow perturbations in a drop generator, 2) size distributions and mixing rates in drop splitting/merging devices, 3) efficiency of single cell encapsulation devices, 4) position tracking in electrowetting operations, 5) chemical concentrations in a serial drop dilutor, 6) drop sorting efficiency of a tensiophoresis device, 7) plug length and orientation of nonspherical plugs in a serpentine channel, and 8) high throughput tracking of >250 drops in a reinjection system. Performance metrics

  6. Teoria dell'elettromagnetismo fenomeni e leggi fondamentali : energia dei campi e delle distribuzioni di carica, applicazioni di meccanica analitica e statistica, teoria della relatività, emissione e propagazione di onde elettromagnetiche

    CERN Document Server

    Tenaglia, Livio

    1956-01-01

    Leggi fondamentali dell'elettromagnetismo ; le equazioni di Lagrange, di Hamilton e di Jacobi, il principio di Fermat ; applicazioni di meccanica analitica all'elettromagnetismo ; teoria statica dell'irraggiamento ; fondamenti di teoria della relatività ; propagazione delle onde elettromagnetiche proprietà elementari dei conduttori ; emissione di onde elettromagnetiche ; richiami analitici ; unità di misura per le grandezze del campo elettromagnetico.

  7. L’identificazione di virus citopatogeni isolati dall’ambiente:ricerca ed applicazione di protocolli analitici

    Directory of Open Access Journals (Sweden)

    A. Carducci

    2003-05-01

    Full Text Available

    Obiettivi: la ricerca dei virus enterici in matrici ambientali, soprattutto nei reflui urbani, risulta di grande interesse sia per la valutazione del rischio di natura virale sia per compiere studi epidemiologici.

    Lo scopo di questo lavoro è stato l’applicazione parallela di diverse tecniche attualmente in uso in virologia clinica a isolati citopatogeni ambientali al fine di ottenere una precisa identificazione degli agenti rilevati.

    Metodi: sono stati analizzati 21 campioni di aerosol, provenienti da impianti di depurazione di reflui civili a fanghi attivi, e risultati citopatogeni in colture di cellule BGM.

    Dopo una nuova semina in “shell vials”, su tre linee cellulari continue per mettere in evidenza eventuali differenze nello spettro di citopatogenicità. Per l’identificazione degli isolati virali, sono state adottate in parallelo: microscopia elettronica, tecniche biomolecolari di amplificazione genica, elettroforesi su gel di poliacrilamide (PAGE, test immunoenzimatici, sieroneutralizzazione.

    Risultati: la semina in “shell vials” ha confermato la
    presenza di particelle virali infettive in tutti i campioni
    tranne uno; inoltre ha permesso di ridurre il
    tempo di comparsa dell’effetto citopatico a 3-4 giorni
    contro i 6-8 giorni necessari seminando in fiasche.
    La microscopia elettronica ha individuato la presenza
    di particelle enterovirus-simili in 18 dei 21
    campioni e di virioni della famiglia Reoviridae in 8.
    La positività dei campioni è stata ottenuta, inoltre,
    con la RT-PCR, per 2 campioni di enterovirus e 2 di
    reovirus e con la PAGE in 6 campioni. Il presente
    studio ha portato ad un’identificazione sufficientemente
    certa di reovirus in 2 campioni e di enterovirus
    in 1 campione.

    Conclusioni: l’identificazione di isolati ambientali si

  8. La figura di Maria Maddalena nella tradizione agostiniana del XII secolo e l'allegoria nuziale in Bernardo di ClairvauxUn'ipotesi di interpretazione alla luce di categorie di ordine psicoanalitico

    Directory of Open Access Journals (Sweden)

    Elena Cartotto

    2008-07-01

    La lettura viene condotta sulla base di categorie concettuali di carattere psicoanalitico, in quanto tali categorie trovano la propria origine, prima ancora che nel pensiero, nella più concreta e profonda esperienza umana. Ed è proprio il collocarsi all'interno di questa viva esperienza umana che consente di cogliere in modo più diretto la dimensione antropologica che pare emergere dagli scrittori monastici di questo periodo.

  9. Life cycle assessment applied to two different municipal solid waste processes; Analisi del ciclo di vita di due diverse possibilita' di smaltimento di rifiuti solidi urbani

    Energy Technology Data Exchange (ETDEWEB)

    Corti, A. [Florence Univ., Florence (Italy). Dipt. di Energetica Sergio Stecco; Sirini, P. [Florence Univ., Florence (Italy). Dipt. di Ingegneria Civile

    2001-12-01

    The application of Life Cycle Assessment (LCA) methodology as environmental balance tool is particularly suitable for the study of complex system such as municipal solid waste (MSW) collection, treatment and disposal systems. In this case a detailed analysis is carried out referring to an overall environmental balance based on two different waste treatments: land filling and incineration. The comparison carried out based on the LCA methodology and referring to specific process assumptions allowed to foreground that waste to energy treatments get a net overall balance lower than all the different land filling options, referring also to energy recovery from collected biogas. [Italian] La applicazione di metodologie di bilancio ambientale LCA (Life Cycle Assessment) si adatta particolarmente allo studio disistemi complessi quali quelli di raccolta, trattamento e smaltimento di rifiuti. In questo caso viene affrontata nel dettaglio la valutazione in termini di bilancio complessivo di diverse opzioni di trattamento basate su posa a discarica e trattamento termico. Il confronto effettuato mediante il percorso metodologico seguito, ha permesso di valutare, sulla base delle ipotesi di processi fatte, come il trattamento termico con recupero energetico abbia un bilancio netto ambientale inferiore rispetto a qualsiasi opzione di posa a discarica, anche dotata di recupero energetico dal biogas.

  10. Allacciare i fili spezzati: analisi di tre autobiografie di persone divenute disabili

    Directory of Open Access Journals (Sweden)

    Rosalba Perrotta

    2011-04-01

    Full Text Available Leggere autobiografie consente di conoscere esperienze e momenti della vita che restano ignoti a chi non li ha vissuti. Le autobiografie ci svelano un mondo e, nello stesso tempo, ci introducono in esso. Illustrano e spiegano senza illustrare e senza spiegare. Catturano il lettore nella narrazione e, rendendolo protagonista di quello che accade, gli fanno provare le emozioni di chi racconta e gli mostrano la realtà attraverso i suoi occhi. La corrente sociologica dell’Interazionismo simbolico, un approccio che dà particolare rilievo ai significati attribuiti dagli uomini agli oggetti di cui hanno esperienza, considera le storie di vita uno strumento di indagine prezioso. Il racconto di un tratto della vita, o della vita in genere, consente di raggiungere una conoscenza della realtà soggettiva di chi narra molto superiore rispetto a quella ottenuta attraverso questionari o interviste strutturate.

  11. l'isola di demetra e il destino di kore nelle poesie di dacia maraini1

    African Journals Online (AJOL)

    User

    infine, con il racconto biografico, Bagheria, uscito nel 1993,5 ci fornisce forse la chiave adatta a spiegare con risvolti più profondi il vincolo che la lega all'isola materna. Il libro è un viaggio affascinante nella memoria in cui rievoca luoghi, tempi, personaggi, odori e colori di tempi passati. Emerge la. Bagheria mitica della sua ...

  12. Aspetti di continuità di lungo periodo dell’architettura di Venezia e osservazione sulla tipicità di alcuni processi di stratificazione

    Directory of Open Access Journals (Sweden)

    Trovò, Francesco

    2010-12-01

    Full Text Available In order to interpret the links between Venice and Byzantium, it is firstly described how earliest houses in Venice were decorated by using sculptures coming from trading places. It is described the use of disassembled elements and the replacement of others, such as cornices, windows’ elements, coats of arms, among others. These were used firstly as a revival (Neo-Byzantine, 15th century, and later as reflection of the Venetian society «prudence», related to its behaviours and traditions. This prudence is mainly shown in the Renaissance. Besides this, other aspects such as the type of building and the façades, which are the main transformed surface, are analysed with the aim of researching periodical and characteristic dynamics, mainly in those façades showing stylistic renewal and new elements. Some external façades have maintained specific and easy observable characteristics, so they can be associated to a determined stylistic and morphological period. Other façades are stratified, as it is shown by the presence of elements (windows, cornices, … of different building phases. After tracing the main stratifying processes in about 40 study-cases, thanks to a macroscopic analysis, some ways of new composition elements and different stratified units are described. According to this, it is clear that the main principle is the searching for symmetry. Finally, some ways of intervention on the façades are described, highlighting some significant cases.[it] Nella prima parte dell’articolo viene descritto il modo di adornare le prime case veneziane con sculture importate dai luoghi del commercio, come ricostruzione del legame fra Venezia e Bisanzio. Si descrive l’uso di disaggregare e riposizionare vari elementi, come cornici, elementi di finestre, stemmi, prima come un iniziale revival, sia esso neobizantino o riferito al XV secolo, poi come manifestazione di «prudenza» della società veneziana, legata ai costumi, alle tradizioni. La

  13. Analisa Kepuasan Konsumen Di Restaurant “X” Di Surabaya

    OpenAIRE

    Wibowo, Handoko Surya; Tunggal, Gabriel Jeffri Wea; Jokom, Regina

    2015-01-01

    Penelitian ini ditunjukan untuk menganalisa tingkat kesenjangan antara harapan dari konsumen terhadap Kenyataan yang diterima oleh konsumen dan mengukur tingkat kepuasan konsumen di Restoran “X” dengan menggunakan atribut DINESERV. Penelitian ini menggunakan Importance Performance Analysis(IPA). Hasil dari penelitian ini adalah kesenjangan antara harapan dan Kenyataan yang diukur menggunakan atribut DINESERV adalah Kenyataan yang diterima oleh konsumen sangat tidak sesuai dengan harapan konsu...

  14. Obbligo di sicurezza del prestatore di lavoro ed effettività della tutela antinfortunistica

    OpenAIRE

    Alessia Gabriele

    2012-01-01

    Il saggio affronta il tema della sicurezza e della salute dei lavoratori quale diritto fondamentale. Dopo l'analisi del panoram­a normativo internazionale e comunitario, l'A. si sofferma sulla posi­zione di garanzia assegnata al prestatore di lavoro subordinato nell'ordinamento interno, con particolare attenzione ai diritti di for­mazione e di informazione intimamente connessi al correlati­vo obbli­go di sicurezza del prestatore di lavoro. Le conclusioni cui giunge una parte della giurisprude...

  15. Caravaggio e il Maccheronico di Teofilo Folengo

    Directory of Open Access Journals (Sweden)

    Bernardo Piciché

    2013-06-01

    Full Text Available Il presente studio ipotizza un’affinità tra Caravaggio e Teofilo Folengo, argomentando che la pittura del primo presenta analogie estetiche e etiche con la produzione in latino maccheronico del secondo. Il Baldus costituisce un tipico esempio di quella che Genette definirà come «parodia seria»: attraverso il rovesciamento e la irrisione beffarda Folengo ingaggia tenzone contro l’arte paludata e il travisamento dei valori cristiani. Non si tratta qui di stabilire un’influenza di Folengo su Caravaggio, bensì un’analogia, in virtù di un filo di congiunzione ideale, la cui presumibilità viene corroborata anche dal substrato biografico-culturale e da comune spirito religioso. Sia in Folengo che in Caravaggio sono stati individuati i caratteri di un certo modo della cultura lombarda di essere “contro” al punto che il duo Folengo-Caravaggio sembra epitomizzare l’antitesi al decorum curialcortigianesimo di Castiglione e Raffaello. Il Cristo-paradosso costituisce la vera fonte ispiratrice per entrambi. La comparazione tra due arti deve tenere conto dei diversi strumenti espressivi, e questo costituirà uno dei soggetti di riflessione nel testo. Se l’ipotesi della consentaneità viene ragionevolmente difesa, perché non individuare una componente maccheronica anche nell’arte di Caravaggio? Agli storici d’arte, tuttavia, decidere se si possa considerare il maccheronico come categoria pittorica

  16. Ricerche sugli enterobatteri nelle feci di Chirotteri

    Directory of Open Access Journals (Sweden)

    Dino Scaravelli

    2003-10-01

    Full Text Available Dal 2002, grazie al protocollo stipulato tra il gruppo di studio chirotteri del Museo di Onferno e l?Istituto Zooprofilattico Sperimentale della Lombardia e dell?Emilia, sezione di Forlì, si è iniziato un progetto di studio sulla enteroflora di varie specie di Chirotteri. I campioni fecali o più raramente da carcassa, sono stati procssati mediante sistemi standardizzati e tipizzati mediante Enterotubes, creando anche una collezione di riferimento. Le ricerche ad oggi hanno interessato campioni provenienti da diverse regioni e da un certo pool di specie: Myotis daubentonii, M. blythii, M. myotis, Miniopterus schreibersii, Nyctalus noctula, Pipistrellus kuhlii, Rhinolophus ferrumequinum, R. hipposideros. Non sono stati mai identificati vettori di zoonosi o altri batteri che siano di alcun interesse per la salute umana, mentre si descrivono qui alcune specie nuove per la fauna italiana in relazione ai Chirotteri quali Providencia alcalifaciens in N.noctula, Serratia marcescens in M. schreibersii e Klebsiella oezaenale in R. hipposideros. Il lavoro invita inoltre ad una maggiore collaborazione e a stringere accordi per ampliare la possibile raccolta dei campioni.

  17. DAYA SAING BAWANG MERAH DI WILAYAH SENTRA PRODUKSI DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Haris Fatori Aldila

    2017-03-01

    Full Text Available The objectives of this study are to analyze (1 the profitability of shallot farming, (2 competitiveness of shallot farming through competitive and comparative advantages and (3 impact of government’s policy on competitiveness of shallot farming in three production centers in Indonesia (Cirebon, Brebes, and Tegal. Data analysis method used Policy Analysis Matrix (PAM. The results show that shallot farming in Cirebon, Brebes and Tegal is financially profitable but economically unprofitable. The analysis of the competitiveness of shallot farming in Cirebon, Brebes and Tegal shows that shallot farming has no comparative advantage but has competitive advantage. The impacts of government’s policy on output show that the government has given protection on the price of shallot. Meanwhile, the government's policy on input is disincentive to farmers. Shallot farmers have to pay inputs more expensive than they should be; however, simultaneously, the government's policy on input and output support the shallot production in Cirebon, Brebes and Tegal.Keywords: comparative advantage, competitive advantage, government’s policy, policy analysis matrix, shallotAbstrakTujuan dari penelitian ini adalah menganalisis keuntungan usaha tani bawang merah, menganalisis daya saing bawang merah melalui keunggulan kometitif dan komparatif, serta menganalisis dampak kebijakan pemerintah pada usaha tani bawang merah di tiga sentra produksi di Indonesia (Cirebon, Brebes, Tegal. Metode analisis data menggunakan PAM (Policy Analysis Matrix. Hasil penelitian menunjukkan bahwa usaha tani bawang merah di Cirebon, Brebes dan Tegal menguntungkan secara finansial tetapi tidak menguntungkan secara ekonomi. Hasil analisis daya saing usaha tani bawang merah di Cirebon, Brebes dan Tegal menunjukkan usaha tani bawang merah tidak memiliki keunggulan komparatif tetapi masih memiliki keunggulan kompetitif. Dampak kebijakan pemerintah terhadap output menunjukkan adanya proteksi

  18. Metodologie di rilievo tra ricerca e innovazione tecnologica per un caso di archeologia medievale: Torre Melissa in provincia di Crotone

    Directory of Open Access Journals (Sweden)

    Francesca Fatta

    2017-12-01

    Full Text Available   Il complesso di Torre Melissa è uno dei manufatti storici di pregio che si affacciano sulle coste calabresi del mare Jonio. Una torre-castello d’epoca aragonese sottoposta ad un restauro conservativo agli inizi degli anni duemila. In quella occasione, la torre fu rilevata con procedure manuali e l’ausilio di una stazione totale. Nel 2014 si è proceduto con un rilievo eseguito con strumenti digitali d’alta definizione (laser scanner, fotografia digitale e telecamera applicata a drone. La comparazione tra i due rilievi, effettuati con metodologie differenti, mostrano delle disuguaglianze semantiche evidenti che mettono in risalto i progressi delle odierne strumentazioni per la definizione di modelli 3D d’altissima precisione, fondamentali per le pratiche di tutela e valorizzazione di un patrimonio architettonico complesso e stratificato

  19. KNOWLEDGE MANAGEMENT DI INSTANSI PEMERINTAH

    Directory of Open Access Journals (Sweden)

    Tri Pujadi

    2016-01-01

    Full Text Available Tujuan yang ingin dicapai adalah menyusun model manajemen pengetahuan di instansi pemerintahan. Kegiatan ini menggunakan metode deskriptif dengan menggunakan metode soft system methodology. Faktor yang mendukung keberhasilan kegiatan ini adalah tersedianya data dan informasi diberbagai instansi pemerintah dan swasta. sekaligus penguasaan metodologi dalam analisis. Persaingan internasional pada saat ini cenderung lebih ketat dan kompleks, untuk itu perlu dicari cara agar mendapatkan produk atau jasa yang diperlukan oleh masyarakat. Inovasi yang kreatif dapat meningkatkan pelayanan terhadap masyarakat yang memerlukannya. Sehingga unit-unit di pemerintahan sangat tergantung dari pengelolaan pengetahuan apakah akan terjadi siklus knowledge yaitu perpindahan dari tacit ke explicit knowledge dan ke tacit knowledge. Oleh karena itu pengelolaan knowledge (knowledge management ini menjadi penting bagi pengembangan pelayanan, karena masyarakat semakin kritis dan cerdas dan meningkatkan kemampuan sumber daya manusia bagi pemangku kepentingan.

  20. Una nuova rubrica di Archeomatica

    Directory of Open Access Journals (Sweden)

    Renzo Carlucci

    2005-02-01

    Full Text Available La parte umanistica della nostra rivista è in espansione e da questo numero si parte con un'altra avventura che si accoda a quella già avviata l'anno scorso con Arte e Scienza. Archeologia, Informatica e Geomatica s'incontreranno su uno spazio loro dedicato, la rubrica di Archeomatica. Essa prende il via con un articolo sul Sistema Informativo Geografico della Valle del Colosseo, le cui varie cartografie, da quelle storiche fino alle più recenti, i disegni e i rilievi di scavo s'integrano in modelli numerici CAD, tridimensionali, riuniti da un'unica relazione spaziale che li colloca e li indicizza mettendoli a disposizione dell'utente.

  1. La ricostruzione grafica del pavimento musivo di una villa romana

    Directory of Open Access Journals (Sweden)

    Caterina Gattuso

    2015-01-01

    Full Text Available Nel processo di analisi conoscitiva finalizzato alla conservazione e/o al restauro di un manufatto storico, la documentazione grafica offre un contributo importante ai fini della redazione del quadro anamnesico. Essa costituisce uno strumento conoscitivo che, nel rappresentare e registrare lo stato di conservazione nonché gli eventuali interventi di restauro cui il bene è stato sottoposto, permette di completare e di integrare le informazioni già ottenute mediante il dossier fotografico. In questo contesto si vuole dimostrare l’importanza del disegno informatico, da intendere come strumento utile per l’elaborazione di un corretto piano diagnostico, illustrando la ricostruzione grafica di una complessa pavimentazione musiva che decora un particolare ambiente di una villa di epoca romana posta sulle rive del lago d’Esaro nel comune di Roggiano Gravina (CS, ottenuta attraverso l’uso di un particolare software di design grafico e disegno vettoriale.

  2. Book review, Igiene e Tecnologie degli Alimenti di Origine Animale Giampaolo Colavita (a cura di

    Directory of Open Access Journals (Sweden)

    Manuel Graziani

    2008-09-01

    Full Text Available Igiene e Tecnologie degli Alimenti di Origine Animale si avvale del contributo di 33 autori, tutti soci dell’Associazione Italiana Veterinari Igienisti (AIVI, che garantiscono l’appropriata trattazione di una materia estremamente vasta e dinamica. Il manuale nasce da un’iniziativa finalizzata alla realizzazione di un testo che rifletta e possa soddisfare le esigenze didattiche degli insegnamenti di un’ampia serie di materie universitarie: Igiene e Tecnologie degli Alimenti di Origine Animale della Facoltà di Medicina Veterinaria, di Agraria, nei corsi di Scienze e Tecnologie Alimentari, di Scienze e Tecnologie delle Produzioni Animali, nel corso di laurea in Tecniche della Prevenzione nell’ambiente e nei Luoghi di Lavoro, nonché in altri corsi di studio dove si insegnano le discipline relative all’igiene e alla sicurezza degli alimenti.Sono stati trattati gran parte degli alimenti di origine animale, i prodotti a base di carne, il latte e i prodotti derivati, i prodotti della pesca freschi e trasformati, i prodotti dell’alveare, le uova e gli ovoprodotti. Di particolare interesse appare il capitolo riguardante la diagnostica analitica degli alimenti, considerato che le moderne metodologie analitiche risultano fondamentali per affrontare le tematiche legate all’igiene e alla sicurezza alimentare.Il volume ha una finalità prevalentemente didattica ma è comunque rivolto a tutti coloro che operano nel campo dell’Igiene e delle Tecnologie Alimentari. Infatti, visti gli argomenti trattati come le tossinfezioni e le intossicazioni alimentari, la conservazione, il confezionamento e l’etichettatura dei prodotti alimentari, anche i professionisti del settore possono trarre dal testo elementi utili per la loro attività. Per esempio argomenti quali l’analisi del rischio, le attività di audit ed i sistemi di accreditamento e di certificazione sono particolarmente utili per chi opera nelle Aziende Sanitarie Locali e negli Istituti

  3. Biopotensial Elektroda di Bidang Medis

    OpenAIRE

    Zairul Arifin

    2009-01-01

    Dalam hal mengukur dan mencatat potensial dan arus listrik dalam tubuh, perlu ada penghubung antara tubuh dengan peralatan pengukur elektronik. Fungsi penghubung ini dilakukan oleh biopotensial elektroda. Biopotensial elektroda ada pada berbagai jenis sistem peralatan medis seperti yang dipergunakan untuk pengukuran ECG, EEG, EMG dan potensial intraseluler. Selama bertahun-tahun telah dikembangkan banyak jenis elektroda yang berbeda untuk mencatat berbagai potensial di dalam tubuh, misalny...

  4. Telematika Dakwah Di Dunia Broadcasting

    OpenAIRE

    Syarifuddin, Syarifuddin

    2012-01-01

    Peran teknologi informasi dan teledakwah dalam aktifitas dakwah menjadi tren baru pada era teknologi informasi untuk memvisualisasikan dakwah dalam bentuk media cetak dan elektronik. Teknologi informasi dan teledakwah merupakan sarana penunjang dakwah yang mutakhir jika kita ingin menyebarkan dakwah keseluruh pelosok desa di Indonesia, yang dapat dijangkau oleh infrastruktur media Televisi lain sebagainya. Seorang Da'i perlu memahami penggunaaan serta pemilihan media teknologi informasi dan t...

  5. METAMORFOSIS PESANTREN DI ERA GLOBALISASI

    Directory of Open Access Journals (Sweden)

    Muhammad Jamaluddin

    2012-07-01

    Full Text Available Abstrak: Tulisan ini mendeskripsikan perkembangan peran dan fungsi pesantren sejak awal "kelahirannya" yang terjadi pada kehidupan masyarakat tradisional sampai pada perubahan model pesantren yang menyesuaikan dengan kemajuan teknologi informasi. Model pendidikan pesantren menjamur jauh sebelum lembaga pendidikan formal didirikan di Indonesia, sehingga kontribusinya sangat besar dalam pembangunan bangsa ini. Mempertahankan eksistensinya di tengah tren perkembangan masyarakat modern tentunya tidak mudah. Karena pesantren, di satu sisi, merupakan lembaga penguatan keagamaan dan moral, tetapi di sisi lain ia harus mampu beradaptasi dan bermetamorfosis sesuai dengan perkembangan masyarakat modern. Tantangan besar dalam masyarakat modern adalah dekadensi moral dan agama, lambatnya laju perkembangan ekonomi masyarakat, dan tingginya angka konsumerisme masyarakat. Berdasarkan tantangan ini, pesantren dapat melakukan revitalisasi peran dan fungsinya sebagai lembaga pendidikan dan pusat pemberdayaan masyarakat.     Abstract: This paper describes the development of the role and function of pesantren starting from the beginning of "its birth"  in traditional society to model of pesantren the advancement of information technology. Pesantren has flourished long before the formal educational institutions established in Indonesia. Thus, it has great contribution to the development of this nation. Maintaining its existency  in the middle of the development trend of modern society is certainly not easy for pesantren. In one side, it is an institution for strengthening of religious and moral issues but on the other hand it must be able to adapt and metamorphose in accordance with the development of modern society. The major challenges in modern society is the moral and religious decadence, the slow pace of economic development, and the high rate of consumerism. For these challenges, pesantren can revitalize its role and function as educational institutions

  6. Reddito minimo e piena occupazione. Note sull'idea dei "piani di lavoro garantito" e di "occupazione di ultima istanza"

    OpenAIRE

    Foggi, Jacopo

    2016-01-01

    L'articolo costituisce una rapida disamina di una proposta politica per la piena occupazione e la lotta alla povertà, poco nota nel dibattito politico, filosofico ed economico italiano. L'interesse della proposta, sviluppata inizialmente da Hyman Minsky e ripresa indipendentemente da diversi economisti in particolare di indirizzo post-keynesiano, sta essenzialmente nell'affrontare congiuntamente lotta alla povertà e perseguimento della piena occupazione, all'interno di un quadro macroeconomic...

  7. KEBIJAKAN PENEMPATAN APOTEKER DI PUSKESMAS

    Directory of Open Access Journals (Sweden)

    Sudibyo Supardi

    2013-03-01

    pharmacist assignment: (a District Health Office was aware of the need of pharmacist, but in panning pharmacist was not regarded as a priority compared to other health workers, (b the request for pharmacist was not based on the real organization needs resulted from the analysis of work burden such as regulated, (c limited formation given by BKN, and such that the assignment of health workers was not based on their competencies, ang (d Training of health personnel has not been done because of budget limitations. Key words: pharmacist, community health center, assignment policy ABSTRAK Dalam Peraturan Pemerintah RI Nomor 51 tahun 2009 disebutkan pelayanan resep dokter di pelayanan kefarmasian (salah satunya puskesmas harus dilakukan oleh apoteker. Saat ini hanya 10% puskesmas yang memiliki apoteker. Belum diketahui bagaimana kebijakan penempatan apoteker di puskesmas dan permasalahan yang terkait penempatan apoteker di puskesmas. Tujuan penelitian adalah mendapatkan informasi tentang peran institusi daerah terkait dengan kebijakan penempatan apoteker di puskesmas dan hambatannya. Hasil penelitian diharapkan sebagai masukan bagi pihak yang terkait untuk meningkatkan jumlah dan peran apoteker di puskesmas. Penelitian potong lintang (cross sectional dengan pendekatan kualitatif dilakukan terhadap instansi daerah yang terkait dengan peran apoteker di puskesmas pada tahun 2011. Lokasi penelitian dipilih berdasarkan keberadaan perguruan tinggi farmasi yang terakreditasi A atau B di Pulau Jawa, dengan asumsi ketersediaan apoteker memadai untuk bekerja di puskesmas, yaitu Provinsi Banten, Jawa Barat, Daerah Istimewa Yogyakarta, Jawa Timur. Dari masing-masing provinsi diambil satu kota, yaitu Kota Tangerang, Kota Bandung, Kabupaten Bantul dan Kota Surabaya. Informan untuk wawancara mendalam adalah pejabat dari Dinkes Provinsi, Dinkes Kabupaten/Kota, Badan Kepegawaian daerah, dan Kepala Puskesmas. Sedangkan informan diskusi kelompok terarah adalah para apoteker yang mewakili Dinkes

  8. la metamorfosi del personaggio nei romanzi neostorici di roberto pazzi

    African Journals Online (AJOL)

    User

    imbalsamando co' loro inchiostri le Imprese de Prencipi e Potentati ...”1 ..... alimentano l'idea di tradire Cleopatra, di far ammutinare la nave e di ricondurre ... sconvolgimento libidico ad opera di Esra (madre di Afra), la fuga e, forse, la salvezza ...

  9. La necropoli neolitica a domus de janas di S. Pietro di Sorres in Comune di Borutta - Sassari

    Directory of Open Access Journals (Sweden)

    Pier Paolo Soro

    2009-05-01

    Full Text Available La necropoli di Sorres si trova nel territorio del Comune di Borutta in provincia di Sassari. E’ ubicata lungo il versante SE del colle di Sorres, sul quale sorge imponente la chiesa in stile romanico di San Pietro di Sorres (XI-XII sec. sede dell’antica diocesi medievale. La necropoli è composta attualmente da cinque tombe a grotticella artificiale del tipo a domus de janas, scavate nella roccia calcara durante il neolitico recente ed in uso per tutto l’eneolitico. Si presume che fosse l’area sepolcrale dell’insediamento in grotta di Ulàri, una cavità carsica di notevoli dimensioni il cui ingresso si apre lungo il versante Nord del colle; la grotta ha restituito testimonianze archeologiche che vanno dal neolitico media fino al medioevo. La necropoli di Sorres, sebbene sia stata rimaneggiata nella forma degli ambienti ipogei e nella destinazione d’uso, costituisce una delle principali testimonianze del capillare tessuto insediativo del territorio del nord Sardegna.

  10. Electrical velocimetry for non-invasive monitoring of the closure of the ductus arteriosus in preterm infants.

    Science.gov (United States)

    Rodríguez Sánchez de la Blanca, Ana; Sánchez Luna, M; González Pacheco, N; Arriaga Redondo, M; Navarro Patiño, N

    2018-02-01

    Closure of a patent ductus arteriosus (PDA) in preterm infants modifies cardiac output and induces adaptive changes in the hemodynamic situation. The present study aims to analyze those changes, through a non-invasive cardiac output monitor based on blood electrical velocimetry, in preterm babies. A prospective observational study of preterm infants with a gestational age of less than 28 weeks, and a hemodynamic significant PDA, requires intravenous ibuprofen or surgical closure. All patients were monitored with electrical velocimetry before treatment and through the following 72 h. Two groups were defined, ibuprofen and surgical closure. Variations of cardiac output were analyzed from the basal situation and at 1, 8, 24, 48, and 72 h on each group. During a 12-month period, 18 patients were studied. The median gestational age in the ibuprofen group (12/18) was 26 +5  weeks (25 +5 -27 +3 ) with a median birth weight of 875 (670-1010) g. The cardiac output index (CI) value was 0.29 l/kg/min (0.24-0.34). Among the patients with confirmed ductus closure (50%), a significant CI decrease was shown (0.24 vs 0.29 l/kg/min; P 0.03) after 72 h (three ibuprofen doses). A statistically significant decrease in systolic volume (SVI) was found: 1.62 vs 1.88 ml/kg, P 0.03 with a decrease in contractility (ICON), 85 vs 140, P 0.02. The gestational age in the surgical group (6/18) was 25 +2  weeks (24-26 +3 ) with a median weight of 745 (660-820) g. All patients in this group showed a decrease in the immediate postoperative CI (1 h after surgery) 0.24 vs 0.30 l/kg/min, P 0.05, and a significant decrease in contractility (ICON 77 vs 147, P 0.03). In addition, a no statistically significant decrease in SVI (1.54 vs 1.83 ml/kg, P 0.06), as well as an increase in systemic vascular resistance (10,615 vs 8797 dyn/cm 2 , P 0.08), were detected. This deterioration was transient without significant differences in the remaining periods of time evaluated. The surgical closure

  11. PhD Dissertations Tesi di dottorato

    Directory of Open Access Journals (Sweden)

    Redazione Reti Medievali (a cura di

    2004-06-01

    Full Text Available

    Report of PhD Dissertations.

    Francesco Barone

    Istituzioni, società ed economia a Catania nel tardo medioevo (XIV-XV secolo, Tesi di dottorato in Storia medievale (XVI ciclo, Università degli Studi di Firenze, 2004

     

    Laura Berti Ceroni

    Il territorio e le strutture di Cesarea e Classe tra tarda antichità e alto medioevo in rapporto con Ravenna, Tesi di dottorato di ricerca in Storia e Informatica, Università degli studi di Bologna, 2002-2003.

     

    Marco Bicchierai

    Poppi dalla signoria dei conti Guidi al vicariato del Casentino (1360-1480, Tesi di dottorato in Storia medievale (XIV ciclo, Università degli Studi di Firenze, 2004

     

    Emanuela Garimberti

    Spatiosa ad habitandum loca. Luoghi e identità nella Historia Langobardorum di Paolo Diacono, Tesi di dottorato in Storia medievale (XV ciclo, Università degli Studi di Bologna, 2004

     

    Lorenzo Tanzini

    Sistemi normativi e pratiche istituzionali a Firenze dalla fine del XIII all’inizio del XV secolo, Tesi di dottorato di ricerca in Storia medievale (XVI ciclo, Università degli Studi di Firenze, 2004

     

    Stefania Tarquini

    Pellegrinaggio e asseto urbano di Roma, Tesi di dottorato di ricerca in Storia dei centri, delle vie e della cultura dei pellegrinaggi nel Medioevo euro mediterraneo (XV ciclo, Università degli studi di Lecce, 2003

    Segnalazione di tesi di dottorato.

    Francesco Barone

    Istituzioni, società ed economia a Catania nel tardo medioevo (XIV-XV secolo, Tesi di dottorato in Storia medievale (XVI ciclo, Università degli Studi di Firenze, 2004

     

    Laura Berti Ceroni

  12. Il loricato acefalo di Rusellae (Roselle, GR: una proposta di identificazione

    Directory of Open Access Journals (Sweden)

    Eleonora Romanò

    2013-07-01

    Full Text Available Lo studio è incentrato sul tentativo di comprendere la scena presente sulla lorica di una statua acefala di probabile fine età claudia rinvenuta nell'area archeologica di Rusellae (Roselle, GR all'interno di un edificio connesso al culto imperiale. La decorazione analizzata è composta da diversi elementi: un trofeo di armi ed un'aquila in posizione pressocchè centrale, ai loro lati si dispongono figure umane interpretabili come barbari e per le quali si propone l'identificazione con il britanno Caratacus accompagnato dai suoi familiari mentre rivolge una supplica di liberazione al Senato ed all'imperatore Claudio, secondo l'episodio riportato negli Annales di Tacito (12.33-40.

  13. Analisi dell’utilizzo di Twitter nella costruzione di un seminario sperimentale

    Directory of Open Access Journals (Sweden)

    Wolfgang Reinhardt

    2013-03-01

    Full Text Available Nonostante i massicci cambiamenti sociali e tecnologici che si sono verificati a causa del Web negli ultimi anni, i corsi universitari spesso enfatizzano metodi di insegnamento da tempo consolidati e basati su strumenti di apprendimento e risorse tradizionali. Durante tali corsi gli studenti spesso acquisiscono una conoscenza che non è aggiornata e che è lontana da un apprendimento realistico, basato su problemi. L'uso di strumenti e metodi più recenti spesso rimane fuori dalla padronanza degli studenti. In questo contributo si descrive brevemente l’impostazione sperimentale di un seminario in due università tedesche dove l’uso di Social Media per la comunicazione e la collaborazione è stato saldamente integrato alla progettazione di un percorso di apprendimento formale. Si illustra, inoltre, l'utilizzo di Twitter durante il seminario, usando metodologie riprese dalla Social Network Analysis.

  14. Macchine per giuoco nella proposta di Leopardi

    Directory of Open Access Journals (Sweden)

    Laura Neri

    2017-06-01

    Full Text Available Un’operetta morale di Leopardi, la Proposta di premi fatta dall’Accademia dei Sillografi, adotta il linguaggio tecnico di un bando di concorso per proporre tre premi agli inventori di tre macchine umane perfette: l’amicizia, la magnanimità, la fedeltà coniugale sono gli obiettivi delle invenzioni scientifiche. Il tono serio cela in realtà la  polemica contro l’antropocentrismo e soprattutto contro l’ottimismo del suo tempo.  One of Leopardi’s Operette morali, Proposta di premi fatta dall’Accademia dei Sillografi, adopts the gergon of a competition notice to propose three prizes to the inventors of three perfect human machines: friendship, magnanimity, conjugal fidelity are the aims of scientific inventions. The serious tone really conceals the controversy against anthropocentrism and above all against the optimism of its time.

  15. Analisi dell'efficacia di un programma di prevenzione secondaria del carcinoma orale

    Directory of Open Access Journals (Sweden)

    S. Iannazzo

    2003-05-01

    Full Text Available

    In Italia i carcinomi del cavo orale (KCO sono diagnosticati
    prevalentemente al II-IV stadio TNM con conseguenti basse sopravvivenza a 5 anni e qualità della vita. Una maggior frequenza di diagnosi allo stadio I porterebbe a migliorare ampiamente i valori medi dei suddetti parametri.
    Scopo del presente lavoro è stato valutare l’efficacia di un programma di prevenzione secondaria del KCO in termini di aumento di diagnosi allo stadio I e di vite salvate.

    Abbiamo stimato la prevalenza di casi istopatologicamente
    accertati (livello C3 di leucoplachia, principale lesione precancerosa del KCO, nella ASL/RMA come prodotto tra la prevalenza stimata di leucoplachia diagnosticata clinicamente (livello C2 (2989,2Ĩ13077,7 e la proporzione, scelta arbitrariamente, di C3 tra i C2 (0,50.

    Tenendo presente che nel campione studiato nella ASL/RMA la proporzione di KCO allo stadio I tra i C3 era 0,03, abbiamo stimato il numero di KCO.

    Abbiamo stimato quanti KCO verrebbero diagnosticati allo stadio I se venisse attuato un programma di prevenzione secondaria, considerando diversi livelli di compliance, e sulla base di una sopravvivenza media a 5 anni, in Italia, del 53% per tutti gli stadi e del 79% per i KCO allo stadio I, abbiamo calcolato il numero di vite salvate. I valori sono stati espressi come IC95.

    Le prevalenze di leucoplachia C3 e KCO sono risultate,
    rispettivamente, 1494,6Ĩ6538,8 e 44,8Ĩ196,2. Con compliance del 10%, 40% e 75% verrebbero diagnosticati, rispettivamente, 4,5Ĩ19,6, 17,9Ĩ78,5 e 33,6Ĩ147,2 casi di KCO e le vite salvate sarebbero 1,1Ĩ5,1, 4,6Ĩ20,4 e 8,7Ĩ38,3 rispettivamente.
    In termini di vite salvate i dati evidenziano la necessita di attuare programmi di screening del KCO, anche nell' eventualità di uno scarso coinvolgimento della popolazione a rischio.

  16. Fleeing War. Due strategie di diserzione letteraria:I parenti del Sud di Carlo Montella e Going After Cacciato di Tim O’Brien

    Directory of Open Access Journals (Sweden)

    Giulio Segato

    2014-10-01

    Full Text Available Il saggio indaga due diverse strategie di diserzione rappresentate in due romanzi di guerra: I parenti del sud di Carlo Montella e Going After Cacciato di Tim O’Brien. Nelle due opere analizzate la diserzione sembra essere collegata al conflitto che fa da sfondo al romanzo. Nel libro di Montella,il protagonista, ancora obnubilato dalle dottrine tautologiche fasciste, qualche settimana dopo l’armistizio di Cassibile decide di disertare e di fuggire nella villa di un’anziana parente, con lo scopo di rinsavire dall’ideologia del regime. Nel romanzo di O’Brien, invece, la fuga messa in scena dall’autore sembra avere gli stessi tratti grotteschi e assurdi del conflitto in cui è stato catapultato il protagonista,la Guerra del Vietnam.

  17. Fasilitas Wisata Kuliner Solo di Solo Baru

    OpenAIRE

    Oetomo, Anthony

    2014-01-01

    Fasilitas Wisata Kuliner Solo di Solo Baru” ini merupakan fasilitas yang memberikan wadah bagi berbagai macam kuliner yang terdapat di kota Solo. Dengan demikian tempat ini akan menjadi tujuan wisata kuliner bagi masyarakat di Solo maupun dari luar Solo untuk menikmati dan memperkenalkan berbagai macam kuliner yang ada kepada masyarakat, dan menyediakan fasilitas bagi para wisatawan yang hanya memiliki waktu terbatas untuk menikmati berbagai macam kuliner Solo. Proyek ini menyediakan galeri d...

  18. STRATEGI MARKET ENTRY CONVENIENCE STORE DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Respati Wulandari

    2017-04-01

    Full Text Available Penelitian ini bertujuan untuk menganalisa dan melihat strategi yang digunakan pada Convenience Store di Indonesia dengan mengambil 7-Eleven sebagai sumber field study dengan metode orientasi pasar. Pengaruh lifestyle menjadi indikator penunjang dalam perkembangan 7-Eleven ddengan menerapkan beberapa strategi yang mengena di market Indonesia, terutama bagi kalangan muda dimana diketahui memiliki indikasi terpenting dalam siklus lifestyle di Indonesia. Tujuan tercapai dengan mengetahui penerapan strategi yang digunakan sehingga dapat diterapkan dalam menjalankan strategi bisnis pada Convenience Store

  19. Kajian Pengembangan Mebel Rotan di Sumbawa Barat

    OpenAIRE

    Edi Eskak

    2016-01-01

    ABSTRAKRotan merupakan hasil hutan yang melimpah di Sumbawa Barat sehingga mempunyai potensi yang besar untuk pengembangan industri mebel rotan. Di Sumbawa Barat saat ini tidak terdapat industri pengolahan rotan asalan menjadi iratan dan pitrit, sebagai bahan anyaman untuk mebel. Tujuan kajian ini adalah untuk mencari solusi pengembangan mebel rotan di Sumbawa Barat yang bahan bakunya masih berupa rotan asalan yaitu berupa rotan batangan menjadi produk mebel. Metode yang digunakan yaitu deskr...

  20. La ristorazione nelle case di cura convenzionate di una ASL romana. Verifica dell'adeguatezza nutrizionale

    OpenAIRE

    Cairella, G.; Marchetti, A.; Rebella, V.; Sonni, L.; Ciaralli, F.

    2012-01-01

    Obiettivi: valutazione dell’adeguatezza nutrizionale dei menù di case di cura convenzionate e formulazione di raccomandazioni finalizzate al raggiungimento della sicurezza nutrizionale dell’utente ricoverato.

    Metodi: alle Direzioni Sanitarie delle case di cura convenzionate sono stati richiesti i menu invernali ed estivi del vitto comune e speciale. La valutazione giornaliera media dell’energia totale, l’appo...

  1. Matrimonio omosessuale e pubblico ufficiale: una nuova forma di obiezione di coscienza?

    Directory of Open Access Journals (Sweden)

    Ludovica Decimo

    2015-10-01

    SOMMARIO: 1. La difesa dei valori culturali e religiosi attraverso il diritto all’obiezione di coscienza - 2. I casi di obiezione di coscienza sulle unioni omosessuali: uno sguardo d’insieme oltre i confini nazionali - 3. Il matrimonio omosessuale e il pubblico ufficiale nell’ordinamento giuridico italiano - 4. Lo scudo dell’obiezione di coscienza: un’opzione possibile per il pubblico ufficiale?

  2. Analisis Faktor-Faktor Yang Mempengaruhi Konsumen Dalam Memutuskan Untuk Menginap Di Green Hotel Di Surabaya

    OpenAIRE

    Loppies, Alfredo Karsten; Nugroho, Steven Adi; Jokom, Regina

    2016-01-01

    Penelitian ini dilakukan untuk mengetahui faktor – faktor yang mempengaruhi konsumen dalam memutuskan untuk menginap di green hotel di Surabaya. Populasi adalah seluruh konsumen yang pernah menginap di hotel yang tergolong green hotel di Surabaya minimal sekali dalam kurun waktu 6 bulan terakhir dengan sampel penelitian berjumlah 168 responden. Teknik analisa yang digunakan dalam penelitian ini adalah analisa faktor untuk mereduksi sejumlah faktor internal dan eksternal yang mempengaruhi per...

  3. Sviluppo e valutazione di test diagnostici per la sierodiagnosi di brucellosi suina

    Directory of Open Access Journals (Sweden)

    Tiziana Di Febo

    2012-06-01

    Full Text Available Sono stati sviluppati una ELISA competitiva (c-ELISA, una ELISA indiretta (i-ELISA e un test immunologico DELFIA (Dissociation-Enhanced Lanthanide Fluorescence Immunoassay per la ricerca di anticorpi verso Brucella suis in sieri di maiale e cinghiale. I tre test prevedono l’utilizzo di un anticorpo monoclonale (MAb 4B5A verso l’LPS di Brucella (c-ELISA e DELFIA e di un anticorpo monoclonale (MAb 10C2G5 verso le IgG suine (i-ELISA. La specificità (Sp e la sensibilità (Se dei tre test sono le seguenti: per la c-ELISA Se e Sp = 100% con un valore di cut-off pari al 61.0% (B/B0%; per la i-ELISA Sp = 99.1% e Se = 100% con un valore di cut-off di 21.7% (PP%; per il DELFIA Sp = 91.0% e Se = 75% ponendo il valore di cut-off al 37.0% (B/B0%. Inoltre sono state valutate le performance, nei confronti di sieri suini, di un test FPA (Fluorescence Polarization Assay commerciale sviluppato per la ricerca di anticorpi anti-Brucella in sieri bovini; la specificità e la sensibilità ottenute sono entrambe del 100% al valore di cut-off di 99.5 (mP. Questi risultati suggeriscono che la combinazione di c-ELISA, i-ELISA e FPA può essere utilizzata per migliorare la diagnosi di brucellosi suina.

  4. Fenologia dei Chirotteri nella grotta di Onferno

    Directory of Open Access Journals (Sweden)

    Massimo Bertozzi

    2003-10-01

    Full Text Available Con le sue 11 specie e le oltre 6000 presenze di Chirotteri la Riserva naturale orientata di Onferno è certamente un punto di notevole interesse nel patrimonio naturale italiano. A seguito dei piani di indagine e di sorveglianza posti in essere fin dalla sua creazione nel 1992 da parte della gestione della Riserva e soprattutto grazie al progetto LIFE in corso, si riassumono qui i principali tratti fenologci delle diverse specie nella cavità. Il sistema ipogeo è altamente differenziato topografica e in termini di microclima, come rilevato dal sistema di monitoraggio presente. Da Dicembre inizia il periodo più tipicamente invernale con rapido abbandono della cavità principale da parte dei miniotteri. Vi rimangono poche decine di esemplari e altrettanti rinolofidi delle diverse specie. Tale situazione si prolunga con alcune piccole variazioni fino a Marzo. Al cambio di stagione i miniotteri si muovono dai rifugi posti soprattutto in un tunnel a S. Marino (circa 11 km in linea d?aria a temperatura tra i 3 e 5 °C per tornare nel tratto principale a circa 7°C. I rinolofidi mantengono le posizioni e i numeri precedenti. Con Aprile il gruppo dei miniotteri, oramai completo o quasi, si sposta nella Sala Guano o rimane in vari ambiti del percorso principale. I rinolofidi appaiono in movimento ma il loro numero diminuisce almeno dalle zone di controllo. A Maggio compaiono anche i grandi vespertili già aggregati al grande gruppo dei miniotteri che spesso si presenta in contingenti suddivisi in vari ambiti della grotta. Non si ritrovano più rinolofi maggiori, mentre euryale e minore raggiungono le sale più calde e secche. Con Giugno i contingenti si concentrano nella grande sala ?Quarina? per formare nella seconda metà la colonia riproduttiva. Dal 15 circa iniziano i parti in tutte le specie. Nel Miniottero si registrano scarti di almeno una settimana tra l?avvio della riproduzione e le ultime nascite. Tutto Luglio è speso nella crescita dei

  5. Migrazioni di archetipi: tradizioni e rapimenti

    Directory of Open Access Journals (Sweden)

    Giulia Valsecchi

    2014-07-01

    Full Text Available Quel che resta di una trasmissione orale o scritta sono tracce multiple e mai estinte. I segni e i simboli che la rinnovano, secondo influsso e revisione dei confini di tradizione, traduzione o plagio, sono oggetto del volume collettaneo Archetypes in Literatures and Cultures – Cultural and Re- gional Studies a cura di Rahilya Geybullayeva (Baki Slavian Universiteti, Azerbaijan. Un’analisi a più voci degli attraversamenti identitari per migrazioni di archetipi nello spazio-tempo delle lettera- ture ed epopee.

  6. Effetti di serie: semiotica della dipendenza televisiva

    Directory of Open Access Journals (Sweden)

    Valentina Pisanty

    2016-06-01

    Full Text Available Nelle conversazioni quotidiane e in rete si discute molto della dipendenza da serie televisive, con particolare riferimento alle serie continue di ultima generazione (tra cui Game of Thrones, Homeland, House of Cards e simili, le quali sembrano incoraggiare il cosiddetto binge-watching più di qualsiasi altra fiction precedente. Molti commentatori paragonano questo fenomeno alla tossicodipendenza, e una recente ricerca psicologica (Hoon Hi Sung, Eun Yeon Kang, Wei-Na Lee 2015 collega la dipendenza da serie alla depressione. Ma quanto è accurato (o invece metaforico l’accostamento della compulsione seriale alle forme più tradizionali di intossicazione? Questo articolo analizza la vasta fenomenologia delle dipendenze da serie da un prospettiva semiotica, con il proposito di distinguere tra diversi stili di fruizione immersiva: dalle maratone solitarie e onnivore che effettivamente possono suscitare sentimenti individuali di frustrazione e di inadeguatezza, all’intensa attività sociale che viceversa circonda alcuni specifici culti televisivi. Sino a che punto è possibile ascrivere una simile gamma di atteggiamenti interpretativi alle strutture stesse dei testi, per esempio in rapporto alle trame, all’architettura dei mondi narrativi e alla costruzione di personaggi con cui gli spettatori possono identificarsi? E quali effetti producono le frequenti e prolungate immersioni nei mondi seriali sulla percezione collettiva del mondo reale?

  7. Il controllo di gestione e operativo delle commesse per una impresa di costruzioni: nuovo impianto di trattamento e recupero di rifiuti urbani.

    Directory of Open Access Journals (Sweden)

    Matteo Camprini

    2013-10-01

    Full Text Available Il mercato delle costruzioni in Italia soffre problemi di maturità da molto tempo. Dagli anni ’90, infatti, per superare i fatti di tangentopoli venne riformata la legislazione dei lavori pubblici per giungere a livelli di competizione maggiori e più simili a quelli esistenti in Europa.  In questo contesto le imprese che per la loro struttura culturale, organizzativa e produttiva mostravano maggiore sensibilità a tali aspetti avviarono processi di formazione e riorganizzazione introducendo specifiche procedure mirate alla gestione completa dei progetti trasformandosi così da imprese di sola produzione a imprese operanti per progetti.La presente memoria vuole descrivere il sistema di gestione attuato, le modifiche ed i miglioramenti che si sono susseguiti nel tempo,  la sua struttura organizzativa e gli strumenti di lavoro messi a disposizione.A conclusione verrà illustrata l’applicazione al caso concreto della costruzione del nuovo impianto di trattamento e recupero di rifiuti urbani.

  8. Pantani di Marco Martinelli: una narrazione polifonica

    Directory of Open Access Journals (Sweden)

    Franco Nasi

    2014-05-01

    Full Text Available In questo articolo si analizza il testo drammaturgico Pantani di Marco Martinelli, una veglia epica teatrale di uno dei più noti eroi dello sport italiano degli ultimi anni. Il dramma rilegge anche la storia di Pantani e ricostruisce gli strani avvenimenti che portarono alla sospensione, alla estromissione del ciclista dal Giro d’Italia nel 1999, e in seguito alla sua profonda crisi psicologica e tragica morte in solitudine in un hotel, a soli 34 anni. Oltre alle modalità proprie della veglia rituale, il dramma utilizza anche i metodi del processo giudiziario, e offre testimonianze dettagliate che conducono a una riflessione critica sulla società italiana negli anni del potere politico di Berlusconi e della sua filosofia del consumismo. I tre diversi generi della retorica classica (epidittico, giudiziario e deliberativo si mescolano in questa complessa tessitura teatrale. Coniugando informazioni (processo e rito (veglia, Martinelli riesce a fondere la tragedia greca (forma mimetica e corale e il moderno teatro di narrazione (forma diegetica monologante. Combinando assieme scene intensamente drammatiche, ricordi di imprese sportive epiche, passaggi giocosi e parodici, e giustapponendo vari stili e registri (giornalistico, lirico, parodico, elegiaco, Martinelli crea momenti di forte “straniamento” e sorpresa, e rende particolarmente efficace il rito funebre, la ricostruzione storica della tragica vicenda di Pantani e la critica all’ideologia che ha dominato l’Italia negli anni di Berlusconi.

  9. Riconoscimento in Italia di sentenza straniera di adozione da parte di un single con effetti legittimanti: il Tribunale per i minorenni di Bologna supera la Cassazione

    Directory of Open Access Journals (Sweden)

    Maria Astone

    2015-01-01

    Full Text Available L’adozione del minore da parte di una persona singola torna all’attenzione della giurisprudenza che, ancora una volta, viene investita della questione relativa al riconoscimento ed efficacia di una sentenza straniera di adozione con effetti legittimanti. Tribunale per i minorenni Bologna 17 aprile 2013 si è trovato ad affrontare il caso di un genitore single, non coniugato, cittadino italiano, che, avendo ottenuto negli Stati Uniti d’America, una sentenza di adozione di minore, ne ha chiesto il riconoscimento. Due i problemi sottoposti al Tribunale: il primo, relativo alla competenza territoriale del giudice adito, positivamente risolto ai sensi degli articoli 40 e 41 della legge n. 218 del 1995 ; il secondo, invece, più complesso, legato agli effetti che il riconoscimento della sentenza avrebbe avuto in Italia. In particolare, per il giudice di merito si è trattato di stabilire se il provvedimento straniero di adozione potesse produrre anche in Italia gli effetti legittimanti dell’adozione ordinaria dei minori, già prodottisi negli Stati Uniti d’America.

  10. Qualche considerazione sulle "Pensées" di Montesquieu

    Directory of Open Access Journals (Sweden)

    Fabiana Fraulini

    2011-02-01

    Full Text Available The paper examines the the books: Montesquieu, "Pensieri diversi", a cura di D. Felice, Napoli, Liguori, 2010; Montesquieu, "Riflessioni e pensieri inediti (1716-1755", tr. it. di L. Ginzburg, intr. di D. Felice, Bologna, CLUEB, 2010.

  11. Experimental investigations on the fluid-mechanics of an electrospun heart valve by means of particle image velocimetry.

    Science.gov (United States)

    Del Gaudio, Costantino; Gasbarroni, Pier Luca; Romano, Giovanni Paolo

    2016-12-01

    End-stage failing heart valves are currently replaced by mechanical or biological prostheses. Both types positively contribute to restore the physiological function of native valves, but a number of drawbacks limits the expected performances. In order to improve the outcome, tissue engineering can offer an alternative approach to design and fabricate innovative heart valves capable to support the requested function and to promote the formation of a novel, viable and correctly operating physiological structure. This potential result is particularly critical if referred to the aortic valve, being the one mainly exposed to structural and functional degeneration. In this regard, the here proposed study presents the fabrication and in vitro characterization of a bioresorbable electrospun heart valve prosthesis using the particle image velocimetry technique either in physiological and pathological fluid dynamic conditions. The scaffold was designed to reproduce the aortic valve geometry, also mimicking the fibrous structure of the natural extracellular matrix. To evaluate its performances for possible implantation, the flow fields downstream the valve were accurately investigated and compared. The experimental results showed a correct functionality of the device, supported by the formation of vortex structures at the edge of the three cusps, with Reynolds stress values below the threshold for the risk of hemolysis (which can be comprised in the range 400-4000N/m(2) depending on the exposure period), and a good structural resistance to the mechanical loads generated by the driving pressure difference. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Parallel computing of a digital hologram and particle searching for microdigital-holographic particle-tracking velocimetry

    International Nuclear Information System (INIS)

    Satake, Shin-ichi; Kanamori, Hiroyuki; Kunugi, Tomoaki; Sato, Kazuho; Ito, Tomoyoshi; Yamamoto, Keisuke

    2007-01-01

    We have developed a parallel algorithm for microdigital-holographic particle-tracking velocimetry. The algorithm is used in (1) numerical reconstruction of a particle image computer using a digital hologram, and (2) searching for particles. The numerical reconstruction from the digital hologram makes use of the Fresnel diffraction equation and the FFT (fast Fourier transform),whereas the particle search algorithm looks for local maximum graduation in a reconstruction field represented by a 3D matrix. To achieve high performance computing for both calculations (reconstruction and particle search), two memory partitions are allocated to the 3D matrix. In this matrix, the reconstruction part consists of horizontally placed 2D memory partitions on the x-y plane for the FFT, whereas, the particle search part consists of vertically placed 2D memory partitions set along the z axes.Consequently, the scalability can be obtained for the proportion of processor elements,where the benchmarks are carried out for parallel computation by a SGI Altix machine

  13. Multiple Δt strategy for particle image velocimetry (PIV) error correction, applied to a hot propulsive jet

    International Nuclear Information System (INIS)

    Nogueira, J; Lecuona, A; Nauri, S; Legrand, M; Rodríguez, P A

    2009-01-01

    PIV (particle image velocimetry) is a measurement technique with growing application to the study of complex flows with relevance to industry. This work is focused on the assessment of some significant PIV measurement errors. In particular, procedures are proposed for estimating, and sometimes correcting, errors coming from the sensor geometry and performance, namely peak-locking and contemporary CCD camera read-out errors. Although the procedures are of general application to PIV, they are applied to a particular real case, giving an example of the methodology steps and the improvement in results that can be obtained. This real case corresponds to an ensemble of hot high-speed coaxial jets, representative of the civil transport aircraft propulsion system using turbofan engines. Errors of ∼0.1 pixels displacements have been assessed. This means 10% of the measured magnitude at many points. These results allow the uncertainty interval associated with the measurement to be provided and, under some circumstances, the correction of some of the bias components of the errors. The detection of conditions where the peak-locking error has a period of 2 pixels instead of the classical 1 pixel has been made possible using these procedures. In addition to the increased worth of the measurement, the uncertainty assessment is of interest for the validation of CFD codes

  14. Experimental assessment of valve performance in healthy and diseased right ventricular outflow tracts using magnetic resonance velocimetry

    Science.gov (United States)

    Schiavone, Nicole; Elkins, Christopher; McElhinney, Doff; Eaton, John K.; Marsden, Alison

    2017-11-01

    Tetralogy of Fallot (ToF), the most common type of cyanotic congenital heart defect, affects 1 in every 2500 newborns annually and typically requires surgical repair of the right ventricular outflow tract (RVOT) and placement of an artificial pulmonary valve. All artificial valves are subject to dysfunction, but their longevity is highly variable. Clinical observation reveals large variations in RVOT anatomy in ToF patients, which may affect longevity. This work aims to experimentally assess the performance of artificial pulmonary valves in anatomically realistic healthy and diseased RVOT geometries using magnetic resonance velocimetry (MRV). With MRV, we can capture 3D, three-component, phase-averaged velocity fields in 3D printed RVOT geometries. The experiment is designed to ensure physiological flow rate and pressure waveforms, while the RVOT geometries are based on anatomies seen clinically in ToF patients. Two models are used in the current work: an idealized RVOT based on healthy subjects aged eleven to thirteen and a diseased geometry with a dilation of 150% in vessel diameter downstream of the pulmonary valve. We will also present preliminary rigid-wall blood flow simulations in each model, towards the ultimate goal of experimental validation of valve simulations.

  15. Structure of a swirl-stabilized spray flame by imaging, laser Doppler velocimetry, and phase Doppler anemometry

    Science.gov (United States)

    Edwards, C. F.; Rudoff, R. C.

    1991-01-01

    Data are presented which describe the mean structure of a steady, swirl-stabilized, kerosene spray flame in the near-injector region of a research furnace. The data presented include ensemble-averaged results of schlieren, luminosity, and extinction imaging, measurement of the gas phase velocity field by laser Doppler velocimetry, and characterization of the condensed phase velocity by phase Doppler anemometry. The results of these studies define six key regions in the flame: the dense spray region; the rich, two-phase, fuel jet; the main air jet; the internal product recirculation zone; the external product recirculation zone; and the gaseous diffusion flame zone. The first five of these regions form a conical mixing layer which prepares the air and fuel for combustion. The air and fuel jets comprise the central portion of this mixing layer and are bounded on either side by the hot product gases of the internal and external recirculation zones. Entrainment of these product gases into the air/fuel streams provides the energy required to evaporate the fuel spray and initiate combustion. Intermittency of the internal recirculation and spray jet flows accounts for unexpected behavior observed in the aerodynamics of the two phases. The data reported herein are part of the database being accumulated on this spray flame for the purpose of detailed comparison with numerical modeling.

  16. Beam stability and warm-up effects of Nd:YAG lasers used in particle image velocimetry

    International Nuclear Information System (INIS)

    Grayson, K; De Silva, C M; Hutchins, N; Marusic, I

    2017-01-01

    The characteristics and causes of Nd:YAG laser warm-up transients and steady state beam stability effects are investigated in this study. Dynamic laser performance has a particularly noticeable impact on particle image velocimetry (PIV) and other laser-based flow visualisation techniques, where changes in beam pointing can influence the overlap between laser light sheets and thereby degrade the correlation of PIV image pairs. Despite anecdotal knowledge or experience of laser warm-up effects, they have not been formally documented or quantified to date for PIV applications. In this study, the nature of these laser transients are analysed and compared among a selection of typical PIV laser equipment. An investigation into the cause of these transients during the laser warm-up sequence is also presented. Furthermore, the degree of dual cavity transient coupling within a PIV laser system is analysed to determine a practical limit to the laser light sheet overlap that can be expected from PIV experiments. Finally, the results from this study inform a series of recommendations for PIV best practice, which aim to minimise the impact of laser transients on experimental data. (paper)

  17. Particle imaging velocimetry evaluation of intracranial stents in sidewall aneurysm: hemodynamic transition related to the stent design.

    Science.gov (United States)

    Bouillot, Pierre; Brina, Olivier; Ouared, Rafik; Lovblad, Karl-Olof; Farhat, Mohamed; Pereira, Vitor Mendes

    2014-01-01

    We investigated the flow modifications induced by a large panel of commercial-off-the-shelf (COTS) intracranial stents in an idealized sidewall intracranial aneurysm (IA). Flow velocities in IA silicone model were assessed with and without stent implantation using particle imaging velocimetry (PIV). The use of the recently developed multi-time-lag method has allowed for uniform and precise measurements of both high and low velocities at IA neck and dome, respectively. Flow modification analysis of both regular (RSs) and flow diverter stents (FDSs) was subsequently correlated with relevant geometrical stent parameters. Flow reduction was found to be highly sensitive to stent porosity variations for regular stents RSs and moderately sensitive for FDSs. Consequently, two distinct IA flow change trends, with velocity reductions up to 50% and 90%, were identified for high-porosity RS and low-porosity FDS, respectively. The intermediate porosity (88%) regular braided stent provided the limit at which the transition in flow change trend occurred with a flow reduction of 84%. This transition occurred with decreasing stent porosity, as the driving force in IA neck changed from shear stress to differential pressure. Therefore, these results suggest that stents with intermediate porosities could possibly provide similar flow change patterns to FDS, favourable to curative thrombogenesis in IAs.

  18. Low Reynolds number airfoil aerodynamic loads determination via line integral of velocity obtained with particle image velocimetry

    Energy Technology Data Exchange (ETDEWEB)

    Lee, T.; Su, Y.Y. [McGill University, Department of Mechanical Engineering, Montreal, QC (Canada)

    2012-11-15

    The small magnitude lift forces generated by both a NACA 0012 airfoil and a thin flat plate at Re = 29,000 and 54,000 were determined through the line integral of velocity, obtained with particle image velocimetry, via the application of the Kutta-Joukowsky theorem. Surface pressure measurements of the NACA0012 airfoil were also obtained to validate the lift coefficient C{sub l}. The bound circulation was found to be insensitive to the size and aspect ratio of the rectangular integration loop for pre-stall angles. The present C{sub l} data were also found to agree very well with the surface pressure-determined lift coefficient for pre-stall conditions. A large variation in C{sub l} with the loop size and aspect ratio for post-stall conditions was, however, observed. Nevertheless, the present flat-plate C{sub l} data were also found to collectively agree with the published force-balance measurements at small angles of attack, despite the large disparity exhibited among the various published data at high angles. Finally, the ensemble-averaged wake velocity profiles were also used to compute the drag coefficient and, subsequently, the lift-to-drag ratio. (orig.)

  19. Comparison of particle image velocimetry and phase contrast MRI in a patient-specific extracardiac total cavopulmonary connection.

    Science.gov (United States)

    Kitajima, Hiroumi D; Sundareswaran, Kartik S; Teisseyre, Thomas Z; Astary, Garrett W; Parks, W James; Skrinjar, Oskar; Oshinski, John N; Yoganathan, Ajit P

    2008-08-01

    Particle image velocimetry (PIV) and phase contrast magnetic resonance imaging (PC-MRI) have not been compared in complex biofluid environments. Such analysis is particularly useful to investigate flow structures in the correction of single ventricle congenital heart defects, where fluid dynamic efficiency is essential. A stereolithographic replica of an extracardiac total cavopulmonary connection (TCPC) is studied using PIV and PC-MRI in a steady flow loop. Volumetric two-component PIV is compared to volumetric three-component PC-MRI at various flow conditions. Similar flow structures are observed in both PIV and PC-MRI, where smooth flow dominates the extracardiac TCPC, and superior vena cava flow is preferential to the right pulmonary artery, while inferior vena cava flow is preferential to the left pulmonary artery. Where three-component velocity is available in PC-MRI studies, some helical flow in the extracardiac TCPC is observed. Vessel cross sections provide an effective means of validation for both experiments, and velocity magnitudes are of the same order. The results highlight similarities to validate flow in a complex patient-specific extracardiac TCPC. Additional information obtained by velocity in three components further describes the complexity of the flow in anatomic structures.

  20. Micro-PIV (micro particle image velocimetry) visualization of red blood cells (RBCs) sucked by a female mosquito

    International Nuclear Information System (INIS)

    Kikuchi, K; Mochizuki, O

    2011-01-01

    A mosquito's pump is a highly effective system in the small suction domain. To understand a mosquito's blood suction mechanism, we analysed the characteristics of red blood cells (RBCs) in human blood during and after suction by a female mosquito. Focussing on the flow patterns of the RBCs in human blood being sucked by a mosquito, we visualized blood flow by using a micro-particle image velocimetry (μ-PIV) system, which combines an optical microscope and a PIV method. In an ex vivo experiment, a female mosquito was supplied diluted blood at the tip of the proboscis. We examined the blood flow around the tip of the proboscis and observed that RBCs were periodically sucked towards a hole around the tip. The sucked RBCs then homogeneously flowed parallel to the inner surface of the proboscis without adhering to the wall. Furthermore, using a bioelectric recording system, we directly measured electrical signals generated during suction by the pump muscles located in the mosquito's head. We found that the electrical signal power was synchronized with the acceleration of the RBCs in the sucking phase. A histological stain method was adapted for the observation of the form and internal structure of RBCs in the mosquito. Although the blood flow analysis revealed that the RBCs underwent shear stress during suction, RBCs in the mosquito's stomach maintained their original shape

  1. Wall shear stress measurement of near-wall flow over inclined and curved boundaries by stereo interfacial particle image velocimetry

    International Nuclear Information System (INIS)

    Nguyen, Thien Duy; Wells, John Craig; Nguyen, Chuong Vinh

    2010-01-01

    In investigations of laminar or turbulent flows, wall shear is often important. Nevertheless, conventional particle image velocimetry (PIV) is difficult in near-wall regions. A near-wall measurement technique, named interfacial PIV (IPIV) [Nguyen, C., Nguyen, T., Wells, J., Nakayama, A., 2008. Proposals for PIV of near-wall flow over curved boundaries. In: Proceedings of 14th International Symposium on Applications of Laser Technique to Fluid Mechanics], handles curved boundaries by means of conformal transformation, directly measures the wall gradient, and yields the near-wall tangential velocity profile at one-pixel resolution. In this paper, we show the feasibility of extending IPIV to measure wall gradients by stereo reconstruction. First, we perform a test on synthetic images generated from a direct numerical simulation (DNS) snapshot of turbulent flow over sinusoidal bed. Comparative assessment of wall gradients derived by IPIV, stereo-IPIV and particle image distortion (PID) [Huang, H.T., Fiedler, H.E., Wang, J.J., 1993. Limitation and improvement of PIV. Experiments in Fluids 15(4), 263-273] is evaluated with DNS data. Also, the sensitivity of IPIV and stereo-IPIV results to the uncertainty of identified wall position is examined. As a practical application of IPIV and stereo-IPIV to experimental images, results from turbulent open channel flow over a backward-facing step are discussed in detail.

  2. Mean Characteristics of Conical Vortices Above Roof Eaves of Low–Rise Cubic Buildings Using Particle Image Velocimetry

    Directory of Open Access Journals (Sweden)

    M. Gamboa–Marrufo

    2009-04-01

    Full Text Available Fluctuating low pressures near the edges of flat roofs are often caused when the wind impinges on one corner of the building so that conical vortices form above the diagonal roof edges. In turbulent flow, these vortices vary in position and strength and the underlying surface pressures fluctuate accordingly. A preliminary approach to the study of the mechanism linking instantaneous roof edge pressures with the wind vortical structures involves the evaluation of mean characteristics and positions of the latter. However the flow examination has so far been severely limited by the restriction of available anemometers to single–point sampling. In this experimental study, a 200mm cube has been used to model a building with a flat square roof set at an angle of 45° to the oncoming flow direction, and a Particle Image Velocimetry system was used to capture instantaneous two–dimensional velocity vector images of entire flow cross–sections, both normal to the vortex axis and in planes parallel to that axis. The se vector maps were used to estimate the mean characteristics of the vortices and appropriate observation–plane directions to measure wind velocities in the study of the instantaneous problem.

  3. Multiple Δt strategy for particle image velocimetry (PIV) error correction, applied to a hot propulsive jet

    Science.gov (United States)

    Nogueira, J.; Lecuona, A.; Nauri, S.; Legrand, M.; Rodríguez, P. A.

    2009-07-01

    PIV (particle image velocimetry) is a measurement technique with growing application to the study of complex flows with relevance to industry. This work is focused on the assessment of some significant PIV measurement errors. In particular, procedures are proposed for estimating, and sometimes correcting, errors coming from the sensor geometry and performance, namely peak-locking and contemporary CCD camera read-out errors. Although the procedures are of general application to PIV, they are applied to a particular real case, giving an example of the methodology steps and the improvement in results that can be obtained. This real case corresponds to an ensemble of hot high-speed coaxial jets, representative of the civil transport aircraft propulsion system using turbofan engines. Errors of ~0.1 pixels displacements have been assessed. This means 10% of the measured magnitude at many points. These results allow the uncertainty interval associated with the measurement to be provided and, under some circumstances, the correction of some of the bias components of the errors. The detection of conditions where the peak-locking error has a period of 2 pixels instead of the classical 1 pixel has been made possible using these procedures. In addition to the increased worth of the measurement, the uncertainty assessment is of interest for the validation of CFD codes.

  4. Investigation of the shape change of bio-flocs and its influence on mass transport using particle image velocimetry.

    Science.gov (United States)

    Ren, T T; Xiao, F; Sun, W J; Sun, F Y; Lam, K M; Li, X Y

    2014-01-01

    In this laboratory study, an advanced flow visualization technique - particle image velocimetry (PIV) - was employed to investigate the change of shape of activated sludge flocs in water and its influence on the material transport characteristics of the flocs. The continuous shape change of the bio-flocs that occurred within a very short period of time could be captured by the PIV system. The results demonstrate that the fluid turbulence caused the shift of parts of a floc from one side to the other in less than 200 ms. During the continuous shape change, the liquid within the floc was forced out of the floc, which was then refilled with the liquid from the surrounding flow. For the bio-flocs saturated with a tracer dye, it was shown that the dye could be released from the flocs at a faster rate when the flocs were swayed around in water. The experimental results indicate that frequent shape change of bio-flocs facilitates the exchange of fluid and materials between the floc interior and the surrounding water. This mass transfer mechanism can be more important than molecular diffusion and internal permeation to the function and behavior of particle aggregates, including bio-flocs, in natural waters and treatment systems.

  5. Full report of laser doppler velocimetry (Het-V) data, results , and analysis for pRad shot 0632

    Energy Technology Data Exchange (ETDEWEB)

    Tupa, Dale [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tainter, Amy Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-21

    This was a collaborative shot with AWE investigators Paul Willis-Patel, David Bell, Seth Grant, David Tarr, and James Richley. The shot was assembled in Los Alamos, after which David Bell set up the probe holder and finalized the alignment. The probe holder location and configuration was modified from previous years to make room for the laser illuminated visible imaging diagnostic. The LANL pRad PDV team was Dale Tupa, Amy Tainter, and Patrick Medina. This shot had three PDV probes: one aimed at the center, one aimed at a feature, one aimed at the reverse side of the shot. The shot also had 9 points of a spectroscopy diagnostic. The pRad team helped set up and field the spectroscopy, but did not help with any data analysis. (The support documentation for the PDV results includes a timing map for the spectroscopy.) Please direct questions on the velocimetry to Dale Tupa or Amy Tainter. The shot radiographs were classified, but the data from the optical diagnostics are not.

  6. Pianificazione urbana e comportamenti di viaggio: più di una relazione

    Directory of Open Access Journals (Sweden)

    Elisabetta Vitale Brovarone

    2010-04-01

    Full Text Available L’influenza dei caratteri urbani sulla domanda di mobilità è un tema ampiamente dibattuto e studiato. Al di là delle assunzioni teoriche a riguardo, molti studiosi hanno tentato di individuare empiricamente nessi attestanti questo fenomeno. Gran parte della letteratura scientifica sul tema può essere ricondotta al dibattito sulla città compatta e sullo sprawl. Due principali obiettivi contraddistinguono questo dibattito: la comprensione delle complesse dinamiche che legano la domanda di mobilità ai caratteri urbani e l’individuazione di configurazioni sostenibili degli usi del suolo. Il fenomeno è dunque studiato al fine dello sviluppo di strategie fondate sull’integrazione tra i trasporti e gli usi del suolo, finalizzate a limitare l’uso dell’auto e ad ottenere una distribuzione modale degli spostamenti più equilibrata. Buona parte della ricerca scientifica, specialmente nell’ultimo decennio, è dunque focalizzata sull’identificazione di nessi causali tra gli usi del suolo e i trasporti, per supportare, o in alcuni casi mettere in discussione, esperienze e politiche integrate. Nonostante la quantità e varietà di studi dedicati al tema, il fenomeno è ancora lungi dall’essere compreso e dimostrato empiricamente. Il dibattito in proposito è ampio e l’impressione è che con l’aumentare degli studi in proposito e del livello di approfondimento delle analisi diminuisca la sensazione di chiarezza. Attraverso un’analisi della letteratura, l’articolo mette in evidenza i principali problemi emergenti dal dibattito. Senza negare l’importanza del riconoscimento di nessi causali tra i caratteri degli insediamenti e la domanda di mobilità, opinione di chi scrive è che l’individuazione di questi nessi non debba necessariamente costituire una condizione imprescindibile per la definizione e l’adozione di un approccio integrato.

  7. Linguistica antica e linguistica di oggi

    Directory of Open Access Journals (Sweden)

    Gualtiero Calboli

    2010-11-01

    Full Text Available La linguistica moderna si fonda sulla linguistica antica, in particolare sulla grammatica dei Greci e dei Latini: ad es. il concetto di frase come valore di verità (come la combinazione di parti del discorso sufficiente ad esprimere un giudizio di vero o di falso, che costituisca poi il punto di riferimento di tutti i componenti del discorso (Chomsky e Montagne, è già di Aristotele e poi degli Stoici che hanno sviluppato la dottrina dell’axioma. Partendo, poi, dal criterio della ‘grammaticalizzazione’, largamente usato nella linguistica odierna in una prospettiva di storia della lingua, si affronta il concetto di lingua L o ‘lingua logica’ come attenzione metalinguistica e applicazione della linguistica derivata dal valore di verità (Montagne e Creswell. Si è messo, quindi, in rapporto questo atteggiamento con la tradizione legislativa e giudiziaria mesopotamica, semitica, indo-europea (Ittiti, Greci e Latini. In questo ambito si mostra come da una parte abbia cominciato a formarsi una coscienza linguistica e metalinguistica, e, d’altra parte, come la stessa lingua si sia arricchita di forme più complesse quali congiuntivo e ottativo e altre forme ‘oblique’ nominali e verbali (Vedico, Greco, Latino, Tocario. Lo sviluppo delle lingue indeuropee ha comportato, poi, in alcune lingue un riequilibrio tra forme nominali, pronominali e verbali in stretto rapporto con la struttura della lingua (nascita dell’articolo in Greco e nelle lingue Romanze derivate dal Latino e forte riduzione o scomparsa delle forme nominali del verbo come costruzioni participiali e infinitive (AcI. Si connette, così, il problema dei cambiamenti che sono entrati stabilmente nella lingua come effetto della loro entrata nella ‘core grammar’ della lingua e, quindi, si affronta il problema di come individuare la ‘core grammar’ di una lingua: in Latino individuazione della ‘core grammar’ tramite il bilinguismo (Greco–Latino. In conclusione e in

  8. EFISIENSI PERBANKAN SYARIAH DI INDONESIA

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    Afif Amirillah

    2014-09-01

    Full Text Available This research aims to find out the factors that can cause the efficiency value difference of Islamic Banking in In-donesia. The data at this research is monetary data of Islamic Banking. It was obtained from Bank of Indonesia. Then, it was divided into input and output variables. The determination of input output variables at this research uses Value Added Approach. Its input output variables consist of Demand Deposits, Saving Deposits, Time Depo-sits, Paid -In Capital, Placement at Bank ofIndonesia, Inter Bank Assets, Mudharabah, Musyara kah, Murabahah, Istishna, Ijarahand Qardh. This research used Data Envelopment Analysis method. This method has a strength that is having the capability to measure inefficiency input output variables, so that, the variable can have the efficiency. This research has resulted Islamic Banking efficiency in Indonesia, but it does not include BPRS. The mean efficiency of Islamic banking in Indonesia is 99,94%. Penelitian ini bertujuan mencari faktor –faktor penyebab perbedaan nilai efisiensiperbankan syariah di Indo-nesia yang dibandingkan secara relatif untuk setiap periode. Data yang digunakan pada penelitian ini menggu-nakan data keuangan perbankan syariah yang diperoleh dari Bank Indonesia kemudian dibagi menjadi variabel input dan output. Penentuan variabel input dan output pada penelitian ini menggunakan pendekatan Value Added Approach. Variabel input outputnyaterdiri dari : Giro iB, Tabungan iB, Deposito iB, Modal disetor, Pen-empatan padaBank Indonesia, Penempatan pada bank lain, Mudharabah, Musyarakah, Murabahah,Istishna, Ijarah dan Qardh. Pada penelitian ini menggunakan metode Data Envelopment Analysis yang mempunyai kel-ebihan dalam menghitung efisiensi untuk setiap variabel input outputyang mengalami inefisiensi. Penelitian ini menghasilkan nilai efisiensi perbankan syariah di Indoenesia (tidak termasuk BPRS. Efisiensi perbankan syariah di Indonesia mengalami efisiensi rata-rata sebesar 99,94%.

  9. PERGUMULAN KEBERAGAMAAN DI DUNIA BARAT

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    M Baharudin

    2016-03-01

    Full Text Available Abstract: This paper aims to find the answer to a fundamental question: what is religion? How is the phenomenon of religionin the western world? And how religious the Western world in this contemporary Era? In the discussion note several things, among others: 1. Religionisa systemof beliefs and practicesof life according to these beliefs. Religionis the rules on how to live a physically and mentally. Religionisa reference of life in its various aspects, including aspects of common life or social life. 2. In medieval times, religionis seenas having an absolute and universal truth concretely been visualizedin the Western world. 3. In the post modernera of modernity and religion is criticize dan dindistortion, the era of religion merely a matter of discussion and separated with practical life, religionis also considered to hinder the progression of man. Abstrak: Tulisan ini bertujuan menemukan jawaban mendasar atas pertanyaan: apa itu agama? Bagaimana fenomena agama di dunia Barat? Dan bagaimana keberagamaan dunia Barat pada Era kontemporel ini? Dalam pembahasan diketahui beberapa hal antara lain: 1. Agama ialah sistem kepercayaan dan praktek hidup yang sesuai dengan kepercayaan tersebut. Agama ialah peraturan tentang cara hidup lahir batin. Agama adalah acuan hidup berbagai aspeknya, termasuk aspek kehidupan bersama atau kehidupan sosial. 2. Pada abad pertengahan, agama dipandang sebagai yang memiliki kebenaran mutlak dan universal yang secara kongkrit pernah divisualisasikan di dunia Barat. 3. Pada era modernitas dan post¬modern agama dikritik dan di distorsi, pada zaman tersebut agama sekedar menjadi bahan diskusi dan dipisahkan dengan kehidupan praktis, agama juga dianggap menghalangi progresivitas manusia. Keywords: Pergumulan, Keberagamaan, Dunia Barat

  10. Reformasi di Kementerian Pertahanan RI

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    Beni Sukadis

    2016-11-01

    Full Text Available Abstrak Reformasi bidang pertahanan yang dialami Indonesia sejak disahkan UU Pertahanan Negara dan UU TNI hingga kini belum selesai karena beberapa faktor yang cukup menghambat reformasi ini. Beberapa faktor yang menghambat, yaitu masih ada budaya paternalistik dalam birokrasi, masih ada ketidakjelasan kedudukan antara menteri pertahanan dan panglima TNI dalam pembagian wewenang khususnya terkait hubungan sipil-militer dan kepemimpinan sipil yang lemah dalam mengelola reformasi di Kementerian Pertahanan. Hingga saat ini implementasi supremasi sipil masih samar di Kementerian Pertahanan, walaupun secara faktual menteri pertahanan berasal dari sipil, tapi di sisi lain dominasi militer dalam jabatan pengambilan keputusan masih terjadi. Padahal supremasi sipil seharusnya direpresentasikan dalam wujud nyata bukan hanya dari hanya dari satu posisi pimpinan, yakni bagaimana otoritas sipil secara dominan dapat mengambil keputusan politik yang otonom sesuai dengan kebijakan negara yang dimandatkan oleh UU dan aturan yang ada. Kata kunci: reformasi pertahanan, hubungan sipil militer, supremasi sipil.   Defense reform still underway since Indonesia passed the Law on State Defense and the TNI the reform law has not completed yet, because there are many factors that impede the reform process. Some of the factors are the paternalistic culture still exist in the bureaucracy, there is also ambiguity on the relations between the Defense Minister and the Commander of TNI in the division of labor especially to civil-military relations and weak civilian leadership in managing the reform at the Ministry of Defense. Until now, the implementation of civil supremacy within the Ministry is vague, although the ministers are civilian, but in fact the military domination in decision making process remains strong. Whereas, civil supremacy should not be exemplified on the top position, but the civilians authority take the lead in the decision making in accordance to the

  11. Penerapan Falsafah Deming di Perpustakaan

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    Anindya Gita P

    2018-02-01

    Full Text Available Abstract Today, the awareness of the importance of developing quality not only in business, but also penetrated in the field of non-profit as a library. Libraries in Indonesia are starting to realize the importance to promote the quality. Proven by the implementation of quality management systems in several libraries in Indonesia, for example, with ISO 9001: 2008 as well as the application of Total Quality Management from Japan. One influential figure in this field is W. Edwards Deming, an American statistician and management consultant. Deming had transformed Japan from the downturn as a result of the second world war into the advanced industrial countries. Deming's famous philosophy of quality that is 14 points the key to successful management. Although the philosophy of quality management is made in the fields of industry, but this theory can be applied also in the field of non-profit as a library. Deming theory concepts can help an organization's library to determine the appropriate steps in achieving quality services.   Keyword : Quality Management, Library Management, Management Figures   Abstrak Saat ini kesadaran akan nilai penting mutu berkembang tidak hanya pada bidang bisnis tetapi juga merambah dalam bidang non profit seperti perpustakaan. Perpustakaan di Indonesia mulai menyadari pentingnya untuk mengedepankan mutu. Terbukti dengan adanya penerapan sistem manajemen mutu di beberapa perpustakaan di Indonesia, contohnya dengan ISO 9001:2008 maupun penerapan Total Quality Manajemen yang berasal dari Jepang. Salah satu tokoh yang berpengaruh dalam bidang ini yaitu W. Edwards Deming, seorang ahli statistik Amerika dan konsultan manajemen. Deming telah berhasil merubah kondisi Jepang yang terpuruk akibat dari perang dunia kedua menjadi negara industri yang maju. Falsafah mutu Deming yang terkenal yaitu 14 poin kunci sukses manajemen. Walaupun falsafah manajemen mutu ini dibuat dalam bidang industri, namun teori ini bisa diterapkan juga

  12. Un modello e-learning di training per i test d'ingresso alla facoltà di scienze

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    Manuela Moscucci

    2011-12-01

    Full Text Available Applicazione di un modello di interazione didattica in modalità e-learning, realizzato in una classe virtuale e finalizzato al superamento del test di ammissione all’Università.

  13. LE OSSIDIANE DI PALMAROLA I MARKER DI PROVENIENZA

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    Andrea Macchia

    2012-04-01

    Full Text Available

    Le tracce di ossidiane e la caratterizzazione delle componenti chimiche presenti nei luoghi oggetto di indagini archeologiche, permettono l'individuazione delle antiche rotte commerciali. In Italia le aree individuate sono Monte Arci in Sardegna, Lipari e Pantelleria in Sicilia e Palmarola nel Lazio.

     

    Obsidian  from  Palmarola:  source  markers

    A  chemical  characterization  of  the  main  components  and  traces  of  obsidian  allows identifi cation  of  commercial  routes  in  antiquity.  Obsidian  sources in Prehistoric Italy were mainly four: Monte Arci in Sardinia, the islands of Lipari and Pantelleria in Sicily and the island of Palmarola in Lazio. A survey methodology on samples of obsidian from several Neolithic sites in Lazio has been developed, comparing three different analytical techniques: SEM-EDS, XRF and LA-ICP-MS, in order to obtain a wider range of data to be compared with literature records and processed by Principal Component Analysis (PCA, to defi ne relationships between samples and to assign each finding its origin.

  14. H-Star di Trimble Un sistema GPS in doppia frequenza per rilievi di alta precisione

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    Redazione Redazione

    2005-10-01

    Full Text Available L’acquisizione dati con H-Star è gestita con un software specificatamente ideato per i dati di elevata accuratezza. Esso, dotato di indicatore Predicted PostprocessedAccuracy (PPA, mostra chiaramente la precisione che si otterrà una volta che i dati H-Star verranno postprocessati. L’elaborazione di questi dati è studiata appositamente per raggiungere una precisione superiore ai 30 cm con non più di due minuti di dati continui.

  15. Il Servizio Intercultura dell’Istituto di Terapia Familiare di Firenze

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    Giancarlo Francini

    2013-12-01

    Full Text Available Nel corso del presente articolo vengono descritte le premesse epistemologiche e le metodologie adottate dagli operatori del Servizio Intercultura dell’Istituto di Terapia Familiare di Firenze (ITFF nel lavoro con la popolazione migrante ed elencati gli interventi fatti nel territorio. Il Servizio Intercultura dell’ITFF si è interrogato in questi anni sul valore della cultura come porta d’ingresso nel rapporto con il migrante; nel chiedere loro di narrare aspetti della loro cultura condividiamo aspetti della nostra cultura. L’incontro con il malinteso, che come dice Jankelevitch «(… è un quasi niente» (Jankelevitch, 1987, p. 233, perché se fosse stato qualcosa di più ce ne saremmo accorti e se fosse qualcosa di meno non sarebbe significativo, ci permette di aprirci a un rapporto che cambia entrambi, operatore e migrante, nella relazione. È nella relazione e attraverso il racconto dell’evento migrazione e del ciclo di vita che si costruisce e si cerca un linguaggio comune per la descrizione e l’espressione del disagio. Il lavoro con i migranti deve fare i conti con le difficoltà legate all’impiego, alla casa, al permesso di soggiorno e non ultimo alla brevità di alcuni incontri, perché per alcuni la nostra città è solo una tappa di un percorso che continua alla ricerca di una sistemazione migliore. Nel territorio di Firenze sono stati messi a punto una serie di servizi: oltre alla clinica e a uno sportello di consulenza, ci si dedica alla formazione degli operatori che lavorano con i migranti. Esempi di queste attività sono: un progetto di peer tutoring in alcune scuole superiori, uno di formazione per le assistenti sociali al fine di proporre un protocollo più efficace di presa in carico dei migranti, una serie di focus group con dipendenti Asl all’interno del progetto “Mamma segreta” della regione Toscana; inoltre, la collaborazione con le associazioni presenti sul territorio ha permesso un contatto

  16. Il concetto di storia della lingua nell'opera grammaticale di Benedetto Buommattei

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    Gunver Skytte

    1991-12-01

    Full Text Available Che la storia della lingua sia una disciplina linguistica di data recente, fondata nell'800, soprattutto grazie alle ricerche pionieristiche di insigni filologi tedeschi, è un'opinione comunemente accettata, ed essa è probabilmente anche giustificata attraverso la classificazione datane di disciplina. A questo dato di fatto si deve senz'altro l'opinione altrettanto estesa che prima dell'800 non esistesse il concetto di linguistica diacronica o cambiamento linguistico in senso scientifico, come pure quella non meno erronea che la linguistica, come scienza, sia stata fondata solo nell'800.

  17. D. Felini (a cura di, Video game education. Studi e percorsi di formazione

    Directory of Open Access Journals (Sweden)

    Alex Tribelli

    2013-03-01

    Full Text Available Nei confronti di una trattazione scientifica dei videogame c’è tuttora qualche scetticismo. I pregiudizi, più volte denunciati, ancora hanno qualche sussistenza: persiste qualche analisi sociale che considera i videogame oggetti diabolici che provocano isolamento e comportamenti violenti nei teenager. Pur constatando una progressiva inversione di tendenza, Video game education. Studi e percorsi di formazione, curato da Damiano Felini, si propone di sgretolare la concezione che la società contemporanea ha dei videogame, dimostrando come questi oggetti mediali possono addirittura divenire uno strumento di formazione e crescita delle persone.

  18. Inchiesta sulle condizioni di vita e sanitarie degli immigrati presenti nella cittá di Messina

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    D. Alfino

    2003-05-01

    Full Text Available A Messina e nella sua provincia vivono circa 7328 stranieri con regolare permesso di soggiorno (dati aggiornati al 31/12/02 Questura di Messina Ufficio Immigrati ai quali si deve aggiungere una quota di soggetti, irregolari e clandestini, stimata intorno al 25% dei regolari (fonte dati Caritas, Kirone. Le Comunità maggiormente presenti sono quelle provenienti dalle Filippine, Marocco, Sri Lanka. Al fine di valutare il livello di assistenza sanitaria fornita agli immigrati, nel periodo compreso tra Dicembre 2002 e Maggio 2003, abbiamo intervistato un campione di immigrati relativamente alle loro abitudini di vita, sul tipo di lavoro svolto, sullo stato di salute attuale e pregresso, sull’eventuale ricorso alle strutture del Servizio Sanitario Locale e sulle vaccinazioni praticate nel Paese di origine e in Italia. Sono stati intervistati 1204 soggetti (42,19% Sri Lanka, 24,75% Marocco, 25,91% Filippine, 3,15% Tunisia, 1,82% Senegal, 0,16% Algeria. La comunità cinese, anch’essa significativamente presente nella città, si è dimostrata diffidente e non interessata alla nostra indagine. Sono state evidenziate notevoli carenze del Servizio Sanitario locale, per mancanza di un sistema di monitoraggio e prevenzione rivolto agli immigrati. Il 99% degli intervistati pur essendo iscritto al S.S.N.ed avendo nell’84% il medico di famiglia, non possiede il libretto sanitario, è stato sottoposto alle vaccinazioni obbligatorie del Paese di origine, ma non le ha integrate con quelle Italiane, ad eccezione del 2,3% di soggetti che ha praticato quella antiinfluenzale e dell’ 1,2% che si è sottoposto a quella antitifica ed antiepatite A per motivi occupazionali. Malgrado l’intervista mirasse a sondare il livello di assistenza sanitaria, ha svelato altri dettagli: il 79,2% dei soggetti cerca di mantenere le abitudini alimentari originarie; solo lo 0,5% ha dichiarato di aver subito un infortunio, mentre riguardo al tipo di attività svolta si rilevano

  19. Il monastero di Bobbio in età altomedievale

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    Eleonora Destefanis

    2003-11-01

    Full Text Available Il monastero di Bobbio, sorto sull’Appennino piacentino per iniziativa di S. Colombano e con il sostegno del re longobardo Agilulfo, ha conosciuto una lunga storia di studi che ne hanno messo di volta in volta in luce l’importanza come centro scrittorio e di raccolta di testi, il ruolo di primo piano quale interlocutore delle monarchie avvicendatesi nel corso dell’altomedioevo, la posizione di spicco nell’esperienza del monachesimo insulare sul Continente, riflessa da una cospicua produzione ...

  20. Psicoanalisi ed educazione: il lavoro di Vera Schmidt e di Sabina Spielrein nell’asilo sperimentale di Mosca (1921-1925

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    Merete Amann Gainotti

    2012-12-01

    Full Text Available Negli anni 1921-1923 a Mosca, sulla scia delle profonde trasformazioni politiche e sociali innescate dalla Rivoluzione di ottobre si colloca un esperimento educativo originale, promosso da Vera Schmidt, una pedagogista formata alle idee psicoanalitiche, che si proponeva di cercare nuove vie educative per la prima infanzia sulla base delle recenti conquiste e conoscenze fornite dalla teoria psicoanalitica di S. Freud. Obiettivo di questo contributo è di fornire un breve excursus storico relativo alla diffusione della psicoanalisi in Unione sovietica e alla fondazione dell'asilo sperimentale di Mosca, di ricordare le figure delle due studiose Vera Schmidt e Sabina Spielrein che hanno animato l'iniziativa, il cui lavoro scientifico è rimasto in ombra rispetto a quello dei loro più famosi colleghi S. Freud e di C.G. Jung; infine si intende rendere conto dei principi educativi che esse cercarono di mettere in pratica nell'asilo sperimentale di Mosca.

  1. Castelli di carta. La piega per la costruzione di superfici articolate

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    Andrea Casale

    2012-06-01

    Full Text Available L’antica arte del piegare la carta, l’Origami, sta vivendo un rinnovato interesse che coinvolge molti aspetti della ricerca.  Con il termine origami, si intende lo studio del modo di piegare il foglio di carta per imporgli una specifica forma.  La superficie tassellata per mezzo di specifiche pieghe, si propone come un nuovo soggetto di studio: la superficie piegata articolata. La forma congiunta al movimento, assume un particolare interesse nella contemporanea ricerca geometrica e architettonica. Il panorama contemporaneo, propone opere di architettura “responsiva”, capaci di modificare le proprie caratteristiche per adeguarsi a nuove condizioni. La superficie piegata articolata sembra particolarmente adatta a descrivere questo modo d’intendere l’architettura, reagendo a diverse volontà e di conseguenza modificando la propria conformazione attraverso un attento controllo progettuale della forma.

  2. Domotica e disabilità negli ambienti di apprendimento. Esiti di un progetto

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    Tamara Zappaterra

    2013-11-01

    Full Text Available In un lavoro sinergico ed interdisciplinare tra ricercatori dell’area pedagogica, dell’area ingegneristica e di quella medica, si è testata la possibilità di adattamento di dispositivi domotici all’ambiente scolastico, ambito non ancora esplorato dalla domotica, ed è stato progettato e realizzato un prototipo di dispositivo innovativo ed originale modellato sulle peculiarità dell’utente nel contesto scolastico. Per quanto riguarda i risultati raggiunti,sono state realizzate tre stazioni domotiche composte da un banco touch-screen collegato ad una LIM. Lo strumento si sta rivelando in grado di facilitare e motivare ad imparare, di trasmettere apprendimenti, di migliorare la qualità della vita del gruppo classe.

  3. Enrico Fermi significato di una scoperta

    CERN Document Server

    2001-01-01

    Questo volume è la riedizione, rinnovata ed ampliata, del volume "Enrico Fermi. Significato di una scoperta" edito dal FIEN (Forum Italiano dell'Energia Nucleare) nel 1982 e nel 1992 in occasione, rispettivamente, del 40mo e del 50mo anniversario della pila di Fermi.

  4. I LABIRINTI NARRATIVI DI MARCELLA CIONI

    African Journals Online (AJOL)

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    La critica ufficiale non ha ancora colto l'alta cifra stilistica e la complessa struttura .... Il viaggio all'interno di se stessi, conseguente al trauma conflittuale col mondo ..... proprio “centro”, che si scatena in una forte energia pulsionale. (nel caso di ...

  5. La mafia ai tempi di Expo

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    Il Comitato di esperti antimafia del Comune di Milano

    2016-11-01

    Full Text Available La sezione “Il documento” propone due capitoli della Relazione conclusiva redatta dal “Comitato di esperti per lo studio e la promozione di attività finalizzate al contrasto dei fenomeni di stampo mafioso e della criminalità organizzata sul territorio milanese, anche in vista della manifestazione Expo Milano 2015”, consegnata il 28 ottobre 2016 all’ex Sindaco di Milano Giuliano Pisapia e all’attuale Sindaco Giuseppe Sala. Gli estratti qui proposti riguardano le infiltrazioni mafiose in Expo e la presenza mafiosa a Milano.  Parole chiave: Comitato di esperti; Expo 2015; Milano; ‘ndrangheta; appalti The section ‘The Document” offers two chapters of the last report issued by the Antimafia Committee of the City Council of Milan (Comitato di esperti per lo studio e la promozione di attività finalizzate al contrasto dei fenomeni di stampo mafioso e della criminalità organizzata sul territorio milanese, anche in vista della manifestazione Expo Milano 2015, and presented on the 28th October 2016 to the former Mayor of Milan, Giuliano Pisapia, and to the actual Mayor Giuseppe Sala.  The excerpts here proposed regard the problems faced by the Committee in the years which have led up to Expo 2015 and the new scenarios of the presence of the Mafia in the area of Milan.  Keywords: Committee of experts; Expo 2015; Milan; ‘ndrangheta; public procurements

  6. Stelle, galassie e universo Fondamenti di astrofisica

    CERN Document Server

    Ferrari, Attilio

    2011-01-01

    Scopo del testo e' introdurre i concetti base della fisica stellare, della fisica delle galassie e della cosmologia con approccio essenzialmente fisico. La prima parte presenta le tecniche osservative sia nella banda ottica, sia nelle alte frequenze e nella banda radio. La parte dedicata alle stelle discute modelli di struttura e l’evoluzione. La terza parte e’ dedicata alle galassie, morfologia, formazione ed evoluzione, per giungere allo studio della distribuzione sulle grandi scale. La sezione di cosmologia presenta i modelli cosmologici relativistici, con la discussione del big-bang, inflazione, materia oscura, energia oscura. Il testo rappresenta la raccolta delle lezioni tenute dall’autore per i corsi introduttivi di astrofisica delle lauree specialistiche in Fisica e Astrofisica nei passati 30 anni, ma include elementi avanzati utili per corsi introduttivi di astrofisica nel dottorato in Fisica. Il testo e' anche stato utilizzato in forma preliminare da colleghi di altre sedi.

  7. Il tempo perturbante di uno sguardo

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    Piero Zanini

    2010-06-01

    Full Text Available Nell’autunno del 1973 Pier Paolo Pasolini viene invitato a partecipare ad una rubrica televisiva intitolata Io e …, nella quale intellettuali, poeti, registi, musicisti, scrittori sono chiamati a scegliere e a parlare di un’opera d’arte a cui tengono in modo particolare. Dopo un crescendo di ripensamenti intorno al tema da trattare (una pietra, un muretto, una fontana Pasolini sceglie infine di concentrare la sua attenzione sulla forma della città, a partire da due luoghi tanto a lui familiari quanto tra loro radicalmente diversi: la medievale Orte, la fascista Sabaudia. Il risultato della sua partecipazione alla trasmissione è una sorta di ‘scritto corsaro’ per immagini, Pasolini e… la forma della città1, un documento importante e complesso per comprendere la “sostanza di Pasolini” [Contini, 1988] in quel momento particolare della sua vita che sono i primi anni Settanta.

  8. RADIKALISME DI INDONESIA: Antara Historisitas dan Antropisitas

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    Ahmad Asrori

    2017-02-01

    Full Text Available Studi ini mencoba menganalisis faktor-faktor yang mendorong munculnya radikalisme di Indonesia. Berdasarkan hasil penelitian ditemukan sekurang-kurangnya ada 3 faktor, yakni pertama, perkembangan di tingkat global, Kedua, penyebaran paham Wahabisme dan yang ketiga adalah kemiskinan. Situasi yang kacau di negara-negara Timur Tengah khususnya di Afghanistan, Palestina, Irak, Yaman, Mesir, Syiria, dan Turki, dipandang oleh kelompok-radikal sebagai akibat dari campur tangan Amerika, Israel, dan sekutunya. Pada saat yang sama, Masuknya faham Wahabisme yang mengagungkan budaya Islam ala Arab yang konservatif ke Indonesia telah ikut mendorong timbulnya kelompok eksklusif yang sering menuduh orang lain yang berada di luar kelompok mereka sebagai musuh, kafir dan boleh diperangi. Faktor ketiga adalah kemiskinan. Meski faktor ini tidak secara langsung berpengaruh terhadap merebaknya aksi radikalisme, namun perasaan sebagai elemen masyarakat yang termarjinalkan dapat menjadi faktor pendorong bagi seseorang untuk terjebak dalam proganda radikalisme.

  9. Waveform Diversity and Design for Interoperating Radar Systems

    Science.gov (United States)

    2013-01-01

    University Di Pisa Department Di Ingegneria Dell Informazione Elettronica, Informatica , Telecomunicazioni Via Girolamo Caruso 16 Pisa, Italy 56122...NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) University Di Pisa Department Di Ingegneria Dell Informazione Elettronica, Informatica ...DIPARTIMENTO DI INGEGNERIA DELL’INFORMAZIONE ELETTRONICA, INFORMATICA , TELECOMUNICAZIONI WAVEFORM DIVERSITY AND DESIGN FOR INTEROPERATING

  10. Fourth International Congress on Industrial and Applied Mathematics. Book of Abstracts

    Science.gov (United States)

    1999-01-01

    Dipartimento di Matematica , Universita’ di Pavia, Italy) Logarithmic Sobolev inequalities for kinetic semiconductor equations In this paper we analyze the...terms of Whitney forms. FERNANDES, Paolo (Istituto per la Matematica Applicata del Consiglio Nazionale delle Ricerche, Italy) Dealing with realistic... Matematica dell Universita di Pavia, Italy. PERUGIA, Ilaria (Diaprtimento di Matematica , Universita’ di Pavia - Italy) An adaptive field-based method

  11. A Simple Algorithm for Obtaining Nearly Optimal Quadrature Rules for NURBS-based Isogeometric Analysis

    Science.gov (United States)

    2012-01-05

    Università degli Studi di Pavia bIstituto di Matematica Applicata e Tecnologie Informatiche “E. Magenes” del CNR, Pavia cDAEIMI, Università degli Studi di...Cassino d Institute for Computational Engineering and Sciences, University of Texas at Austin eDipartimento di Matematica , Università degli Studi di

  12. Introduzione al laboratorio di fisica misure e teoria delle incertezze

    CERN Document Server

    Ciullo, Giuseppe

    2014-01-01

    Frutto dell'esperienza decennale come supporto per la didattica di laboratori di fisica sia a livello di corsi triennali che di corsi di laurea magistrale, il libro si è concretizzato nella "responsabilità" di tali corsi di laboratorio per fornire un opera di utilizzo dei vari strumenti, che un approccio sperimentale alla fisica richiede. Si parte dalla descrizione delle problematiche delle incertezze in modo operativo e si introducono i concetti fondamentali per l'analisi dei dati e la misura. Invece di una serie dispersiva di testi, con approcci, convenzioni e simbolismi differenti, poco fruibili per l'applicazione diretta ad un laboratorio dei primi anni, il libro fornisce le indicazioni utili per affrontare lo studio dei fenomeni fisici in modo immediato, fornendo anche indicazioni rigorose e giustificazioni teoriche. Lo stimolo teorico-pratico, che uno sperimentale-scienziato deve percepire, non esula dal comprendere problematiche di maggiore approfondimento. L'opera rende fruibili concetti e strumenti...

  13. Jalan Terjal Kebijakan Desentralisasi di Indonesia di Era Reformasi

    Directory of Open Access Journals (Sweden)

    Mudiyati Rahmatunnisa

    2015-12-01

    Full Text Available Abstrak Indonesia memasuki era baru sejak berakhirnya rezim Orde Baru pada pertengahan tahun 1998. Salah satu aspek yang mengalami perubahan adalah hubungan antara pemerintah pusat dan daerah. Momentum tersebut dimulai dengan diluncurkannya Paket Undang-Undang Tahun 1999 tentang Pemerintah Daerah yang berimplikasi pada perubahan signifikan hubungan pusat-daerah, sehingga kabupaten/kota memperoleh limpahan hampir semua urusan pemerintahan yang sebelumnya berada di tangan pusat atau provinsi. Secara normatif, perubahan ini dipandang radikal dan revolusioner sehingga pemberlakuan Paket Undang-Undang Tahun 1999 tentang Pemerintahan Daerah ini dianggap sebagai awal perubahan sistem pemerintahan yang sentralisk ke desentralisk. Saat ini, proses reformasi yang telah bergulir lebih dari satu dekade ternyata menunjukkan kebijakan desentralisasi di Indonesia dibuat dan dilaksanakan dengan tidak terbebas dari pengaruh politik. Kontroversi dan proses revisi serta lahirnya berbagai peraturan yang berimplikasi pada pasang surut derajat otonomi yang dimiliki daerah, merupakan salah satu indikator kuatnya pengaruh politik terhadap keberadaan kebijakan desentralisasi di Indonesia. Tulisan ini berupaya untuk membahas secara kritis permasalahan yang muncul dari kelahiran Undang-Undang Nomor 23 Tahun 2014 tentang Pemerintahan Daerah terkait perubahan normatif dalam undang-undang, dampak terhadap tatanan pemerintahan daerah, serta potensi untuk membuat proses-proses politik dan pemerintahan daerah menjadi lebih otonom. Abstract Indonesia has entered a new era since the collapse of the New Order in the mid-1998. Iniated by the implementaon of Legislaon Package of 1999, relationship between central and regional governments has significantly changed. Per the change, regional governments especially on district/municipality levels are given extensive authority that previously only belonged to either central or provincial governments. Normatively, such change is

  14. Detection system qualification for direct measurement of thyroid internal contamination by radioiodine; Qualificazione di un sistema di rilevazione trasportabile per misure dirette di contaminazione interna di radioiodio

    Energy Technology Data Exchange (ETDEWEB)

    Tiberi, V.; Battisti, P.; Gualdrini, G. [ENEA, Centro Ricerche Ezio Clementel, Bologna (Italy). Dipt. Ambiente

    1999-07-01

    The work deals with a detection system qualification for direct measurements of thyroid internal contamination by radioiodine. The isotopes {sup 131}I and {sup 125}I are the most frequently used in nuclear medicine. Because of their volatility they are very dangerous for thyroid contamination by inhalation. The system has been projected to be easily and fast used and above all transportable where the control is necessary. These characteristic make it able to realise supervision programs of internal contamination by radioiodine. In fact due the very high control frequencies (each 15 days for {sup 131}I), these programs are usually very expensive and demanding when they are executed in external measurement laboratories. The following steps are described: devices presentation, calculation of energy and efficiency parameters, minimum detectable activity, time system reliability, best operative conditions in the measurements. At the end an application example of the system is reported. [Italian] Il presente lavoro consiste nella qualificazione di un sistema di rivelazione per misure dirette di contaminazione interna da radioiodio in tiroide, progettato per essere maneggevole, di semplice e rapido impiego e trasportabile sul luogo dove e' richiesta la misura. Il sistema e' stato studiato per la realizzazione di programmi di sorveglianza della contaminazione interna da radioiodio che, richiedendo frequenze di controllo elevate (quindicinali per lo {sup 131}I), sono estremamente impegnativi ed onerosi, soprattutto se i controlli vengono effettuati in centri di misura esterni. Dopo la determinazione dei parametri della calibrazione in energia ed efficienza, la minima attivita' rivelabile, l'affidabilita' del sistema nel tempo e le condizioni operative ottimali da adottare in sede di misura, viene verificata la piena affidabilita' del sistema in un programma di sorveglianza della contaminazione interna da radioiodio.

  15. Ripensare la Grande Guerra: ancora a proposito di Viva Caporetto! La rivolta dei santi maledetti di Curzio Malaparte.

    Directory of Open Access Journals (Sweden)

    Federico Montanari

    2016-05-01

    Full Text Available La prima guerra mondiale, anche nell’occasione del suo centenario, è stata da sempre oggetto di riflessioni per quanto riguarda la memorialistica, i diari, la letteratura e il cinema. In quanto evento, come più volte sottolineato, di inizio (del “secolo breve” di cesura del tempo della modernità, di disillusione (rinarrata e raccontata per una generazione, e al contempo oggetto di mitizzazione (i fascismi e il mito delle trincee sanguinanti o di rimozione e di opposizione (per un’altra generazione, quella dell’antifascismo e della resistenza. Laboratorio sociale, scientifico e culturale ("L’officina della guerra", per dirla con Gibelli, per il rapporto fra innovazione letteraria, diaristica e percezione (da Céline a Cendrars, a Musil. Lo scopo di questa comunicazione è, tenendo conto di tale vasto orizzonte di esperienze, di riprendere un caso specifico: l’ipotesi del legame guerra/”rivoluzione possibile”, per come presentato da Curzio Malaparte nel suo Viva Caporetto! La rivolta dei santi maledetti. E’ noto il percorso complesso e contraddittori di Malaparte (dall’adesione al fascismo, fino alla sua critica e rifiuto, attraverso la visione anarchica che gli era propria, e all’avvicinarsi al partito comunista e alle idee di sinistra dopo la seconda guerra mondiale. In ogni caso, cercheremo di mostrare quali dispositivi valoriali e discorsivi vengono a costituirsi nel testo di Malaparte. Testo interessante anche per un lavoro di comparazione con altri testi e autori: sia dal punto di vista tematico che di organizzazioni dei punti di vista, nelle forme dell’enunciazione; così come delle organizzazioni narrative, che espongono la vicenda non solo della disfatta di Caporetto, ma, più in generale, del “momento in cui gli uomini decidono di smettere di combattere” e, forse, di trasformare questo momento in qualcos’altro.

  16. Inventare l’altro. Forme di pseudo-traduzione nella scrittura di Salvatore Di Giacomo e Luigi Capuana.

    Directory of Open Access Journals (Sweden)

    Valentina Fulginiti

    2014-05-01

    Full Text Available Being an extreme case of fictitious representation of linguistic otherness, pseudo-translation challenges the idea of a fatal and exclusive link between language and national ethos, a fundamental notion in the Nineteenth-century linguistic and literary culture. The present article compares two emblematic cases of pseudo-translation in post-Unification Italian culture: Luigi Capuana’s hoax Un poeta danese (published in 1882 and the earliest short stories published by Salvatore di Giacomo in 1878, mistakenly considered a plagiarizing translation from an uncredited German original. Their use of pseudo-translation is marked by opposite goals of parody and stylistic imitation; however, both authors challenge the fundamental assumption underlying the notion of «ethnicity of language». Pseudo-translation thus becomes a space of linguistic elaboration, complementary to the author’s direct involvement in translating major European works into Italian (such as Ibsen’s masterpiece A House of Dolls, which Capuana translated in 1891, and Edmond de Goncourt’s novel Sœur Philomèle, which Di Giacomo translated in 1892. Translation thus provides a free space for authors to experiment with new expressive solutions and challenge commonplaces about language and identity: such reflection on the limits of language and nations represent a direct contribution to the linguistic unification of Italy. Caso estremo di rappresentazione fittizia del- l’alterità linguistica, la pseudo-traduzione chiama in causa l’idea del legame unico e “fatale” fra lingua e nazione – concetto fondamentale nella cultura linguistica del XIX secolo. L’articolo mette a confronto due casi emblematici di pseudo-traduzione nella cultura meridionale post-unitaria: la beffa letteraria di Luigi Capuana Un poeta danese (1882 e le ‘tedescherie’ di Salvatore di Giacomo, gruppo di novelle pubblicate nel 1878 che molti considerarono (a torto un plagio da ignoto autore tedesco

  17. Thermal hydraulics-I. 1. Phasic Discrimination in Two-Phase-Flow Measurements Using Particle Image Velocimetry

    International Nuclear Information System (INIS)

    Todd, D.R.; Ortiz-Villafuerte, J.; Schmidl, W.D.; Hassan, Y.A.; Sanchez-Silva, F.

    2001-01-01

    Information about the dispersed phase parameters -such as location, displacement, and interfacial area -are very important in the analysis of two-phase flows. Local flow disturbances in the continuous phase can be quite significant when the dispersed phase (i.e., a particle, drop, or bubble) passes through the medium. Application of point-wise measurement methods such as hot wire anemometry and laser anemometry suffer significant limitations in two-phase-flow measurements when these local disturbances are strong. Also, these two methods typically lack the ability to quantify the dispersed phase. Previous work has shown that meaningful analysis of the instantaneous continuous phase velocity field requires knowledge of the dispersed phase parameters, especially location and trajectory. Continuous phase parameters such as the local instantaneous vorticity and local turbulence fluctuations are influenced by the passage of the dispersed phase. Thus, development of two-phase-flow models (such as a bubble wake model) requires knowledge of the relative location of a local continuous phase parameter to the dispersed flow object (i.e., directly behind or off the side of the object). Also, conditional sampling must be performed using a meaningful parameter as the sampling point, i.e., the passage of a specific size of bubble. A system has been developed at Texas A and M University to quantify the dispersed phase parameters for two-phase bubbly flow in a vertical pipe with co-current upward flow. This system uses an orthogonal shadow particle image velocimetry (SPIV) technique, which instantaneously measures three-dimensional bubble locations, volumes, and interfacial areas -while measuring the three-dimensional bubble velocities and accelerations over a sequence of discrete measurements. The SPIV system is capable of analyzing flows with a large number of bubbles in close proximity. A set of sample images has been collected as part of the preliminary testing and development

  18. Incidenza di meningiti nell'ASL di Brescia nei primi mesi del 2003

    Directory of Open Access Journals (Sweden)

    M. Magoni

    2003-05-01

    Full Text Available

    Obiettivi: nell’ASLdi Brescia durante i mesi di gennaiomaggio 2003 si è verificato un consistente aumento di casi di meningite che ha allarmato oltre agli operatori sanitari anche l’opinione pubblica locale.

    Metodi: i dati riguardanti i casi di meningite verificatisi dal gennaio 1999 al maggio 2003 sono stati raccolti dal Servizio Igiene Pubblica dell’ASLdi Brescia.

    Tenuto conto della omogeneità dei dati nel quadriennio 1999- 2002 e della stagionalità che le meningiti possono avere, sono stati calcolati i tassi di incidenza per i primi cinque mesi dell’anno per tutte le meningiti in generale e per agente eziologico, durante il quadriennio 1999-2002. Tali tassi sono stati confrontati con i tassi corrispondenti nei primi mesi del 2003.

    Risultati: nel primi 5 mesi del 2003 si sono registrati in tutto 48 casi, di cui 9 da meningocco, 13 da pneumococco, 14 virali, 3 da altri agenti batterici e 8 senza agente microbico identificato. Nei 4 anni precedenti erano stati notificati 66 casi di meningite nei primi 5 mesi dell’anno, con una media annua di 16.5. Il tasso di incidenza di meningite in gennaio-maggio è stato quindi il triplo nel 2003 (rischio relativo = 2.9 rispetto ai 4 anni precedenti (p=0.0001. L’eccesso di incidenza si è riscontrato per tutti i tipi di meningite considerati in base all’agente eziologico.

    L’analisi per diverse età ha mostrato un aumento di incidenza sia nei bambini che nei giovani adulti e negli anziani. Non si è riscontrata alcuna differenza statisticamente significativa tra l’incidenza nel comune di Brescia (area urbana rispetto all’intera ASL nel periodo in studio.

    Conclusioni: l’aumento di incidenza per meningiti
    osservato nel 2003 non sembra spiegabile in termini di variabilità casuale del fenomeno da un anno all’altro e riguarda tutti i tipi di meningite e tutte le categorie d

  19. Spazi d’autore. Riscrittura e passaggi di testo ne La strada di Levi

    Directory of Open Access Journals (Sweden)

    Matteo Martelli

    2016-07-01

    Full Text Available L’articolo propone un percorso d’analisi sulle strategie di riscrittura e di ripresa di alcuni testi di Primo Levi nel film documentario La strada di Levi e nell’opera parallela La prova. Focalizzandosi sul secondo romanzo di Levi, La tregua, questi lavori evadono dalle consuete pratiche di adattamento, sviluppando forme di riscrittura nelle quali la manipolazione critica delle testualità pregresse è posta in tensione con nuovi testi messi in scena, immagini, video, riorientando la percezione dell’ipotesto entro ulteriori linguaggi. È attraverso tale spazio di circolazione di linguaggi artistici e di pratiche intermediali, che gli autori Davide Ferrario e Marco Belpoliti sembrano poter condurre una riflessione sulle forme culturali dello sguardo e delle odierne pratiche di lettura della realtà (nella sua temporalità e memoria come nella sua spazialità e della sua traduzione attraverso codici semiotici molteplici. In tale spostamento costante del proprio oggetto di riscrittura, La strada di Levi e La prova si mostrano così quali nodi o reti di un processo di lettura dialettico del presente e del passato, in un tentativo di tracciare alcune mappe del mondo contemporaneo.   The essay suggests an analysis of the documentary film La strada di Levi and the correlated work La prova. Focusing on Primo Levi’s book La tregua, these works show a different attitude about adaptation through a constant reorientation of the source text and its juxtaposition with new texts and images, and through a projection of these elements within additional languages. In this way, the authors, Davide Ferrario and Marco Belpoliti, offer an experience of an intermedial artistic practice that involves a reflection on the cultural forms through which the texts interpret the reality (and its temporality or memory and its translation through multiple semiotic codes. The effect of this kind of work is the perception of the documentary film as a network that

  20. Multimodal in vivo blood flow sensing combining particle image velocimetry and optical tweezers-based blood steering

    Science.gov (United States)

    Meissner, Robert; Sugden, Wade W.; Siekmann, Arndt F.; Denz, Cornelia

    2018-02-01

    All higher developed organisms contain complex hierarchical networks of arteries, veins and capillaries. These constitute the cardiovascular system responsible for supplying nutrients, gas and waste exchange. Diseases related to the cardiovascular system are among the main causes for death worldwide. In order to understand the processes leading to arteriovenous malformation, we studied hereditary hemorrhagic telangiectasia (HHT), which has a prevalence of 1:5000 worldwide and causes internal bleeding. In zebrafish, HHT is induced by mutation of the endoglin gene involved in HHT and observed to reduce red blood cell (RBC) flow to intersegmental vessels (ISVs) in the tail due to malformations of the dorsal aorta (DA) and posterior cardinal vein (PCV). However, these capillaries are still functional. Changes in the blood flow pattern are observed from in vivo data from zebrafish embryos through particle image velocimetry (PIV). Wall shear rates (WSRs) and blood flow velocities are obtained non-invasively with millisecond resolution. We observe significant increases of blood flow velocity in the DA for endoglin-deficient zebrafish embryos (mutants) at 3 days post fertilization. In the PCV, this increase is even more pronounced. We identified an increased similarity between the DA and the PCV of mutant fish compared to siblings, i.e., unaffected fish. To counteract the reduced RBC flow to ISVs we implement optical tweezers (OT). RBCs are steered into previously unperfused ISVs showing a significant increase of RBC count per minute. We discuss limitations with respect to biocompatibility of optical tweezers in vivo and determination of in vivo wall shear stress (WSS) connected to normal and endoglin-deficicent zebrafish embryos.