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Добірка наукової літератури з теми "In-beam monitoring"

Автор: Grafiati

Опубліковано: 14 березня 2023

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Статті в журналах з теми "In-beam monitoring"

Михалко, Евгения, Evgeniya Mikhalko, Юрий Балабин, Yuriy Balabin, Евгений Маурчев, Evgeniy Maurchev, Алексей Германенко, and Aleksey Germanenko. "New narrow-beam neutron spectrometer in complex monitoring system." Solar-Terrestrial Physics 4, no. 1 (March 31, 2018): 71–74. http://dx.doi.org/10.12737/stp-41201808.

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In the interaction of cosmic rays (CRs) with Earth’s atmosphere, neutrons are formed in a wide range of energies: from thermal (E≈0.025 eV) to ultrarelativistic (E>1 GeV). To detect and study CRs, Polar Geophysical Institute (PGI) uses a complex monitoring system containing detectors of various configurations. The standard neutron monitor (NM) 18-NM-64 is sensitive to neutrons with energies E>50 MeV. The lead-free section of the neutron monitor (BSRM) detects neutrons with energies E≈(0.1÷1) MeV. Also, for sharing with standard detectors, the Apatity NM station has developed and installed a neutron spectrometer with three energy channels and a particle reception angle of 15 degrees. The configuration of the device makes it possible to study the degree of anisotropy of the particle flux from different directions. We have obtained characteristics of the detector (response function and particle reception angle), as well as geometric dimensions through numerical simulation using the GEANT4 toolkit [Agostinelli et al., 2003]. During operation of the device, we collected database of observations and received preliminary results.

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Pennazio, Francesco, Giuseppe Battistoni, Maria Giuseppina Bisogni, Niccolò Camarlinghi, Alfredo Ferrari, Veronica Ferrero, Elisa Fiorina, et al. "Carbon ions beam therapy monitoring with the INSIDE in-beam PET." Physics in Medicine & Biology 63, no. 14 (July 17, 2018): 145018. http://dx.doi.org/10.1088/1361-6560/aacab8.

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Schmidt, Leander, Florian Römer, David Böttger, Frank Leinenbach, Benjamin Straß, Bernd Wolter, Klaus Schricker, Marc Seibold, Jean Pierre Bergmann, and Giovanni Del Galdo. "Acoustic process monitoring in laser beam welding." Procedia CIRP 94 (2020): 763–68. http://dx.doi.org/10.1016/j.procir.2020.09.139.

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Betz, M., O. R. Jones, T. Lefevre, and M. Wendt. "Bunched-beam Schottky monitoring in the LHC." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 874 (December 2017): 113–26. http://dx.doi.org/10.1016/j.nima.2017.08.045.

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Povoli, M., E. Alagoz, A. Bravin, I. Cornelius, E. Bräuer-Krisch, P. Fournier, T. E. Hansen, et al. "Thin silicon strip detectors for beam monitoring in Micro-beam Radiation Therapy." Journal of Instrumentation 10, no. 11 (November 16, 2015): P11007. http://dx.doi.org/10.1088/1748-0221/10/11/p11007.

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Chien, Ring‐Ling, and Michael R. Sogard. "Monitoring the beam flux in molecular beam epitaxy using laser multiphoton ionization." Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films 8, no. 3 (May 1990): 1597–602. http://dx.doi.org/10.1116/1.576772.

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Braccini, Saverio, Roberto Cirio, Marco Donetti, Flavio Marchetto, Giuseppe Pittà, Marco Lavagno, and Vanessa La Rosa. "Segmented ionization chambers for beam monitoring in hadrontherapy." Modern Physics Letters A 30, no. 17 (May 22, 2015): 1540026. http://dx.doi.org/10.1142/s021773231540026x.

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Segmented ionization chambers represent a good solution to monitor the position, the intensity and the shape of ion beams in hadrontherapy. Pixel and strip chambers have been developed for both passive scattering and active scanning dose delivery systems. In particular, strip chambers are optimal for pencil beam scanning, allowing for spatial and time resolutions below 0.1 mm and 1 ms, respectively. The MATRIX pixel and the Strip Accurate Monitor for Beam Applications (SAMBA) detectors are described in this paper together with the results of several beam tests and industrial developments based on these prototypes.

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Klimpki, G., M. Eichin, C. Bula, U. Rechsteiner, S. Psoroulas, D. C. Weber, A. Lomax, and D. Meer. "Real-time beam monitoring in scanned proton therapy." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 891 (May 2018): 62–67. http://dx.doi.org/10.1016/j.nima.2018.02.107.

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Nakagawa, Keiichi, Yukimasa Aoki, Atsuo Akanuma, Yuzou Onogi, Atsurou Terahara, Kouichi Sakata, Nobuharu Muta, Yasuhito Sasaki, Hideyuki Kawakam, and Kazuyuki Hanakawa. "Real-time beam monitoring in dynamic conformation therapy." International Journal of Radiation Oncology*Biology*Physics 30, no. 5 (December 1994): 1233–38. http://dx.doi.org/10.1016/0360-3016(94)90334-4.

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Azizi, Aydin, and Ali Ashkzari. "Health Monitoring in Petrochemical Vessels." Advanced Materials Research 1030-1032 (September 2014): 983–86. http://dx.doi.org/10.4028/www.scientific.net/amr.1030-1032.983.

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Industrial structures deteriorate generally in an uncontrollable rate. To assess the short-term impact due to hazards and the long-term deterioration process due to physical aging and routine operation, structural health monitoring (SHM) is proposed. In this paper as a model of vessel a simply supported beam under constant distributed force is investigated. The objective is to estimate the severity of damage in a known location with sensing devices. As no actuation is consider the problem is solved statically. Finite element method by using MATLAB software to calculate the global stiffness matrix of the smart beam has been applied. It is expected the results show that higher severity of damage causes higher deflection and higher sensor of voltage.

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Більше джерел

Дисертації з теми "In-beam monitoring"

Benot, Morell Alfonso. "Beam position monitoring in the clic drive beam decelerator using stripline technology." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/64067.

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[EN] The Compact Linear Collider (CLIC) is an electron-positron collider conceived for the study of High-Energy Physics in the TeV center of mass energy region, is based on a two-beam operation principle: instead of using active elements (klystrons), the necessary RF power to accelerate the Main Beam (MB) is obtained from the deceleration of a high-current, moderate energy Drive Beam (DB) in the so-called Power Extraction and Transfer Structures (PETS). These structures emit an RF signal of about 130 MW power at 12 GHz. As this frequency is above the cut-o ff frequency of the fundamental mode for the specified beam pipe dimensions (7.6 GHz), the inference propagates from the PETS to the neighboring devices, including the Beam Position Monitors (BPM). According to the CLIC Conceptual Design Report (CDR), an ef ficient beam position monitoring system for the CLIC DB decelerator needs to meet the following requirements: - It should be as simple and economic as possible, as 41580 units are required, amounting to 75% of all CLIC BPMs. - The signal processing scheme should not be a ffected by the PETS interference. This rules out processing the signals at the beam bunching frequency (12 GHz). - The resulting position signal should detect changes in the beam position whose duration is 10 ns or longer. - The required spatial resolution is 2 um for a 23 mm diameter vacuum pipe. - Wide dynamic range: the electronic acquisition system must be able to process signals with extreme levels, induced by either very high (100 A) or very low (3 A) current beams. This PhD thesis describes the electromagnetic and mechanical design of the first prototype BPM developed for the CLIC Drive Beam and its characterization tests in laboratory and with beam. The first two chapters introduce the CLIC project and review the state-of-the-art beam position monitoring techniques. Chapter 3 presents the design of the BPM. The stripline technology has been selected, as it is the only one among the most commonly used BPM techniques to present a suitable frequency response to filter out the RF interference caused by the PETS. Choosing an appropriate length for the electrodes, it is possible to tune one the periodic notches in the stripline frequency response to 12 GHz. The influence of di erent electromagnetic and geometrical aspects is also studied, such as beam coupling impedance or the ratio between longitudinal and transverse dimensions. The design of the electronic acquisition system is presented in Chapter 4, considering the project requirements in terms of resolution (2 u m), accuracy (20 um) and time resolution (10 ns). Due to the high amount of units required, the number of electronics components has been minimized. As the designed signal processing scheme is based on charge integration, it can be adapted to di erent stripline pick-ups by simply modifying the attenuator settings according to the required output signal levels. The laboratory characterization tests of the prototype stripline BPM, in the low and the high frequency ranges, performed with a thin wire and a coaxial waveguide, respectively, are described in Chapter 5. The measurement results are compared with the theoretical estimation and the electromagnetic field simulations. In addition, the high-frequency test reveals that the first prototype stripline BPM does not provide su cient suppression of the 12 GHz PETS RF interference. An additional study proposed several modifications and guidelines for a second prototype stripline BPM. Finally, Chapter 6 presents the beam tests of the prototype stripline BPM at the CLIC Test Facility 3 (CTF3) in the Test Beam Line (TBL), a scaled version of the CLIC Drive Beam decelerator. Two types of tests were performed: linearity/sensivity and resolution. These results are compared to the ones in the laboratory characterization tests. An upper bound of the resolution is estimated performing a Singular Value Decomposition (SVD) analysis.
[ES] El Colisionador Lineal Compacto (Compact Linear Collider, CLIC), un colisionador de electrones y positrones concebido en el CERN para el estudio de la Física de Altas Energías en la región de los TeV, se basa en un principio de funcionamiento de doble haz: en lugar de emplear elementos activos (klystrons) para proporcionar la potencia RF requerida para acelerar el haz principal (Main Beam, MB), ésta se obtiene de la deceleración de un haz secundario (Drive Beam, DB), de alta corriente y energía moderada, en las llamadas estructuras de extracción y transferencia de potencia (Power Extraction and Transfer Structures, PETS). Estas estructuras emiten una señal interferente RF de más de 130 MW de potencia a 12 GHz, que, por estar localizada en una frecuencia superior a la de corte del modo fundamental en el tubo de vacío del haz (7.6 GHz), se propaga por éste hacia los dispositivos adyacentes, entre los cuales se encuentran los sistemas de monitorización de la posición (Beam Position Monitor, BPM). De acuerdo con el informe conceptual de diseño de CLIC (Conceptual Design Report, CDR) , un sistema eficiente de monitorización de la posición del haz en el decelerador del haz secundario deberá cumplir los siguientes requisitos: - Debe ser lo más sencillo y económico posible, ya que se precisan 41580 unidades: el 75% de todos los BPMs de CLIC. - El procesado de señal en el sistema de adquisición deberá ser inmune a la interferencia generada en las PETS. Esto excluye la solución habitual de procesar las señales del BPM a la frecuencia de pulsado del haz (12 GHz). - La señal de posición resultante del procesado debe ser capaz de detectar cambios en la posición del haz de duración igual o mayor a 10 ns (resolución temporal). - La resolución espacial requerida es de 2 um para un tubo de vacío de 23 mm de diámetro, con una calibración precisa. - Amplio rango dinámico: el sistema electrónico de adquisición del BPM debe poder resistir los altos valores de señal provocados por los casos de desviación extrema del haz nominal (se contempla una desviación máxima de la mitad del radio del tubo), así como detectar las señales inducidas por las configuraciones de haz con menor carga de todas las previstas, cuyos niveles serán muy débiles.
[CAT] El Col·lisionador Lineal Compacte (Compact Linear Collider, CLIC), un col·lisionador d'electrons i positrons concebut per l'estudi de la Física d'Altes Energies a la regió dels TeV (energía del centre de massa), es basa en un principi de funcionament de doble feix:en lloc de fer servir elements actius (klystrons) per proporcionar la potència RF requerida per accelerar el feix principal (Main Beam, MB), aquesta s'obtè de la desacceleració d'un feix secundari (Drive Beam, DB), d'alt corrent i energia moderada, a les anomenades estructures d'extracció i transferència de potència (Power Extraction and Transfer Structures, PETS). Aquestes estructures emeten una senyal interferent RF de més de 130 MW de potència a 12 GHz, que, pel fet d'estar localitzada a una freqüència superior a la de tall del mode fonamental al tub de buit del feix (7.6 GHz), es propaga a través d'aquest fins els dispositius adjacents, entre els quals trobem els sistemes de monitorització de la posició (Beam Position Monitor, BPM). D'acord amb l'informe conceptual de disseny de CLIC (Conceptual Design Report, CDR), un sistema eficient de monitorització de la posició del feix al desaccelerador del feix secundari haurà de complir els següents requisits: ¿ - Ha de ser el més senzill i econòmic possible, ja que es necessiten 41580 unitats: el 75% de tots els BPMs de CLIC. ¿ - El processat de la senyal al sistema d'adquisició haurà de ser inmune a la interferència generada als PETS. Això exclou la solució habitual de processar les senyals del BPM a la freqüència de pulsacions del feix (12 GHz). ¿- La senyal de posició resultant del processat ha de ser capaç de detectar canvis a la posició del feix de durada igual o més gran que 10 ns (resolució temporal). ¿- La resolució espaial necessària és de 2 um per a un tub de buit de 23 mm de diàmetre. ¿- Ampli rang dinàmic: el sistema electrònic d'adquisició del BPM ha de poder processar senyals amb nivells extrems, induïdes per feixos de molt alt (100 A) i molt baix (3 A) corrent.
Benot Morell, A. (2016). Beam position monitoring in the clic drive beam decelerator using stripline technology [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/64067
TESIS

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KOSTARA, ELEFTHERIA. "Full-beam PET monitoring in hadron therapy and related coincidence logic." Doctoral thesis, Università di Siena, 2017. http://hdl.handle.net/11365/1013502.

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La terapia adronica è una tecnica che usa protoni e ioni positivi per trattare il cancro. Essa permette di applicare distribuzioni di dose sul tessuto tumorale con precisioni irraggiungibili attraverso altre tecniche, come per esempio quelle radioterapiche convenzionali. Tale precisione fa sì che la tossicità sul tessuto sano circostante venga ridotta al minimo. Al fine di sfruttare a pieno le potenzialità della terapia adronica, è necessario disporre di una tecnica di monitoraggio in-vivo, che permetta di ridurre l'incertezza di range delle particelle e quindi i margini di sicurezza del trattamento. La tomografia ad emissione positronica (PET) è considerata una delle tecniche di imaging non invasivo in-vivo più mature per il monitoraggio del range nei trattamenti radioterapici. Quando l'acquisizione dei dati PET viene eseguita durante l'irraggiamento, il monitoraggio viene indicato come in-beam. Il problema del monitoraggio in-beam è che i dati acquisiti durante l'irraggiamento (in-spill) sono molto rumorosi mentre quelli acquisiti nelle pause (inter-spill) lo sono molto meno. Durante l'inter-spill, tuttavia, il segnale è anche molto debole perché molti degli emettitori β+ non sono stati ancora prodotti. Il rumore di fondo durante l'in-spill è dovuto alla forte radiazione rivelata mentre il fascio colpisce il tessuto bersaglio. Tale radiazione aumenta la probabilità di rivelazione di coincidenze random, a loro volta fonte di rumore nell'imaging PET. La radiazione di fondo può essere causata dal decadimento di emettitori β+ con vita media nell'ordine dei millisecondi, da raggi γ prodotti immediati (prompt) di reazioni nucleari non correlate al decadimento β+, da produzioni di coppie positrone-elettrone o da neutroni. Gli eventi random non possono essere discriminati dai decadimenti β+ utili, e non possono essere corretti con le tecniche convenzionali di stima delle coincidenze random a causa della mancanza di correlazione temporale tra i decadimenti β+ e i prodotti nucleari immediati. Allo stato dell'arte sono stati proposti due metodi per separare le coincidenze in-spill che si verificano durante la fase di estrazione dall'acceleratore da quelle che si verificano durante la fase di accelerazione. Le prime sono naturalmente più rumorose delle seconde, in quanto durante la fase di accelerazione sono assenti gli eventi prompt. Entrambi i metodi utilizzano informazioni sulla microstruttura del fascio da fonti esterne. Nel primo metodo, il segnale RF dall'acceleratore viene utilizzato per generare un segnale di gate all'interno del sistema di acquisizione PET. Nel secondo, il segnale di gate viene prodotto da un rivelatore di particelle inserito nel percorso del fascio prima del bersaglio. In questa tesi, le fasi della microstruttura del fascio vengono rivelate direttamente analizzando la distribuzione temporale degli eventi PET acquisiti in-spill. A tal fine, un nuovo algoritmo è stato sviluppato e validato in simulazione e sperimentalmente per il rilevamento della microstruttura temporale del fascio. I risultati di simulazione mostrano che e possibile implementare l'algoritmo su un FPGA e sfruttare le informazioni da esso prodotte per discriminare le coincidenze avvenute durante le fasi di estrazione da quelle avvenute durante le fasi di accelerazione. La distribuzione spaziale 3D ei profili di attività 1D degli eventi di coincidenza sono ricavati con un algoritmo di ricostruzione tomografica ML-EM per i dati interspill e in-spill. Il rumore di background è visibile nelle immagini ricostruite da dati sperimentali in-spill. Dopo aver filtrato i dati in-spill, scartando gli eventi di coincidenza che si verificano durante la fase di estrazione, si dimostra che l'immagine ricostruita migliora significativamente. Nel profilo di attività 1D si osserva una forte diminuzione della baseline del segnale, corrispondente al contributo delle coincidenze random. In particolare, il rapporto fra il picco di attività nel target diviso per il livello di fondo migliora di un fattore 4.8. Questa attività è stata sviluppata all'interno dei progetti INSIDE e INFIERI (FP7-PEOPLE-2012-ITN project number 317446), finanziati rispettivamente da MIUR e EU.
Hadron therapy is a widely employed technique that uses protons and heavy ions to treat cancer. It has the potential of delivering highly conformal dose distributions to the tumor volume while sparing the surrounding healthy tissue, thanks to the dose distribution characterized by the Bragg peak at the end of charged particles range. In order to exploit the full potential of hadron therapy, an in vivo monitoring technique is desirable in order to reduce the uncertainties and therefore the treatment safety margins. Positron emission tomography (PET) is considered one of the most promising in vivo non-invasive imaging techniques for monitoring the particle range in radiation treatments. One of the data acquisition methods is the so-called in-beam which is performed during irradiation at the treatment site. The problem of in-beam monitoring is that in-spill data are much noisier while inter-spill data for accelerators with high duty cycles, are much less due to the small number of acquired decays. During the spills, the noisy background is due to the presence of strong beam-induced radiation that increases the random coincidence rates. This background might originate from the decay of β+ emitters with half-lives in millisecond range and high endpoint energies, by γ-rays following nuclear reactions not related to β+ decay or by pair productions and neutrons. The noisy events cannot be separated from the usable decays of long-lived β+ emitters and cannot be corrected with standard random coincidence correction techniques because of the time-correlation of the beam-induced background with the ion beam microstructure. Until now, only two methods exist for identifying coincident events that occur during the microbunches in the spills. Both of them use information about the beam microstructure from external sources. In the first method, the RF signal from the accelerator is used externally and the data processing is done offline. In the second one, a fast particle detector placed in the beam path before the target is used and the process is triggered only when a particle arrives. With this thesis, the correlation between the beam microstructure and the RF of the synchrotron is confirmed by analyzing the events in the spills without the need of an external signal. An algorithm for the calculation of the period of the beam microstructure is developed. Small differences in the period between the spills impose the separate analysis for every spill. The period is calculated with 4 digits precision in nanosecond time scale, making a significant difference to the representation of the microbunch. In the end, the firmware related to the algorithm for the calculation of the period of the beam microstructure is developed using only the events in the spills. The simulation results show that it is possible the algorithm to be implemented in an FPGA and provide information about the period of the beam microstructure in real time. Moreover, a coincidence sorter is developed in order to provide real time coincidence detection. The simulation results for the two different architectures of the sorter that uses comparators with two and three inputs, are presented. The 3D spatial distribution and the 1D activity profiles of the coincidence events are constructed for inter-spill and in-spill data. The strong radiation background is visible in the reconstructed images, especially before the entrance surface of the phantom and at the end of the activity range with a tail. After filtering out the in-spill data by discarding the coincidence events that occur in a sub-interval of the microbunch, it is shown that the reconstructed image improves severely. In the 1D activity profile, one can observe that the number of coincidence events before the entrance surface of the phantom decreases significantly. This might happen because neutrons are discarded since they are detected a few ns later after the interaction of the beam with the nuclei. Results show that the signal to noise ratio (SNR), defined as the activity peak in the phantom divided by the background level, is improved by a factor of about 4.8 with respect to the in-spill signal. In the end, it is important to mention that this activity has been developed within the projects INSIDE and INFIERI (FP7-PEOPLE-2012-ITN project number 317446) funded by MIUR and EU respectively.

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Shakirin, Georgy. "System solution for in beam positron emission tomography monitoring of radiation therapy." Doctoral thesis, Dresden TUDpress, 2009. http://d-nb.info/996092544/04.

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Rowbottom, Carl Graham. "Optimisation of beam-orientations in conformal radiotherapy treatment planning." Thesis, Institute of Cancer Research (University Of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314088.

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Ahmed, Syed Naeem. "Quantum fluctuations in a segmented ionization chamber for beam monitoring of synchrotron radiation." [S.l. : s.n.], 1998. http://deposit.ddb.de/cgi-bin/dokserv?idn=957510330.

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Crespo, Paulo. "Optimization of In-Beam Positron Emission Tomography for Monitoring Heavy Ion Tumor Therapy." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-28512.

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In-beam positron emission tomography (in-beam PET) is currently the only method for an in-situ monitoring of highly tumor-conformed charged hadron therapy. In such therapy, the clinical effect of deviations from treatment planning is highly minimized by implementing safety margins around the tumor and selecting proper beam portals. Nevertheless, in-beam PET is able to detect eventual, undesirable range deviations and anatomical modifications during fractionated irradiation, to verify the accuracy of the beam portal delivered and to provide the radiotherapist with an estimation of the difference in dosage if the treatment delivered differs from the planned one. In a first study within this work, a set of simulation and fully-3D reconstruction routines shows that minimizing the opening angle of a cylindrical camera is determinant for an optimum quality of the in-beam PET images. The study yields two favorite detector geometries: a closed ring or a dual-head tomograph with narrow gaps. The implementation of either detector geometry onto an isocentric, ion beam delivery (gantry) is feasible by mounting the PET scanner at the beam nozzle. The implementation of an in-beam PET scanner with the mentioned detector geometries at therapeutic sites with a fixed, horizontal beam line is also feasible. Nevertheless, knowing that previous in-beam PET research in Berkeley was abandoned due to detector activation (Bismuth Germanate, BGO), arising most probably from passive beam shaping contaminations, the proposed detector configurations had to be tested in-beam. For that, BGO was substituted with a state-of-the-art scintillator (lutetium oxyorthosilicate, LSO) and two position sensitive detectors were built. Each detector contains 32 pixels, consisting of LSO finger-like crystals coupled to avalanche photodiode arrays (APDA). In order to readout the two detectors operated in coincidence, either in standalone mode or at the GSI medical beam line, a multi-channel, zero-suppressing free, list mode data acquisition system was built.The APDA were chosen for scintillation detection instead of photomultiplier tubes (PMT) due to their higher compactness and magnetic field resistance. A magnetic field resistant detector is necessary if the in-beam PET scanner is operated close to the last beam bending magnet, due to its fringe magnetic field. This is the case at the isocentric, ion beam delivery planned for the dedicated, heavy ion hospital facility under construction in Heidelberg, Germany. In-beam imaging with the LSO/APDA detectors positioned at small target angles, both upbeam and downbeam from the target, was successful. This proves that the detectors provide a solution for the proposed next-generation, improved in-beam PET scanners. Further confirming this result are germanium-detector-based, spectroscopic gamma-ray measurements: no scintillator activation is observed in patient irradiation conditions. Although a closed ring or a dual-head tomograph with narrow gaps is expected to provide improved in-beam PET images, low count rates in in-beam PET represent a second problem to image quality. More importantly, new accelerator developments will further enhance this problem to the point of making impossible in-beam PET data taking if the present acquisition system is used. For these reasons, two random-suppression methods allowing to collect in-beam PET events even during particle extraction were tested. Image counts raised almost twofold. This proves that the methods and associated data acquisition technique provide a solution for next-generation, in-beam positron emission tomographs installed at synchrotron or cyclotron radiotherapy facilities.

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Crespo, Paulo. "Optimization of In-Beam Positron Emission Tomography for Monitoring Heavy Ion Tumor Therapy." Forschungszentrum Rossendorf, 2006. https://hzdr.qucosa.de/id/qucosa%3A21679.

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Buga, Vlad, and Roysten Jason Dsouza. "In-process monitoring for Electron Beam Additive Manufacturing using an infrared camera system." Thesis, KTH, Industriell produktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-245064.

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Additive Manufacturing (AM) is being embraced at a rapid rate, mainly due to its advantages over conventional machining. These include the possibility to create parts with complex geometries, while minimizing waste. The exponential growth of the technology has brought about challenges in quality assurance, which has proved a key barrier to large scale adoption. Developing in-process monitoring techniques for AM is an ongoing challenge, and is still a long way off from the more established techniques developed for conventional machining. Previous research has brought about instances, where the technology has been implemented, with the focus on titanium alloys. This study aims to contribute to the research being carried out within in-process monitoring, and focusses on the Electron Beam Melting (EBM) process. The material being monitored is Inconel 625, to increase the scope of research to higher temperature ranges. The most suitable monitoring technology and vendor for the equipment, is narrowed down through a review of previous literature and market research. Experimental trials to analyze the performance of the monitoring technique with Inconel 625 are carried out. The extracted data is then analyzed using image processing, which gives interesting results with regards to temperature fluctuations over successive layers of the build. The events within the build process for a layer, show interesting deviations in temperature, which are mapped and presented as graphs. The after-rake event, shows a particularly large deviation, which is then attributed to differential heating of the metal powder during the rake phase. This observation is supported by noticing ‘cold-spots’ in extracted images of the build. The results are discussed, and future scope for the study is conveyed. The intention of this study is to provide a base for further research into in-process monitoring for higher temperature ranges and contribute to the development of real-time process monitoring for AM.
“Additive manufacturing” (AM) eller “friformsframställning” har snabbt ökat i omfattning, främst tack vare dess fördelar jämfört med konventionell bearbetning. Fördelarna inkluderar möjligheten att tillverka delar med komplexa geometrier medan slöseri minimeras. Den exponentiella tillväxten av tekniken har medfört utmaningar inom kvalitetssäkring, vilket har visat sig vara ett hinder för storskalig anpassning. Utveckling av processövervakningstekniker för AM är en pågående utmaning, och ligger efter i utveckling jämfört med de mer etablerade teknikerna som utvecklats för konventionell bearbetning. Tidigare forskning har visat fall där tekniken har implementerats med fokus på titanlegeringar. Denna studie syftar till att bidra till den forskning som genomförs inom processövervakning och fokuserar på EBM-processen (Electronic Beam Melting). Materialet som övervakas är Inconel 625, för att expandera forskningsområdet till högre temperaturområden. Den mest lämpliga övervakningstekniken och leverantör av utrustning väljs ut genom en gransking av tidigare litteratur och en marknadsundersökning. Experimentella försök för att analysera övervakningsteknikens prestanda med Inconel 625 utförs. De extraherade data analyseras sedan med bildbehandling, vilket ger intressanta resultat med avseende på temperaturfluktuationer över successiva lager av byggobjektet. Händelserna inom byggprocessen för ett lager visar intressanta avvikelser i temperatur, vilka kartläggs och presenteras som grafer. Tillståndet efter räfsning visar en särskilt stor avvikelse, som sedan tillskrivs differentialvärme av metallpulvret under räfsningsfasen. Denna observation stöds genom att notera "cold-spots" i extraherade bilder av byggobjektet. Resultaten diskuteras och vidare omfång för studien framförs. Avsikten med denna studie är att ta fram en grund för vidare forskning i processövervakning för högre temperaturområden och bidra till utvecklingen av realtidsprocessövervakning för AM.

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Kelly, Brendan T. "A Newly Proposed Method for Detection, Location, and Identification of Damage in Prestressed Adjacent Box Beam Bridges." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1339520527.

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Alessio, Federico. "Beam, Background and Luminosity Monitoring in LHCb and Upgrade of the LHCb Fast Readout Control." Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX22044/document.

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Le travail présenté dans cette thèse a été effectué au sein de la collaboration internationale LHCb qui a conçue et qui exploite un détecteur pour la physique des particules auprès de l’accélérateur proton-proton, le LHC, au CERN à Genève. Ces travaux concerne l’opération de l’expérience dans son ensemble. Ils ont montré toutes leurs forces pendant la première année de prise de données qui a débutée fin 2009. Ils couvrent plusieurs systèmes qui sont très dépendant les uns des autres. Deux systèmes sont plus particulièrement étudiés. Le premier est en charge de la surveillance des faisceaux, du niveau des bruits de fond et de la luminosité. Le second permet la visualisation, l’analyse et l’optimisation des conditions expérimentales. Ces deux systèmes sont fortement interconnectés. En effet, l’amélioration de la qualité des faisceaux de la machine et la diminution du bruit de fond augmentent le nombre de collisions utiles pour la physique. En même temps, comprendre les paramètres clefs qui gouvernent l’opération de l’expérience permet de les optimiser et d’améliorer la qualité des données collectées
There are two main central topics in the thesis: the LHCb beam, background and luminosity monitoring systems and the LHCb optimization systems of experimental conditions. These systems are heavily connected to each other, as improving the machine beam, background and luminosity conditions will automatically improve global operation by maximizing the ratio of luminosity recorded over signal background. At the same time, improving the operation of the experiment will help improve luminosity, by studying more accurately the beam and background conditions and therefore improving the LHC machine settings. In this thesis, the systems to accomplish the requirements of these two main topics are described in detail

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Книги з теми "In-beam monitoring"

Lone, M. A. Self-powered detector probes for electron and gamma-ray beam monitoring in high-power industrial accelerators. Chalk River, Ont: Chalk River Laboratories, 1992.

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Hughes, Jim. Radiation protection. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198813170.003.0005.

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The basics of radiation protection in theatre for the patient follow principles similar to those used in plain-film imaging. These include ensuring positive identification of the patient, justification of radiation exposure, avoiding irradiation of pregnant patients wherever possible, minimization and optimization of exposures performed (ALARP principle), protection of all staff involved, and recording and monitoring of all exposures performed. This chapter covers the aspects of protection from radiation for the patient, surgical team, and the radiographer when performing imaging during surgical interventions. Topics covered include the use of beam collimation, minimizing exposure to the patient and team, radiation scatter, and the use and requirements of radiation shielding such as lead aprons and barriers.

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Peet, Deborah J., Patrick Horton, Colin J. Martin, and David G. Sutton. Radiotherapy: external beam radiotherapy. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199655212.003.0019.

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Design principles for radiotherapy facilities using X-ray, γ‎-ray, and electron beams are described, especially the requirements for primary and secondary shielding and maze and door entrances. These features are illustrated with reference to the shielded rooms (bunkers) required for linear accelerators, and example calculations are included for shielding and maze design to achieve required dose constraints. The impact of new clinical practices with intensity modulated radiation fields and flattening filter-free operation is also considered. Engineering controls and features for safe operation are described, and good practice in bunker construction and the provision of services to avoid weaknesses in the shielding is outlined. The principle shielding requirements for TomoTherapyTM, CyberKnifeTM, Gamma KnifeTM units, and kilovoltage X-ray units are also described. Finally, personnel monitoring, commissioning surveys, and environmental monitoring in radiation protection management in radiotherapy are discussed. Data for calculating shielding thickness and X-ray scatter for maze design are provided.

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Частини книг з теми "In-beam monitoring"

Maischner, D. "Monitoring the Degree of Full Penetration in Laser Beam Welding." In Laser in der Technik / Laser in Engineering, 515–18. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-84736-3_86.

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Saxner, M., and A. Ahnesjö. "Implementation of a Pencil Beam Model in the TMS-Radix Treatment Planning System." In Tumor Response Monitoring and Treatment Planning, 487–93. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-48681-4_80.

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Shevtsov, Sergey, Igor Zhilyaev, Paul Oganesyan, and Vladimir Akopyan. "A Probabilistic Approach to the Crack Identification in a Beam-like Structure Using Monitored Mode Shapes and Their Curvature Data with Uncertainty." In Applied Condition Monitoring, 447–61. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-20463-5_34.

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Auberger, T., W. Reuschel, M. Mayr, P. Kneschaurek, P. Lukas, B. Clasen, and A. Breit. "Mixed-Beam Photon-Neutron Therapy in Recurrences and Nodal Metastases of Head and Neck Cancer." In Tumor Response Monitoring and Treatment Planning, 803–10. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-48681-4_133.

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Xiao, Yancai, Kun Fu, Zhuang Li, Zhiping Zeng, Jian Bai, Zhibin Huang, Xudong Huang, and Yu Yuan. "Research on Construction Process of Steel Beam Incremental Launching Based on Finite Element Method." In Lecture Notes in Civil Engineering, 254–62. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-1260-3_22.

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AbstractIn order to ensure the normal operation of the traffic under the bridge, reasonable calculation methods and construction techniques should be adopted for the construction of the newly added railway station. This paper establishes a structural calculation finite element model to calculate and analyze the various construction stages of the steel beam incremental launching construction of the newly-added Gaoping station on the Yichuang-Wanzhou Railway, and systematically study the mechanical properties of the steel beam in the process. The results show that: (1) The deflection of each rod can meet the requirements of the railway bridge steel structure construction specification. However, when the length of the front cantilever of the steel beam reaches 11.4 m, the maximum deflection of the upper and lower chord bars is close to the limit. (2) The load-bearing capacity of each member of the steel beam meets the requirements, which indicates that the structural design of the steel beam and the incremental launching construction plan are reasonable. (3) In view of the complexity and uncertainty of the incremental launching construction process, real-time monitoring of the construction process is required, and the beam should be dropped in time when abnormal conditions occur to ensure the safe operation of the existing line.

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Sauerwein, W., F. Pöller, J. Rassow, and H. Sack. "Enhancement of the Absorbed Dose in a d(14) + Be Fast-Neutron Beam by 10B Neutron-Capture Therapy." In Tumor Response Monitoring and Treatment Planning, 797–801. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-48681-4_132.

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Shao, Zhengjie, Siyi Liu, Wei Wu, Xi Chen, and Guanhua Wu. "The AE Monitoring in Load Testing in Helicopter Tail Beam with Prefabricated Defects." In Springer Proceedings in Physics, 543–46. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-15-9837-1_48.

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Tu, J. Q., C. B. Yun, X. Xu, Z. F. Tang, and J. J. Wu. "PCA-Based Temperature Effect Compensation in Monitoring of Steel Beam Using Guided Waves." In Lecture Notes in Civil Engineering, 85–96. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-8079-6_8.

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Zembaty, Zbigniew, Seweryn Kokot, and Piotr Bobra. "Application of Rotation Rate Sensors in Measuring Beam Flexure and Structural Health Monitoring." In Seismic Behaviour and Design of Irregular and Complex Civil Structures II, 65–76. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-14246-3_6.

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Li, Lili, Hao Luo, He Qi, and Feiyu Wang. "Sensor Fault Diagnosis Method of Bridge Monitoring System Based on FS-LSTM." In Advances in Frontier Research on Engineering Structures, 487–501. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-8657-4_44.

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AbstractAn improved long-short-term memory neural network (FS-LSTM) fault diagnosis method is proposed based on the problems of damage false alarm, data of health monitoring system incorrect caused by sensor fault in bridge structure health monitoring system. The method is verified by simulating three-span continuous beams to install several sensors and considering the five failures of one sensor, the faults such as: constant, gain, bias, gain linearity bias, and noise. At first, several pieces of white noise data are randomly generated, and each piece of white noise data is applied as a ground pulsation excitation to the structure support, and the acceleration response of the structure at the sensor location is calculated. Simultaneously, each structural response record of each sensor adds white noise with the same signal-to-noise ratio to obtain the test value of each sensor; Secondly, in order to study the generality, except for the five types of faulty sensors in sequence, one sensor is randomly selected from each of the remaining spans, to verify whether there will be a situation where an intact sensor is misdiagnosed as a faulty sensor; Finally, the FS-LSTM network is constructed through the training set to predict the acceleration data, determine the sensor fault threshold, and compare the residual sequence with the fault threshold to diagnose whether the sensor is faulty. The case research of a three-span continuous beam shows that when the above-mentioned five types of faults occur in the sensor, the proposed method can correctly determine whether the sensor is faulty, and it will not be misdiagnosed, which can be used for daily bridge health monitoring. Furthermore, it provides a new method for the maintenance of the bridge health monitoring system.

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Тези доповідей конференцій з теми "In-beam monitoring"

Steen, W. M., and V. M. Weerasinghe. "In Process Beam Monitoring." In 1986 Quebec Symposium, edited by Walter W. Duley and Robert W. Weeks. SPIE, 1986. http://dx.doi.org/10.1117/12.938882.

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Sunaoshi, Hitoshi, Munehiro Ogasawara, Jun Takamatsu, and Naoharu Shimomura. "In-situ beam position monitoring system for electron-beam lithography." In SPIE's International Symposium on Optical Science, Engineering, and Instrumentation, edited by Eric Munro. SPIE, 1999. http://dx.doi.org/10.1117/12.370133.

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Nootz, Gero A., Silvia C. Matt, Andrey V. Kanaev, Ewa Jarosz, and Weilin W. Hou. "Beam wander due to optical turbulence in water (Conference Presentation)." In Ocean Sensing and Monitoring IX, edited by Weilin (Will) Hou and Robert A. Arnone. SPIE, 2017. http://dx.doi.org/10.1117/12.2264922.

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Müller-Borhanian, J., C. Deininger, and F. Dausinger. "In-process monitoring during laser beam welding." In PICALO 2006: 2nd Pacific International Conference on Laser Materials Processing, Micro, Nano and Ultrafast Fabrication. Laser Institute of America, 2006. http://dx.doi.org/10.2351/1.5056939.

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Garcia-Weidner, A., A. V. Khomenko, and Diana Tentori-Santa-Cruz. "Probe-beam scanning method for beam-coupling monitoring in photorefractive crystals." In Second Iberoamerican Meeting on Optics, edited by Daniel Malacara-Hernandez, Sofia E. Acosta-Ortiz, Ramon Rodriguez-Vera, Zacarias Malacara, and Arquimedes A. Morales. SPIE, 1996. http://dx.doi.org/10.1117/12.231044.

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DE OLIVEIRA, MARIO, and DANIEL INMAN. "PCA-based Method for Damage Detection Exploring Electromechanical Impedance in a Composite Beam." In Structural Health Monitoring 2015. Destech Publications, 2015. http://dx.doi.org/10.12783/shm2015/94.

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Dearden, G., M. Sharp, P. W. French, K. G. Watkins, and L. I. Green. "Initial studies of laser beam performance monitoring using a novel camera-based in-line beam monitoring system." In ICALEO® 2001: Proceedings of the Laser Materials Processing Conference and Laser Microfabrication Conference. Laser Institute of America, 2001. http://dx.doi.org/10.2351/1.5059773.

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CORRADO, NICOLO, CECILIA SURACE, LORENZO MONTANARI, and ANDREA SPAGNOLI. "Comparing Three Derivative Discontinuities Detection Methods for the Localisation of Cracks in Beam-like Structures." In Structural Health Monitoring 2015. Destech Publications, 2015. http://dx.doi.org/10.12783/shm2015/173.

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Zheng, Peng, David W. Greve, and Irving J. Oppenheim. "Ultrasonic flaw detection in a monorail box beam." In SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring. SPIE, 2009. http://dx.doi.org/10.1117/12.815515.

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Sha, Ganggang, Maciej Radzienski, Rohan Soman, Maosen Cao, and Wieslaw Ostachowicz. "Concentrated mass localization in beam-like structures using natural frequencies." In Health Monitoring of Structural and Biological Systems IX, edited by Paul Fromme and Zhongqing Su. SPIE, 2020. http://dx.doi.org/10.1117/12.2557950.

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Звіти організацій з теми "In-beam monitoring"

Cooke, M. S. Precision Beam Parameter Monitoring in a Measurement of the Weak Mixing Angle in Moeller Scattering. Office of Scientific and Technical Information (OSTI), April 2005. http://dx.doi.org/10.2172/839851.

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Sokol, J., T. J. Pultz, and V. Bulzgis. Monitoring wetland hydrology in Atlantic Canada using multi-temporal and multi-beam RADARSAT data. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2000. http://dx.doi.org/10.4095/219630.

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Lee, J. W., S. J. Pearton, C. R. Abernathy, G. A. Vawter, R. J. Shul, M. M. Bridges, and C. L. Willison. In-situ monitoring of etch by-products during reactive ion beam etching of GaAs in chlorine/argon. Office of Scientific and Technical Information (OSTI), December 1997. http://dx.doi.org/10.2172/292864.

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Whalen, Michael. Trigger for Momentum Calibration and Beam Position Monitoring by Means of Decay-in-Orbit $\mu$ in the Mu2e Experiment [Poster]. Office of Scientific and Technical Information (OSTI), June 2019. http://dx.doi.org/10.2172/1579218.

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Volwater, Joey, and Ralf van Hal. Monitoring zeebodemafval in de Noordzee en Waddenzee naar aanleiding van de containerramp met de MSC Zoe : Beam trawl survey en Demersal Fish survey 2019. IJmuiden: Wageningen Marine Research, 2019. http://dx.doi.org/10.18174/506606.

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Rahmani, Mehran, Xintong Ji, and Sovann Reach Kiet. Damage Detection and Damage Localization in Bridges with Low-Density Instrumentations Using the Wave-Method: Application to a Shake-Table Tested Bridge. Mineta Transportation Institute, September 2022. http://dx.doi.org/10.31979/mti.2022.2033.

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This study presents a major development to the wave method, a methodology used for structural identification and monitoring. The research team tested the method for use in structural damage detection and damage localization in bridges, the latter being a challenging task. The main goal was to assess capability of the improved method by applying it to a shake-table-tested prototype bridge with sparse instrumentation. The bridge was a 4-span reinforced concrete structure comprising two columns at each bent (6 columns total) and a flat slab. It was tested to failure using seven biaxial excitations at its base. Availability of a robust and verified method, which can work with sparse recording stations, can be valuable for detecting damage in bridges soon after an earthquake. The proposed method in this study includes estimating the shear (cS) and the longitudinal (cL) wave velocities by fitting an equivalent uniform Timoshenko beam model in impulse response functions of the recorded acceleration response. The identification algorithm is enhanced by adding the model’s damping ratio to the unknown parameters, as well as performing the identification for a range of initial values to avoid early convergence to a local minimum. Finally, the research team detect damage in the bridge columns by monitoring trends in the identified shear wave velocities from one damaging event to another. A comprehensive comparison between the reductions in shear wave velocities and the actual observed damages in the bridge columns is presented. The results revealed that the reduction of cS is generally consistent with the observed distribution and severity of damage during each biaxial motion. At bents 1 and 3, cS is consistently reduced with the progression of damage. The trends correctly detected the onset of damage at bent 1 during biaxial 3, and damage in bent 3 during biaxial 4. The most significant reduction was caused by the last two biaxial motions in bents 1 and 3, also consistent with the surveyed damage. In bent 2 (middle bent), the reduction trend in cS was relatively minor, correctly showing minor damage at this bent. Based on these findings, the team concluded that the enhanced wave method presented in this study was capable of detecting damage in the bridge and identifying the location of the most severe damage. The proposed methodology is a fast and inexpensive tool for real-time or near real-time damage detection and localization in similar bridges, especially those with sparsely deployed accelerometers.

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Dudley, J. P., and S. V. Samsonov. SAR interferometry with the RADARSAT Constellation Mission. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329396.

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The RADARSAT Constellation Mission (RCM) is Canada's latest system of C-band Synthetic Aperture Radar (SAR) Earth observation satellites. The system of three satellites, spaced equally in a common orbit, allows for a rapid four-day repeat interval. The RCM has been designed with a selection of stripmap, spotlight, and ScanSAR beam modes which offer varied combinations of spatial resolution and coverage. Using Differential Interferometric Synthetic Aperture Radar (DInSAR) techniques, the growing archive of SAR data gathered by RCM can be used for change detection and ground deformation monitoring for diverse applications in Canada and around the world. In partnership with the Canadian Space Agency (CSA), the Canada Centre for Mapping and Earth Observation (CCMEO) has developed an automated system for generating standard and advanced deformation products and change detection from SAR data acquired by RCM and RADARSAT-2 satellites using DInSAR processing methodology. Using this system, this paper investigates four key interferometric properties of the RCM system which were not available on the RADARSAT-1 or RADARSAT-2 missions: The impact of the high temporal resolution of the four-day repeat cycle of the RCM on temporal decorrelation trends is tested and fitted against simple temporal decay models. The effect of the normalization and the precision of the radiometric calibration on interferometric spatial coherence is investigated. The performance of the RCM ScanSAR mode for wide area interferometric analysis is tested. The performance of the novel RCM Compact-polarization (CP) mode for interferometric analysis is also investigated.

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Dahm, Philipp, Michelle Brasure, Elizabeth Ester, Eric J. Linskens, Roderick MacDonald, Victoria A. Nelson, Charles Ryan, et al. Therapies for Clinically Localized Prostate Cancer. Agency for Healthcare Research and Quality (AHRQ), September 2020. http://dx.doi.org/10.23970/ahrqepccer230.

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Objective. To update findings from previous Agency for Healthcare Research and Quality (AHRQ)- and American Urological Association (AUA) funded reviews evaluating therapies for clinically localized prostate cancer (CLPC). Sources. Bibliographic databases (2013–January 2020); ClinicalTrials.gov; systematic reviews Methods. Controlled studies of CLPC treatments with duration ≥5 years for mortality and metastases and ≥1 year for quality of life and harms. One investigator rated risk of bias (RoB), extracted data, and assessed certainty of evidence; a second checked accuracy. We analyzed English-language studies with low or medium RoB. We incorporated findings from randomized controlled trials (RCTs) identified in the prior reviews if new RCTs provided information on the same intervention comparison. Results. We identified 67 eligible references; 17 were unique RCTs. Among clinically rather than prostate specific antigen (PSA) detected CLPC, Watchful Waiting (WW) may increase mortality and metastases versus Radical Prostatectomy (RP) at 20+ years. Urinary and erectile dysfunction were lower with WW versus RP. WW’s effect on mortality may vary by tumor risk and age but not by race, health status, comorbidities, or PSA. Active Monitoring (AM) probably results in little to no difference in mortality in PSA detected CLPC versus RP or external beam radiation (EBR) plus Androgen Deprivation (AD) regardless of tumor risk. Metastases were slightly higher with AM. Harms were greater with RP than AM and mixed between EBR plus AD versus AM. 3D-conformal EBR and AD plus low-dose-rate brachytherapy (BT) provided a small reduction in all-cause mortality versus three dimensional conformal EBR and AD but little to no difference on metastases. EBR plus AD versus EBR alone may result in a small reduction in mortality and metastases in higher risk disease but may increase sexual harms. EBR plus neoadjuvant AD versus EBR plus concurrent AD may result in little to no difference in mortality and genitourinary toxicity. Conventionally fractionated EBR versus ultrahypofractionated EBR may result in little to no difference in mortality and metastases and urinary and bowel toxicity. Active Surveillance may result in fewer harms than photodynamic therapy and laparoscopic RP may result in more harms than robotic-assisted RP. Little information exists on other treatments. No studies assessed provider or hospital factors of RP comparative effectiveness. Conclusions. RP reduces mortality versus WW in clinically detected CLPC but causes more harms. Effectiveness may be limited to younger men or to those with intermediate risk disease and requires many years to occur. AM results in little to no mortality difference versus RP or EBR plus AD. EBR plus AD reduces mortality versus EBR alone in higher risk CLPC but may worsen sexual function. Adding low-dose-rate BT to 3D-conformal EBR and AD may reduce mortality in higher risk CLPC. RCTs in PSA-detected and MRI staged CLPC are needed.

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APPLICATION OF HYDRAULIC SYNCHRONOUS LIFTING TECHNOLOGY IN THE CONSTRUCTION OF LONG-SPAN HYBRID STEEL STRUCTURES. The Hong Kong Institute of Steel Construction, August 2022. http://dx.doi.org/10.18057/icass2020.p.070.

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Анотація:

The aim of this study was to solve technical problems, such as uneven structures, multiple lifting points, high accuracy control requirements, and multi-disciplinary collaborative work, in the process of lifting and hoisting long-span hybrid steel structures based on the lifting work of a steel roof and steel beams of the Hunan Radio and Television studio F. First, after conducting research on the comparison and selection of the construction scheme, lifting process, quality control and other aspects, a floor assembly + hydraulic lifting + overhead supplementary bar construction plan was proposed. The large-section steel beam and truss hybrid structure system with different bottom chord elevations was divided into two units for synchronous lifting, with weights of 715 tons and 340 tons, lifting heights of 21.5 metres and 15 metres, and a maximum span of 50.4 metres , Second, the maximum vertical displacement, maximum stress ratio of the members, lifting reaction force frame and overall stability of the hybrid structure during the lifting process were analysed, and the results showed that they all met the requirements. Finally, the monitoring data of the field construction process were in good agreement with the numerical calculation results, further verifying the rationality and feasibility of hydraulic synchronous lifting technology, which can provide guidance and a reference for the construction of similar long-span hybrid steel structures.

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